Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf
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42029 Publications
Detection Efficacy of 18F-PSMA-1007 PET/CT in 251 Patients with Biochemical Recurrence of Prostate Cancer After Radical Prostatectomy
Giesel, F. L.; Knorr, K.; Spohn, F.; Will, L.; Maurer, T.; Flechsig, P.; Neels, O.; Schiller, K.; Amaral, H.; Weber, W.; Haberkorn, U.; Schwaiger, M.; Kratochwil, C.; Choyke, P.; Kramer, V.; Kopka, K.; Eiber, M.
Abstract
Prostate-specific membrane antigen (PSMA)–targeted PET imaging recently emerged as a new method for the staging and restaging of prostate cancer. Most published studies investigated the diagnostic potential of 68Ga-labeled PSMA agents that are excreted renally 18F-PSMA-1007 is a novel PSMA ligand that has excellent preclinical characteristics and that is only minimally excreted by the urinary tract, a potential advantage for pelvic imaging. The aim of this study was to investigate the diagnostic efficacy of 18F-PSMA-1007 for biochemical recurrence (BCR) after radical prostatectomy. Methods: From 3 academic centers, 251 patients with BCR after radical prostatectomy were evaluated in a retrospective analysis. Patients who had received second-line androgen deprivation therapy (ADT) or chemotherapy were excluded, but prior first-line ADT exposure was allowed. The median prostate-specific antigen (PSA) level was 1.2 ng/mL (range, 0.2–228 ng/mL). All patients underwent PSMA PET/CT at 92 ± 26 min after injection of 301 ± 46 MBq of 18FPSMA-1007. The rate of detection of presumed recurrence sites was correlated with the PSA level and original primary Gleason score. A comparison to a subset of patients treated previously with ADT was undertaken. Results: Of the 251 patients, 204 (81.3%) had evidence of recurrence on 18F-PSMA-1007 PET/CT. The detection rates were 94.0% (79/84), 90.9% (50/55), 74.5% (35/47), and 61.5% (40/65) for PSA levels of greater than or equal to 2, 1 to less than 2, 0.5 to less than 1, and 0.2 to less than 0.5 ng/mL, respectively. 18FPSMA-1007 PET/CT revealed local recurrence in 24.7% of patients (n = 62). Lymph node metastases were present in the pelvis in 40.6% of patients (n = 102), in the retroperitoneum in 19.5% of patients (n = 49), and in supradiaphragmatic locations in 12.0% of patients (n = 30). Bone and visceral metastases were detected in 40.2% of patients (n = 101) and in 3.6% of patients (n = 9), respectively. In tumors with higher Gleason scores (≤7 vs. ≥8), detection efficacy trended higher (76.3% vs. 86.7%) but was not statistically significant (P = 0.32). However, detection efficacy was higher in patients who had received ADT (91.7% vs. 78.0%) within 6 mo before imaging (P = 0.0179). Conclusion: 18F-PSMA-1007 PET/CT offers high detection rates for BCR after radical prostatectomy that are comparable to or better than those published for 68Ga-labeled PSMA ligands.
Keywords: 18F-PSMA-1007; PET/CT; hybrid imaging; prostate cancer; biochemical recurrence
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Journal of Nuclear Medicine 60(2019), 362-368
Online First (2018) DOI: 10.2967/jnumed.118.212233
Cited 246 times in Scopus -
Lecture (Conference)
Annual Congress of the European Association of Nuclear Medicine, October 13 – 17, 2018, Düsseldorf, Germany, 13.-17.10.2018, Düsseldorf, Deutschland
DOI: 10.1007/s00259-018-4148-3
Cited 6 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31200
High management impact of Ga-68 DOTATATE (GaTate) PET/CT for imaging neuroendocrine and other somatostatin expressing tumours
Hofman, M. S.; Kong, G.; Neels, O.; Eu, P.; Hong, E.; Hicks, R. J.
Abstract
Introduction: Ga-68 DOTATATE (Ga-octreotate, GaTate) positron emission tomography (PET)/CT has multiple advantages compared with conventional and In-111 octreotide imaging for neuroendocrine tumours and other somatostatin-receptor expressing tumours. This study assesses the management impact of incremental diagnostic information obtained from this technique compared with conventional staging. Methods: Fifty-nine GaTate PET/CT studies were performed over an 18-month period (52 proven or suspected gastro-entero-pancreatic or bronchial neuroendocrine tumours and seven neural crest/mesenchymal tumours). A retrospective blinded review was performed on the number of abnormalities (1, 2–5 or >5) within defined regions with comparison to conventional imaging to assess incremental diagnostic information. Subsequent management impact (high, moderate or low) was determined by clinical review and follow up to assess pre-PET stage, treatment intent and post-PET management change. Results: Eighty-eight percent of GaTate studies were abnormal. Compared with conventional and In-111 octreotide imaging, additional information was provided by GaTate PET/CT in 68 and 83% of patients, respectively. Management impact was high (inter-modality change) in 47%, moderate (intra-modality change) in 10% and low in 41% (not assessable in 2%). High management impact included directing patients to curative surgery by identifying a primary site and directing patients with multiple metastases to systemic therapy. Conclusion: GaTate PET/CT imaging provides additional diagnostic information in a high proportion of patients with consequent high management impact. GaTate PET/CT could replace 1In-111 octreotide scintigraphy at centres where it is available given its superior accuracy, faster acquisition and lower radiation exposure. Rapid implementation could be achieved by allowing substitutional funding in the Medicare Benefit Schedule.
Keywords: DOTATATE; Ga-68; octreoscan; octreotate; PET/CT; somatostatin-receptor imaging
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Journal of Medical Imaging and Radiation Oncology 56(2012), 40-47
DOI: 10.1111/j.1754-9485.2011.02327.x
Cited 204 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31199
Laboratory Study of Bilateral Supernova Remnants and Continuous MHD Shocks
Mabey, P.; Albertazzi, B.; Rigon, G.; Marquès, J. R.; Palmer, C. A. J.; Topp-Mugglestone, J.; Perez-Martin, P.; Kroll, F.; Brack, F.-E.; Cowan, T.; Schramm, U.; Falk, K.; Gregori, G.; Falize, E.; Koenig, M.
Abstract
Many supernova remnants (SNRs), such as G296.5+10.0, exhibit an axisymmetric or barrel shape. Such morphologies have previously been linked to the direction of the Galactic magnetic field, although this remains uncertain. These SNRs generate magnetohydrodynamic shocks in the interstellar medium, modifying its physical and chemical properties. The ability to study these shocks through observations is difficult due to the small spatial scales involved. In order to answer these questions, we perform a scaled laboratory experiment in which a lasergenerated blast wave expands under the influence of a uniform magnetic field. The blast wave exhibits a spheroidal shape, whose major axis is aligned with the magnetic field, in addition to a more continuous shock front. The implications of our results are discussed in the context of astrophysical systems.
Keywords: Supernova remnants (1667); Shocks (2086); Magnetic fields (994); Astrophysical magnetism (102); Magnetohydrodynamics (1964); Galaxy magnetic fields (604); Interstellar magnetic fields (845)
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Astrophysical Journal 896(2020), 2
DOI: 10.3847/1538-4357/ab92a4
Cited 6 times in Scopus
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Permalink: https://www.hzdr.de/publications/Publ-31198
Preclinical characterization of 18F-D-FPHCys, a new amino acid-based PET tracer
Denoyer, D.; Kirby, L.; Waldeck, K.; Roselt, P.; Neels, O.; Bourdier, T.; Shepherd, R.; Katsifis, A.; Hicks, R. J.
Abstract
Purpose The imaging potential of a new 18F-labelled methionine derivative, S-(3-[18F]fluoropropyl)-D-homocysteine (18F-D-FPHCys), and its selectivity for amino acid transporter subtypes were investigated in vitro and by imaging of human tumour xenografts. Methods Expression of members of the system L (LAT isoforms 1–4 and 4F2hc) and ASCT (ASCT isoforms 1 and 2) amino acid transporter subclasses were assessed by quantitative real-time PCR in four human tumour models, including A431 squamous cell carcinoma, PC3 prostate cancer, and Colo 205 and HT-29 colorectal cancer lines. The first investigations for the characterization of 18F-D-FPHCys were in vitro uptake studies by comparing it with [1-14C]-L-methionine (14C-MET) and in vivo by PET imaging. In addition, the specific involvement of LAT1 transporters in 18F-DFPHCys accumulation was tested by silencing LAT1 mRNA transcription with siRNAs. To determine the proliferative activity in tumour xenografts ex vivo, Ki-67 staining was used as a biomarker. Results A431 cells showed the highest 18F-D-FPHCys uptake in vitro and in vivo followed by Colo 205, PC3 and HT-29. A similar pattern of retention was observed with 14C-MET. 18F-D-FPHCys retention was strongly correlated with LAT1 expression both in vitro R2=0.85) and in vivo (R2=0.99). Downregulation of LAT1 by siRNA inhibited 18F-DFPHCys uptake, demonstrating a clear dependence on this transporter for tumour uptake. Furthermore, 18F-D-FPHCys accumulation mirrored cellular proliferation. Conclusion The favourable properties of 18F-D-FPHCys make this tracer a promising imaging probe for detection of tumours as well as for the noninvasive evaluation and monitoring of tumour growth.
Keywords: S-(3-[18F]fluoropropyl)-D-homocysteine; LAT1 amino acid transporter; In vitro uptake; Small-animal PET; Cancer imaging
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European Journal of Nuclear Medicine and Molecular Imaging 39(2011), 703-712
DOI: 10.1007/s00259-011-2017-4
Cited 9 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31197
High throughput static and dynamic small animal imaging using clinical PET/CT: potential preclinical applications
Aide, N.; Desmonts, C.; Beauregard, J.-M.; Beyer, T.; Kinross, K.; Roselt, P.; Neels, O.; Agostini, D.; Bardet, S.; Bouvard, G.; Hicks, R. J.
Abstract
Purpose The objective of the study was to evaluate state-of-the-art clinical PET/CT technology in performing static and dynamic imaging of several mice simultaneously. Methods A mouse-sized phantom was imaged mimicking simultaneous imaging of three mice with computation of recovery coefficients (RCs) and spillover ratios (SORs). Fifteen mice harbouring abdominal or subcutaneous tumours were imaged on clinical PET/CT with point spread function (PSF) reconstruction after injection of [18F]fluorodeoxyglucose or [18F]fluorothymidine. Three of these mice were imaged alone and simultaneously at radial positions –5, 0 and 5 cm. The remaining 12 tumour-bearing mice were imaged in groups of 3 to establish the quantitative accuracy of PET data using ex vivo gamma counting as the reference. Finally, a dynamic scan was performed in three mice simultaneously after the injection of 68Ga-ethylenediaminetetraacetic acid (EDTA). Results For typical lesion sizes of 7–8 mm phantom experiments indicated RCs of 0.42 and 0.76 for ordered subsets expectation maximization (OSEM) and PSF reconstruction, respectively. For PSF reconstruction, SORair and SORwater were 5.3 and 7.5%, respectively. A strong correlation (r2=0.97, p<0.0001) between quantitative data obtained in mice imaged alone and simultaneously in a group of three was found following PSF reconstruction. The correlation between ex vivo counting and PET/CT data was better with PSF reconstruction (r2=0.98; slope=0.89, p<0.0001) than without (r2=0.96; slope=0.62, p<0.001). Valid time-activity curves of the blood pool, kidneys and bladder could be derived from 68Ga-EDTA dynamic acquisition.Conclusion New generation clinical PET/CT can be used for simultaneous imaging of multiple small animals in experiments requiring high throughput and where a dedicated small animal PET system is not available.
Keywords: Molecular imaging; PET/CT; PSF reconstruction; Cancer research; Preclinical studies
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European Journal of Nuclear Medicine and Molecular Imaging 37(2010), 991-1001
DOI: 10.1007/s00259-009-1352-1
Cited 31 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31196
High-Contrast PET of Melanoma Using 18F-MEL050, a Selective Probe for Melanin with Predominantly Renal Clearance
Denoyer, D.; Greguric, I.; Roselt, P.; Neels, O.; Aide, N.; Taylor, S. R.; Katsifis, A.; Dorow, D. S.; Hicks, R. J.
Abstract
The aim of this study was to evaluate the novel probe 18F-6-fluoro-N-[2-(diethylamino)ethyl] pyridine-3-carboxamide (18F-MEL050) for the imaging of primary and metastatic melanoma. Methods: PET using 18F-MEL050 was performed in murine models of melanoma. The specificity of 18F-MEL050 was studied by comparing its accumulation in pigmented B16-F0 allograft tumors with that of human amelanotic A375 xenografts using PET and high-resolution autoradiography. 18F-MEL050 PET results were compared with 18F-FDG PET, the current standard in melanoma molecular imaging. To test the ability of 18F-MEL050 to assess the metastatic spread of melanoma, a murine model of lung metastasis was imaged by PET/CT, and results correlated with physical assessment of tumor burden in the lungs. Results: In pigmented B16-F0 grafts, 18F-MEL050 PET yielded a tumor-to-background ratio of approximately 20:1 at 1 h and greater than 50:1 at 2 and 3 h. In the B16-F0 melanoma allograft model, tumor-to-background ratio was more than 9-fold higher for 18F-MEL050 than for 18F-FDG (50.9 ± 6.9 vs. 5.8 ± 0.5). No uptake was observed in the amelanotic melanoma xenografts. Intense uptake of 18F-MEL050 was evident in metastatic lesions in the lungs of B16-BL6 tumor–bearing mice on PET at 2 h after tracer injection, with high concordance between 18F-MEL050 accumulation on PET/CT and tumor burden determined at necroscopy. Conclusion: 18F-MEL050 has a rapid tumor uptake and high retention with specificity for melanin, suggesting great potential for noninvasive clinical evaluation of suspected metastatic melanoma.
Keywords: melanoma imaging; small-animal PET; PET/CT; high-resolution autoradiography; fluoronicotinamide analogue
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Journal of Nuclear Medicine 51(2010), 441-447
DOI: 10.2967/jnumed.109.070060
Cited 55 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31195
Discovery of [18F]N-(2-(Diethylamino)ethyl)-6-fluoronicotinamide: A Melanoma Positron Emission Tomography Imaging Radiotracer with High Tumor to Body Contrast Ratio and Rapid Renal Clearance
Greguric, I.; Taylor, S. R.; Denoyer, D.; Ballantyne, P.; Berghofer, P.; Roselt, P.; Pham, T. Q.; Mattner, F.; Bourdier, T.; Neels, O.; Dorow, D. S.; Loch, C.; Hicks, R. J.; Katsifis, A.
Abstract
The high melanoma uptake and rapid body clearance displayed by our series of [123I]iodonicotinamides prompted the development of [18F]N-(2-(diethylamino)ethyl)-6-fluoronicotinamide ([18F]2), a novel radiotracer for PET melanoma imaging. Significantly, unlike fluorobenzoates, [18F]fluorine incorporation on the nicotinamide ring is one step, facile, and high yielding. [18F]2 displayed high tumor uptake, rapid body clearance via predominantly renal excretion, and is currently being evaluated in preclinical studies for progression into clinical trials to assess the responsiveness of therapeutic agents.
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Journal of Medicinal Chemistry 52(2009), 5299-5302
DOI: 10.1021/jm9008423
Cited 51 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31194
High-Performance Bismuth-Doped Nickel Aerogel Electrocatalyst for the Methanol Oxidation Reaction
Dubale, A. A.; Zheng, Y.; Wang, H.; Hübner, R.; Li, Y.; Yang, J.; Zhang, J.; Sethi, N. K.; He, L.; Zheng, Z.; Liu, W.
Abstract
Low-cost, non-noble-metal electrocatalysts are required for direct methanol fuel cells, but their development has been hindered by limited activity, high onset potential, low conductivity, and poor durability. A surface electronic structure tuning strategy is presented, which involves doping of a foreign oxophilic post-transition metal onto transition metal aerogels to achieve a non-noble-metal aerogel Ni97Bi3 with unprecedented electrocatalytic activity and durability in methanol oxidation. Trace amounts of Bi are atomically dispersed on the surface of the Ni97Bi3 aerogel, which leads to an optimum shift of the d-band center of Ni, large compressive strain of Bi, and greatly increased conductivity of the aerogel. The electrocatalyst is endowed with abundant active sites, efficient electron and mass transfer, resistance to CO poisoning, and outstanding performance in methanol oxidation. This work sheds light on the design of high-performance non-noble-metal electrocatalysts
Keywords: aerogels; bismuth dopants; methanol oxidation; nickel; single atoms
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 31193) publication
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Angewandte Chemie - International Edition 59(2020), 13891-13899
DOI: 10.1002/anie.202004314
Cited 192 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31193
Birefringence in thermally anisotropic relativistic plasmas and its impact on laser-plasma interactions
Arefiev, A. V.; Stark, D. J.; Toncian, T.; Murakami, M.
Abstract
One of the paradigm-shifting phenomena triggered in laser-plasma interactions at relativistic intensities is the so-called relativistic transparency. As the electrons become heated by the laser to relativistic energies, the plasma becomes transparent to the laser light even though the plasma density is sufficiently high to reflect the laser pulse in the non-relativistic case. This paper highlights the impact that relativistic transparency can have on laser-matter interactions by focusing on a collective phenomenon that is associated with the onset of relativistic transparency: plasma birefringence in thermally anisotropic relativistic plasmas. The optical properties of such a system become dependent on the polarization of light, and this can serve as the basis for plasma-based optical devices or novel diagnostic capalibities.
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Physics of Plasmas 27(2020)6, 063106
DOI: 10.1063/5.0008018
Cited 7 times in Scopus -
Contribution to WWW
arXiv:2005.12435 [physics.plasm-ph]: https://arxiv.org/abs/2005.12435
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Permalink: https://www.hzdr.de/publications/Publ-31191
Power Scaling for Collimated γ-Ray Beams Generated by Structured Laser-Irradiated Targets and Its Application to Two-Photon Pair Production
Wang, T.; Ribeyre, X.; Gong, Z.; Jansen, O.; D'Humières, E.; Stutman, D.; Toncian, T.; Arefiev, A.
Abstract
Using three-dimensional kinetic simulations, we examine the emission of collimated γ-ray beams from structured laser-irradiated targets with a prefilled cylindrical channel and its scaling with laser power (in the multi-PW range). The laser power is increased by increasing the laser energy and the size of the focal spot while keeping the peak intensity fixed at 5×1022W/cm2. The channel radius is increased proportionally to accommodate the change in laser spot size. The efficiency of conversion of the laser energy into a beam of MeV-level γ rays (with a 10âˆ&tild; opening angle) increases rapidly with the incident laser power P before it roughly saturates above P≈4PW. Detailed particle tracking reveals that the power scaling is a result of enhanced electron acceleration at higher laser powers. One application that directly benefits from such a strong scaling is pair production via two-photon collisions. We investigate two schemes for generating pairs through the linear Breit-Wheeler process: Colliding two γ-ray beams and colliding one γ-ray beam with black-body radiation. The two scenarios project up to 104 and 105 pairs, respectively, for the γ-ray beams generated at P=4PW. A comparison with a regime of laser-irradiated hollow channels corroborates the robustness of the setup with prefilled channels.
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Physical Review Applied 13(2020)5, 054024
DOI: 10.1103/PhysRevApplied.13.054024
Cited 49 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31190
Direct laser ion acceleration and above-threshold ionization at intensities from 1021 W/cm2 to 3×1023 W/cm2
Yandow, A.; Toncian, T.; Ditmire, T.
Abstract
Calculations on the dynamics of ions and electrons in near-infrared laser fields at intensities up to 3×1023W/cm2 are presented. We explore the acceleration of ions in a laser focus by conservation of canonical momentum during ionization events and by the ponderomotive force in the f/1 focal geometry required to reach such intensity. At intensities exceeding 1023W/cm2, highly charged ions are expelled from the laser focus before they can interact with the laser pulse at peak intensity, decreasing the predicted ionization yields of deeply bound states. We consider the interaction of a tightly focused, f/1 laser pulse with krypton at an intensity of 3×1023W/cm2 and a pulse duration of 140 fs. We find that the ions and electrons are accelerated to energies in excess of 2 MeV/nucleon and 1.4 GeV, respectively. Ponderomotive expulsion of the parent ions decreases the total number of ultrarelativistic above-threshold ionization electrons produced by tunneling ionization from the K-shell states of krypton but does not change their energy spectrum.
Viele Grüße
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Physical Review A 100(2019)5, 053406
DOI: 10.1103/PhysRevA.100.053406
Cited 6 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31189
ARCTURUS laser: A versatile high-contrast, high-power multi-beam laser system
Cerchez, M.; Prasad, R.; Aurand, B.; Giesecke, A. L.; Spickermann, S.; Brauckmann, S.; Aktan, E.; Swantusch, M.; Toncian, M.; Toncian, T.; Willi, O.
Abstract
With the latest configuration, the Ti:Sa laser system ARCTURUS (Düsseldorf University, Germany) operates with a double-chirped pulse amplification (CPA) architecture delivering pulses with an energy of 7 J before compression in each of the two high-power beams. By the implementation of a plasma mirror system, the intrinsic laser contrast is enhanced up to on a time scale of hundreds of picoseconds, before the main peak. The laser system has been used in various configurations for advanced experiments and different studies have been carried out employing the high-power laser beams as a single, high-intensity interaction beam (), in dual- and multi-beam configurations or in a pump-probe arrangement.
Keywords: high power laser pulses; laser driven particle and radiation sources; multi-beam configuration; relativistic plasmas; Ti:Sa lasers
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High Power Laser Science and Engineering 7(2019), e37
DOI: 10.1017/hpl.2019.21
Cited 18 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31188
A multihertz, kiloelectronvolt pulsed proton source from a laser irradiated continuous hydrogen cluster target
Aurand, B.; Grieser, S.; Toncian, T.; Aktan, E.; Cerchez, M.; Lessmann, L.; Prasad, R.; Khoukaz, A.; Willi, O.
Abstract
A high-repetition rate laser-driven proton source from a continuously operating cryogenic hydrogen cluster target is presented. We demonstrate a debris-free, Coulomb-explosion based acceleration in the 10s of kilo-electron-volt range with a stability of about 10% in a 5 Hz operation. This acceleration mechanism, delivering short pulse proton bursts, represents an ideal acceleration scheme for various applications, for example, in materials science or as an injector source in conventional accelerators. Furthermore, the proton energy can be tuned by varying the laser and/or cluster parameters. 3D numerical particle-in-cell simulations and an analytical model support the experimental results and reveal great potential for further studies, scaling up the proton energies, which can be realized with a simple modification of the target.
Viele Grüße
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Physics of Plasmas 26(2019)7, 073102
DOI: 10.1063/1.5093287
Cited 4 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31187
Beam distortion effects upon focusing an ultrashort petawatt laser pulse to greater than 1022 W/cm2
Tiwari, G.; Gaul, E.; Martinez, M.; Dyer, G.; Gordon, J.; Spinks, M.; Toncian, T.; Bowers, B.; Jiao, X.; Kupfer, R.; Lisi, L.; Mccary, E.; Roycroft, R.; Yandow, A.; Glenn, G. D.; Donovan, M.; Ditmire, T.; Hegelich, B. M.
Abstract
When an ultrashort laser pulse is tightly focused to a size approaching its central wavelength, the properties of the focused spot diverge from the diffraction-limited case. Here, we report on this change in behavior of a tightly focused petawatt-class laser beam by an f ㄍ1 off-axis parabolic mirror (OAPM). Considering the effects of residual aberration, the spatial profile of the near-field, and pointing error, we estimate the deviation in peak intensities of the focused spot from the ideal case. We verify that the estimated peak intensity values are within an acceptable error range of the measured values. With the added uncertainties in target alignment, we extend the estimation to infer on-target peak intensities of ≥1022 Wㄍcm2 for a target at the focal plane of this f ㄍ1 OAPM.
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Optics Letters 44(2019)11, 2764-2767
DOI: 10.1364/OL.44.002764
Cited 32 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31186
UV harmonics generated on modulated targets irradiated by high-intensity laser pulses
Giesecke, A. L.; Peth, C.; Toncian, T.; Willi, O.; Cerchez, M.
Abstract
The generation of high-order harmonics in ultraviolet spectral range by targets of periodic modulation interacting with relativistic, high contrast laser pulse ( 2 = 10 20 W/cm 2 · μm 2 ) was investigated experimentally and numerically. The spectral intensity of the 2nd- and 3rd-order harmonic emission from grating of different periodicities (250, 410, and 480 nm) is presented. The enhancement of the 3rd harmonic order compared with 2nd was observed for a grating of 480 nm periodicity. The experimental results indicate the role of the grating periodicity on the emission efficiency of different higher order harmonics in the UV spectral range. The higher order harmonics are emitted at the grating surface separated from the specular reflection of the laser pulse, due of the interference effects. In addition, 2D numerical PIC simulations demonstrate a complex angular distribution of the higher harmonics (HH) spectral intensity and confirm the strong dependence of the HH efficiency of a specific order on the grating periodicity, as observed experimentally. These special features of the high harmonic emission by periodically modulated targets open the route toward the control of HH spectral composition and of the emission efficiency of the lower order harmonics. Copyright © Cambridge University Press 2019.
Keywords: high harmonic generation; High-density plasma; Laser-driven radiation source
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Laser and Particle Beams 37(2019)1, 12-17
DOI: 10.1017/S0263034619000090
Cited 4 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31185
Structured targets for detection of Megatesla-level magnetic fields through Faraday rotation of XFEL beams
Wang, T.; Toncian, T.; Wei, M. S.; Arefiev, A. V.
Abstract
A solid density target irradiated by a high-intensity laser pulse can become relativistically transparent, which then allows it to sustain an extremely strong laser-driven longitudinal electron current. The current generates a filament with a slowly varying MT-level azimuthal magnetic field that has been shown to prompt efficient emission of multi-MeV photons in the form of a collimated beam required for multiple applications. This work examines the feasibility of using an x-ray beam from the European x-ray free electron laser for the detection of the magnetic field via the Faraday rotation. Post-processed three dimensional particle-in-cell simulations show that, even though the relativistic transparency dramatically reduces the rotation in a uniform target, the detrimental effect can be successfully reversed by employing a structured target containing a channel to achieve a rotation angle of 10-4rad. The channel must be relativistically transparent with an electron density that is lower than the near-solid density in the bulk. The detection setup has been optimized by varying the channel radius and focusing the laser pulse driving the magnetic field. We predict that the Faraday rotation can produce 103 photons with polarization orthogonal to the polarization of the incoming 100 fs long probe beam with 5 × 1012 x-ray photons. Based on the calculated rotation angle, the polarization purity must be much better than 10-8 in order to detect the signal above the noise level.
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Physics of Plasmas 25(2019), 013105
DOI: 10.1063/1.5066109
Cited 17 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31184
Microstructure and fracture toughness characterization of three 9Cr ODS EUROFER steels with different thermo-mechanical treatments
Das, A.; Chekhonin, P.; Altstadt, E.; Mcclintock, D.; Bergner, F.; Heintze, C.; Lindau, R.
Abstract
Ferritic martensitic ODS steels are one of the candidate structural materials for future Gen-IV nuclear fission and fusion reactors. The dependence of fracture toughness on microstructure was investigated by comparing three 9Cr ODS EUROFER steels manufactured through different thermo-mechanical processing routes. Quasi-static fracture toughness testing was performed with sub-sized C(T) specimens and microstructural characterization was carried out using scanning electron microscopy, electron backscatter diffraction, and transmission electron microscopy. It was found that at lower test temperatures (-100 to 22 °C), the fracture toughness was primarily controlled by crack initiation at sub-micron particles and by production of secondary cracks during fracture. At higher temperatures (above 100 °C), fracture toughness was predominantly controlled by the matrix ductility and the grain boundary strength with a relatively ductile coarse-grained alloy demonstrating higher fracture toughness compared to high-strength fine-grained alloys. These results and discussion show that slight variations in thermomechanical treatments can produce significant differences in microstructure and fracture toughness behaviour of ferritic martensitic ODS steels.
Keywords: ODS steel; ferritic martensitic alloys; microstructure characterization; fracture toughness; structure-property relationship
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
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- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 31183) publication
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Journal of Nuclear Materials 542(2020), 152464
DOI: 10.1016/j.jnucmat.2020.152464
Cited 10 times in Scopus
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- Final Draft PDF 2,7 MB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-31183
High PerformanceComputing: 35th International Conference, ISC High Performance 2020
Sadayappan, P.; Chamberlain, B. L.; Juckeland, G.; Ltaief, H.
Abstract
This book constitutes the refereed proceedings of the 35th International Conference on High Performance Computing, ISC High Performance 2020, held in Frankfurt/Main, Germany, in June 2020.*
The 27 revised full papers presented were carefully reviewed and selected from 87 submissions. The papers cover a broad range of topics such as architectures, networks & infrastructure; artificial intelligence and machine learning; data, storage & visualization; emerging technologies; HPC algorithms; HPC applications; performance modeling & measurement; programming models & systems software.
*The conference was held virtually due to the COVID-19 pandemic.
Keywords: artificial intelligence; computer hardware; computer networks; computer programming; computer systems; distributed computer systems; microprocessor chips; parallel algorithms; parallel architectures; parallel processing
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Book (Editorship)
Cham: Springer, 2020
556 Seiten
ISBN: 978-3-030-50742-8
DOI: 10.1007/978-3-030-50743-5
Permalink: https://www.hzdr.de/publications/Publ-31181
P1802 - Universal Building Blocks for Radiolabeling
Abstract
The present invention describes novel chelators (multidentate ligands) and precompounds for complexation of radiometals and non-radioactive counterparts, for use in radiopharmacy. The invention includes a process and a kit involving such chelators.
Active moieties directing to a pharmaceutical target (such as peptides or proteins) can be attached to the chelator very easily via the so called “click-chemistry” forming a triazole-ring moiety. The aromatic triazole-nitrogen itself acts as a new and “soft” nucleophilic site enabling for complexation of various radiometals or non-radioactive counterparts. The chelators are capable of fast complexation at low temperature.
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Patent
PCT/EP2019/054954 - Offenlegung 06.09.2019; Nachanmeldungen: EP
Permalink: https://www.hzdr.de/publications/Publ-31180
P1801 - Method for the preparation of nanoscale DNA-encircled lipid bilayers
Abstract
The present invention relates to a method for the preparation of nanoscale nucleic acid-encircled lipid bilayers, the nanoscale nucleic acid-encircled lipid bilayers and their use.
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Patent
PCT/EP2019/054271 - Offenlegung 29.08.2019; Nachanmeldungen: EP
Permalink: https://www.hzdr.de/publications/Publ-31179
P1714 - Verfahren zur Trennung von Mineralien
Babel, B. M.; Kupka, N.; Rudolph, M.
Abstract
Die Erfindung betrifft ein Verfahren zur Trennung von Mineralien aus Mineralgemengen mittels Flotation unter Verwendung eines Drückers. Dabei ist vorgesehen, dass kolloidales Siliciumdioxid einem wässerigen, das Mineralgemenge enthaltenden Gemisch als Drücker zugesetzt wird.
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Patent
DE102017129673 - Erteilung 13.12.2018
Permalink: https://www.hzdr.de/publications/Publ-31178
P1713 - Verfahren zum Herstellen eines Probenpräparats, Probenpräparat und Verfahren zum Untersuchen eines Probenmaterials
Bartzsch, A.; Gilbricht, S.; Bachmann, K.; Heinig, T.
Abstract
Die Erfindung betrifft ein Verfahren zum Herstellen eines Probenpräparats, ein Probenpräparat und ein Verfahren zum Untersuchen eines Probenmaterials, wobei das Probenpräparat zur Untersuchung eines granularen Probenmaterials dient und herstellbar ist, indem das granulare Probenmaterial mit einem flüssigen ersten Einbettmaterial vermengt wird, das Einbettmaterial unter Ausbildung eines Vorpräparats verfestigt wird und unter Ausbildung von Trennflächen in mehrere Teilstücke zertrennt wird, die Teilstücke mit mehreren Trennflächen in einer gemeinsamen Ebene liegend in einem flüssigen zweiten Einbettmaterial eingebettet werden, und das zweite Einbettmaterial verfestigt wird.
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Patent
DE102017128355 - Erteilung 17.01.2019
Permalink: https://www.hzdr.de/publications/Publ-31177
P1712 - Method for determining the level of molten magnesium in a titanium reduction cell
Stefani, F.; Krauter, N.; Wondrak, T.; Gundrum, T.; Eckert, S.
Abstract
FIELD: metallurgy. SUBSTANCE: invention relates to the metallurgy industry. Magnesium level and the skull characteristics in the titanium reduction reactor determining method, based on the EMF measurements in the receiving coil, induced by the electromagnetic field from located around the retort the exciting windings set, contains the steps, on which for the determination currents of different frequencies are used, at that, first, by the electrodynamics equations numerical solving, developing the reference base of the EMF calculated values in the located above the reactor receiving coil, with the molten magnesium different specified levels, different titanium skull given positions and sizes for the supply current given set of frequencies in the range of 1–50 Hz, and then, in the process of titanium reduction, with the same set of current parameters in the excitation coils, measuring the EMF values in the receiving coil, which are compared with the reference ones, and the least standard deviation is determined by the smallest standard deviation method, and the molten magnesium level, the titanium skull position and size are judged by it. EFFECT: increase in the molten metal level determining accuracy and the expansion in the method possibilities. 5 cl, 13 dwg
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Patent
RU2676845 - Erteilung 11.01.2019
Permalink: https://www.hzdr.de/publications/Publ-31176
P1711 - Peptid-Trägermaterialien als biofunktionalisierte Sammler
Lederer, F.; Pollmann, K.; Rudolph, M.
Abstract
Die Erfindung betrifft ein Verfahren zur selektiven Abtrennung von Submikro- oder Mikropartikeln mittels eines biofunktionalisierten Sammlers, ein biofunktionalisierter Sammler umfassend mindestens ein selektiv bindendes Peptid, ein selektiv bindendes Peptid und die Verwendung eines Verfahrens oder eines biofunktionalisierten Sammlers zur Gewinnung oder Rückgewinnung von Submikro- oder Mikropartikeln.
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Patent
DE102017219800 - Offenlegung 09.05.2019
Permalink: https://www.hzdr.de/publications/Publ-31175
P1710 - 4-(Furan-2-yl)-1H-pyrazolo[3,4-d]pyrimidin-6-amin-Derivate und deren Verwendung
Moldovan, R.-P.; Lai, T. H.; Schröder, S.; Dukic-Stefanovic, S.; Deuther-Conrad, W.; Brust, P.; Fischer, S.; Ludwig, F.-A.
Abstract
Die Erfindung betrifft eine Verbindung der allgemeinen Formel I worin eine Phenylgruppe oder eine Pyridylgruppe ist, R1 aus der Gruppe ausgewählt ist, die aus Wasserstoff, Halogen und -CN besteht; R2 aus der Gruppe ausgewählt ist, die aus Fluor, einer fluorierten Alkylgruppe mit 1 bis 12 Kohlenstoffatomen, einer fluorierten Alkoxygruppe mit 1 bis 12 Kohlenstoffatomen und einer fluorierten Ethergruppe besteht; Z -(CH2)n- oder -(CH2)m-C(O)-(CH2)p- ist, wobei n eine Ganzzahl von 1 bis 12 ist und wobei m und p gleich oder verschieden sein können und jeweils 0 oder eine Ganzzahl von 1 bis 12 sind.
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Patent
DE102017125533 - Offenlegung 02.05.2019; Nachanmeldungen: WO
Permalink: https://www.hzdr.de/publications/Publ-31174
P1709 - Vorrichtung und Verfahren zum Erzeugen von Ionenpulsen
Wilhelm, R. A.; Klingner, N.; Facsko, S.
Abstract
Die Erfindung betrifft eine Vorrichtung und ein Verfahren zum Erzeugen von Ionenpulsen, insbesondere von ultrakurzen Ionenpulsen, wobei die Vorrichtung eine Vakuumkammer, eine in der Vakuumkammer angeordnete Kathode, einen Laser zum Erzeugen von Laserpulsen, die auf die Kathode auftreffen und aus dieser Elektronen herauslösen, eine erste Beschleunigungseinrichtung zum Beschleunigen der Elektronen unter Erzeugung von Ionenpulsen in ein Ionisationsvolumen, eine Zuführeinrichtung zum Zuführen einer zu ionisierenden Substanzen das Ionisationsvolumen und eine zweite Beschleunigungseinrichtung zum Beschleunigen der Ionen unter Ausbildung von Ionenpulsen aus dem Ionisationsvolumen heraus aufweist.
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Patent
DE102017218456 - Erteilung 22.11.2018
Permalink: https://www.hzdr.de/publications/Publ-31173
P1708 - Justiereinrichtung
Bartheld, U.
Abstract
Die Erfindung betrifft eine Justiereinrichtung zur räumlichen Lageeinstellung eines Objekts (4), umfassend eine 10 Mehrzahl übereinander angeordneter Plattenelemente (11,12,13,14), die an einander zugewandten Seiten ineinandergreifende Radialführungsstrukturen (21,22) aufweisen, wobei auf einer Grundplatte (11) zumindest ein Paar von Verschiebungsplatten (12) und ein Paar von 15 Neigungsplatten (13) angeordnet sind, wobei Verschiebungsplatten (12) eine konstante Dicke aufweisen und ihre jeweilige obere Radialführungsstruktur (21) und untere Radialführungsstruktur (22) exzentrisch versetzt zueinander angeordnet sind und Neigungsplatten (13) eine variable Dicke 20 aufweisen und ihre jeweilige obere Radialführungsstruktur (21) und untere Radialführungsstruktur (22) konzentrisch zueinander angeordnet sind.
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Patent
DE102017123920 - Erteilung 20.12.2018; Nachanmeldungen: WO, US
Permalink: https://www.hzdr.de/publications/Publ-31172
P1707 - 3-Methylbenzo[e]imidazo[5,1-c][1,2,4]triazin-Derivate zur Verwendung als Inhibitoren von Phosphodiesterase 2A
Scheunemann, M.; Ritawidya, R.; Brust, P.; Schröder, S.
Abstract
Die Erfindung betrifft eine Verbindung der allgemeinen Formel I oder ein pharmazeutisch akzeptables Salz davon, wobei A1, A2 und A3 unabhängig voneinander jeweils CH oder N sind; R1 -OR2 oder eine (3-Methyloxetan-3-yl)methyloxy-Gruppe ist, wobei R2 eine substituierte oder unsubstituierte Alkylgruppe mit 1 bis 12 Kohlenstoffatomen ist; X1 aus der Gruppe ausgewählt ist, die aus Wasserstoff, Halogen, Methyl -NO2 und einer kationischen Trialkylammoniumgruppe besteht; X2 aus der Gruppe ausgewählt ist, die aus Halogen, -NO2, einer Boronsäureester-Gruppe, einer Aryliodonium-Gruppe und einer spirocyclischen Iodoniumylid-Gruppe besteht, wobei die Boronsäureester-Gruppe eine Boronsäurepinakolester-Gruppe ist.
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Patent
DE102017119516 - Offenlegung 28.02.2019
Permalink: https://www.hzdr.de/publications/Publ-31171
P1705 - Wärmeübertrager
Abstract
Die Erfindung betrifft einen Wärmeübertrager mit wenigstens einer Trennwand und von wenigstens einer Seite der Trennwand abstehenden und die Oberfläche der Trennwand vergrößernden Oberflächenelementen, die von einem Fluid umströmbar sind. Es ist die Aufgabe der vorliegenden Erfindung, massearme Wärmeübertrager mit großer thermischer Übertragungsleistung vorzuschlagen. Diese Aufgabe wird durch einen Wärmeübertrager gelöst, bei dem die Oberflächenelemente flossenartig von der Trennwand abstehend ausgebildet sind und die Oberflächenelemente Verstärkungswülste aufweisen, wobei sich die Verstärkungswülste bis zu der Trennwand hin erstrecken.
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Patent
DE102017214261 - Offenlegung: 21.02.2019; Nachanmeldungen: WO, EP, JP, US
Permalink: https://www.hzdr.de/publications/Publ-31170
P1704 - Vorrichtung, Anordnung und Verfahren zum Charakterisieren der Torsion, der Rotation und/oder der Positionierung einer Welle
Buchenau, D.
Abstract
Die Erfindung betrifft eine Vorrichtung, eine Anordnung und ein Verfahren zum Charakterisieren der Torsion, Rotation und/oder Positionierung einer Welle, wobei von einem zwischen mindestens zwei Magnetfelddetektoren angeordneten Magnetfelderzeuger mittels eines periodischen Erregersignals ein periodisches Magnetfeld erzeugt wird, das von der Welle modifiziert wird und an jedem der Magnetfelddetektoren ein Ausgangssignal hervorruft, wobei die amplitudenmäßige oder phasenmäßige Differenz zwischen dem Erregersignal und dem ersten Ausgangssignal als erste Messgröße und zwischen dem Erregersignal und dem zweiten Ausgangssignal als zweite Messgröße erfasst wird, die Summe und/oder die Differenz der ersten und der zweiten Messgröße gebildet wird, und basierend darauf die Torsion, Rotation und/oder Positionierung der Welle charakterisiert wird.
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Patent
DE102017111055 - Erteilung 06.09.2018; Nachanmeldungen: WO, CN, EP, US
Permalink: https://www.hzdr.de/publications/Publ-31169
Moisture repelling perovskite nanowires for higher stability in energy applications
Rajbhar, M. K.; Das, P.; Satpati, B.; Möller, W.; Ramgir, N.; Chatterjee, S.
Abstract
Perovskite nanowires are known to be strongly interacting with the moisture. In this work, we demonstrate that strontium manganate (SrMnO3) nanowire, an oxide perovskite, which is initially superhydrophilic, becomes a water repellent upon suitable modification by the ion beam. Highly crystalline SrMnO3 nanowires have been synthesized hydrothermally with an average diameter of about 60 nm and possess 4H crystal structure. The nanowires have been systematically irradiated with nitrogen ions at different energies and in a specific range of ion fluence. For low energy (5 keV), and at a relatively high threshold ion fluence, the nanowire surface starts to become hydrophobic, and the hydrophobicity increases with the ion fluence. However, at higher energies (50–100 keV), the sample surface becomes superhydrophobic at relatively low fluence, and beyond this point, the contact angle is almost independent of the ion fluence. Using state-of-the-art TRI3DYN computer-based simulation, and by employing density functional theory based calculations, we have shown that at low ion energy, the defects turn out to be a dominating factor for the samples to become hydrophobic. At higher ion energies, nanowelding and porous structure lead the way to become superhydrophobic.
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 31168) publication
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Applied Surface Science 527(2020), 146683
DOI: 10.1016/j.apsusc.2020.146683
Cited 16 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31168
P1703 - Schichtanordnung, elektronisches Bauteil mit einer Schichtanordnung und Verwendung einer Schichtanordnung
TU Bergakademie Freiberg; Rebohle, L.
Abstract
Gemäß verschiedenen Ausführungsformen wird eine Schichtanordnung (100) bereitgestellt, welche Folgendes aufweist: eine erste Barriereschicht (102a) und eine zweite Barriereschicht (102b), wobei die beiden Barriereschichten (102a, 102b) elektrisch isolierend sind, und eine Schichtstruktur (110), welche zwischen den beiden Barriereschichten (102a, 102b) angeordnet ist und derart eingerichtet ist, dass diese mittels eines elektrischen Feldes einer ersten Polarität (311a) und mittels eines elektrischen Feldes einer der ersten Polarität entgegengesetzten zweiten Polarität (311b) remanent polarisierbar ist, wobei die Schichtstruktur (110) mindestens eine erste Ladungsspeicherschicht (104a), eine zweite Ladungsspeicherschicht (104b) und eine zwischen der ersten Ladungsspeicherschicht (104a) und der zweiten Ladungsspeicherschicht (104b) angeordnete elektrisch isolierende Tunnelbarriereschicht (106) aufweist.
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Patent
DE102017109082 - Offenlegung 31.10.2018
Permalink: https://www.hzdr.de/publications/Publ-31167
P1702 - Vorrichtung zum Charakterisieren des elektrischen Widerstandes eines Messobjekts
Abstract
Die Erfindung betrifft eine Messvorrichtung zum Charakterisieren des elektrischen Widerstandes eines Messobjekts, aufweisend eine elektrische Energiequelle mit zwei Polen, eine Spannungsmesseinrichtung mit zwei Messeingängen, vier Anschlusskontakte zum Anschließen von vier Kontaktelektroden, und eine Schalteinrichtung zum variablen paarweisen elektrischen Verbinden je eines der Pole und Messeingänge mit je einem der Anschlusskontakte unter Ausbildung unterschiedlicher Beschaltungskonfigurationen, wobei die Messvorrichtung zum Durchführen von mindestens vier Messsequenzen mit unterschiedlichen Beschaltungskonfigurationen und zum Ermitteln des Längswiderstandes des Messobjekts unter Einbeziehung von in diesen Beschaltungskonfigurationen erfassten Strom- und Spannungssignalen ausgebildet ist.
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Patent
DE102017105317 - Erteilung 09.05.2018, Nachanmeldungen: WO, CN, EP, US
Permalink: https://www.hzdr.de/publications/Publ-31166
PIConGPU setup: Gas-foil target for ion acceleration
Pausch, R.; Levy, D.; Andriyash, I.; Schultze-Makuch, A.; Bernert, C.; Zeil, K.; Bussmann, M.; Kluge, T.; Garten, M.; Steiniger, K.; Debus, A.
Abstract
This data set contains the PIConGPU source code used for the simulations presented in "Gas-foil target for ion acceleration" and the setup files.
Keywords: PIConGPU
Related publications
- DOI: 10.1088/1367-2630/abbf6d references this (Id 31165) publication
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Laser-plasma proton acceleration with a combined gas-foil target
ROBIS: 31881 has used this (Id 31165) publication of HZDR-primary research data
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Software in the HZDR data repository RODARE
Publication date: 2020-06-18 Open access
DOI: 10.14278/rodare.374
Versions: 10.14278/rodare.375
License: GPL-3.0-only
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31165
P1701 - In vivo stable Hg-197(m) compounds, method for the production thereof and use thereof in nuclear medical diagnostics and endoradionuclide therapy (theranostics)
Pietzsch, H.-J.; Walther, M.; Wünsche, T.
Abstract
The present invention relates to in vivo stable 197(m)Hg compounds according to formula (I) for use in nuclear medical diagnostics and endoradionuclide therapy (theranostics), particularly the treatment of cancer, a method for the production of the 197(m)Hg compounds comprising the step of radiolabeling of organic precursor compounds with NCA 197(m)Hg by electrophilic substitution; and the use of the 197(m)Hg compounds for nuclear medical diagnostics and endoradionuclide therapy (theranostics), particularly the treatment of cancer.
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Patent
PCT/EP2018/052996 - Offenlegung 16.08.2018, Nachanmeldungen: CA, EP, US
Permalink: https://www.hzdr.de/publications/Publ-31164
P1611 - Method and system for calibration-free determination of a flow velocity of an electrically conductive fluid
Krauter, N.; Stefani, F.; Eckert, S.; Gerbeth, G.
Abstract
The present invention refers to a method and a system for calibration-free determination of a flow velocity of an electrically conductive fluid (7). Each of two field coils (1a, 1b), which are designed to be positioned at a distance from each other in the respective fluid (7) and electrically insulated from the respective fluid (7), is provided simultaneously with a pulsed electrical current, wherein the two pulsed electrical currents are oppositely directed, so that a primary magnetic field is created leading to oppositely directed eddy currents induced by the primary magnetic field in the surrounding fluid (7), thereby creating a secondary magnetic field in the respective fluid (7). The secondary magnetic field is measured after the pulsed electrical currents by two magnetic field sensors (3a, 3b), which are designed to be positioned at a distance from each other in the respective fluid (7) and electrically insulated from the respective fluid (7), wherein the flow velocity is calculated from a measured time-dependent strength of the secondary magnetic field and/or its time derivative.
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Patent
PCT/EP2016/076967 - Offenlegung 17.05.2018; Nachanmeldungen: EP
Permalink: https://www.hzdr.de/publications/Publ-31163
P1607 - Anordnung zum Charakterisieren des Füllstandes eines elektrisch leitfähigen Materials in einem Behälter
Zürner, T.; Ratajczak, M.; Wondrak, T.; Eckert, S.
Abstract
Die Erfindung betrifft eine Anordnung zum Charakterisieren des Füllstandes eines elektrisch leitfähigen Materials in einem Behälter, aufweisend ein seitlich des Behälter-Innenraumes angeordnetes Sensorelement mit einer Erregerspule und zwei gradiometrisch verschalteten Empfängerspulen, wobei die Anordnung zum Beaufschlagen der Erregerspule mit einem Wechselstrom, zum Erfassen der an den gradiometrisch verschalteten Empfängerspulen resultierenden Ausgangsspannung, zum Ermitteln des Anteils der Ausgangsspannung ohne Phasenverschiebung zu dem Wechselstrom und/oder des Anteils der Ausgangsspannung mit einer Phasenverschiebung von 90° zu dem Wechselstrom, und zum Charakterisieren des Füllstandes basierend darauf ausgebildet ist.
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Patent
DE102016112266 - Offenlegung 11.01.2018
Permalink: https://www.hzdr.de/publications/Publ-31162
P1606 - Verfahren und Vorrichtung zu Ga-Rückgewinnung
FCM GmbH; TU Bergakademie Freiberg; Zeidler, O.
Abstract
Die vorliegende Erfindung umfasst ein Verfahren zur selektiven Abtrennung von Ga aus Ätzabwässern mit Hilfe eines Dialyseverfahrens. Hierbei wird das besondere Komplexbildungsverhaltens des Ga ausgenutzt, welches einen instabilen Tetrahalogenokomplex bildet. Dieser bildet sich nur bei ausreichend hoher Halogenidkonzentration. Da die Halogenidkonzentration über die Membran niedriger wird, zerfällt der Ga-Tetrahalogenidokomplex in der Membran, wodurch das Ga zurückgehalten wird. Andere Metalle wie In und Fe zeigen dieses Verhalten nicht, weswegen die Tetrahalogenokomplexe dieser Metalle die Membran passieren können und somit selektiv abgetrennt werden können.
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Patent
DE102016210451 - Offenlegung 14.12.2017; Nachanmeldungen: TW, WO
Permalink: https://www.hzdr.de/publications/Publ-31161
P1605 - Verfahren und Trägermaterial zur Bereitstellung von metallionenbindenden Molekülen zur Gewinnung und Rückgewinnung von Wertmetallen
Matys, S.; Pollmann, K.; Raff, J.; Lehmann, F.
Abstract
Die Erfindung betrifft ein Verfahren zur Bereitstellung von metallionenbindenden Molekülen basierend auf der Phagen-Display-Methode mittels eines planaren Trägermaterials mit immobilisierten Metallionen. Die Erfindung betrifft weiterhin ein planares Trägermaterial mit immobilisierten Metallionen, metallionenbindende Peptide erhältlich durch das erfindungsgemäße Verfahren sowie die Verwendung der metallionenbindenden Moleküle zur Gewinnung oder Rückgewinnung von Wertmetallen.
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Patent
DE102016208110 - Offenlegung 16.11.2017
Permalink: https://www.hzdr.de/publications/Publ-31160
P1604 - Verfahren und Mittel zum Betrieb eines komplementären analogen rekonfigurierbaren memristiven Widerstandsschalters sowie dessen Verwendung als künstliche Synapse
Du, N.; Li, K.; Schmidt, H.; Skorupa, I.
Abstract
Die Erfindung betrifft ein Verfahren zum Betrieb eines elektronischen memristiven Bauelementes, welches aus einem komplementären analogen rekonfigurierbaren memristiven bidirektionalen Widerstandsschalter besteht, welcher eine Dreilagenschicht und zwei Elektroden aufweist. Das erfindungsgemäße Verfahren schlägt angepasste Schreibprozesse vor, die mittels der Überlagerung von Schreibpulssequenzen die Festlegung eines Zustandspaares komplementärer Widerstandszustände realisieren. In Verbindung mit Lesepulsen angepasster Polarität kann das elektronische memristive Bauelement Fuzzy-Logik umsetzen und als künstliche Synapse mit der Realisierung aller vier Lernkurven für komplementäres Lernen betrieben werden. Eine Mehrzahl von Verwendungsmöglichkeiten des erfindungsgemäß betriebenen Bauelementes wird vorgeschlagen.
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Patent
DE102016205860 - Offenlegung: 12.10.2017; Nachanmeldungen: WO, CN, US
Permalink: https://www.hzdr.de/publications/Publ-31159
Towards 3D-Motion Tracking of Instrumented Flow Followers in Large Vessels
Buntkiel, L.; Reinecke, S.; Hampel, U.
Abstract
A concept for 3D-motion tracking of instrumented flow-following sensor particles, equipped with a gyroscope, accelerometer, magnetometer and pressure sensor, has been developed. Consisting of an error state Kalman filter (ESKF) the algorithm can track the attitude of the sensor particle in relation to a reference coordinate system permanently, even under high acceleration, which interferes the attitude estimation because it is based on measuring the gravitational acceleration. Experimental results show, that using the ESKF for attitude estimation is giving accurate results even under high body acceleration.
Keywords: error state kalman filter; motion tracking; fluid dynamics; sensor particle; soft sensor
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Contribution to proceedings
Sensor and Measurement Science International, 22.-25.06.2020, Nürnberg, Deutschland
SMSI 2020 - Measurement Science, Hannover: AMA Service GmbH, 978-3-9819376-2-6, 309-310
DOI: 10.5162/SMSI2020/E6.1
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31158
P1603 - Verfahren zur Herstellung von auf Silizium basierenden Anoden für Sekundärbatterien
TU Bergakademie Freiberg; Prucnal, S.; Skorupa, W.
Abstract
Die Erfindung betrifft ein Verfahren zur Herstellung von auf Silizium basierenden Anoden für Sekundärbatterien, wobei die Sekundärbatterien zumindest aus der Anode, aus mindestens einem Elektrolyten und einer Gegenelektrode bestehen. Dabei werden folgende Schritte zur Herstellung einer Anode (20) durchgeführt:
– Abscheiden einer Silizium-Schicht (3) auf einem Korngrenzen (2) aufweisenden Metallsubstrat (1), wobei die Silizium-Schicht (3) zum Metallsubstrat (1) gerichtet eine erste Grenzfläche (14) aufweist,
– Beheizen des Metallsubstrats (1) mittels einer Heizeinheit (22) auf eine Temperatur zwischen 200°C und 1000°C,
– Tempern des Bereiches der dem Metallsubstrat (1) abgewandten zweiten Grenzfläche (15) der Silizium-Schicht (3) mittels einer energieintensiven Bestrahlung während der Beheizung,
– Erzeugen von Mehrphasen im Bereich der Silizium-Schicht (3) und des Metallsubstrats (1), bestehend aus amorphem Silizium und/oder kristallinem Silizium des Siliziums der Silizium-Schicht (3) und aus kristallinem Metall des Metallsubstrats (1) und aus Silizid und
– Erzeugen von kristallinem Metall des Metallsubstrats (1).
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Patent
DE102016001949 - Offenlegung 17.08.2017; Nachanmeldungen: WO, CN, EP, US
Permalink: https://www.hzdr.de/publications/Publ-31157
P1509 - Verfahren zum Aufarbeiten von Bleiglas und Elektronikschrott
TU Bergakademie Freiberg; Wolf, R.
Abstract
Beschrieben wird ein Verfahren zum Aufarbeiten von Bleiglas und Elektronikschrott. Erfindungsgemäß umfasst dies die Schritte Zerkleinern und Vermischen des Bleiglases und des Elektronikschrottes zu einer Charge Aufschmelzen der Charge unter Zusatz einer oder mehrerer Verbindungen aus der Gruppe der Carbonate, Oxide und Hydroxide der Alkalimetalle und Reduktion des im Bleiglas enthaltenden Bleioxids durch ein Reduktionsmittel zu metallischem Blei unter Ausbildung einer Phase enthaltend eine Metallschmelze und einer Phase enthaltend eine Glasschmelze, wobei in der Glasschmelze die Konzentration von Alkalimetalloxiden im Bereich von 20 mol.-% bis 45 mol.-%
Erdalkalimetalloxiden im Bereich von 10 mol.-% bis 25 mol.-% Siliziumdioxid im Bereich von 40 mol.-% bis 50 mol.-% liegt, bezogen auf die Gesamtmenge an Alkalimetalloxiden, Erdalkalimetalloxiden und Siliziumdioxid in der Glasschmelze.
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Patent
DE102016220045 - Offenlegung: 19.04.2018
Permalink: https://www.hzdr.de/publications/Publ-31156
P1510 - Self-cleaning high temperature resistant solar selective coating
Abengoa Research S.L.; Lungwitz, F.; Neubert, M.
Abstract
Estructura selectiva solar con autolimpieza resistente a altas temperaturas. La presente invención se dirige a una estructura formada por una sección superior que comprende una capa superior que comprende TiO2 dopado que presenta una alta transmitancia en el espectro visible y una alta reflectancia en la región IR y propiedades de autolimpieza, una sección intermedia absorbente y un sustrato. Debido a las propiedades mencionadas y a la resistencia a altas temperaturas, la estructura es útil como estructura selectiva solar para receptores de torre en sistemas de energía solar por concentración (CSP).
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Patent
ES2575746 - Offenlegung 30.06.2016; Nachanmeldungen: WO, EP
Permalink: https://www.hzdr.de/publications/Publ-31155
P1506 - Complementary resistance switch,contact-connected polycrystalline piezo-or ferroelectric thin-film layer,method for encrypting a bit sequence
You, T.; Schmidt, H.; Du, N.; Bürger, D.; Skorupa, I.
Abstract
Disclosed is a complementary resistor switch (3) comprising two outer contacts, between which two piezo- or ferroelectric layers (11a and 11b) having an inner common contact are situated. At least one region (11', 11'') of the layers is modified, either the outer contacts are rectifying (S) and the inner contact is non-rectifying (0), or vice versa, the modified regions are formed at the rectifying contacts, the layers have different strain-dependent structural phases with different band gaps and/or different polarization charges, and the electrical conductivity of the layers is different. Also disclosed are a connectable resistor structure having at least one Schottky contact at two adjoining piezo- or ferroelectric layers, a polycrystalline piezo- or ferroelectric layer comprising modified crystallites, and a method and circuits for encrypting and decrypting a bit sequence.
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Patent
US20150364682 - Offenlegung 17.12.2015
Permalink: https://www.hzdr.de/publications/Publ-31154
Fusion-Based Neutron Generator Production of Tc-99m and Tc-101: A Prospective Avenue to Technetium Theranostics
Mausolf, E. J.; Johnstone, E. V.; Mayordomo, N.; Williams, D. L.; Guan, E. Y. Z.; Gary, C. K.
Abstract
Presented are the results of 99mTc and 101Tc production via neutron irradiation of natural isotopic molybdenum (Mo) with epithermal/resonance neutrons. Neutrons were produced using a deuterium-deuterium (D-D) neutron generator with an output of 2 × 1010 n/s. The separation of Tc from an irradiated source of bulk, low-specific activity (LSA) Mo on activated carbon (AC) was demonstrated. The yields of 99mTc and 101Tc, together with their potential use in medical single-photon emission computed tomography (SPECT) procedures, have been evaluated from the perspective of commercial production, with a patient dose consisting of 740 MBq (20 mCi) of 99mTc. The number of neutron generators to meet the annual 40,000,000 world-wide procedures is estimated for each imaging modality: 99mTc versus 101Tc, D-D versus deuterium-tritium (D-T) neu-tron generator system outputs, and whether or not natural molybdenum or enriched targets are used for production. The financial implications for neutron generator production of these isotopes is also presented. The use of 101Tc as a diagnostic, therapeutic, and/or theranostic isotope for use in medical applications is proposed and compared to known commercial nuclear diagnostic and therapeutic isotopes.
Keywords: Technetium-99m; molybdenum-99; neutron generator; fusion; medical isotopes; radiopharmaceuticals; diagnostic; theranostic; special nuclear material (SNM)
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Pharmaceuticals 14(2021), 875
DOI: 10.3390/ph14090875
Cited 8 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31153
New algorithm to discriminate phase distribution of gas-oil-water pipe flow with dual-modality wire-mesh sensor - Data set
de Assis Dias, F.; Nunes Dos Santos, E.; Da Silva, M. J.; Schleicher, E.; Morales, R. E. M.; Hewakandamby, B.; Hampel, U.
Abstract
Data set used on the work "New Algorithm to Discriminate Phase Distribution of Gas-Oil-Water Pipe Flow with Dual-Modality Wire-Mesh Sensor".
Data were acquired using a dual-modality wire-mesh sensor designed by the Brazilian partner UTFPR. The experiments were performed at the University of Nottingham in a water-oil liquid-liquid flow loop.
However, the gas phase was introduced into the system to perform stratified three-phase flow measurements as a proof of concept. In this set of data, you find the calibrated amplitude and phase signals of nine points as well as permittivity and conductivity estimations (post-processing).
Keywords: complex impedance; flow visualization; gas-oil-water horizontal flow; three-phase; wire-mesh sensor
Involved research facilities
- TOPFLOW Facility
Related publications
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New algorithm to discriminate phase distribution of gas-oil-water pipe flow …
ROBIS: 31145 has used this (Id 31152) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2020-06-16 Restricted access
DOI: 10.14278/rodare.372
Versions: 10.14278/rodare.373
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Permalink: https://www.hzdr.de/publications/Publ-31152
A review on numerical modelling of flashing flow with application to nuclear safety analysis
Abstract
The flashing flow is an relevant multiphase phenomenon in many technical applications including nuclear safety analysis, which has been the subject of intense research. Numerical studies have evolved from one-dimensional to multi-dimensional. A variety of methods have been proposed, while a broad consensus was not exiting. The present work aims to present an overview of available models as well their assumptions and limitations by conducting a literature survey. The final focus was put on recent computational fluid dynamics simulations. Some consensus on modelling interfacial slip, phase change mechanism and bubble size is identified. Since flashing scenarios often accompanying with high void fraction and broad bubble size range, a poly-disperse two-fluid model is recommended. Thermal phase change model is superior to pressure phase change, relaxation and equilibrium models for practical flashing problems. Major challenges include improving closure models for interphase transfer, bubble dynamics processes, interfacial area as well two-phase turbulence. For this purpose, high-resolution high quality experimental data are important, which are lacking in many cases. Considering that heterogeneous gas structures often exist in flashing flows, multi-field approaches able to handle different shapes of gas-liquid interface are recommended.
Keywords: computational fluid dynamics; flashing flow; nuclear safety analysis; numerical modelling; literature review
Involved research facilities
- TOPFLOW Facility
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Applied Thermal Engineering 182(2021), 116002
Online First (2020) DOI: 10.1016/j.applthermaleng.2020.116002
Cited 36 times in Scopus
Downloads
- Final Draft PDF 1,3 MB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-31151
Reconciling Ionization Energies and Band Gaps of Warm Dense Matter \\Derived with {\it Ab Initio} Simulations and Average Atom Models
Massacrier, G.; Böhme, M.; Vorberger, J.; Soubiran, F.; Militzer, B.
Abstract
Average atom (AA) models allow one to efficiently compute electronic and optical properties of materials over a wide range of conditions and are thus often employed to interpret experimental data. However, at high pressure, predictions from AA models have been shown to disagree with results from many-body {\it ab initio} computer simulations. Here we reconcile these deviations by developing an innovative type of AA model, \Avion, that computes the electronic eigenstates with novel boundary conditions within the ion sphere. Bound and free states are thus derived consistently. We drop the common AA assumption that the free-particle spectrum starts at the potential threshold, which we found to be incompatible with {\it ab initio} calculations. We perform {\it ab initio} simulations of crystalline and liquid carbon and aluminum over a wide range of densities and show that the computed band structure is in very good agreement with predictions from \Avion.
Keywords: Warm Dense Matter; Ab initio; density functional theory; molecular dynamics; average atom; High Energy Density; ionization potential depression
Related publications
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DFT/DFT-MD IPD Publication Data
ROBIS: 32435 HZDR-primary research data are used by this (Id 31149) publication
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Physical Review Research 3(2021), 023026
DOI: 10.1103/PhysRevResearch.3.023026
Cited 13 times in Scopus -
Lecture (Conference)
(Online presentation)
APS March Meeting 2021, 15.-19.03.2021, Washington DC, USA
Permalink: https://www.hzdr.de/publications/Publ-31149
Modelling and Simulation of Flow Boiling with an Eulerian-Eulerian Approach and Integrated Models for Bubble Dynamics and Temperature-dependent Heat Partitioning
Setoodeh, H.; Ding, W.; Lucas, D.; Hampel, U.
Abstract
A time-averaged Eulerian-Eulerian (E-E) multiphase approach for the simulation of boiling flows is presented. A previously developed bubble dynamics model is implemented in the E-E framework as a sub-model to improve the accuracy of the simulations and reduce the case dependency. This mechanistic model, which is based on the balance of forces applied on a single bubble, considers the evaporation of the microlayer underneath the bubble, thermal diffusion and condensation around the bubble cap as well as geometry changes and dynamic inclination and contact angles. The advantage of this model is that it does not require a recalibration of parameters to predict the bubble departure size. However, its implementation in the E-E framework needs an extension of the current nucleation site activation and heat partitioning model. Further on, we use a population balance model in our approach.
With the new modelling approach, we are able to analyse the impact of bubble sliding on the heat transfer, which has been rarely considered in other modelling approaches. Validation was made with experimental data from flow in a vertical pipe and an annulus. The experimental test cases cover a wide range of operating parameters such as wall heat flux, fluid velocity, subcooling temperature and pressure.
Keywords: bubble dynamics; heat partitioning; subcooled flow boiling; Computational Fluid Dynamics (CFD)
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International Journal of Thermal Sciences 161(2021), 106709
Online First (2020) DOI: 10.1016/j.ijthermalsci.2020.106709
Cited 22 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31148
Stone-Wales defects cause high proton permeability and isotope selectivity of single-layer graphene
An, Y.; Faria Oliveira, A.; Brumme, T.; Kuc, A. B.; Heine, T.
Abstract
While the isotope-dependent hydrogen permeability of graphene membranes at ambient condition has been demonstrated, the underlying mechanism has been controversially discussed during the past five years. The reported room temperature H+-over-D+ selectivity is 10, much higher than in any competing method. Yet, it has not been understood how protons can penetrate through graphene membranes – proposed hypotheses include atomic defects and local hydrogenation. However, neither could explain both the high permeability and high selectivity of the atomically thin membranes. Here, we confirm that ideal graphene is quasi-impermeable to protons, yet the most common defect in sp2 carbons, the topological Stone-Wales defect, has a calculated penetration barrier below 1 eV and H+-over-D+ selectivity of 7 at room temperature and, thus, explains all experimental results on graphene membrane that are available to date. We challenge the competing explanation, local hydrogenation, which also reduces the penetration barrier, but shows significantly lower isotope selectivity
Keywords: proton isotopes separation; quantum tunneling; graphene; Stone-Wales defect; selectivity
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Advanced Materials 32(2020)37, 2002442
DOI: 10.1002/adma.202002442
Cited 35 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31147
In situ X-ray diffraction of silicate liquids and glasses under dynamic and static compression to megabar pressures
Morard, G.; Hernandez, J.-A.; Guarguaglini, M.; Bolis, R.; Benuzzi-Mounaix, A.; Vinci, T.; Fiquet, G.; Baron, M. A.; Heon Shim, S.; Ko, B.; Gleason, A. E.; Mao, W. L.; Alonso-Mori, R.; Ja Lee, H.; Nagler, B.; Galtier, E.; Sokaras, D.; Glenzer, S. H.; Andrault, D.; Garbarino, G.; Mezouar, M.; Schuster, A.; Ravasio, A.
Abstract
Properties of liquid silicates under high-pressure and high- temperature conditions are critical for modeling the dynamics and solidification mechanisms of the magma ocean in the early Earth, as well as for constraining entrainment of melts in the mantle and in the present-day core–mantle boundary. Here we present in situ structural measurements by X-ray diffraction of selected amorphous silicates compressed statically in diamond anvil cells (up to 157 GPa at room temperature) or dynamically by laser-generated shock com- pression (up to 130 GPa and 6,000 K along the MgSiO3 glass Hugo- niot). The X-ray diffraction patterns of silicate glasses and liquids reveal similar characteristics over a wide pressure and temperature range. Beyond the increase in Si coordination observed at 20 GPa, we find no evidence for major structural changes occurring in the silicate melts studied up to pressures and temperatures exceeding Earth’s core mantle boundary conditions. This result is supported by molecular dynamics calculations. Our findings reinforce the widely used assumption that the silicate glasses studies are appropriate structural analogs for understanding the atomic arrangement of silicate liquids at these high pressures.
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Proceedings of the National Academy of Sciences of the United States of America 117(2020)22, 11981-11986
DOI: 10.1073/pnas.1920470117
Cited 24 times in Scopus
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Permalink: https://www.hzdr.de/publications/Publ-31146
New algorithm to discriminate phase distribution of gas-oil-water pipe flow with dual-modality wire-mesh sensor
de Assis Dias, F.; Nunes Dos Santos, E.; Da Silva, M. J.; Schleicher, E.; Morales, R. E. M.; Hewakandamby, B.; Hampel, U.
Abstract
Three-phase gas-oil-water flow is an important type of flow present in petroleum extraction and processing. This paper reports a novel threshold-based method to visualize and estimate the cross-sectional phase fraction of gas-oil-water mixtures. A 16x16 dual-modality wire-mesh sensor (WMS) was employed to simultaneously determine the conductive and capacitive components of the impedance of fluid. Then, both electrical parameters are used to classify readings of WMS into either pure substance (gas, oil or water) or two-phase oil-water mixtures (foam is neglected in this work). Since the wire-mesh sensor interrogates small regions of the flow domain, we assume that the three-phase mixture can be segmented according to the spatial sensor resolution (typically 2-3 mm). Hence, the proposed method simplifies a complex three-phase system in several segments of single or two-phase mixtures. In addition to flow visualization, the novel approach can also be applied to estimate quantitative volume fractions of flowing gas-oil-water mixtures. The proposed method was tested in a horizontal air-oil-water flow loop in different flow conditions. Experimental results suggest that the threshold-based method is able to capture transient three-phase flows with high temporal and spatial resolution even in the presence of water-oil dispersion regardless of the continuous phase.
Keywords: complex impedance; flow visualization; gas-oil-water horizontal flow; three-phase; wire-mesh sensor
Related publications
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New algorithm to discriminate phase distribution of gas-oil-water pipe flow …
ROBIS: 31152 HZDR-primary research data are used by this (Id 31145) publication
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IEEE Access 8(2020), 125163-125178
DOI: 10.1109/ACCESS.2020.3007678
Cited 15 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31145
The anomalous magnetic moment of the muon in the Standard Model
Aoyama, T.; Asmussen, N.; Benayoun, M.; Bijnens, J.; Blum, T.; Bruno, M.; Caprini, I.; Carloni Calame, C. M.; Cè, M.; Colangelo, G.; Curciarello, F.; Czyż, H.; Danilkin, I.; Davier, M.; Davies, C. T. H.; Della Morte, M.; Eidelman, S. I.; El-Khadra, A. X.; Gérardin, A.; Giusti, D.; Golterman, M.; Steven, G.; Gülpers, V.; Hagelstein, F.; Hayakawa, M.; Herdoíza, G.; Hertzog, D. W.; Hoecker, A.; Hoferichter, M.; Hoid, B.-L.; Hudspith, R. J.; Ignatov, F.; Izubuchi, T.; Jegerlehner, F.; Jin, L.; Keshavarzi, A.; Kinoshita, T.; Kubis, B.; Kupich, A.; Kupść, A.; Laub, L.; Lehner, C.; Lellouch, L.; Logashenko, I.; Malaescu, B.; Maltman, K.; Marinković, M. K.; Masjuan, P.; Meyer, A. S.; Meyer, H. B.; Mibe, T.; Miura, K.; Müller, S.; Nio, M.; Nomura, D.; Nyffeler, A.; Pascalutsa, V.; Passera, M.; Perez Del Rio, E.; Peris, S.; Portelli, A.; Procura, M.; Redmer, C. F.; Roberts, B. L.; Sánchez-Puertas, P.; Serednyakov, S.; Shwartz, B.; Simula, S.; Stöckinger, D.; Stöckinger-Kim, H.; Stoffer, P.; Teubner, T.; van de Water, R.; Vanderhaeghen, M.; Venanzoni, G.; von Hippel, G.; Wittig, H.; Zhang, Z.; Achasov, M. N.; Bashir, A.; Cardoso, N.; Chakraborty, B.; Chao, E.-H.; Charles, J.; Crivellin, A.; Deineka, O.; Denig, A.; Detar, C.; Dominguez, C. A.; Dorokhov, A. E.; Druzhinin, V. P.; Eichmann, G.; Fael, M.; Fischer, C. S.; Gámiz, E.; Gelzer, Z.; Green, J. R.; Guellati-Khelifa, S.; Hatton, D.; Hermansson-Truedsson, N.; Holz, S.; Hörz, B.; Knecht, M.; Koponen, J.; Kronfeld, A. S.; Laiho, J.; Leupold, S.; Mackenzie, P. B.; Marciano, W. J.; Mcneile, C.; Mohler, D.; Monnard, J.; Neil, E. T.; Nesterenko, A. V.; Ottnad, K.; Pauk, V.; Radzhabov, A. E.; de Rafael, E.; Raya, K.; Risch, A.; Rodríguez-Sánchez, A.; Roig, P.; San José, T.; Solodov, E. P.; Sugar, R.; Todyshev, K. Y.; Vainshtein, A.; Vaquero Avilés-Casco, A.; Weil, E.; Wilhelm, J.; Williams, R.; Zhevlakov, A. S.
Abstract
We review the present status of the Standard Model calculation of the anomalous magnetic moment of the muon. This is performed in a perturbative expansion in the fine-structure constant α and is broken down into pure QED, electroweak, and hadronic contributions. The pure QED contribution is by far the largest and has been evaluated up to and including O(α5) with negligible numerical uncertainty. The electroweak contribution is suppressed by (m_μ/M_W)^2 and only shows up at the level of the seventh significant digit. It has been evaluated up to two loops and is known to better than one percent. Hadronic contributions are the most difficult to calculate and are responsible for almost all of the theoretical uncertainty. The leading hadronic contribution appears at O(α2) and is due to hadronic vacuum polarization, whereas at O(α3) the hadronic light-by-light scattering contribution appears. Given the low characteristic scale of this observable, these contributions have to be calculated with nonperturbative methods, in particular, dispersion relations and the lattice approach to QCD. The largest part of this review is dedicated to a detailed account of recent efforts to improve the calculation of these two contributions with either a data-driven, dispersive approach, or a first-principle, lattice-QCD approach. The final result reads a^{SM}_μ=116591810(43)×10^{−11} and is smaller than the Brookhaven measurement by 3.7σ. The experimental uncertainty will soon be reduced by up to a factor four by the new experiment currently running at Fermilab, and also by the future J-PARC experiment. This and the prospects to further reduce the theoretical uncertainty in the near future-which are also discussed here-make this quantity one of the most promising places to look for evidence of new physics.
Keywords: muon; g-2; anomalous magnetic moment
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Physics Reports 887(2020), 1-166
DOI: 10.1016/j.physrep.2020.07.006
Cited 954 times in Scopus -
Contribution to WWW
arXiv:2006.04822v1 [hep-ph]: https://arxiv.org/abs/2006.04822
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Permalink: https://www.hzdr.de/publications/Publ-31144
Towards Geostatistical Learning for the Geosciences: A Case Study in Improving the Spatial Awareness of Spectral Clustering
Talebi, H.; Peeters, L. J. M.; Mueller, U.; Tolosana Delgado, R.; van den Boogaart, K. G.
Abstract
The particularities of geosystems and geoscience data must be understood before any development or implementation of statistical learning algorithms. Without such knowledge, the predictions and inferences may not be accurate and physically consistent. Accuracy, transparency and interpretability, credibility, and physical realism are minimum criteria for statistical learning algorithms when applied to the geosciences. This study briefly reviews several characteristics of geoscience data and challenges for novel statistical learning algorithms. A novel spatial spectral clustering approach is introduced to illustrate how statistical learners can be adapted for modelling geoscience data. The spatial awareness and physical realism of the spectral clustering are improved by utilising a dissimilarity matrix based on nonparametric higher-order spatial statistics. The proposed model-free technique can identify meaningful spatial clusters (i.e. meaningful geographical subregions) from multivariate spatial data at different scales without the need to define a model of co-dependence. Several mixed (e.g. continuous and categorical) variables can be used as inputs to the proposed clustering technique. The proposed technique is illustrated using synthetic and real mining datasets. The results of the case studies confirm the usefulness of the proposed method for modelling spatial data.
Keywords: Statistical learning; Spatial data; Spatial clustering; Higher-order spatial statistics; Geoscience data
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Mathematical Geosciences 52(2020), 1035-1048
DOI: 10.1007/s11004-020-09867-0
Cited 12 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31143
Combined tumor plus nontumor interim FDG‐PET parameters are prognostic for response to chemoradiation in squamous cell esophageal cancer
Zschaeck, S.; Li, Y.; Bütof, R.; Lili, C.; Hua, W.; Troost, E.; Beck, M.; Amthauer, H.; Kaul, D.; Kotzerke, J.; Baur, A.; Ghadjar, P.; Baumann, M.; Krause, M.; Hofheinz, F.
Abstract
We have investigated the prognostic value of two novel interim 18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) parameters in patients undergoing chemoradiation (CRT) for esophageal squamous cell carcinoma (ESCC): one tumor parameter (maximal standardized uptake ratio rSUR) and one normal tissue parameter (change of FDG uptake within irradiated nontumor‐affected esophagus ∆ SUVNTO). PET data of 134 European and Chinese patients were analyzed. Parameter establishment was based on 36 patients undergoing preoperative CRT plus surgery, validation was performed in 98 patients receiving definitive CRT. Patients received PET imaging prior and during fourth week of CRT. Clinical parameters, baseline PET parameters, and interim PET parameters (rSUR and ∆ SUVNTO) were analyzed and compared to event‐free survival (EFS), overall survival (OS), loco‐regional control (LRC) and freedom from distant metastases (FFDM). Combining rSUR and ∆ SUVNTO revealed a strong prognostic impact on EFS, OS, LRC and FFDM in patients undergoing preoperative CRT. In the definitive CRT cohort, univariate analysis with respect to EFS revealed several staging plus both previously established interim PET parameters as significant prognostic factors. Multivariate analyses revealed only rSUR and ∆ SUVNTO as independent prognostic factors (p = 0.003, p = 0.008). Combination of these parameters with the cutoff established in preoperative CRT revealed excellent discrimination of patients with a long or short EFS (73% vs . 17% at 2 years, respectively) and significantly discriminated all other endpoints (OS, p < 0.001; LRC, p < 0.001; FFDM, p = 0.02), even in subgroups. Combined use of interim FDG‐PET derived parameters ∆ SUVNTO and rSUR seems to have predictive potential, allowing to select responders for definitive CRT and omission of surgery.
Keywords: esophageal cancer; interim PET; standardized uptake ratio; normal tissue FDG uptake; chemoradiation; personalized treatment
Involved research facilities
- PET-Center
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International Journal of Cancer 147(2020)5, 1427-1436
DOI: 10.1002/ijc.32897
Cited 6 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31142
Reconstructed spatial resolution and contrast recovery with Bayesian penalized likelihood reconstruction (Q.Clear) for FDG-PET compared to time-of-flight (TOF) with point spread function (PSF)
Rogasch, J.; Suleiman, S.; Hofheinz, F.; Bluemel, S.; Lukas, M.; Amthauer, H.; Furth, C.
Abstract
Background
Bayesian penalized likelihood reconstruction for PET (e.g., GE Q.Clear) aims at improving convergence of lesion activity while ensuring sufficient signal-to-noise ratio (SNR). This study evaluated reconstructed spatial resolution, maximum/peak contrast recovery (CRmax/CRpeak) and SNR of Q.Clear compared to time-of-flight (TOF) OSEM with and without point spread function (PSF) modeling.
Methods
The NEMA IEC Body phantom was scanned five times (3 min scan duration, 30 min between scans, background, 1.5–3.9 kBq/ml F18) with a GE Discovery MI PET/CT (3-ring detector) with spheres filled with 8-, 4-, or 2-fold the background activity concentration (SBR 8:1, 4:1, 2:1). Reconstruction included Q.Clear (beta, 150/300/450), “PSF+TOF4/16” (iterations, 4; subsets, 16; in-plane filter, 2.0 mm), “OSEM+TOF4/16” (identical parameters), “PSF+TOF2/17” (2 it, 17 ss, 2.0 mm filter), “OSEM+TOF2/17” (identical), “PSF+TOF4/8” (4 it, 8 ss, 6.4 mm), and “OSEM+TOF2/8” (2 it, 8 ss, 6.4 mm). Spatial resolution was derived from 3D sphere activity profiles. RC as (sphere activity concentration [AC]/true AC). SNR as (background mean AC/background AC standard deviation).
Results
Spatial resolution of Q.Clear150 was significantly better than all conventional algorithms at SBR 8:1 and 4:1 (Wilcoxon, each p < 0.05). At SBR 4:1 and 2:1, the spatial resolution of Q.Clear300/450 was similar or inferior to PSF+TOF4/16 and OSEM+TOF4/16. Small sphere CRpeak generally underestimated true AC, and it was similar for Q.Clear150/300/450 as with PSF+TOF4/16 or PSF+TOF2/17 (i.e., relative differences < 10%). Q.Clear provided similar or higher CRpeak as OSEM+TOF4/16 and OSEM+TOF2/17 resulting in a consistently better tradeoff between CRpeak and SNR with Q.Clear. Compared to PSF+TOF4/8/OSEM+TOF2/8, Q.Clear150/300/450 showed lower SNR but higher CRpeak.
Conclusions
Q.Clear consistently improved reconstructed spatial resolution at high and medium SBR compared to PSF+TOF and OSEM+TOF, but only with beta = 150. However, this is at the cost of inferior SNR with Q.Clear150 compared to Q.Clear300/450 and PSF+TOF4/16/PSF+TOF2/17 while CRpeak for the small spheres did not improve considerably. This suggests that Q.Clear300/450 may be advantageous for the 3-ring detector configuration because the tradeoff between CR and SNR with Q.Clear300/450 was superior to PSF+TOF4/16, OSEM+TOF4/16, and OSEM+TOF2/17. However, it requires validation by systematic evaluation in patients at different activity and acquisition protocols.
Keywords: PET; Image reconstruction; Spatial resolution; Contrast recovery; Signal-to-noise ratio; TOF; PSF; Q.Clear; GE Discovery MI
Involved research facilities
- PET-Center
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EJNMMI Physics 7(2020), 2
DOI: 10.1186/s40658-020-0270-y
Cited 37 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31141
Start-to-end simulations Modeling hybrid plasma accelerator experiments with PIConGPU
Pausch, R.; Bachmann, M.; Garten, M.; Hübl, A.; Steiniger, K.; Widera, R.; Kurz, T.; Schöbel, S.; Chang, Y.-Y.; Couperus Cabadağ, J. P.; Köhler, A.; Zarini, O.; Heinemann, T.; Ding, H.; Döpp, A.; Gilljohann, M. F.; Kononenko, O.; Raj, G.; Corde, S.; Hidding, B.; Karsch, S.; Assmann, R.; Martinez De La Ossa, A.; Irman, A.; Schramm, U.; Debus, A.
Abstract
A brief summary of the evolution of LPWFA hybrid simulations and why start-to end simulations are needed to model the LPWFA setup.
Keywords: LPWFA; hybrid; PIConGPU
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Lecture (Conference)
(Online presentation)
DMA meeting, 20.05.2020, Dresden, Deutschland
Permalink: https://www.hzdr.de/publications/Publ-31140
Electric and magnetic dipole strength in 66Zn
Schwengner, R.; Massarczyk, R.; Scheck, M.; Tornow, W.; Brown, B. A.; Battaglia, G.; Beck, T.; Bemmerer, D.; Benouaret, N.; Beyer, R.; Butterling, M.; Fiedler, F.; Finch, S. W.; Fransen, C.; Friman-Gayer, U.; Frotscher, A.; Gonzalez, R.; Grieger, M.; Hartmann, A.; Hensel, T.; Hoemann, E.; Hoffmann, H.; Isaak, J.; Janssens, R. V. F.; Johnson, S.; Jones, M. D.; Junghans, A.; Kelly, N.; Kleemann, J.; Krishichayan, F.; Little, D. R.; Ludwig, F.; Müller, S.; Odonnell, D.; Pirovano, E.; Savran, D.; Sinclair, J.; Takacs, M. P.; Turkat, S.; Urlaß, S.; Wagner, A.; Wieland, O.; Wilhelmy, J.
Abstract
The dipole strength of the nuclide 66Zn was studied in photon-scattering experiments using bremsstrahlung produced with electron beams of energies of 7.5 and 13.4 MeV at the γELBE facility as well as using quasi-monoenergetic and linearly polarized photon beams of 30 energies within the range from 4.3 to 9.9 MeV at the HIγS facility. About 140 J = 1 states were identified, out of them 9 with 1+ and 84 with 1- assignments. The quasicontinuum of unresolved transitions was included in the analysis of the spectra and the intensities of branching transitions were estimated on the basis of simulations of statistical γ-ray cascades. As a result, the photoabsorpton cross section up to the neutron-separation energy was determined and compared with predictions of the statistical reaction model. The experimental M1 strengths from resolved 1+ states are compared with results of large-scale shell-model calculations.
Keywords: Photon scattering; nuclear resonance fluorescence; dipole excitations; photoabsorption cross section; electromagnetic transitions; statistical reaction model; shell model
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- γ-ELBE DOI: 10.58065/24020
Related publications
- DOI: 10.58065/24020 is cited by this (Id 31139) publication
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31139) publication
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Physical Review C 103(2021), 024312
DOI: 10.1103/PhysRevC.103.024312
Cited 5 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31139
Nonlocal stimulation of three-magnon splitting in a magnetic vortex
Körber, L.; Schultheiß, K.; Hula, T.; Verba, R.; Faßbender, J.; Kakay, A.; Schultheiß, H.
Abstract
We present a combined numerical, theoretical and experimental study on stimulated three-magnon splitting in a magnetic disk in the vortex equilibrium state. Our micromagnetic simulations and Brillouin-light-scattering results confirm that three-magnon splitting can be triggered even below threshold by exciting one of the secondary modes by magnons propagating in a waveguide next to the disk. The experiments show that stimulation is possible over an extended range of excitation powers and a wide range of frequencies around the eigenfrequencies of the secondary modes. Rate-equation calculations predict an instantaneous response to stimulation and the possibility to prematurely trigger three-magnon splitting even above threshold in a sustainable manner. These predictions are confirmed experimentally using time-resolved Brillouin-light-scattering measurements and are in a good qualitative agreement with the theoretical results. We believe that the controllable mechanism of stimulated three-magnon splitting could provide a possibility to utilize magnon-based nonlinear networks as hardware for reservoir or neuromorphic computing.
Here, we briefly describe how the archived data for the publication "Nonlocal stimulation of three-magnon splitting in a magnetic vortex", submitted to PRL, is structured.
"rate-equations"
- theoretical data of the temporal evolution of the spin wave modes in Fig. 4
"micromagnetic-simulation"
- MuMax3 simulation recipes (.go files) and sample-layout masks for the
simulations performed for Fig. 2(a,b,c).
- corresponding power spectra obtained with our "mumax3-pwsp" program
- mode profiles for stimulated and spontaneous splitting (Fig. 1(c) and Fig. 2(d))
- dispersion of the spin waves, calculated by micromagetnic simulation, shown in Fig. 1(b)
"experiments"
- electron beam microscopy image of the sample
- intensity spectrum of the waveguide, used to calculate the approximate
frequency/wave-vector region where the waveguide is effective (inset in Fig. 1(c))
- non-time-resolved BLS measurements, including spectra, power sweeps, etc. for
Figs 2,3 in "i3MS" folders, in more detail described by "i3MS_V1_KS_logbook.pdf"
- time-resolved BLS measurements, further explained in the corresponding subfolders
Keywords: spin wave; nonlinear; three-magnon splitting; stimulation; micromagnetic simulation; BLS
Related publications
- DOI: 10.1103/PhysRevLett.125.207203 references this (Id 31137) publication
- ARXIV: 2005.12663 has this (Id 31137) publication as part
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Nonlocal stimulation of three-magnon splitting in a magnetic vortex
ROBIS: 31058 has used this (Id 31137) publication of HZDR-primary research data
-
Reseach data in the HZDR data repository RODARE
Publication date: 2020-06-11 Open access
DOI: 10.14278/rodare.364
Versions: 10.14278/rodare.365
License: CC-BY-4.0
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Permalink: https://www.hzdr.de/publications/Publ-31137
Treatment of brain metastases in small cell lung cancer: Decision-making amongst a multidisciplinary panel of European experts
Putora, P. M.; Fischer, G. F.; Früh, M.; Califano, R.; Faivre-Finn, C.; van Houtte, P.; Mcdonald, F.; Nestle, U.; Dziadziuszko, R.; Le Pechoux, C.; Ramella, S.; Belderbos, J.; Slotman, B. J.; Troost, E. G. C.; Peeters, S.; Widder, J.; Pöttgen, C.; Reck, M.; Blackhall, F.; Cappuzzo, F.; Besse, B.; Novello, S.; Garrido, P.; Felip, E.; O'Brien, M.; Paz Ares, L.; de Marinis, F.; Westeel, V.; de Ruysscher, D.
Abstract
Background: Brain metastases (BM) are common in patients with small cell lung cancer (SCLC). In recent years, the role of whole brain radiotherapy (WBRT) for brain metastases in lung cancer is being reevaluated, especially in the context of new systemic treatments available for SCLC. With this analysis, we investigate decision-making in SCLC patients with BM among European experts in medical oncology and radiation oncology. Methods: We analyzed decision-making from 13 medical oncologists (selected by IASLC) and 13 radiation oncologists (selected by ESTRO) specialized in SCLC. Management strategies of individual experts were converted into decision trees and analyzed for consensus. Results and conclusion: In asymptomatic patients, chemotherapy alone is the most commonly recommended first line treatment. In asymptomatic patients with limited volume of brain metastases, a higher preference for chemotherapy without WBRT among medical oncologists compared to radiation oncologists was observed. For symptomatic patients, WBRT followed by chemotherapy was recommended most commonly. For limited extent of BM in symptomatic patients, some experts chose stereotactic radiotherapy as an alternative to WBRT. Significant variation in clinical decision-making was observed among European SCLC experts for the first line treatment of patients with SCLC and BM.
Keywords: Brain metastases; Chemotherapy; Decision-making; Small cell lung cancer; Stereotactic radiotherapy; Whole brain radiotherapy
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Radiotherapy and Oncology 149(2020), 84-88
DOI: 10.1016/j.radonc.2020.04.015
Cited 15 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31136
Local void fraction and pressure drop data for horizontal annular flow through orifice
Porombka, P.; Boden, S.; Lucas, D.; Hampel, U.
Abstract
This dataset combines multiple measurements form air-water horizontal annular flow experiments in a pipe (case A) and a pipe with circular orifice with \(d^2 / D^2 = 0.6\) (case B). Measurements where taken at superficial Reynolds numbers of Re=25000 for the gas phase and Re =4090 for the liquid phase. The following data are included for each case:
- linear pressure drop between two points (case A), four points (case B) measured with split-range differential pressure transducers at 5Hz
- time-averaged local liquid volume fraction distribution in cylindrical and Cartesian coordinates reconstructed from X-ray microtomography projections
- reconstructed pipe axis coordinates and pipe radius
- Python code to calculate secondary validation parameters (e.g. film thickness distribution) from primary data
The detailed 3D data is intended for validation of computational fluid dynamics codes based on phase-averaged variables such as the Euler-Euler approach.
Keywords: X-ray microtomography; film thickness; circular orifice; annular flow
Related publications
- DOI: 10.1007/s00348-020-03091-6 references this (Id 31135) publication
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Horizontal annular flow through orifice studied by X-ray microtomography
ROBIS: 30820 has used this (Id 31135) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2020-06-09 Restricted access
DOI: 10.14278/rodare.361
Versions: 10.14278/rodare.363 | 362
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Permalink: https://www.hzdr.de/publications/Publ-31135
Hydrodynamic forces on a clean spherical bubble translating in a wall-bounded linear shear flow
Shi, P.; Rzehak, R.; Lucas, D.; Magnaudet, J.
Abstract
The three-dimensional flow around a spherical clean bubble translating steadily in a wall-bounded linear shear flow is studied numerically. The present work is concerned with the drag and lift forces experienced by the bubble over a wide range of Reynolds number (0.1 ≤ Re ≤ 10^3, Re being based on the bubble diameter and relative velocity with respect to the ambient fluid), wall distance (1.5 ≤ LR ≤ 8, LR being the distance from the bubble center to the wall normalized by the bubble radius), and relative shear rate -0.5 ≤ Sr ≤ 0.5, Sr being the ratio between the velocity difference across the bubble and the relative velocity).Based on the above range of parameters, situations where the bubble is repelled from or attracted to the wall are both covered. The flow structure and vorticity field are analyzed to obtain qualitative insight into the interaction mechanisms at work. The drag and lift forces are computed as well. Their variations agree well with theoretical predictions available in the limit of low-but-finite Reynolds number and, when the fluid is at rest, in the potential flow limit. Numerical results and analytical expressions are combined to provide accurate semi-empirical expressions for the drag and lift forces at arbitrary Reynolds number and separation distance.
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Physical Review Fluids 5(2020), 073601
DOI: 10.1103/PhysRevFluids.5.073601
Cited 19 times in Scopus
Downloads
- Final Draft PDF 7,9 MB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-31134
Olfactory dysfunction correlates with putaminal dopamine turnover in early de novo Parkinson’s disease
Löhle, M.; Wolz, M.; Beuthien-Baumann, B.; Oehme, L.; van den Hoff, J.; Kotzerke, J.; Reichmann, H.; Storch, A.
Abstract
Although olfactory dysfunction is one of the most well-established prodromal symptoms in Parkinson’s disease (PD), its correlation with clinical disease progression or dopaminergic dysfunction still remains unclear. We here evaluated the association of striatal dopamine metabolism and olfactory function in a homogenous cohort of 30 patients with early untreated de novo PD. Striatal dopamine metabolism was assessed by the extended 18Fluorodopa PET scanning protocol to measure 18Fluorodopa uptake (Kocc) and the effective dopamine distribution volume ratio (EDVR) as the inverse of dopamine turnover. Olfactory function was estimated by the “Sniffin’ Sticks” test including odor threshold (T), discrimination (D) and identification (I) assessment. We detected moderate correlations of the EDVR in the posterior putamen with the TDI composite score (r = 0.412; p = 0.024; Pearson’s correlation test) and the odor identification score (r = 0.444; p = 0.014). These correlations were confirmed by multivariate regression analyses using age, sex, symptom duration and disease severity as measured by UPDRSIII motor score as candidate covariates. No other associations were observed between olfaction measures and Kocc and EDVR in all striatal regions. Together, olfactory dysfunction in early PD is not correlated with striatal 18Fluorodopa uptake as a measure for dopaminergic degeneration, but with putaminal dopamine turnover as a marker for dopaminergic presynaptic compensatory processes in early PD. These results should be treated as hypothesis generating and require confirmation by larger multicenter studies.
Involved research facilities
- PET-Center
-
Journal of Neural Transmission 127(2020), 9-16
DOI: 10.1007/s00702-019-02122-9
Cited 7 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31133
Predicting the dominating factors during heat transfer in magnetocaloric composite wires
Krautz, M.; Beyer, L.; Funk, A.; Waske, A.; Weise, B.; Freudenberger, J.; Gottschall, T.
Abstract
Magnetocaloric composite wires have been studied by pulsed-field measurements up to μ0ΔH = 10 T with a typical rise time of 13 ms in order to evaluate the evolution of the adiabatic temperature change of the core, ΔTad, and to determine the effective temperature change at the surrounding steel jacket, ΔTeff, during the field pulse. An inverse thermal hysteresis is observed for ΔTad due to the delayed thermal transfer. By numerical simulations of application-relevant sinusoidal magnetic field profiles, it can be stated that for field-frequencies of up to two field cycles per second heat can be efficiently transferred from the core to the outside of the jacket. In addition, intense numerical simulations of the temperature change of the core and jacket were performed by varying different parameters, such as frequency, heat capacity, thermal conductivity and interface resistance in order to shed light on their impact on ΔTeff at the outside of the jacket in comparison to ΔTad provided by the core.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
-
Materials and Design 193(2020), 108832
DOI: 10.1016/j.matdes.2020.108832
Cited 7 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31131
The influence of different artificial extracellular matrix implant coatings on the regeneration of a critical size femur defect in rats
Förster, Y.; Schulze, S.; Penk, A.; Neuber, C.; Möller, S.; Hintze, V.; Scharnweber, D.; Schnabelrauch, M.; Pietzsch, J.; Huster, D.; Rammelt, S.
Abstract
Resorbable biomaterials based on artificial extracellular matrices (aECM) represent promising scaffolds for the treatment of large bone defects. Here, we investigated various glycosaminoglycan (GAG) derivatives of varying sulfation degree with respect to their influence on in vivo bone healing. The materials used in this study consisted of GAG-coated degradable polycaprolactone-co-lactide (PCL). Critical size femur defects in rats were filled with autologous bone serving as positive control or the respective coated or uncoated PCL scaffolds. After 2 and 12 weeks, progress in the healing process was investigated by analyzing the new bone matrix formation, the collagen content and hydroxyapatite formation by using micro-computed tomography (μCT), biomechanical testing, nuclear magnetic resonance spectroscopy (NMR) and histology. The sulfated GAG coating contributed substantially to bone regeneration, increased collagen synthesis and initiated mineralization of the organic matrix. Most substantial collagen production was detected in scaffolds coated with chondroitin sulfate. Scaffolds coated with hypersulfated hyaluronan induced formation of new bone volume comparable to what was observed in the positive control. GAG differing in the sugar backbone and degree of sulfation modulate the healing process at different times, eventually leading to improved bone healing.
Keywords: Artificial extracellular matrices; Glycosaminoglycans; Chondroitin sulfate; Sulfated hyaluronan; Bone healing
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Materials Science and Engineering C 116(2020), 111157
DOI: 10.1016/j.msec.2020.111157
Cited 9 times in Scopus
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- Secondary publication expected
Permalink: https://www.hzdr.de/publications/Publ-31130
Software for: Characterization of blood coagulation dynamics and oxygenation in ex-vivo retinal vessels by fluorescence hyperspectral imaging
Abstract
The Mathematica software for the analysis of blood oxygenation in the intact or damaged retinal vessel from the fluorescence hyperspectral data using optimized two-component empirical asymmetric log-normal lineshape (LN) spectral model (Urbancic et al, Opt. Express 21, 2013) modified with hemoglobin absorbance correction.
Related publications
- DOI: 10.1002/jbio.202000021 references this (Id 31129) publication
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Characterization of blood coagulation dynamics and oxygenation in ex‐vivo …
ROBIS: 30922 has used this (Id 31129) publication of HZDR-primary research data
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Software in the HZDR data repository RODARE
Publication date: 2020-06-03 Open access
DOI: 10.14278/rodare.359
Versions: 10.14278/rodare.360
License: CC-BY-4.0
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Permalink: https://www.hzdr.de/publications/Publ-31129
Compositional modelling of the impact of source lithology on the plant ionome
Pospiech, S.; van den Boogaart, K. G.; Tolosana Delgado, R.; Middleton, M.
Abstract
The plant ionome is used for many applications for which it is important to understand and model how the elemental composition in the plants or plant organs evolved based on the available element sources, e.g. the effect of the soils or the underlying lithologies. Since the uptake and translocation of elements is influenced by a multitude of non-controllable parameters it is very challenging to relate a certain element pattern specifically to one parameter and quantify the effect of the parameter. Additionally, the applied modelling tools often do not take into account that both, the plant ionome and the element source, are multi-element concentrations. Concentrations are compositional data which represent the relative importance of some parts of a whole, and thus they are constrained and typically might suffer from problems of spurious correlations and negative bias, which disturbs our models of plant uptake.
In this contribution, we are presenting a statistical approach to describe the relation between geochemical composition of plants and the bedrock lithology while taking the multi-variate and constrained nature of concentrations into account. Modern compositional data analysis relies on log-ratio transforms and the Aitchison geometry. Most of the processes building the plant ionome from the element sources can be understood as linear modifications in the log-ratio space. A selective element transport would correspond to a shift of log-ratios. If this selectivity varies randomly this shift can be modelled by a multivariate normal distribution in log-ratio space. Selective element uptake by plants can thus be modelled by a downscaling of variability in the form of regression coefficients in log-ratio space. This allows to model many geochemical phenomena through a multivariate linear model in log-ratios.
To demonstrate the statistical method an exploration data set of lithologies and plant data from Northern Finland is used.
Keywords: plant geochemistry; ionome; compositional data; regression model; plant uptake; North Finland; gold mining; exploration
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Lecture (Conference)
(Online presentation)
Goldschmidt Virtual Conference 2020, 21.-26.06.2020, Online, USA
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Permalink: https://www.hzdr.de/publications/Publ-31128
Transport signatures of a junction between a quantum spin Hall System and a chiral topological superconductor
Novik, E. G.; Trauzettel, B.; Recher, P.
Abstract
We investigate transport through a normal-superconductor (NS) junction made from a quantum spin Hall (QSH) system with helical edge states and a two-dimensional (2D) chiral topological superconductor (TSC) having a chiral Majorana edge mode. We employ a two-dimensional extended four-band model for HgTe-based quantum wells in a magnetic (Zeeman) field and subject to s-wave superconductivity. We show using the Bogoliubov-de Gennes scattering formalism that this structure provides a striking transport signal of a 2D TSC. As a function of the sample width (or Fermi energy) the conductance resonances go through a sequence of 2e2/h (nontrivial phase) and 4e2/h plateaux (trivial phase) which fall within the region of a nonzero Chern number (2D limit) as the sample width becomes large. These signatures are a manifestation of the topological nature of the QSH effect and the TSC.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
-
Physical Review B 101(2020), 235308
DOI: 10.1103/PhysRevB.101.235308
Cited 4 times in Scopus -
Contribution to WWW
arXiv:1904.02984 [cond-mat.mes-hall]: https://arxiv.org/abs/1904.02984
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Enhanced Ferromagnetism and Tunable Magnetism in Fe3GeTe2 Monolayer by Strain Engineering
Hu, X.; Zhao, Y.; Shen, X.; Krasheninnikov, A.; Chen, Z.; Sun, L.
Abstract
Recent discovery of intrinsic ferromagnetism in Fe3GeTe2 (FGT) monolayer [Deng, Y.; et al. Nature 2018, 563, 94−99; Fei, Z.; et al. Nat. Mater. 2018, 17, 778−782] not only extended the family of two-dimensional (2D) magnetic materials but also stimulated further interest in the possibility to tune their magnetic properties without changing the chemical composition or introducing defects. By means of density functional theory computations, we explore strain effects on the magnetic properties of the FGT monolayer. We demonstrate that the ferromagnetism can be largely enhanced by the tensile strain in the FGT monolayer due to the competitive effects of direct exchange and superexchange interaction. The average magnetic moments of Fe atoms increase monotonically with an increase in biaxial strain from −5 to 5% in FGT monolayer. The intriguing variation of magnetic moments with strain in the FGT monolayer is related to the charge transfer induced by the changes in the bond lengths. Given the successful fabrication of the FGT monolayer, the strain-tunable ferromagnetism in the FGT monolayer can stimulate the experimental effort in this field. This work also suggests an effective route to control the magnetic properties of the FGT monolayer. The pronounced magnetic response toward the biaxial strain can be used to design the magnetomechanical coupling spintronics devices based on FGT.
Keywords: 2D materials; first-principles simulations
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 31126) publication
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ACS Applied Materials and Interfaces 12(2020), 26367-26373
DOI: 10.1021/acsami.0c05530
Cited 92 times in Scopus
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- Final Draft PDF 1,5 MB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-31126
Simulating Raman spectra by combining first-principles and empirical potential approaches with application to defective MoS2
Kou, Z.; Hashemi, A.; Puska, M.; Krasheninnikov, A.; Komsa, H.-P.
Abstract
Successful application of two-dimensional transition metal dichalcogenides in optoelectronic, catalytic, or sensing devices heavily relies on the materials’ quality, that is, the thickness uniformity, presence of grain boundaries, and the types and concentrations of point defects. Raman spectroscopy is a powerful and nondestructive tool to probe these factors but the interpretation of the spectra, especially the separation of different contributions, is not straightforward. Comparison to simulated spectra is beneficial, but for defective systems first-principles simulations are often computationally too expensive due to the large sizes of the systems involved. Here, we present a combined first-principles and empirical potential method for simulating Raman spectra of defective materials and apply it to monolayer MoS2 with random distributions of Mo and S vacancies. We study to what extent the types of vacancies can be distinguished and provide insight into the origin of different evolutions of Raman spectra upon increasing defect concentration. We apply to our simulated spectra the phonon confinement model used in previous experiments to assess defect concentrations, and show that the simplest form of the model is insufficient to fully capture peak shapes, but a good match is obtained when the type of phonon confinement and the full phonon dispersion relation are accounted for.
Keywords: Raman spectra; 2D materials; simulaitons
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 31125) publication
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npj Computational Materials 6(2020), 59
DOI: 10.1038/s41524-020-0320-y
Cited 31 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31125
Two-Pion Intensity-Interferometry in Non-Central Collisions of Au + Au @ 1.23 A GeV
Greifenhagen, R.
Abstract
High-statistics π-, π- and π+, π+ HBT data for non-central Au + Au collisions at 1.23 A GeV, measured with HADES at SIS18/GSI, are presented. The three-dimensional emission source is studied in dependence on pair transverse momentum and beam energy. A tilt of the source with respect to the reaction plane is observed. The spatial extension and the tilt magnitude of the source decrease with transverse momentum. A clear charge-sign difference is observed for the spatio-temporal variances, but not for the tilt angle of the source. Derived geometrical and temporal parameters do well complement the trend over several orders of magnitude in beam-energy provided that consistent transverse momenta are selected.
Keywords: femtoscopy; HBT
Related publications
-
Centrality determination of Au+Au collisions at 1.23A GeV with HADES
ROBIS: 26532 is cited by this (Id 31124) publication -
Identical pion intensity interferometry in central Au+Au collisions at 1.23A GeV
ROBIS: 28202 is cited by this (Id 31124) publication
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Contribution to proceedings
XIV Workshop on Particle Correlations and Femtoscopy, 03.-07.06.2019, Dubna, Russian Federation
Physics of Particles and Nuclei Volume 51, Issue 3, Berlin: Springer, 1063-7796, 288-292
DOI: 10.1134/S1063779620030132
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31124
Origin of the metamagnetic transitions in Y1− xErxFe2(H,D)4.2 compounds
Paul-Boncour, V.; Isnard, O.; Shtender, V.; Scurschii, I.; Guillot, M.
Abstract
The structural and magnetic properties of Y1−xErxFe2 intermetallic compounds and their hydrides and deuterides Y1−xErxFe2H(D)4.2 have been investigated using X-ray diffraction and magnetic measurements under static and pulsed magnetic field up to 60 T. The intermetallics crystallize in the C15 cubic structure (Fd-3m space group), whereas corresponding hydrides and deuterides crystallize in a monoclinic structure (Pc space group). All compounds display a linear decrease of the unit cell volume versus Er concentration; the hydrides have a 0.8% larger cell volume compared to the deuterides with same Er content. They are ferrimagnetic at low field and temperature with a compensation point at x=0.33 for the intermetallics and x=0.57 for the hydrides and deuterides. A sharp first order ferromagnetic-antiferromagnetic (FM-AFM) transition is observed upon heating at TFM−AFM for both hydrides and deuterides. These compounds show two different types of field induced transitions, which have different physical origin. At low temperature (T < 50 K), a forced ferri-ferromagnetic metamagnetic transition with Btrans1 ≈8 T, related to the change of the Er moments orientation from antiparallel to parallel Fe moment, is observed. Btrans1 is not sensitive to Er concentration, temperature and isotope effect. A second metamagnetic transition resulting from antiferromagnetic to ferrimagnetic state is also observed. The transition field Btrans2 increases linearly versus temperature and relates to the itinerant electron metamagnetic behavior of the Fe sublattice. An onset temperature TM0 is obtained by extrapolating TFM−AFM (B) at zero field. TM0 decreases linearly versus the Er content and is 45 ± 5 K higher for the hydrides compared to the corresponding deuteride. The evolution of TM0 versus cell volume shows that it cannot be attributed exclusively to a pure volume effect and that electronic effects should also be considered.
Involved research facilities
- High Magnetic Field Laboratory (HLD)
-
Journal of Magnetism and Magnetic Materials 512(2020), 167018
DOI: 10.1016/j.jmmm.2020.167018
Cited 6 times in Scopus
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Permalink: https://www.hzdr.de/publications/Publ-31123
Germetry dependent beam dynamics of a 3.5-cell SRF Ggun cavity at ELBE
Zhou, K.; Arnold, A.; Teichert, J.; Xiang, R.; Ma, S.; Schaber, J.
Abstract
In order to optimize the next generation SRF gun at HZDR ELBE radiation source, the impact on beam dynamics from the SRF cavity geometry needs to be investigated. This paper presents an analysis on the electromagnetic fields and output electron beam qualities, by changing the geometry parameters of a 3.5-cell SRF gun cavity. The simulation results show the higher electric field ratio in the first half cell to the TESLA like cell, the better beam parameters we can obtain, which, however, will also lead to a higher Emax/E0 and Bmax/E0.
Keywords: SRF gun; superconducting cavity
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31122) publication
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Poster
The 19th International Conference on RF Superconductivity(SRF2019), 30.06.-05.07.2019, Dresden, Germany
DOI: 10.18429/JACoW-SRF2019-THP082 -
Contribution to proceedings
The 19th International Conference on RF Superconductivity(SRF2019), 30.06.-05.07.2019, Dresden, Germany
Proceedings of the 19th International Conference on RF Superconductivity: JACoW, 978-3-95450-211-0
DOI: 10.18429/JACoW-SRF2019-THP082
Permalink: https://www.hzdr.de/publications/Publ-31122
Raw data: "Quantification of Peptide-Bound Particles: A phage Mimicking Approach via Site-Selective Immobilization on Glass"
Abstract
This set contains the raw data of the fluorescence scanning experiments used in the publication of "Quantification of peptide bound particles: A phage mimicking approach via site-selective immobilization on glass" by Schrader et al..
Related publications
- DOI: 10.1021/acsomega.1c04343 references this (Id 31121) publication
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Quantification of Peptide-Bound Particles: A Phage Mimicking Approach via …
ROBIS: 31119 has used this (Id 31121) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2021-09-27 Open access
DOI: 10.14278/rodare.357
Versions: 10.14278/rodare.1192 | 1098 | 358
License: CC-BY-4.0
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SRF Gun and SRF Linac Driven THz at ELBE Successfully in User Operation
Xiang, R.; Arnold, A.; Evtushenko, P.; Kovalev, S.; Lehnert, U.; Lu, P.; Ma, S.; Michel, P.; Murcek, P.; Ryzhov, A.; Schaber, J.; Schneider, C.; Teichert, J.; Vennekate, H.; Will, I.
Abstract
The first all-SRF accelerator driven THz source has been operated as a user facility since 2018 at ELBE radiation center. The CW electron beam is extracted from SRF gun II, accelerated to relativistic energies and compressed to sub-ps length in the ELBE SRF linac with a chicane. THz pulses are produced by passing the short electron bunches through a diffraction radiator (CDR) and an undulator. The coherent THz power increases quadratically with bunch charge. The pulse energy up to 10 μJ at 0.3 THz with 100 kHz has been generated.
Keywords: all-SRF accelerator; THz user facility; CW electron beam; SRF gun
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31120) publication
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Poster
The 19th International Conference on RF Superconductivity(SRF2019), 30.06.-05.07.2019, Dresden, Germany
DOI: 10.18429/JACoW-SRF2019-THP032 -
Contribution to proceedings
The 19th International Conference on RF Superconductivity(SRF2019), 30.06.-05.07.2019, Dresden, Germany
Proceedings of the 19th International Conference on RF Superconductivity: JACoW, 978-3-95450-211-0
DOI: 10.18429/JACoW-SRF2019-THP032
Permalink: https://www.hzdr.de/publications/Publ-31120
Quantification of Peptide-Bound Particles: A Phage Mimicking Approach via Site-Selective Immobilization on Glass
Schrader, M.; Bobeth, C.; Lederer, F.
Abstract
The increasing complexity and need of high-tech materials for modern electronics raises the demand for rare earth elements. While recycling rates are still negligible for most elements, geopolitical tensions, circular economy and the aim for a carbon neutral society puts pressure on conventional supply strategies and emphasize the need for new ideas for recycling. Our research group works on the development of phage surface display (PSD) derived peptide based recycling methods for electronic waste. This study focuses on LaPO4:Ce,Tb (LAP), a component of electronic waste from compact energy saving lamps containing rare earth elements enriched fluorescent powders. While free solution phase peptides show little to no interaction with the target material, we re-enabled the binding capability by immobilizing them on various glass supports. We shine a spotlight on the transition from phage bound to free peptides and present the first proof of successful peptide-LAP particle interactions of previously reported PSD derived sequences. Therefore, we introduce a method to investigate qualitatively and quantitatively peptide-particle-interactions. Additionally, a calibration curve allowed the quantification of peptide bound particles. Combined with the quantification of the immobilized peptide on the surface it was possible to calculate a potential dosage of peptides for future recycling processes.
Keywords: Phage Surface Display; Peptide; Immobilization; Interaction; Glass Functionalization; Binding; Particle; Fluorescent Lamp Powder; Recycling; Fluorescence scanning
Related publications
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Raw data: "Quantification of Peptide-Bound Particles: A phage Mimicking …
ROBIS: 31121 HZDR-primary research data are used by this (Id 31119) publication
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ACS Omega 7(2022)1, 187-197
Online First (2021) DOI: 10.1021/acsomega.1c04343
Cited 2 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31119
Nonlinear compositional and morphological evolution of ion irradiated GaSb prior to nanostructure formation
Lively, M. A.; Holybee, B.; Toriyama, M.; Facsko, S.; Allain, J. P.
Abstract
Low-energy ion irradiation of III-V semiconductor surfaces can lead to the formation of regular hexagonal dot patterns at the surface. We present experimental and computational results for ion irradiation of GaSb surfaces which elucidate the nature of the coupled compositional and morphological pattern-formation mechanisms. We demonstrate by in-situ grazing-incidence small-angle x-ray scattering (GISAXS) and angle-resolved Auger electron spectroscopy (ARAES) that the emergence of an altered compositional depth profile is essential to induce morphological changes at the surface. This morphological evolution of the surface follows nucleation-and-growth kinetics. Furthermore, we show from massive-scale molecular dynamics (MD) simulations that the compositional depth profile evolution leads to thermodynamic phase separation, providing a lateral compositional instability that drives pattern formation. Additionally, high-fluence simulations elucidate the irradiation-induced mechanisms of compositional depth profile formation. Prompt ion effects drive formation of single-element “protoclusters”, predominantly of Sb. Structural and energetic characterization of the simulation results indicate that Sb may be more mobile than Ga, providing a diffusional pathway for long-temporal-scale compositional evolution of the irradiated surface. Our findings motivate the development of new, comprehensive models which consider the total spatial and temporal complexity of multicomponent systems evolving under ion irradiation.
Keywords: nanostructures; ion beam irradiation; nanopatterning
Involved research facilities
- Ion Beam Center DOI: 10.17815/jlsrf-3-159
Related publications
- DOI: 10.17815/jlsrf-3-159 is cited by this (Id 31118) publication
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Scientific Reports 10(2020), 8253
DOI: 10.1038/s41598-020-64971-9
Cited 1 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31118
Preliminary geometry optimization of a 3.5-cell SRF Gun cavity at ELBE based on beam dynamics
Zhou, K.; Li, P.; Arnold, A.; Schaber, J.; Xiang, R.; Teichert, J.; Ma, S.
Abstract
At present, ELBE radiation source at HZDR is optimizing the SRF cavity for the next generation ELBE SRF GUN. This paper presents a preliminary study on the geometry optimization of a 3.5-cell SRF gun cavity based on beam dynamics. By changing the lengths of the half cell and the first TESLA like cell, two new cavity models with higher electric field in the half cell are built and their RF fields are compared with SRF GUN I and SRF GUN II. Through the scanning of the RF phases and the electric fields, the simulation results indicate that new models have smaller transverse emittance at relatively lower electric field gradients and better performance on longitudinal emittance than SRF GUN I and SRF GUN II.
Keywords: SRF cavity; SRF gun; transverse emittance
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31117) publication
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Poster
39th International Free-Electron Laser Conference (FEL19), 26.-30.08.2019, Hamburg, Germany -
Contribution to proceedings
39th International Free-Electron Laser Conference (FEL19), 26.-30.08.2019, Hamburg, Germany
Proceedings of the 39th International Free-Electron Laser Conference: JACoW, 978-3-95450-210-3
DOI: 10.18429/JACoW-FEL2019-WEP026
Permalink: https://www.hzdr.de/publications/Publ-31117
Metal and semiconductor photocathodes in HZDR SRF gun
Xiang, R.; Arnold, A.; Murcek, P.; Teichert, J.; Schaber, J.
Abstract
Quality of photocathode in a photoinjector is one of the critical issues for the stability and reliability of the whole accelerator facility. In April 2013, the IR FEL lasing was demonstrated for the first time with the electron beam from the SRF gun with Cs2Te at HZDR. Cs2Te photocathode worked in SRF gun-I for more than one year without degradation. Currently, Mg photocathodes with QE up to 0.5% are applied in SRF Gun-II, generating e- beam with bunch charge up to 300 pC in CW mode with sub-ps bunch length for the high power THz radiation. It is an excellent demonstration that SRF guns can work reliably in a high power user facility.
Keywords: photocathode; Cs2Te; Mg; photoinjector; SRF gun
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31116) publication
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Invited lecture (Conferences)
ICFA Advanced Beam Dynamics Workshop on Energy Recovery Linacs (ERL’19), 15.-20.09.2019, Berlin, Germany -
Contribution to proceedings
Workshop on Energy Recovery Linacs (ERL2019), 15.-20.09.2019, Berlin, Germany
Proceedings of workshop on Energy Recovery Linacs (ERL2019)
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31116
Robust Mg cathodes in SRF gun II
Xiang, R.; Jochen, T.
Abstract
we present here the status of ELBE SRF gun II and the application of Mg photocathodes in SRF gun. In order to improve the QE of Mg cathodes, we appy the ps- UV laser cleaning for bulk Mg photocathodes. Furthermore, several alternative preparation methods of Mg are also under studying.
Keywords: Mg photocathode; SRF gun; laser cleaning
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31115) publication
-
Invited lecture (Conferences)
European Workshop on Photocathodes for Particle Accelerator Applications (EWPAA 2019), 11.-13.09.2019, Villigen PSI, Switzerland
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31115
Development and Implementation of Beam-Based Feedback Algorithms for Continuous Wave Superconducting Linear Accelerators
Maalberg, A.; Zenker, K.; Schwarz, A.; Evtushenko, P.; Kuntzsch, M.
Abstract
The superconducting linear accelerator ELBE at Helmholtz-Center Dresden-Rossendorf is a versatile light source operated in continuous wave mode. New experiments and beam modes have a higher demand on the beam stability and reproducibility of accelerator settings. These requirements are addressed by an upgrade of the existing digital MicroTCA.4 based LLRF control by a beam-based feedback scheme. This poster gives an overview of the current control scheme, presents the planned beam diagnostics and discusses the possible ways of incorporating the beam-based feedback at the ELBE facility and a future light source.
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31114) publication
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Poster
19th International Conference on RF Superconductivity, 04.07.2019, Dresden, Germany
Permalink: https://www.hzdr.de/publications/Publ-31114
Spectral and spatial shaping of laser-driven proton beams using a pulsed high-field magnet beamline
Brack, F.-E.; Kroll, F.; Gaus, L.; Bernert, C.; Beyreuther, E.; Cowan, T.; Karsch, L.; Kraft, S.; Kunz-Schughart, L. A.; Leßmann, E.; Metzkes-Ng, J.; Obst-Hübl, L.; Pawelke, J.; Rehwald, M.; Schlenvoigt, H.-P.; Schramm, U.; Sobiella, M.; Rita Szabó, E.; Ziegler, T.; Zeil, K.
Abstract
ntense laser-driven proton pulses, inherently broadband and highly divergent, pose a challenge to established beamline concepts on the path to application-adapted irradiation field formation, particularly for 3D. Here we experimentally show the successful implementation of a highly efficient (50% transmission) and tuneable dual pulsed solenoid setup to generate a homogeneous (laterally and in depth) volumetric dose distribution (cylindrical volume of 5 mm diameter and depth) at a single pulse dose of 0.7 Gy via multi-energy slice selection from the broad input spectrum. The experiments were conducted at the Petawatt beam of the Dresden Laser Acceleration Source Draco and were aided by a predictive simulation model verified by proton transport studies. With the characterised beamline we investigated manipulation and matching of lateral and depth dose profiles to various desired applications and targets. Using an adapted dose profile, we performed a first proof-of-technical-concept laser-driven proton irradiation of volumetric in-vitro tumour tissue (SAS spheroids) to demonstrate concurrent operation of laser accelerator, beam shaping, dosimetry and irradiation procedure of volumetric biological samples.
Keywords: Laser acceleration; Radiobiology; High field pulsed magnets
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Scientific Reports 10(2020), 9118
DOI: 10.1038/s41598-020-65775-7
Cited 36 times in Scopus -
Lecture (Conference)
(Online presentation)
BLIN4: Beam Line and INstrumentation: Fourth Workshop, 29.06.2020, Dresden, Deutschland -
Lecture (Conference)
(Online presentation)
LIGHT Collaboration Meeting, 30.06.2020, Dresden, Deutschland
Permalink: https://www.hzdr.de/publications/Publ-31113
The attempt of using GaN as a photocathode in SRF Gun II
Schaber, J.; Xiang, R.; Teichert, J.; Arnold, A.; Murcek, P.; Zwartek, P.; Ma, S.
Abstract
The photocathodes determine the beam quality in linear accelerators and represent a key component for many accelerator projects. Free-electron lasers (FEL), synchrotron- and THz radiation sources require injector systems with high brightness electron beams.
High quantum efficiency, a long lifetime and good vacuum stability, fast response time and low thermal emittance are desirable parameters for a perfect photocathode used in accelerators. Semiconductors such as GaN and GaAs as novel materials for photocathodes are showing an enormous potential.
GaAs is a well-known material for photocathodes. After activation with caesium and oxygen, it has a high QE for visible light (red or green). An advantage of GaAs is the opportunity of the layers to emit spin-polarized electrons.
GaN is a semi-conductive material and well known for its high QE when lighted with UV light. For improving the QE only caesium for activation is required.
At the moment GaN is used for photocathode-based detectors such as photomultipliers or phototubes and for LEDs. They have characteristics of low dark current, high-speed response and high sensitivity. It is very new for application in SRF Guns. It seems to be more robust and achieves higher QE than other photocathodes [1].
GaN is a semi-conductive material that is well known for its high QE when lighted with UV light. For improving the QE only caesium for activation is required. It has also a wide wavelength range from 100 to 380 nm.
Doping elements for n-type is silicon (Si) and for p-type magnesium (Mg). Mostly p-doped GaN promises better conditions because magnesium atoms increase the minority carrier diffusion length (about 200 nm). MOVPE is the most used technique to produce p-type GaN. Low temperatures are required in comparison to undoped or n-type GaN. Afterwards an annealing process is necessary to remove magnesium-bonded hydrogen. In p-type GaN electron are the minority carriers whereas holes are the majority carriers. The doping is assumed to lower the band bending around the surface. Therefore, the vacuum level is shifted to lower energy than the conductive band minimum in the flat band region.
Activated with a thin alkali metal layer, like caesium, GaN has the ability to lower the surface work function to produce a negative electron affinity (NEA). This effect originates from the surface band bending. Electrons excite over the bandgap and can easily enter into the vacuum.
Crystallinity and surface parameters define the photoemission properties. Modern analytical methods are used for identification of impurities, dislocations and characterization of the crystallinity of the semiconductors and the right cleaning treatment as well as the right caesium rating.
Like caesium telluride cathode it is possible to recover GaN(Cs) about 50% of the original QE with a simple bake out of 200°C and doing a Cs-reactivation to recover the degraded
cathode [2].
A big advantage of visible light cathodes instead of UV cathodes is to relax the drive laser requirements.
[1] Uchiyama, Shoichi et al. 2011. “GaN-Based Photocathodes with Extremely High Quantum Efficiency” 103511(2005):1–4.
[2] Siegmund, O. et al. 2006. “Development of GaN Photocathodes for UV Detectors.” 567:89–92
Keywords: GaN(Cs) photocathode; III-V semiconductor; NEA photocathode; thin layer deposition
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31112) publication
-
Lecture (Conference)
ECASIA 2019-European Conference on Applications of Surface and Interface Analysis, 15.-20.09.2019, Dresden, Deutschland
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31112
Emittance measurements comparison of slit-scan and quadrupole scan in simulation and experiments
Ma, S.; Arnold, A.; Evtushenko, P.; Ryzhov, A.; Schaber, J.; Teichert, J.; Xiang, R.
Abstract
Three quadrupoles and one screen are used for beam transverse emittance measurements at HZDR ELBE. In this paper, the emittance calculated with two different methods, one with thin-lens approximation and the other one thick-lens no approximation, are compared and analized. To analyze the measurement error, quadrupole calibration is need. Two aspects about quadrupole analysis are made. The first one is quadrupole’s effective length and strength and the second one is quadrupole’s converged or diverged ability in reality.
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31111) publication
-
Poster
The 19th International Conference on RF Superconductivity, SRF2019, 30.06.-05.07.2019, Dresden, Germany
Permalink: https://www.hzdr.de/publications/Publ-31111
Study of using GaN(Cs) as a photocathode in SRF injector
Schaber, J.; Xiang, R.; Teichert, J.; Murcek, P.; Zwartek, P.; Arnold, A.; Ma, S.
Abstract
The photocathodes determine the beam quality in linear accelerators and represent a key component for many accelerator projects. Free-electron lasers (FEL), synchrotron- and THz radiation sources require injector systems with high brightness electron beams.
High quantum efficiency, a long lifetime and good vacuum stability, fast response time and low thermal emittance are desirable parameters for a perfect photocathode used in accelerators. Semiconductors such as GaN and GaAs as novel materials for photocathodes are showing an enormous potential.
GaAs is a well-known material for photocathodes. After activation with caesium and oxygen, it has a high QE for visible light (red or green). An advantage of GaAs is the opportunity of the layers to emit spin-polarized electrons.
GaN is a semi-conductive material and well known for its high QE when lighted with UV light. For improving the QE only caesium for activation is required.
At the moment GaN is used for photocathode-based detectors such as photomultipliers or phototubes and for LEDs. They have characteristics of low dark current, high-speed response and high sensitivity. It is very new for application in SRF Guns. It seems to be more robust and achieves higher QE than other photocathodes [1].
Crystallinity and surface parameters define the photoemission properties. Modern analytical methods are used for identification of impurities, dislocations and characterization of the crystallinity of the semiconductors and the right cleaning treatment as well as the right caesium rating.
[1] Uchiyama, Shoichi et al. 2011. “GaN-Based Photocathodes with Extremely High Quantum Efficiency” 103511(2005):1–4.
Keywords: GaN photocathode; caesium activation; thin layer deposition, NEA photocathode
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31110) publication
-
Poster
19th International Conference on RF Superconductivity, SRF2019, 30.06.-05.07.2019, Dresden, Deutschland
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31110
The attempt of using GaN(Cs) in SRF injector
Schaber, J.; Xiang, R.; Teichert, J.; Murcek, P.; Zwartek, P.; Arnold, A.; Ma, S.
Abstract
The photocathodes determine the beam quality in linear accelerators and represent a key component for many accelerator projects. Free-electron lasers (FEL), synchrotron- and THz radiation sources require injector systems with high brightness electron beams.
High quantum efficiency, a long lifetime and good vacuum stability, fast response time and low thermal emittance are desirable parameters for a perfect photocathode used in accelerators. Semiconductors such as GaN and GaAs as novel materials for photocathodes are showing an enormous potential.
GaAs is a well-known material for photocathodes. After activation with caesium and oxygen, it has a high QE for visible light (red or green). An advantage of GaAs is the opportunity of the layers to emit spin-polarized electrons.
GaN is a semi-conductive material and well known for its high QE when lighted with UV light. For improving the QE only caesium for activation is required.
At the moment GaN is used for photocathode-based detectors such as photomultipliers or phototubes and for LEDs. They have characteristics of low dark current, high-speed response and high sensitivity. It is very new for application in SRF Guns. It seems to be more robust and achieves higher QE than other photocathodes [1].
Crystallinity and surface parameters define the photoemission properties. Modern analytical methods are used for identification of impurities, dislocations and characterization of the crystallinity of the semiconductors and the right cleaning treatment as well as the right caesium rating.
[1] Uchiyama, Shoichi et al. 2011. “GaN-Based Photocathodes with Extremely High Quantum Efficiency” 103511(2005):1–4.
Keywords: GaN; NEA activation; photocathode; thin layer deposition
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31109) publication
-
Poster
EWPAA 2019: European workshop on photocathodes for particle accelerator applications, 11.-13.09.2019, Villingen, Schweiz
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31109
Study of surface cleaning and Cs-activation on GaN photocathodes
Schaber, J.; Xiang, R.; Teichert, J.; Arnold, A.; Murcek, P.; Zwartek, P.; Ma, S.
Abstract
Free-electron lasers (FEL), synchrotron- and THz radiation sources require injector systems with high brightness electron beams. With such a high intensity and short wavelengths, amorphous materials and chemical reaction steps nowadays could be studied.
GaN is a semi-conductive material that is well known for its high QE when lighted with UV light. For improving the QE only caesium for activation is required.
At the moment GaN is only used for photocathode-based detectors such as photomultipliers or phototubes and for LEDs. They have characteristics of low dark current, high-speed response and high sensitivity. It is very new for application in SRF Guns. It seems to be more robust and achieves higher QE than other photocathodes [1].
It has also a wide wavelength range from 100 to 380 nm.
The equilibrium phase of GaN is wutzite, which means gallium atoms are tetrahedrically surrounded by nitride atoms in a hexagonal closed crystal structure. The tetrahedrons build alternating bilayers of Ga and N in c-direction.
Doping elements for n-type is silicon (Si) and for p-type magnesium (Mg). Mostly p-doped GaN promises better conditions because magnesium atoms increase the minority carrier diffusion length (about 200 nm). MOVPE is the most used technique to produce p-type GaN. Low temperatures are required in comparison to undoped or n-type GaN. Afterwards an annealing process is necessary to remove magnesium-bonded hydrogen. In p-type GaN electron are the minority carriers whereas holes are the majority carriers. The doping is assumed to lower the band bending around the surface. Therefore, the vacuum level is shifted to lower energy than the conductive band minimum in the flat band region.
Activated with a thin alkali metal layer, like caesium, GaN has the ability to lower the surface work function to produce a negative electron affinity (NEA). This effect originates from the surface band bending. Electrons excite over the band gap and can easily enter into the vacuum.
Generally, the stability has also a great influence on the potential application in high brightness guns. GaN shows the promise of more significant stability and robustness against vacuum contaminations than alternate photocathodes.
Like caesium telluride cathode it is possible to recover GaN(Cs) about 50% of the original QE with a simple bake out of 200°C and doing a Cs-reactivation to recover the degraded
cathode [2].
[1] Uchiyama, Shoichi et al. 2011. “GaN-Based Photocathodes with Extremely High Quantum Efficiency GaN-Based Photocathodes with Extremely High Quantum Efficiency.” 103511(2005):1–4.
[2] Siegmund, O. et al. 2006. “Development of GaN Photocathodes for UV Detectors.” 567:89–92.
Keywords: photocathode; GaN; NEA activation
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31108) publication
-
Poster
DPG Summer school 2019- Exciting nanostructures: Characterizing advanced confined systems, 22.-27.07.2019, Bad Honnef, Deutschland
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31108
The attempt of using GaN (Cs) as a photocathode in SRF injector
Schaber, J.; Xiang, R.; Teichert, J.; Arnold, A.; Murcek, P.; Zwartek, P.; Ma, S.
Abstract
The photocathodes determine the beam quality in linear accelerators and represent a key component for many accelerator projects. Free-electron lasers (FEL), synchrotron- and THz radiation sources require injector systems with high brightness electron beams.
High quantum efficiency, a long lifetime and good vacuum stability, fast response time and low thermal emittance are desirable parameters for a perfect photocathode used in accelerators. Semiconductors such as GaN and GaAs as novel materials for photocathodes are showing an enormous potential.
GaAs is a well-known material for photocathodes. After activation with caesium and oxygen, it has a high QE for visible light (red or green).
An advantage of GaAs is the opportunity of the layers to emit spin-polarized electrons.
GaN is a semi-conductive material and well known for its high QE when lighted with UV light. For improving the QE only caesium for activation is required.
At the moment GaN is used for photocathode-based detectors such as photomultipliers or phototubes and for LEDs. They have characteristics of low dark current, high-speed response and high sensitivity. It is very new for application in SRF Guns. It seems to be more robust and achieves higher QE than other photocathodes [1].
Crystallinity and surface parameters define the photoemission properties. Modern analytical methods are used for identification of impurities, dislocations and characterization of the crystallinity of the semiconductors and the right cleaning treatment as well as the right caesium rating.
[1] Uchiyama, Shoichi et al. 2011. “GaN-Based Photocathodes with Extremely High Quantum Efficiency” 103511(2005):1–4.
Keywords: photocathode; semiconductor; NEA activation; surface analysis
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31107) publication
-
Poster
DPG Frühjahrstagung, 18.-22.03.2019, München, Deutschland
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31107
The attempt of using GaN as a photocathode in SRF Gun II
Schaber, J.; Xiang, R.; Murcek, P.; Arnold, A.; Teichert, J.; Ma, S.; Zwartek, P.
Abstract
The photocathodes determine the beam quality in linear accelerators and represent a key component for many accelerator projects. Free-electron lasers (FEL), synchrotron- and THz radiation sources require injector systems with high brightness electron beams.
High quantum efficiency, a long lifetime and good vacuum stability, fast response time and low thermal emittance are desirable parameters for a perfect photocathode used in accelerators. Semiconductors such as GaN and GaAs as novel materials for photocathodes are showing an enormous potential.
GaAs is a well-known material for photocathodes. After activation with caesium and oxygen, it has a high QE for visible light (red or green). An advantage of GaAs is the opportunity of the layers to emit spin-polarized electrons.
GaN is a semi-conductive material and well known for its high QE when lighted with UV light. For improving the QE only caesium for activation is required.
At the moment GaN is used for photocathode-based detectors such as photomultipliers or phototubes and for LEDs. They have characteristics of low dark current, high-speed response and high sensitivity. It is very new for application in SRF Guns. It seems to be more robust and achieves higher QE than other photocathodes [1].
Crystallinity and surface parameters define the photoemission properties. Modern analytical methods are used for identification of impurities, dislocations and characterization of the crystallinity of the semiconductors and the right cleaning treatment as well as the right caesium rating.
[1] Uchiyama, Shoichi et al. 2011. “GaN-Based Photocathodes with Extremely High Quantum Efficiency” 103511(2005):1–4.
Involved research facilities
- Radiation Source ELBE DOI: 10.17815/jlsrf-2-58
- SRF Gun
Related publications
- DOI: 10.17815/jlsrf-2-58 is cited by this (Id 31106) publication
-
Lecture (Conference)
5. Annual MT Meeting, 04.-07.03.2019, Jena, Deutschland
Downloads
Permalink: https://www.hzdr.de/publications/Publ-31106
KLOE hadronic cross section data in the HepDATA repository
Abstract
Presentation at (remote) Kick-Off-Meeting of the PrecisionSM-Working group of the STRONG2020 EU Project.
Keywords: KLOE; HEPdata
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Lecture (Conference)
(Online presentation)
Kick-Off meeting for PrecisionSM working group of STRONG2020 project, 03.06.2020, ZOOM (Sweden), Sweden
Permalink: https://www.hzdr.de/publications/Publ-31105
Dataset for dynamic simulation of the CEFR control rod drop experiments
Abstract
Dataset for dynamic simulation of the CEFR control rod drop experiments
Related publications
- DOI: 10.1016/j.anucene.2020.107707 references this (Id 31104) publication
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CEFR control rod drop transient simulation using RAST-F code system
ROBIS: 37426 has used this (Id 31104) publication of HZDR-primary research data -
Dynamic simulation of the CEFR control rod drop experiments with the Monte …
ROBIS: 31096 has used this (Id 31104) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2020-06-03 Closed access
DOI: 10.14278/rodare.353
Versions: 10.14278/rodare.354
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Permalink: https://www.hzdr.de/publications/Publ-31104
Biomineralization of uranium-phosphates fueled by microbial 1 degradation of isosaccharinic acid (ISA)
Kuippers, G.; Morris, K.; Townsend, L. T.; Bots, P.; Kvashnina, K.; Bryan, N.; Lloyd, J. R.
Abstract
Geological disposal is the preferred long-term solution for higher activity radioactive wastes (HAW) including Intermediate Level Waste (ILW). In a cementitious disposal system, cellulosic waste items present in ILW could undergo alkaline hydrolysis, producing significant quantities of isosaccharinic acid (ISA), a chelating agent for radionuclides. Although microbial degradation of ISA has been demonstrated, its impact upon the fate of radionuclides in a GDF is a topic of ongoing research. This study investigates the fate of U(VI) in pH neutral, anoxic, microbial enrichment cultures, approaching conditions similar to the far field of a GDF, containing ISA as the sole carbon source, and elevated phosphate concentrations, incubated both (i) under fermentation and (ii) Fe(III)-reducing conditions. In the fermentation experiment, U(VI) was precipitated as insoluble U(VI)-phosphates, whereas under Fe(III)-reducing conditions, the majority of the uranium was precipitated as reduced U(IV)-phosphates, potentially via enzymatic reduction (mediated by metal-reducing bacteria including Geobacter species detected by 16S rRNA gene sequencing). Overall, this suggests the potential for the establishment of a microbially-mediated “bio-barrier” extending into the far field geosphere surrounding a GDF which has the potential to evolve in response to aspects of a GDF and can have a controlling impact on the fate of radionuclides.
Involved research facilities
- Rossendorf Beamline at ESRF DOI: 10.1107/S1600577520014265
Related publications
- DOI: 10.1107/S1600577520014265 is cited by this (Id 31103) publication
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Environmental Science & Technology 55(2021)8, 4597-4606
DOI: 10.1021/acs.est.0c03594
Cited 13 times in Scopus
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- Final Draft PDF 954 kB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-31103
ESFR-SMART WP1.2.1 dataset
Abstract
ESFR-SMART WP1.2.1 dataset
Related publications
- DOI: 10.1115/1.4048905 references this (Id 31102) publication
- DOI: 10.1115/1.4048765 references this (Id 31102) publication
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Evaluation of the ESFR End of Equilibrium Cycle State: Spatial Distributions …
ROBIS: 32429 has used this (Id 31102) publication of HZDR-primary research data -
Neutronic analysis of the European Sodium Fast Reactor: Part I - fresh core …
ROBIS: 31097 has used this (Id 31102) publication of HZDR-primary research data -
Evaluation of the ESFR End of Cycle State and Detailed Spatial Distributions …
ROBIS: 29935 has used this (Id 31102) publication of HZDR-primary research data -
Neutronic analysis of the European Sodium Fast Reactor: Part II - burnup results
ROBIS: 31098 has used this (Id 31102) publication of HZDR-primary research data
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Reseach data in the HZDR data repository RODARE
Publication date: 2020-06-03 Closed access
DOI: 10.14278/rodare.351
Versions: 10.14278/rodare.352
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Permalink: https://www.hzdr.de/publications/Publ-31102
Helmholtz AI For Matter at Helmholtz-Zentrum Dresden-Rossendorf
Abstract
This poster summarizes the Helmholtz AI local unit for Matter Research installed at HZDR. The poster was presented at the Helmholtz AI Kick-Off Meeting on March 5th, 2020, in Munich, Germany.
Keywords: Helmholtz AI; FWCC; Deep Learning; Machine Learning; Data Science; Kick-Off
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Poster
(Online presentation)
Helmholtz AI Kick-Off Meeting, 05.03.2020, München, Deutschland
Permalink: https://www.hzdr.de/publications/Publ-31099
Neutronic analysis of the European Sodium Fast Reactor: Part II - burnup results
Fridman, E.; Álvarez-Velarde, F.; Romojaro-Otero, P.; Tsige-Tamirat, H.; Jiménez-Carrascosa, A.; García-Herranz, N.; Bernard, F.; Gregg, R.; Krepel, J.; Massara, S.; Poumerouly, S.; Girardi, E.; Mikityuk, K.
Abstract
In the framework of the Horizon 2020 project ESFR-SMART, the European Sodium Fast Reactor (ESFR) core was updated through a safety-related modification and optimization of the core design from the earlier FP7 CP-ESFR project.
This study is dedicated to neutronic analysis of the new SFR core. The conducted work is reported in two parts. Part I dealt with the evaluation of the safety-related neutronic parameters of the fresh core carried out by 8 organizations using both continuous energy Monte Carlo and deterministic computer codes. A special emphasis was put on the calibration and verification of the computational tools involved in the analyses.
Part II is devoted to once-through and realistic batch-wise burnup calculations aiming at the establishing of the equilibrium core state, which will later serve as a basis for detailed safety analyses.
Keywords: ESFR; safety; Horizon 2020
Related publications
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ESFR-SMART WP1.2.1 dataset
ROBIS: 31102 HZDR-primary research data are used by this (Id 31098) publication
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Journal of Nuclear Engineering and Radiation Science 8(2022)1, 011302
Online First (2021) DOI: 10.1115/1.4048765
Cited 8 times in Scopus
Downloads
- Final Draft PDF 1,7 MB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-31098
Neutronic analysis of the European Sodium Fast Reactor: Part I - fresh core results
Fridman, E.; Álvarez-Velarde, F.; Romojaro-Otero, P.; Tsige-Tamirat, H.; Jiménez-Carrascosa, A.; García-Herranz, N.; Bernard, F.; Gregg, R.; Krepel, J.; Massara, S.; Poumerouly, S.; Girardi, E.; Mikityuk, K.
Abstract
In the framework of the Horizon 2020 project ESFR-SMART (2017-2021), the European Sodium Fast Reactor (ESFR) core was updated through a safety-related modification and optimization of the core design from the earlier FP7 CP-ESFR project (2009-2013).
This study is dedicated to neutronic analyses of the improved ESFR core design. The conducted work is reported in two parts. Part I deals with the evaluation of the safety-related neutronic parameters of the fresh Beginning-of-Life (BOL) core carried out by 8 organizations using both continuous energy Monte Carlo and deterministic computer codes. In addition to the neutronics characterization of the core, a special emphasis was put on the calibration and verification of the computational tools involved in the analyses.
Part II is devoted to once-through and realistic batch-wise burnup calculations aiming at the establishing of the equilibrium core state, which will later serve as a basis for detailed safety analyses.
Keywords: ESFR; Safety; Horizon 2020
Related publications
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ESFR-SMART WP1.2.1 dataset
ROBIS: 31102 HZDR-primary research data are used by this (Id 31097) publication
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Journal of Nuclear Engineering and Radiation Science 8(2022)1, 011301
Online First (2021) DOI: 10.1115/1.4048905
Cited 9 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-31097
Dynamic simulation of the CEFR control rod drop experiments with the Monte Carlo code Serpent
Abstract
The China Experimental Fast Reactor (CEFR) is the first SFR operated in China. The CEFR physical start-up tests, conducted in 2010, included control rod (CR) worth (CRW) measurements by the rod drop method.
In this study, the transient simulations of the actual course of the CR drop experiments have been performed with the Monte Carlo code Serpent using a detailed 3D heterogeneous model of the CEFR core. The estimated time-depended neutron population, dynamic reactivity, and CRWs have been compared to the measurements. The experimental and calculated reactivity curves have shown a very close behavior for the entire simulated time interval. With regard to the CRW results, a very good compliance between the experiment and simulations as well as among the applied computational approaches has been observed. The obtained results indicate that Serpent can be routinely applied to transient simulations, the area which until recently was limited to deterministic methods.
Keywords: CEFR; Serpent; dynamic Monte Carlo; rod drop experiments
Related publications
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Dataset for dynamic simulation of the CEFR control rod drop experiments
ROBIS: 31104 HZDR-primary research data are used by this (Id 31096) publication
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Annals of Nuclear Energy 148(2020), 107707
DOI: 10.1016/j.anucene.2020.107707
Cited 9 times in Scopus
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- Secondary publication expected
Permalink: https://www.hzdr.de/publications/Publ-31096
An improved contact method for quantifying the mixing of a binary granular mixture
Papapetrou, T. N.; Lecrivain, G.; Bieberle, M.; Boudouvis, A.; Hampel, U.
Abstract
When two granular phases are brought into motion in a rotating drum, a competition of mixing and segregation occurs. Several image analysis methods have been used to quantify the mixing. In this work, a modification of the contact method, originally proposed by Van Puyvelde (1999), is suggested to allow evaluation of the mixing index for each separate image. A strength of this modified method lies in the removal of the case-dependent normalization of the mixing index, which has so far impaired a direct comparison to other studies. This modified method is tested on artificial and experimental images of a granular bed composed of spherical glass and polypropylene beads of equal size. The bed evolves in a rotating drum under the rolling regime. The temporal evolution of the mixing index is in excellent agreement with the commonly used variance method.
Keywords: binary particle mixing; rotating drum; image analysis; mixing index; contact method; variance method
Related publications
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Code, data and supplementary material for: An improved contact method for …
ROBIS: 31602 HZDR-primary research data are used by this (Id 31095) publication
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Granular Matter 23(2021), 15
DOI: 10.1007/s10035-020-01073-3
Cited 3 times in Scopus
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- Final Draft PDF 1,4 MB Secondary publication
Permalink: https://www.hzdr.de/publications/Publ-31095
Laboratory study of stationary accretion shock relevant to astrophysical systems
Mabey, P.; Albertazzi, B.; Falize, E.; Michel, T.; Rigon, G.; van Box Som, L.; Pelka, A.; Brack, F.-E.; Kroll, F.; Filippov, E.; Gregori, G.; Kuramitsu, Y.; Lamb, D. Q.; Li, C.; Ozaki, N.; Pikuz, S.; Sakawa, Y.; Tzeferacos, P.; Koenig, M.
Abstract
Accretion processes play a crucial role in a wide variety of astrophysical systems. Of particular interest are magnetic cataclysmic variables, where, plasma flow is directed along the star’s magnetic field lines onto its poles. A stationary shock is formed, several hundred kilometres above the stellar surface; a distance far too small to be resolved with today’s telescopes. Here, we report the results of an analogous laboratory experiment which recreates this astrophysical system. The dynamics of the laboratory system are strongly influenced by the interplay of material, thermal, magnetic and radiative effects, allowing a steady shock to form at a constant distance from a stationary obstacle. Our results demonstrate that a significant amount of plasma is ejected in the lateral direction; a phenomenon that is under-estimated in typical magnetohydrodynamic simulations and often neglected in astrophysical models. This changes the properties of the post-shock region considerably and has important implications for many astrophysical studies.
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Scientific Reports 9(2019), 8157
DOI: 10.1038/s41598-019-44596-3
Cited 7 times in Scopus
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Permalink: https://www.hzdr.de/publications/Publ-31094
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