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Three-dimensional acoustic monitoring of laser-accelerated protons in the focus of a pulsed-power solenoid lens

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High Power Laser Science and Engineering 2023年第3期11卷 57-63页

作者： S.Gerlach F.Balling A.K.Schmidt F.E.Brack F.Kroll J.Metzkes-Ng M.Reimold u.schramm M.Speicher K.Zeil K.Parodi J.Schreiber Fakultät für Physik Ludwig-Maximilians-Universität MünchenGarchingGermany Helmholtz-Zentrum Dresden-Rossendorf DresdenGermany Technische universität Dresden DresdenGermany

The acoustic pulse emitted from the Bragg peak of a laser-accelerated proton bunch focused into water has recently enabled the reconstruction of the bunch energy *** adding three ultrasonic transducers and implementing a fast data analysis of the filtered raw signals,I-BEAT(Ion-Bunch Energy Acoustic Tracing)3D now provides the mean bunch energy and absolute lateral bunch position in real-time and for individual *** changes in energy spread and lateral bunch size can also be *** experiments at DRACO with proton bunch energies between 10 and 30 MeV reveal sub-MeV and sub-mm *** addition to this 3D bunch information,the signal strength correlates also with the absolute bunch particle number.

关键词： ion diagnostics ionoacoustics laser-driven plasma source laser-ion acceleration

miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider u.schramm M.E.P.umlandt K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

OCTOPOD:single-bunch tomography for angular-spectral characterization of laser-driven protons

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High Power Laser Science and Engineering 2023年第6期11卷 16-28页

作者： M.Reimold S.Assenbaum E.Beyreuther E.Bodenstein F.-E.Brack C.Eisenmann F.Englbrecht F.Kroll F.Lindner u.Masood J.Pawelke u.schramm M.Schneider M.Sobiella M.E.P.umlandt M.Vescovi K.Zeil T.Ziegler J.Metzkes-Ng Helmholtz-Zentrum Dresden-Rossendorf DresdenGermany Technische universität Dresden DresdenGermany OncoRay-National Center for Radiation Research in Oncology DresdenGermany Ludwig-Maximilians-universität München Garching/MünchenGermany universitätsklinikum Freiburg FreiburgGermany

Laser-plasma accelerated(LPA)proton bunches are now applied for research fields ranging from ultra-high-dose-rate radiobiology to material ***,the capabilities to characterize the spectrally and angularly broad LPA bunches lag behind the rapidly evolving *** OCTOPOD translates the angularly resolved spectral characterization of LPA proton bunches into the spatially resolved detection of the volumetric dose distribution deposited in a liquid *** to 24 multi-pinhole arrays record projections of the scintillation light distribution and allow for tomographic reconstruction of the volumetric dose deposition pattern,from which proton spectra may be *** the OCTOPOD at a cyclotron,we show the reliable retrieval of various spatial dose deposition patterns and detector sensitivity over a broad dose ***,the OCTOPOD was installed at an LPA proton source,providing real-time data on proton acceleration performance and attesting the system optimal performance in the harsh laser-plasma environment.

关键词： laser-plasma acceleration of protons proton detector tomographic reconstruction

ReLaX:the Helmholtz International Beamline for Extreme Fields high-intensity short-pulse laser driver for relativistic laser-matter interaction and strong-field science using the high energy density instrument at the European X-ray free electron laser fac

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High Power Laser Science and Engineering 2021年第4期9卷 144-159页

作者： A.Laso Garcia H.Höppner A.Pelka C.Bähtz E.Brambrink S.Di Dio Cafiso J.Dreyer S.Göde M.Hassan T.Kluge J.Liu M.Makita D.Möller M.Nakatsutsumi T.R.Preston G.Priebe H.-P.Schlenvoigt J.-P.Schwinkendorf M.šmíd A.-M.Talposi M.Toncian u.Zastrau u.schramm T.E.Cowan T.Toncian Helmholtz-Zentrum Dresden-Rossendorf 01328 DresdenGermany European XFEL 22869 SchenefeldGermany Extreme Light Infrastructure-Nuclear Physics and Faculty of Physics University of Bucharest077126 MagureleRomania Technische universität Dresden 01062 DresdenGermany

High-energy and high-intensity lasers are essential for pushing the boundaries of *** development has allowed leaps forward in basic research areas,including laser±plasma interaction,high-energy density science,metrology,biology and medical *** Helmholtz International Beamline for Extreme Fields user consortium contributes and operates two high-peak-power optical lasers using the high energy density instrument at the European X-ray free electron laser(EuXFEL)*** lasers will be used to generate transient extreme states of density and temperature to be probed by the X-ray *** paper introduces the ReLaX laser,a short-pulse high-intensity Ti:Sa laser system,and discusses its characteristics as available for user *** will also present the first experimental commissioning results validating its successful integration into the EuXFEL infrastructure and viability as a relativisticintensity laser driver.

关键词： X-ray free electron laser high-intensity laser relativistic intensity laser Ti:Sa laser

Targets for high repetition rate laser facilities:needs,challenges and perspectives

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High Power Laser Science and Engineering 2017年第3期5卷 10-40页

作者： I.Prencipe J.Fuchs S.Pascarelli D.W.Schumacher R.B.Stephens N.B.Alexander R.Briggs M.Büscher M.O.Cernaianu A.Choukourov M.De Marco A.Erbe J.Fassbender G.Fiquet P.Fitzsimmons C.Gheorghiu J.Hund L.G.Huang M.Harmand N.J.Hartley A.Irman T.Kluge Z.Konopkova S.Kraft D.Kraus V.Leca D.Margarone J.Metzkes K.Nagai W.Nazarov P.Lutoslawski D.Papp M.Passoni A.Pelka J.P.Perin J.Schulz M.Smid C.Spindloe S.Steinke R.Torchio C.Vass T.Wiste R.Zaffino K.Zeil T.Tschentscher u.schramm T.E.Cowan Lawrence Berkeley National Laboratory USA 25Institute of Microelectronics of Barcelona National Center of Microelectronic Spanish Research Council Spain 26University of St. Andrews UK

A number of laser facilities coming online all over the world promise the capability of high-power laser experiments with shot repetition rates between 1 and 10 Hz. Target availability and technical issues related to the interaction environment could become a bottleneck for the exploitation of such facilities. In this paper, we report on target needs for three different classes of experiments: dynamic compression physics, electron transport and isochoric heating, and laser-driven particle and radiation sources. We also review some of the most challenging issues in target fabrication and high repetition rate operation. Finally, we discuss current target supply strategies and future perspectives to establish a sustainable target provision infrastructure for advanced laser facilities.

关键词： high-energy density physics target design and fabrication

Metabolomic evidence of independent biotransformation pathways for terpenes in two specialist mammalian herbivores (genus Neotoma)

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Integrative Zoology 2024年第1期19卷 143-155页

作者： Katharina schramm Michele SKOPEC Denise DEARING Department of Biology University of UtahSalt Lake CityUtahUSA Department of Zoology Weber State UniversityOgdenUtahUSA

Herbivory is common in mammals,yet our understanding of detoxification processes used by mammals to biotrans-form plant secondary compounds(PSCs)is *** herbivores are thought to have evolved detoxifica-tion mechanisms that rely more heavily on energetically cheap Phase I biotransformation reactions to process high levels of PSCs in their *** explored this hypothesis by comparing the urinary metabolite patterns of two spe-cialist herbivores(genus Neotoma).Neotoma stephensi is an obligate specialist on one-seeded juniper(Juniperus monosperma).Neotoma lepida is a generalist forager across its range,yet populations in the Great Basin specialize on utah juniper(***).While both juniper species have high levels of terpenes,the terpene profiles and quantities differ between the *** from both woodrat species were fed diets of each juniper in a cross-over ***,collected over a 24-h period,was extracted and analyzed in an untargeted metabolomics approach using both GC-MS and HPLC-MS/*** obligate specialist *** excreted a unique pattern of Phase I metabolites when fed its native juniper,while *** excreted a unique pattern of Phase II metabolites when fed its native *** woodrat species utilized the Phase II metabolic pathway of glucuronidation more heavily when consuming the more chemically diverse ***,and *** utilized less glucuronida-tion than *** when consuming *** results are consistent with the hypothesis that obligate specialists may have evolved unique and efficient biotransformation mechanisms for dealing with PSCs in their diet.

关键词： dietary specialization herbivory juniper metabolomics Neotoma

Effects of propeller load fluctuations on performance and emission of a lean-burn natural gas engine at part-load conditions

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Propulsion and Power Research 2022年第2期11卷 196-208页

作者： S.Tavakoli J.schramm E.Pedersena Department of Marine Technology Norwegian University of Science and TechnologyTrondheimNorway Department of Mechanical Engineering Technical University of DenmarkLyngbyDenmark

Providing stable combustion of lean-burn natural gas engines was always a bigchallenge, particularly during a low load operation. In transient sea conditions, there is an additional concern due to irregular time-varying loads. Therefore, this study aimed at investigatingthe part-load operation of a marine spark-ignition lean-burn natural gas engine by simulatingthe entire engine. The engine’s essential components are modeled, including air manifold,intake valves, fuel system, controllers, combustion chamber, exhaust valves, exhaust manifoldand *** steady-state, the results of emission compounds from modeling have been compared tomeasured data from 25% to 100% loads. For transient conditions, for the sample time of about50 min, the fuel flow and turbocharger output are selected from the vessel logged data andcompared with the simulation results. The model has shown the great potential of predictingthe engine response throughout the steady-state and transient conditions. Simulating the engineat part-load transient condition showed that the unburned hydrocarbon formation, known asmethane slip in lean-burn gas engines, is more than the part-load steady-state. This increaseof methane slip is due to the combustion instability in lower loads and flame extinguishingin such transient conditions. The engine measured data shows a double amount of methane slipin a 25% load than the 100% load in steady-state. However, the simulation output in the transient conditions confirms an increase in methane slip over four times than equivalentsteady-state load. Moreover, the lean-burn gas engine releases less NOX in part-load operationin a steady-state due to lower in-cylinder temperature. In transient conditions, there is remarkable instability in excess air ratio. Due to this instability, there is a rich mixture in instantaneoustime steps during loads up. Therefore, it will result in an unusually high amount of NOX, andmore than two times in comparison with the equivalent

关键词： Lean-burn combustion Emission formation Methane slip NOX Part-load operation

Tunable colors and conductivity by electroless growth of Cu/Cu2O particles on sol-gel modified cellulose

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Nano Research 2020年第10期13卷 2658-2664页

作者： Justus Landsiedel Waleri Root Christian schramm Alexander Menzel Steffen Witzleben Thomas Bechtold Tung Pham Research Institute for Textile Chemistry and Textile Physics University of Innsbruck6850 DornbirnAustria Department of Physical Chemistry University of Innsbruck6020 InmsbruckAustria Department of Natural Sciences Bonn Rhein sSieg University of Applied Sciences5359 RheinbachGermany

Development of colored surfaces by formation of nano-structured aggregates is a widely used strategy in nature to color lightweight structures (e.g. butterflies) without the use of dye pigments. The deposition of nanoscale particles mimics nature in it’s approach coloring surfaces. This work presents sol-gel modification of cellulose surfaces used to form a template for growth of Cu/Cu2O core–shell particles with defined size-distributions. Besides improving the adhesion of the deposited particulate material, the sol-gel matrix serves as a template for the control of particle sizes of the Cu/Cu2O structures, and as a consequence of particle size variation the surface color is tunable. As an example, red color was achieved with an average particle size of 35 nm, and shifts gradually to blue appearance when particles have grown to 80 nm on the sol-gel modified fabric. The copper concentration on representative fabrics is kept low to avoid modifying the textile characteristics and were all in the range of 150–170 mg per g of cellulose material. As a result of copper deposition on the surface of the material, the cellulose fabric also became electrically conductive. Remarkably, the electrical conductivity was found to be dependent on the average particle sizes of the deposits and thus related to the change in observed color. The generation of color by growth of nano-sized particles on sol-gel templates provides a highly promising approach to stain surfaces by physical effects without use of synthetic colorants, which opens a new strategy to improve environmental profile of coloration.

关键词： electroless copper deposition sol-gel support thin film structural coloration tunable sheet resistance LSPR

Studies on Differential Nuclear Translocation Mechanism and Assembly of the Three Subunits of the Arabidopsis thaliana Transcription Factor NF-Y

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Molecular Plant 2012年第4期5卷 876-888页

作者： Dieter Hackenberg Yanfang Wu Andrea Voigt Robert Adams Peter schramm Bernhard GrimmI Institute of Biology/Plant Physiology Humboldt University Philippstr. 13 Building 12 10115 Berlin Germany

The eukaryotic transcription factor NF-Y consists of three subunits （A, B, and C）, which are encoded in Ara- bidopsis thaliana in multigene families consisting of 10, 13, and 13 genes, respectively. In principle, all potential combi- nations of the subunits are possible for the assembly of the heterotrimeric complex. We aimed at assessing the probability of each subunit to participate in the assembly of NF-Y. The evaluation of physical interactions among all members of the NF-Y subunit families indicate a strong requirement for NF-YB/NF-YC heterodimerization before the entire complex can be accomplished. By means of a modified yeast two-hybrid system assembly of all three subunits to a heterotrimeric complex was demonstrated. using GFP fusion constructs, NF-YA and NF-YC localization in the nucleus was demonstrated, while NF- YB is solely imported into the nucleus as a NF-YC-associated heterodimer NF-YC. This piggyback transport of the two Arabidopsis subunits differs from the import of the NF-Y heterotrimer of heterotrophic organisms. Based on a peptide structure model of the histone-fold-motifs, disulfide bonding among intramolecular conserved cysteine residues of NF-YB, which is responsible for the redox-regulated assembly of NF-YB and NF-YC in human and Aspergillus nidulans, can be excluded for Arabidopsis NF-YB.

关键词： gene expression transcriptional control and transcription factors nuclear translocation protein-proteininteraction.