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Stream of Reaction Products behind the Detonation Wave Front

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含能材料 2001年第1期9卷 4-7页

作者： held M (TDW,86523 Schrobenhausen, Germany) TDW 86523 Schrobenhausen 德国

Embedded copper foils in a high explosive charge allow to see the stream of the reaction products behind the detonation front. With three individual firings in front of FXR it can be shown that the reaction products behind the detonation front are immediately going in the direction of the detonation front. But then the rarefaction fans are influencing strongly the further displacements.

关键词： ZNP model reaction product rarefaction

CGR3： A Golgi-Localized Protein Influencing Homogalacturonan Methylesterification

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Molecular Plant 2011年第5期4卷 832-844页

作者： Michael A. held Evan Be Starla Zemelis Saunia Withers Curtis Wilkerson Federica Brandizzi Great Lakes Bioenergy Research Center Michigan State University East Lansing MI 48824 USA MSU-DOE Plant Research Lab Michigan State University East Lansing MI 48824 USA Present address： Department of Chemistry and Biochemistry Ohio University Athens OH 45701 USA Department of Biochemistry and Molecuiar Biology Michigan State University East Lansing MI 48824 USA

Plant cell walls are complex structures that offer structural and mechanical support to plant cells and are ultimately responsible for plant architecture and form. Pectins are a large group of complex polysaccharides of the plant cell wall that are made in the Golgi and secreted to the wall. The methylesterification of pectins is believed to be an important factor for the dynamic properties of the cell wall. Here, we report on a protein of unknown function discovered using an extensive proteomics analysis of cotton Golgi. Through bioinformatic analyses, we identified the ortholog of such protein, here named cotton Golgi-related 3 （CGR3） in Arabidopsis and found that it shares conserved residues with S- adenosylmethionine methyltransferases. We established that CGR3 is localized at the Golgi apparatus and that the expression of the CGR3 gene is correlated with that of several cell wall biosynthetic genes, suggesting a possible role of the protein in pectin modifications. Consistent with this hypothesis, immunofluorescence microscopy with antibodies for homogalacturonan pectins （HG） indicated that the celt wails of cgr3 knockout mutants and plants overexpressing CGR3 are decreased and increased in HG methylesterification, respectively. Our results suggest that CGR3 plays a role in the methylesterification of homogalacturonan in Arabidopsis.

关键词： Golgi methyltransferase homogalacturonan pectin.

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网络炸药装置爆轰研究(英文)

含能材料 2003年第1期11卷 8-12页

作者： Manfred held TDW/EADS 86523 Schrobenhausen

采用沟槽中充满炸药的V形装置,可以连续测量和分析网络炸药线之间所允许的最小距离,这个距离是炸药线和它后面相临的炸药线之间时间差的函数。通过两个例子来讨论了这种技术和方法。对于特殊的网络炸药装置,这种性能和知识是很重要的。

关键词：网络炸药装置爆轰 V形装置炸药线最小距离

A simulation study on spatial and time resolution for a cost-effective positron emission particle tracking system

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Particuology 2024年第5期88卷 312-322页

作者： Josephine Oppotsch Matthias Steinke Miriam Fritsch Fritz-Herbert Heinsius Thomas held Nikoline Hilse Viktor Scherer Ulrich Wiedner Ruhr-Universität Bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-Universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

This work is the second part of a simulation study investigating the processing of densely packed and moving granular assemblies by positron emission particle tracking (PEPT).Since medical positron emission tomography (PET) scanners commonly used for PEPT are very expensive,a PET-like detector system based on cost-effective organic plastic scintillator bars is being developed and tested for its *** this context,the spatial resolution of a resting positron source,a source moving on a freely designed model path,and a particle motion given by a discrete element method (DEM) simulation is studied using Monte Carlo simulations and the software toolkit *** not only extended the simulation and reconstruction to a moving source but also significantly improved the spatial resolution compared to previous work by adding oversampling and iteration to the reconstruction ***,in the case of a source following a trajectory developed from DEM simulations,a very good resolution of about 1 mm in all three directions and an average 3D deviation between simulated and reconstructed events of 2.3 mm could be ***,the resolution for realistic particle motion within the generic grate system (which is the test rig for further experimental studies) is well below the smallest particle *** simulation of the dependence of the reconstruction accuracy on tracer particle location revealed a nearly constant efficiency within the entire detector system,which demonstrates that boundary effects can be neglected.

关键词： Positron emission particle tracking Monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

A simulation study for a cost-effective PET-like detector system intended to track particles in granular assemblies

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Particuology 2024年第1期84卷 117-125页

作者： Josephine Oppotsch Antonios Athanassiadis Miriam Fritsch Fritz-Herbert Heinsius Thomas held Nikoline Hilse Viktor Scherer Matthias Steinke Ulrich Wiedner Ruhr-Universität Bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-Universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

Since many industrial applications rely on the processing of densely packed and moving granular ma-terial,obtaining bulk internal information on the particle movement inside the reactors is of great *** information can be delivered by Positron Emission Particle Tracking(PEPT).By marking pellets with a positron-emitting radioisotope,the position of these tracer particles can be determined via the time-of-flight differences of the emitted gamma-ray *** current paper proposes a PET-like detector system based on cost-effective organic plastic scintillators instead of the more common but expensive inorganic *** system is currently under construction and was tested for its resolution and efficiency in this simulation *** Monte Carlo simulations and the software toolkit Geant4,three different geometries(an empty glass box,a generic grate system,and a cubic box of 1 m3 completely filled with pellets)were investigated,leading to a spatial resolution in the millimeter range and an efficiency,defined as the ratio of reconstructed decay locations to simulated decays,of 2.7%,1.4%,and 0.3%.

关键词： Positron emission particle tracking Geant4 Monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

Mycorrhizal fungi mitigate nitrogen losses of an experimental grassland by facilitating plant uptake and soil microbial immobilization

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Pedosphere 2024年第2期34卷 399-410页

作者： Yangyang JIA Marcel G.A.VAN DER HEIJDEN Alain Y.VALZANO-held Markus JOCHER Florian WALDER Postdoctoral Mobile Station of Ecology College of Ecology and EnvironmentXinjiang UniversityÜrümqi 830046China Research Group Plant-Soil Interactions AgroscopeZürich 8046Switzerland Research Group Climate and Agriculture AgroscopeZürich 8046Switzerland Department of Plant and Microbial Biology University of ZürichZürich 8008Switzerland Research Group Soil Quality and Soil Use AgroscopeZürich 8046Switzerland

Nitrogen(N)is one of the most limited nutrients of terrestrial ecosystems,whose losses are prevented in tightly coupled cycles in finely tuned *** change-induced N enrichment through atmospheric deposition and application of vast amounts of fertilizer are now challenging the terrestrial N *** mycorrhizal fungi(AMF)are known drivers of plant-soil nutrient fluxes,but a comprehensive assessment of AMF involvement in N cycling under global change is still ***,we simulated N enrichment by fertilization(low/high)in experimental grassland microcosms under greenhouse conditions in the presence or absence of AMF and continuously monitored different N pathways over nine *** found that high N enrichment by fertilization decreased the relative abundance of legumes and the plant species dominating the plant community changed from grasses to forbs in the presence of AMF,based on aboveground *** presence of AMF always maintained plant N:phosphorus(P)ratios between 14 and 16,no matter how the soil N availability *** in plant N:P ratios due to the increased plant N and P uptake might thus be a primary pathway of AMF altering plant community ***,we constructed a comprehensive picture of AMF’s role in N cycling,highlighting that AMF reduced N losses primarily by mitigating N leaching,while N_(2)O emissions played a marginal *** mycorrhizal fungi reduced N_(2)O emissions directly through the promotion of N_(2)O-consuming *** underlying mechanism for reducing N leaching is mainly the AMF-mediated improved nutrient uptake and AMF-associated microbial *** results indicate that synergies between AMF and other soil microorganisms cannot be ignored in N cycling and that the integral role of AMF in N cycling terrestrial ecosystems can buffer the upcoming global changes.

关键词： N cycling N enrichment N uptake N:P ratio plant community structure symbiotic soil fungi

Defeating Mechanisms of Armours for Main Battle Tanks

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Defence Technology（防务技术） 2005年第1期1卷 1-9页

作者： Manfred held TDW/EADS 86523 Schrobenhausen Germany

The fundamental protection principles of the new armours for main battle tanks against kinetic energy projectiles (KE) and chemical energy weapons (CE)--shaped charges are shortly described and their efficiency against both threats discussed. The armour topics can be split into: "perpendicular or zero-degree armours", such as rolled homogeneous armour (RHA), also with extremely high strength, ceramics, glass, liquid filled columns and explosive filled cells,"inclined armours", as spaced RHA plates with their corner effects, bulging armour, additive and integrated explosive reactive armours (ERA) and "hard kill active defence possibilities" in different defeating distances.

关键词：主战坦克被动装甲反应装甲主动防御

Overview of Anti-tank Mines

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Defence Technology（防务技术） 2006年第1期2卷 22-32页

作者： Manfred held TDW/EADS Schrobenhausen 86523 Germany

First the different anti-tank mines laying possibilities are shortly summarized: hand emplaced, with mine layers, ground or helicopter relatively topographical well defined, and with cluster systems of projectiles, rockets and aircraft dispensers. Then examples of the three generations of anti-tank mines are presented:Ⅰ generation: detonating only beneath the track; Ⅱ generation: detonating beneath the track and belly;Ⅲ generation: mines with off-route actions. Weight and cost comparisons are strongly favoring the off-route Ⅲ-generation mines.

关键词：坦克生产系统重量成本

Circle of Willis variants are not associated with thrombectomy outcomes

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Stroke & Vascular Neurology 2021年第2期6卷 310-313页

作者： Thomas Seifert-held Katharina Eberhard Soren Christensen Edith Hofer Christian Enzinger Gregory W Albers Maarten Lansberg Department of Neurology Medical University of GrazGrazAustria Core Facility Computational Bioanalytics Center for Medical ResearchMedical University of GrazGrazAustria Department of Neurology&Neurological Sciences Stanford UniversityStanfordCaliforniaUSA

Background The circle of Willis(COW)is part of the brain collateral *** absence of COW segments may affect functional outcome in patients with ischaemic stroke undergoing endovascular *** In 182 patients in the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution 2 Study and the CT Perfusion to Predict Response to Recanalisation in Ischaemic Stroke Project,COW anatomy was evaluated on postinterventional magnetic resonance *** absence of the posterior communicating artery or the first segments of posterior or anterior cerebral arteries ipsilateral to the ischaemic infarction was rated as an incomplete *** regression was applied to evaluate an association with the patients’modified Rankin scale(mRS)at 90 days after stroke Results An incomplete ipsilateral COW was not predictive of the patients’mRS at 90 days after *** associations were shown for the patients’baseline National Institutes of Health Stroke Scale(NIHSS),age and reperfusion *** effect size suggests that a significant association of an incomplete COW with the mRS at 90 days may be obtained in cohorts of more than 3000 *** Compared with the established predictors NIHSS,age and reperfusion status,an incomplete COW is not associated with functional outcome after endovascular therapy.

关键词： Willis anatomy incomplete