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Deuterium retention in chemically vapor deposited tungsten carbide coatings and hot-rolled tungsten exposed to low-energy deuterium plasma

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Tungsten 2022年第1期4卷 10-19页

作者： Vladimir Kh.Alimov joachim Roth Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of SciencesMoscow 119071Russia Max-Planck-Institut fur Plasmaphysik 85748 GarchingGermany

Samples of chemically vapor deposited(CVD)coatings of tungsten carbides W_(45)C_(55)and W_(60)C_(40)and samples of hot-rolled tungsten were exposed to deuterium(D)plasma at sample temperatures ranging from 323 to 813 K,as a result of which the samples were irradiated with D ions with an energy of about 200 eV per D particle at a flux of D particles of about1.1×10^(21)D·m^(-2)·s^(-1)to a fluence of about 2×10^(24)D·m^(-2).The concentration of deuterium in these samples was examined by the D(3 He,p)4 He nuclear *** on the measured deuterium depth profiles and assuming that these profiles are determined by diffusing D atoms,the diffusion coefficients of deuterium in the CVD tungsten carbide coatings were *** these diffusion coefficients,an estimate of the Arrhenius relation for the diffusion coefficients of deuterium in CVD tungsten carbide coatings was obtained:D=2.5×10^(-3)exp(-1.12 eV/kT)m~2·s^(-1),where T is temperature expressed in Kelvin,and k is the Boltzmann *** concentration of trapped deuterium in the bulk of CVD tungsten carbide coatings is practically independent of the stoichiometry of the *** decreases from about 5×10^(-2)to about 7×10^(-4)D/(W+C)with an increase in the deuterium plasma exposure temperature from 373 to 813 *** concentration of trapped deuterium in hot-rolled tungsten,expressed in units of the D/W atomic ratio,is more than an order of magnitude lower than the concentration of deuterium in tungsten carbides,and also decreases with increasing plasma exposure temperature.

关键词： Chemically vapor deposited tungsten carbides Tungsten Deuterium plasma Deuterium depth profiles Deuterium diffusion coefficients

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Evaluation of factors influencing soluble microbial product in submerged MBR through hybrid ASM model

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Frontiers of Environmental Science & Engineering 2009年第2期3卷 226-235页

作者： Fangyue LI joachim BEHRENDT Knut WICHMANN Ralf OTTERPOHL Institute of Water Resources and Water Supply Hamburg University of TechnologySchwarzenbergstr.95 ED-21073 HamburgGermany Department of Wastewater Management Hamburg University of TechnologyEissendorfer Strasse 42D-21073 HamburgGermany

In this study,a mathematical model was established to predict the formation of the soluble microbial product(SMP)in a submerged membrane *** developed model was calibrated under the reference *** results were in good agreement with the measured results under the reference *** calibrated model was then used in the scenario studies to evaluate the effect of three chosen operating parameters:hydraulic retention time(HRT),dissolved oxygen concentration,and sludge retention time(SRT).Simulation results revealed that the SMP dominated the soluble organic substances in the *** scenario studies also revealed that the HRT can be decreased to 1 h without deteriorating the effluent quality;dissolved oxygen concentration in the reactor can be kept at 2–3 mg/L to maintain the effluent quality,reduce the content of SMP,and minimize operating costs;the optimal SRT can be controlled to 10–15 d to achieve complete nitrification process,less membrane fouling potential,and acceptable organic removal efficiency.

关键词： hybrid activated sludge model(ASM) membrane bioreactor(MBR) soluble microbial product(SMP)

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Electrochemically driven conversion reaction in fluoride electrodes for energy storage devices

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npj Computational Materials 2018年第1期4卷 462-476页

作者： Chilin Li Keyi Chen Xuejun Zhou joachim Maier State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050China University of Chinese Academy of Sciences Beijing 100039China Max Planck Institute for Solid State Research Heisenbergstraße 1D-70569 StuttgartGermany

Exploring electrochemically driven conversion reactions for the development of novel energy storage materials is an important topic as they can deliver higher energy densities than current Li-ion battery ***-type fluorides promise particularly high energy densities by involving the light and small fluoride anion,and bond breaking can occur at relatively low Li activity(i.e.,high cell voltage).Cells based on such electrodes may become competitors to other envisaged alternatives such as Lisulfur or Li-air systems with their many unsolved thermodynamic and kinetic *** conversion reactions are typically multiphase redox reactions characterized by nucleation and growth processes along with pronounced interfacial and mass transport *** significant overpotentials and nonequilibrium reaction pathways are *** this review,we summarize recent findings in terms of phase evolution phenomena and mechanistic features of(oxy)fluorides at different redox stages during the conversion process,enabled by advanced characterization technologies and simulation *** can be concluded that well-designed nanostructured architectures are helpful in mitigating kinetic problems such as the usually pronounced voltage *** this context,doping and open-framework strategies are *** these tools,simple materials that are unable to allow for substantial Li nonstoichiometry(e.g.,by Li-insertable channels)may be turned into electroactive materials.

关键词： fluoride energy breaking

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Direct Measurement of CO_2 Retention in Arable Soils with pH Above 6.5 During Barometric Process Separation Incubation

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Pedosphere 2018年第5期28卷 726-738页

作者： Hannah CONRADS joachim INGWERSEN JU Xiaotang Thilo STRECK Institute of Soil Science and Land Evaluation Biogeophysics SectionUniversity of Hohenheim College of Agricultural Resources and Environmental Sciences China Agricultural University

The barometric process separation(BaPS)technique is a well-established incubation method to simultaneously measure gross nitrification and respiration rates in *** application,however,is still critical in soils with pH above ***,a substantial part of microbial CO_2 production is retained in soil solution(CO_2,aq)due to shifts in the carbonate *** may lead to substantial errors in gas balance ***,utilization of the BaPS technique is only reliable if the critical term is adequately *** present an easy,inexpensive,and direct method,the sterilization-CO_2-injection(SCI)method,to measure CO_2 retention during soil *** soil was incubated in the BaPS system,and defined volumes of CO_2 were injected to stepwise increase CO_2partial pressure(p CO_2)inside the chamber and to analyse the physicochemical equilibration *** exemplary agricultural soils from Northeast China and Southwest Germany were used for method establishment,presenting pH values between 4.4 and 7.6 and carbonate contents between 0% and 3.9%.We observed that in soils with pH>6.5,70%–90% of the injected CO_2 was taken up by the soil until the equilibrium inside the chamber was *** expected,in soils with low pH(<6.5),measured CO_2 retention was ***_2 retention patterns were sensitive to incubation temperature with tri-fold dissolution capacity at 5~?C compared to 25?C,but insensitive to variations in soil water *** resulting soil-specific relationship between p CO_2 and CO_2,aq concentration allowed the quantification of CO_2,aq concentration as a function of headspace p CO_2.

关键词： carbonate equilibrium CO2 dissolution capacity CO_2 partial pressure microbial CO2 production soil pH sterilization-CO2-injection method volume of headspace air volume of soil solution

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Verapamil and vasospastic angina： underuse in the elderly population

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Journal of Geriatric Cardiology 2017年第7期14卷 430-435页

作者： Xavier Humbert Vincent Roule Paul Milliez joachim Alexandre Department of General Medicine Medical School Caen France Department of Pharmacology CHU de Caen Caen France Normandie University UNICAEN CHU Caen Signalisation eleetrophysiologie et imagerie des lesions d'ischOmie-reperfusion myocardique Caen France Department of Cardiology CHU de Caen Caen France

The first case of Prinzmetal angina was described in 1959 by Prinzmetal, et al. Since this description, several triggering factors have been associated with vasospastic angina （VA） and included： illicit drugs such as cocaine, amphetamine or marijuana, but also bitter-orange, alcohol, butane, chemotherapy drugs, over-the-counter medication and different antibiotics. Smoking is also a major risk factor for developing VA.t21 Thus, except for smoking, many of conventional atherosclerosis risk factors do not appear to be applicable to VA.t21 However, vasospastic angina can also occur without any triggering factor.

关键词： Calcium antagonists Elderly population Prinzmetal angina Variant angina Verapamil

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Review of History and Recent Development of Organic Farming Worldwide

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Agricultural Sciences in China 2006年第3期5卷 169-178页

作者： MA Shi-ming joachim Sauerborn Institute for Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Centre for Agriculture in the Tropics ＆ Subtropics University of Hohenheim Stuttgart 70593 Germany

The history of the organic farming worldwide was reviewed in this paper. The development of the organic farming worldwide had gone through three stages, emergence, expansion, and growth. The contributors and their thoughts during the different development stages of the organic farming were briefly introduced. And the development status of the organic farming worldwide was reviewed from the aspects of land area under organic management, land area under organic management in percentage of total agricultural area, and world markets for organic products. Besides, the main existing problems for the further development of the world＇s organic farming, as well as the development status, problems and strategies of the Chinese organic farming were discussed.

关键词： organic farming organic product review of history development status

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Biosynthesis of Monoterpenoid Indole AlkaloidAjmaline Catalyzed by Novel Reductases

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Chemical Research in Chinese Universities 2006年第2期22卷 267-269页

作者： Gerald von Schumann joachim Stckigt Department of Pharmaceutical Biology Institute of Pharmacy Johannes Gutenberg University Staudinger Weg 5 D-55099 Mainz Germany

Introduction One of the major root alkaloids of the Indian medicinal plant Rauvolfia serpenlina Benth. ex Kurz is named ajmaline. The enzymatic biosynthesis of this alkaloid has been studied for a long time by our group As a result, a biosynthetic pathway has been established, in which about 10 enzymes participate, several of them belonging to the group of NADPH-dependent reductases. Started with the biosynthetic precursors tryptamine and secologanin,

关键词： Biosynthesis Alkaloid Reductase Ajmaline

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Latent HIV-1 TAR Regulates 7SK-responsive P-TEFb Target Genes and Targets Cellular Immune Responses in the Absence of Tat

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Genomics, Proteomics & Bioinformatics 2017年第5期15卷 313-323页

作者： Sebastian Eilebrecht Bernd-joachim Benecke Arndt G. Benecke CNRS UMR8246 Université Pierre et Marie Curie Paris 75005 France ACSIOMA GmbH Technologiezentrum Ruhr Bochum 44799 Germany Center for Innate Immunity and Immune Disease University of Washington School of Medicine Seattle WA 98195 USA

The transactivating response element （TAR） structure of the nascent HIV-1 transcript is critically involved in the recruitment of inactive positive transcription elongation factor b （P-TEFb） to the promoter proximal paused RNA polymerase II. The viral transactivator Tat is responsible for subsequent P-TEFb activation in order to start efficient viral transcription elongation. In the absence of the viral transactivator of transcription （Tat）, e.g., during latency or in early stages of HIV tran- scription, TAR mediates an interaction of P-TEFb with its inhibitor hexamethylene bis-aeetamide- inducible protein 1 （HEXIM1）, keeping P-TEFb in its inactive form. In this study, we address the function of HIV-1 TAR in the absence of Tat by analyzing consequences of HIV-1 TAR overexpres- sion on host cellular gene expression. An RNA chimera consisting of Epstein-Barr virus-expressed RNA 2 （EBER2） and HIV-1 TAR was developed to assure robust overexpression of TAR in HEK293 cells. The overexpression results in differential expression of more than 800 human genes. A significant proportion of these genes is involved in the suppression of cellular immune responses, including a significant set of 7SK-responsive P-TEFb target genes. Our findings identify a novel role for HIV-1 TAR in the absence of Tat, involving the interference with host cellular immune responses by targeting 7SK RNA-mediated gene expression and P-TEFb inactivation.

关键词： HIV-1 Latency TAR 7SK RNA Cellular immunity

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Assessing Possibilities and Limitations for Biomarker Analyses on Outcrop Samples:A Case Study on Carbonates of the Shibantan Member (Ediacaran Period, Dengying Formation, South China)

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Acta Geologica Sinica(English Edition) 2014年第6期88卷 1696-1704页

作者： Jan-Peter DUDA Volker THIEL joachim REITNER Martin BLUMENBERG Geoscience Centre Geobiology Group Georg-August-University GttingenGoldschmidtstr.337077 Gttingen Germany Federal Institute for Geosciences and Natural Resources (BGR) Stilleweg 2 30655 Hannover Germany

The Shibantan Member（Dengying Formation, South China） represents one of only two carbonate settings with Ediacara-type organisms and offers a rare opportunity to study the biogeochemistry of these ecosystems. To evaluate possibilities and limitations for future biomarker studies on fossil-bearing outcrop samples of the Shibantan Member, we analysed the spatial distribution of hydrocarbons in extractable organic matter（i.e. bitumen） on a millimetre scale. Our study demonstrates that the sample and most likely also other rocks from the same setting are contaminated with petroleum-derived compounds that bear the potential for erroneous interpretations in palaeo-reconstructions. The contamination was revealed by distribution patterns and amounts of extractable n-alkanes and acyclic isoprenoids. The contamination is linked to the external weathering surfaces but also to cracks within the rock, and the extent most likely depends on concentration gradients between these contamination sources. Here we show that contamination can successfully be distinguished from syngenetic signals obtained from non-extractable organic matter（i.e. kerogen） using catalytic hydropyrolysis（Hy Py）. However, we observed that decalcification is necessary to achieve sufficient yields of kerogen-bound hydrocarbons and to avoid artificial alteration of the biomarker signals due to matrix effects.

关键词： Ediacaran biomarkers contamination syngeneity slice-experiments catalytic hydropyrolysis(HyPy)

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Selected Recent Applications of Sparse Grids

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Numerical Mathematics(Theory,Methods and Applications) 2015年第1期8卷 47-77页

作者： Benjamin Peherstorfer Christoph Kowitz Dirk Pfluger Hans-joachim Bungartz Scientific Computing Group Dept.of Computer ScienceBoltzmannstr.385748 GarchingGermany Institutefor Advanced Study Technische UniversitätMünchenLichtenbergstr.2a85748 GarchingGermany Institute for Parallel and Distributed Systems University of StuttgartUni-versitätsstr.3870569 StuttgartGermany

Sparse grids have become a versatile tool for a vast range of applications reaching from interpolation and numerical quadrature to data-driven problems and uncertainty *** review four selected real-world applications of sparse grids:financial product pricing with the Black-Scholes model,interactive explo-ration of simulation data with sparse-grid-based surrogate models,analysis of simu-lation data through sparse grid data mining methods,and stability investigations of plasma turbulence simulations.

关键词： Sparse grids hierarchical decomposition adaptivity combination technique

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