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Investigation of the phase space in lead‐free(K_(x)Na_(1-x))_(1-y)Li_(y)(Nb_(1-z)Ta_(z))O_(3) ferroelectric ceramics

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Journal of Advanced Ceramics 2015年第4期4卷 282-291页

作者： Henry E.MGBEMERE rolf JANSSEN Gerold A.SCHNEIDER Department of Metallurgical&Materials Engineering University of LagosAkokaLagosNigeria Institute of Advanced Ceramics Hamburg University of TechnologyDenickestrasse 1521073 HamburgGermany

A library of ceramic compounds based on the lead-free(K_(x)Na_(1-x))1-yLiy(Nb1-zTaz)O_(3)solid solution has been synthesized and characterized using high-throughput experimentation(HTE)*** phase space previously reported by Saito and Takao has been expanded to{{x,0.1,1.0},{y,0,0.1},{z,0,0.2}},and new phase boundaries are *** relative density values show that with the appropriate sintering temperature,~92%of the theoretical density can be *** relative permittivity values show that with increasing amount of K+and Ta5+,the dielectric constant values *** effect of density on the dielectric constant values is however *** values ranging from 109 to 1013Ω·cm are obtained for the *** piezoelectric charge coefficient values for selected compositions show that higher values are obtained close to the phase boundaries rather than away from *** properties for the ceramic library using the HTE method are generally 15%-20%less than from the conventional *** method is therefore more suited for screening of sample compositions than for producing samples with high piezoelectric properties.

关键词： ferroelectrics high-throughput synthesis (K_(x)Na_(1-x))NbO_(3)(KNN) lead-free ceramics

Hydro-pyrolysis of lignocellulosic biomass over alumina supported Platinum, Mo2C and WC catalysts

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 155-161页

作者： Songbo He Jeffrey Boom rolf van der Gaast K. Seshan Catalytic Processes and Materials Faculty of Science & Technology University of Twente 7500 AE Enschede The Netherlands

In-line hydro-treatment of bio-oil vapor from fast pyrolysis of lignocellulosic biomass （hydro-pyrolysis of biomass） is studied as a method of upgrading the liquefied bio-oil for a possible precursor to green fuels. The nobel metal （Pt） and non-noble metal catalysts （Mo2C and WC） were compared at 500 ℃ and atmospheric pressure which are same as the reaction conditions for fast pyrolysis of biomass. Results indicated that under the pyrolysis conditions, the major components, such as acids and carbonyls, of the fast pyrolysis bio-oil can be completely and partially hydrogenated to form hydrocarbons, an ideal fossil fuel blend, in the hydro-treated bio-oil. The carbide catalysts perform equally well as the Pt catalyst regarding to the aliphatic and aromatic hydrocarbon formation （ca. 60%）, showing the feasibility of using the cheap non-noble catalysts for hydro-pyrolysis of biomass.

关键词： bio-oil pyrolysis hydro-deoxygenation (HDO) non-noble metal catalysts hydro-treatment

Approximation Algorithms for 3D Orthogonal Knapsack

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Journal of Computer Science & Technology 2008年第5期23卷 749-762页

作者： Florian Diedrich rolf Harren Klaus Jansen Ralf Thle Henning Thomas Institute of Computer Science University of Kiel Max-Planck-Institut für Informatik Campus E1466123 Saarbrücken Germany Department of Computer Science ETH ZurichZurich Switzerland

We study non-overlapping axis-parallel packings of 3D boxes with profits into a dedicated bigger box where rotation is either forbidden or permitted, and we wish to maximize the total profit. Since this optimization problem is NP-hard, we focus on approximation algorithms. We obtain fast and simple algorithms for the non-rotational scenario with approximation ratios 9 ＋ ε and 8 ＋ ε, as well as an algorithm with approximation ratio 7 ＋ ε that uses more sophisticated techniques; these are the smallest approximation ratios known for this problem. Furthermore, we show how the used techniques can be adapted to the case where rotation by 90° either around the z-axis or around all axes is permitted, where we obtain algorithms with approximation ratios 6 ＋ ε and 5 ＋ ε, respectively. Finally our methods yield a 3D generalization of a packability criterion and a strip packing algorithm with absolute approximation ratio 29/4, improving the previously best known result of 45/4.

关键词： approximation algorithm computational and structural complexity geometric configurations

Transport and fate of mercury under different hydrologic regimes in polluted stream in mining area

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Journal of Environmental Sciences 2011年第5期23卷 757-764页

作者： Yan Lin Thorjorn Larssen rolf D. Vogt Xinbin Feng Hua Zhang Department of Chemistry University of Oslo POB 1033 0315 Oslo Norway. E-mail:yan.lin@kjemi.uio.no Norwegian Institute for Water Research Gaustadalleen 21 0349 Oslo Norway State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Seepage from Hg mine wastes and calcines contains high concentrations of mercury （Hg）. Hg pollution is a major environmental problem in areas with abandoned mercury mines and retorting units. This study evaluates factors, especially the hydrological and sedimentary variables, governing temporal and spatial variation in levels and state of mercury in streams impacted by Hg contaminated runoff. Samples were taken during different flow regimes in the Wanshan Hg mining area in Guizhou Province, China. In its headwaters the sampled streams/rivers pass by several mine wastes and calcines with high concentration of Hg. Seepage causes serious Hg contamination to the downstream area. Concentrations of Hg in water samples showed significant seasonal variations. Periods of higher flow showed high concentrations of total Hg （THg） in water due to more particles being re-suspended and transported. The concentrations of major anions （e.g., Cl-, F-, NO3- and SO4^2-） were lower during higher flow due to dilution. Due to both sedimentation of particles and dilution from tributaries the concentration of THg decreased from 2100 ng/L to background levels （〈 50 ng/L） within 10 km distance downstream. Sedimentation is the main reason for the fast decrease of the concentration, it accounts for 69% and 60% for higher flow and lower flow regimes respectively in the upper part of the stream. Speciation calculation of the dissolved Hg fraction （DHg）（using Visual MINTEQ） showed that Hg（OH）2 associated with dissolved organic matter is the main form of Hg in dissolved phase in surface waters in Wanshan （over 95%）.

关键词： mercury hydrology temporal variation fractionation and speciation

Selected gas response measurements using reduced graphene oxide decorated with nickel nanoparticles

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Nano Materials Science 2021年第4期3卷 412-419页

作者： Ilka Simon Yulyan Haiduk rolf Mtilhaupt Vladimir Pankov Christoph Janiak Institut für Anoganische Chemie und Strukturchemie Heinrich-Heine Universität Düsseldorf 40204DüsseldorfGermany Chemical Faculty Belarusian State UniversityLenningradskaya Str.14220050 MinskBelarus Freiburg Materials Research Center and Institute for Macromolecular Chemistry Albert-Ludwigs-UniversityFreiburg79104FreiburgGermany

The work reports the synthesis of nickel nanoparticles supported on thermally reduced graphene oxides(rGO)in the ionic liquid[BMIm][NTf_(2)]through microwave decomposition ***@rGO with the polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)as binder was positively tested for its response towards the oxidizing gas nitrogen dioxide(10 ppm in air),the reducing gas carbon monoxide(3000 ppm in N_(2))and the volatile organic compound(VOC)acetone(35,000 ppm in air).The results from different gases were compared at different temperatures with the best results for NO_(2) at 200℃.Additionally,it is shown for NO_(2) gas that the Ni@rGO-PEDOT:PSS polymer composite gives better results than the rGO-PEDOT:PSS polymer *** the heat treatment the oxidation state of pure nickel nanoparticles were confirmed by powder diffraction.

关键词： Nickel nanoparticles Reduced graphene oxide Gas sensing Nanocomposite

Herbal hepatotoxicity:Challenges and pitfalls of causality assessment methods

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World Journal of Gastroenterology 2013年第19期19卷 2864-2882页

作者： rolf Teschke Christian Frenzel Johannes Schulze Axel Eickhoff Division of Gastroenterology and Hepatology Department of Internal Medicine ⅡKlinikum HanauD-63450 HanauGermany Academic Teaching Hospital of the Medical Faculty Johann Wolfgang Goethe-Universit t Frankfurt am MainD-60590 Frankfurt am MainGermany Department of Medicine Ⅰ University Medical Center Hamburg EppendorfD-20246 HamburgGermany nstitute of Industrial Environmental and Social MedicineMedical FacultyJohann Wolfgang GoetheUniversitat Frankfurt am MainD-60590 Frankfurt am MainGermany

The diagnosis of herbal hepatotoxicity or herb induced liver injury(HILI) represents a particular clinical and regulatory challenge with major pitfalls for the causality *** the day HILI is suspected in a patient,physicians should start assessing the quality of the used herbal product,optimizing the clinical data for completeness,and applying the Council for International Organizations of Medical Sciences(CIOMS) scale for initial causality *** scale is structured,quantitative,liver specific,and validated for hepatotoxicity *** items provide individual scores,which together yield causality levels of highly probable,probable,possible,unlikely,and *** completion by additional information including raw data,this scale with all items should be reported to regulatory agencies and manufacturers for further *** CIOMS scale is preferred as tool for assessing causality in hepatotoxicity cases,compared to numerous other causality assessment methods,which are inferior on various *** these disputed methods are the Maria and Victorino scale,an insufficiently qualified,shortened version of the CIOMS scale,as well as various liver unspecific methods such as thead hoc causality approach,the Naranjo scale,the World Health Organization(WHO) method,and the Karch and Lasagna *** expert panel is required for the Drug Induced Liver Injury Network method,the WHO method,and other approaches based on expert opinion,which provide retrospective analyses with a long delay and thereby prevent a timely assessment of the illness in question by the *** conclusion,HILI causality assessment is challenging and is best achieved by the liver specific CIOMS scale,avoiding pitfalls commonly observed with other approaches.

关键词： Herbal hepatotoxicity Herb induced liver injury Herbs Drug hepatotoxicity Drug induced liver injury Causality assessment

THE GROWTH OF SINGLE CRYSTAL AND THE DETERMINATION OF CRYSTALLOGRAPHIC PA RAMETERS OF （L-TRYPTOPHAN）A1-INSULIN AND （D-TRYPTOPHAN）A1-INSULIN

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Science China Chemistry 1985年第11期28卷 1157-1162页

作者：万柱礼,梁栋材,rolf GEIGER Institute of Biophysics Academia Sinica Beijing Institute of Biophysics Academia Sinica Beijing HOEOHST-Aktiengesellschaft: D-6230 Frankfurt (Main)

The crystal-growing conditions and the results of preliminary X-ray crystallographic analysis of （L-Try）A1-insulin and （D-Try）A1-insulin are reported. The single crystals of this pair of insulin analogue suitable for X-ray diffraction analysis have been grown in the citrate buffer system by still-setting method. They both belong to the trigonal system with space group R3. The parameters of the unit cell （L-Trp）A1-insulin are αH= 80.31, cH= 37.45 and those of （D-Trp）A1-insulin αH = 79.48, cH = 43.81. There are two molecules in an asymmetric unit. The obtained results are discussed.

关键词： D-TRYPTOPHAN INSULIN INSULIN AND L-TRYPTOPHAN THE GROWTH OF SINGLE CRYSTAL AND THE DETERMINATION OF CRYSTALLOGRAPHIC PA RAMETERS OF A1

Dissolved organic sulfur in streams draining forested catchments in southern China

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Journal of Environmental Sciences 2012年第4期24卷 704-710页

作者： Zhanyi Wang Xiaoshan Zhang Zhangwei Wang Yi Zhang Bingwen Li rolf Vogt Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China College of Ecology and Environmental Science Inner Mongolia Agricultural UniversityHohhot 010018China Department of Chemistry University of OsloP.O.BOX 1033BlindernN-0315 OsloNorway

Dissolved organic sulfur （DOS） is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. Dissolved sulfur was fractionated into dissolved organic sulfur （DOS） and inorganic sulfate （SO]-） for 95 stream water samples. The results showed that the concentration of DOS ranged from 0 to 13.1 mg/L （average 1,3 mg/L） in all the streams, High concentrations of DOS in stream waters were found in the sites with high concentrations of sulfate. DOS constituted less than 60.1% of dissolved sulfur （average 17.9%）. Statistical analysis showed that DOS concentration was correlated with SO42- in streams waters and total sulfur in surface layer soils. The results also showed that DOS concentration in stream waters had a seasonal variation, but no trends were found with it. The implication was that the long term sulfur deposition had led the increase of the concentration and fraction of DOS in stream waters in acid rain prevailing regions

关键词： dissolved organic sulfur stream water Chinese forests sulfur deposition

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马克思恩格斯与法文版《资本论》

现代哲学 2024年第2期 9-18页

作者： [德]罗尔夫·黑克尔 [法]让-努玛·迪康热程雨凡(译) 张凤凤(校) 柏林MEGA编辑促进会法国鲁昂大学历史系法国《马恩大典》编委会中央党史和文献研究院第五研究部北京100032 北京大学哲学系北京100871

在马克思诞辰200周年之际,法国出版了3种著作,其中收录了新发现的马克思恩格斯与法文版《资本论》出版商拉沙特尔之间的通信、法文版《资本论》的出版合同以及其他一些书信和文献。本文以这批新文献为基础介绍了出版合同的主要内容,法... 详细信息

在马克思诞辰200周年之际,法国出版了3种著作,其中收录了新发现的马克思恩格斯与法文版《资本论》出版商拉沙特尔之间的通信、法文版《资本论》的出版合同以及其他一些书信和文献。本文以这批新文献为基础介绍了出版合同的主要内容,法文版《资本论》的装帧、出版形式、出版经过和参与人员等。本文还根据新发现的书信还原了刊印马克思肖像和亲笔信的经过,对MEGA~2第II部分第7卷中给出的相关信息做了进一步补充,尤其是排印和审读过程中遇到的困难和一些重要的时间点。文章最后还介绍了这批珍贵文献的来源和其中一些书信的去向。

关键词：马克思恩格斯法文版《资本论》书信

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