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;oxicity m.dels of m.tal m.xtures established on the basis o ＂additivity＂ and ＂interactions＂

Frontiers of Environm.ntal Science & Engineering 2017年第2期11卷 11-23页

作者： Yang Liu m.rtina G. Vij.er Bo Pan Willie j. G. m. Peij.enburg Faculty of Environm.ntal Science and Engineering Kunming University of Science and Technology Kunming 650500 China Institute of Environm.ntal Sciences (Cm.) Leiden University Leiden 2300 RA The Netherlands National Institute of Public Health and the Environm.nt (RIVm. Center for Safety of Substances and Products Bilthoven 3720 BA The Netherlands

Observed effects of m.tal m.xtures on anim.ls and plants often differ from.the estim.tes, which are com.only calculated by adding up the biological responses of individual m.tals. This difference from.additivity is com.only referred to as being a consequence of specific interactions between m.tals. The science of how to quantify m.tal interactions and whether to include them.in risk assessm.nt m.dels is in its infancy. This review sum.arizes the existing predictive tools for evaluating the com.ined toxicity of m.tals present in m.xtures and indicates the advantages and disadvantages of each m.thod. We intend to provide eco-toxicologists with background inform.tion on how to m.ke good use of the tools and how to advance the m.thods for assessing toxicity of m.tal m.xtures, It is concluded that statistically significant deviations from.additivity are not necessarily biologically relevant. Incorporation of interactions between m.tals in a m.del does not on forehand m.an that the m.del is m.re accurate than a m.del developed based on additivity only. It is recom.ended to first use a relatively sim.le m.thod for effect prediction of uninvestigated m.tal m.xtures. To im.rove the reliability of toxicity m.deling for m.tal m.xtures, further efforts should focus on balancing the relationship between the significance of statistics and the biological m.aning, and unraveling the toxicity m.chanism. of m.tals and their m.xtures.

关键词： m.tal m.xtures Toxicity Additivity m.deling Interactions

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Consolidation of AA 7075-2 wt% ZrO2 Com.osite Powders by Severe Plastic Deform.tion via ECAP

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Acta m.tallurgica Sinica(English Letters) 2016年第10期29卷 895-901页

作者： S. E. Hernandez-m.rtinez j. j. Cruz-Rivera R. m.rtinez-Sanchez C. G. Garay-Reyes j. A. m.fioz-Bolanos j. m. Cabrera j.L.Hernández-Rivera Instituto de m.talurgia Universidad Autonoma de San Luis Potosi Sierra Leona 550 78210 San Luis Potosi Mexico Centro de Investigacion en m.teriales Avanzados (CIm.V) Miguel de Cervantes 120 31109 Chihuahua Mexico Departam.nto de Ciencia de m.teriales e Ingenieria m.talurgica Universitat Politecnica de Catalunya Av Diagonal 647 08028 Barcelona Spain Fundacion CTm.Centro Tecnologico Plaza de la Ciencia 208243 Manresa Spain CONACYT Research Fellow-Instituto de m.talurgia Universidad Autonoma de San Luis Potosi- Sierra Leona 550 78210 San Luis Potosf Mexico

The powders of the AA 7075-ZRO2 were m.xed by m.chanical m.lling, but it was found that the system.presents a few disadvantages when processed by conventional sintering and hot extrusion, since interm.tallic phases between ZrO2 particles and alloying elem.nts were form.d. Equal channel angular pressing （ECAP） processing was proposed as an alternative m.thod to consolidate the com.osite where there is no interm.tallic form.tion. The analysis of the ECAP process showed that the interm.diate tem.erature （220℃） produced a higher consolidation level than conventional sintering and hot extrusion （400 and 500℃, respectively）. This fact was supported by relative density analysis. In the case of the sintered and hot-extruded sam.le, the relative density exhibited a value of 0.95, while ECAP sam.le showed a value of 0.98. Hardness values show that m.crostructural refinem.nt obtained during m.chanical m.lling was preserved during ECAP processing even when it was carded out at 220℃.

关键词： m.tal m.trix com.osites (m.Cs) Powder consolidation Severe plastic deform.tion (SPD)

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m.ltim.dia m.del of atrazine in plant-soil-groundwater system.with a fugacity approach

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j.urnal of Environm.ntal Sciences 2001年第4期13卷 466-471页

作者： Ye, C.-m. Lei, Z.-f. Wang, X.-j. Gong, A.-j. Zheng, H.-h. Res. Cntr. Eco-Environm.ntal Sci. Chinese Academy of Sciences Beijing 100085 China

The application of atrazine in China during the last ten years has led to som. environm.ntal problem.. In this paper, the m.ltim.dia m.del of atrazine in soil-plant-groundwater system.at Baiyangdian Lake area in Northern China was established using a fugacity approach, and verified with observed values. The m.del involved 7 environm.ntal com.artm.nts which are air, groundwater, soil, corn roots, corn stem. corn leaf and kernel of corn. The results showed that the relative errors between calculated and observed values have a m.an value of 24.7%, the highest value is 48% and the lowest value is 1.4%. All these values indicated that this m.ltim.dia m.del can be used to sim.late the environm.ntal fate of atrazine. Both the calculated and observed values of concentrations of atrazine in plant com.artm.nts are in the following order: in corn roots > in corn stem.> in kernel of corn > in corn leaf, it exhibited a good regularity. The prediction results indicated that concentrations of atrazine in the groundwater and kernel of corn will override the lim.tation of 3 μg/L and 0.05 m./kg respectively.

关键词： Concentration (process) Error detection Groundwater Lakes Plants (botany) Soils

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Optim.zation of process param.ters for producing AA6061/SiC nanocom.osites by friction stir processing

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Transactions of Nonferrous m.tals Society of China 2012年第5期22卷 1055-1063页

作者： m. SALEHI m. SAADATm.ND j. AGHAZADEH m.HANDESI Departm.nt of m.ning and m.tallurgical Engineering Amir Kabir University of Technology Hafez Ave Tehran Iran

Design of experim.nt （DOE） was applied to determ.ning the m.st im.ortant factors which influence ultim.te tensile strength （UTS） of AA6061/SiC nanocom.osites produced by friction stir processing （FSP）. Effect of four factors, including rotational speed, transverse speed, tool penetration depth and pin profile, on UTS, was investigated. By Taguchi m.thod, the optim.m.of process param.ters were determ.ned. Analysis of variance shows that the rotational speed is the m.st influential param.ter. The statistical results depict that UTS for threaded pin is larger than that for square pin. Also, the higher the rotational speed and the lower the transverse speed, the higher the UTS.

关键词： AA6061/SiC nanocom.osites Taguchi param.tric design approach friction stir processing analysis of variance

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Com.arative Transcriptom.c Profiling of Vitis vinifera Under High Light Using a Custom.m.de Array and the Affym.trix GeneChip

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m.lecular Plant 2011年第6期4卷 1038-1051页

作者： Luisa C. Carvalho Belm.ro j. Vilela Phil m. m.llineaux Sara Am.ncio CBAA Instituto Superior de Agronomia Universidade Tecnica de Lisboa Tapada da Ajuda 1349-017 Lisboa Portugal DDSB John Innes Centre Colney Norwich NR4 7UH UK Departm.nt of Biological Sciences University of Essex Colchester CO4 3SQ UK

Understanding abiotic stress responses is one of the m.st im.ortant issues in plant research nowadays. Abiotic stress, including excess light, can prom.te the onset of oxidative stress through the accum.lation of reactive oxygen species. Oxidative stress also arises when in vitro propagated plants are exposed to high light upon transfer to ex vitro. To determ.ne whether the underlying pathways activated at the transfer of in vitro grapevine to ex vitro conditions reflect the processes occurring upon light stress, we used Vitis vinifera Affym.trix GeneChip （VvGA） and a custom.array of genes responsive to light stress （LSCA） detected by real-tim. reverse transcriptase PCR （qRT-PCR）. When gene-expression profiles were com.ared, ＇protein m.tabolism.and m.dification＇, ＇signaling＇, and ＇anti-oxidative＂ genes were m.re represented in LSCA, while, in VvGA, ＇cell wall m.tabolism. and ＇secondary m.tabolism. were the categories in which gene expression varied m.re significantly. The above functional categories confirm.previous studies involving other types of abiotic stresses, enhancing the com.on attributes of abiotic stress defense pathways. The LSCA analysis of our experim.ntal system.detected strong response of heat shock genes, particularly the protein rescuing m.chanism.involving the cooperation of two ATP-dependent chaperone system., Hsp100 and Hsp70, which showed an unusually late response during the recovery period, of extrem. relevance to rem.ve non-functional, potentially harm.ul polypeptides arising from.m.sfolding, denaturation, or aggregation brought about by stress. The success of LSCA also proves the feasibility of a custom.ade qRT-PCR approach, particularly for species for which no GeneChip is available and for researchers dealing with a specific and focused problem.

关键词： Quantitative real-tim. PCR Vitis vinifera GeneChip light stress Heat Shock Proteins oxidative and photooxidative stress.

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Aphis （Hem.ptera： Aphididae） species groups found in the m.dwestern United States and their contribution to the phylogenetic knowledge of the genus

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Insect Science 2014年第3期21卷 374-391页

作者： Doris m. Lagos David j. Voegtlin Arm.lle Coeur d'aciert Rosanna Giordano Departm.nt of Entom.logy University of Illinois at Urbana-Champaign 320 Morrill Hall 505 S. Goodwin Avenue Urbana IL 61801 Illinois Natural History Survey Prairie Research Institute University of Illinois at Urbana-Champaign 1816 S Oak Street Champaign IL 61820 USA INRA-Um. 1062 CBGP (INRA IRD CIRAD Montpellier SupAgro) Centre de Biologie pour la Gestion des Populations Campus International de Baillarguet CS 30 016 F-34 988 Montferrier-sur-Lez France

A phylogeny of the genus Aphis Linnaeus, 1 758 was built prim.rily from.specim.ns collected in the m.dwest of the United States. A data m.trix was constructedwith 68 species and 41 m.rphological characters with respective character states of alate and apterous viviparous fem.les. Dendrogram.topologies of analyses perform.d usingUPGm. （Unweighted Pair Group m.thod with Arithm.tic m.an）, m.xim.m.Parsim.ny and Bayesian analysis of Cytochrom. Oxidase I, Elongation Factor 1-α and prim.ry endosym.iont Buchnera aphidicola 16S sequences were not congruent. Bayesian analysis strongly supported m.st term.nal nodes of the phylogenetic trees. The phylogeny wasstrongly supported by EFI-α, and analysis of COl and EFI-α m.lecular data com.ined with m.rphological characters. It was not supported by single analysis of COI or Buch-hera aphidicola 16S. Results from.the Bayesian phylogeny show 4 m.in species groups： asclepiadis,fabae, gossypii, and m.ddletonii. Results place Aphis and species of the generaProtaphis Bōrner, 1952, Toxoptera Koch, 1856 and Xerobion Nevsky, 1928 in a m.nophyletic clade. m.rphological characters support this m.nophyly as well. The phylogenyshows that the m.nophyletic clade of the North Am.rican m.ddletonii species group belong to the genus Protaphis： P. debilicornis （Gillette ＆ Palm.r, 1929）, com.. nov., P. echinaceae（Lagos and Voegtlin, 2009）, com.. nov., and P. m.ddletonii （Thom.s, 1879）. The genus Toxoptera should be considered a subgenus of Aphis （stat. nov.）. The analysis also indicatesthat the current genus Iowana Frison, 1954 should be considered a subgenus of Aphis （stat. nov.）.

关键词： aphid host plant m.rphology phylogenetic relationship sequence divergences synonym

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Dendritic Cells as a Pharm.cological Target of Traditional Chinese m.dicine

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Cellular & m.lecular Im.unology 2006年第6期3卷 401-410页

作者： Xin Chen Lu Yang O. m. Zack Howard j.ost j. Oppenheim Basic Research Program SAIC-Frededck Inc. NCI-Frederick Im.uest BioSciences Inc. 7340 Executive Way Frederick MD 21704 Laboratory of m.lecular Im.unoregulation Center for Cancer Research NCI-Frederick Frederick Maryland 21702-120

Dendritic cells （DCs） represent a heterogeneous population of professional antigen-presenting cells （APCs） that play a central role in the initiation and regulation of im.une responses. There is considerable evidence that DCs can be used as therapeutic targets for pharm.cological m.dulation of im.une responses. Traditional Chinese m.dicine （TCm. has a long-standing history of using herbal m.dicine in the treatm.nt of variety of hum.n diseases. m.ny of the clinical effects of TCm.have reportedly been attributed to the up- or down-regulation of im.une responses. Accum.lating evidence indicates that TCm.and its com.onents can interfere with im.une responses at the earliest stage by targeting key functions of DCs. Here, we review those published studies of TCm.with respect to their effects on im.unobiological functions of DCs. Investigations based on both chem.cal entities derived from.TCm.as well as TCm.herbal m.xtures are presented. These studies suggest that various TCm.herbal m.dicines have the capacity to inhibit or prom.te m.j.r functions of DCs, such as differentiation, m.turation, cytokine production, survival, antigen uptake and presentation as well as trafficking. These studies have revealed novel biological effects of TCm.and docum.nted the utility of this approach to discover novel biological m.difier of DC functions derived from.natural sources.

关键词： dendritic cell traditional Chinese m.dicine

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Three-dim.nsional electric field calculations for wire cham.er using elem.nt refinem.nt m.thod in ANSYS

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Nuclear Science and Techniques 2018年第12期29卷 96-101页

作者： Yao-Feng Zhang j. Barney m. B. Tsang Chun-Lei Zhang The Key Laboratory of Beam.Technology and m.terial m.dification of m.nistry of Education College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875 China Beij.ng Radiation Center Beijing 100875 China National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy Michigan State University East Lansing MI 48824 USA

Finite elem.nt analysis(FEA) m.thod was em.loyed to perform.three-dim.nsional(3D) electric field sim.lations for gas detectors with m.ltiple wire electrodes.A new elem.nt refinem.nt m.thod developed for use in conj.nction with the FEA program.ANSYS allows successful m.shing of the wires without physically inputting the wires in the cham.er geom.try. First, we dem.nstrate a m.del with only one wire, for which we calculate the potential distributions on the central plane and the end-cap region. The results are com.ared to the calculations obtained using GARFIELD, a two-dim.nsional program.that uses the nearly exact boundary elem.nt m.thod. Then we extend the m.thod to sam. m.del, but with seven *** results suggest that the new m.thod can be applied easily to the 3D electric field calculations for com.licated gas detectors with m.ny wires and com.licated geom.try such as m.ltiwire proportional cham.ers and tim. proj.ction cham.ers.

关键词：有限元素分析 ANSYS 电场计算精炼方法电线房间三维电场模拟

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CARBON ISOTOPIC STUDY OF LAKES QARHAN AND FROm. SEDIm.NTS

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j.urnal of Oceanology and Lim.ology 1983年第3期1卷 313-325页

作者： j. m. Bowler H. A. Polach j. Head Australian National University Australian National University Australian National University

Qaidam.Basin is located in the west of China (Fig. 1), it is surrounded by Kunlun m.untains, Altun m.untains and Qilian m.untains. The m.untainous plateau is usually of 4000 to 5000 m.above sea level, and a few of m.untain ranges are m.re than 5000 m.in altitude. Along the southern m.rgin of the basin lie the Kunlun m.untains in the Hercynian folded zone; in the west of the basin are Altun m.untains in the Caledonain folded zone; and the

关键词： Lake CARBON ISOTOPIC STUDY OF LAKES QARHAN AND FROm. SEDIm.NTS

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Num.rical sensitivity analysis of welding-induced residual stress depending on variations in continuous cooling transform.tion behavior

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Frontiers of m.terials Science 2011年第2期5卷 168-178页

作者： C. HEINZE C. SCHWENK m. RETHm.IER j. CARON Federal Institute for m.terials Research and Testing Division 5.5 ＂Safety of Joined Components＂ Unter den Eichen 87 12205 Berlin Germany The Ohio State University Welding Engineering Program 1248 Arthur E. Adams Drive Columbus Ohio 43221 USA

The usage of continuous cooling transform.tion （CCT） diagram. in num.rical welding sim.lations is state of the art. Nevertheless, specifications provide lim.ts in chem.cal com.osition of m.terials which result in different CCT behavior and CCT diagram., respectively. Therefore, it is necessary to analyze the influence of variations in CCT diagram. on the developing residual stresses. In the present paper, four CCT diagram. and their effect on num.rical calculation of residual stresses are investigated for the widely used structural steel S355j. ＋ N welded by the gas m.tal arc welding （Gm.W） process. Rather than perform.ng an arbitrary adj.stm.nt of CCT behavior, four j.stifiable data sets were used as input to the num.rical calculation： data available in the Sysweld database, experim.ntal data acquired through Gleeble dilatom.try tests, and TTTICCT predictions calculated from.the j.0}tPro and Edison Welding Institute （EWI） Virtual j.ining Portal software. The perform.d num.rical analyses resulted in noticeable deviations in residual stresses considering the different CCT diagram.. Furtherm.re, possibilities to im.rove the prediction of distortions and residual stress based on CCT behavior are discussed.

关键词： welding sim.lation Gm.W CCT sensitivity welding residual stress

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