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journal of Rare Earths 2019年第1期37卷 88-94,M0005页

作者： jinghua jiang Qiuyuan Xie Mingshan Qiang Aibin Ma evans-Kwesi Taylor Yuhua Li Dan Song jianqing Chen College of Mechanics and Materials Hohai University Suqian Institute Hohai University

A commercial as-cast ME21 magnesium alloy containing rare-earth (RE) element was processed by equalchannel angular pressing to obtain fine-grained micro structure. Stress corrosion cracking (SCC) behaviors of the fine-grained samples were studied by slow-strain-rate testing in air, distilled water and Hanks’solution at the strain rate of 1×10^(-6) s^(-1). All samples show a relatively low SCC sensitivity in distilled water but a great SCC tendency in Hanks’ solution. The microscopic observations of the fracture surfaces and the side surfaces reveal obvious active anodic dissolution and hydrogen embrittlement cracks, which indicate the higher SCC susceptibility in Hanks'solution. The fine-grained microstructure with more crystal defects promotes the passivation process of the oxide film and restrains the hydrogen induced cracking of the ME21 magnesium alloy, leading to the higher general corrosion resistance as well as SCC resistance.

关键词： Magnesium alloy Stress corrosion cracking Equal-channel angular pressing Corrosion medium Fine-grained Rare earths

The Voisey's Bay Ni-Cu-Co Sulfide Deposit, Labrador, Canada: Emplacement of Silicate and Sulfide-Laden Magmas into Spaces Created within a Structural Corridor

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西北地质 2012年第4期45卷 17-38页

作者： Peter C.Lightfoot Dawn evans-Lamswood Robert Wheeler Vale ExplorationHighway 17 WestSudburyOntarioP0M 1N0Canada Vale Newfoundland and Labrador Limited Bally Rou Place280Torbay RoadSuite W200St.John'sNewfoundlandA1A 3W8Canada

The Voisey's Bay Ni-Cu-Co sulfide deposit is hosted in a 1.34 Ga mafic intrusion that is part of the Nain Plutonic Suite in Labrador, *** Ni-Cu-Co sulfide mineralization is associated with magmatic breccias that are typically contained in weakly mineralized olivine gabbros, troctolites and ferrogabbros, but also occur as veins in adjacent *** mineralization is associated with a dyke-like body which is termed the feeder *** dyke connects the shallow differentiated Eastern Deeps chamber in the east to a deeper intrusion in the west termed the Western Deeps *** the conduit is connected to the Eastern Deeps Intrusion, the Eastern Deeps Deposit is developed at the entry line of the dyke along the steep north wall of the Eastern Deeps *** Eastern Deeps Deposit is surrounded by a halo of moderately to weakly mineralized Variable-Textured Troctolite (VTT) that reaches a maximum thickness above the ENE-WSW axis of the Eastern Deeps Deposit. At depth to the west, the conduit is adjacent to the south side of the Western Deeps Intrusion, where the dyke and intrusion contain disseminated magmatic sulfide *** Reid Brook Zone plunges to the east within the dyke, and both the dyke and adjacent paragneiss are *** Ovoid Deposit comprises a bowl-shaped body of massive sulfide where the dyke widens near to the present-day *** is not clear whether this deposit was developed as a widened-zone within the conduit or at the entry point into a chamber that is now lost to erosion. The massive sulfides and breccia sulfides of the Eastern Deeps are petrologically and chemically different when compared to the disseminated sulfides in the VTT; there is a marked break in Ni tenor (Ni content in 100% sulfide, abbreviated to [Ni]100) and Ni/Co of sulfide between the *** boundary of the sulfide types is often marked by strong sub-horizontal alignment of heavily digested and metamorphosed paragneiss fragments, developm

关键词： Voisey’s Bay Ni-Cu-Co sulfide deposit Labrador Canada

Divergent Nanotube Synthesis through Reversible Macrocycle Assembly

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Accounts of Materials Research 2022年第9期3卷 935-947页

作者： Michael j.Strauss Austin M.evans Emily K.Roesner Richard j.Monsky Madison I.Bardot William R.Dichtel Department of Chemistry Northwestern UniversityEvanstonIllinois 60208United States

CONSPECTUS:Nanotubes offer a unique combination of structural precision,tunable interior environments,and high aspect ratios that will be useful for many *** these desirable attributes,widespread explorations into the properties and applications of chemically designed nanotubes have been limited by challenges related to their *** realization has motivated developing a unified synthetic nanotube design,which would enable wide-reaching explorations into one-dimensional molecular architectures.

关键词： realization cycle interior

有机阴离子柱撑水滑石的插层组装及超分子结构

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过程工程学报 2002年第4期2卷 355-360页

作者：李殿卿冯桃 evans D G 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

以水滑石Mg4Al2(OH)12CO3.4H2O为前体,采用离子交换法进行插层组装制备了丁二酸、己二酸、十二烷基磺酸、对羟基苯甲酸、苯甲酸和对苯二甲酸柱撑水滑石,并用XRD, FTIR和DTA测试技术对样品进行了表征. 结果表明,通过控制离子交换条件,6... 详细信息

以水滑石Mg4Al2(OH)12CO3.4H2O为前体,采用离子交换法进行插层组装制备了丁二酸、己二酸、十二烷基磺酸、对羟基苯甲酸、苯甲酸和对苯二甲酸柱撑水滑石,并用XRD, FTIR和DTA测试技术对样品进行了表征. 结果表明,通过控制离子交换条件,6种有机酸根离子可以插入水滑石的层间完全取代CO32离子,并形成具有超分子结构的稳定有机阴离子柱撑水滑石.

关键词：层状前体柱撑水滑石离子交换插层组装超分子结构

An Application of the Inverse Solution for Electric Current Distribution From Magnetic Field Measurements in Aluminium Electrolysis Cells

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journal of Iron and Steel Research International 2012年第S1期19卷 561-565页

作者： Valdis Bojarevics james W.evans University of Greenwich Park Row London SE10 9LSUK Dept.Matls.Sci.& Eng. University of California Berkeley and Wireless Industrial TechnologiesInc.

A mathematical theory and the software application based on the full MHD model of the electrolysis cell is used to predict the electric current distribution over the anodes from the measurement of magnetic fields at specifically defined node points assumed to be available from the wireless *** full 3d busbar configuration of two different commercial ceils are used for the model *** is demonstrated that a unique solution for the electric current can be obtained when two sensors per each anode are used to detect the single component of magnetic *** mathematical software is tested for the sensitivity to the busbar configuration *** ability to monitor continuously the electric current distribution to high accuracy helps to control disturbances and deviations from a normal production process.

关键词： aluminium electrolysis cell inverse electromagnetic problem electric current network magnetic field

草甘膦插层镁铝水滑石MgAl-LDH-gly的释放性能研究

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高等学校化学学报 2004年第10期25卷 1869-1874页

作者：张娴张慧卫敏 D.G.evans 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

采用成核 /晶化隔离法将草甘膦 ( Glyphosate:gly)插层组装到镁铝水滑石层间 ,制得草甘膦插层镁铝水滑石 ( Mg Al-LDH-gly) .在水和碳酸钠溶液中考察了 gly的释放性能 ,初步探讨了 Mg Al-LDH-gly在这两种溶液中的释放机理 ,认为其释放... 详细信息

采用成核 /晶化隔离法将草甘膦 ( Glyphosate:gly)插层组装到镁铝水滑石层间 ,制得草甘膦插层镁铝水滑石 ( Mg Al-LDH-gly) .在水和碳酸钠溶液中考察了 gly的释放性能 ,初步探讨了 Mg Al-LDH-gly在这两种溶液中的释放机理 ,认为其释放机理主要为离子交换 ,释放速率较大的初期符合一级动力学过程 .用磷酸缓冲溶液考察环境 p H值对 Mg Al-LDH-gly释放的影响 ,证明弱碱性 ( p H=7.6)和偏中性 ( p H=6.6)环境有利于其释放 ;探讨混合无机阴离子溶液中无机阴离子对 Mg Al-LDH-gly释放性能的影响 ,结果表明 ,Mg

关键词：草甘膦插层组装镁铝水滑石释放性能成核/晶化隔离法离子交换除草剂

Flash MX、Dreamweaver MX、Fireworks MX、FreeHand MX四合一宝典

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Modeling of Defect Production in Helium-implanted Silicon Carbide Crystal—an explanation of our TEM results

丛书名：美国计算机“宝典”丛书

2003年

作者：（美）joyce j.evans等王勇等译

全书介绍了Flash MX，Dreamweaver MX，Fireworks MX和FreeHand MX四个软件。通过贯穿全书的一个构建Habitat Alert网站的具体实例了解整个流程的每一具体步骤。

ISBN: (纸本)7505390139

全书介绍了Flash MX，Dreamweaver MX，Fireworks MX和FreeHand MX四个软件。通过贯穿全书的一个构建Habitat Alert网站的具体实例了解整个流程的每一具体步骤。

关键词：制作图形软件网页软件工具动画

来源：畅想之星图书光盘版（南... 评论

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IMP & HIRFL Annual Report 2002年 56-58页

作者： S.E.Donnelly,j.H.evans joule Physics Laboratory School of Sciences University of Salford Greater Manchester M5 4WT UK. 27 Clevelands Abingdon Oxon UK.

In this work we present a model in an effort to give an explanation of the observed cross-sectional features described as follows of the bubble layer of the intermediate dose regime (Fig.1) in our recent TEM study of helium-implanted 4H-SiC.1. Sharp boundaries of the bubble layer-helium bubbles were formed in a well-defined depth region, which

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A Microwave-Irradiated StreptococcusagalactiaeVaccine Provides Partial Protection against Experimental Challenge in Nile Tilapia, Oreochromisniloticus

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World journal of Vaccines 2014年第4期4卷 184-189页

作者： David j. Pasnik joyce j. evans Phillip H. Klesius Aquatic Animal Health Research Laboratory United States Department of Agriculture Agricultural Research Service USA Warm Water Aquaculture Research Unit United States Department of Agriculture Agricultural Research Service Stoneville USA

Microwave irradiation, as opposed to formalin exposure, has not routinely been used in the preparation of killed vaccines despite the advantages of decreased chemical toxicity, ability to kill cells quickly, ease of completion requiring only a standard microwave, and potential increased protein conservation during irradiation. We evaluated the potential of microwave irradiation versus formalin fixation of bacteria to improve Streptococcus agalactiae vaccine efficacy in 5 gr fish by intraperitoneal (IP) injection and bath immersion (BI). There was no significant difference in the cumulative percent mortality (CPM) post-challenge between fish administered microwave-killed cells (MKC) or formalin killed cells (FKC) within the BI (p S. agalactiae antibody activity. Thirty days after vaccination and just prior to challenge, the optical density (OD) levels of the FKC and MKC groups in the IP trials were significantly higher (p < 0.0001) than that of the TSB group. None of the groups in the BI trial exhibited significantly different OD levels post vaccination. Fourteen days after the challenge, the OD levels of all groups in both trials increased significantly above their pre-challenge levels. Both the FKC and MKC IP groups (p < 0.0001) and only the FKC BI group (p < 0.0351) had significantly increased OD level above that of the corresponding post-challenge TSB group. These results indicate that the FKC vaccine provides marginally greater protection and increased antibody concentrations than the MKC vaccine by BI and the MKC vaccine may become a non-chemical alternative to FKC in vaccination.

关键词： Vaccine Streptococcus agalactiae Microwave

Ti-MCM-41催化剂的表面性质及介质极性对苯羟化反应化学选择性的影响

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催化学报 2001年第5期22卷 475-478页

作者：马辉何静 David G evans 段雪北京化工大学可控化学反应教育部重点实验室北京100029

用不同的铝源改性Ti MCM 41催化剂 ,得到了具有长程有序结构、n(Si) /n(Ti) =2 5的不同Si/Al比的改性Ti MCM 41.通过研究芳烃羟化反应随催化剂表面性质的变化规律发现 ,调变催化剂的表面性质 ,可控制反应物苯及目的产物苯酚与Al Ti MCM... 详细信息

用不同的铝源改性Ti MCM 41催化剂 ,得到了具有长程有序结构、n(Si) /n(Ti) =2 5的不同Si/Al比的改性Ti MCM 41.通过研究芳烃羟化反应随催化剂表面性质的变化规律发现 ,调变催化剂的表面性质 ,可控制反应物苯及目的产物苯酚与Al Ti MCM 41催化活性中心接近的程度 ,从而可实现对芳烃羟化反应化学选择性的控制 .介质极性对芳烃的化学亲和选择性也有影响。

关键词： MCM-41沸石表面性质介质极性苯羟化反应催化剂催化性能化学选择性