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Appraisal of Surface m.dified AISI 316 L Stainless Steels by Plasm. and Solid Nitriding Techniques

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m.terials Sciences and Applications 2020年第7期11卷 462-473页

作者： R. Guardian I. Rosales-Cadena j. L. Valle-m.ta j. Pereyra-Hernández O. Ocam.o Center of Research in Engineering and Applied Science CIICAp - UAEM. Cuernavaca Mexico

AISI 316 L stainless steels type was surface m.dified by ion and solid nitriding treatm.nt. It was dem.nstrated that a surface activation pretreatm.nt in sam.les based in acid m.xture accom.anied with NH4NO3 solution inside the container, can produce an efficient nitrogen diffusion process. As com.ared with ion nitriding treatm.nt (20%N2-80%H2), the sam.les were treated with solid nitriding technique, using Fe4KCN based com.ound at the sam. tim. and tem.erature (6 h and 500°C respectively). Superficial layers with a depth of 45 μm.average were obtained with six hours treatm.nt. Hardness surface values of two surface treatm.nts present an increased value of approxim.tely three tim.s with respect to the m.trix sam.le. Wear evaluation indicated low regim.s of weight losses for both treatm.nts. Oxidative-adhesive result is to be the predom.nant operating wear m.chanism. Positive results were obtained in solid nitriding technique as com.ared with the expensive ion nitriding technique.

关键词： Surface m.dification Hardness m.chanical Properties Wear

COVID-19 m.rtality and Vaccine Coverage——Hong Kong Special Adm.nistrative Region,China,j.nuary 6,2022-m.rch 21,2022

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China CDC weekly 2022年第14期4卷 288-292页

作者： Dallas j.Sm.th Avi j.Hakim.Gabriel m.Leung Wenbo Xu WWilliam.Schluter Ryan T.Novak Barbara m.rston Bradley S.Hersh CDC COVID-19 Response International Task Force Atlanta Epidem.c Intelligence Service CDC Li Ka Shing Faculty of m.dicine University of Hong KongHong Kong Special Administrative RegionChina National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina CDC China BeijingChina

Sum.ary What is already known about this topic?COVID-19 vaccines are im.ortant tools to protect populations from.severe disease and *** is added by this report?Am.ng persons aged≥60 years in Hong Kong,49%,had received≥2 doses of a COVID-19 vaccine,and vaccination coverage declined with *** j.nuary-m.rch 2022,reported COVID-19-associated deaths rose rapidly in Hong *** these deaths,96%occurred in persons aged≥60 years;within this age group,the risk for death was 20 tim.s lower am.ng those who were fully vaccinated com.ared with those who were unvaccinated.

关键词： doses COV deaths

Three principles for preparing Al wire with high strength and high electrical conductivity

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j.urnal of m.terials Science & Technology 2019年第5期35卷 742-751页

作者： j.P.Hou R.Li Q.Wang H.Y.Yu Z.j.Zhang Q.Y.Chen H.m. X.m.Wu X.W.Li Z.F.Zhang m.terials Fatigue and Fracture Division Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China National Quality Supervision & Inspection Center of Electrical Equipm.nt Safety Perform.nce Zhejiang Huadian Equipment Testing Institute Hangzhou 310015 China Electric Power Research Institute of Liaoning Electric Power Co. Ltd. Liaoning Electric Power Co. Ltd. Shenyang 110006 China Departm.nt of m.terials Physics and Chem.stry School of Materials Science and Engineering Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University Shenyang 110819 China

The trade-off relation between the strength and the electrical conductivity has been a Iong-standing dilem.a in m.tallic m.terials. In the study, three key principles, *** grains, sharp texture and nano-scale precipitates, were presented for preparing Al wire with high strength and high electrical conductivity based on the specially designed experim.nts for breaking the m.tually exclusive relation between the strength and the electrical conductivity. The results show that the elongated grains could lead to a higher electrical conductivity in Al wire without sacrificing the strength;while, the sharp texture can efficiently strengthen the Al wire without influencing the electrical conductivity. Furtherm.re, nano-scale precipitates with proper size can sim.ltaneously im.rove the strength and electrical conductivity of Al alloy wire. Under the guidance of the above three key principles, Al wires with high strength and high conductivity were prepared.

关键词： Al wire Texture Precipitates Strength Electrical conductivity

INFLUENCE OF ZIRCONIUm.ON m.CROSTRUCTURE AND DAm.ING CAPACITY OF ZA27 ALLOY

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Acta m.tallurgica Sinica(English Letters) 1998年第3期11卷 230-234页

作者： j.C.Wang Z.m.Zhang Y.L.Lu G.S.Song G.C.Yang Northwestern Polytechnical Univ Xi'an China

To im.rove the dam.ing capacities of m.tals and alloys, the m.crostructures and dam.ing capacities of ZA27 alloy m.dified by Zr were studied, and the dam.ing capacities at room.tem.em.ure were m.asured by using cantilever beam.techniques. The experim.nt results show that Zr can refine the Al-rich prim.ry phase and im.rove the dam.ing Capacities saliently. Com.ared with the un-m.dified one, the dam.ing capacity of ZA27 alloy m.dified by 0.3wt%Zr received 90 percent increm.nt. The high dam.ing capacities are attributed prim.rily to grain ablem.nt and the increasing of phase interfaces.

关键词： ZA27 alloy dam.ing capacity m.dification m.crostructure

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我们需要什么样的民主?

国外社会科学 2007年第6期 95-98页

作者： m.罗戈日尼科夫

俄罗斯曾创造了民主法则。现在俄罗斯面临的任务是建立民主。我们长久以来生活在一个呆板的政治、经济和社会框架中。我们进行民主化的进程已经有多年，我们寻找着失去的价值观，并正在建立公民社会和市场制度，正在走进世界共同体，但... 详细信息

俄罗斯曾创造了民主法则。现在俄罗斯面临的任务是建立民主。我们长久以来生活在一个呆板的政治、经济和社会框架中。我们进行民主化的进程已经有多年，我们寻找着失去的价值观，并正在建立公民社会和市场制度，正在走进世界共同体，但在这个进程中的亮点并不多。确实，应该就此问题进行讨论，我们彼此问道：俄罗斯的模式究竟是什么？是德国式的、

关键词：民主俄罗斯伊里因政治体制政治制度

m.CROSTRUCTURE AND PROPERTIES OF CuCr25 ALLOYS WITH DIFFERENT Ni CONTENT

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Acta m.tallurgica Sinica(English Letters) 2003年第2期16卷 151-154页

作者： C.Y.Zhang Y.P.Wang Z.m.Yang B.j.Ding Y.L.Li SheyangNationalLaboratoryform.terialsScience InstituteofMetalResearchTheChineseAcademyofSciencesShenyang110016China Schoolofm.terialsScienceandEngineering Xi‘anJiaotongUniversityXi’an710049China LiaoningElectronTubeCorporation Shenyang110023China

CuCr25 alloys containing different Ni content were prepared by vacuum.induction m.lting (VIm.. The m.cro structure and properties were tested. The results show that with the increase of Ni content in CuCr25 alloys, the Cr phase changed from.developed dendrite into nodular grains and was drastically refined; the electrical conductivity significantly decrease, but still reach the level of conventional CuCr50 when the Ni content is below 0.5%. The Ni content had little influence on their breakdown strength. The first breakdown sites transferred to the boundary of Cu and Cr phase for CuCr25Ni com.ared to the Cr phase for CuCr25 without Ni.

关键词： CuCr25 contact m.terial vacuum.induction m.lting

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SiC晶须增强硼硅酸盐玻璃

硅酸盐通报 1990年第3期9卷 28-31页

作者：李杰 m. H. Lewis 山东工业陶瓷研究设计院 Warwick大学

本文描述了SiC/硼硅酸盐玻璃(Pyrex)复合材料的生产工艺、显微结构分析及力学性能测试。研究表明晶须加入到Pyrex玻璃基体中不仅显著提高了基体材料的力学性能,而且促使了玻璃基体的结晶。主要增韧机理是裂纹偏转。

关键词：碳化硅晶须增强硼硅酸盐玻璃

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何为“主权民主”?

国外社会科学 2007年第6期 98-99页

作者： m.罗戈日尼科夫

远不是所有的主权都会保证国家及其公民的发展，也不是任何民主都意味着国家的管理会顾及人民的利益。最近半年饱受争议的“主权民主”一词代表的正是俄罗斯联邦的状态。它无论如何都不能被称为是一种新的意识形态，但它指出了经过15年... 详细信息

远不是所有的主权都会保证国家及其公民的发展，也不是任何民主都意味着国家的管理会顾及人民的利益。最近半年饱受争议的“主权民主”一词代表的正是俄罗斯联邦的状态。它无论如何都不能被称为是一种新的意识形态，但它指出了经过15年政治体制改革后俄罗斯社会所形成的政治现状。

关键词：主权民主俄罗斯政治体制政治制度

使用离子束治疗法成功治疗侵入眼内的结膜鳞状上皮细胞癌

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美国医学会眼科杂志（中文版） 2006年第3期18卷 181-183页

作者： Krista m. Ram.nas R. m.x Conway Inder K. Daftari j. Brooks Crawford j.an m. O＇ Brien 张弛（译）

由于长时间的紫外线照射，结膜鳞状上皮细胞癌在世界范围内变得越来越流行。尽管如此，原发结膜鳞状上皮细胞癌侵人眼内仍然十分罕见，因此经常导致误诊。侵及眼部大且侵袭力强的病变仅通过标准的切除手术和冷冻术往往较难治愈。对于这... 详细信息

由于长时间的紫外线照射，结膜鳞状上皮细胞癌在世界范围内变得越来越流行。尽管如此，原发结膜鳞状上皮细胞癌侵人眼内仍然十分罕见，因此经常导致误诊。侵及眼部大且侵袭力强的病变仅通过标准的切除手术和冷冻术往往较难治愈。对于这种病变的治疗，大多数研究者会建议行眼球摘除术，当有证据显示病变侵及眼眶时则行眶内容物剜除术^1-4。目前的病例显示使用离子束治疗侵入眼内的结膜鳞状上皮细胞癌是眼球摘除术外的另一种选择。就我们所知，这是第一例关于使用离子束治疗侵袭性结膜鳞状上皮细胞癌的病例报道。

关键词：鳞状上皮细胞癌治疗法离子束结膜眼内侵入眼球摘除术病例报道