检索结果-南通市图书馆

INFLUENCE OF OXYGEN CONTENT ON SUPERCONDUCTIVITY OF Bi-SYSTEM MATERIAL

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1990年第5期7卷 237-240页

作者： WANG Shunxi XIA Jianshen ZHANG Qirui chen Xianhui chen zuyao LIU Xianming JI Mingrong Department of Physics University of Science and Technology of ChinaHefei 230022 Department of Applied Chemistry University of Science and Technology of ChinaHefei 230022 Central lab.of Structure and Element Analysis University of Science and Technology of ChinaHefei 230022

The sample with nominal composition Bi_(1.8)Pb_(0.35)Sr_(2)Ca_(2)Cu_(3)O_(y) was prepared by solid state reaction *** the measurements of resistivity,***,and the analysis of X-ray diffraction and Energy Dispersive X-ray(EDX)microanalysis,we found that:(1)there is only one superconducting transition with transition temperature near 110K,its zero-resistance temperature(T_(ce))is as high as 106.5K,the diffraction pattern is similar to that of 2223 single phase(110K),but the cation ratio of Bi:Pb:Sr:Ca:Cu is near 25.8:5.74:18.43:19.53:30.50,i.e.,Bi_(2.5)Pb_(0.5)Sr_(2)Ca_(2)Cu_(3).We suppose that the 3223 phase is caused by intergrowth in the sample;(2)like the 1-2-3 phase material,the superconductivity of Bi-system is sensitive to oxygen *** suppose that different oxygen content in the same crystal structure leads to the change of electronic structure,and so to great difference in the superconductivity.

关键词： resistance phase structure

PREPARATION OF ULTRAFINE METAL PARTICLES BY COMBINED METHOD γ-RAY RADIATION—HYDROTHERMAL CRYSTALLIZATION

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 1992年第11期5卷 407-410页

作者： chen zuyao chen Bo QIAN Yitai ZHANG Manwei YANG Li FAN chenggao University of Science and Technology of China,Hefei,China Univ of Science and Technology of China Hefei China

The γ-ray radiation technique combined with hydrothermal crystallization was firstly used to prepare ultrafine metallic particles of An,Cu and Au-Cu *** size for Au in average is about 10 *** morphologies were observ... 详细信息

关键词： radiation chemistry ultrafine powder hydrothermal technique Cu Au Cu-Al alloy

THE BEHAVIOR OF 100K SUPERCONDUCTING PHASE IN Pb-doped Bi-Ca-Sr-Cu-O SYSTEM

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1989年第2期6卷 88-91页

作者： XIA Jiansheng FANG Minghu CAO Liezhao ZHANG Qirui chen Jian chen zuyao QIAN Yitai Department of Physics University of Science and Technology of ChinaHefei Department of Applied Chemistry University of Science and Technology of ChinaHefei

The ac magnetic susceptibility,the magnetoresistance R(H)and the dependence of the resistivity on temperature under different applied field were investigated in the Pb-doped Bi-Ca-Sr-Cu-O system.A superconducting phase with Tc-100K exists tn this sintered *** forms a well connecting network,and therefore the Josephson coupling between the superconducting grains is sharply improved by doping lead.

关键词： sharply connecting resistivity

Electrical Properties and Superconductivity of MSr_(2)Nd_(2-x)CexCu_(2)O_(10-δ)(M=Ta,Nb)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1992年第9期9卷 498-500页

作者： ZHU Yingjie QIAN Yitai LI Rukang WANG Shiwei chen zuyao chen Zhaojia WANG Nanling ZHOU Guien Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026 Department of Physics University of Science and Technology of ChinaHefei 230026 Laboratory of Structure And Element Analysis University of Science and Technology of ChinaHefei 230026

A new series of layered cuprate compounds MSr_(2)Nd_(2-x)Ce_(x)Cu_(2)O_(10-δ)(M=Ta,Nb)have been *** structure of the compounds is similar to that of Tl-1222.A peak in the R-T curve for the sample of TaSr_(2)Nd_(1.3)Ce_(0.7)Cu_(2)O_(10-δ) has been observed at about *** the sample of NbSr_(2)Nd_(1.45)Ce_(0.55)Cu_(2)O_(10-δ),metal-like conductivity behaviour has been *** have found superconductivity at about 13.2K in the samples of NbSr_(2)Nd_(2-x)Ce_(x)Cu_(2)O_(10-δ)(x=0.49,0.50,0.51,0.52).

关键词： behaviour Electrical

Correlation between Carrier Concentration and Superconductivity in the 123-phase System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1991年第5期8卷 259-262页

作者： HE Zhenhui XIA Jiansheng WANG Shunxi CAO Liezhao chen zuyao ZHANG Han FANG Minghu XU Zhu’an ZHANG Qirui Department of Physics and Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026 Department of Physics Beijing UniversityBeijing 100871 Department of Physics Zhejiang UniversityHangzhou 310027

Besides the structure and oxygen content,the resistance-temperature relationship,Hall carrier concentration(nH)and midpoint temperature of superconducting transition(T_(c))were measured for more than six 123-phase systems with elemental *** correlation is found between the oxygen content and T_(c),nor is between the orthorhombic structure and T_(c).Instead,an unmonotonic relationship is jound between nH and T_(c).The optimum nH for the highest T_(c) is about 3.8 *** this draws a conclusion that nH is a parameter to describe the high T_(c) superconductivity.

关键词： phase conclusion optimum

SUPERCONDUCTIVITY IN GLASSY Bi-Sr-Ca-Cu-O SYSTEM

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1989年第12期6卷 553-556页

作者： LIN Rong chen Xianhui chen zuyao QIAN Yitai XIA Jiansheng WANG Shunxi ZHANG Qirui Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026 Department of Physics University of Science and Technology of ChinaHefei 230026

To explore high Tce in Bi-Sr-Ca-Cu-O system,many different nominal compositions have been *** resistance temperature Tce as high as 105K and only one sharp 3uperconducting transition in *** measurement has been observed in the nominal composition Bi_(2)Sr_(2)Ca_(3)Cu_(4)O_(y) by using the method of crystallization from glassy Bi-Sr-Ca-Cu-O at 875°C for above 50h.

关键词： nominal conducting susceptibility

Intercalation Reaction of Bi_(2)(Sr,Nd)_(2)CuO_(y) Bi_(2)Sr_(2)(Ca,Gd)Cu_(2)O_(y) and Related Compounds With Iodine

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1991年第11期8卷 589-592页

作者： chen zuyao GU Zhengtian QIAN Yitai WANG Xiqin HUANG Yunlan FAN chenggao ZHOU Guien Departinent of Applied Chemistry University of Science and Technology of ChinaHefei 230026 Laboratory of Structure and Element Analysis University of Science and Technology of ChinaAcademia SinicaHefei 230026

With iodine vapour treatment of various single crystals of Bi-Sr-Ca-Ln(Rare earth element)-Cu-O system,the stage-1 iodine intercalation compounds of Bi_(2)(Sr,Nd)_(2)CuO_(y) (2201),Bi_(2)Sr_(2)(Ca,Gd)Cu_(2)O_(y) or Bi_(2)Sr_(2)CaCu_(2)O_(y)(2212)and Big SrCaO14 have been prepared.x-ray difraction and transmission electron microscope analysis indicate that iodine layer of thickness 3.2-3.5A is formed between two Bi_(2)-O_(2) layers.

关键词： element iodine

New 1222-Type Thallium-Indium Layered Cuprates(Tl,In)Sr_(2)(Nd,Ce)_(2)Cu_(2)O_(z) and Their Superconductivity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1993年第1期10卷 49-52页

作者： chen zuyao TANG Yongqiu Z.Z.Sheng Y.F.Li D.O.Pederson Department of Applied Chemistry University of Science and Technology of ChinaHefei 230026 Analysis and Research Center East China Institute of Chemical TechnologyShanghai 200237 Department of Physics University of ArkansasFayettevilleA R 72701USA

A new series of 1222-type thallium-indium layered cuprate compounds(Tl,In)Sr_(2)(Nd,Ce)_(2)Cu_(2)O_(z)have been successfully synthesized in the pure or nearly pure form and identified by powder x-ray diffraction *** structure of the compounds is directly related to that of Nb-1222 NbSr_(2)(Nd,Ce)_(2)Cu_(2)O_(z),with a tetragonal body-center *** lattice parameters are a=3.85Å,c=29.56Åfor(Tl_(0.7)ln_(0.3))Srz(Nd_(0.5)Ce_(0.5))_(2)Cu_(2)O_(z),and a=3.85Å,c=29.28Åfor lnSr_(2)(Nd_(0.75)Ce_(0.25))_(2)Cu_(2)O_(z).Resistance measurements showed that(T1_(1-x)In_(x))Sr_(2)(Nd_(0.75)Ce_(0.25))_(2)Cu_(2)O_(z)(x≤0.8)are superconducting with Tc(onset)=30-40K.

关键词： pure tetragonal

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

人的本质是什么——一个需要修正的哲学命题

江淮论坛 2007年第2期 10-14页

作者：陈祖耀湖北省社会科学院湖北武汉430077

学界长期以来认为:人的本质是人的社会性,并认为这是人与动物相区别的根本特性;还认为人的本质是多个的、多级的、多方面的、多层次的复杂系统。笔者认为,这样的观点和命题,是违背马克思主义哲学关于物质第一性原理和事物的本质的定义... 详细信息

学界长期以来认为:人的本质是人的社会性,并认为这是人与动物相区别的根本特性;还认为人的本质是多个的、多级的、多方面的、多层次的复杂系统。笔者认为,这样的观点和命题,是违背马克思主义哲学关于物质第一性原理和事物的本质的定义及其规定性的。在理论和实践上都是站不住脚的,必须进行修正,肃清影响,还其真谛。

关键词：人的本质修正哲学命题