SUPERCONDUCTIVITY OF 2212 PHASE IN BIBASED HIGH-TC SUPERCONDUCTORS

In the Bi-based high-T(c) superconductors, three superconducting transition points were observed above the liquid-N2 temperature range. Allotropes of the 2212 phase were found. These allotropes were metastable and can interchange with the 2212 phase, and their T(c)'s vary from approximately 85 to approximately 100 K.

掺W对Bi系中高Tc超导相的影响

自Maeda发现高Tc超导体BiSrCaCuO以来,引起了人们广泛兴趣;由于它有较高的超导转变温度(Tc>100K),无剧毒、价廉和自高温冷却到室温无结构相变等特点,Bi系是一很有实用前景的高Tc超导体;已经确定Bi系中含有三个超导相(2201,2212,2223相),但是迄今要制得较纯的2223高Tc相还有一定困难,无疑这对它的基础研究和实用开发都受到了限制,因此制备更纯的Bi系2223相具有重要的意义。

YP_5O_(14):Er~(3+),Tm~(3+)晶体的合成

研究了水热法合成晶体,浓度配比、生长温度对晶体生长习性的影响.合成了一系列化学计量比的Y_(1-x-0.3)Er_(0.3)Tm_xP_5O_(14)(x=0.01～0.1)晶体,观察和分析了晶体的缺陷及成因,测定和讨论了晶体结构.

~(99)Tc~m-明胶的制备和生物分布

为考察明胶静脉注射后在机体内的吸收及分布情况,用~(99)Tc~m对明胶进行整体标记,然后将标记物~(99)Tc~m-明胶静脉注射于小鼠和家兔体内,检测不同时间后标记物的生物分布.结果表明,明胶可以被~(99)Tc~m所标记,且标记产物~(99)Tc~m-明胶放化纯大于95%;小鼠体内分布显示其具有较高肾摄取率,5 min时小鼠肾的摄取率达到29.36%/g,20 min时可以达到66.88%/g;家兔双肾显像清晰.说明~(99)Tc~m-明胶具有特异性肾分布的特点.