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时间：2005-12-20 19:46:15 编辑加入/取消收藏订制/取消短消息举报该贴

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回复人：wenchunlin,▲▲▲ (欢迎光临我的论坛http://www.happychem.com.cn/bbs) 时间：2005-12-20 19:59:35 编辑	1楼
免费查ACS！权限很大，要的联系我！乐意帮忙！

回复人：erro,★ (药物合成…… 希望认识更多的朋友) 时间：2005-12-20 20:08:40 编辑	2楼
楼主是不是查不到还赔钱啊!如果这样的话,我乐意请你提供服务! [该帖子已被erro在2005-12-20 20:09:04编辑过]

回复人：wenchunlin,▲▲▲ (欢迎光临我的论坛http://www.happychem.com.cn/bbs) 时间：2005-12-20 20:28:48 编辑	3楼
呵呵！同意erro的意见！呵呵

回复人：chslj,▲ (dd) 时间：2005-12-20 21:45:13 编辑	4楼
交流吗，收什么费用呀，比较无耻的，都是利用学校或者研究所的资源，想想都是学生，谁有钱呀

回复人：tangqiming,▲ (做有机合成碰到分离难问题，希望和大侠交流交流) 时间：2005-12-22 21:44:44 编辑	5楼
大家能查到Adv.Mater 2(1990)419 这篇文献的吗，有的话给点费用也可以，谢谢大家

回复人：erro,★ (药物合成…… 希望认识更多的朋友) 时间：2005-12-22 22:13:10 编辑

6楼

Superstructures and Band Gaps of
Bismuth Tantalum Oxide Solid Solutions **
By Wuzong Zhou*
Structures of many partially soluble solid solutions can be
described by means of a multi-order approximation. For
example, up to 23 mol '70 Nb,O, can be added into Bi,O, to
form defect fluorite-like solid solutions.['] In this solid-solution
range, X-ray powder diffraction (XPD) patterns for all
compositions were found to be very similar and can be indexed
to a cubic fluorite-like 6-Bi,03 lattice with a unit cell
parameter a of about 0.55 nm. However, the structures of
Bi,O, and Nb,O,, the radii of Bi3@ and Nb5@ cations, and
the coordination of these two cations by oxygen in normal
oxides are different. It is unlikely that the Nb5@ cations
would have the same environment as Bi3@ cations in these
materials and therefore there may be some more complex
structures inside the fluorite host lattice. Several different
types of superstructures have been discovered in this solidsolution
range by high resolution electron microscopy
(HREM). In the compositional range Bi,O, to Biz5Nb0,,,
the P-Bi,O, structure has been observed at room temperature.['
I From Bi,,NbO,, to Bi,,NbO,, , a 2 x 2 x 2 bodycentered
cubic superstructure (type I) was found. This is
based on the defect-fluorite lattice formed due to an ordering
of Nb cations,i31 where NbO, octahedra, being separate,
occupy the corner and the body-center sites. In the compositional
range Bi ,,NbO,, to Bi,NbO,, four NbO, octahedra
join together to form some Nb,O,, tetrahedral units and two
tetrahedra form an Nb,O,, cluster. These clusters lie on the

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