优化几何构型对高级别从头算能量的影响

对《ＣＲＣ物理与化学手册》（第７７版）中第三周期以前的无机双原子分子,当其理论优化构型的相对误差大于２％时,分别在实验构型和最大偏差的理论构型下,计算了ＱＣＩＳＤ（Ｔ）／６－３１１＋Ｇ（３ｄｆ,２ｐ）能量并作了比较。结果表明,大多数能量的差别在４．２ｋＪ．ｍｏｌ＾－１以内。由此说明,目前一般采用的构型优化理论方法,多数情况下不至于明显影响单点高级别从头算的计算精度。同时还发现,Ｇ２（ＱＣＩ）的高级     

The photoluminescence of Co-Al-layered double hydroxide

We report a new optical behaviour of pure Co-Al-layered double hydroxide (LDH).It was found that the Co-Al-LDH sample could emit fluorescence without any fluorescent substances intercalated.Its excitation spectrum shows a maximum peak near the wavelength 370nm,the maximum emission peak appears at 430 nm and the photoluminescence colour of the Co-Al-LDH sample is blue.This new optical property will be expected to extend the potential applications of LDHs in optical materials field.     

A new reaction for the direct conversion of 4-azido-4-deoxy-D-galactoside into a 4-deoxy-D-erythro-hexos-3-ulose

[reaction: see text] A new one-step reaction has been developed for converting 4-azido-4-deoxy-d-galactoside into 4-deoxy-d-erythro-hexos-3-ulose by phosphoramidites and tetrazole. It is proposed that the new reaction proceeds via an intramolecular Staudinger reaction of the phosphite intermediate and a tetrazole-catalyzed elimination reaction of the resultant phosphorimidate. Tetrazole appears to be playing a unique role by acting as a bifunctional catalyst to facilitate the elimination reaction.     

BaLaB_9O_（16）中Ce~（3＋）敏化Dy~（3＋）发光的机理

在紫外光激发下，研究了ＢａＬａＢ９Ｏ（１６）中Ｄｙ（３＋）、Ｃｅ（３＋）的发光光谱、激发光谱、发光强度及荧光寿命随着组成变化的规律性．结果表明：Ｄｅ（３＋）对Ｄｙ（３＋）的发光有相当强的敏化作用，Ｃｅ（３＋）→Ｄｙ（３＋）的能量传递效率可高达９３％，能量传递的机理为电偶极－偶极相互作用的共振传递．根据３４９ｎｍ激发下Ｄｙ（３＋）发光强度与浓度的关系，证明了Ｄｙ（３＋）发光的自身浓度猝灭机理也为电偶极－偶极相互作用．     

杉木针叶磷脂酰甘油脂肪酸组成分析

用改进的DEAE阴离子交换柱色谱法和硅胶薄层色谱法分离制备杉木针叶磷脂酸甘油，用气相色谱法测定了它的脂肪酸组成。分析结果表明，抗寒性强的杉木品种的针叶磷脂酰甘油脂肪酸的（18:1＋18:2＋18:3）／[16:0＋16:1（3t）]比值比不抗寒品种的高。     

Determination of DNA using sodium 9,10-anthraquinone-2-sulfonate as an in situ photochemical fluorescence probe

An in situ photochemical fluorescence probe method for the determination of DNA with sodium 9,10-anthraquinone-2-sulfonate (AQS) as a photochemical fluorescence probe was developed. It was based on the conversion of AQS into an intensively fluorescent product by irradiating with UV radiation. The photochemical reaction is retarded by DNA. The determination can be carried out by measuring the fluorescence intensity at a fixed time. The calibration graph was linear in the range 0–80 ng ml⁻¹ calf thymus (CT) DNA (r = 0.9991), the limit of detection was 3.2 ng ml⁻¹ CT DNA (n = 9). The kinetic behaviour of the photochemical reaction and the effects of experimental conditions were investigated and discussed in detail. The results of absorption spectra and competitive binding experiments suggested the interaction between AQS and DNA to be intercalative.     

聚苯乙烯负载聚乙二醇在合成碳酸亚丙酯上的应用

用金属钾、金属钠以及氢氧化钠水溶液等方法制备聚苯乙烯负载聚乙二醇，结果表明，采用金属钾比金属钢具有更好的接枝效果，并能使反应在较低的温度下较快进行。在氢氧化钠溶液中添加少量相转移剂，如Bu4NBr，接枝效果也有所提高。以聚苯乙烯负载聚乙二醇和KI一起为催化剂，研究了溶剂、温度等因素对CO2与环氧丙烷合成碳酸亚丙酯催化活性的影响。结果表明，以甲醇为溶剂催化活性较高。研究还表明，聚苯乙烯负载聚乙二醇具有较好的热稳定性，可以在150℃下重复使用至少5次。     

碳纤维汞膜微电极1.5次微分伏安法测定米托蒽醌的研究

米托蒽醌（ＭＸＴ）能吸附在碳纤维汞膜微电极表面，阴极溶出时，产生一个灵敏的１．５次微分溶出峰，其峰电流和米托葱酿的浓度在１．０×１０－５ｍｏｌ／Ｌ～１．３×１０－９ｍｏｌ／Ｌ范围内具有良好的线性关系，经３ｍｉｎ的富集，检出限可达１．０×１０－１０ｍｏｌ／Ｌ，据此建立了测定ＭＸＴ的灵敏的新方法，本文讨论了实验条件，并对血样中的ＭＸＴ进行了测定。     

碳纤维微电极研究(Ⅺ)——利用温度效应测定电极反应的热力学和动力学参数

研究了温度对碳纤维微电极上伏安曲线的影响及温度与电极电位的关系,测定了电极反应的热力学参数.由电流与温度的关系测定了去极剂的扩散活化能E_(al)和D_o,利用微电极具有高速传质的特性,测定了常规电极上为可逆反应的电极反应标准速率常数(?),并通过(?)与温度的关系测定了电极反应的活化能.     

SDS/n－C5H11OH/n－C7H16/H2O体系中W/O－BI微乳液界面电性质

In the system of SDS/n-C5H11OH/n-C7H16/H2O with the weight ratio of SDS/n-C5H11OH/H2O system at5.0/47.5/47.5, the upper phase of the system was W/O microemulsion, and the lower phase was the bicontinuous microemulsion. When the n-heptane content was less than 1%, with the increase of the n-heptane content, the capacitance (Co, Cod) in the upper phase (W/O) dropped, the capacitance (CB1, CBld) in the lower phase (BI) raised. At the same time, the W/O-BI inteffacial potential (ΔE), capacitance (Ci), and charge-transfer current (ict) decreased.After the n-heptane content reached 1%, with the increase of the n-heptane content, ΔE, Ci and ict demonstrated no significant change.