（η^2—C60）[Pt（PPh3）2]8的合成与表征

C60是高度共轭的宠状结构碳素体．分子结构中六元环间的共价碳碳双键是富电子区，其反应性能与烯键类似，以碳碳双键与中心金属形成η2配位化合物．富勒烯η2配合物的合成及性能研究是当前研究热点之一[1~7]．本文在（η2-C60）［Pt（PPh3）2］n（n=1～6）系列研究[7]的基础上制备了（η2－C60）［Pt（PPh3）2］8，并用元素分析、红外光谱和光电子能谱进行鉴定和表征．1实验部分四（三苯基膦）合铂Pt（PPh3）4按文献[8]方法制备；C60纯度为99％；其余试剂均为分析纯．元素分析在ERLA－1106型元素分析仪上进行；光电子能谱在VGESCA…     

过渡金属乙酰丙酮螯合物的体积排除色谱研究

用定量体积排除色谱方法研究了过渡金属Fe(Ⅲ)、Co(Ⅲ)、Cu(Ⅱ)、Ni(Ⅱ)的乙酰丙酮螯合物在四氢呋喃溶液中的加合和缔合行为。在溶液中乙酰丙酮钴(Ⅲ)以单个螯合物分子的形式存在,乙酰丙酮铜(Ⅱ)和乙酰丙酮铁(Ⅲ)与溶剂加合生成加合物,乙酰丙酮铁(Ⅲ)除加合物外还存在缔合度为2-10的多分散缔合物,乙酰丙酮镍(Ⅱ)水合物在四氢呋喃中产生了加合交换作用,同时存在缔合度为6左右的缔合物。色谱数据给出了螯合物、加合物及缔合物     

一种新的判断高分子相容性的粘度判据

依据最近提出的高分子稀溶液粘度的浓度 依赖性的团簇理论 ,对高分子‘理想混合物’的定义进行了更新的理论分析 .在此基础上提出了一个新的判定高分子相容性的粘度判据 .从现有的大量实验数据看 ,该判据是和事实相符合的     

水合醋酸铈直接热分解制备超细氧化铈及其抛光性能

Ultra fine ceria was prepared by calcining hydrate cerium acetate. The effects of pyrolysis temperature on the particle size, morphology, specific surface area and loose packing density of ceria were investigated, and the removal rate of optical glasses polishing by ceria was determined. The results show that with the increase of pyrolysis temperature, the loose deposit density and crystallinity increases and the specific surface area decreases, however, the particle size decreases firstly and then increases, the minimum medium particle size D₅₀ is 0.47 μm at pyrolysis temperature of 1 000 ℃. The SEM images of ceria prepared by the decomposition at 800 ℃ or at 1 100 ℃ show porous powders or quasi-sphere small particles with loosely agglomeration, respectively. It was found that the removal rate varied with pyrolysis temperature in preparation of ceria and the property of glass polished. The removal rate for three kinds of glasses was in the order of ZF7> F1> K9, and the maximum value appeared at around 1 000 ℃ for ZF7 and F1, and at around 1 100 ℃ for K9.     

Dy对Pt—Dy／Al2O3催化剂表面吸附中心性质及其催化性能的影响

通过脉冲微型反应催化色谱装置，考察了正己烷在Ｐｔ／Ａｌ２Ｏ３和Ｐｔ－Ｄｙ／Ａｌ２Ｏ３催化剂上的转化反应：用ＴＰＤ、ＴＰＲ和ＨＯＴ技术研究了Ｐｔ－Ｄｙ／Ａｌ２Ｏ３催化剂的表面性质。     

低温丁苯橡膠的分子量分佈

由於性能上的優點,生產量最大的丁苯橡膠,近年來已逐漸趨向於使用低溫聚合產物。高聚物的性質与高分子的分子量、分子量分佈以及化學結構有着密切關係,高溫聚合的丁苯橡膠分子量分佈測定的結果,從粘度數據推斷,約有25％的丁苯橡膠分子有顯著的支化或交聯。本工作對一個低轉化率(16％,試樣Ⅲ)和一個較高轉化率(66％,試樣Ⅰ)的低溫(5°)乳液聚合的丁苯橡膠,用分級沉澱和粘度法測定了它們的分子量分佈。     

Li3AlB2O6： Synthesis, Crystal Structure, and Its Luminescence Property Compared with LiSrBO3

The synthesis and crystal structure of Li3AlB2O6 with different cell parameters are reported and these cells are transformed each other from the confirmation of crystallographic structural analyses. The absorption spectrum, luminescence and lifetimes of the Li3AlB2O6 and LiSrBO3 solid compounds are measured and the comparisons are made between them. It is shown that the absorption edges are at about 400 nm (or band gap 3.1 eV) and there is one of absorption peaks at about 350 nm for the Li3AlB2O6 and LiSrBO3. The emission band (530 nm) makes a red shift and fluorescence decay time (24.39 ns) of the Li3AlB2O6 becomes smaller compared with the emission band (480 nm) and lifetime (93.16 ns) of the LiSrBO3 at the visible region. The transition energies and oscillator strengths of the clusters (Li3AlB2O6)2 and (LiSrBO3)2 lying at low excited states are calculated by the time-dependent Hartree-Fock method. The obtained results are used to model the photophysical properties and discuss the origin of spectral bands of the Li3AlB2O6 and LiSrBO3.     

新式夹心型光透薄层光谱电化学电解池

本文设计了一种新式夹心型光透薄层紫外-可见光谱电化学池。该池采用铂网工作电极,两侧平行放置铂片为对极置于同一石英窗口夹层中,同时以聚四氟乙烯隔离膜作为边际限制器,结合池内小孔道设置内参比点进行精确的电位控制,具有理想的光谱电化学响应。利用循环伏安、循环电位-吸收、恒电位现场光谱、双电位跃-计时电量、双电位跃-计时吸收等技术,对铁氰化钾在氯化钾溶液中的行为进行了表征。     

并联换热系统中冷媒分配的优化分析

为减小并联换热系统的质量,本文在一定的简化和假设之上,建立了其流动与传热的物理和数学模型;并以系统总换热面积最小为优化目标,通过对分配系数的变量转换,提出了一种可准确求解最佳分配系数的方法,并对计算结果进行了讨论,发现分配系数的结果与势容耗散最大基本一致.根据计算结果.本文给出了支路较少时分配系数与换热支路效能之间的近似关联式.     

镜面Heisenberg-Virasoro代数的导子代数和自同构群

本文研究镜面Heisenberg-Virasoro代数的导子代数和自同构群,确定该代数的外导子和系数在它自身的一阶上同调群.