X射线分光晶体TAP的振动模对称类和Raman光谱研究

本文根据空间群商群与点群的同形原理，对同晶型晶体ＴｌＣ８Ｈ５Ｏ４和ＫＣ８Ｈ５Ｏ４的振动模对称类进行了讨论．这类晶体中的邻苯二甲酸基团具有正规子群对称性．本工作分析和讨论了它对于喇曼光谱的主要贡献，并根据基团的键振动特性对谱图作了初步识别．通过对低波数范围金属离子振动谱的比较，得出与Ｐ．Ｇ．Ｐｕｒａｎｉｋ［印］的论点不同的结果。     

O(3^P)+C~2F~4反应的动力学过程

对O(~3P+C_2F_4反应动力学的详细研究始于1976年.交叉分子束实验和流动余辉实验相继测得该反应的分支比,角分布和速度分布及内态分布.Bogan用相空间理论对该反应进行了近似计算.本文则由前文的结果,通过机制分析得到CF_2(~3B_1)的初生弯曲振动态相对布居和C_2F_4对CF_2(~3B_1)的弯曲振动弛豫常数,并对该结果进行了分析和讨论. 初生内能态分布和振动弛豫常数的计算前文结果如表1所示.其中C_2F_4的分气压由测得的总气压随C_2F_4流量的变化而推得,表中同时给出了态分布的拟合值. 产生观察到的内能态布居的过程可概括如下:     

Viscoelasticity and morphology of an organic hybrid of chlorinated polyethylene and N,N′-dicyclohexyl-2-benzothiazolyl sulfenamide

The viscoelasticity and morphology of an organic hybrid of chlorinated polyethylene (CPE) and N,N′-dicyclohexyl-2-benzothiazolyl sulfenamide (DBS) were studied by means of tensile and shear complex modulus and differential scanning calorimetry (DSC) analysis. Tensile and shear loss modulus (E″ and G″), which are shown as indexes of vibration damping performance, showed one peak corresponding to the glass transition. The peak maximum values (E″_max and G″_max)increased in proportion to DBS content ( _DBS) and the slope of E″_max against _DBS became steep above a certain DBS content, i.e. the critical DBS content ( _c). A high damping material was obtained by the addition of DBS, especially when DBS content was higher than _c. These increases in loss moduli below and above _c are caused by the interaction between CPE and DBS molecules and the friction between DBS molecules, respectively. It was found that CPE/DBS is a compatible blend at all DBS contents from the analysis of the glass transition temperature with DSC. Furthermore, the influence of chlorine content in CPE on those characteristics was investigated. Higher chlorine content led to lower _c, a decrease in E″ below _c and an increase in E″ above _c. These results are due to the increase in the number of dichloromethylene units (CCl₂), which reduces the α-hydrogen atom in CPE.     

烷基极化效应与X=O键伸缩振动频率

烷基取代物R'X=O的X=O键伸缩振动频率ν与烷基R的极化效应指PEI(R)的关系可表示为:ν=a+bPEI(R)。研究结果表明,烷基的极化效应使X=O键的伸缩振动频率降低。     

C6240F车床振源分析

本文以测振仪测出Ｃ６２４０Ｆ车床受迫振动振幅大小，再经过频率分析仪进行频率分析，得出频谱曲线，曲线上各峰值对应的频率有些是振源的频率，以此找出振源．试验中，通过改变主传动链传动环节的不同组合情况分析各振源的影响，得出对机床影响最大的受迫振源，以便改进结构设计和装配质量．