界面上的特异离子效应

结合物理化学教科书的相关章节,介绍卤化钠在固/液和气/液界面中的特异离子效应,提出在物理化学基础教学过程中应适当地结合相关领域的最新进展,拓宽学生的知识视野,更好地激发学生的学习兴趣。国家基础科学人才培养基金项目(No.J1210014

浅析物质在磁场中的受力

通讯联系人，E-mail: yuanrm@163． com[中文文摘]结合电磁学的基本原理，对古埃法测定物质磁化率实验中的受力情况进行了分析，并分析了误差 的主要来源和消除方法。简要介绍了法拉第法测量磁化率的工作原理。基金资助: 国家基础科学人才培养基金项目( No． J1030415

应用理论化学方法预测有机分子的标准摩尔生成焓

介绍一个针对高年级本科生开设的计算化学创新性实验,采用高斯理论计算一系列有机小分子的构型和热化学性质,并通过原子化反应法计算其标准摩尔生成焓。该实验可让学生初步掌握相关计算软件的使用,了解不同计算方法的适用范围,认识理论与实验相结合的实践途径。国家基础科学人才培养基金(No.J1210014

H_3反应势能面的构建——计算化学实验设计

介绍一个针对高年级本科生的物理化学探索性实验。通过计算化学手段构建H3反应势能面,使学生初步掌握gAuSSIAn03W,gAuSSVIEW5.0和OrIgIn软件的使用,深入理解反应过渡态理论,并进一步了解目前势能面的研究动态。国家基础科学人才培养基金项目(J1030415

Development of Practical Measuring-Controlling Equipment of Oxygen Bomb Calorimeter

本文介绍一种采用单片机控制 ,并配有新颖点火电路的氧弹式热量计测量控制仪。经试用具有精密、稳定的测温功能 ,并可控制搅拌及进行定时记录。A measuring controlling equipment of oxygen bomb calorimeter with a novel light circuit controlled by microprocessor was reported. This apparatus with recorder has a multi function to measure the temperature accurately and control the stir. The result of probatioon shows that this apparatus has an excellent measuring accuracy and a good stability.国家理科基地创建名牌课程资助项目!(教高司 98- 10 5号

旋光度法测定蔗糖转化反应速率常数实验用旋光管的改进

用旋光度法测定蔗糖转化反应速率常数是最基本的物理化学实验之一。该实验中的旋光管操作比较麻烦,且易引入实验误差。本文对该实验使用的旋光管进行了改进

Improvement on Liquid Saturated Vapor Pressure Measurement

针对目前静态法测定液体饱和蒸汽压实验中饱和蒸汽压数值读取不合理,汽液两相未充分平衡等问题,改变传统的调整u型管两端液面等高后再读取数字压力计的方法。改进后的实验装置只需在u型管的两侧标上刻度,待系统恒温、汽-液充分平衡后,读取数字压力计的数值、温度以及u型管两端液面的高度差就可得到该温度下的液体饱和蒸汽压。该方法可解决静态法测定液体饱和蒸汽压实验中调整u型管两端液面等高耗时,空气容易倒灌的问题。This paper presented a method to improve the unreasonable design of liquid saturated vapor pressure measurement obtained by static method.The improvement changed the traditional method for measuring the liquid saturated vapor pressure which cannot get the pressure data until both sides of the U-type tube reach the same heigh of liquid level.After marking graduated lines on the two sides of the U-type tube,the liquid saturated vapor pressure can be easily obtained from digital pressure gauge,after the temperature becomes constant and the difference in the height of liquid level is balanced.The time-consuming problem of adjustment of liquid level height on both sides of the U-type tube and the problem of air flow backward could be solved perfectly.It is very helpful to enhance student's understanding of the concept of vapor-liquid equilibrium.国家基础科学人才培养基金项目(J1030415

Kinetics of Vesicle Formation and Breakdown

利用停流装置研究了十二烷基硫酸钠(SDS)和十二烷基三甲基溴化铵(DTAB)复配形成囊泡的过程和囊泡破坏过程的动力学性质,并结合动态光散射技术和电子透射显微镜探索囊泡形成和囊泡破坏过程的机理.动态光散射和电子透射显微镜的研究结果表明囊泡的形成过程主要包括四个阶段:混合胶团→柔性的长棒状聚集体→"非平衡囊泡"→平衡囊泡,而与其对应的粒度分散度则呈现"单分散性→多分散性"的周期性变化规律.此外,动力学结果表明囊泡形成过程很长,但其活化能不大,这意味着囊泡形成过程的控制步骤可能不是活化能控制.而相对于囊泡的形成,囊泡的破坏过程是十分迅速的.A combination of stopped-flow,transmission electron microscopy and dynamic light-scattering techniques has been used to study the kinetics of vesicle formation and breakdown as well as the mechanism of vesicle formation and breakdown in DTAB/SDS aqueous solutions.The results show that the process of vesicle formation can be modeled as a sequence of distinct processes:mixed micelles→flexible stick-shaped aggregates→non-equilibrium vesicles→equilibrium vesicle system,and the evolution of particle dispersion degree appears to be a periodical change of "monodispersity→polydispersity".In addition,the kinetic analysis shows that the process of vesicle formation lasts for a long time.However,the activation energy of vesicle formation is not too high,which implies that the control procedure of the process is independent of activation energy.In contrast to the process of vesicle formation,vesicle breakup to mixed micelles appears to be a rapid process.厦门大学科技创新重点项目(No.XMKJCX20052001)资助项目

Influence of Spacer Chain Length on the Rheological Properties of Gemini Surfactant

用毛细管振荡剪切流动法研究了联接基团为聚亚甲基链的阳离子 Gemini表面活性剂的流变性质。实验结果表明 ,无论是普通单链单头基或 Gemini表面活性剂 ,其流变性质主要由胶团的大小和形状所决定 ;随着联接基团长度的增加 ,胶团的轴比率变小 ,导致流动阻力减小 ,粘度降低。此外对于球形和棒状胶团溶液 ,其流变性质主要以粘性为主 ,弹性可忽略不计。在低剪切速率下 ,溶液属于牛顿型流体 ;而在高剪切速率下 ,则表现出准塑性流体性质。By the means of oscillatory shear flow in the capillary, rheological experiments are carried out on aqueous solutions of the cationic Gemini surfactant as a function of suffactant concentration. The results show that the rheological property is mostly determined by the size and shape of micelles. The axial ratio of micelles decreases with increasing the length of spacer chain, so the viscosity of solution decreases.国家自然科学基金资助项目 (2 99730 33

Micellar Growth of Quaternary Ammonium Gemini Surfactant in Aqueous Solutions Using Dynamic Light Scattering

用动态光散射技术在 10～ 70℃温度范围内 ,通过测定胶团的平均流体力学半径随温度、盐浓度和联接基团长度的变化情况 ,研究联接基团为聚亚甲基链的阳离子季铵盐Gemini表面活性剂胶团在无机盐介质中的长大规律 .实验结果表明 ,增加盐量、降低温度和减小联接基团的长度均使平均流体力学半径变大 ,Gemini表面活性剂胶团长大时是由球状转变为棒状 .从实验测定的平流体力学半径求算了支配球 -棒转变的平衡常数及热力学函数值 ,并用NNLS (non negativelyconstrainedleastsquare)算法对胶团的粒径分布情况进行了分析 .此外 ,对具有短联接基团的Gemini表面活性剂胶团长大所具有的独特性质进行了讨论 .The micellar growth of quaternary ammonium Gemini surfactants containing methylene group spacer (referred to as C 12-s-C 12, 2Br) in inorganic salt (NaBr) media was investigated by using dynamic light scattering. The size of micelles increases with increasing salt concentration or decreasing temperature or decreasing the length of spacer chain. The enlarged micelles have a shape of prolate ellipsoid or rod. Based on these mean hydrodynamic radius (R h) measurements, values of the thermodynamic parameter K governing the sphere to rod transition were determined. Numerical values of enthalpy and entropy change for this transition were deduced from the linear plot of ln K vs. 1/T. The novel micellar growth of C 12-2-C 12, 2Br was discussed. The distribution of micelle size was analyzed by using non-negatively constrained least square (NNLS) algorithm.国家自然科学基金 (No .2 99730 33)资助项