《CommunicationS in Theoretical Physics》投稿指南

正投稿要求:本刊只接收尚未在国内外公开发行的中英文刊物上发表过的、具有创造性研究结果的最新研究论文、简报和快讯,以及少量综述性论文。凡已向国内外其它刊物投稿的相同内容的文章,请勿再向本刊投稿。投稿方式:请以LaTeX、RevTeX、AMSTeX等tex文件和doc文件投稿,编辑部鼓励作者使用tex文件。当使用tex文件投稿时,请同时附上用所投的tex文件生成的pdf文件,     

Comparison of methods for vibration analysis of electrostatic precipitators

The paper presents two methods for the formulation of free vibration analysis of collecting electrodes of precipitators.The first,called the hybrid finite element method, combines the finit element method used for calculations of spring deformations with the rigid finite element method used to reflect mass and geometrical features,which is called the hybrid finite element method.As a result,a model with a diagonal mass matrix is obtained.Due to a specific geometry of the electrodes,which are long plates of complicated shapes,the second method proposed is the strip method which is a semi-analytical method.The strip method allows us to formulate the equations of motion with a considerably smaller number of generalized coordinates.Results of numerical calculations obtained by both methods are compared with those obtained using commercial software like ANSYS and ABAQUS.Good compatibility of results is achieved.     

A Computational Study on the Mechanism for the K_2CO_3-catalyzed Reaction of Carbon Dioxide and 1-Chlo-2-propanol

The microcosmic reaction mechanism of K2CO3-catalyzed 1-chlo-2-propanol and carbon dioxide has been investigated by density functional theory(DFT) at the GGA/PW91/DNP level.We optimize the geometric configurations of reactants,intermediates,transition states,and products.The energy analysis calculation approves the authenticity of intermediates and transition states.According to our calculations,four feasible reaction pathways are found.The main pathway of the reaction is ReA → IMA1 → TSA1 → IMA2 → IMA5 → TSA5 → P.Besides,we also in-vestigate the reaction mechanism of 1-chlo-2-propanol and carbon dioxide without K2CO3-catalyzation by the same theory and level.The computational results indicate that the activation barrier with K2CO3-catalyzed is smaller than the activation barrier without K2CO3-catalyzed.That is to say,K2CO3 can promote the reaction to give the product in a high yield,which is in agreement with the experimental results.     

挖掘网格图形几何特性,贯通三角函数求解路径——对一道中考试题的讲评与反思

一、试题展示题目如图1,在边长相同的小正方形组成的网格中,点A、B、C、D都在这些小正方形的顶点上,AB、CD相交于点P,则tan∠APD的值是________.这个问题是新近九年级三角函数单元测试的一个填空题,序号是第16题,来源于2012年泰州市中考数学试题第18题.简明的问题,简洁的网格图形,融几何、三角函数于一体,深受老师们的喜爱.但是考试结果出人意外,得分率很低.考后,笔者对这个问题进行了重点讲     

《从零学相对论》连载21

正§8.4水星近日点进动按照牛顿力学,行星的轨道是以太阳为一个焦点的椭圆.然而观测结果与此略有歧离.以最靠近太阳的水星为例,虽然它在每一周期中的轨道很接近椭圆,但两个相邻周期的两个"椭圆"的长轴并不重合,表现在它的近日点(perihelion)的微小改变上(见图8-6).随着时间的推移,由于积累效应,"椭圆"的长轴(因而近日点)绕太阳的缓慢转动变得可以观测.这现象叫做近日点的进动(precession).从1697至1848年的天文观测表明水星近日点的进动率是每世纪5 600″(″代表角秒).如何解释?法国数学家勒威耶(Le Verrier)用牛顿力学对水星运动做过长期研究,并于1859年再次发表研究报告.根据     

军校学员对MOOCs反应的调查

针对当前高等教育界的大型开放式网络课程（MOOCs）热潮,笔者对该校部分学员做了一次问卷调查,结果显示MOOCs在中国的发展仍处于萌芽的阶段,大部分学员对MOOCs知之甚少,但绝大多数学员对MOOCs这一新兴的教学模式很感兴趣,表示愿意尝试.大部分学习者表示选择MOOCs教学方式,更愿意在学校进行学习;MOOCs最大的优势是灵活、自由的学习方式.针对此调查,笔者对MOOCs的发展提出了4点建议,即制作MOOCs不必一拥而上、MOOCs制作要具有针对性、MOOCs的证书要与课程学分挂钩、推行＂混合式＂授课模式.     

The effects of cement density and pipe dimension on casing waves in oil wells

The acoustic field in a cased hole is studied through numerical modeling by combining experiment measurement when the first and scond interfaces are bonded well.The effects of the density of the cement,the diameter and thickness of the steel pipe on the amplitude of casing arrival(ACA) are investigated,and a part of the numerical results are compared with the experimental results.These results show that the ACA decreases with the increasing density of the cement.There exists a large difference between the ACAs for the low-and normal-density cements.Therefore,the different standard should be taken in the bonding evaluation for cements with different densities.As the thickness of the steel pipe increases while its diameter keeps as a constant,the arrival time of the casing wave remains unvaried,while the ACA increases. But,when the diameter of the pipe with a constant thickness increases,the arrival time of the casing wave is delayed,and the ACA decreases.As for three kinds of the steel pipe commonly used in oilfields,the relative amplitude of the casing arrival is larger in the big pipe. In addition,the numerical results of the varying trend of the relative amplitude of the casing arrival with the density of cements,on the whole,are in agreement with the experimental ones.     

原子吸收光谱法测定化妆品中铅、镉、铬、锌、铜和锰

重金属的危害越来越受到关注,它可以对动物体许多重要器官和神经系统造成损害甚至引发癌症和胎儿畸形。人们以前把主要注意力放在土壤、水和空气等经常直接或间接接触的污染源上。随着生活水平的提高,美容化妆已成为人们生活的一部分。目前化妆品不合格的报道经常出现,如含有重金属铬及其他致癌物质等。在化妆品卫生标准中,只列出对铅、汞和砷等元素的检测,一些化妆品中不仅含有上述元素,同时也含有镉、铬、