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关键词： 物料衡算法   离子迁移数   物理化学  

摘要： 从定义出发,通过公式推导、简单图解法、物料衡算法和例题分析,对离子迁移数的概念进行了剖析,并得到了相应等式.通过学习能够熟练掌握离子迁移数本质内容,提高学生学习物理化学的兴趣.

关键词： 物理化学   实践教学   实践能力   学习评价  

摘要： 研究了"物理化学"课程通过开发综合性实验、学生独立设计实验及实验室开放等途径培养学生的实践创新能力的问题。同时,对学生实验成绩的评价方式进行了改革探索。

关键词： 材料专业   物理化学   知识体系   认知方法  

摘要： 从材料专业视角重新审视了经典的物理化学课程。将材料专业知识体系的特征贯穿于物理化学课程,以弱化该课程的化学化工属性,突出材料属性;结合认知方法改造,对教材结构做出调整,为建设名副其实的材料物理化学课程奠定理论基础。

关键词： 物理化学   发射药   燃烧转爆轰   冲击波  

摘要： 为研究发射药燃烧转爆轰特性及其影响因素,采用联合国危险分级试验中燃烧转爆轰试验方法对单、双、三基以及不同药型的发射药进行燃烧转爆轰试验。结果表明,在管厚4mm弱约束条件下,只有三基小粒发射药发生爆轰,在管厚9mm强约束条件下,6/7双基药、6/7叠氮发射药、6/7三基药以及三基小粒药发生爆轰。发射药配方中添加硝化甘油(NG)、叠氮硝胺(DA)和黑索金(RDX)以及减小药型尺寸,可增强发射药的燃烧转爆轰能力,同时,提高壳体约束强度更易发生燃烧转爆轰。

关键词： 物理化学   比较法   类比法   记忆法   程式化方法  

摘要： 针对高校学生掌握物理化学较难的特点,介绍了一些学习中的窍门和方法。通过比较法找出公式和现象中的相似和关联,可以加强记忆与理解;运用类比法将抽象的新知识纳入到已有的知识体系中,可达到触类旁通的效果;将科学记忆法融入学习中,可达到事半功倍的效果;善用程式化方法,使解题更加标准、快捷。多种方法并用,可以激发学生分析问题﹑解决问题的积极性和主动性,使物理化学的学习变得更加轻松﹑简单。

关键词： Lipophilicity   log P   QSAR   Topological descriptors  

摘要： In the present work we have considered miscellaneous set of 76 industrial chemicals and modeled their logP using topological as well as physicochemical descriptors. The results indicate that the estimation of log P is very much effective when the topological and physicochemical descriptors are used together. The most appropriate model for the estimation (modeling) of log P indicated that by using the combination of topological and physicochemical descriptors. The results are discussed using variety of statistical approaches. [ABSTRACT FROM AUTHOR]

关键词： 物理化学   高等学校   教材  

摘要： 本书共分十章，内容包括绪论、气体、热力学第一定律、热力学第二定律、多组分系统热力学、化学平衡、相平衡、电化学、化学动力学基础、界面现象、胶体分散系统与大分子溶液。

关键词： Sulfonated PVDF-HFP/1H-1,2,4-Triazole   Proton conducting membrane   Sulfamic acid   Fuel cell   EXCHANGE MEMBRANES   FUEL-CELLS   ELECTROLYTE   MONOMERS   FILMS  

摘要： A new material for proton conducting electrolyte base on sulfonated poly(vinylidene flouride-hexafluoropropylene) (PVDF-HFP)/1H-1,2,4-Triazole (Tri Delta) membrane operating at low relative humidity and has capability to self-humidify were investigated. Different concentrations of TriA and sulfamic or amidosulfonic acid (H3NSO3) in PVDF-HFP were prepared. The pores of a porous PVDF-HFP were packed with proton carrier, TriA and sulfamic acid (SFA). The samples were then exposed to gamma-rays of up to 50 kGy. The effects of high energy gamma-rays irradiation onto these proton conducting membranes have been observed. The surface morphology was analysed by scanning electron microscopy (SEM). The ionic conductivity of the irradiated membrane was determined using impedance spectroscopy (IS) at different temperatures between 30 degrees C and 100 degrees C. The results showed that the pores membranes shrinkage after irradiation and proton conductivity of the membrane increased when the absorbed dose up to 30 kGy and after which the proton conductivity decreased with increasing of absorbed dose.

关键词： SNO2 THIN-FILMS   ELECTRICAL-PROPERTIES   OPTICAL-PROPERTIES   STRUCTURAL-PROPERTIES   SPRAYED SNO2   TRANSPARENT   TEMPERATURE   DIFFRACTION   IRRADIATION   ABSORPTION  

摘要： The physical and chemical properties of spray deposited FTO films are studied using FESEM, x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), electrical and optical measurements. The results of XRD measurements showed that the films are polycrystalline (grain size 20-50 nm) with Rutile structure and mixed preferred orientation along the (200) and (110) planes. An angular shift of the XRD peaks after F-doping is observed and interpreted as being due to the formation of substitutional fluorine defects (F-O) in presence of high concentration of oxygen vacancies (V-O) that are electrically neutral. The electrical neutrality of oxygen vacancies is supported by the observation that the electron concentration n is two orders of magnitude lower than the V-O concentration calculated from chemical analyses using XPS measurements. It is shown that an agreement between XPS, XRD, and Hall effect results is possible provided that the degree of deviation from stoichiometry is calculated with the assumption that the major part of the bulk carbon content is involved in O-C bonds. High temperature thermal annealing is found to cause an increase in the F-O concentration and a decrease in both n and V-O concentrations with the increase of the annealing temperature. These results could be interpreted in terms of a high temperature chemical exchange reaction between the SnO2 matrix and a precipitated fluoride phase. In this reaction, fluorine is released to the matrix and Sn is trapped by the fluoride phase, thus creating substitutional fluorine F-O and tin vacancy V-Sn defects. The enthalpy of this reaction is determined to be approximately 2.4 eV while the energy of formation of a V-Sn through the migration of Sn-Sn host atom to the fluoride phase is approximately 0.45 eV. (C) 2012 American Institute of Physics. [http://***/10.1063/1.4736798]

关键词： 物理化学   课堂教学   主动性  

摘要： 物理化学课程是化学化工类专业重要的基础理论课,是一门比较抽象且理论性较强的课程,学生普遍感到难学。在以往的教学过程中,学生的主动性较差。文章从教学目标、教学内容、教学方法等方面入手,探讨了如何提高学生在《物理化学》课程教学中的学习兴趣、自学能力和学习主动性。