关于范德瓦耳斯方程中b的一种简单估算方法

本文用分子的刚球模型给出计算分子“平均自由活动空间”的简单方法，推算出范德瓦耳斯方程中ｂ的数值是 １摩尔气体分子本身总体积的 ４倍．物理图象较清楚、在教学中易被接受和理解．     

范德瓦耳斯方程压强修正项的定量推导与改进

范德瓦耳斯方程压强修正项的定量推导与改进唐郁生（玉林地区教育学院广西玉林５３７０００）１引言学过热学的人都知道，１ｍｏｌ气体的范德瓦耳斯方程为（ｒ＋ａｖ２）（ｖ－ｂ）＝ＲＴ（１）它考虑到分子具有体积，分子间又具有引力，对理想气体状态方程的压强和体积...     

范德瓦耳斯方程中的b和斥压强

普通物理中讨论范德瓦耳斯方程时,从气体分子的刚球引力模型出发,考虑了实际气体分子的体积引入了改正量b。同时认为确切地讲,b是分子间斥力所引起。[1]但是,究竟改正量b和分子间斥力有什么关系,则没有说明。本文从分子的刚球引力模型出发定量的讨论了b和分子间斥力引起的压强的关系,并导出范德瓦耳斯方程。证明范氏方程中的b约等于一摩尔气体分子体积的四倍。最后用刚球引力模型对范氏气体的内能作了说明。 (一)从一个思考题谈起[2] 题目:在讨论理想气体的压强时,设想在气体内取一小截面 dA,则两边气体通过截面 dA互施压力,试从分子运动论…     

从气体吸附率看范德瓦耳斯气体模型的局限性

利用占据数方法和正则系综理论分别求出了费米气体、玻色气体和范德瓦耳斯气体的化学势,比较了这三种气体与理想气体吸附率的差异.指出:费米气体的吸附率高于理想气体,玻色气体则低于理想气体.存在一个临界温度,高于此温度,用范德瓦耳斯气体描述费米气体不如理想气体模型;低于此温度,用范德瓦耳斯气体描述玻色气体不如理想气体模型.     

范德瓦耳斯气体体积修正的新计算方法

范德瓦耳斯方程能够较好地描述实际气体的热力学过程,方程中的参数b是因实际气体分子的体积而引入的修正量.本文通过考察分子之间的相互碰撞事件,计算得到了范德瓦耳斯气体体积的修正值,约等于1 mol气体所有分子体积总和的4倍,结果与其他方法得到的结果一致.这是一种新的计算思路和方法.     

玻尔兹曼因子方法 打开了精确计算分子相互作用特性的大门

范德瓦耳斯方法只考虑了分子之间的吸引力, 未考虑排斥力, 所以范德瓦耳斯方程与实际气体并不十 分符合. 玻尔兹曼因子方法既包含了分子之间的吸引力, 也包含了相邻分子之间的排斥力, 巧妙地克服了“ 统计物理 学处理互作用粒子系统所遇到的困难” , 所以由玻尔兹曼因子方法推导出来的实际气体玻尔兹曼因子方程, 不仅与 传统基础知识一脉相承, 涵盖了理想气体物态方程、 范德瓦耳斯方程与维里方程, 而且真正打开了在定量上精确计 算分子相互作用特性的大门, 实现了精确计算摩尔表面自由能及其相关物理量的目标; 较好地解决了范德瓦耳斯方 程所存在的公认缺陷问题     

试论范德瓦耳斯气体

物理学中的范德瓦耳斯体积改正量b不应当是分子体积总和b1的4倍。分子的自由活动空间不仅与分子体积总和、分子处于最紧密状态时的间隙有关,还与分子本身的运动有关。研究的结论是体积改正量b为分子体积总和b1的2.7倍。     

重力场中的范德瓦耳斯气体

将地球大气近似为重力场中的范德瓦耳斯气体,在绝热过程近似下导出了大气温度、压强随高度的分布,并与理想气体近似结果进行了比较分析.     

自制吸附仪储氢性能测试研究

针对全自动吸附仪只能在低压范围内（小于1个大气压）进行吸附研究的缺点,自行设计并生产了一套测量材料吸附性能的仪器,相比于自动吸附仪,此仪器扩大了压力适用范围.应用自制吸附仪,分别运用理想气体状态方程和范德瓦耳斯方程计算了间苯二酚-甲醛碳气凝胶的储氢吸附量. 关键词： 储氢 范德瓦耳斯方程 吸附     

理想气体状态方程——从经典到量子

1 经典理想气体状态方程 1662年玻意耳和1679年马略特发现气体的压强p和体积V的乘积,在温度T一定下,是一个常量,称为玻意耳-马略特定律.     

气相色谱法分析天然气成分

本文研究了气相色谱法测定天然气成分的分析方法,确定了计算方法及工作条件,并实测了城市燃气用天然气的常规成分,获得了满意的结果。     

Plasma Properties and Neutral Gas Densities in Hg-Rare Gas Discharges

The density of the neutral gases in Hg-rare gas discharges and their spatial distribution is controlled by the discharge parameters as well as by the externally adjustable partial pressures. Essential quantities in this context are the gas temperature produced by elastic collisions, the ion transport by the discharge current, the processes governing the wall temperature, and ambipolar diffusion. Despite equal partial pressures different densities may occur, which, in turn, will influence the parameters of the discharge. This has effects on the assessment of the methods of Hgvapour pressure adjustment and on the evaluation of the measured values. These effects are demonstrated, especially by field strength measurements, for a wide parameter range.     

Two-Dimensional Quantum Gas

Identical impenetrable particles in a 2-dimensional configuration space obey braid statistics, intermediate between bosons and fermions. This statistics, based on braid groups, is introduced as a generalization of the usual statistics founded on the symmetric groups. The main properties of an ideal gas of such particles are presented. They do interpolate the properties of bosons and fermions but include classical particles as a special case. Restriction to 2 dimensions precludes lambda points but originates a peculiar symmetry, responsible in particular for the identity of boson and fermion specific heats.     

Gas body activation

A small body of gas which is stabilized against dissolution in a liquid by a supportive structure may oscillate in response to an ultrasonic field and this form of cavitation is termed gas body activation. Linear theory describes the response of gas-filled intercellular channels in plant tissue and of gas-filled micropores in thin sheets of plastic. Calculations from this theory yield good agreement with indirect observations of resonance frequencies and rough agreement with direct measures of aggregate response (transmission and reflection coefficients). Studies of gas body activation in biological systems should allow quantitative analysis of cavitation bioeffects for relatively low-intensity ultrasound applications.     

Investigation of Eco-Friendly Gas Mixture for Gas Discharge Particle Detectors

Physics of Atomic Nuclei - The first results of studying the Ar/CO2/HFO1234ze eco-friendly gas mixture for gas discharge detectors are presented. The work is performed using a prototype multiwire...     

燃气热值计量标准的尾气收集装置精度设计

针对基于燃烧法的燃气热值计量标准的尾气收集装置的缸体容积精确测量问题,应用现代仪器精度与误差理论,对该尾气收集装置的各项误差源进行分析,得到各分量的传递系数表达式,并按工程实际情况对精度指标进行了分配与调整;对分配的精度指标进行了合成计算,结果表明所设计的燃气热值计量尾气收集装置的最大允许误差为0.24％,完全满足尾气体积的测量精度要求;论文研究对建立我国新一代天然气热值计量标准有很好的指导意义和工程实用前景。     

Optical analysis of trapped Gas—Gas in Scattering Media Absorption Spectroscopy

An overview of the new field of Gas in Scattering Media Absorption Spectroscopy (GASMAS) is presented. The technique investigates sharp gas spectral signatures, typically 10000 times sharper than those of the host material, in which the gas is trapped in pores or cavities. The presence of pores causes strong multiple scattering. GASMAS combines narrow-band diode-laser spectroscopy, developed for atmospheric gas monitoring, with diffuse media optical propagation, well-known from biomedical optics. Several applications in materials science, food packaging, pharmaceutics and medicine have been demonstrated. So far molecular oxygen and water vapour have been studied around 760 and 935 nm, respectively. Liquid water, an important constituent in many natural materials, such as tissue, has a low absorption at such wavelengths, and this is also true for haemoglobin, making propagation possible in many natural materials. Polystyrene foam, wood, fruits, food-stuffs, pharmaceutical tablets, and human sinus cavities (frontal, maxillary and mastoideal) have been studied, demonstrating new possibilities for characterization and diagnostics. Transport of gas in porous media (diffusion) can be studied by first subjecting the material to, e.g., pure nitrogen, and then observing the rate at which normal, oxygen-containing air, reinvades the material. The conductance of the passages connecting a sinus with the nasal cavity can be objectively assessed by observing the oxygen gas dynamics when flushing the nose with nitrogen. Drying of materials, when liquid water is replaced by air and water vapour, is another example of dynamic processes which can be studied. The technique has also been extended to remote-sensing applications (LIDAR-GASMAS or Multiple-Scattering LIDAR).     

Gas moderation of positrons

A variety of low-energy positron experiments need an improved brilliance of the beam by means of a remoderator. Conventionally, a tungsten foil or single crystal is used as a remoderator in transmission or reflection geometry. We have developed a new remoderation unit which is based on inelastic positron scattering and the drift of positrons in nitrogen gas. In first measurements we succeeded in detecting fully thermalized positrons. High positron losses occurred at the entrance of the gas cell, and therefore the injection of positrons will be improved for next measurements.