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Open Journal of Physical Chemistry 2011年第3期1卷 61-69页

作者： Abdeslam Hassen Meniai Serge Laugier Hakim Madani Dominique Richon 不详

This paper focuses on a very important point which consists in evaluating experimental data prior to their use for chemical process designs. Hexafluoropropylene P, ρ, T data measured at 11 temperatures from 263 to 362 K and at pressures up to 10 MPa have been examined through a consistency test presented herein and based on the use of a methodology implying both neural networks and virial equation. Such a methodology appears as very powerful to identify erroneous data and could be conveniently handled for quick checks of databases previously to modeling through classical thermodynamic models and equations of state. As an application to liquid and vapor phase densities of hexafluoropropylene, a more reliable database is provided after removing out layer data.

关键词： Consistency Tests Hexafluoropropylene Neural Networks Vibrating Tube Densimeter virial Equation

Resultant gradient information, kinetic energy and molecular virial theorem

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Chemical Reports 2019年第1期1卷 22-35页

作者： Roman F. Nalewajski Department of Theoretical Chemistry Jagiellonian University Gronostajowa 2 30-387 Cracow Poland

Resultant gradient-information is introduced and applied to problems in chemical reactivity theory. This local measure of the structural information contained in (complex) wavefunctions of electronic states is related to the system overall kinetic energy combining the modulus (probability) and phase (current) contributions. The grand-ensemble representation of thermodynamic equilibria in open systems demonstrates the physical equivalence of the variational energetic and information principles. It is used and to relate the populational derivatives of ensemble-average functionals in both these representations, which represent reactivity criteria for diagnosing the charge-transfer (CT) phenomena. Their equivalence is demonstrated by using the in situ potential and hardness descriptors to predict the direction and optimum amount of CT. The virial theorem is generalized into thermodynamic quantities and used to extract the kinetic energy component from qualitative energy profiles in the bond-formation and (exo/endo)-ergic reactions. The role of electronic kinetic energy in such chemical processes is reexamined, the virial theorem implications for the Hammond postulate of reactivity theory are explored, and variations of the structural-information in chemical processes are addressed. The maximum thermodynamic information rule is formulated and "production" of the gradient-information in chemical reactions is addressed. The Hammond postulate is shown to be indexed by the geometric derivative of resultant gradient-information at transition-state complex.

关键词： bond formation chemical reactivity grand ensemble information theory resultant information virial theorem

Closed virial equations for hard parallel cubes andsquares

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Natural Science 2011年第7期3卷 622-632页

作者： Leslie V. Woodcock 不详

A correlation between maxima in virial coefficients (Bn), and “kissing” numbers for hard hyper-spheres up to dimension D = 5, indicates a virial equation and close-packing relationship. Known virial coefficients up to B7, both for hard parallel cubes and squares, indicate that the limiting differences Bn – Bn-1 behave similar to spheres and disks, in the respective expan-sions relative to maximum close packing. In all cases, the difference Bn – Bn-1 is approaching a negative constant with similar functional form in each dimen-sion. This observation enables closed-virial equa-tions-of-state for cubes and squares to be obtained. In both the 3D and 2D cases, the virial pressures begin to deviate from MD thermodynamic pressures at densities well below crystallization. These results consolidate the general conclusion, from previous papers on spheres and disks, that the Mayer cluster expansion cannot represent the thermodynamic fluid phases up to freezing as commonly assumed in statistical theories.

关键词： virial Equations Liquid Theory

A　Multi－Square－Well　Potential　Model　and　Its　Application　in　Calculating　the　Second　virial　Coefficient

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Journal of Harbin Institute of Technology(New Series) 1994年第2期1卷 15-20页

作者：苏志军严家曾向东尚德敏

ＡＭｕｌｔｉ－Ｓｑｕａｒｅ－ＷｅｌｌＰｏｔｅｎｔｉａｌＭｏｄｅｌａｎｄＩｔｓＡｐｐｌｉｃａｔｉｏｎｉｎＣａｌｃｕｌａｔｉｎｇｔｈｅＳｅｃｏｎｄＶｉｒｉａｌＣｏｅｆｆｉｃｉｅｎｔ￥（苏志军）（严家）（曾向东）（尚德敏）... 详细信息

ＡＭｕｌｔｉ－Ｓｑｕａｒｅ－ＷｅｌｌＰｏｔｅｎｔｉａｌＭｏｄｅｌａｎｄＩｔｓＡｐｐｌｉｃａｔｉｏｎｉｎＣａｌｃｕｌａｔｉｎｇｔｈｅＳｅｃｏｎｄＶｉｒｉａｌＣｏｅｆｆｉｃｉｅｎｔ￥（苏志军）（严家）（曾向东）（尚德敏）ＳＵＺｈｉｊｕｎ；ＹＡＮＪｉａｌｕ...

关键词： ss: Molecular potential square-well potential model second virial coefficient

物理学咬文嚼字之四十九 Vis et virial

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物理 2012年第8期41卷 546-548页

作者：曹则贤中国科学院物理研究所北京100190

维里定理中的virial是个力学量,不是人名.它源于vis viva中的***出现在众多物理概念中,virial theorem的一个重要应用结果是暗物质概念的提出.到了给virial找个合适的中文翻译的时候了.

关键词：物理学 virial virial 维里定理物理概念中文翻译 vis 力学量

不完全气体第二virial系数的论证及Van der waals方程中a和b的推算

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西安理工大学学报 1980年第3期 97-106页

作者：阮芙英陕西机械学院物理教研室

本文主要根据 Mayer 理论和巨正则系综的统计方法对不完全气体进行较精确的处理.在此理论中是假定分子间相互作用力都是近距离分子成对呈现的向心力。为求得不完全气体状态方程 PV=NKT(1+(B(T)/V)+(C(T)/V~2)+…)的 virial B(T)及 Van d... 详细信息

本文主要根据 Mayer 理论和巨正则系综的统计方法对不完全气体进行较精确的处理.在此理论中是假定分子间相互作用力都是近距离分子成对呈现的向心力。为求得不完全气体状态方程 PV=NKT(1+(B(T)/V)+(C(T)/V~2)+…)的 virial B(T)及 Van der Waals 方程中的修正数 a 和 b 应用了数学变换及群积分的方法,由此顺利得到了满意的结果。用此法较一般的统计方法所得结果既精密又简捷。

关键词：方程完全气体理想气体位型积分积分学单原子分子 virial Van der waals 第二维里系数 der

考虑流动摩擦和状态方程virial修正的Laval喷管湿蒸汽膨胀流动的理论解

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工程热物理学报 1987年第4期 317-322页

作者：黄跃蔡颐年西安交通大学

本文介绍了考虑汽流与喷管壁面之间的摩擦和用virial型状态方程描述水蒸汽热力性质的超音速膨胀湿蒸汽双相流动的求解方法及相应的计算程序,较之通常所用的将水蒸汽作为理想气体并且假设膨胀过程无摩擦的计算程序更加完善.用此程序对低... 详细信息

本文介绍了考虑汽流与喷管壁面之间的摩擦和用virial型状态方程描述水蒸汽热力性质的超音速膨胀湿蒸汽双相流动的求解方法及相应的计算程序,较之通常所用的将水蒸汽作为理想气体并且假设膨胀过程无摩擦的计算程序更加完善.用此程序对低压范围的Laval喷管流动进行了计算,所得结果与已有结果符合较好.

关键词：流动摩擦状态方程 P-V-T关系式 virial Laval 理论解

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一个推广virial定理的数学方法和应用

力学学报 1983年第6期 579-589页

作者：潘良儒中国科学院力学研究所

本文在提出广义Gauss定理的思路下,提出了广义Stokes定理和一个推广virial定理的新方法,后者应用于天体磁流体力学和引力平衡问题时得到的结果有:(1)气体具有运动时的平衡系统的判据,(2)磁场对气团形态的影响。应用于实验室等离子体平... 详细信息

本文在提出广义Gauss定理的思路下,提出了广义Stokes定理和一个推广virial定理的新方法,后者应用于天体磁流体力学和引力平衡问题时得到的结果有:(1)气体具有运动时的平衡系统的判据,(2)磁场对气团形态的影响。应用于实验室等离子体平衡问题时,其结果有:(1)包围在气体中孤立磁场的特性,(2)发现内包无力场必须外包一有力场,(3)无力场的形态,应用于Tokmak等离子体环时的结果有:(1)环的胖瘦对环表面磁压的影响,(2)两个外加磁场分量分别和气压、环的胖瘦,截面形态、环电流分布和逆磁或顺磁的平衡关系,搞清楚了外加磁场约束等离子体总体平衡的物理机制。

关键词：等离子体环 virial 数学方法定理磁场电磁场无力场无作用力磁场广义

EQUATIONS OF STATE FOR HARD-SPHERE CHAIN FLUIDS AND SQUARE-WELL CHAIN FLUIDS

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Chinese Journal of Chemical Engineering 1996年第2期4卷 4-12页

作者：刘洪来戎宗明胡英华东理工大学热动力研究实验室上海

Based on the statistical theory for chemical association,equations of state for hard-spherechain fluids(HSCFs)and square-well chain fluids(SWCFs)can be derived through the n-particlecavity correlation function(CCF)of the corresponding reference system,where n is the chain lengthor the number of segments of a chain *** reference system is a fluid composed of only cor-responding *** this work,the n-particle CCF is approximated by a product of effectivetwo-particle CCFs which accounts for correlations in nearest-neighbour and next-to-nearest-neighboursegment *** CCFs for SWCFs may be expressed by a product of the corresponding functionfor HSCFs and a perturbation term originated from the square-well attractive *** these ef-fective two-particle CCFs and perturbation terms are density *** dependence is determinedmainly by using computer-simulation *** obtained equations can excellently describecompressibility factors and second virial coefficients for

关键词： equation of state polymer solution polymer blend compressibility factor second virial coefficient statistical theory chemical association

VLW equation of state of detonation products

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Science China Chemistry 2009年第5期52卷 605-608页

作者： WU Xiong LONG XinPing HE Bi JIANG XiaoHua Xi’an Modern Chemistry Research Institute Xi’an 710065China China Academy of Engineering Physics Mianyang 621900China Institute of Chemical Materials CAEPMianyang 621900China

Based on the virial theory, we proposed VLW equation of state of detonation products (VLW EOS). Its basic theory and applications were described. The distinct features of the VLW EOS were:First, the detonation performance of the new high energy density materials could be predicted more reliably. Second, it had extensive application. The detonation parameters of both the condensed high energy density materials and the gaseous fuel air explosives could be calculated. Moreover, combustion performance of propellants could also be precisely calculated. The calculation results were satisfactory.

关键词： virial coefficients energetic materials equation of state detonation