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基于原子-分子理论的二元合金熔体热力学计算 被引量:2
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作者 段生朝 郭汉杰 +5 位作者 郭靖 鲁浩 石骁 杨文晟 刘帅 于梦曦 《有色金属科学与工程》 CAS 2017年第3期7-15,共9页
分别使用Miedema、MIVM、NRTL、Wilson二元合金系热力学模型及Fact Sage热力学软件计算Bi-Pb、Bi-Sn、Cd-Pb、Pb-Sn 4个二元合金系的活度值,并与实验值进行比较.结果表明:Miedema、MIVM、NRTL、Wilson模型计算不同体系活度的效果不同,... 分别使用Miedema、MIVM、NRTL、Wilson二元合金系热力学模型及Fact Sage热力学软件计算Bi-Pb、Bi-Sn、Cd-Pb、Pb-Sn 4个二元合金系的活度值,并与实验值进行比较.结果表明:Miedema、MIVM、NRTL、Wilson模型计算不同体系活度的效果不同,每种模型都有其适用的体系.而Fact Sage热力学软件计算的活度均与实验值吻合较好,文中使用Fact Sage分别计算Bi-Pb、Bi-Sn、Cd-Pb、Pb-Sn 4个二元系不同温度下的活度值.同时利用原子-分子理论计算Bi-Pb二元系质量作用浓度,给出生成金属间化合物Bi Pb反应的标准吉布斯自由能的表达式. 展开更多
关键词 二元合金 FactSage 原子-分子理论 热力学 活度
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近代化学史上的“半个原子”问题 被引量:1
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作者 张玉春 《洛阳师范学院学报》 2004年第2期116-118,共3页
道尔顿的原子论是近代化学史上的一项划时代的成就 ,但是它存在着一个自身不能克服的内在矛盾 ,即道尔顿把化合物的“原子”称为“复杂原子” .这一矛盾的外化 ,导致产生了“半个原子”的问题 .为了解决“半个原子”的矛盾问题 ,阿佛加... 道尔顿的原子论是近代化学史上的一项划时代的成就 ,但是它存在着一个自身不能克服的内在矛盾 ,即道尔顿把化合物的“原子”称为“复杂原子” .这一矛盾的外化 ,导致产生了“半个原子”的问题 .为了解决“半个原子”的矛盾问题 ,阿佛加德罗在盖·吕萨克的实验基础上 ,进行了科学合理的推论 ,引入了分子概念 ,提出了分子假说 ,初步解决了“半个原子”的矛盾问题 .在此基础上 ,坎尼扎罗完成了科学的“原子 -分子”理论体系 ,最终完善地解决了“半个原子”矛盾问题 .本文通过对“半个原子”矛盾问题的形成、提出和解决过程的历史考察 ,总结出了科学发展的几点规律性的结论 . 展开更多
关键词 原子 分子假说 原子-分子理论
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“半个原子”矛盾的形成与解决
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作者 张玉春 《枣庄师范专科学校学报》 2003年第5期74-78,共5页
在近代化学史上曾经产生过“半个原子”的矛盾,它的形成与解决构成了近代化学发展的一条主线。透过近代化学发展的历史不难发现,道尔顿原子论是近代化学史上的一项划时代的成就,但是它存在着一个自身不能克服的内在矛盾,即道尔顿把化合... 在近代化学史上曾经产生过“半个原子”的矛盾,它的形成与解决构成了近代化学发展的一条主线。透过近代化学发展的历史不难发现,道尔顿原子论是近代化学史上的一项划时代的成就,但是它存在着一个自身不能克服的内在矛盾,即道尔顿把化合物的“原子”称为“复杂原子”。道尔顿原子论之理论自身这一矛盾的外化,导致产生了“半个原子”的矛盾。为了解决“半个原子”的矛盾,阿佛加德罗在盖·吕萨克的实验基础上,进行了科学合理的推论,引入了分子概念,提出了分子假说,初步解决了“半个原子”的矛盾。在此基础上,坎尼扎罗完成了科学的“原子-分子”理论体系,最终完善地解决了“半个原子”的矛盾。这个过程再现了唯物辩证法的“扬弃观”、“内因论”和“外因论”的思想,依次具体体现为科学理论的曲折发展律、内在矛盾动力律和内在矛盾外化律。客观地考证分析“半个原子”矛盾的形成和解决的过程,并全面地总结科学理论的发展规律,对于深刻地理解科学的“原子-分子”理论,对于全面地理解唯物辩证法的基本规律,对于在中学化学教育全面培养学生的科学素质和人文素质等,具有重大的理论价值和巨大的现实意义。 展开更多
关键词 “半个原子”的矛盾 原子 分子假说 原子-分子理论 近代化学史 科学发展规律
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Non-additivity of Methyl Group in the Single-electron Lithium Bond of H3C… Li-H Complex
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作者 李志锋 施小宁 +2 位作者 刘艳芝 唐慧安 张俊彦 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期303-309,340,共8页
The non-additivity of the methyl groups in the single-electron lithium bond was investigated using ab initio calculations at the B3LYP/6-311++G** and UMP2/6-311++G** levels. The strength of the interaction in ... The non-additivity of the methyl groups in the single-electron lithium bond was investigated using ab initio calculations at the B3LYP/6-311++G** and UMP2/6-311++G** levels. The strength of the interaction in the H3C… LiH, H3CH2C… LiH, (H3C)2HC… LiH, and u v (H3C)3C… LiH complexes was analyzed in term of the geometries, energies, frequency shifts, stabilization energies, charges, and topological parameters. It is shown that (H3C)3C radical with LiH forms the strongest single-electron lithium bond, followed by (H3C)2HC radical, then H3CH2C radical, and H3C radical forms the weakest single-electron lithium bond. A positive non-additivity is present among methyl groups. Natural bond orbital and atoms in molecules analyses were used to estimate such conclusions. Furthermore, there are few linear/nonlinear relationships in the system and the interaction mode of single-electron Li- bond is different from the single-electron H-bond and single-electron halogen bond. 展开更多
关键词 Single-electron lithium bond Single-electron hydrogen bond Single-electronhalogen bond MP2 Natural bond orbital Atoms in molecules
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Determination of thermodynamic properties in full composition range of Ti-Al binary melts based on atom and molecule coexistence theory 被引量:1
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作者 Sheng-chao DUAN Xiao SHI +2 位作者 Wen-sheng YANG Han-jie GUO Jing GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第6期1256-1264,共9页
The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for ca... The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for calculating mass action concentration N_i of structural units in Ti-Al system based on the atom and molecule coexistence theory(AMCT). Temperature dependence of the activity coefficients of Ti and Al in natural logarithmic form in the infinitely dilute solution(0x_(Ti)0.01) of Ti-Al binary melts was also determined from the calculated activity coefficients of Ti and Al at temperatures of 1973, 2073, 2173, and 2273 K. The standard molar Gibbs free energy change of dissolving pure liquid element i(l) for forming 1%(mass fraction) element i in Ti-Al binary melts further was deduced. With the aid of this model, meanwhile, the determined excess thermodynamic properties, such as the excess molar mixing Gibbs free energy/entropy/enthalpy were also calculated. 展开更多
关键词 Ti-Al binary system Ti Al activity coefficient thermodynamic model mass action concentration atom and molecule coexistence theory
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Hydrogen Bonding Character Between the Glycine and BF4^-
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作者 Qin He Jing Yang Xiang-jun Meng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第5期517-522,I0002,共7页
The hydrogen bonding character between the BF4- and glycine was theoretically studied at the level of B3LYP/6-31+G^*, single point energies were performed at the level of B3LYP/6-311++G^**. The relevant geometri... The hydrogen bonding character between the BF4- and glycine was theoretically studied at the level of B3LYP/6-31+G^*, single point energies were performed at the level of B3LYP/6-311++G^**. The relevant geometrical characteristics, energy properties, as well as the characters of the intramolecular hydrogen bonds have been studied. Atoms in molecule theory topological analysis indicated the (3,-1) critical points for hydrogen bonds. In addition, the electron density and Laplacian were in the range suggested for the hydrogen bonds. Especially, the changes of atomic charge, hydrogen upon hydrogen bonds formation dipole moment, enegry as well as volume of the were systemitically discussed. 展开更多
关键词 B3LYP BF4^- Glycine hydrogen bond Atoms in molecule theory
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爱因斯坦与布朗运动 被引量:7
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作者 蒋长荣 王骁勇 刘树勇 《首都师范大学学报(自然科学版)》 2005年第3期28-32,共5页
简要介绍了原子-分子理论的发展过程、爱因斯坦对于布朗运动的理论研究和佩兰对爱因斯坦布朗运动理论的验证.
关键词 原子-分子理论 爱因斯坦 布朗运动 佩兰
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Splitting of Spectra in Anharmonic Oscillators Described by Kratzer Potential Function
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作者 Irina Petreska Trifce Sandev +1 位作者 Gjorgji Ivanovski Ljupo Pejov 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期138-142,共5页
A perturbation theory model that describes splitting of the spectra in highly symmetrical molecular species in electrostatic field is proposed. An anahrmonie model of a two-dimensional oscillator having Kratzer potent... A perturbation theory model that describes splitting of the spectra in highly symmetrical molecular species in electrostatic field is proposed. An anahrmonie model of a two-dimensional oscillator having Kratzer potential energy function is used to model the molecular species and to represent the unperturbed system. A selection rule for the radial quantum number of the oscillator is derived. The eigenfunctions of a two-dimensional anharmonic oscillator in cylindrical coordinates are used for the matrix elements representing the probability for energy transitions in dipole approximation to be calculated. Several forms of perturbation operators are proposed to model the interaction between the polyatomic molecular species and an electrostatic field. It is found that the degeneracy is removed in the presence of the electric field and spectral splitting occurs. Anharmonic approximation for the unperturbed system is more accurate and reliable representation of a reaJ polyatomic molecular species. 展开更多
关键词 two-dimensional anharmonic oscillator Kratzer potential DEGENERACY selection rules PERTURBATION
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Formation Mechanism and Binding Energy for Regular Octahedral Structure of Li_6 Cluster
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作者 ZHAO Yan-Ping LI Ping GOU Qing-Quan LIU Wei-Na 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1407-1410,共4页
The formation mechanism for the regular octahedral structure of Liscluster is proposed. The curve of the total energy versus the separation R between any two neighboring nuclei has been calculated by using the method ... The formation mechanism for the regular octahedral structure of Liscluster is proposed. The curve of the total energy versus the separation R between any two neighboring nuclei has been calculated by using the method of Gou's modified arrangement channel quantum mechanics (MACQM). The result shows that the curve has a minimal energy of -44.736 89 a.u. at R = 5.07a0. When R approaches infinity, the total energy of six lithium atoms has the value of -44.568 17 a.u. So the binding energy of Li6 with respect to six lithium atoms is 0.1687 a.u. Therefore, the binding energy per atom for Li6 is 0.028 12 a.u., or 0.7637 eV, which is greater than the binding energy per atom of 0.453 eV for Li2 and the binding energy per atom of 0.494 eV for Li3 calculated in our previous work. This means that the Li6 cluster may be formed in a regular octahedral structure with a greater binding energy. 展开更多
关键词 Li6 cluster formation mechanism binding energy
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On the Bonding Nature of Noble Gas Compounds MRg^(+) and MRgF(M=Co,Rh,Ir;Rg=Ar,Kr,Xe)
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作者 Si-yuan Xian Di-hao Tan An-yong Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第3期297-308,I0039-I0043,I0047,共18页
The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and therm... The structure and stability of the compounds MRg^(+)and MRg F(Rg=Ar,Kr,and Xe;M=Co,Rh,and Ir)were investigated using the B3 LYP,MP2,MP4(SDQ)and CCSD(T)methods.We reported the geometry,vibrational frequencies and thermodynamics properties of these compounds.A series of theoretical methods on the basis of wavefunction analysis,including natural bond orbitals,atoms in molecules,electron localization function,and energy decomposition analysis,were performed to explore bonding nature of the M-Rg and Rg-F bonds.These bonds are mainly noncovalent,the metal weakly interacts with Rg in MRg^(+),but their interaction is much stronger in MRg F.The neutral molecule MRg F can be well described by the Lewis structure[MRg]^(+)F^(-). 展开更多
关键词 Rare gases CO RH IR Bond nature Natural bond orbitals Atom in molecules analyses Electron localization function analyses
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A Note on Normal Forms of Quantum States and Separability
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作者 LI Ming FEI Shao-Ming WANG Zhi-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1307-1311,共5页
We study the normal form of multipartite density matrices.It is shown that the correlation matrix(CM)separability criterion can be improved from the normal form we obtained under filtering transformations.Based on CMc... We study the normal form of multipartite density matrices.It is shown that the correlation matrix(CM)separability criterion can be improved from the normal form we obtained under filtering transformations.Based on CMcriterion the entanglement witness is further constructed in terms of local orthogonal observables for both bipartite andmultipartite systems. 展开更多
关键词 separable state entanglement witness
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铝热法制备钒铝合金热力学及动力学研究 被引量:3
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作者 段生朝 王竹青 +4 位作者 郭汉杰 郭靖 石骁 刘帅 于梦曦 《钢铁钒钛》 CAS 北大核心 2017年第6期47-54,共8页
基于原子-分子理论建立了计算Al-V二元合金系结构单元质量作用浓度的热力学模型。利用文献报道的2 000、2 073、2 173、2 273 K下Al-V二元系的活度计算了生成Al8V5、Al4V反应的平衡常数,并进一步得到其摩尔标准吉布斯自由能的表达式。... 基于原子-分子理论建立了计算Al-V二元合金系结构单元质量作用浓度的热力学模型。利用文献报道的2 000、2 073、2 173、2 273 K下Al-V二元系的活度计算了生成Al8V5、Al4V反应的平衡常数,并进一步得到其摩尔标准吉布斯自由能的表达式。同时采用TG-DSC热重同步热试验分析的方法,研究了不同升温速率下,铝热法合成钒铝合金反应机理及化学反应动力学。结果发现温度在660~690℃时,差示扫描量热曲线各出现一个吸热、放热峰,说明反应机理已发生改变。然后分别运用Kissinger法、Kissinger-Crane法求解铝热反应动力学参数,建立动力学方程,通过动力学计算得到表观活化能E=448.96 k J/mol,频率因子A=1.98×10^(29)m/s,反应级数n=0.83。 展开更多
关键词 钒铝合金 铝热法 原子-分子理论 热力学 差示扫描量热 动力学
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Generalized Morrey spaces and trace operator 被引量:6
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作者 NAKAMURA Shohei NOI Takahiro SAWANO Yoshihiro 《Science China Mathematics》 SCIE CSCD 2016年第2期281-336,共56页
The theory of generalized Besov-Morrey spaces and generalized Triebel-Lizorkin-Morrey spaces is developed. Generalized Morrey spaces, which Mizuhara and Nakai proposed, are equipped with a parameter and a function. Th... The theory of generalized Besov-Morrey spaces and generalized Triebel-Lizorkin-Morrey spaces is developed. Generalized Morrey spaces, which Mizuhara and Nakai proposed, are equipped with a parameter and a function. The trace property is one of the main focuses of the present paper, which will clarify the role of the parameter of generalized Morrey spaces. The quarkonial decomposition is obtained as an application of the atomic decomposition. In the end, the relation between the function spaces dealt in the present paper and the foregoing researches is discussed. 展开更多
关键词 Morrey space trace operator DECOMPOSITION
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Manipulating Photoelectron Distributions for Rare Gas Atoms Ionized with Polarized Femtosecond Laser Pulses
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作者 李小刚 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第6期1053-1058,共6页
Above-threshold ionizations of rare gas atoms excited by polarized femtosecond laser pulses are investigated.The photoelectron momentum spectra are obtained applying the strong-field approximation(SFA) theory.It is fo... Above-threshold ionizations of rare gas atoms excited by polarized femtosecond laser pulses are investigated.The photoelectron momentum spectra are obtained applying the strong-field approximation(SFA) theory.It is found that,distribution of the emitted photoelectrons varies with different polarizations of laser pulses.We have interpreted the relationship between the observed distribution and the laser polarization taking advantage of tunneling ionization theory and simple-man model.The polarization sensitivity indicates that one can easily manipulate the photoelectron distribution by controlling the polarization of the exciting pulse. 展开更多
关键词 above-threshold ionization femtosecond laser strong-field approximation
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Structural and Interaction Properties of Porphyrin Layers — A Quantum Chemical Study
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作者 G.Praveena A.Abiram 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第5期625-634,共10页
This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used ... This paper is proposed to understand the interaction of porphyrin layers with diatomic molecules interacting at their interior regions by applying ab initio and density functional theory (DFT) methods. We have used NO, GO, and O2 diatomic molecules to interact with the porphyrin layers. The most common Fe-centered metalloporphyrin structure with tetra-pyrrlic rings having N4 core is chosen for the study. The optimization of Porphyrin-Porphyrin (PI-PII) and Porphyrin-Diatomic molecule-Porphyrin (P1-AB-P11) (AB = NO, CO, and 02) complexes are performed using HF method. In order to understand the planarity and appropriate stacking size of porphyrins and also to infer the separation of diatomic molecules between porphyrin layers the behavior of PI-AB-PH complexes (where AB = NO, CO, and 02) are analyzed using structural properties and molecular electrostatic potentials (MEP). The MEPs are caiculated using hybrid exchange correlation functional B3PW91 of DFT Mong with 6-31+G basis set for the PI-PH and PI-AB-Pzz complexes obtained from HF method. 展开更多
关键词 PORPHYRIN ab initio density functional theory diatomic molecules molecular storage
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Calculation of Excited States of He Atoms in a Strong Magnetic Field
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作者 赵力波 B.C.Saha 杜孟利 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第6期1059-1065,共7页
A recently developed B-spline algorithm is extended and utilized to calculate excited states of He atoms in the presence of strong magnetic fields.Binding energies are presented for He in the five excited atomic state... A recently developed B-spline algorithm is extended and utilized to calculate excited states of He atoms in the presence of strong magnetic fields.Binding energies are presented for He in the five excited atomic states 210-+,110-,210-,11(-1)+,and 2 1(1) + with magnetic field strength ranging from 0.0001 to 10 a.u.The obtained energies are compared with available theoretical data,and found to be in good agreement.We investigate influence of magnetic fields on atomic structures of multielectron atoms,and illustrate that how electron probability density distributions change with increasing magnetic field strength.The current approach is directly applicable to simulations of discrete spectra for He atoms in the atmospheres of magnetized white dwarf stars. 展开更多
关键词 He atom magnetic field B-spline basis
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