具有ns^2,ns^2np^6和ns^2np^6nd^10构型的原子和离子抗磁 …

推广Ｋｉｒｋｗｏｏｄ关系式于最外层满壳层电子结构的原子和离子的等电子系列，得到原子和离子的抗磁化率与有效核电荷的简单关系式。并依此计算了原子和离子的抗磁化率，给出了某些阴离子的抗磁化率。     

电磁感应和磁介质的抗磁性

从电磁感应的基本定律出发,探讨了感生电场对磁介质原子中轨道电子的作用,对于抗磁质的抗磁性给出了明晰的解释;根据所得公式,以常见的抗磁质铜为例,估算出了磁化率.这一定量计算结果,在数量级上与一般物理学文献中所公认的数值吻合得很好.     

电磁感应和磁介质的抗磁性

从电磁感应的基本定律出发，探讨了感生电场对磁介质原子中轨道电子的作用，对于抗磁质的抗磁性给出了明晰的解释；根据所得公式，以常见的抗磁质铜为例，估算出了磁化率，这一定量计算结果，在数量级上与一般物理学文献中所公认的数值吻合得很好。     

用线形变分波函数计算双电子原子的抗磁性磁化率与极化率

原子的抗磁性磁化率与极化率是很多物理和化学问题的重要物理量。由于用实验测定有些困难,因而需要用理论计算——用原子的波函数来算出可靠的数值。计算结果的优劣与波函数的准确与否有关,有人用单电子波函数来计算双电子原子的抗磁性磁化率,得到的结果与实验符合较好。但由于双电子原子中两个1s电子有较强的关联作用,(1)式还不能反映这种强的关联作用。因而,有人使用了比较简单的双电子波函数     

关于离子晶体熔化和拉伸断裂时离子间距之间关系的探讨

从晶格势能曲线的特点出发,根据晶体拉伸断裂时的理论条件,计算了NaCl-型晶体拉伸断裂时的离子间距γi。发现拉伸断裂时的离子间距γi与从等压态方程计算得到的晶体熔化时的离子间距γm之间存在一个经验关系式,即γm=（0.838±0.013）γm。利用此简单的关系式可以预测未知晶体的熔化温度。     

Ba~(2 )在玻璃表面层中的扩散

本文应用离子探针 IMA 研究了在电场作用下 Ba~(2 )在玻璃表面层中的扩散,提出了对所得 IMA 数据的处理方法。推导出电场作用下二价阳离子的扩散系数与摩尔分数的关系式,此关系式所给结果与用 Boltzmann-Matanno 方法测得的 Ba~(2 )的扩散系数基本一致。     

亲电加成机理,立体特殊性和区域选择性的轨道控制规则(英文)

本文根据定性分子轨道理论,提出了适用于大多数亲电加成反应的普遍性理论规则,即以周期表四、五周期原子为亲电中心的加成,通常为桥型离子加成机理,具反式立体特殊性和非区域选择性。第一、二周期原子为加成中心者,通常为开放离子机理,本质上为非立体特殊性和区域选择性;三及六周期原子为中心者,易受+I及+M影响,而转化为开放离子的桥型离子机理和相应的易逆转的反式立体特殊性和易逆转的非区域选择性。     

N_2分子部分电子态的完全振动能谱和离解能的研究

借助最新创建的能精确计算双原子分子离解能的新解析表达式,结合孙卫国等建立的能正确获得某双原子分子/离子电子态的完全振动能谱的代数方法(AM),对N2分子的X1∑+g和B3∏g电子态的完全振动能谱和离解能进行了研究,获得了与实验值符合得很好的理论结果,同时为相关领域提供了可靠的高激发振动态的理论光谱数据。     

离子液体和微波在多组分缩合反应中的应用

以微波辅助、离子液体中的多组分缩合反应可以同时达到绿色无污染、原子经济性、快速高效几个目的。综述了近些年来微波和离子液体在多组分缩合反应中的应用。     

Li_2O-B_2O_3-ZrO_2系统玻璃的结构研究

用径向分布函数和红外光谱分析方法研究了Li_2O-B_2O_3-ZrO_2和Li_2O-B_2O_3等系统玻璃的结构。得出了Li_2O-B_2O_3-Z_rO_2系统玻璃中的Zr~(4+)离子影响碱硼酸盐玻璃的网络结构。随着Z O_2含量的增加BO_3三角体转变为BO_4四面体,并形成含BO_4四面体较多的硼酸盐基团。在含Z O_2为10mol％的锂硼酸盐玻璃的RDF曲线中,第一峰的位置r_1=1.54A可能是~3B-φ(φ表示桥氧),~4B-φ和Z_r-O原子对距离的贡献;第二峰的位置r_2=2.28A是O—O;Li O和Z_r-O原子对距离的贡献;第三峰的位置r_3=3.30A是Zr-Z_r原子对距离。玻璃中的Z_r~(4+)离子作为网络修饰体以6配位状态填充于硼酸盐基因空隙中。     

抗肿瘤多酸[Mo7O24]6-还原位置的理论研究

用密度泛涵理论的离散变分方法（DFT-DVM），对[Mo7O24]^6-及其光还原产物[Mo7O23(OH)]^6-的电子结构进行了系统的计算，结果表明：[Mo7O24]^6-中处于中心位置的Mo原子被还原的可能性最大，这与T.Yamase所认为的位置不尽相同。     

无机含氧酸分子的MNDO方法计算

通过对１５个无机含氧酸分子的ＭＮＤＯ方法计算，多角度分析、讨论了非羟基氧原子的电子密度Ｐｅ（Ｏ）、中心原子的离子势Ｏ，作为酸强度判据的适用性，并展望了用酸分子及其１价负离子的生成热之差来计算无机酸强度的可能性①．     

MgCu_2型laves相的微观熔化模型与熔化的电子理论分析

本文基于固体与分子经验电子理论,确定了八种laves相的价电子结构,提出了MgCu_2型laves相的熔化条件是A—A键断,并从理论上给予了解释,应用熔点的电子理论对MgCu_2型laves相的熔点进行了计算,理论值与实际值的误差在10％以内,使原子杂化态的高温效应观点的正确性在化合物中得到了新的证明。     

First-principles investigation on structural and electrochemical properties of NaCoO_2 for rechargeable Na-ion batteries

NaxCoO2 is a commonly used cathode material for sodium ion batteries because of its easy synthesis, high reversible capacity and good cyclability. The structural and electrochemical properties of NaxCoO2 during sodium ion insertion/extraction process are studied based on first principles calculations. The calculation results of crystal structure parameters and average intercalation voltage are in good agreement with experiment data. Through calculation of the geometric structure and charge transfer in charging and discharging processes of NaxCoO2, it is found that the oxygen atom surrounding Co of the CoO6 octahedral screens the coulomb potential produced by sodium vacancy in NaxCoO2, and the charge is removed from the entire Co-O layer instead of the Co atom adjacent to sodium vacancy when sodium ions are extracted from the Na CoO2 lattice. Thus, during the insertion/extraction of sodium ion from Na CoO2, the CoO6 octahedral structure undergoes small lattice distortion, which makes the local structure quite stable and is beneficial to the cycling stability of the material for the application of sodium ion batteries.     

Degradation Behavior of Ti-6Al-4V Alloys for Dental Applications in Acidic Artificial Saliva Containing Fluoride Ion

The aim of this work was to study the degradation behavior of Ti-6Al-4V alloys for dental applications in acidic artificial saliva with fluoride ion using electrochemical techniques, optical microscopy, scanning electron microscopy(SEM), and energy dispersive spectrometry(EDS). The experimental results showed that fluoride ion had significant influence on the degradation of Ti-6Al-4V alloys, and there was an obvious critical concentration of fluoride ion(about 0.1wt%). With increasing fluoride ion concentration, the corrosion potential(Ecorr) of alloys moved toward negative and the impedance of alloys decreased, meanwhile, noticeable transformation from minimum corrosion to severe pitting corrosion was observed on alloys surface following the dissolution of TiO_2 passive films, leading to the decrease of the corrosion resistance of alloys. The electrochemical dissolution of TiO_2 passive films involved a nucleophilic attack of fluoride atom to the titanium atom of TiO_2. In addition, Ca~(2+)and Na~+ in acidic saliva may involve the surface reactions and make the reactions more complex.     

First-principles study on adsorption of Au atom on hydroxylated SiO<Subscript>2</Subscript> surface

Adsorption of single gold (Au) atom at three kinds of sites (hollow, bridge and top) on the hydroxylated β-cristobalite SiO2 (1 1 1) surface was studied using the first-principles calculations with general gradient approximation (GGA). The results of adsorption energies and density of electronic states (DOS) suggest that the hollow and bridge sites have the basically equal capability of binding Au, while the ability of the Top site is weaker. Two new energy levels emerge after the adsorption at all sites; i...     

纤锌矿AlN中反位和间隙点缺陷电子结构的最大局域化Wannier函数方法研究

结合第一性原理计算方法,利用最大局域化Wannier函数方法研究了纤锌矿AlN中反位和间隙点缺陷引起的电子结构变化及成键性质.研究发现:在N反位缺陷结构中,反位N原子只与[0001]方向上最近邻的N原子成键,未成键的孤对电子局域在反位N原子及其余最近邻的3个N原子附近;在Al反位缺陷中,反位Al原子与垂直于[0001]方向的底面上3个最近邻Al原子成键.研究同时发现:在反位和间隙缺陷中,N间隙对电子结构影响最小,间隙N原子与下方最近邻的3个Al原子成键;尽管Al间隙对电子结构影响最大,但间隙Al原子并不与周围原子成键.无疑,相比于传统的电子结构分析方法,最大局域化Wannier函数方法更加直观便捷,能给出清晰的物理图景.     

Magnetic levitation using diamagnetism: Mechanism,applications and prospects

As a typical contact-free manipulation technique that removes friction and contamination risk, levitation has gradually become a preferred candidate for various applications. Magnetic levitation using diamagnetism, beyond Earnshaw's theorem, is a kind of passive stable levitation that can be achieved at normal temperatures with no energy input. Appealingly, most seemingly nonmagnetic materials can be levitated in a magnetic field and can stabilize free levitation of magnetic materials. This review focuses on the fundamental principles of magnetic levitation using diamagnetism, with emphasis on its burgeoning applications.The theoretical basis associated with the magnetic levitation using diamagnetism is discussed by elucidating the characteristics of diamagnetic materials, and the key levitation mechanisms are clarified. Afterwards, state-of-the-art applications in various aspects, including sensing and measurement, actuating and micromanipulation, energy harvesting and magnetic gravity compensation, are summarized and compared. Finally, the review concludes with a brief outlook on future perspectives.     

Sm掺杂La_2Mo_2O_9的合成及其导电性

用固相反应法合成了La2-xSmxMo2O9(x=0~2)。室温XRD测试结果表明,在掺Sm计量x≥0.9时,出现杂质相的衍射峰;x≤0.85时,晶胞参数随Sm掺杂计量增加而线性降低。用直流四电极法和离子阻塞法在723~1 173 K温度范围测定了合成试样的电导率,结果表明电子电导率和电导率均随Sm掺杂量增大而降低,掺Sm增大了电导活化能和电子电导活化能。