为什么水在金属表面的吸附构型是倾斜的——水在铜、铝表面吸附的量子化学计算

用量子化学从头算方法,分别以原子簇Ｃｕ５、Ａｌ４、Ａｌ１０模拟Ｃｕ（１００）和Ａｌ（１１１）表面,在不同基组水平上,计算了水在两种金属表面上倾斜吸附的热能面,结果表明：当计算基组中不含氧原子的ｄ轨道时,得到水分子在金属垂直吸附的构型,这与实验结果不符;当水中氧原子加极化函数时,水分子倾斜吸附时能量较低,得到与实验相符的吸附构型。这说明水中氧原子ｄ轨道在计算中起着关键作用,在成键过程中有着重要影响。     

Cl+F2→ClF+F和F+ClF′→ClF+F′反应机理的密度泛函理论研究

用密度泛函理论（ＤＦＴ）Ｂ３ＬＹＰ方法,在６－３３１Ｇ＊基组下,计算研究了反应Ｃｌ＋Ｆ２→ＣｌＦ＋Ｆ和对称反应Ｆ＋ＣｌＦ’→ＣｌＦ＋Ｆ’的机理。求得前者的过渡态为三角形,活化能为１５．５７ｋＪ·ｍｏｌ＾－１;后者的过渡态为线形和三角形,活化能分别为１１．５２和１９６．２５ｋＪ·ｍｏｌ＾－１。结果均经过振动分析和ＩＲＣ计算验证。     

分子转动惯量与正烷烃熔沸点的预测

在分子转动模型基础上,以半经验分子轨道（ＡＭ１）方法计算分子的转动惯量及其它结构参数,获得１５个正烷烃的沸点和熔点的多元线性回归方程。其中正烷烃的沸点与短轴转动惯量（ｃ）和碳原子数（ｎ）相关（ｂｐ＝－１４７．－０．０１１８９ｃ＋３６．１７ｎ,Ｒ＝０．９９８５,ＳＤ＝６．９７）,而熔点与分子的长轴转动惯量（ａ）、短轴转动惯量（ｂ,ｃ）及重定向能（Ｅ）相关（ｍｐ＝－２６０．３＋１５．７０ａ＋１９．７４     

Study of Spectroscopic Properties of Yb-doped Calcium Fluorapatite

The spectroscopic performance of Yb-doped calcium fluorapatite (Yb:FAP) was assessed by measuring polarization absorption spectra, polarization emission spectra and fluorescence lifetime. The emission cross section has been evaluated using the absorption cross section and principle of reciprocity. The π polarization absorption and emission cross sections of Yb3+ in FAP are found to be substantially larger than those of other Yb-doped media. Favorable spectroscopic parameters show that Yb:FAP crystal is more desirable for many diode-pumped solid state laser application with low- and medium-power in the near future.     

Phase diagrams of noisy traffic states in the presence of a bottleneck

The traffic states are investigated for the noisy traffic flow in the presence of a bottleneck under the open boundary condition. The phase diagrams of the different kinds of congested traffic are presented for different values of sensitivity (the inverse of delay time). It is shown that the five different types of traffic states appear below the critical point: the free traffic with a pinned localized cluster, the weak standing shock, the moving localized cluster, the oscillatory congested traffic, and the strong standing shock. Above the critical point, the moving localized cluster and oscillatory congested traffic do not occur. Also, in the traffic flow without noise, the moving localized cluster and oscillatory congested traffic do not appear.     

用伏安法测绘二极管伏安特性的研究

本提出用伏安法测绘二极管伏安特性曲线的一种电路新接法,用该接法测量时,不需修正即可完全消除电表内阻的影响。     

如何给工科大学生讲量子力学

本文论述在量子力学中引入Ｗｉｇｎｅｒ准概率分布函数,通过与统计物理类比,为理解量子力学打开了方便之门．     

二元化合物内聚能的线性化缀加平面波能带方法的计算研究

采用线性化缀加平面波能带方法,研究了典型二元化合物NiAl,SiC,GaAs,MgS和NaCl的晶体总能和内聚能,着重考查了二元素Muffin-tin半径的选取对各晶体总能和内聚能的影响。计算结果表明,对NiAl合金,Muffin-tin半径的变动几乎不改变其晶体总能;组元原子的共价键半径可以作为共价键晶体如SiC和GaAs的Muffin-tin半径;但是,元素的离子半径不适合于作为具有较强离子键合的离子性晶体如MgS和NaCl的Muffin-tin半径,因为这时阳离子有较多的芯电子溢出Muffin-tin球。通过选取适当的Muffin-tin半径,对如上化合物计算得到的内聚能与实验结果符合。     

Gaussian Limiting Behavior of the Rescaled Solution to the Linear Korteweg–de Vries Equation with Random Initial Conditions

We analyze the asymptotic behavior of the rescaled solution to the linear Korteweg–de Vries equation when the initial conditions are supposed to be random and weakly dependent. By means of the method of moments we prove the Gaussianity of the limiting process and we present its correlation function. The same technique is applied to the analysis of another third-order heat-type equation.