Molecule opacity study on low-lying states of CS

CS molecule, which plays a key role in atmospheric and astrophysical circumstances, has drawn great attention for long time. Owing to its large state density, the detailed information of the electronic structure of CS is still lacking. In this work, the high-level MRCI+Q method is used to compute the potential energy curves, dipole moments and transition dipole moments of singlet and triplet states correlated with the lowest dissociation limit of CS, based on which high accurate vibration—rotation levels and spectroscopic constants of bound states are evaluated. The opacity of CS relevant to atmospheric circumstance is computed at a pressure of 100 atms for different temperatures. With the increase of temperature, band systems from different transitions mingle with each other, and band boundaries become blurred, which are originated from the increased population on vibrational excited states and electronic excited states at high temperature.     

Debye-screening effect on electron-impact excitation of helium-like Al11+ and Fe24+ ions

Debye-screening effects on the electron-impact excitation (EIE) processes for the dipole-allowed transition 1s$^{2}$ $^{1}{\rm S} \to 1$s2p $^{1}$P in He-like Al$^{11+}$ and Fe$^{24+}$ ions are investigated using the fully relativistic distorted-wave methods with the-Hückel (DH) model potential. Debye-screening effects on the continuum-bound (CB) interaction and target ion are discussed, both of which result in reduction of EIE cross sections. This reduction due to screening on the CB interaction is dominant. The non-spherical and spherical DH potentials are adopted for considering the screening effect on the CB interaction. It is found that the spherical DH potential could significantly overestimate the influence of plasma screening on EIE cross sections for multielectron He-like ions.     

PCl3水解反应机理的理论研究

用密度泛函理论对PCl3水解反应机理进行了研究.优化了反应物、产物、中间体及过渡态的几何构型,通过频率计算和内禀反应坐标分析对过渡态结构及连接性进行了验证,对反应物、产物、中间体及过渡态的总能量进行了零点能校正,得到了各步水解反应的活化能.研究表明,PCl3同时发生亲电和亲核水解反应机理更易进行.     

测氡在滑坡研究中的应用

测氡是一种放射性地球物理方法,利用滑坡体与其周边岩土体的结构差异,应用测氡可对滑坡进行勘探,对滑坡的结构特征进行研究,达到节约投资,缩短勘探时间的目的,并可与地质分析相互验证,为工程应用提供依据。     

台湾桤木根叶养分内循环对施肥的响应

对比分析了施肥与未施肥退耕地7年生台湾桤木树叶和细根中N、P、K、Ca、Mg 5种元素内循环差异。结果发现：生活叶和落叶,活细根和死细根中各养分含量和5种元素总养分含量均为树叶〉极细根〉细根;树叶和细根都存在养分内循环,但树叶内循环率高于细根。各养分元素在树叶和细根中的内循环率并不一致,三大元素中K内循环率最高,N次之,P最低;Mg的内循环率较低,而Ca则表现为富集。施肥与树叶和细根中养分变化显著相关（P〈0.01）,施肥后树叶和细根中N,K含量和总养分含量增加,而P、Ca、Mg的含量减少;施肥与树叶养分内循环率变化显著相关（P〈0.01）,与细根养分内循环率变化中度相关,而与极细根养分内循环率变化不相关。     

一维多孔Fe-B合金纳米结构的制备及其磁性质

在十六烷基三甲基溴化铵(CTAB)的水溶液中,用NaBH₄还原FeCl₃,在反应过程中施加外部磁场,制得了一维多孔Fe-B合金纳米结构。研究表明,外部磁场对一维纳米结构的形成有重要影响,当不加外部磁场时得到的是离散的球形纳米粒子;外部磁场还影响Fe-B纳米粒子的晶体结构：外部磁场存在下得到的是无定形Fe-B合金,而不加外部磁场时则得到多晶Fe-B合金。CTAB对多孔的形成起到关键的作用,当不加CTAB时得到了实心球状纳米粒子。初步讨论了这种一维孔状Fe-B合金纳米结构的形成机理。用XRD、ICP-AES、TEM对样品进行了表征,测定了它们的磁性质。结果表明,在施加不同磁场强度条件下制得的样品具有不同的饱和磁化强度和矫顽力。     

A first-principles study of the magnetic properties in boron-doped ZnO

First-principles calculations based on density functional theory are performed to study the origin of ferromagnetism in boron-doped ZnO. It is found that boron atoms tend to reside at Zn sites. The induced Zn vacancy is a key factor for ferromagnetism in Zn1-xBxO (0相似文献   

Magnetic properties of a Pt/Co2FeAl/MgO structure with perpendicular magnetic anisotropy

Microstructures and magnetic properties of Ta/Pt/Co 2 FeAl（CFA）/MgO multilayers are studied to understand perpendicular magnetic anisotropy（PMA） of half-metallic full-Heusler alloy films.PMA is realized in a 2.5-nm CFA film with B2-ordered structure observed by a high resolution transmission electron microscope.It is demonstrated that a high quality interface between the ferromagnetic layer and oxide layer is not essential for PMA.The conversions between in-plane anisotropy and PMA are investigated to study the dependence of magnetic moment on temperature.At the intersection points,the decreasing slope of the saturation magnetization（M s） changes because of the conversions.The dependence of M s on the annealing temperature and MgO thickness is also studied.     

19-失碳-1α, 25-二羟基维生素D~3A环合成子的合成

报道以价廉、易得的D-(-)-奎尼酸为手性源,经9步反应,有效地合成光学活性的19-失碳-1α,25-二羟基维生素D~3A环合成子4的合成方法。     

NaK低激发态光谱性质和辐射寿命的从头算

本文对NaK的电子结构做了高级从头算. 计算了与三个最低解离极限相关的10个?-S态的势能曲线. 基于计算的势能曲线,得到了束缚?-S态的光谱常数,与实验结果吻合较好. 用半经典散射理论分析了单重态基态X¹Σ⁺和三重态基态a³Σ⁺的最大振动量子数. 研究了包括跃迁偶极矩、夫兰克-康登因子和辐射寿命在内的跃迁特性. 研究结果表明,这种计算方法可以为超冷碱双原子分子实验提供较为可靠的参数估计.