非晶碳结构建模和电子结构的第一性原理研究

基于密度泛函理论，采用了一种更为精确的交换相关泛函OLYP(OPTX+LYP)，对密度范围从2.0到3.2 g/cm³的非晶碳进行结构建模. 模拟得到的5个碳网络结构无论从径向分布函数还是sp³含量都与实验符合得很好. 对非晶碳电子结构的研究表明费米能级附近的电子态密度主要是sp²碳原子的贡献. 随着密度的增加，sp³碳原子增加，费米能级附近的态密度越来越小. 小环结构增加了费米能级附近的电子态密度，缺陷态在费米能级形     

一维双相介质孔隙率的小波多尺度反演

基于多尺度的思想,将小波多分辨分析和多尺度方法结合，构造了小波多尺度反演方法，并应用于一维双相介质孔隙率的反演.利用小波变换，将原始反问题分解为不同尺度上的一系列子反问题，并按照尺度从粗到细的顺序依次求解.在每一个尺度上，都采用稳定、收敛快的正则化高斯牛顿法求解，次一级尺度上求出的“全局最优解”作为上一级的初始解，依次类推，直到求出原始问题的真正的全局最优解.将小波多尺度方法归结为三种不同算子(分解算子、求解算子、插入算子)的交替应用，给出了小波多尺度反演算法的基本流程图，并推导出当采用Daubechie     

HL-2A装置中的带状流三维特性研究和探针设计

HL-2A装置边缘等离子体测地声模带状流的三维特征采用外中平面上三组三台阶探针阵列组成具有环向、极向和径向分辨的独特结构的探针系统进行了研究.其中两组具有极向距离为65mm的三台阶5探针阵列组成极向带状流10探针组，另一组电动式带状流6探针阵列与带状流10探针组之间的环向距离为800mm. 此外，采用快速往复气动6探针组研究了磁分界面附近的温度、密度、雷诺协强及其径向分布.在HL-2A装置上同时观测到测地声模带状流(频率f=7kHz)的极向和环向对称性(m≈0，n     

Asymptotic solution for a class of sea-air oscillator model for El Nin^～o-southern oscillation

The El Nifio-Southern Oscillation （ENSO） is an interannual phenomenon involved in the tropical Pacific Oceanatmosphere interactions. In this paper, an asymptotic method of solving the nonlinear equation for the ENSO model is used. And based on a class of oscillator of ENSO model, the approximate solution of a corresponding problem is studied by employing the perturbation method. Firstly, an ENSO model of nonlinear time delay equation of equatorial Pacific is introduced, Secondly, by using the perturbed method, the zeroth and first order asymptotic perturbed solutions are constructed. Finally, from the comparison of the values for a figure, it is seen that the first asymptotic perturbed solution using the perturbation method has a good accuracy. And it is proved from the results that the perturbation method can be used as an analytic operation for the sea surface temperature anomaly in the equatorial Pacific of the atmosphere-ocean oscillation for the ENSO model.     

副热带圈和赤道太平洋年代际变更的海-气振子模型解的同伦映射方法

研究了一类海-气振子时滞方程.目的是构建一个非线性海-气振子模型的近似求解方法，利用同伦映射理论讨论了对应的问题的近似解.这是一个近似的解析方法，它能够进一步分析海-气振子模型海表温度异常的其他性态.     

Chemical Constituents from Acanthopanax senticosus and Their Cytotoxic Activities

Chemistry of Natural Compounds - A new lignan, named 1,6-bis-(3-methoxy-4-hydroxyphenyl)hexane-1,6-dione (1), together with seven known compounds (2–8) were isolated from the EtOAc-soluble...     

A New Cadmium(Ⅱ) Dimer Constructed by 1,10-Phenanthroline Derivative and Chlorine Anions: Syntheses,Crystal Structure and Photoluminescence

In this work, a new Cd(II) dimeric compound, [Cd(Cl)2(L)(H2O)]2(1, L = 2-(4-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), has been achieved under hydrothermal conditions. The structure of compound 1 was determined by single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a = 8.944(2), b = 18.781(5), c = 10.904(3), β = 91.392(4)°, V = 1831.2(8) 3, Z = 2, C38H26Cd2F2Cl4Cl4N8O2, Mr = 1031.27, Dc = 1.870 g/cm3, F(000) = 1016, μ(Mo Ka) = 1.513 mm-1, R = 0.0532 and w R = 0.1407. Each Cd(II) atom is in an octahedral coordination sphere, completed by two nitrogen atoms from one L ligand, two chlorine anions, and one water oxygen atom. Two chlorine anions bridge two Cd(II) atoms to give a dimer [Cd(Cl)2(L)(H2O)]2. Adjacent dimers are stacked by one type of π-π interactions among L ligands to generate a 1D supramolecular chain. Further, the 1D supramolecular chains are stacked by another type of π-π interactions among L ligands to give a 2D supramolecular layer. Finally, the luminescent property of 1 has been studied in solid state at room temperature.     

新型Zn2+基金属有机框架结构的温度依赖的导电、发光性能及理论计算

Anovel four-fold interpenetrating metal-organic framework (MOF) (1) was obtained following reaction between Zn²⁺ and benzene-1, 3, 5-tribenzoate (H₃BTB). Single crystal analysis demonstrated that the framework featured a three-dimensional (10, 3) net anionic framework with dimethyl formamide (DMF) and H₂NMe₂⁺ encapsulated in channels along the b axis. Alternating current impedance measurements revealed an unusual temperature-dependent conductance. As the temperature was increased from 20℃ the conductance value increased from 0.36×10^-6 S·cm^-1 to a maximum value of 2.24×10^-5 S·cm^-1 at 160℃, and then began to decrease. A combination of molecular dynamics (MD) simulations and dielectric property measurements demonstrated that this conductance behavior could be attributed to the synergic effect of the enhanced mobility of the H₂NMe₂⁺ cation and removal of DMF as the temperature was increased. Furthermore, the transporting energy barrier was determined to be 0.20 eV, which confirmed that the conductance was caused by proton conductivity. This work indicated that the confinement of H₂NMe₂⁺ within the pores of MOFs is a promising method to induce electrical conductivity. Interestingly, the emission peak of 1 was blue-shifted when compared with that of H₃BTB. Density functional theory (DFT) calculations revealed that this phenomenon was caused by the disruption of delocalized π-bonds within the BTB^3- ligand in 1.     

Highly efficient and site-selective [3 + 2] cycloaddition of carbene-derived ambident dipoles with ketenes for a straightforward synthesis of spiro-pyrrolidones

The [3 + 2] cycloaddition reaction of 2-arylthiocarbamoyl benzimidazolium, -imidazolinium, and -triazolium inner salts (the ambident C-C-N and C-C-S 1,3-dipoles derived from carbenes) with ketenes proceeded efficiently in a highly site-selective manner to produce the C-C-N cycloaddition products benzimidazoline-, imidazolidine-, or triazoline spiro-pyrrolidones in 58-93% yields. Theoretical calculation suggests a stepwise mechanism for the reaction and indicates that the C-C-N cycloaddition of the dipoles with ketenes is both a dynamically and thermodynamically favored reaction pathway. Their easy availability, high reactivity, and reaction selectivity render the benzimidazolium, -imidazolinium, and -triazolium inner salts powerful and versatile 1,3-dipoles in the construction of novel spiro heterocyclic systems, which are not easily accessible by other methods.     

The sea--air oscillator model of decadal variations in subtropical cells and equatorial Pacific SST

In this paper a time delay equation for sea--air oscillator model is studied. The aim is to create an approximate solving method of nonlinear equation for sea--air oscillator model. Employing the method of variational iteration, it obtains the approximate solution of corresponding equation. This method is an approximate analytic method, which can be often used for analysing other behaviour of the sea surface temperature anomaly of the atmosphere--ocean oscillator model.