Formation mechanism of ethanol-water excimer

The fluorescent spectrum and the excitation spectrum were used to present the cluster molecular structure feature in ethanol-water solutions.Through analyzing the fluorescent characteristics of an excimer,it is proposed that the excimers are formed between the ethanol-water cluster molecules in the excited state and in the ground state.The fluorescent lifetime and the fluorescent intensity decay process give information about the photo-physical and photo-chemical processes of the formation and the dissociation of an excimer.The theoretical calculation and physical analysis coincide with the experimental results.The preliminary conclusion about the structure feature of ethanol-water cluster molecule is that it has a planar one like a sandwich.     

Multipartite Entanglement in Heisenberg Model

The effects of anisotropy and magnetic field on multipartite entanglement of ground state in Heisenberg XY model are investigated. The multipartite entanglement increases as a function of the inverse strength of the external field when the degree of anisotropy is finite. There are two peaks when the degree of anisotropy is γ=±1. When the degree of anisotropy increases further, the multipartite entanglement will decrease and tend to a constant. The threshold of the inverse strength of the external field for generating multipartite entanglement generally decreases with the increasing of qubits.     

ON THE RADIAL GROUND STATE OF P-LAPLACIAN EQUATION WITH GRADIENT TERM PERTURBATION

1IntroductionInthispaper,weconsidertheexistence,uniqueuessandnonexistenceoftheradialgroundstatetothefollowingp-Laplacianequation:whereApu=div(IDttl)Du),n>p22,qissubcriticalexponents,i.e.,qo.Bydefinition,afunctionu(x)issaidtobetheradialgroundstateto(1.1),ifu(x)=u(r)satisfies:1)u(r),Iu'Ip-'U'eC'([o, oo));2)u(r)isthesolutionofthefollowingCauchyproblem:3)u(r)satisfiesIn0urf0rmerpaper[1],westlldiedtheexistenceanduniqueness0fradialgroundstatetoproblem(1-1)inthecasewhereq…     

Studies of the naturally occurring biomethylation of selenium and the determination of the products

A systematic study of the biomethylation of selenium and the determination of the methylated species indicates preliminarily that selenium is susceptible to natural biomethylation under certain environmental conditions. Detectable levels of methylated selenium species, including dimethyl selenide [(CH₃)₂Se], dimethyl diselenide [(CH₃)₂Se₂] and dimethylselenone [(CH₃)₂SeO₂] have been detected by gas chromatography – graphite furnace atomic absorption spectrophotometry (GC – GF AA) from a variety of environmental samples. Findings of naturally methylated selenium species from both soil samples and related air samples suggest that there may exist a localized cycle of selenium between ground soil and the ambient air. Factors that influence the sensitivity and accuracy for the determination of alkyl selenide compounds by GC – GF AA have also been investigated. Flashlike injection mode and addition of about 10% of hydrogen gas to the argon carrier gas provide for highly sensitive detection. Reproducible determination can be obtained with a precision of about 6% and the detection limits are 0.3 ng Se m^?3.     

Semistable extremal ground states for nonlinear evolution equations in unbounded domains

In this paper we show that dissipative reaction-diffusion equations in unbounded domains posses extremal semistable ground states equilibria, which bound asymptotically the global dynamics. Uniqueness of such positive ground state and their approximation by extremal equilibria in bounded domains is also studied. The results are then applied to the important case of logistic equations.     

Effects of an anisotropic parabolic potential and Coulomb’s impurity potential on the energy characteristics of asymmetrical semi-exponential CsI quantum wells

Because of its unique optoelectronic properties,people have studied the characteristics of polarons in various quantum well(QW)models.Among them,the asymmetrical semiexponential QW(ASEQW)is a new model for studying the structure of QWs in recent years.It is of great significance to study the influences of the impurity and anisotropic parabolic confinement potential(APCP)on the crystal’s properties,because some of the impurities,usually regarded as Coulomb’s impurity potential(CIP),will exist in the crystal more or less,and the APCP has flexible adjustment parameters.However,the energy characteristics of the ASEQW under the combined actions of impurities and APCP have not been studied,which is the motivation of this paper.Using the linear combination operation and Lee-Low-Pines unitary transformation methods,we investigate the vibrational frequency and the ground state energy of the strong coupling polaron in an ASEQW with the influences of the CIP at the origin of coordinates and APCP,and make a comparison between our results and previous literature’s.Our numerical results about the energy properties in the ASEQW influenced by the CIP and APCP may have important significances for experimental design and device preparation.     

Steady ground-water flow through layered media

This paper deals with the flow through a layered medium that has alternate sand and clay strata. The solutions of plane, axisymmetric and spatial cases are given. Research results in this paper can be applied to seepage calculations and hydraulic engineering designs in flood areas and reclaimed marsh land.List of Symbols A _n Upward leakage factor of the nth sand stratum - A _n Downward leakage factor of the nth sand stratum - [B] Matrix of eigenvector - B _nm Element of [B] corresponding to the nth sand stratum and the mth eigenvalue - C _m , C _N+m Arbitrary constants belonging to the terms contained the mth eigenvalue - C_mj Arbitrary constant belonging to the term contained the mth eigenvalue due to a line source in the jth sand stratum - [D] Inverse matrix of [B] - d _f0 ^sup+ Additional length of the seepage path for ditches in symmetric flow - F, ^F _m Area and dimensionless area corresponding to the mth eigenvalue ( ^F _m = _fm ^sup2 F) - f ₀ Coefficient of additional resistance of partially penetrating well - H Total water head; upstream water head - h, h _n Water head and water head of the nth sand stratum - h _nj Water head of the nth sand stratum due to a line source in the jth sand stratum - h ₀ Surface water head - h/H × 100% Potential - i, j Number - k, k Permeability coefficient of the sand stratum and clay stratum, respectively - k _n , k _n Permeability coefficient of the nth sand stratum and the nth clay stratum, respectively - L Length - m Number - N Total number of sand or clay strata - n Number - Q _j Discharge of a line source distributed along a vertical line in the jth sand stratum - Q _ji The partial discharge of the ith well (or line source), which flows through the screen pipe penetrating the jth sand stratum - qj Discharge of a face source distributed on an area - unit breadth multiplied by the thickness of the jth sand stratum. The abbreviation is: unit discharge of a face source in the jth sand stratum - qji Unit discharge of a face source on the ith surface element in the jth sand stratum - R Constant radius - S Distance; length of a curve - ^S _m Dimensionless length of a curve corresponding to the mth eigenvalue ( ^S _m = _m S) - s Number - T _n , T _n Thickness of the nth sand stratum and the nth clay stratum, respectively - t Number; thickness - x, y, z Cartesian coordinates - y Polar coordinate; radius; distance - ^y _m Dimensionless distance corresponding to the mth eigenvalue ( ^y _m = _m y) - y ₀ Radius of well - y ₀ Radius of equivalent completely penetrating well - Infinitesimal half breadth - Infinitesimal area - Angle - Eigenvalue     

Theoretical prediction on HBeN− and HNBe− anions using multiconfiguration second‐order perturbation theory

The HBeN^? and HNBe^? anions have been investigated for the first time using the CASSCF, CASPT2, and DFT/B3LYP methods with the contracted atomic natural orbital (ANO) and cc‐pVTZ basis sets. The geometries of all stationary points along the potential energy surfaces were optimized at the CASSCF/ANO and B3LYP/cc‐pVTZ levels. The ground and the first excited states of HBeN^? are predicted to be X²Π and A²Σ⁺ states, respectively. It was predicted that the ground state of HNBe^? is X²Σ⁺ state. The A²Π state of HNBe^? has unique imaginary frequency. A bend local minimum M1 was found along the 1²A″ potential energy surface and the A²Π state of HNBe^? should be the transition state of the isomerization reactions for M1 ? M1. The CASPT2/ANO potential energy curves of isomerization reactions were calculated as a function of HBeN bond angle. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010     

非线性Schrdinger方程基态解的一致集中

本文讨论一类非线性Schrdinger方程-ε~2△v+V(z)v=K(x)v~p,x∈R~N,v∈W~(1,2)(R~N),v(x)>0,势函数V(x)有正下界和在无穷远处为零两种情形.通过强最大值原理我们证明方程的基态解关于充分小的ε>0一致集中.     

大尺度粗糙地面的电磁散射特性

 综合考虑空间区域分割、消息传递、负载平衡及同步和边界处理等因素,给出了计算随机粗糙地面电磁散射的并行时域有限差分算法流程,并在大型高性能并行机上应用。理论分析和仿真结果表明：该算法可以快速准确地计算大尺度随机粗糙地面的电磁散射特性;通过与经典解析方法的比较,验证了该算法的正确性和实用性,在大尺度情况下拟合结果更好,更能体现地面的统计特性。