I: METHODOLOGY

Since standard molecular simulations use different energy expressions for charge and gradient calculations, there are severe problems such as incompleteness in the optimization and simulation of the system with electrostatic (ES) interaction. Here, a new concept is proposed to solve this problem. The consistent charge equilibration (CQEq) equation has been derived which uses the same energy expression for both charge and gradient calculations. The ES energy is given by the atomic partial charge shielded with a nuclear charge described by a normalized S type Slater function located at each atomic site. The partial charge is determined by the variational principal for the ES energy with a constraint that the total sum of the partial charges is constant. Also the first derivative has been determined for the ES energy to the internal coordinates from the same ES energy expression. Although the CQEq is a little heavier than the original QEq for the charge calculation, the CQEq completely satisfies the variational principle for the ES energy of a set of partial charge, and satisfies the consistency requirement in the optimization of the system with ES interaction. A new code has been created and applied to test cases.     

Detection of Single Molecule on Water Surface by Confocal Fluorescence Microscopy

In the past decade,several research groups have succeeded in observing single molecule in liquid, and more recently at silica surface in the near-field mode as well as at polymer-air interface in far-field mode. Due to the significance of air-water interface in surface chemistry, we prospect that research works on single molecule detection (SMD) of the air-water surface could open a new era in surface photochemistry and photophysics.     

Laser Spectroscopy on Water Surface

The water surface has unique properties, which are different from those in the bulk and have exceptional scientific and environmental importance. Surface tension has been measured, but is not versatile for a molecular point of view. Recently laser spectroscopy has appeared as a sensitive tool to investigate water surface on a molecular basis. There are three major laser techniques to study the water surface:the photoionization, the second-harmonic and sum-frequency generation, and the laser-induced fluorescence. Recent progresses in these fields are overviewed based mainly on investigations carried out in my group.     

Design and synthesis of biologically active carbaglycosylamines: From glycosidase inhibitors to pharmacological chaperones

For over 50 years, our group has been involved in synthetic studies on biologically active cyclitols including carbasugars. Among a variety of compounds synthesized, this review focuses on carbaglycosylamine glycosidase inhibitors, highlighting the following: (1) the naturally occurring N-linked carbaoligosaccharide α-amylase inhibitor acarbose and related compounds; (2) the novel synthetic β-glycosidase inhibitors, 1′-epi-acarviosin and its 6-hydroxy analogue as well as β-valienaminylceramide and its 4′-epimer; (3) the discovery of the β-glycosidase inhibitors with chaperone activity, N-octyl-β-valienamine (NOV) and its 4-epimer (NOEV); and (4) the recent development of the potential pharmacological chaperone N-alkyl-conduramine F-4 derivatives.     

STRUCTURE OF PHOTOSYSTEM I AND PHOTOSYSTEM II OF PLANT CHLOROPLASTS*,†,§

Abstract— The action of Triton X-100 upon photosynthetic membranes which are devoid of carotenoids produces a small Photosystem I particle (HP700 particle) which is active in N ADP photoreduction and has a [Chl]/[P700] ratio of 30. The properties of the HP700 particle indicate that it is a reaction center complex which is served by an accessory complex containing the additional light-harvesting chlorophyll of Photosystem I as well as the cytochromes and plastoquinone. When Photosystem II particles obtained by the action of Triton X-100 are further washed with a solution 0.5 M in sucrose and 0.05 M in Tris buffer (pH 8.0), chlorophyll-containing material is released. After centrifugation, the supernatant contains about 1 per cent of the chlorophyll and contains three types of particles which can be separated by sucrose density gradient centrifugation. One of these particles, designated TSF-2b, has the same pigment composition as the original Photosystem II fragment, contains cytochrome 559, and shows Photosystem II activity (DCMU-sensitive diphenylcarbazide-supported photoreduction of 2,6-dichlorophenolindophenol). The other two particles (TSF-2a and TSF-2a′) have a [Chl a]/[Chl b] ratio of 8, have a low concentration of xanthophylls, and show a [Chl]/[Cyt 5591 ratio of about 20. Only the TSF-2a particle is active in the Photosystem II reaction described above. On the basis of these data, it is proposed that the Photosystem II unit consists of a reaction center complex which contains Chl a, Cyt 559, and an acceptor for the photochemical reaction. The reaction center complex would be served by an accessory complex which contains the light-harvesting pigments, Chl a. Chi b, and xanthophyils.     

Polymer-Coated Fibrous Packing Materials in Metal Capillary Gas Chromatography

Gas chromatography (GC) is one of the most versatile separation methods for volatile compounds, and a variety of polymeric materials as the stationary phases have been developed for various applications. In contrast to the successful applications and commercialization of the polymer-coated columns, the reports for the fibrous     

GaN外延层中的缺陷研究

采用阴极射线致发光法观察金属有机物汽相外延法生长的具有不同表面形貌的GaN外延层中黄色发光带的强度分布.结果表明六角金字塔形表面形貌对发光强度分布的测量有很大影响.测量和比较表面镜面加工样品的黄色发光带强度分布、原子序数衬度和X射线波谱发现,黄色发光带的强度在含有O和C等杂质缺陷附近较强.高分辨透射电子显微镜观察表明,杂质缺陷区的晶格结构不同于GaN基质,以及位错和裂缝等由应力引起的缺陷.认为此类缺陷可能是生长过程中,杂质在结晶小丘合并处的V形凹角中的沉积所产生. 关键词：     

A Taylor-Galerkin Method for Modeling Unsteady Fluid Flow Under its Own Weight

The free fluid-surface of incompressible creeping flows is analyzed using a finite element method. A pseudo-concentration (PC) function is introduced to determine the position of the free surface. The Taylor-Galerkin finite element method (TGFEM) is applied to solve the equation of the PC function. Nine-node quadratic interpolation is used for both PC and velocity. The unsteady flows of fluids moving of their own weight are analyzed using the proposed method.     

ChemInform Abstract: Resonant Two Photon Ionization Spectroscopy of the Molecules V2, VNb,and Nb2

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