Synthesis, Bioactivity, and Crystal Structure Analysis of 2-(3-Oxobenzo[d]isothiazol-2(3H)-yl)ethyl Benzoates

Fifteen novel 2-（3-oxobenzo[d]isothiazol-2（3H）-yl）ethyl benzoates were synthesi- zed by the condensation of 2-（2-hydroxyethyl）benzo[d]isothiazol-3（2H）-one with substituted benzoic acids in dichloromethane. All the compounds were characterized by elemental analysis, IR, ESI-MS and 1H NMR. The crystal structures for 2-（2-hydroxyethyl）benzo[d]isothiazol-3（2H）-one （2） and 2-（3-oxobenzo[d]isothiazol-2（3H）-yl）ethyl 2-methoxybenzoate （30） have been determined by X-ray crystal structure analysis. Compound 2 （C9H9NO2S） crystallizes in the monoclinic system, space group Pn with a = 10.552（3）, b = 7.849（2）, c = 10.765（4） A, β = 103.128（4）°, V= 868.3（5） A3, Mr = 195.24, Dc = 1.493 Mg.m-3, μ = 0.33 mm-1, F（000） = 408, Z = 4, R= 0.0314 and wR= 0.0628. Compound 30 （C17H15NO4S） crystallizes in the triclinic system, space group P1 with a = 8.028（2）, b = 9.300（2）, c = 10.430（3）A, V= 752.1（3）A3, Mr = 329.36, D,= 1.454 Mg.m-3, p = 0.24 mm-1, F（000） = 344, Z = 2, R = 0.0377 and wR = 0.0904. The preliminary biological test indicated that the title compounds show better growth inhibitory activity against the gram-positive bacteria than the gram-negative bacteria.

Crystal Structure,Photoluminescence and Theoretical Studies of Diethyl 4,5-di(thienyl)-3,6-bis(trimethylsilyl)phthalate

The crystal structure of the title compound, diethyl 4,5-di（thienyl）-3,6-bis（trime- thylsilyl）phthalate （C26H3404S2Si2, Mr = 530.83）, has been determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pccn with a = 43.008（5）, b = 10.9000（12）, c = 11.9357（14） A, V= 5595.3（11） A3, Z = 8, F（000） = 2256, Dc= 1.260 mg/m3, p = 0.305 mm-1, T = 113（2） K, S = 1.090, R = 0.0413 and wR = 0.0969 for 5952 observed reflections with 1 〉 2o（/）. The benzene ring system is planar and makes dihedral angles of 63.7（2） and 72.5（4） with the two thienyl rings A （C（23）-C（26）, S（2）） and B （C（19）-C（22）, S（1））, respectively. The UV-vis absorption and fluorescence of the title compound were discussed. The molecular structure of the title compound has been optimized using DFT method at the B3LYP/6-31G（d） level. The computational results showed that the optimized geometer parameters are consistent well with the experiment data. The vertical ionization potential, vertical electron affinity and frontier orbitals were also discussed.

Topology optimization of 3D structures with design-dependent loads

Topology optimization of continuum structures with design-dependent loads has long been a challenge. In this paper, the topology optimization of 3D structures subjected to design-dependent loads is investigated. A boundary search scheme is proposed for 3D problems, by means of which the load surface can be identified effectively and efficiently, and the difficulties arising in other approaches can be overcome. The load surfaces are made up of the boundaries of finite elements and the loads can be directly applied to corresponding element nodes, which leads to great convenience in the application of this method. Finally, the effectiveness and efficiency of the proposed method is validated by several numerical examples.

Formation of Hybrid Ring Structure of Cyanurate/Isocyanurate in the Reaction be-tween 2,4,6-Tris(4-Phenyl-Phenoxy)-1, 3,5-Triazine and Phenyl Glycidyl Ether

Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins, compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring structure through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy.

Investigation on 3Dt wake flow structures of swimming bionic fish

A bionic experimental platform was designed for the purpose of investigating time accurate three-dimensional flow field, using digital particle image velocimetry （DSPIV）. The wake behind the flapping trail of a robotic fish model was studied at high spatial resolution. The study was performed in a water channel. A robot fish model was designed and built. The model was fixed onto a rigid support frame- work using a cable-supporting method, with twelve stretched wires. The entire tail of the model can perform prescribed motions in two degrees of freedom, mainly in carangiform mode, by driving its afterbody and lunate caudal fin respectively. The DSPIV system was set up to operate in a trans- lational manner, measuring velocity field in a series of parallel slices. Phase locked measurements were repeated for a number of runs, allowing reconstruction of phase average flow field. Vortex structures with phase history of the wake were obtained. The study reveals some new and complex three-dimensional flow structures in the wake of the fish, including ＂reverse hairpin vortex＂ and ＂reverse Karman S-H vortex rings＂, allowing insight into physics of this complex flow.

Synthesis,Crystal Structure and Spectroscopic Properties of 1,2-Benzothiazine Derivatives:An Experimental and DFT Study

1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide（2） were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared（IR） spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory（DFT） at the 6-31G＋（d） basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential（IP）, Electron Affinities（EA） and coefficients of the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） of com- pounds 1 and 2 were simulated for the first time.

Numerical analysis of the failure process of soil-rock mixtures through computed tomography and PFC3D models

Soil-rock mixture （SRM） is a unique type of geomaterial characterized by a heterogeneous composition and a complicated structure. It is intractable for the continuum-based soil and rock mechanics theories to accurately characterize and predict the SRM＇s mechanical properties. This study reports a novel numerical method incorporating microfocus computed tomography and PFC3D codes to probe the deformation and failure processes of SRM. The three-dimensional （3D） PFC models that represent the SRM＇s complex structures were built. By simulating the entire failure process in PFC3D, the SRM＇s strength, elastic modulus and crack growth were obtained. The influence of rock ratios on the SRM＇s strength, deformation and failure processes, as well as its internal mesoscale mechanism, were analyzed. By comparing simulation results with experimental data, it was verified that the 3D PFC models were in good agreement with SRM＇s real structure and the SRM＇s compression process, deformation and failure patterns; its intrinsic mesomechanism can be effectively analyzed based on such 3D PFC models.

Synthesis,Characterization and Antibacterial Activity of 3-(2-(Heterocyclo-2-ylthio)-ethoxy)benzo[d]isothiazoles

Seven novel 3-（2-（heterocyclo-2-ylthio）ethoxy）benzo[d]isothiazoles（3a^3g） have been synthesized and characterized by ESI-MS and 1H and 13 C NMR spectra. The crystal structures of 3a and 3g have been determined. Compound 3a（C（11）H（11）N5O1S2） belongs to the monoclinic system and 3g（C（12）H（11）N3OS3） to the triclinic system. The title compounds show excellent in vitro antibacterial activities, with the minimum inhibitory concentrations varying from 4 to 32 ug/m L.

The Characteristics of Putaohua Reservoir and Development Strategies in Xujiaweizi Baxin Oilfield

With the using of new full 3 - D interpretative technology, the carefully interpretation of the micro - amplitude structures and faults by the reprocessed 3 -D seismic data in IES (Interactive Exploration System) interpretative system of Sun workstation is obtained. Because of the application of the well - advanced predictive technique for reservoir lithological changes, the predictive accuracy rate of drilling for 31 wells drilled in 1996 achieved 100 % and the economic and social benefits are desirable.

龙门山前中段地震剖面的构造分析

磁峰场-鸭子河构造属于青藏高原东缘的龙门山山前中段推覆构造单元,其下盘隐伏着众多的油气构造圈闭, 是前陆盆地山前油气勘探的重要目标。应用现代构造地质学的几何变形解析方法,来搭建磁峰场-鸭子河地震勘探区地表至深部的构造变形类型、构造叠加组合样式以及相应的构造模型;以正演平衡地质剖面技术为手段,验证构造模型的合理与否,同时再现龙门山中段山前的构造演化过程;在构造建模的基础上对磁峰场-鸭子河构造进行了三维构造分析,配以计算机可视化成图技术,构建出三维构造模型。

磁阻反应式有限转角电机特性分析

介绍了磁阻反应式有限转角电机的主要结构及工作原理。由于其独特的不对称结构,必须进行三维电磁场仿真分析。通过仿真,分别得到磁链、电感、转矩与电流和转子位置角的三维曲面图,建立相关数据库,并分析了电机的静态特性。根据非线性磁参数法,建立了电机的数学模型。将电机的磁化曲线数据ψ(i,θ)转变为i(θ,ψ)的形式,代入数学模型中。再采用四阶Runge-Kutta法和有限元法求解电压平衡方程和机械运动方程,得到线圈电流、转矩、转子位置角等参数的动态特性曲线。并进行了静态转矩和动态特性实验。将实验结果与仿真结果进行比较,结果证明了求解方法的正确性。