检索结果-南通市图书馆

A study on synthesis and oxidation mechanism of mono-alkyl phosphate

在线全文

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2009年第3期21卷 172-175,188页

作者： Sheng Wang1,Shu-yun Yan2.Qing-guo Ye2.. Chinese Research Academy of Environmental science,Beijing 100012.2.qingdao University of science and technology,qingdao 2.6042.China. Chinese Research Academy of Environmental science Beijing 100012 China qingdao University of science and {2. Qingdao 266042 China

Oxidation of white phosphorus by peroxides to produce mono-alkyl phosphate in the alcoholic solution has been studied under non-and catalytic conditions. In this paper,the mechanism of the oxidation process was analyzed. The content of mono-alkyl phosphate in the product is affected by different types of alcoholic solution and peroxide solvent. The result shows the availability of the following order for the activity of the peroxide solvent and alcoholic solutions-tert-butyl hydroperoxide>(di) benzoyl peroxide>hydroperoxide; methanol>n-butyl alcohol>phenol. Under optimized reaction conditions:n(white phosphorus)︰n(tert-butyl hydroperoxide)︰n(methanol)=1︰10︰12.reaction temperature 80 ℃,reaction time 2.5 h,products of 80.0% mono-alkyl phosphonates can be provided when white phosphorus undergoes oxidation by tert-butyl hydroperoxide in the methanol solutions. When Cu(Ⅰ),and Cu(Ⅱ) complexes are used as catalysts,it is possible to significantly enhance the oxidation of white phosphorus with the increase in the reaction rate. The order for activity of catalysts is Cu(acac)2.Cu (CH3COO)2.Cu (C3H7COO)2.CuI>CuCl2. Noticeably,with Cu(acac)2.as catalyst,the selectivity for mono-alkyl phosphonates can reach 95% under adequate reaction conditions.

关键词： white phosphorus pentoxide mono-alkyl phosphate copper

The extension of the first main theorem for π-blocks

在线全文

学校读者我要写书评

暂无评论

science China Mathematics 2006年第5期49卷 620-625页

作者： HAI Jinke Department of Mathematics, qingdao University, qingdao 2.6071, China College of mathematics ,{2. University, Jinan 2.0100, China Department of Mathematics Qingdao University Qingdao 266071 China College of mathematics Shandong University Jian 250100 China

Let π be a set of primes and G a π-separable group. Isaacs defines the Bπ characters, which can be viewed as the "π-modular" characters in G, such that the Bp′ characters form a set of canonical lifts for the p-modular characters. By using Isaacs' work, Slattery has developed some Brauer's ideals of p-blocks to the π-blocks of a finite π-separable group, generalizing Brauer's three main theorems to the π-blocks. In this paper, depending on Isaacs' and Slattery's work, we will extend the first main theorem for π-blocks.

关键词： π-block, π-separable group, π-regular classes, defect group.

Boundary conditions for the bending of a piezoelectric beam

在线全文

学校读者我要写书评

暂无评论

science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2.& ZHAO BaoSheng3 1 College of science, China Agricultural University, Beijing 100083, China 2.College of Engineering, Ocean University of China, qingdao 2.6071, China 3 School of Mechanical Engineering, University of science and technology Liaoning, Anshan 114044, China 1. College of science China Agricultural University Beijing 100083 China 2. College of Engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical Engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

Prominent feature selection of microarray data

在线全文

学校读者我要写书评

暂无评论

Progress in Natural science:Materials International 2009年第10期19卷 1365-1371页

作者： Yihui Liu School of Computer science and Information technology,{2. Institute of Light Industry,Jinan 2.0353,China [a]School of Computer science and Information technology Shandong Institute of Light Industry Jinan 250353 China

For wavelet transform,a set of orthogonal wavelet basis aims to detect the localized changing features contained in microarray *** this research,we investigate the performance of the selected wavelet features based on wavelet detail coefficients at the second level and the third *** genetic algorithm is performed to optimize wavelet detail coefficients to select the best discriminant *** are carried out on four microarray datasets to evaluate the performance of *** results prove that wavelet features optimized from detail coefficients efficiently characterize the differences between normal tissues and cancer tissues.

关键词： Microarray data Wavelet detail coefficients Feature extraction Feature selection

Scattering of SH waves induced by a symmetrical V-shaped canyon: a unified analytical solution

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2012年第4期11卷 445-460页

作者： Zhang Ning Gao Yufeng Li Dayong Wu Yongxin Zhang Fei Geotechnical Research Institute Hohai University Key Laboratory of Geomechanics and Embankment Engineering(Hohai University) Ministry of Education College of Civil Engineering&Architecture Shandong University of Science and Technology

This paper reports a series solution of wave functions for two-dimensional scattering and diffraction of plane SH waves induced by a symmetrical V-shaped canyon with different shape ratios. A half-space with a symmetrical V-shaped canyon is divided into two sub-regions by using a circular-arc auxiliary boundary. The two sub-regions are represented by global and local cylindrical coordinate systems, respectively. In each coordinate system, the wave field satisfying the Helmholtz equation is represented by the separation of variables method, in terms of the series of both Bessel functions and Hankel functions with unknown complex coefficients. Then, the two wave fields are described in the local coordinate system using the Graf addition theorem. Finally, the unknown coefficients are sought by satisfying the continuity conditions of the auxiliary boundary. To consider the phase characteristics of the wave scattering, a parametric analysis is carried out in the time domain by assuming an incident signal of the Ricker type. Surface and subsurface transient responses demonstrate the characteristics and mechanisms of wave propagating and scattering.

关键词： SH-wave scattering V-shaped canyon topographic effect wave propagation earthquake ground motion wave function expansion method

Optimization of control parameters of CdZnTe ACRT-Bridgman single crystal growth

在线全文

学校读者我要写书评

暂无评论

science China(Technological sciences) 2004年第6期47卷 725-740页

作者： LIU Juncheng School of Material science and Engineering, shandong University of {2., Zibo 2.5091, China 1. School of Material science and Engineering Shandong University of Technology 255091 Zibo China

The CdZnTe vertical Bridgman single crystal process with accelerated crucible rotation technique (ACRT) has been simulated. Effects have been investigated of the ACRT wave parameters on the solid-liquid interface concavity and the solute segregation of the crystal. The results show that ACRT can result in the increase of both the solid-liquid interface concavity and the temperature gradient of the melt in the front of the solid-liquid interface, of which the magnitude varies from small to many times when the ACRT wave parameters change. Of the ACRT wave parameters, the increase of the crucible maximum rotation rate can hardly improve the radial solute segregation of the crystal, but the variation of the crucible acceleration time, the keep time at the maximum rotation rate, and the crucible deceleration time can affect the solute segregation of the single crystal extraordinarily. With suitable wave parameters, ACRT greatly decreases the radial solute segregation of the crystal, and even makes it disappear completely. However, it increases both the axial solute segregation and the radial one notably with bad wave parameters. An excellent single crystal could be gotten, of which a majority part is with no segregation, with ACRT-Bridgman method by adjusting both the ACRT wave parameters and the crystal growth control parameters, such as the initial temperature of the melt, the temperature gradient, and the crucible withdrawal rate, etc.

关键词： crystal growth solute segregation numerical simulation CdZnTe ACRT

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

在线全文

学校读者我要写书评

暂无评论

science China Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2. CUI Yuezhi3, HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, shandong University, Jinan 2.0100, China 2. School of Information science and Engineering, shandong University, Jinan 2.0100, China 3. Department of Chemical Engineering, Light Industry College of shandong, Jinan 2.0100, China 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of science and technology, Wuhan 430074, China 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of Information science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2.4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2.4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2.methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2.. NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2.order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2.molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P2. space group. Its powder crystals exhibit a 2.order harmonic intensity 46.2.times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2.order nonlinear optical (NLO) efficiency on the micro 2.order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Mixed boundary conditions for piezoelectric plates

在线全文

学校读者我要写书评

暂无评论

science China(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2.&ZHAO BaoSheng 3 1College of science,China Agricultural University,Beijing 100083,China 2.ollege of Engineering,Ocean University of China,qingdao 2.6071,China 3 School of Mechanical Engineering,University of science and technology of Liaoning,Anshan 114044,China College of science China Agricultural University Beijing 100083 China College of Engineering Ocean University of China Qingdao 266071 China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan 114044 China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Online multiple instance regression

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2013年第9期22卷 656-661页

作者：王志岗赵增顺张长水 Department of Automation Tsinghua UniversityState Key Laboratory of Intelligent Technologie and SystemsTsinghua National Laboratory for Information Science and Technology College of Information and Electrical Engineering Shandong University of Science and Technology School of Control science and Engineering Shandong University

The multiple instance regression problem has become a hot research topic recently. There are several approaches to the multiple instance regression problem, such as Salience, Citation KNN, and MI-ClusterRegress. All of these solutions work in batch mode during the training step. However, in practice, examples usually arrive in sequence. Therefore, the training step cannot be accomplished once. In this paper, an online multiple instance regression method ＂OnlineMIR＂ is proposed. OnlineMIR can not only predict the label of a new bag, but also update the current regression model with the latest arrived bag. The experimental results show that OnlineMIR achieves good performances on both synthetic and real data sets.

关键词： mutiple instance regression online learning