CALCULATION OF THIN PLATES BENDING EEFORMATION AND CRITICAL PRESSURE BY THE TCHEBYCHEV''S POLYNOMIALS

In this paper trial functions of the second Tchebychev's polynomials is used with Cantorovich variational method in energy functional of thin plate. Bending deformaion of rectangle plate under even loads or concentrate force with several bearing and critical pressure in buckling is resolved. Though the first similar is used but calculations indicate that this method is simple and exact in engineering.     

Boundaty Element Method for Analysis of Thick Plates on Two- Parameter Elastic Foundations

This paper discusses the Reissner's plates on elastic foundation.The elastic foundation is considered as two- paramerer and its effect to thick plates are taken into account by a set of govering differential equations. According to the foundamental solutions for bending problem on two- parameter foundation derived, three boundary integral equations denoted by generalized displacement functions are established. This method is suitable to solve the bending problem of thin or thick plates on two- parameter foundation with arbitary boundary condition, arbitary shape and arbitary load conditions     

THE THEORETICAL ANALYSIS OF RADIAL DISPLACEMENT AND COMPATIBLE CONDITIONS OF BOTTOM PLATE OF PISTON FRAME IN LARGE CONTAINER

Taking aecount of shear action between the piston truss the bottom plate, this paper assumes the bottom plate to be a part-ring and supposes that the shear distribution follows the power series law, making the problem to be a problem of mixed boundary condition of part plate. In the paper, the solution of this elastic plane problem is derived. The general expressions of radial displacement of bottom plate are given. The compatible conditions both at the nodes of the lower chord of the truss and at the central cylindrical shell are analyzed.     

Static Behavior of Rigid Connections of H-beams with Corrugated Webs

Steel H-beams with corrugated webs can provide high shear-buckling resistance with very thin webs, which results in saving of steel. Common beam-to-column rigid connections are not suitable for H-beams with corrugated webs, so 2 types of rigid connections are proposed .In this paper,2 static tests of beam-to-column rigid connections of H-beams with corrugated webs were conducted. And the test results were compared with the results from finite element analysis and the results calculated from the practical design formulas to verify the validity of the results from ABAQUS FEA and reliability from the practical design formulas. Parametric studies were carried out to investigate the bearing capacity of the pinned connection with variations in the thickness of the endplate, the connecting plate and the corrugation at the breaking point.     

Research on Shoelast CAD/CAM Technology

Some new developments of boundary contour method have been presented in this paper. The developments include the boundary contour method based on equivalent boundary integral equations, the traction boundary contour method as well as the application of the boundary contour method to crack problems and elastic thin plate bending problems.     

CALCULATION OF CYLINDRICAL BENDING PROBLEM FOR RECTANGULAR PLATES BY ELASTIC AND TENSILE SUPPORTS

In this paper, the solution of cylindrical bending problem for rectangular plates supported by elastic and tensile supports on particular deformation condition are derived from practical engineering problem. By examples, some considerable matters of analysing prismatic structures are suggested. The solutions are also studied when the tensions are to be determined. the results are simple and easy to be used.     

ANALYTICAL SOLUTION OF RING SHELL LINING WITH ANNULARLY VERTICAL WALLS MADE CONTACT WITH SURROUNDING ROCK

In this paper,the ring shell lining with annularly verticalwalls made contact with the surrounding rock is considered as a combinationstructure formed of ring shell,inner and outer annular barrels on elastic fo-undation.The complex equation and its solutions of ring shell under deadload of lining and vertical and horizontal surrounding rock pressures are de-rived by the method of complex function.The governing equation and itssolution of the barrels on elastic foundation are also derived by theory ofcylindrical shell.And then,the ring shell lining is assembled by the subst-ructures by means of compatibility conditions of internal forces and defor-mations between them.In the paper,all formulas for the practical computa-tion in engineering are derived,the numerical examples are given and theeffects of the parameters of the lining on the work behaviours of lining alsoare discussed preliminarily     

Calculating Critical Loads of Thin Plates With Method of Weighted Residuals

In elastic mechanics, it is common practice to calculate critical loads in buckle of thin plates by means of double triangle series. The calculation process is more complex, this method has not facility in engineering application. In many cases critical loads of thin plates can not obtain precise analytic solutions. It is very important to solve approximate resolutions of critical loads of plates in engineering. The method of weighted residuals is an available measure to solve proximal resolutions of differential equations and has extensive application in egineering. In order to simplify calculation process and obtain profitble result, by means of method of weighted residuals and Cantorovich variational principle, taking the second Tchebychev's polynomials as trial functions, it was calculated, critical loads of rectangle thin plates in different supporting conditions. Calculation results indicate that this calculation method is simple and has some precision, it is applied conveniently in engineering.     

Galerkin Approximate Solutions of Displacement Including the Effect of Dead Loads for Two Kinds of Rectangular Plates

Based on the strain energy considering the effect of dead loads, the general form static equilibrium differential equations were formulated by means of the potential energy principle. The approximate solutions of live load or later load displacement including the effect of dead loads for the clamped rectangular plate and the simply supported rectangular plate were generated by the Galerkin method. These formulas are simple and clear, and their physical concepts are explicit. The correctness of these formulas was verified by the finite element method. The dead loads and other factors that influence the effect of dead loads are shown by these formulas. The effect of dead loads on the two different boundary condition rectangular plate were analyzed by these approximate solutions. The effect of dead loads improves the bending stiffness of plate and minimizes the displacement of live loads or later loads. The key physical factors governing the effects of dead loads on plates are the dead load, the ration of span to thickness and boundary condition etc. This effect of dead loads is not negligible, especial in thinner plates or plates with smaller stiffness, more attention should be paid to the effect of dead load in the calculation and analysis for plates.     

Axisymmetric Loaded Elastic Circular Plate on Multi Layered Soil

An analytical solution of the elastic circular plate on multi layered soil can be obtained by using the transfer matrix solutions for displacements and stresses of multi layered soil. This solution is based on the continuity of vertical displacements and the smooth contact conditions between a multi layered soil surface and the elastic circular plate. Numerical calculation and analysis are carried out by the computer program compiled for this purpose. The numerical results show that the rigidity of the elastic circular plate greatly influences the displacement of the circular plate and the normal stresses under the center of the circular plate.     

猪源肠球菌两种致病基因和表型的检测

摘要：目的：调查53株猪源肠球菌2种致病基因和2种表型的分布。方法：应用聚合酶链反应检测53株肠球菌的2种致病基因,用50mL/L兔血平板和30g/L明胶平板检测β溶血和明胶溶解表型。结果：粪肠球菌、屎肠球菌和鸟肠球菌2种致病基因的检出率分别为cylA 94.4%、96.9%、100%; gelE 100%、87.8%、50%;β溶血检出率分别为72.2%、42.4%、0;明胶溶解检出率分别为100%、0、0。结论：细胞溶解素激活基因(cylA)明胶酶基因(gelE)为猪源肠球菌的主要致病基因;粪肠球菌2种致病基因和2种表型的检出率高于屎肠球菌;来源于新鲜猪肉中的粪肠球菌存在较强的毒力,提示注意食品卫生安全;在新鲜猪肉中检测到2株鸟肠球菌,基因型和表型检测说明其存在较弱毒力。     

Out-of-Plane Mechanical Properties of Masonry Wall with Homogenization

Based on the three-dimensional homogenization theory, the Characteristic 3D elementary pattern in the masonry was established. The homogenized masonry wall was considered as a vertical plate with four supports. The plate theory was used to research the out-of-plane mechanical properties of masonry panels. Homogenization models with theory of thin plates and theory of medium and heavy plates were given and the calculation formula of deflection of homogenization masonry wall were deduced as well. The mid span deflections of 120 mm, 180 mm, 240 mm and 370 mm masonry walls with both fixed and variable ratio of height to width were analyzed. The applicability of two kinds of plate theories on homogenization masonry walls of different sizes was obtained. This methodology was practical and the masonry theory was improved.     

油菜小孢子培养技术体系研究

小孢子培养在油菜的基础研究和应用研究中均具有十分重要的意义。自1982年Lichter首次在甘蓝型油菜中进行小孢子培养获得成功以来,国内外在油菜小孢子培养技术方面已取得大量研究成果,包括油菜小孢子胚状体发生的影响因素,小孢子植株的再生、成苗、大田移栽、染色体加倍等,近年来又对一些关键技术环节加以了改进,笔者在对这些研究成果进行总结的基础上针对中国国情建立了大田条件下油菜高效小孢子培养技术体系。用该体系对甘蓝型油菜和新疆野生油菜的体细胞杂种后代进行小孢子培养的出胚率达到300枚/皿以上,采用小孢子苗直接移栽大田技术,成活率达到89.0%。此外还成功构建了含127个DH系的黄籽油菜DH群体及含115个DH系的粒重分离群体。     

甜瓜种子传带真菌初步研究

采用洗涤检验法和PDA培养基法对来自北京、河北、黑龙江、辽宁、吉林、陕西、甘肃、河南、安徽和上海等地的32个甜瓜品种的种子传带真菌情况进行检测。结果表明,干种子、种子洗涤悬浮液、水洗后种子和1%NaClO处理后的甜瓜种仁均检测到青霉菌、曲霉菌、镰刀菌和链格孢菌;经1%NaClO处理过后的甜瓜种子、种皮和种仁的带菌率明显低于干种子的带菌率,且经1%NaClO处理过后的甜瓜种子和种皮未检测到曲霉菌。     

NONLINEAR ANALYSIS OF LAMINATED ANGLE-PLY PLATE USING A HIGHER-ORDER SHEAR DEFORMATION THEORY

A higher-order shear deformation theory is used to analyse nonlinear bending of symmetrically laminated angle-ply rectangular plates. The nonlinear governing differential equations are solved here by using perturbation method. Numerical rerults are presented graphically for vairous parameters of laminated plate. The present solutions are compared with those obtained using the classical plate theory. A lot of significient conclusions are obtained.     

Deformation equations of thin-walled open-profile members considering distortion and its application

In order to simplify the analysis of thin-walled open-profile bars, a method is presented in which the analysis is split into two parts, dominated by in-plane and out-plane loading effects respectively. This article focuses on the out-plane loading effects. Based on bending theory of thin plate with small deflection, each slab or strip is analyzed separately and the results are integrated into vectors, in which, the deformation shapes and equilibrium conditions are simplified appropriately, thus leading to the slabs' out-plane bending resistance system of thin-walled bars, which reflects the properties of the bar's distortion and torsion. By composing the slabs in-plane tension-bending resistance system and the slabs' out-plane bending resistance system, deformation equations of thin-walled open-profile bars considering distortion are deduced. In order to set up the finite bar element method, stiffness equation and equivalent nodal forces of internode loadings are deduced. Comparative analysis with finite shell element method indicates the high efficiency and accuracy of this method.     

The Element-free Method for Elastic Foundation Plates(EFM)

The application of the element-free method in the bending problems of plates has not been found since it was proposed.In this paper,the element-free method is applied to compute the deflection and the moment of the elastic foundation plate with free boundary,and the corresponding formulas as well as the computer program are developed.Numerical examples show that the accuracy of the method used in the foundation plate problem is satisfactory.Therefore,it is reasonable and feasible for using the element-free method in the plate bending problems.     

转梭梭HaPrxQ基因拟南芥植株的获得与检测

HaPrxQ是参与活性氧清除的重要基因。根据已发表的过氧还蛋白基因序列,设计特异引物,扩增到完整的HaPrxQ基因;构建植物表达载体pCAMBIA2300-HaPrxQ,通过农杆菌介导转化拟南芥,获得转化植株种子。对收获的T0代种子进行卡那霉素抗性筛选,并通过PCR对抗性苗进行检测。结果表明,构建的载体成功转化拟南芥并获得了9份转HaPrxQ基因苗。     

油菜小孢子培养影响因素及黄籽油菜双单倍体群体的构建

针对我国油菜小孢子培养供体材料一般种植在大田,受外界环境影响较大,出胚率较低的现状,对大田环境条件下小孢子培养的主要影响因素进行了研究。同时,为了构建黄籽油菜双单倍体群体,研究了黄籽油菜的出胚情况。结果表明,不同取样时间对小孢子胚状体再生频率的影响很大;秋水仙素处理游离小孢子对胚状体的诱导有一定的负面影响,浓度越高,影响越大;黄籽油菜的出胚率较低(0.56枚/皿),同样条件下,不到黑籽油菜的1/8。不同黄籽单株间出胚率差异较大,变异幅度在0.04~1.97枚/皿。采用小孢子苗直接移栽大田技术,移栽成活率达89.0%,经染色体加倍后,最终构建了含有127个株系的黄籽油菜双单倍体群体。     

CALCULATION OF CONTACT PRESSURE UNDER FOUNDATION RESTING ON VISCO-ELASTOPLASTIC SUBGRADE

In this paper, the finite element method(FEM) is carried out for the contact pressure under circular foundation with visco-elastoplastic model and a 8 node finite element program determing parameter. In order to prove the reliability of the theoretical analysis, a circular rigid loading plate test on remolded clay is done. Otherwise, a comparison of the measuring contact pressure under box foundations of highrise buildings in Beijing and Shanghai with the calculated value by different method is made. The result shows the calculated value by the method proposed in this paper is more coincident with practical data.