法向应力

The relationship between stress and strain of concrete in prestressed concrete bridge s is written as algebraic form within load duration and the equilibrium equations of internal force and compatibility conditions are introduced.

首先将预应力混凝土桥梁中考虑收缩、徐变影响的任意时刻混凝土应力、应变关系在持荷时段内写成代数形式，引入内力平衡方程及变形协调条件后，提出了计入截面上钢筋位置、配筋率、预应力钢筋松弛、混凝土弹性模量随时间变化等影响的徐变效应分析的全量形式自动递进法，并建立了计算式，适用于任何形式的收缩、徐变特性表达式；基于建立的全量形式公式，可方便地求解任意时刻混凝土、钢筋的应力与应变和梁体竖向变形。

A new definition of L parameter for considering the three dimensional stress distribution caused by hoop stress and torsion shear stress is made and the L solutions of these structures under various multiple loads are developed in the form of the simultaneous equations and a single exponential function equation.

另外还给出了在三维应力状态下的含缺陷结构L参量的新定义，针对多载荷作用下的周向裂纹管提出了求解L参量的联立方程法、幂指数法。

A 3-D finite element system of lumbar L4-5 was sectionally constructed with Mimics software system by lumbar CT images. The system was turned into a finite element system of degenerative lumbar by modified it's material parameter. The lumbar rotatory manipulation was decomposed by principium of manipulation. The parameter of mechanics was analyzed with the finite element system.

使用腰椎CT片，以Mimics软件系统逐层重建L4-5三维有限元模型，通过设定结构的参数完成退变腰椎间盘模型将向右侧旋转的坐位腰椎旋转于法进行分解，把各项力学参数代人模型进行计算分析即时显示于法作用时退变腰椎间盘的内在应力和位移的变化。

By using static equilibrium law, nonlinear buckle behavior of string in deep well has been researched. In comprehensive consideration of gravity, contact force of borehole wall, axial friction and tangential friction of borehole wall on the string, pressure and viscous resistance of fluid outside of and inside of a string, differential equation of buckle has been established, which amended computational model of axial load on a string.

应用静力平衡法对深井注入管柱的非线性屈曲行为进行了研究，建立了综合考虑重力、井壁支反力、井壁对管柱的轴向摩擦力和切向摩擦力及管柱内、外流体压力和粘滞阻力联合作用下的屈曲微分方程，对注入管柱的屈曲变形及弯曲附加应力等后屈曲行为进行分析，修正了管柱轴向载荷计算模型。

However, in designing the beamless slabs with equivalent frame method, the stress is an average values along the depth of section, which varies with the normal service state. Compared with the results by finite element method, the results gained by equivalent frame method cannot satisfy the requirement under the normal service state. Therefore, the tendons of beamless slabs should be designed and arranged based on the results of FEM taking account into vertical load and prestressed load.

本文通过分析，认为采用等代框架法进行无梁板设计时，其内力是基于截面平均的结果，在正常使用状态与实际受力状态有很大的不同，通过对比等代框架法和有限元计算的正常使用极限状态应力可知，按等代框架法设计的预应力布置并不能保证其正常使用极限状态的要求，据此提出了应根据无梁板在竖向荷载和预应力共同作用下弹性有限元分析结果进行预应力筋布置的建议。

Take DMSO swollen treatment and DEA-SO2-DMSO decrystallization treatment for example, the X-ray diffraction and the Tobolsky's intermittent stress relaxation of treated woods were determined during soaking in water, analyzed the effects of water on crystal degree and inter-cohesion of treated woods. According to these continuous relaxation curves measured in water with different temperatures, various thermodynamic quantities were obtained by using Eyring absolute rate theory, and reviewed the chemical reactions in wood which occur in different relaxation process. For the first time quantify these crosslinkings formed in the process of tensional relaxation by using the SMCIR intermittent stress relaxation way, and defined the cross-linking reaction types. In order to find out the contribute of drying to the fixation of deformation of chemically treated wood, stress relaxation of oven-dry untreated and treated wood was measured during the process of temperature elevation and descend, then analyzed the effect of temperature change on relaxation mechanism of treated oven-dry wood. According to continuous relaxation curves of oven-dry treated wood under various constant temperature, calculated the thermodynamics of relaxation process and discussed the mechanism of molecule change in wood, at the same time, also quantified these cross-linkings produced in wood by intermittent method and on the basis of which the model of molecular change during relaxation process of chemically treated was constructed.

以DMSO膨胀处理及DEA- SO2-DMSO非晶化塑化处理为例，测定了两种处理木材在水浸渍过程中的X射线衍射及Tobolsky间歇应力松弛，分析了水对处理木材结晶度及内部凝聚力的影响；通过未处理和两种处理木材在不同温度水中的连续应力松弛测定，应用Eyring的绝对速度反应理论计算并获得了松弛过程中的各热力学量，分析了在水中松弛过程中不同阶段木材内部发生的化学反应；并首次采用SMCIR连续·不连续双曲线应力松弛法定量了轴向拉伸应力松弛过程中木材内部产生的架桥量，明确了交联反应的类型；为了了解干燥对处理木材塑性变形固定的影响，测定了未处理和两种处理绝干木材在温度下降过程和上升过程中的应力松弛，分析了温度变化对处理绝干木材应力松弛的影响；根据多个温度水平下的连续应力松弛测定曲线，计算松弛过程的热力学量，考察了绝干木材在松弛过程中内部发生的分子变化机理，同时也用间歇法定量了木材内部新形成的架桥量，并在此基础上构筑处理木材在松弛过程中内部分子构造的变化模型。

Incurrent research, aiming at the rupture problem engendered in the shooting process of acertain 5.56mm automatic rifle, the strain and stress distributions on the cartridge caseunder the action of axial pull have been analyzed. Based on the theories of elastic-plasticmechanics and contact mechanics, a mathematic and physical model of the cartridge-caseand chamber system has been set up; and based on the platform of the general softwarepackage APDL of ANSYS for finite element analysis, a parameterized model of thecartridge-case and chamber system has also been established. The method for nonlinearFEA has been adopted to analyze the stress distribution on the entire cartridge-case andchamber system, and the method of contact element has been employed to investigate thecontact stress between the cartridge case and chamber, and then the influences of frictioncoefficient and locking space on the static and dynamic stress and strain response of thecartridge case and chamber to the action of power gas have also been discussed. On thebasis of a lot of numerical tests, a kind of element Plane13, which is concentrated incoupled computation of heat and construction, has been used finally to simulate thetransient response of the cartridge-case and chamber system to the power gas. Throughloading the temporary thermal characteristics of explosive gas in the procedure of emulate, the corresponding transient thermal stress distributed on the entire system under thecombined load of transient thermal stress and transient pressure has been obtained. Owingto these comprehensive considerations, the numerical results obtained in this paperrepresent the actual situations comparatively exactly.

本文针对某5.56mm自动步枪在工作中出现断壳的问题，分析了弹壳在轴向拉力作用下的应力应变；基于弹塑性力学及接触理论，建立了弹壳弹膛系统的数学、物理学模型，在通用有限元ANSYS软件的参数化建模工具APDL平台上，建立了弹壳弹膛系统的参数化模型；采用非线性有限元法计算了弹壳弹膛系统的整体应力，引入接触单元法分析弹壳和弹膛的接触压力，探讨了在不同的摩擦系数和不同的闭锁间隙对弹壳弹膛静、动态响应的影响；本文进行了大量的尝试，最后确定采用热、结构耦合单元Plane13，在计算中加载了火药气体的温度历程，成功的获得了弹壳弹膛系统在瞬态的热载荷和瞬态的压力载荷同时作用下弹壳弹膛系统的热应力数值解，考虑因素全面，比较真实的反映了弹壳弹膛系统在火药气体压力和热载荷下作用的情况。

Through designing of composition and structure of the bioactive graded coating,innerstress and its distribution in the coating were analyzed and calculated, the resultsshowed that when composition distribution coefficient n was 1.5, a reasonable stressdistribution could be got, that was at the beginning of deposition the suspension containingrichly BG granules was used so that a rich BG granules layer, a good transitional layerbetween BG layer at the bottom and the coating could be obtained at the titanium alloy side,the bottom of the coating; the stress value near the interface and surface and its character,pressure stress or tensile stress, were decided by the character of its composition itself.Changing composition distribution coefficient n could only change the variation tendency ofstress in the coating, but did not change the stress distribution rule in the coating. Thethinner the coating is, the sharper stress variation in the coating is, which does not mean thatthicker coating is better because the thicker the coating is, the little the permitteddeformation of coating is, so the coating thickness should be thinner, for example, about50μm for bending applications, but for applications only bearing pure shear stress, such asroot of tooth implant, the coating can be thicker little, for instance, about 80～100μm. The study on electrification characteristic and electrophoresis deposition of HAand BG granules in aqueous and non-aqueous solution system found that EPD almost didn'toccur in aqueous solution system. However, because HA granules take position charges inabsolute alcohol, a homogeneous EPD be carried out on the cathode titanium alloy slice, but taking negative charge in absolute alcohol the BG granules not be deposited on the cathode. A guided HA crystallizing, 100～300nm, on surface of the BG granules be realized by metathetical reaction, which cover BG granules with HA microcrystals and make the covered BG granules taking position charges in absolute alcohol, sequentially realize the EPCD of the BG and HA granules on the cathode, so it is feasible to make a titanium alloy/BG/HA bioactive graded coating by making use of EPCD technology. The corrosion experiment of rich boron bioglass coating and plasma spray coating showed that split phase, rich boron and rich silicon phase, occurred during its preparation. In basic medium the corrosion behavior of 〓 BG coating showed uniformity corrosion, the corrosion mostly occurred at rich boron phase area, therefore batch formula design of BGshould avoid the occurring of split phase. The corrosion appearance of plasma spray coatingappeared a non-uniform corrosion, mostly occurred at the edge of the laminated HA moltendrops, and emerged an accelerated corrosion tendency, which will easyly lead to corrosioncrackles extending to the interface and the happening of osmotic interfacial corrosion, thatmay be one of the major reasons leading to the coating cracking-off in the later period. Thetesting results of thermal expansion coefficient of 〓 and 〓BG showed the thermalexpansion coefficient of 〓 BG matched with that of titanium alloy better, and 〓 BG couldsinter with titanium alloy into densification enamel layer at low temperature (720℃).

将Ti6Al4V合金在1000℃下进行真空热处理会降低其力学性能，且合金内的V元素会向表面富集，因此，钛合金真空热处理和表面涂层的烧结温度不能过高，即应低于其相转变点；通过对生物活性梯度涂层的组成和结构的设计，分析和计算了梯度涂层内的应力大小和分布，结果表明：对于本研究，当成分分布系数n=1.5时，可以获得较合理的涂层力学性能，即在沉积开始时，采用富含BG颗粒的悬浮液，以便在钛合金侧获得同底层BG有良好过渡的富BG涂层；梯度涂层界面和表面的应力大小、性质由材料组成本身的性质决定，改变成分分布系数，只能改变涂层内应力变化的趋势；涂层的厚薄不影响涂层内的应力分布规律，但涂层越薄，涂层内的应力变化越快，但这并不意味着涂层越厚越好，因为涂层越厚，涂层允许的变形越小，对于应用于弯曲受力部位的涂层而言，涂层应薄一点为好(50μm)；而对于仅纯受剪切应力的部位，如牙根种植体，涂层可适当加厚(80～100μm)；通过对HA和BG颗粒在水溶液体系和非水溶液体系中的带电特性和电泳沉积的研究发现，它们在水溶液体系中很难发生电沉积；在无水乙醇溶液中，HA颗粒带正电，可在阴极钛合金片上发生均匀的电泳沉积，而BG颗粒则带负电荷；利用复分解反应法，可以制得100～300nm的HA，通过诱导HA在BG颗粒表面结晶，可对BG颗粒进行表面包覆，获得了被HA包覆的BG颗粒，改变了BG颗粒表面的带电特性，使BG和HA颗粒在无水乙醇中均带上正电荷，从而实现了HA和BG颗粒在阴极上的共沉积。

It is well known that the large lattice mismatch (16%) and thermal expansion coefficient mismatch between GaN and sapphire substrate are the main origins of TDs. By new growing technique of LEO, we acquired high quality GaN films almost free of TDs. The stress characteristics in GaN films with MLTB growing technique is dependent on growing systems and conditions, and the changes of stress and dislocation density are rightabout; Combining buffer layers of high temperature and low temperature is first developed to growing GaN films with low dislocation density, and the mechanism of lowering TDs density is that the first buffer layer of high temperature can make nuclear in second buffer layer of low temperature bigger. This technique also can restrain yellow luminescence effectively.

众所周知，晶格失配和热应力失配是GaN异质外延中位错产生的主要原因；为此，我们对几种降低缺陷的MOCVD外延生长方法进行了新的尝试，其中尝试了侧向外延生长技术，得到了低位错密度（小于10〓/cm〓）、高质量的GaN外延层；尝试多低温缓冲层法，发现材料中的应力特性与生长系统和生长条件有关，材料中的应力与位错密度按相反方向变化；首次尝试高低温联合缓冲层法，材料中高温缓冲层可以使随后的低温缓冲层中成核颗粒增大，从而导致随后高温GaN外延膜中位错密度降低，并且能够有效地抑制黄光峰。

The drained behavior of Hokksund sand under low confining pressure was studied through static triaxial test, and the samples were prepared through the dry sedimentation method. The test results were corrected through the membrane effect which is often neglected under high confining pressure, the correction to axial stress for dense sample under a cell pressure of 10 kPa is equal to 12%.

采用干样沉降法制备样品，选用静三轴仪对松砂和密砂样在10kPa 至100kPa的低围压下的排水行为进行了实验研究，并对实验结果作了橡皮膜校正，在围压为10kPa的密砂实验中，轴向应力的校正值可达到12%。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。