截面

The instructive conclusion was: 1 under the vertical loading, the shear-lag effect was produced badly, more severer under concentrated loading than under uniform loading .2 the longitudinal bending deformation of the beam flange was true of the imitating plane assumption of deformation . 3 the width length ratio was confirmed as the first factor working on the shear-lag effect among all the geometric parameters;4 the shear-lag coefficient of simple-supported box-girder was severer than the continuous box-girder, the shear-lag effect in the inner supported section of continuous beam was much more severer, we need paying more attention for it in designing. 5 the non-liner characteristics of material deformation have littlie influence on shear-lag effect in BGCW. 6 the experiential calculating formulation and calculating diagram for the effective flange width was raised with the only factor of the width-span ratio., but the primary location of axis of bending moments should not be changed while calculating the inertial moment .

研究认为：1室内模型试验和空间有限元分析结果均表明波形钢腹板组合箱梁在竖向荷载作用下，翼板出现了典型的纵向应力剪滞效应。2在竖向荷载作用下，截面高度上各点纵向正应变分布认为可符合"拟平截面假定"，以此作为波形钢腹板组合箱梁抗弯计算的基本假定。3箱梁宽跨比是影响波形钢腹板组合箱梁翼板剪滞效应的主要因素。4连续波形钢腹板组合箱梁的翼板剪滞系数大于简支梁，且连续箱梁内支点截面翼板剪滞效应相当严重，对此需十分重视。5当混凝土翼板受力由弹性阶段进入弹塑性阶段时，材料的非线性特性对翼板的剪滞效应影响甚微。6提出了根据组合箱梁的宽跨比参数来计算翼板有效宽度比的经验公式和计算图表，但箱梁截面抗弯惯性矩的计算不应改变原先的截面中和轴位置。

In order to testify our whether correction to Rossi's exchange term andthe potential of electron and nucleus is reasonable, we calculate 〓 moleculeelastic differential scattering cross section by electron impact on 100eV, ourresult is obviously better than Rossi's. Then we calculate elastic differentialscattering cross section at 150eV. In order to check the program thatcalculates molecule excitation cross section by electron impact, we calculatehydrogen excitation cross section from ground state to 〓 state at 20eVand 30eV, oxygen excitation cross section from ground state to 〓 state at15eV and 20eV. These calculations are in agreement with other theoreticresults, and experiment measure. Finally, we calculate sulfur moleculeexcitation〓 cross section by electron impact at5eV,7eV,9eV, 11eV, 13eV,15eV, and draw curve of excitation total crosssection corresponding to incident electron energy.

为了核对我们修改的计算激发态的程序是否正确，计算了电子与氢分子碰撞从基态激发到〓态入射能量分别为20eV和30eV时的微分截面以及电子与氧分子碰撞从基态激发到〓态入射能量分别为15eV和20eV时的微分截面，与别人的理论计算结果、实验的测量值基本一致，最后计算了电子与硫分子在5eV、7eV、9eV、11eV、13eV、15eV时的碰撞激发〓截面，作出了电子的入射能量与激发总截面的关系曲线，找出了总截面最大时对应的电子入射能量大约是11电子伏。

Combining with the National Natural Science Foundation ofChina(No.50478032), following researches were done in this thesis: 1 The variation regularity of the ultimate anti-bending capacity of therectangular-sectioned beam with different corrosion has been obtained through thequalitative analysis of 48 beams (32 corroded beams and 12 comparing beams) withaccelerated corrosion; 2 The conclusion has been obtained that the strain of corroded steel bar andconcrete no longer fit in with the assumption of plane section through the analysis ofthe strain data, the strain relation of steel bar and concrete in the mid-span section ofvariously corroded beams at ultimate has been obtained. Through the building of newgeometric relation, the expression of the height of compressive area in the corrodedbeam with rectangular section has been deduced, and the formula with corrosion rateas the main variable for the anti-bending capacity of the corroded concrete beam hasbeen suggested and verified by experiment.; 3 The influence of steel bar corrosion and the concrete regression to the flexureductility coefficient of the corroded structure component has been analyzed. Based onthe relation of steel bar and concrete at yield and ultimate, the expression for theflexure at yield and ultimate of corroded reinforced concrete beam, and the model forthe calculation of the flexure ductility has been built.

本文结合国家自然科学基金项目(50478032)"既有钢筋混凝土桥梁时变可靠度研究"，主要进行了以下研究工作： 1通过对48根快速锈蚀钢筋混凝土矩形截面梁(32根锈蚀梁和12根对比试验梁)数据的定性分析，得到了不同锈蚀率下，锈蚀钢筋混凝土矩形截面梁极限抗弯承载力的变化规律； 2通过对应变数据的分析，论证了锈蚀构件钢筋和混凝土的应变不再符合平截面假定的结论，并通过回归分析得出了不同锈蚀率的螺纹钢筋梁和光圆钢筋梁在极限弯矩作用下，跨中截面处钢筋应变和钢筋处混凝土应变的关系，通过构造新的几何关系，得出了锈蚀钢筋混凝土矩形截面梁计算受压区高度的表达式，既而得出了以锈蚀率为主要变量的锈蚀钢筋混凝土矩形截面梁的正截面抗弯计算建议公式，并通过试验数据加以验证； 3分析了钢筋锈蚀和混凝土劣化对锈蚀构件曲率延性系数的影响，结合钢筋屈服和极限弯矩两种状态下钢筋和混凝土的应变关系，分别得到了锈蚀钢筋混凝土矩形截面梁屈服曲率和极限曲率的计算表达式；既而推导出曲率延性系数的计算模型。

It is found that both the total and differential cross sections increase with the increasing of screening interaction, and especially for energies below 10 keV/u, the cross sections are one to two magnitudes larger than those in the unscreened case.

研究发现，碰撞电离总截面随等离子屏蔽的增加而增大，特别是在10 keV/u以下的低能区电离截面有量级的增加。对随能量变化的一阶微分截面，在低能碰撞过程中，屏蔽作用增加，微分截面呈量级增加，高能碰撞微分截面呈倍数增加。

C arbitrarily inequiaxial T-shaped, L-shaped and "十"shaped columns subjected to 792 load conditions is calculated using compiled C++ programme. On the basis of calculation results, the factors influencing the worst load orientation are analyzed and load orientation of the least curvature ductility of three kinds of sections is presented.Furthermore a analysis of failure mechanism for R.

本文采用非线性全过程分析方法，采用C++语言编制了不等肢异形柱截面曲率延性比的计算程序，首先计算了不等肢T形、L形和十字形柱在792种工况下的截面曲率延性比，在此基础上分析了影响不等肢异形柱截面延性的最不利荷载方向的各种因素，并得出了这三种截面不等肢异形柱在上述工况下的截面延性最不利荷载方向。

The results show that the radiative properties of randomly distributed soot aggregates for a given fractal dimension are complex functions of the monomer diameters, the number of monomers in the aggregates,and the refractive index; For a small value of the monomer diameters, the absorption cross section of soot aggregates tends to be relatively constant when the fractal dimension is small but increases rapidly when the fractal dimension exceeds two. However, a monotonical reduction in light absorption with the increase of the fractal dimension is observed for soot aggregates with sufficiently large monomer diameters, number of monomers,and refractive index. The scattering cross section , extinction cross section and single-scattering albedo increase monotonically with the increase of the fractal dimension. Overall, the results for soot aggregates differ profoundly from those calculated for the equivalent spherical particles, and the discrepancies between them will change small with the increase of the fractal dimension.

研究表明，在给定分形维数的情况下，烟尘団簇粒子的辐射特性取决于原始微粒粒径、数量及复折射率；原始微粒较小的団簇粒子，当分形维数较小时，吸收截面变化不明显，但当分形维数大于二时，吸收截面骤然增大，然而，对于具有比较大的原始微粒粒径、数量及复折射率的烟尘団簇粒子，吸收截面随着分形维数的增大而单调递减；随着分形维数的增大，団簇粒子的散射截面、消光截面及单次散射反照率均单调递增；从整体上来讲，団簇粒子的辐射特性与等效球形粒子的辐射特性存在着比较大的差别，并且这种差别随着分形维数的增大而减小。

The results show that increasing the ball numbers and mandrel extension length may reduce the ovalization, but leads to more remarkable wall thinning; the ovalization becomes more severe with the larger bending angle; the smaller the relative bending radius, the larger the ovalization is; the ovalization and wall thinning degrees are both smaller in the case of pressure die with dry lubricant; and under the same bending condition, the ovalization of LF2M tube is larger than the one of 1Cr18Ni9Ti tube.

结果表明，增加芯头个数与芯棒伸长量都能减小弯管的截面畸变，但两者都导致弯管壁厚减薄量增大；随着弯曲角度的增加，截面畸变越严重，相对弯曲半径越小，无芯棒与芯头支撑段弯管的截面畸变愈严重；在压块无润滑情况下，弯管的截面畸变和壁厚减薄量都小，并且在同等弯曲条件下，1Cr18Ni9Ti弯管的截面畸变小于LF2M弯管。

It is widely employed in many industrial domains. The most attractive domain of ring rolling technology is to roll the rings with specially-shaped cross section directly. But the rolling deformation law of ring with specially-shaped cross section is more complicated compared with rectangle section ring and in the process there are lots of special phenomenon such as underfilling, shrinking-drawing, concave, saucer shape and etc.

环件轧制技术最有吸引力的领域和发展方向是直接轧制成形截面轮廓复杂的异形截面环件，然而，与矩形截面环件相比，异形截面环件轧制成形规律更复杂，轧制过程中常常出现截面轮廓充不满、拉缩、凹坑、碟形等各种特有现象，这些现象是异形截面环件轧制成形规律的客观反映。

In the direction of flow between the first cross section (50) of flow and the second cross section (52) of flow, a third cross section (54) of flow is formed between the valve member (40) and the valve housing (36), said third cross section (54) of flow being larger than the first cross section (50) of flow and the second cross section (52) of flow.

在流动方向上在第一通流横截面(50)与第二通流横截面(52)之间在阀元件(40)与阀壳体(36)之间形成第三通流横截面(54)，该第三通流横截面大于第一通流横截面(50)和第二通流横截面(52)。

The main research contents are as follows:1. Through massive calculation, analysis and comparison, sum up the similarities and differences between the special-shaped cross sections and rectangular cross sections in mechanical features, between reinforced concrete special-shaped columns and rectangular columns in load-bearing capacity, ductility performance and provide necessary basic concepts and data for further understanding the characteristics of the special-shaped columns;2. Through massive elastic calculations and elasto-plastic analysis, under the preconditions of satisfying the code's requirements for axial compression ratio, limit value of lateral displacement and load-bearing capacity of normal section,oblique section and beam-column joint, under circumstances of different intensity of earthquake, structure dead weight, sort of site and column grid bay dimension, the variation regularity of maximum suitable height of structure, and thus sum up the maximum suitable height of structure for code for the purpose of macro-control while deciding the design scheme;3. Make a preliminary study on the stress feature of reinforced concrete special-shaped column and Z-shaped column of which the ratio of limb length to limb thickness is between 4~5 ,and the preliminary design method is suggested;4. Through elato-plastic time history dynamic analysis of typical projects, check up the weak storey of the special-shaped column structure and yielding, breaking and collapse mechanism to satisfy the earthquake resistant requirement to buildings of remaining stand under strong earthquake;5. Derive for project use simplified calculation formula of vibration period, suitable vibration period, suitable rigidity of special-shaped column structure through theoretical analysis, and provide an easy and practical method for deciding the structure scheme economically, safely and reasonably;6. Based on the study achievements in theory and massive analysis and calculations of this paper, sum up the regularities of inner force, deformation of special-shaped column structure and seismic conceptual design, and thus the suggection of seismic design of special-shaped column structures is presented.

本文研究的主要内容如下：通过大量的计算、分析和对比，总结出异形截面与矩形截面在力学特性、钢筋混凝土异形截面柱与矩形截面柱在承载能力、延性性能等方面的异同，为深入了解异形截面柱的特点提供必要的基本概念和数据；通过大量的弹性及弹塑性计算分析，在满足规程对轴压比、侧移限值及正截面、斜截面、节点承载力抗震验算要求的前提下，在不同抗震设防烈度、结构自重、场地类别及柱网开间尺寸情况下最大适宜高度的变化规律，并在此基础上总结归纳出异形柱结构的最大适用高度规定，可用于规程，以便于在确定方案时起到宏观控制的作用；对肢长与肢厚比在4～5的钢筋混凝土异形截面柱及Z形柱的受力特点进行初步探讨，提出初步的设计方法；通过对典型工程的弹塑性动力时程分析，检验异形柱结构的薄弱层及屈服、破坏、倒塌机制，以达到建筑物大震不倒的抗震设防要求；通过理论分析，推导出异形柱结构自振周期，以及适宜自振周期、适宜刚度的工程实用简化计算公式，为经济、安全、合理地确定结构方案提供简便实用的方法；在本文理论分析、计算以及大量的研究成果基础上，总结归纳出异形柱结构内力、变形的规律及抗震概念设计内容，并在此基础上提出异形柱结构的抗震设计建议。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。