变化系数

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。

The effects of microburner dimensions, heat conductivity and thickness of wall, external heat losses and wall roughness on com-bustion characteristics were studied.

模拟结果显示，燃烧器内径的变化、壁面导热系数、对流换热系数和壁面厚度的变化影响了热量在壁面内的传递和流体内径向温度的传递，使得燃料点燃和燃烧稳定性受到影响，甚至导致燃烧停止。

In this paper, the stress and strain fields of lithosphere in Himalayan Western Syntaxis orogenic belt and its adjacent areas since 10Ma are investigated through using the 3-D finite-element simulation, and deformation and evolution process in former 2Ma are simulated with different rheological parameters and rheological structure. Studies on functions in simulation process of different viscosity parameters, constitutive relation and changes of initial curst thickness show below results:(1) When various viscoelastic models are adopted, the selection of the coefficient of viscosity in the Western Syntaxis area has important influence on the its uplifts and evolutions. The computational results show that the viscosity in the Western Syntaxis area should be smaller than 1023Pa·s;(2) When the elastic model is adopted in relatively rigid Tarim basin, obvious changes are induced to the stress and strain fields of the whole Western Syntaxis area;(3) The existence of mechanical property stable block doesn′t make the propagation of the stress field show obvious decoupling phenomenon.

用数值模拟的方法探讨了自10 Ma以来喜马拉雅弧形造山带的西构造结及邻区岩石圈的形变和位移变化特征，并采用不同的流变参数和流变结构模拟了前2 Ma内的形变和应力场的演化过程，通过对不同黏性系数、本构关系和初始地壳厚度的改变在演化过程中所起的作用研究表明：（1）采用黏弹性模型时，西构造结区黏性参数的选取对西构造结及邻区隆升高度和隆升范围有重要影响，计算结果给出西构造结区地壳黏性系数应小于1023Pa·s；（2）相对刚性的塔里木盆地采用弹性结构时，对整个西构造结区域的应力和应变场均能引致明显变化；（3）力学性质稳定块体的存在并没有使应力场的传播出现明显的解耦现象。

The difference of bulk density of coastal soils took an effect on infiltration rate and diffuse rate. The infiltration rate and diffuse rate of coastal soils which bulk density was small were big. The water transmitting experiment of coastal soils showed that the saturated conductivity of different layers in soil profile were great, and the saturated conductivity of undisturbed soil was highly higher than that of disturbed soil. The saturated conductivity of coastal soils embanked earlier was lower than that of coastal soils embanked later. Under different water content, the unsaturated conductivity of coastal soils had a great change and the bulk density had an effect on unsaturated conductivity. The soil with a low bulk density had a high unsaturated conductivity. Chlorine ion moved in coastal soil was an inert ion. The distribution of CU in soil was definite and repeated, which is no relation with the time and velocity of infiltration. The concentration of infiltration solution and the texture of coastal soils had no apparent effect on solute movement synthetic dispersion coefficient, while bulk density took an apparent effect on solute movement synthetic dispersion coefficient. Synthetic dispersion coefficient of coastal soils increased as bulk density decreased.

浙江大学硕士毕业论文浙北海涂土壤水分特性及溶质运移模拟研究 4、海涂土壤的导水能力强，且土壤剖面备土层的饱和导水率变化大，原状土的饱和导水率远大于扰动土的饱和导水率，围垦时间较早的海涂土壤的饱和导水率较围垦时间晚的海涂土壤的饱和导水率要小；不同含水量下的非饱和导水率变化范围很大，最大值与最小值差距可达 10'③ 5、容重的不同对入渗率、扩散率、非饱和导水率都有影响，容重小，入渗率、扩散率、非饱和导水率也花 6、在海涂土壤中运移的氯离子是一&惰性离子&，氯离子在土壤运移过程中的分布有一定的确定性和重现性，与入渗时间和入渗速度无关，溶质运移过程中，入渗溶液的浓度和海涂土壤的质地对溶质运移综合扩散系数DSh无明显影响，而土壤容重对溶质运移综合扩散系数DSh有影响，容重小，DSh大。

The curvature radius and vehicle speed effects were analyzed based on the dynamic amplification factor of a curved-bridge considering the traveling eccentricity of vehicles.

内力和位移的动力放大系数对曲率半径的变化的敏感性各不相同，当曲率半径小于某个特征值后，动力放大系数变化很大。

These influences can be divided into two states: friction and block interference. Based on the data of interference of bicycles on vehicles' driving in typical road section in Beijing, this paper quantitatively analyzes the velocity changing tendency of vehicles under different interference, velocity distribution frequency, and critical transformation of different interference state. The friction and block interference coefficients are also worked out, which are useful to compare interference degrees under different road conditions.

文章将自行车对机动车的影响划分摩擦干扰和阻滞干扰两种状态，通过采集北京市三个典型路段的混合交通干扰数据，定量分析了不同自行车干扰状态下机动车速度的变化趋势，以及速度分布频率，定义并计算了干扰状态相变的临界点：干扰变化阀值，进一步计算了可对不同道路条件下干扰程度进行比较的摩擦干扰系数和阻滞干扰系数。

The c lassi licatioii of the cotton cul Ii vars L1S1 ng the I Inweighted Pair梘roup Method with Arithmetic Average based on the pair Si m i Ian K coe the ieiits IS mostly consistent ~ ithi k iiown pedigree i ri formation and breeding experience.

亲本、r。和 h－二类遗传群体中，铃数每变化个标卅单位快皮棉产是平均改变的标推单什大于铃重和衣分，衣分变化对皮棉产晨的影响又大于铃重；衣分和铃数之问对皮棉产良的间接通径系数为正伯，而他们通过铃重的间接通径系数为负值。

The effect of solid lubricants including polytetrafluoroethylene and graphite on the friction and wear behavior of the composites was examined on the same test rig as well.

结果表明：碳纤维使聚醚砜的摩擦磨损性能得到明显的改善，春改善程度同碳纤维的长度和体积分数相关；当碳纤维的体积分数约为15％时，聚醚砜复合材料的摩擦系数及比磨损率最低；添加固体润滑剂可以使复合材料的摩擦磨损性能得到进一步改善；随着温度及外载荷的变化，摩擦系数及比磨损率表现出不同的变化趋势。

Through this method,the integral gain varies with the average phase shift between tip speed ratio and power coefficient.

针对传统最大功率点追踪极值搜索法固定积分增益存在的不足，依据不同积分系数对系统的影响，提出了一种MPPT变增益极值搜索法，使积分增益随叶尖速比和功率系数之间平均相位移的变化而变化。

It is found that the position of vortex shedding is different fro m three-row cylinders. The time-mean pressure coefficient along the surfaces o f the cylinders is not changed with the void friction. But the fluctuating press ure coefficient reduces with the increase of void fraction.

试验结果表明：沿圆柱表面周向的旋涡分离点随着流动向深层发展，并向圆柱的背部移动；圆柱表面沿周向的时均压力系数几乎不随含气率的变化而变化；圆柱表面的脉动压力系数随着含气率的增加而减小。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。