查询词典 friction coefficient

The highest heat transfer coefficient for air flowing in the nine 3-D IFT with staggered arrangement fins is No9 tube. In the turbulent region, the heat transfer coefficient of No9 tube is a factor of 10.36 compared with smooth tube, and its thermodynamic performance coefficient is as high as 6.49; The average Nusselt number in the most superior 3-D IFT with staggered arrangement can be increased by about 1.04 times in the laminar flow, and 6.38 times in the transitional flow as compared with that in the smooth tube. The friction factor between fluid and tube wall can be 0.96 times in laminar flow, and 12.68 times in transitional flow as compared with that inside the smooth tube.

在进行实验的九根肋叉排三维内肋管中，换热最强的No9管与光管相比，在紊流区的换热强化比平均可达10.36倍，阻力增大比约为4.06倍，其热力性能系数高达6.49；在过渡流区的换热强化比平均可达6.38倍，同时阻力增大比约12.68倍；在层流区的换热强化比为1.04倍，而阻力增大比仅约0.96倍。

By synthesizing theories of systems engineering, science of talent, talent assessment, performance appraisal and bibliometrics, the author analyzes the qualification structure and performance structure of theachers in military academies and sets up a basic structure and concrete appraisal indicator system of qualifications of technical specialty for teachers in colleges. The author puts forward new appraisal indicators such as "lecuring hours coefficient","republication coefficient","thesis of core journals coefficient" and "citation coefficient". Comparatively complete quantification approaches are invented by the author for working performance of teaching, researching and social service of teachers. Based on this, the author establishes an integrated method to generate the appraisal results. By the application of stadardized processing on the appraisal results and synthetization of weighted indexes, the author solves the addibility and comparability problems of differentiated appraisal results by category or dimensiok, and realizes the amalgamation and comprehensive appraisal of inflexible appraisalresults and flexible appraisal results, and probes into the testification methods of validity, consistency and sensitivity analysis for the indicators system.

综合运用系统工程理论、人才学理论、人才素质测评理论、工作绩效评估理论、文献计量学等原理与方法，分析研究了军校教师的素质结构和绩效结构；建立了高校教师专业技术资格评审条件基本结构和具体评价指标体系，提出了"完成主讲课程课时系数"、"著作重版系数"、"核心期刊论文系数"、"论文被检索引用系数"等若干新的评价指标；提出了比较完整的教师的教学、科研、社会服务等工作业绩的量化方法；以此为基础，建立了评价结果的综合方法，通过对评价结果的标准化处理，运用指标加权综合法，解决了不同类别、不同量纲指标的评价结果的可加性和可比较性问题，实现了硬评价结果和软评价结果的融合和综合评价；探讨了指标体系有效性、一致性、灵敏度分析的检验方法。

This study is to give a solution for the estimation of flash point for mixtures, the necessity for classification of flammable liquids. The traditional models for predicting flash point of mixtures usually by the activity coefficient approach. However, the parameters of activity coefficient were regressed from phase equilibrium data in the literatures. If there is no such parameter in literatures for the desired mixture, the model cannot predict the flash point oft hat mixture. Thus, this research aims at the improvement of deficiency of the flash point prediction models in the literatures by useing UNIFAC (Universal Quasi-chemical Functional Group Activity Coefficient) equation, Dortmund-UNIFAC equation and Lyngby-UNIFAC equation. In this study, we were aim at the prediction model for miscible mixtures.From the result, it is suggested to use different type of UNIFAC equation to estimast activivity coefficient in the predition of flash point for different mixture type.

易燃液体分类的主要依据参数为闪火点值，因此本研究目的为解决易燃液体中混合物分类时所面临到的闪火点值缺乏的问题，而在过去文献中所提出的闪火点预测模式会使用到活性系数，但这些模式使用到的活性系数均需要相平衡的数据以回归其所需参数，若所欲估算闪火点的混合溶液文献上未有相关参数，则无法有效利用闪火点预测模式估算其闪火点，因此针对文献中现有闪火点预测模式的缺点，利用描述液体混合物活性系数UNIFAC (Universal Quasi-chemical Functional Group Activity Coefficient)方程式、Dortmund-UNIFAC方程式和 Lyngby-UNIFAC方程式，建立发展一闪火点预测模式，而本研究以互溶溶液为对象。

Diopside crystals in fluosilicate glass-ceramics tend to lower thermal expansion coefficient, while richterite crystals in fluosilicate glass-ceramics tend to increase thermal expansion coefficient.The lowest thermal edpansion coefficient of K2O-MgO-SiO2-CaF2 fluosilicate glass-ceramics is 78.4×10-7(20-300℃), while the highest thermal expansion coefficient of this glass-ceramics is 85.6×

透辉石结晶相的含量增加使微晶玻璃的热膨胀系数降低，与此相反碱镁闪石结晶相的含量增加却使微晶玻璃的膨胀系数增加。K2O－MgO－SiO2－CaF2系统氟硅酸盐微晶玻璃的最小热膨胀系数为：78.4×10－7（20～300℃）；最大热膨胀系数为：85.6×10-7（20～300℃）。

First of all,we have given some of the basic concepts of differential equations, described the constant coefficient linear ordinary differential equation solution, for a class of second-order variable coefficient linear ordinary differential equation initial value problem, an approximate solution, the method is first unknown function of a definition for N sub-interval, and then in between each district within a constant coefficient ordinary differential equations similar to the replacement, the solution has been the problem as similar to the original analytical solution, and then gives a detailed second-order change order coefficient of linear homogeneous ordinary differential equation solution examples, the examples of the approximate method proposed in this paper is valid.

首先给出了微分方程的一些基本概念，讲述了常系数线性常微分方程的解法，针对一类二阶变系数线性常微分方程初值问题，提出了一个近似解法，本方法是先对未知函数的一个定义区间作N等分，然后在每一个小区间内用一个常系数常微分方程近似替换，所得到的解作为原问题的近似解析解，随后详细给出了一个求二阶变系数齐次线性常微分方程的解的实例，该实例说明本文提出的近似方法是有效的。

Chromic trioxide and chromium hemitrioxide are determined with iodometry, the coefficient of variation of chromic trioxide is 0.056%, and the recovery of marked compound is 99.82-99.83%; the coefficient of variation of chromium hemitrioxide is 1.45%,and the recovery of marked compound is 98.55-99.26%; iron is determined by complexometric titration, the coefficient of variation of iron is 1.73%, and the recovery of marked compound is 99.12-99.23%;sulfate is determined by complexometric titration, the coefficient of variation of sulphate is 0.16%, and the recovery of marked compound is

Analysis Of The Chromium Electroplating Wastewater By Oxidation-reduction And Complexometric Titration-化学工程与工艺-本文采用氧化还原滴定法与络合滴定法对镀六价铬的废水中铬酸酐，三氧化二铬，铁和硫酸根的含量进行了测定：铬酸酐和三氧化二铬用碘量法测定，铬酸酐的变异系数为0.056%，加标回收率为99.82-99.83%，三氧化二铬的变异系数为1.45%，加标回收率为98.55-99.26%；铁用络合滴定法测定，其变异系数为1.73%，加标回收率为99.12-99.23%；硫酸根用络合返滴定法测定，其变异系数为0.16%，加标回收率为

By carrying out the experiment of eight pieces of brick masonry walls with pilaster strengthened with glass fiber reinforced polymer and one piece of normal masonry wail with pilaster, the influence coefficient of pilaster, modified coefficient, statistic coefficient and effective participation coefficient are brought forward theoretically.

通过对1片未加固带壁柱墙体和8片玻璃纤维复合材料加固带壁柱墙体抗震试验的结果，在理论分析的基础上，给出壁柱影响系数、间接抗震抗剪承载力修正系数、统计系数和有效工作系数的表达式。

The elements of optical waveguide strain-stress measurement and fiber bragg grating strain-stress measurement system based on wavelength division multiplexing and spatial division multiplexing are emphatically discussed; the displacement regularity of stress field induced by roadway group excavating and short wall mining process is analyzed in detail; the concept of roadway "equivalent radius","correcting coefficient of coal and rock mass mechanical parameters",and "mining affecting coefficient" is put forward; the calculation method of "equivalent radius", the method of inversion of "correcting coefficient of coal and rock mass mechanical parameters", and the "mining affecting coefficient" determination method with the field measurement results and so on are provided.

重点研究了光波导应力应变测量原理，以及基于波分复用和空分复用技术基础上的布拉格光纤光栅应力应变测量体系；详细分析了近距离巷道群开掘工作和短壁体系回采工作诱发的应力场的重新分布规律；提出了巷道"当量半径"、"煤岩体力学参数修正系数"、"采动影响系数"等概念；给出了"当量半径"的计算方法、"煤岩体力学参数修正系数"的反分析求算方法、以及通过现

Determined by the specific geological background of Longhetun, the characteristics of the soil resources show abundant calcium and leaning to alkaline. Monomial indexes to evaluate the revisal coefficient of soil adapted to karst mountains areas were screened out combined with the function of karst dynamics system and analysis of characters of each factor about fertility in soil. Predigestion model to soil revisal coefficient monomial assessment was established by successful importation of the content of nutrition elements in plant body, latent efficient elements in soil and available thickness of soil in the cranny of epikarst according to the characters that three carriers of soil, soil water and karst water supply nutrition to plants and two layers of foundation consist of surface soil and soil in epikarst cranny, and several types of soil revisal coefficient and weather-soil productive potentiality were calculated, the results show that the soil revisal coefficient was even more practical after modification than before, which make up of innovation of this study.

龙何屯特殊的地质背景条件决定了耕地土壤资源的富钙偏碱的特点，结合岩溶动力系统的作用，系统分析土壤中各肥力因子的特点，筛选出适宜岩溶石山区特点的土壤订正系数评价单项指标，针对研究区存在土壤、土壤水、岩溶水三种载体提供植物营养和表层土、土下表层岩溶带裂隙土两层空间基质的特点，成功引入植物体内营养元素含量、土壤元素隐性有效态含量及土下表层岩溶带裂隙土有效厚度等新参数指标，探讨建立了土壤订正系数单项指标评价简化模型，计算出龙何屯各耕地类型土壤订正系数和气候-土地生产潜力，结果显示修正后的土壤订正系数比修正前更符合实际，成为本研究的创新点。

Designed the sensitivity algorithm that is based on dc tide, built mathematical model; to give out the definition of a few kinds of sensitivity coefficient and computation are formulary, if power transmits distributinging coefficient , spur track leaves to distributing coefficient and spur track leave to transmit distributinging coefficient .

梗概： 设计了基于直流潮流的灵敏度算法，并建立了数学模型；给出了几种灵敏度系数的定义及计算公式，如功率传输分布系数，支路开断分布系数和支路开断传输分布系数。

Now he worked in ajoint venture.

现在他在一家合资企业工作。

More troops in Afghanistan won't change any of the foregoing.

更多的在阿富汗的军队也不会改变之前的状况。