空气动力学

Based on gas dynamics,a mathematical model for the air brake system of train is established.

根据气体动力学原理建立了列车空气制动系统的数学模型，预测了制动系统紧急制动作用；陆界长度与机车大闸排气口面积、列车管定压及列车长度的关系。

The complete coupling between the system rigid and flexible degrees of freedom is allowed since the start of the formulation. The Hamilton's principle is utilized in deriving the equations of motion. Both viscous damping and air drag force have been introduced into this model.

该模型考虑了轴承摩擦阻尼和柔性梁结构阻尼以及空气产生的风阻，并采用一致的方法将阻尼和末端质量的影响引入到动力学方程中。

The theory analysis in allusion to the direction framework of a kind of air suspension is processed taking use of Langrate method of the multi-body dynamics theory. At the same time the kinematics analysis of rigid body and elasticity is also processed based on Virtual Prototype Technique which is popular in the world and the changing orderliness of wheel alignment parameters along with wheel jumpiness is got.

应用多体动力学理论的Langrage方法对一种空气悬架的导向机构作了理论分析，并基于国际上流行的虚拟样机技术对其作了刚体运动学和弹性运动学的分析，得到了该型空气悬架定位参数随车轮跳动的变化规律。

HPLC method of determination of CCU has been developed for the kinetic study. The kinetics of photodecomposition of CCU in various carrier gases have been studied. The photoreaction of CCU in nitrogen and air is of the first order, while in oxygen is closer to that of the second order. The rate constants in nitrogen, air and oxygen are 0.00703/h, 0.0109/hand 0.00445 , and the half-livies are 98. 6, 63. 6 and 62. 7hour respectively.

采用以甲醇一水为流动相的反相HPLC作为分析手段，对灭幼脲在不同载气中的光解动力学作了研究，结果表明，灭幼脲在氮气和空气中的光解反应符合一级动力学形式，而在氧气中的光解则更接近于二级反应形式；在三种气氛中的反应速度常数分别为0.00703h〓，0.00109h〓和0.00445h〓〓，半衰期相应为98.6、63.6及62.7h。

A measuring approach of pressure oscillation has been developed and experiments are conducted in a 10 liter two-dimension air-lift loop reactor. The experimental results show that the local mass transfer parameters have close relationship with the operating conditions, the structure of ALR and the properties of the reaction systems. A series of measurements of pressure pulse indicate that a gas distribution zone exists near the gas sparger, and in this zone the responding signals of pressure pulse are different with the signals measured in other parts of the reactor.

对不同结构的环流反应器的局部流体动力学和传质动力学特性进行了研究，利用压力传感器测量了空气-水、空气-NaCl水溶液、空气-Na〓SO〓水溶液、空气-葡萄糖水溶液和空气-乙醇水溶液五种体系，在不同气速下，不同位置的压力脉动信号，通过随机信号的数学分析，得到压力脉动信号的频谱特性，并依据压力脉动信号的频谱特性的分析给出环流反应器气体分布区的范围。

The thermal decomposition kinetics of the N , N′-bis(5,5-dimethyl-2-phospha-2-thio-1,3-di- oxan-2-yl)ethylenediamine in air were studied by TG-DTG techniques. The kinetic parameters of the decomposition process for the title compound in the two main thermal decomposition steps were calculated through the Friedman and Flynn-Wall-Ozawa methods and the thermal decomposition mechanism of DPTDEDA was also studied with the Coats-Redfern and Achar methods.

以TG-DTG为手段，研究了 N ， N ′-二(5，5-二甲基-2-磷杂-2-硫代-1，3-二噁烷-2-基)乙二胺在空气中的热分解动力学，利用Friedman法、Flynn-Wall-Ozawa法对DPTDEDA进行了动力学分析，求出了该物质两个主要的热分解阶段的热分解动力学参数，同时利用Coats-Redfern法、Achar法研究了该物质的热分解机理。

Based on the analysis of kinetical process of CH4 -air oxidation, a numerical modeling of the species concentrations and temperature for CH4 jet diffusion combustion is made using a four-step reduced mechanism and two semi-detailed chemical kinetical reaction mechanismsW mechanism and Y mechansim.

在分析甲烷-空气氧化反应动力学过程的基础上，采用四步简化机理和两种半详细的化学反应动力学机理-W机理和Y机理，对甲烷射流扩散燃烧的组分浓度和温度进行了数值模拟，计算结果与实验结果进行了对比分析。

METHODS The residual concentrations of sodium formaldehyde sulfoxylate in the solutions were determined by iodimetry, the datas were fitted by linear regressions and then ...

在高精度电热恒温箱中在不断通入空气或医用纯氧的情况下，采用碘量法测定甲醛合次硫酸氢钠在水溶液中不同时刻的浓度，作出降解曲线，将测得的数据进行降解动力学方程的拟合并获得动力学参数，并计算反应速率常数。

By regression of experimental data, therules of the linkage between these factors, which will provide a theoretical basis for designing BBP with different scales.3 Using thermal analysis technology and dynamic thermogravimetry, the paper studies combustion kinetic characteristics of 3 types of agricultural crops at different rate of temperature rise, and thus, achieved dynamic parameters of these fuels at different rate of temperature, established dynamic model of straw combustion, which reflects the dynamic process in the fast combustion area.4 Characteristics of straw briquette combustion was experimented, focusing on the impact of straw type, temperature, air supply, and density, diameter, and weight of briquette on the combustion speed, and the following conclusions were drawn:(1) combustion of straw briquette fuel is static permeation diffusion combustion;(2) temperature has a larger impact on the speed of straw briquette combustion than air supply; the higher the combustion temperature is, the faster volatilizable component separates out, and the less steady the combustion is;(3) density of briquette fuel has impact on the speed of volatilizable component separation and therefore the combustion speed;(4) increase of diameter and weight of briquette fuel increases the average combustion speed in the initial stage, and that in the later stages is comparatively steady;(5) the proportion of volatilizable component in straw briquette fuel is high, therefore, the temperature control during combustion under the rational ventilation condition is essential to ensure its safe combustion.5 Using the above-mentioned results of experiments and theoretical analysis, and based on thought of hydraulic driven and bi-direction compression, the hydraulic system and compression parts of the HBP BBP are re-designed in terms of industrialization.

利用热分析技术，采用动态热重实验法，对我国的三大农作物秸秆在不同升温速率下的燃烧动力学特性进行了较系统的研究。得到了各原料在不同升温速率下的动力学参数；建立了秸秆燃烧的动力学模型，该模型反映了秸秆迅速燃烧区的动力学过程。 4 对秸秆成型燃料的燃烧特性进行了试验研究。着重研究了秸秆河南农业大学博士学位论文巫的种类、温度、空气供给量、成型燃料密度、直径、质量对成型燃料燃烧速度的影响并得出如下主要结论：①秸秆成型燃料的燃烧方式属于静态渗透式扩散燃烧。②秸秆成型燃料燃烧速度受温度的影响大于通风量燃烧速度的影响：燃烧温度越高，挥发分析出速度越快，燃烧平稳性愈差。③成型燃料密度影响成型燃料挥发分的析出速度，影响燃烧速度。④成型燃料直径和质量的增加，使得燃烧初期的平均燃烧速度增大，中后期的平均燃烧速度相对平稳。⑤秸秆成型燃料含挥发分比例高，因此合理配风下的控温燃烧是保证其完全燃烧的关键。 5运用已取得的试验和理论分析结果，以液压驱动、双向成型为基础，从产业化的角度对HBP型成型机进行了液压系统和成型部件的改进设计；同时采用了二级预压机构，使该成型机的生产率达到 500kg.hd；单位能耗 60kwh。上'左右，磨损件修复周期 300小时左右，基本解决了影响生物质固化技术在国内推广的技术难题。

Applying finite element method,the dynamic characteristics of drill string with cone bit in straight hole were simulated,and the whirl,deformation and the dynamic stress in air drilling were compared with the ones in drilling fluid drilling .

应用有限元方法，仿真了空气钻井时斜直井眼中带牙轮钻头钻柱的动力学特性，比较了空气钻井和钻井液钻井条件下钻柱的涡动、变形以及动态应力状况，探讨了空气钻井钻柱失效的动力学机理。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。