查询词典 diffusion equation

By making use of multi-points backward pressure of one dry gas well, this paper introduces how to confirm dynamic friction coefficient of downhole tubing at the exact moment through stable testing material, gives the productivity and the corresponding bottom hole pressure by using productivity equation, calculates wellhead pressure in combination with dynamic friction coefficient of tubing, establishes the correct wellhead outflow performance equation for this well, draws out wellhead outflow performance curve and discusses how wellhead outflow performance equation or wellhead outflow performance curve changes with the decrease of formation pressure or the change of wellhead outflow performance curve.

借助1口干气井的多点回压法试井资料，介绍了如何利用气井稳定试井资料，确定该气井此时此刻井下油管动态摩阻系数；利用产能方程给出产量和对应的井底压力，结合油管动态摩阻系数计算井口压力，建立该井准确的井口流出动态方程并编绘井口流出动态曲线；讨论了随着地层压力递减和井下油管动态摩阻系数变化规律，井口流出动态方程或井口流出动态曲线的变化规律。

An equation which is true only for certain value of a letter in it,or for certain sets of related values of two or more of its letters,is an equation of condition ,or simply an equation.

一个等式若仅仅对其中的一个字母的某些值成立，或者对其中两个或多个字母的若干组相关的值成立，则他是一个条件等式，或简称方程。

In this paper, we invert the condition equation into a complete nonlinear partial differential equation, and study some properties of the solution of this equation from a theoretical point.

本文把其条件方程转化为一个非线性偏微分方程，从理论角度探讨了一下此方程的解的一些性质。

Then the stationary joint probability density, the conditional reliability function, the mean first-passage time of the optimally controlled system are obtained from solving the reduced FPK equation, the backward Kolmogorov equation and the Pontryagin equation, respectively of fully averaged systems.

求解与之相应的Fokker-Planck-Kolmogorov方程得最优控制系统的联合概率密度，进而求得最优控制系统的平均幅值；求解与之相应的后向Kolmogorov方程得最优控制系统的条件可靠性函数，进而求得首次穿越时间的条件概率密度；求解与之相应的Pontryagin方程得最优控制系统的平均首次穿越时间。

Then the FPK equation governing the joint probability density of amplitude and phase, the backward Kolmogorov equation governing the conditional reliability function, and the Pontryagin equation governing the mean first passage time are established, respectively.

随机微分方程。在此基础上，建立联合概率密度满足的Fokker-Planck-Kolmogorov方程、条件可靠性函数满足的后向Kolmogorov方程以及平均首次穿越时间满足的Pontryagin方程，分别求解这些方程得到联合概率密度、条件可靠性函数以及平均首次穿越时间。

On the basis of analyzing the lilnitations of the conventional flow equation for rotameter , ac-cording to principle of mechanical energy conservation and transform for real fluid, a new generalflow equation Q=for rotameter has been developed.This equation includes the rota-form factor β to reflect the influence of rota-form on flowmeasurement.

在分析转子流量计习用流量方程局限性的基础上，根据实际流体机械能守恒与转换原理，定义了反映转子形状特征对流量测定影响的转子几何形状因子β；经过推导，最终获得了转子流量计一种新的普遍流量方程Q＝。

Thirdly, we should start with momentum equation and equation of continuity. They offer theory basement through equation dispersion, interpolation of disheveled datas and analysis of turbulence coefficient.

再者，从动量方程和连续方程入手，通过方程的离散、散乱数据的插值、紊动粘性系数等的分析，为数学模型的建立提供理论基础。

This paper starts from the rules of Coulomb's law, Ampere's power Law and the D'Alembert equation, hai Muhuo equation and so on, reveals the mechanical essence and divergent characteristic of electromagnetic interaction; it follows the rule shown in d'Alembert equation and transmits in the form of electromagnetic waves and spherical waves in electromagnetic field.

文章从库仑定律、安培力定律和达朗贝尔方程、亥姆霍次方程等规律出发，揭示了电磁相互作用的力学实质和发散特性；它遵循达朗贝尔方程所示的规律，以电磁波的形式和球面波的方式在电磁场中传递。

When propagating light\|ray passes through two fixed points in the gradient index mediums and a cuspidal variable\|point （at this point the trace equation of propagating light\|ray is non\|differentiable） at the borderline of two different GRIN mediums, the mathematical relationship, which the trace equation of propagating light\|ray and borderline equation of two different GRIN mediums should satisfy, is derived by the Fermat's principle and calculus of variation.

当光线通过梯度折射率介质中两个固定点和两个GRIN介质界线上的可动尖点（光线轨迹方程的不可微点）时，由费马原理和变分法运算推得传输光线的轨迹方程与两种不同GRIN介质的界线方程应满足的微分关系式。

On the basis of the thermal balance equation,specific inner work equation,cyclic heat absorption equation of a thermal system and the standard coal-consumption calculation formulae of power generation,derived was a general calculation model featuring the influence of lower terminal temperature difference of a heater on the coal consumption of a power plant.

根据热力系统热平衡方程、比内功方程、循环吸热量方程及发电标准煤耗率计算公式，导出了加热器下端差对机组煤耗影响的通用计算模型；并且在考虑到加热器下端差的影响的基础上，改进了以往的建模方法，得到了更为完善的加热器上端差对机组煤耗影响的通用计算模型。

Sodium citrate; calcium carbonate; calcium hydroxide; potassium bicorbonate; magnesium carbonate; ferrous sulphate; Zinc sulphate; copper sulphate; manganese sulphate; potassium iodide; sodium selenite.

柠檬酸钠；碳酸钙；氢氧化钙；碳酸氢钾；碳酸镁；硫酸亚铁；硫酸锌；硫酸铜；硫酸锰；碘化钾；亚硒酸钠。

All this to say that I'm glad filmmaking hasn't become completely ironic. I can enjoy an ironic film as much as the next person, but they usually involve a message of some sort. One that's delivered in a smirkingly clever way that requires little in the way of talent.

所有这些都是说，我很高兴电影制作没有变成完全讽刺艺术，我可以和下一个人一样享受讽刺电影的乐趣，虽然他们经常会被划归到一定级别，技术方面不需要很高的才能。