扩散

Based on the theoretical framework of the leakage and spread of such poisonous and harmful substances as glycol and acraldehyde, this paper advances the graphic simulation of GIS of poisonous and harmful substances.

以石化企业乙二醇、丙烯腈装置产生的有毒、有害物质泄漏、扩散和污染范围的理论模型为根据，提出有毒、有害物质的地理信系统扩散图形模拟方法。

The so-called "adiabatic expansion" means that the light generated by the acoustic signal in the absorption within the region transit time under the same conditions are far greater than the time required for thermal diffusion, negligible effect of the proliferation of light signal the impact of this Conditions, acoustic imaging to short-pulse laser for excitation, ultrasonic signal for the information to the carrier, with high-resolution and high-contrast imaging features.

所谓的"绝热膨胀"是指所产生的光声信号在吸收区域内的渡越时间远远大于相同条件下热扩散所需的时间，可忽略热扩散效应对光声信号产生的影响，在此条件下，光声成像以短脉冲激光为激励源、以超声信号为信息的载体，具备高分辨率和高对比度的成像特点。

It is unbelievable that the Indian State has not punished the Chinese for adventurism, for instance by proliferating to Taiwan, Japan, or Vietnam, just as China has proliferated nuclear weapons and missiles to North Korea and Pakistan.

不可思议的是，印度居然没有惩罚中国的冒险主义，比如通过扩散到台湾、日本或越南，就如同中国把核武器和导弹技术扩散到北朝鲜和巴基斯坦一样。

This article described the principle of the DTI and its usage in diagnosis of brain tumors,providing information before the operation of the brain tumor,and in diagnosis of the callosal agenesis.

本文就扩散张量成像技术的原理、扩散张量成像对颅脑肿瘤术前计划制定，以及对颅脑肿瘤、先天性胼胝体发育不全等多种疾病诊断价值的研究进展做一综述。

Because of the exotic weeds with strong reproductive capacity, adaptability and adversity-resistance, and short of strong competitive plants and natural enemies in the local area the exotic weeds such as Aiternanthera philoxeroides, Eichhornia crassipes, Ageratina adenophorun and Ageratum conyzoides etc.

由于农林牧渔业生产、绿化美化等目的有意引进；或旅游、交通工具等无意引入；或自身扩散传播的自然入侵，外来植物一旦逃逸人为控制进入自然生态系统并能自行繁殖和扩散，形成野化种群，变成外来入侵植物，成为危害农牧业生产和破坏生态环境的有害杂草。

An adaptive grid scheme controlling cell area is used to generated grids in the divergent section of symmetric annular nozzle, and the generated grids are used in the flowfield calculation through the uncoupled way. The elliptic equations are used to generate grids in three dimensional regions of FDN divergent section, the source terms used in the equations employ a mathematical form which is independent of the boundary shape and of the boundary grid point distribution, the free parameters contained in the source terms are determined by the two restraint conditions, the intersection angle of transverse grid lines with boundaries and the local curvature of the transverse grid lines at the boundaries, and the interior grid distribution controlled directly by the grid point distribution assigned on the boundaries is realized, it makes the grid more clustering near the nozzle wall. For the generated grids in the whole computational regions have a good smoothness and orthogonality, the accuracy of calculation in the flowfield is ensured.

对轴对称的环形喷管采用控制网格面积的自适应网格方法对扩散段部分进行了网格生成，并通过非耦合方式应用于喷管的流场计算中；对强制偏流喷管扩散段内的三维区域采用椭圆型方程进行网格生成，方程中的源项采用了与边界形状和边界网格点分布无关的数学形式，源项内的自由参数由横向网格线与边界的交角及横向网格线在边界处的局部曲率两个约束条件来确定，实现了由边界上的网格分布直接控制内部的网格点，使壁面附近具有较密集的网格，并且在整个计算区域内的网格都具有良好的光滑性和正交性，从而保证了流场计算的准确性。

The thickness of aqueous diffusion layer d(subscript a and diffusion coefficient (d0) of Hg through SLM were evaluated by the linear slope method, and they were found to be 1.57×10^(-5) m and 7.26×10^(-13) m^2/s, respectively.

Hg在N503-煤油支撑液膜体系中的扩散层厚度δa为1.57×10^(-5)m，膜内扩散系数d0为7.26×10^(-13)平方公尺/s，确立了Hg的渗透系数P方程。

The reaction-diffusion model was developed to analyze the concentration of enantiomers and the separation factor of the enantioseparation process of chiral emulsion liquid membrane by studying the principle and some factors of mass transfer process. The mass transfer resistance of boundary layer in outer aqueous phase and the interfacial chemical reactions at the liquid membrane interfaces were taken into account in the model equations.

通过对乳状液膜手性分离过程中传质机理的研究以及各影响因素的分析，得到了可以分析和预测乳状液膜手性拆分过程传质的反应-扩散模型，该模型同时考虑了外水相边界层的扩散阻力和手性对映体与载体的反应阻力。

The concentration of D-phenylalanine in the external phase and the separation factorαcan be expressed as: The diffusion of boundary layer in outer aqueous phase is the controlled process while the concentration of D-phenylalanine in the external phase far less than the concentration of chiral carrier in the emulsion liquid membrane phase, then the diffusion coefficient k_e of boundary layer in outer aqueous phase can be achieved by data fitting.

外水相苯丙氨酸对映体的浓度以及分离因子α表示为：当外相对映体浓度远小于液膜相手性载体浓度时，该手性传质过程中外相边界层的扩散为控制步骤，利用数据拟合得到了外水相与液膜相界面边界层扩散的传质系数k_e。

There exist negative correlations between the ionic porosity, which is a measure of atomic packing density in minerals, and Ar and H diffusion activation energies. Thus ionic porosity can be used to predict element diffusion coefficients.

孔隙度作为矿物内部离子堆积密度的一种量度，它与Ar和H的扩散活化能之间存在负的线性相关性，因而可以用于预测元素在矿物中的扩散系数。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。