air impermeability,gas proofness,gas tightness

Effect of impervious surface on stormwater runoff pollution in urban tourist attractions;

城市旅游区暴雨径流污染过程中的不透水面效应

Removal of rural land cover types such as soil,water,and vegetation and their replacement with common urban impervious surface materials such as asphalt,concrete,and metal have significant environmental implications.

城市化的一个重要表现就是不透水面分布比率的上升,城市内部不透水面分布是城市生态环境的一个重要指标。

As a major component of the Ridd s vegetation-impervious surface-soil(V-I-S) model,urban impervious surface is important in monitoring urban expansion and understanding impacts from human activities on the environment.

作为Ridd V-I-S模型中的一个重要组成部分,城市不透水面在监测城市扩展和解释人类活动对生态环境的影响起着非常重要的作用。

Studies of the Experimental Technologies of Radiative Opacity;

辐射不透明度实验技术研究

The calculation of opacity about krypton plasma;

惰性元素氪等离子体不透明度计算

Study on Opacity of Silver Plasma;

银等离子体不透明度研究

Parameters and important factors for determination opacity of plastic pipes and fittings were discussed based on validating and paralleling experiments,according to the international standard ISO/DIS7686 and the change of different revisions.

参照国际标准并结合其不同版本内容的变化 ,通过验证和对比试验 ,对塑料管材与管件不透光性测试的试验参数和操作中的主要影响因素进行了分析 ,对测试方法中的相关问题提出了建