Construction and application of gene targeting replacement vector;
基因打靶置换型载体的构建和应用研究
Based on the principle of gas permeability measurement,this paper analyzes the change in measuring pressure during the measuring process by the rising water and falling water volume displacement methods.
从体积置换法测量木材气体渗透系数的基本原理出发，针对水柱上升和水柱下降两种体积置换法的测量装置，分析了体积置换法测量过程中气体渗透压强的变化，以及非稳态条件对体积置换法测量结果的影响。
According to the current technical level and the concrete situation of the storage/distribution station,this paper puts forward three schemes for the replacement of the natural gas in the spherical tank(inert gas replacement,water replacement and gas direct replacement),and through comparison of these schemes,holds that the gas direct replacement is more convenient and economic.
根据目前的技术水平和储配站的具体情况,提出了3种天然气球罐置换方案(惰性气体置换法、水置换法、燃气直接置换法),经过方案比较,认为天然气直接置换较为方便、经济。