The static capacity method measures nitrogen adsorption differently from the dynamic method. In a closed system, it changes the nitrogen pressure on the surface of the powder sample, gradually changing from 0 to nearly 1 atmosphere, and measuring the sample before and after adsorption with a high-precision pressure sensor. The change in pressure is then calculated based on the gas state equation to calculate the amount of adsorption or desorption of the gas. After measuring the nitrogen adsorption amount, the BET specific surface and pore size distribution can be obtained according to the theoretical formula of nitrogen adsorption. The key factors of static capacity test technology are pressure sensor accuracy, dead volume measurement accuracy, vacuum tightness, sample temperature and coolant level change, and sample chamber temperature field correction. Developed countries such as Europe and the United States basically adopt static capacity nitrogen adsorption instruments. China's annual import volume is also quite large. However, due to its high price, its application in China is limited. In recent years, domestically produced instruments have developed rapidly, and it has become an inevitable trend to replace imports. Stroller Sun Shade,Sun Shade For Stroller,Baby Stroller Sun Shade,Double Stroller Sun Shade DongGuan Baby-Plus baby ware Co., Ltd. , https://www.baby-plus.com
Static volumetric method specific surface area and pore size analyzer test principle and process