The oxygen diffusion coefficient in air measured by this method corresponded with data in the literature within 卤6% deviation. The oxygen diffusion coefficients of two kinds of porous media generally used for the GDL were measured by the experimental method for dry and wet samples. The results ...
Oxygen surface exchange and oxygen chemical diffusion coefficients of LaNi0.4Fe0.6O3−δ ceramics are determined via conductivity relaxation method after stepwise change of temperature in the range of 700–950 °C in air and Ar/O2 gas flow at oxygen partial pressures ( \(p_{O_2 } \) )...
Mixed ionic and electronic conductors (MIEC) have presented great economical and environmental interests for these last years because of their potential applications for electrode materials in solid oxide fuel cell and for oxygen separation form air such as in catalytic membrane reactors for methane conv...
1) diffusion coefficient of oxygen 氧气扩散系数 1. The law ondiffusion coefficient of oxygeninfluenced by constructive method . 为了确定施工方法与钢筋位置对混凝土氧气扩散系数的影响规律,应用中国矿业大学耿欧教授的混凝土氧气扩散系数测试装置,在不同温湿度和水灰比的条件下,对钢筋混凝土的上保护层和下保护层...
70,73 The diffusion coefficient is directly dependent upon the solubility of the gas and inversely proportional to the square root of the molecular weight of the gas. With these formulas it can be demonstrated that carbon dioxide has a much higher solubility than oxygen in water (24 : 1...
The volumetric mass transfer coefficients obtained in this column range from 0.067 to 0.1495 s-1 in the range of air superficial velocities from 0.011 to 0.047m/s and vibrational velocities from 0.825 to 6cm/s. Volumetric oxygen mass transfer coefficient has increased with the increase in ...
Oxygen is a colourless gas that exists in large quantities in the air. All plants and animals need oxygen in order to live. e.g. The human brain needs to be without oxygen for only four minutes before permanent damage occurs. 人的大脑缺氧4分钟后便会造成永久性损伤。
diffusion coefficientChapman-Etskog methodairargonnitrogenCalculated values of the viscosity, thermal conductivity and electrical conductivity of air and mixtures of air and argon, air and nitrogen, and air and oxygen at high temperatures are presented. In addition, combined ordinary, pressure, and ...
In this study, 18O2 tracer gas is exchanged with yttrium silicates at temperatures from 1000 – 1300°C and the 18O concentration is quantified and mapped as a function of depth. The objective of this study was to determine the oxygen diffusion coefficient, surface exchange coefficient and activ...
The oxygen transfer in conventional HFCW is poor and inconsistent, which occurs mainly via convection and diffusion from the air to the surface water with estimated oxygen transfer rates of 0.3–3.2 g O2 m−2 d−1 (Kadlec and Wallace, 2009). The conventional VFCW allows oxygen transfer ...