3D modeling of Pd/α-Al2O3 hollow fiber membrane by using computational fluid dynamic for hydrogen separation from H2/N2 mixture was considered in steady and unsteady states by using the concept of characteristic time. Characteristic time concept could help us to design and calculate surface to volume ratio and membrane thickness, and adjust the feed conditions. The contribution of resistance be...

thin film phthalocyanines(pc), incloding zinc, iron, and magnesium phthalocyani-nes, were prepared by vacuum deposition method. chronocoulometry was used to study the charge transfer reaction mechanism of ionic species through the thin films. the results obtained in chronocoulometric studies shows that the thin film phthalocyanines could operate via two mechanisms.the first mechanism metal pc t...

Introduction: In implantation, endometrial epithelium is affected by the release of steroid hormones secreted from the ovary and allows the blastocyst to bind. This course is called the “implantation window” and occurs about 4-10 days after the onset of progesterone secretion. Therefore, the endometrium undergoes changes in the configuration of microvilli in the apical membrane, as well as the ...

output characteristics of fuel cells are affected by a large number of parameters such as geometry, dimensions, construction materials and conditions of supplying fluids. in this paper a mathematical model followed by a two-dimensional numerical approach has been presented to study the fuel cell parametrically. effect of oxygen concentration at gas diffusion layer entrance, temperature and pres...

Output characteristics of fuel cells are affected by a large number of parameters such as geometry, dimensions, construction materials and conditions of supplying fluids. In this paper a mathematical model followed by a two-dimensional numerical approach has been presented to study the fuel cell parametrically. Effect of oxygen concentration at gas diffusion layer entrance, temperature and ...

The performance of an optimized tree-type cylindrical-shaped nanoporous fltering membrane proposed in the former study is analytically investigated for varying operational parameter values. Across the membrane thickness, this membrane has two-leveled tree-structured pores including one trunk pore and the multiple branch pores. The physical properties of the surfaces of ...

statement of problem: there are limited histomorphometric studies on biologic efficacy of high density tetrafluoroethylen (d-ptfe) membrane. objectives: to investigate the healing of surgically induced grade ii furcation defects in dogs following the use of dense polytetrafluoroethylene as the barrier membrane and to compare the results with the contra lateral control teeth without the applicat...

The 70SiO2-15TiO2-15ZrO2 membrane was prepared by a sol-gel procedure. The corrosion behavior of microporous toplayers along with the membrane characterization in terms of pore size, surface area, pore volume and weight loss is described. The final ceramic membrane with a thickness of 400 nm and uniform surface was obtained. This membrane confirmed the fine microporous characteristic with mean ...