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Showing 2 results for Pilehchian
Volume 10, Issue 1 (Winter 2019)
Abstract
Clostridium perfrinjens is an anaerobics, Gram-positive, rod-shaped and heat resistant bacterium of genus clostridium. C. perfringens is a spore-forming bacterium and widely occurring pathogen. The organism is grouped into 5 types (A, B, C, D, and E) on the basis of the production of 4 major toxins alpha, beta, epsilon, and iota toxins. Tpel Clostridium perfringens (C. perfringens) toxin have identified with A, B, and C types by cytotoxin activity in recent years. In this study C. perfringens type B had been used. Tpel caused to intestinal disease especially intestinal infections in human and necrotic enteritis in birds. In this study, perfect genomic DNA extracted by phenol-chloroform and Polymerase Chain Reaction (PCR) method used to isolation Tpel gene by a couple exclusive primer of perfect bacterium genomic DNA. PCR product after joining to pTZ57RL/T vector by TA cloning method in E. coli strain TOP10 susceptible became cloned and then colony PCR method used to screening transforming bacterium colonies with recombinant plasmid. Presence of fragment close to 2469bp on 1% agarose gel indicated that Tpel gene in E. coli strain TOP10 have be cloned.
Mohammad Reza Pilehchian, Mohammad Hossein Abolbashari,
Volume 17, Issue 5 (7-2017)
Abstract
In this paper, the effect of new control tools on the behavior of the parachute and its performance is studied by applying a compulsive stimulus in flow field. Modeling simulation and analysis performed with Ansys Fluent. A general geometry is proposed and simulations are carried out to indicate the effect of those stimuli on the flow behavior, parachute performance and high pressure areas on parachute. For the simplicity, the assumptions of axisymmetric and rigid wall of the parachute are used. Due to the large range of motion of fins compared to adjacent cells and also the importance of quality of mesh in the vicinity of the solid boundary, spring-based smoothing method for local and area remeshing are employed. In this way, the mesh quality for presenting the boundary layer and vortex generated in the solid surface are enhanced. The results depicted that using spherical arch geometries versus circular sector or parabolic geometries lead to some advantages. Permittivity of disk at the end of the parachute, has been triggered to increase the general drag coefficient dramatically up to around two times larger. Despite the existence of stimulation on a large area, flow field experience a total pressure drop. On the other hand if the stimulus does not exist the area is much smaller.