in this work, the characteristics of flow and heat transfer of a fluid containing nano particles of aluminum oxide with the water volume fraction (0.1-0.2-0.3)(v/v) percent of the reports. the overall heat transfer coefficient, heat transfer and the average heat transfer fluid containing nano water - aluminum oxide in a horizontal double pipe counter flow heat exchanger under turbulent flow con...

in this paper, nonlinear vibration and instability response of an embedded pipe conveying viscose fluid is investigated. the pipe is considered as a timoshenko beam embedded on an elastic foundation which is simulated by spring constant of the winkler-model and the shear constant of the pasternak-model. the external flow force, acting on the beam in the direction of the flexural displacement is...

effects of some thermo-physical parameters on free convective heat and mass transfer over a vertical stretching surface at lowest level of heat energy in the presence of suction is investigated. the viscosity of the fluid is assumed to vary as a linear function of temperature and thermal conductivity is assumed constant. a similarity transformation is applied to reduce the governing equations i...

statement of problem: changes in protein levels, host calls enzymes and inflammatory mediators in gingival crevicular fluid (gcf) are considered as diagnostic indicators of periodontitis.purpose: he aim of the present study was to measure the elastase enzyme activity in gingival crevicular fluid among patients with periodontitis.material and methods: in this study, 52 periodontitis patients (ex...

in this study, a computational fluid dynamics (cfd) model was developed to evaluate ultraviolet disinfection applesauce reactor. to simulate uv reactors, three sets of equations, including hydrodynamics, radiation and species mass conservation were solved simultaneously. the realizable k-e turbulence model and the discrete ordinate method were used to find the uv radiation profile through the r...

increasing the thermal stability and resistance to bacterial attack (bioresistance) of the potato starch used in the water-based drilling fluid is the aim of this work. four types of potato starch grafted with acrylamide and a mixture of each one with acrylic acid, 2-acrylamido-2-methyl-1-propane sulfuric acid and itaconic acid were synthesized by manganese (iv)-induced redox system at the suit...

a pressurized fluid extraction (pfe) method for the extraction of pistachio oil was developed using a modified supercritical fluid extractor. the supercritical fluid extraction apparatus was modified to be able to pump liquid solvent and co2 into the extraction vessel alternatively. the experimental results showed that the extraction yield was independent of the extraction pressure. it was also...

treatment of hydrocephalus in posterior fossa tumors in children is still a matter of controversy and different centers have their own routines. in this regard, hospital records of all children with posterior fossa tumors treated in our center during the interval of 1985-1995 were reviewed. patients’ demographic and diagnostic data were analyzed and the frequencies of shunting procedures were d...

mumps infection is endemic in iran. our objective was to evaluate the presence of anti mumps antibodies ( igm & igg) in cerebrospinal fluid in mumps meningoencephalitic children. a prospective/cross-sectional study was performed in tehran, iran (2003 to 2004) and serum anti mumps antibodies (igm) were detected (quantitive; elisa) in meningoencephaltis patients. specific anti mumps antibodies (i...