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141.
Ashkan Babaie Arman Sadeghi Mohammad Hassan Saidi 《ournal of non Newtonian Fluid Mechanics》2011,166(14-15):792-798
Electroosmotic flow of power-law fluids in the presence of pressure gradient through a slit is analyzed. After numerically solving the Poisson–Boltzmann equation, the momentum equation with electroosmotic body force is solved through an iterative numerical procedure for both favorable and adverse pressure gradients. The results reveal that, in case of pressure assisted flow, shear-thinning fluids reach higher velocity magnitudes compared with shear-thickening fluids, whereas the opposite is true when an adverse pressure gradient is applied. The Poiseuille number is found to be an increasing function of the dimensionless Debye–Hückel parameter, the wall zeta potential, and the flow behavior index. Comparison between the exact and the results based on the Debye–Hückel linearization reveals that the simplified solution leads to large errors in evaluating the velocity profile for zeta potentials higher than 25 mV, except for shear-thickening fluids in the presence of favorable pressure gradient. 相似文献
142.
Tofighi-Niaki Ebrahim Asgharifard-Sharabiani Pouya Ahmadian Hamid 《Nonlinear dynamics》2018,94(4):2937-2956
Nonlinear Dynamics - Rub–impact phenomenon occurring in hydrodynamic journal bearings is one of the main malfunctions in rotating machines and causes undesirable dynamic behavior. In order to... 相似文献
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Mona Sadeghi 《Theoretical and Experimental Chemistry》2010,46(2):132-137
An enzymatic degumming step in the production of edible soybean oil is carried out. The phosphatides are present in free hydratable
form (HP) or in nonhydratable form (NHP). The main characteristic of the discovery is the use of phospholipid A1 (Lecithin
Ultra) enzyme, which catalyzes reactions at specific temperatures. The mechanism includes the conversion of nonhydratable
phospholipids into water-soluble lysophospholipids, which are then removed by centrifuge, yielding degumming oil low in phosphorus.
The effects of important determining factors affecting oil degumming such as enzyme dosage, temperature and pH are investigated. 相似文献
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A new, mild, and novel method is described for the efficient deoxygenation of sulfoxides to their corresponding sulfides with 1,3-dithiane at room temperature in the presence of catalytic amounts of N-bromosuccinimide (NBS), 2,4,4,6-tetrabromo-2,5-cyclohexadienone (TABCO), or Br(2) as the source of electrophilic bromine. 相似文献
150.
Simultaneous microwave and ultrasound irradiation is shown as a new technique for digestion of solid and liquid samples suitable for chemical and food analysis. Its application in analytical chemistry has been shown by decreases in digestion time: determination of copper in edible oils and total Kjeldahl nitrogen. 相似文献