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61.
Abbas Sharifi Saber Yekani Motlagh Homayoun Badfar 《International Journal of Computational Fluid Dynamics》2013,27(4-5):248-259
ABSTRACTIn this paper, effects of two wires magnetic field on heat transfer and biomagnetic fluid flow in an aneurysm have been investigated using the ferrohydrodynamics model. Using the finite volume method and the SIMPLE algorithm, the governing equations have been discretised. Simulations have been carried out for both conditions of wires in the same and opposite directions and different magnetic numbers of 41 and 82. Results show that the magnetic field causes a decrease in heat transfer of blood flow towards the walls. Moreover, major energy loss or pressure drop, arising from mean wall shear stress, decreases but local or minor energy loss, arising from aneurysm vortexes, increases. Furthermore, risk factors of aneurysm rupture is decreased under the effect of the magnetic field. The effective contact surface between drug-coated magnetic nanoparticles and the aneurysm tissue may increase and residence time of drug on the cells of the region would decrease. 相似文献
62.
Ali Asghar Mohammadi Salman Taheri Arman Amini Reza Ahdenov 《Molecular diversity》2018,22(4):999-1006
Triamide derivatives have been synthesized in good yields in a novel, one-pot, five-component, and efficient process by the reaction of Z-oxazolone, water, primary amines, aldehydes, isocyanides, in the presence of catalytic amount of KAl(SO4)2·12H2O (alum) as a non-toxic, reusable, inexpensive, and easily available reagent via Ugi reaction in aqueous solution. 相似文献
63.
Small angle neutron scattering (SANS) is used to analyze the structure of opals and inverse opals made by the capillary deposition method. We show that there is no deformation in special lattice directions such as the growth direction and the support plane direction. However, effects of twinning of the dense-packed structure and plane-like lattice perturbations have been observed. The latter appear as linear surface disturbances. We propose a model with an anisotropic distribution of stacking faults which delivers the different peak intensities in the neutron diffraction pattern. The rocking curves show that small perfect crystal parts are aligned better than ±3° and ±11° for the opals and inverse opals, respectively. 相似文献
64.
The three-component direct Mannich reaction between aldehydes, p-toluenesulfonamide, and enolizable ketones was achieved for the first time with organic bases as the catalysts. The corresponding N-tosylated β-aminoketones were obtained in high yields and good to excellent diastereoselectivities using TMG as the catalyst. Through reduction of the ketone group, the reaction product may be converted into β-aminol with excellent diastereoselectivity. 相似文献
65.
Ali Sharifi Mehdi Barazandeh M. Saeed Abaee Mojtaba Mirzaei 《Journal of heterocyclic chemistry》2012,49(4):933-938
A medium consisting of K2CO3 and H2O in [omim][BF4] ionic liquid (IL) was used to synthesize N‐substituted 2H‐benzo[b][1,4]oxazin‐3(4H)‐one derivatives from their corresponding o‐aminophenols and 2‐bromoalkanoates. As a result, chemoselective formation of benzoxazinones in high yields has been observed at room temperature. After the reactions and separation of the products, the IL was recovered and successfully reused in subsequent reactions without significant loss of activity. 相似文献
66.
M. Saeed Abaee Mohammad M. Mojtahedi M. Mehdi Zahedi Roholah Sharifi 《Heteroatom Chemistry》2007,18(1):44-49
A remarkable efficient double crossed aldol condensation of heterocyclic ketones with a variety of aromatic aldehydes is described at room temperature in the presence of magnesium bromide ethyl etherate, triethylamine, and methanol under solvent‐free conditions. Excellent yields of 3,5‐bisarylmethylidenes of pyranones and thiopyranones are achieved in a facile one‐pot general procedure. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:44–49, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20252 相似文献
67.
Peloquin Andrew J. Hill Sarah C. Arman Hadi D. McMillen Colin D. Rabinovich Daniel Pennington William T. 《Journal of chemical crystallography》2022,52(1):62-72
Journal of Chemical Crystallography - A new polymorph of N-tert-butyl-2-thioimidazole (1), along with its cocrystals with 1,4-diiodotetrafluorobenzene (2), tetraiodoethylene (3), and molecular... 相似文献
68.
Use of a urea and guanidine-HCl-propanol solvent system to purify a growth inhibitory glycopeptide by high-performance liquid chromatography 总被引:1,自引:0,他引:1
Reversed-phase high-performance liquid chromatography was used to purify an inhibitory glycopeptide where resolution and recovery were enhanced by using urea or guanidine-HCl-isopropanol-water as a solvent system. Isopropanol alone or other solvent systems that have been proposed for such purification steps were not effective in eluting hydrophobic proteins from the reversed-phase column. The application of the urea or guanidine-HCl solvent systems in the separation and purification of membrane proteins, and other hydrophobic macromolecules, could greatly enhance recovery and efficiency of purification. 相似文献
69.
70.
Mehrdad Khatami Iraj Sharifi Marcos A. L. Nobre Niloofar Zafarnia 《Green Chemistry Letters and Reviews》2018,11(2):125-134
Grass waste was used for transform an inexpensive waste into health. Silver nanoparticles (AgNPs) have been synthesized using waste material (dried grass). The average size of silver nanoparticles observed in transmission electron images was estimated to be about 15?nm. The anticancer, antifungal and antibacterial effect of AgNPs were studied in vitro. The minimum inhibitory concentration of AgNPs against Pseudomonas aeruginosa and Acinetobacter baumannii was calculated about 3?µg/ml. The highest level of inhibitory effect of AgNPs against Fusarium solani was close to 90% at a concentration of 20?μg/ml of AgNPs. An inhibitory effect on the cancer cell growth is reach, by increasing the concentration of AgNPs to 5?µg/ml; the cancer cells’ survival decreases about 30%. Western results showed that the expression of Cyclin D1 protein of MCF-7 cell line decreased after treatment with the effective concentration of AgNPs. 相似文献