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排序方式: 共有426条查询结果,搜索用时 287 毫秒
81.
A.N. Behkami M. Gholami M. Kildir M. Soltani 《理论物理通讯》2006,46(3):514-520
The statistical properties of interacting fermions have been studied for various angular momentum with the inclusion of pairing interaction. The dependence of the critical temperature on angular momentum for several nuclei, have been studied. The yrast energy as a function of angular momentum for 28Si and 24 Mg nuclei have been calculated up to 60.0 MeV of excitation energy. The computed limiting angular momenta are compared with the experimental results for ^26Al produced by ^12C+ 14N reaction. The relevant nuclear level densities for non-zero angular momentum have been computed for ^44Ti and ^136 Ba nuclei. The results are compared with their corresponding values obtained from the approximate formulas. 相似文献
82.
Experimental measurements were carried out on the boiling heat transfer characteristics of γ-Al2O3/water and SnO2/water Newtonian nanofluids. Nanofluids are liquid suspensions containing nanoparticles with sizes smaller than 100 nm. In
this research, suspensions with different concentrations of γ-Al2O3 and SnO2 nanoparticles in water were studied under nucleate pool boiling heat transfer conditions. Results show that nanofluids possess
noticeably higher boiling heat transfer coefficients than the base fluid. The boiling heat transfer coefficients depend on
the type and concentration of nanoparticles. 相似文献
83.
Safa Raziyeh Soltani Goharrizi Ataallah Jafari Saeed Jahanshahi Javaran Ebrahim 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2497-2514
Journal of Thermal Analysis and Calorimetry - In the present study, double-diffusive mixed convection related to the heat and mass transfer of the solid particles dissolution in a shear flow was... 相似文献
84.
Masoud Homayouni-Tabrizi Ehsan Karimi Farideh Namvar Mozhgan Soltani Vahid Pouresmaeil 《Research on Chemical Intermediates》2018,44(11):6537-6548
The aim of the present study is to evaluate the antioxidant and proapoptotic effects of silver–palm pollen (Ag/PP) nanocomposite. The percentage of live cells after treatment with various concentrations of Ag/PP (0, 5, 10, 20, and 40 µM/mL) was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. The antioxidant potential of Ag/PP was measured via the scavenging effects of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and molecular analysis. Apoptosis was assessed by morphological analysis, fluorescent dye, and flow cytometry, and its fundamental mechanism studied based on evaluation of Bax and Bcl2 gene expression. Ag/PP nanocomposite suppressed the viability of MCF-7 cells (dose and time dependently) and showed antioxidant properties. Morphological changes associated with cell death were observed in treated cells. Accumulation of dead cells in sub-G1 phase confirmed the occurrence of apoptosis in exposed cells. In addition, NPs induced cell death by altering Bcl-2 expression in MCF-7 cells. These results indicate that Ag/PP nanocomposite is an effective combination for removal of cancer cells by induction of apoptosis and could be useful for human health due to its antioxidant effects. 相似文献
85.
Behruz Feriduni Mir Ali Farajzadeh Mohammad Barzegar Shahram Sadeghvand Maryam Khoubnasabjafari Abolghasem Jouyban 《Journal of the Iranian Chemical Society》2018,15(11):2503-2510
A simple, sensitive, and rapid analytical method has been developed and validated for the extraction and quantification of valproic acid and its main metabolite (3-heptanone) in human plasma. Initially, the proteins of plasma were precipitated with trifluoroacetic acid. Then a very small volume of a water-immiscible extractant and acetonitrile was mixed and rapidly injected into the pre-treated plasma sample. For further turbidity (dispersion of the extractant into sample solution), the cloudy solution was vortexed. After centrifugation, the settled phase was injected into gas chromatography-flame ionization detection. The effective parameters, such as type and volume of extraction and disperser solvents, vortex time, and pH were studied and optimized. The limits of detection of valproic acid and 3-heptanone were obtained, 0.065 and 0.015 mg L?1, respectively. An acceptable precision was obtained for a concentration of 2 mg L?1 of each analyte (relative standard deviation?≤?8%). The average absolute recoveries (n?=?3) of valproic acid and 3-heptanone were 52?±?2 and 42?±?1%, respectively. The validated method has been successfully used in analysis of the analytes in human plasma samples. 相似文献
86.
Applicability of a solution model, i.e. Jouyban-Acree model (JAM), for calculating surface tension of binary and ternary solvents at various temperatures has been shown employing experimental surface tension data collected from the literature. The accuracy of the model was evaluated by calculating average percentage deviation (APD) between calculated and observed values. The obtained overall APD (+/-S.D.) for JAM using binary solvent data were 4.06 (+/-4.27) and 8.07 (+/-9.78)%, respectively for correlative and predictive analyses. The corresponding values for the best similar model from the literature were 8.86 (+/-6.40) and 37.10 (+/-27.65)% and the mean APD differences between JAM and previously published model were significant (p<0.003). The capability of JAM for correlating surface tension of ternary solvents at various temperatures was also shown and the overall APD was 1.39 (+/-0.37)%. 相似文献
87.
Applicability of a solution model for calculating salt's solubility in binary solvent mixtures was shown. The accuracy of the proposed model was evaluated by computing mean percentage deviation (MPD) employing available solubility data of electrolytes in binary solvents at various temperatures from the literature. The overall MPD (+/-S.D.) for correlation of solubility data was 4.7+/-5.1% and for prediction using model trained by a minimum number of experimental data points was 10.5+/-12.5%. 相似文献
88.
Abolghasem Shahbazi Michele R. Mims Yebo Li Vestal Shirley Salam A. Ibrahim Antrison Morris 《Applied biochemistry and biotechnology》2005,122(1-3):529-540
The performance of immobilized Bifidobacterium longum in sodium alginate beads and on a spiral-sheet bioreactor for the production of lactic acid from cheese whey was evaluated.
Lactose utilization and lactic acid yield of B. longum were compared with those of Lactobacillus helveticus. B. longum immobilized in sodium alginate beads showed better performance in lactose utilization and lactic acid yield than L. helveticus. In the spiral-sheet bioreactor, a lactose conversion ratio of 79% and lactic acid yield of 0.84 g of lactic acid/g of lactose
utilized were obtained during the first run with the immobilized L. helveticus. A lactose conversion ratio of 69% and lactic acid yield of 0.51 g of lactic acid/g of lactose utilized were obtained during
the first run with immobilized B. longum in the spiral-sheet bioreactor. In producing lactic acid L. helveticus performed better when using the Spiral Sheet Bioreactor and B. longum showed better performance with gel bead immobilization. Because B. longum is a very promising new bacterium for lactic acid production from cheese whey, its optimum fermentation conditions such as
pH and metabolic pathway need to be studied further. The ultrafiltration tests have shown that 94% of the cell and cheese
whey proteins were retained by membranes with a mol wt cutoff of 5 and 20 KDa. 相似文献
89.
Ahmad Rouhollahi Mohammad Reza Ganjali Abolghasem Moghimi Gerald W. Buchanan Mojtaba Shamsipur 《Journal of inclusion phenomena and macrocyclic chemistry》1999,33(4):361-376
A synthetic procedure has been developed for the preparation of 4-carboxy-benzo-30-crown-10. The formation of Na+, K+, Rb+, Cs+ and Tl+ complexes with the large crown ether was investigated conductometrically in acetonitrile solution at various temperatures. The formation constants of the resulting 1:1 complexes were determined from the molar conductance-mole ratio data. It was found that the stability of the complexes vary in the order Tl+ > K+ > Rb+ > Cs+ > Na+. The data obtained in this study support the existence of a wrap around structure for the above complexes in solution. The enthalpy and entropy of complexation reactions were determined from the temperature dependence of the formation constants. In all cases, the complexes were enthalpy stabilized but entropy destabilized. The resulting TS° vs. H°plot showed a fairly good linear correlation, indicating the existence of an entropy-enthalpy compensation in the large crown complexation reactions. 相似文献
90.
Applicability of a previously published equation for calculating the solubility of solutes in supercritical carbon dioxide was extended to calculate the solubility in entrained supercritical carbon dioxide employing 42 experimental data sets collected from the literature. The accuracy of the proposed model was evaluated by calculating both the average absolute relative deviation and the individual absolute relative deviation. The proposed model showed superiority to a previously published similar model, from both correlation and prediction points of view. 相似文献