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排序方式: 共有196条查询结果,搜索用时 272 毫秒
31.
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
32.
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
33.
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
34.
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
35.
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
36.
The amount of corn stover and wheat straw that can be sustainably collected in North Carolina was estimated to be 0.64 and
0.16 million dry t/yr, respectively. More than 80% of these crop residues are located in the coastal area. The bioethanol
potential from corn stover and wheat straw was estimated to be about 238 million L (63 million gal/yr) in North Carolina.
The future location of ethanol plant in North Carolina was estimated based on feedstock demand and collection radius. It is
possible to have four ethanol plants with feedstock demand of 400, 450, 500, and 640 dry t/d. The collection radii for these
four ethanol plants are 46, 60, 42, and 67 km (28, 37, 26, and 42 miles), respectively. The best location for a bioethanol
plant includes four counties (Beaufort, Hyde, Tyrrell, and Washington) with feedstock demand of 500 t/d and collection radius
about 26 mile. 相似文献
37.
Farzaneh Tajfirooz Abolghasem Davoodnia Mehdi Pordel Mahmoud Ebrahimi Amir Khojastehnezhad 《应用有机金属化学》2018,32(1)
New functionalized magnetic core–shell nanoparticles, CuFe2O4@SiO2‐OP2O5H, were prepared by grafting of phosphorus pentoxide on CuFe2O4@SiO2 nanoparticles and characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, energy‐dispersive X‐ray analysis, inductively coupled plasma optical emission spectrometry and vibrating sample magnetometry. The catalytic activity of CuFe2O4@SiO2‐OP2O5H as a novel catalyst was evaluated in the synthesis of 1,8‐dioxo‐octahydroxanthenes under solvent‐free conditions. The results showed that the catalyst has high activity and the desired products are obtained in high yields within short reaction times. The catalyst is readily recovered using magnetic decantation and can be used at least four times without noticeable deterioration in catalytic activity. 相似文献
38.
39.
Marziyeh Rohaniyan Abolghasem Davoodnia S. Ali Beyramabadi Amir Khojastehnezhad 《应用有机金属化学》2019,33(5)
New Schiff base (SB) functionalized graphene oxide (GO) nanosheets containing phosphomolybdic counter‐anion H2PMo12O40¯ (H2PMo) were successfully prepared by grafting of 3‐aminopropyltriethoxysilane (APTS) on GO nanosheets followed by condensation with benzil and finally reaction with phosphomolybdic acid (H3PMo12O40, denoted as H3PMo) and characterized using Fourier transform infrared (FT‐IR) spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), particle size distribution, energy‐dispersive X‐ray (EDX) analysis, EDX elemental mapping, and inductively coupled plasma optical emission spectrometry (ICP‐OES). The prepared new nanomaterial, denoted as GO‐SB‐H2PMo, was shown to be an efficient heterogeneous catalyst in one‐pot, three‐component reaction of β‐naphthol, aldehydes, and dimedone, giving high yields of tetrahydrobenzo[a]xanthene‐11‐ones within short reaction times. The catalyst is readily recovered by simple filtration and can be recycled and reused several times with no significant loss of catalytic activity. 相似文献
40.