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101.
102.
In the present communication we report normal modes and their dispersion in polydimethylsilane (PDMS) [-Si(CH3)2-]n using Urey-Bradley force field, which in addition to valence force field accounts for the non-bonded interactions in the gem and cis configurations and tension terms. The partially deuterated PDMS (PDMS-d3), i.e., (SiCH3CD3)n and fully deuterated PDMS (PDMS-d6), i.e., (SiCD3CD3)n are also studied to check the assignments and validity of the force field. Dispersion curves show two interesting features: (1) a divergence of dispersion curves following repulsion of species belonging to the same symmetry; (2) crossing between the two modes. In addition, heat capacity as a function of temperature via density-of-states is evaluated and some of the modes left unassigned by the earlier workers have been assigned. 相似文献
103.
Gluconic acid was obtained in the permeate side of the bioreactor with glucose oxidase (GOD) immobilized onto anion-exchange membrane (AEM) of low-density polyethylene grafted with 4-vinylpiridine. The electric resistance of the anion-exchange membranes was increased after the enzyme immobilization on the membrane. The gluconic acid productions were relatively low with the GOD immobilized by any method on the AEM. To increase the enzyme reaction efficiency, GOD was immobilized on membrane of AN copolymer (PAN) adjacent to an anion-exchange membrane in bioreactor. Uses of anion-exchange membrane led to selective removal of the gluconic acid from the glucose solution and reduce the gluconic acid inhibition. The amount of gluconic acid obtained in the permeate side of the bioreactor with the GOD immobilized on the PAN membrane adjacent to the AEM under electrodialysis was about 30 times higher than that obtained with enzyme directly bound to the AEM. The optimal substrate concentration in the feed side was found to be about 1 g/l. Further experiments were carried out with the co-immobilized GOD plus Catalase (CAT) on the PAN membrane adjacent to the AEM to improve the efficiency of the immobilize system. The yield of this process was at least 95%. The storage stability of the co-immobilized GOD and CAT was studied (lost 20% of initial activity for 90 d). The results obtained clearly showed the higher potential of the dual membrane bioreactor with GOD plus CAT bound to ultrafiltration polymer membrane adjacent to the AEM. Storage stability of GOD activity in GOD plus CAT immobilized on PAN//AEM membranes and on AEM. 相似文献
104.
Mathiazhakan Kuttiraja Ayed Douha Jose R. Valéro Rajeswar Dayal Tyagi 《Applied biochemistry and biotechnology》2016,178(8):1586-1598
The high demand for renewable energy and increased biodiesel production lead to the surplus availability of crude glycerol. Due to the above reason, the bio-based value addition of crude glycerol into various bioproducts is investigated; among them, microbial lipids are attractive. The present study was dedicated to find the optimal glycerol concentration and carbon/nitrogen (C/N) ratio to produce maximum lipid using Yarrowia lipolytica SKY7. The glycerol concentration (34.4 to168.2 g/L) and C/N ratio (25 to 150) were selected to investigate to maximize the lipid production. Initial glycerol concentration 112.5 g/L, C/N molar ratio of 100, and with 5 % v/v inoculum supplementation were found to be optimum for biomass and lipid production. Based on the above optimal parameters, lipid concentration of 43.8 % w/w with a biomass concentration of 14.8 g/L was achieved. In the case of glycerol concentration, the maximum Yp/s (0.192 g/g); Yx/s (0.43 g/g) was noted when the initial glycerol concentration was 112.5 g/L with C/N molar ratio 100 and inoculum volume 5 % v/v. The glycerol uptake was also noted to increase with the increase in glycerol concentration. At low C/N ratio, the glycerol consumption was found to be high (79.43 g/L on C/N 25) whereas the glycerol consumption was observed to decrease when the C/N ratio was raised to 150 (40.8 g/L). 相似文献
105.
We have synthesized nanosized La0.67Ca0.33MnO3 by a simple low-cost novel synthesis route without calcination at high temperature. The study of these nanoparticles indicates
excellent properties similar to colossal magnetoresistance (CMR) materials sintered at ∼1600°C for 20 h. The resulting particle
size is in the range of 50–160 nm as determined by scanning electron microscopy. Resistivity measurement has been carried
out down to 12 K. The sample shows metal-to-insulator (M–I) transition at 205 K.
相似文献
106.
Saran Dayal Sagar Rohan Gaur Mulayam Singh 《Journal of Thermal Analysis and Calorimetry》2019,136(4):1679-1686
Journal of Thermal Analysis and Calorimetry - The aim of the present work is to study the effect of magnetic field on thermally stimulated discharge current (TSDC) characteristics and dielectric... 相似文献
107.
Mathiazhakan Kuttiraja Ayed Dhouha Rajeshwar Dayal Tyagi 《Applied biochemistry and biotechnology》2018,184(4):1332-1346
The objective of this research was to investigate the kinetics of lipid production by Yarrowia lipolytica SKY7 in the crude glycerol-supplemented media with and without the control of pH. Lipid and citric acid production were improved with the pH control condition. There was no significant difference observed in the biomass concentration with or without the pH control. In the pH-controlled experiments, the biomass and lipid concentration reached 18 and 7.78 g/L, (45.5% w/w), respectively, with lipid yield (Yp/s) of 0.179 g/g at 60 h of fermentation. The lipid production was directly correlated with growth and the process was defined as growth associated. After 60 h of fermentation, the lipid degradation was noticed in the pH-controlled reactor whereas it occurred after 84 h in the pH-uncontrolled reactor. Apart from lipid, citric acid was produced as the major extracellular product in both fermentations but the much lower concentration in uncontrolled pH. Based on the experimental results, it is evident that controlling the pH will enhance the lipid production by 15% compared to pH-uncontrolled fermentation. 相似文献
108.
109.
A real-time holographic interferometry technique is suggested for recording the isopachic patterns corresponding to transparent anisotropic composites. The isochromatic and isopachic patterns are obtained for a transparent glass-epoxy composite disk with a central hole subjected to diametral compression. A method is suggested for interpreting the optical data and to obtain the separate values of stress components. Its application is demonstrated. 相似文献
110.