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101.
Polymer composite comprising polyvinylidene fluoride (PVDF) and potassium hexatitante (K2Ti6O13) was synthesized by solution casting. The effect of K2Ti6O13 on surface, thermal, and electrical properties of polymer composite were investigated. The addition of K2Ti6O13 with polymer leads to thermal degradation and transition of polymer composite from semi-crystalline to amorphous phase. The optimum results of contact angle for different loading wt% of K2Ti6O13 were directly correlated with the surface morphology. Our experimental results confirmed the incorporation of K2Ti6O13 in polymer by SEM micrographs. The evaluated dielectric properties (ε' = 424; tan δ = 2.14 at 130 °C and 100 Hz frequency for 20 wt% loading of K2Ti6O13) for polymer composite are higher in compared to pure polymer. The enhancement in dielectric constant and changing the surface properties of polymer composite can be used for the development of electrochemical storage device applications. 相似文献
102.
Vanadium redox flow battery (VRFB) is a promising technology for large-scale renewable energy storage. Design of ion-exchange membrane (IEM) with desired properties like low-cost, mechanically chemically stable, low vanadium ion permeability and high proton conductivity is one of the major challenges. Here, we report the design and synthesis of novel poly(tetrafluoroethylene)-zirconium phosphate (PTFE-ZrP) asymmetric IEM using a simple brush coating method. XRD results confirmed the presence of α-ZrP crystalline phase onto the top layer of the membrane. Excellent mechanical strength was observed with burst pressure of 3.22 × 105 N m?2. Oxidative stability of membrane in Fenton’s reagent was much better than Nafion-115. Vanadium ion (V4+) permeability of the membrane was more than three times lower than that of Nafion-115. Single-cell VRFB with PTFE-ZrP membrane showed ~80% energy efficiency below 30 mA cm?2. Very high columbic efficiency ~100% of VRFB with PTFE-ZrP membrane confirmed little contamination of electrolyte due to cross-mixing. 相似文献
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Sabu A Sarita S Pandey A Bogar B Szakacs G Soccol CR 《Applied biochemistry and biotechnology》2002,102(1-6):251-260
Solid-state fermentation of coconut oil cake has been carried out with Rhizopus oligosporus for the production of phytase. Phytase is used commercially in the animal feed industry to improve animal performance because
there is a substantial and growing interest among swine and poultry producers in the application of phytase to improve the
nutritional quality in animal feeds. Demonstrated benefits include improved feed yield ratios and reduction in the environmental
costs associated with the disposal of animal wastes. We report the production of extracellular phytase by R. oligosporus under solid-state fermentation using coconut oil cake as substrate. Maximal enzyme production (14.29 U/g of dry substrate)
occurred at pH 5.3, 30°C, and 54.5% moisture content after 96 h of incubation. The addition of extra nutrients to the substrate
resulted in inhibition of product formation. The results indicate the scope for production of phytase using coconut oil cake
as solid substrate without additional nutrients. 相似文献
106.
Kozyrev AN Zheng G Shibata M Alderfer JL Dougherty TJ Pandey RK 《Organic letters》1999,1(8):1193-1196
[formula: see text] A novel approach for the preparation of symmetrical (chlorin-chlorin), and unsymmetrical (chlorin-porphyrin) dimers joined with carbon-carbon linkages as models to study the "intramolecular" charge transfer is discussed. 相似文献
107.
J.C. Joshi N.C. Pandey B.C. Joshi B.C. Pandey J. Joshi 《Solid State Communications》1978,27(11):1051-1053
Characteristic visible green emission of Ho3+ and Er3+ was observed in zinc tellurite glass. Multiphonon relaxation theory was quantitatively applied to explain the experimentally obtained results. Fluorescence assignments and lifetime measurements have also been made. 相似文献
108.
The two-point correlation function for complex spectra described by the Gaussian Orthogonal Ensemble (GOE) is calculated, and its essential simplicity displayed, by an elementary procedure which derives from orthogonal invariance and the dominance of intrinsic binary correlations. The resultant function is used for an approximate calculation of the standard fluctuation measures. Good agreements are found with exact results where these are available, this incidentally demonstrating that the measures are, for the most part, two-point measures. It is shown that they vary slowly over the spectrum, a result which is in agreement both with experiment and with Monte Carlo calculations. The same technique can be used for higher-order correlation functions, and possibly also for more complicated ensembles in which case the results would be relevant to the question why GOE fluctuations give a good account of experimental results. 相似文献
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The motion of test particles in the field of a plane gravitational wave is studied in order to derive some general properties of such motion, especially the possibilities of repeated meetings of two inertially moving particles.The work was done at Moscow State University, Moscow. 相似文献