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91.
High density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP) and poly(vinyl chloride) (PVC) with Phragmiteskarka wood flour (WF) and polyethylene-co-glycidyl methacrylate (PE-co-GMA) was used to develop wood polymer composite (WPC) by solution blending method. The effect of addition of nanoclay and TiO2 on the properties of the composite was examined. The exfoliation of silicate layers and dispersion of TiO2 nanopowder was studied by X-ray diffractometry and transmission electron microscopy. The improvement in miscibility among polymers due to addition of compatibilizer was studied by scanning electron microscopy (SEM). WPC treated with 3 phr each of clay and TiO2 showed an improvement in thermal stability. Mechanical, UV resistance and flame retarding properties were also enhanced after the incorporation of clay/TiO2 nanopowder to the composites. Both water and water vapor absorption were found to decrease due to inclusion of nanoclay and TiO2 in WPC. 相似文献
92.
Fermentation optimization for a probiotic local northeastern Indian rice beer and application to local cassava and plantain beer production 下载免费PDF全文
Arup Jyoti Das Dibyakanta Seth Tatsuro Miyaji Sankar Chandra Deka 《Journal of the Institute of Brewing》2015,121(2):273-282
Response surface methodology was employed to determine the optimal conditions of time and temperature for the fermentation of a local North East Indian rice beer. The same conditions were then applied to prepare local beers from cassava (Manihot esculanta) and plantain (Musa ABB). Saccharomyces cerevisiae, Aspergillus oryzae and Lactobacillus plantarum were used to carry out the fermentation process. Thirteen experimental runs, based on a two‐factor five‐level design were carried out according to a central composite rotatable design. The independent variables were fermentation time (24–216 h) and temperature (25–40°C). The responses studied were content of protein, alcohol, total polyphenols, reducing sugars as well as titratable acidity and L. plantarum count. Numerical optimization predicted that a fermentation period of 143 h at a temperature of 33°C would result in a desirable rice beer, with response values of protein content OF 0.77%, alcohol content OF 6.99%, L. plantarum count of 7.08 log CFU mL?1, polyphenol content of 34.46 mg/100 g, reducing sugars of 2.39% and a titratable acidity of 0.34%. Cassava and plantain beers were prepared using the optimized parameters of the rice beer experiments and the resultant beers exhibited the desired chemical parameters, suggesting applicability of the conditions to preparing these types of local beers from a wider range of substrates. Copyright © 2015 The Institute of Brewing & Distilling 相似文献
93.
Wood polymer nanocomposite (WPC) was prepared by solution blending of high density polyethylene, low density polyethylene,
polypropylene and polyvinyl chloride (1:1:1:0.5) with wood flour and nanoclay. Xylene and tetrahydrofuran were used as solvent
and the ratio was optimized at 70:30. TEM study revealed better dispersion of silicate layers in WPC loaded with 3 wt% of
clay. WPC loaded with 3 wt% nanoclay exhibited higher thermal stability compared to WPC loaded with 1 and 5 wt% clay. The
storage and loss modulus were found to enhance on incorporation of clay to WPC. The damping peak was found to be lowered by
the addition of clay to WPC. Limiting oxygen index value increased due to incorporation of nanoclay. WPCs were subjected to
exposure to cellulase producing Bacillus sp. and it showed the growth of bacteria as revealed by SEM study. Mechanical properties of WPC decreased due to degradation
by bacteria. Water vapour uptake of WPC decreased due to addition of nanoclay. 相似文献
94.
Kunal B. Modi Pooja Y. Raval Dolly J. Parekh Shrey K. Modi Niketa P. Joshi Akshay R. Makadiya Nimish H. Vasoya Utpal S. Joshi 《半导体学报》2022,43(3):032001-032001-10
The electrical properties of cubic perovskite series, CaCu3–xTi4–xFe2xO12 with x = 0.0, 0.1, 0.3, 0.5, and 0.7, have been studied by employing current density as a function of electric field characteristics registered at different temperatures and thermal variations of direct current electrical resistivity measurements. All of the compositions exhibit strong non-ohmic behavior. The concentration dependence of breakdown field, the temperature at which switching action takes place, and maximum value of current density (Jmax) has been explained on account of structural, microstructural, and positron lifetime parameters. The highest ever reported value of Jmax = 327 mA/cm2 has been observed for pristine composition. The values of the nonlinear coefficient advise the suitability of ceramics for low-voltage varistor applications. The Arrhenius plots show typical semiconducting nature. The activation energy values indicate that electric conduction proceeds through electrons with deformation in the system. 相似文献
95.
A linear stability analysis has been presented for the flow between long concentric stationary porous cylinders driven by constant azimuthal pressure gradient, when a radial flow through the permeable walls of the cylinders is present. The radial Reynolds number, based on the radial velocity at the inner cylinder and the inner radius is varied from −100 to 30. The linearized stability equations form an eigenvalue problem which are solved using a numerical technique based on classical Runge-Kutta scheme combined with a shooting method, termed as unit disturbance method. It is observed that radially outward flow and strong inward flow have a stabilizing effect, while weak inward flow has a destabilizing effect on the stability. Profiles of the relative amplitude of the perturbed radial velocities show that radially outward flow shifts the vortices toward the outer cylinder, while radially inward flow shifts the vortices toward the inner cylinder. 相似文献
96.
Experimental observation of simultaneous oscillation at the Raman frequency and a cascade frequency in a broadly tunable13CH3 F far-infrared laser is reported. Oscillation on both components persists over the full 25 GHz separation between thev_{3}R(36) andR(37) lines. This observation is in marked contrast to the behavior of the tunable12CH3 F FIR laser which produces only the Raman frequency when it is optically pumped at lowerJ values in the same branch. A marked qualitative difference in the large-scale emission spectra for the two lasers is also discussed. 相似文献
97.
Thermal stress in annular fins, which influences the life of a fin, still needs its detail analysis. Heat transfer in annular fins is studied here as a multiobjective optimization problem. Representing fin profiles by B-spline curves, fin geometries are obtained primarily by maximizing heat transfer rate and minimizing thermal stress. Fin performance is further assessed by minimizing fin volume and maximizing fin efficiency and effectiveness. Evaluating temperature and thermal stress by hybrid spline difference method, non-dominated sorting genetic algorithm II is applied to approximate the Pareto-optimal front. The proposed procedure would be helpful for designers to adopt suitable fin configurations from the Pareto front. 相似文献
98.
Duyi Samyor Amit Baran Das Sankar Chandra Deka 《International Journal of Food Science & Technology》2017,52(5):1073-1081
Rice (Oryza sativa L.) is one of the most important food crops in the world. In red rice, black, purple, brown, and brown red rice, major bioactive components are gallic, protocatechuic, hydroxybenzoic, p‐coumaric,ferulic, sinapic acid, cyanidin‐3‐O‐glucoside, peonidin‐3‐O‐glucoside,flavan‐3‐ol (+) catechin and (?) epicatechin,flavanols (flavan‐ 3‐ols), isoflavones, γ‐oryzanol contents, compositions of steryl, triterpene alcohol ferulates proportions, and tocopherols, etc. This review provides information of pigmented rice in the form of bioactive compounds, concentration, activities and its health's benefit. These bioactive compounds are having immense potential for many health benefit effects and can act as antitumour, anti‐atherosclerosis, anti‐diabetic, anti‐allergicagents, alleviating gallstones, anticancer activity, anti‐inflammatoryeffects, and others. 相似文献
99.
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