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21.
To enhance the binding and quality of enrobed buffalo meat cutlets (EBMC), a meat emulsion at 0%, 15%, 20% and 25% replaced the cooked meat in the formulation. Emulsion containing products had significantly higher moisture contents and texture scores compared to the control. Emulsion at 20% level could be incorporated in enrobed buffalo meat cutlets to enhance their quality. Addition of 1% egg white powder improved the quality of EBMC compared to control, while a 3% level had adverse effect on the sensory attributes despite giving higher product yield and lower shrinkage. Cutlets with refined wheat flour had significantly higher protein and fat contents. It had also higher acceptability followed by corn flour, potato starch and tapioca flour. TBARS of enrobed samples remained lower than controls throughout the storage period. Mesophilic count remained below log3cfu/g for both samples during storage. Uncoated products and enrobed products were acceptable up to 10th and 15th day, respectively. Enrobing of buffalo meat cutlets improved their acceptability and shelf life under refrigeration storage.  相似文献   
22.
In the present study, the heat transfer performance and friction factor characteristics in a circular tube fitted with twisted wire brush inserts were investigated experimentally. The twisted wire brush inserts were fabricated with four different twisted wire densities of 100, 150, 200, and 250 wires per centimeter by winding a 1 mm diameter of the copper wire over a 5 mm diameter of two twisted iron core-rods. Heat transfer and friction factor data in tubes were examined for Reynolds number ranging from 7,200 to 50,200. The results indicated that the presence of twisted wire brush inserts led to a large effect on the enhancement of heat transfer with corresponding increase in friction factor over the plain tube. The Nusselt number and friction factor of using the twisted wire brush inserts were found to be increased up to 2.15 and 2.0 times, respectively, than those over the plain tube values. Furthermore, the heat transfer performance was evaluated to assess the real benefits of using those type of inserts and the performance was achieved 1.85 times higher compared to the plain tube based on the constant blower power. Finally, correlations were developed based on the data generated from this work to predict the heat transfer, friction factor, and thermal performance factor for turbulent flow through a circular tube fitted with the twisted wire brush inserts in terms of wire density (y), Reynolds number (Re), and Prandtl number (Pr).  相似文献   
23.
The present study deals with numerical investigation of effects of different parameters on enhancement or retardation of the heat transfer rate in an annular vertical cylinder filled with saturated porous medium. The heat transfer is assumed to take place by mixed convection mode. The thermal non-equilibrium approach is considered. The inner surface of the annular cylinder is maintained at constant wall temperature whereas the outer surface remains at ambient temperature. The governing partial differential equations are solved using finite element method. The results are discussed for the effects of Peclet number, interphase heat transfer co-efficient and thermal conductivity ratio.  相似文献   
24.
Solar still is a simple device which can convert available waste or brackish water into potable water using solar energy. A single basin double slope solar still with an inner basin size 2.08 m × 0.84 m × 0.075 m and that of the outer basin size 2.3 m × 1 m × 0.25 m has been fabricated with mild steel plate and tested with a layer of water and different sensible heat storage materials like quartzite rock, red brick pieces, cement concrete pieces, washed stones and iron scraps. It is found that, the still with ¾ in. sized quartzite rock is the effective basin material. The still is theoretically modeled. In previous researcher’s work, variation in transmittance is taken as constant. The variations in solar incidence angle and transmittance of the covers are also considered in this work. The theoretical values are compared with actual values. The theoretical water and glass temperatures and the theoretical production rate are having higher deviation with actual. Hence, another thermal model developed for this still is applied to validate the results accurately. It is found that, the theoretical production rate using thermal model agrees well with experimental.  相似文献   
25.
The effect of laser energy density, during pulsed laser ablation, on the microstructure and optical properties of silicon films has been investigated using techniques such as atomic force microscopy, scanning electron microscopy, X-ray diffraction, and UV–visible absorption/transmission spectroscopy. The thickness of prepared films increases with increase in laser energy density. The crystallite size and hence the crystallinity of prepared films have been estimated by X-ray diffraction and found to be dependent on laser energy density. The transmittance of films changes with laser energy density. The absorption coefficient of films has been found to be?>104?cm?1 in wavelength region 450–1100?nm. The band gap of silicon films has been determined as 2.27, 2.11, and 1.90?eV corresponding to laser energy density of 1.5, 2.5, and 3.5?J?cm?2, respectively.  相似文献   
26.
Nafion hybrid membrane containing titanium dioxide (TiO2) nano-particles were elaborated by in situ sol–gel technique. Micro wave treatment was used during hybrid elaboration to 2 h. The X-ray diffraction (XRD) shows the crystallization of TiO2 in anatase and rutile phases. The Infrared spectroscopy IR spectrum of hybrid membranes Nafion–TiO2 confirm the presence of bonds Ti–O and Ti–OH which proves that the hybridization of the membrane by sol–gel method is successful. Atomic Force Microscopy AFM confirmed the good dispersion of TiO2 nano-particles. The electrochemical impedance spectroscopy (EIS) and solvent uptake measurements suggest the enhancement of the membrane performance.  相似文献   
27.
Kinetics of free radical polymerization of methyl methacrylate using potassium peroxomonosulfate as initiator in the presence of benzyltributylammonium chloride (BTBAC) as phase transfer catalyst was studied. The polymerization reactions were carried out under nitrogen atmosphere and unstirred conditions at a constant temperature of 60°C in ethyl acetate/water bi-phase system. The role of concentrations of monomer, initiator, catalyst, temperature, acid and ionic strength on the rate of polymerization (Rp) was ascertained. The orders with respect to monomer, initiator and phase transfer catalyst were found to be 1.5, 0.5 and 0.5 respectively. The rate of polymerization (Rp) is independent of ionic strength and pH. Based on the kinetic results, a suitable mechanism is proposed.  相似文献   
28.
This communication presents results of our 2-year survey on groundwater arsenic contamination in three districts Ballia, Varanasi and Gazipur of Uttar Pradesh (UP) in the upper and middle Ganga plain, India. Analyses of 4,780 tubewell water samples revealed that arsenic concentrations in 46.5% exceeded 10 microg/L, in 26.7%, 50 microg/L and in 10% 300 microg/L limits. Arsenic concentrations up to 3,192 microg//L were observed. The age of tubewells (n=1,881) ranged from less than a year to 32 years, with an average of 6.5 years. Our study shows that older tubewells had a greater chance of contamination. Depth of tubewells (n=3,810) varied from 6 to 60.5 m with a mean of 25.75 m. A detailed study in three administrative units within Ballia district, i.e. block, Gram Panchayet, and village was carried out to assess the magnitude of the contamination. Before our survey the affected villagers were not aware that they were suffering from arsenical toxicity through contaminated drinking water. A preliminary clinical examination in 11 affected villages (10 from Ballia and 1 from Gazipur district) revealed typical arsenical skin lesions ranging from melanosis, keratosis to Bowens (suspected). Out of 989 villagers (691 adults, and 298 children) screened, 137 (19.8%) of the adults and 17 (5.7%) of the children were diagnosed to have typical arsenical skin lesions. Arsenical neuropathy and adverse obstetric outcome were also observed, indicating severity of exposure. The range of arsenic concentrations in hair, nail and urine was 137-10,900, 764-19,700 microg/kg, and 23-4,030 microg/L, respectively. The urine, hair and nail concentrations of arsenic correlated significantly (r=0.76, 0.61, and 0.55, respectively) with drinking water arsenic concentrations. The similarity to previous studies on arsenic contamination in West Bengal, Bihar and Bangladesh indicates that people from a significant part of the surveyed areas in UP are suffering and this will spread unless drives to raise awareness of arsenic toxicity are undertaken and an arsenic safe water supply is immediately introduced.  相似文献   
29.
Fischer-Tropsch (FT) process has great potential to accomplish energy security but also for utilizing greenhouse gases to address the energy problem. Different kinds of feedstocks like coal, biomass (via gasification), CO2, methane (via reforming), and nonconventional energy sources are used to obtain the syn-gas (CO and H2). The formation of hydrocarbons in the FT process follows ASF distribution over the majority of the catalysts. It can be overcome by the application of a suitable catalyst, controlling the active metal interaction with the support and interaction of formed hydrocarbon with the support. The ratio of syn-gas is important to maintain the desired conversion and to have more selectivity towards C5+ products. Increase in the H2: CO ratios in the feed increases C5+ products and methane decreases. Whereas with the decrease in the ratios increases undesirable reactions and methane formation. In this article, we have discussed the recent literature from the viewpoint of increasing the C5+ selectivity. Support has a profound influence on product distribution. With the application of suitable support and controlling the interaction of the active sites yields the good CO conversion with fewer lighters and higher C5+ hydrocarbons.  相似文献   
30.
Multimedia Tools and Applications - Maintaining the optimum growth rate and estimating the concentration of microalgae are critical in improving microalgae production. An efficient concentration...  相似文献   
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