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41.
BACKGROUND: Ten isolates of anaerobic fungi of Piromyces genus from wild cattle and blue bulls (five isolates from each host species) were evaluated for their fibrolytic ability in pure culture, their suitability for use as a microbial additive in buffaloes and their effect on methane emission. RESULTS: In pure culture, only two out of five isolates from wild cattle degraded wheat straw efficiently, whereas all five isolates from wild blue bulls did. Isolate CF1 (from cattle) showed the highest apparent digestibility (53.4%), true digestibility (70.8%) and neutral detergent fibre digestibility (75.0%) of wheat straw after 5 days of incubation. When added to buffalo rumen fluid, all five isolates from cattle increased (P < 0.05) in vitro apparent digestibility of wheat straw compared with the control (received autoclaved culture), but all five isolates from blue bulls failed to influence in vitro digestibility of wheat straw. Isolate CF1 showed the highest stimulating effect on straw digestion by buffalo rumen fluid microbes and increased apparent digestibility (51.9 vs 29.4%, P < 0.05), true digestibility (57.9 vs 36.5%, P < 0.05) and neutral detergent fibre digestibility (51.5 vs 26.9%, P < 0.05) of wheat straw compared with the control after 24 h of fermentation. There were also significant increases in fungal count and enzyme activities of carboxymethylcellulase and xylanase in the CF1‐added group compared with the control group. Gas and methane production g?1 truly digested dry matter of straw were comparable among all groups including the control. CONCLUSION: Wild cattle and blue bulls harbour some anaerobic fungal strains with strong capability to hydrolyse fibre. The fungal isolate CF1 has high potential for use as a microbial feed additive in buffaloes to improve digestibility of fibrous feeds without increasing methane emission per unit of digested feed. Copyright © 2010 Society of Chemical Industry  相似文献   
42.
Mohan Lal Khanna 《Solar Energy》1967,11(3-4):142-144
An arrangement for heating with solar energy by means of a heat exchanger and storage coupled to the two water heaters has been described*. In the present paper, the amount of the heat transferred from water to air in the shell-and-tube heat exchanger and the temperature of the outgoing air have been estimated by considering various parameters, viz. flow rate and temperature of incoming air, temperature of incoming and outgoing water, length and diameter of tubes, etc. Both natural and forced convection mode of heat transfer have been considered.

Under boundary conditions of free convection, heat transfer would be rapid and efficient with a possible reduction in the pipe length. The maximum permissible limit of pressure drop per foot of each tube for pipes of different diameters at different Reynolds numbers has been given.

As conditions of drying vary from material to material, the data presented will help in arriving at the final design of the shell-and-tube heat exchanger to be used in drying a particular material.  相似文献   

43.
Increasing consumer desire for high quality ready-to-eat foods makes thermal pasteurization important to both food producers and researchers. To be in compliance with the Food Safety Modernization Act (FSMA), food companies seek regulatory and scientific guidelines to ensure that their products are safe. Clearly understanding the regulations for chilled or frozen foods is of fundamental importance to the design of thermal pasteurization processes for vegetables that meet food safety requirements. This article provides an overview of the current regulations and guidelines for pasteurization in the U.S. and in Europe for control of bacterial pathogens. Poorly understood viral pathogens, in terms of their survival in thermal treatments, are an increasing concern for both food safety regulators and scientists. New data on heat resistance of viruses in different foods are summarized. Food quality attributes are sensitive to thermal degradation. A review of thermal kinetics of inactivation of quality-related enzymes in vegetables and the effects of thermal pasteurization on vegetable quality is presented. The review also discusses shelf-life of thermally pasteurized vegetables.  相似文献   
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Attenuated total reflectance–Fourier transform infrared spectroscopy, along with chemometrics, were used to detect and quantify soya bean oil (SO) and sugar (CS) adulteration in milk. Bovine milk was artificially adulterated with SO (0.2–2.0%; v/v) and CS (1–10%; w/v) separately. Spectra revealed significant differences in specific wavenumber regions (SO: 1450–1250 cm?1; CS: 1200–900 cm?1). Soya bean oil adulteration was best predicted in wavenumber range of 1262–1164 cm?1, using partial least square regression (coefficient of determination (R2: 0.90 and 0.88 for calibration and validation, respectively). Common sugar adulteration was best predicted in wavenumber range of 1010–910 cm?1 (R2: 0.99 for calibration and validation) using partial least square.  相似文献   
47.
This study represents a comprehensive analysis and scientific validation of our ancient knowledge about the ethnopharmacological aspects of cow urine by measuring the lipid peroxidation, radical scavenging, and level of reduced glutathione and catalase activity. Graded doses of cow urine were administered orally to experimentally treated rats. Results of liver and plasma from experimentally treated rats indicated that cow urine reduced the levels of thiobarbituric acid reactive substance significantly in all the treatments (P < 0.01). In vitro experiments with the liver of control and experimentally treated rats were also carried out against cumene hydroperoxide-induced lipid peroxidation. On LCMS analysis, the antioxidant component of cow urine was identified as uric acid (m/z 169.07). The results demonstrate that the cow urine-mediated induction of antioxidant level controls oxidative damage, even after minimal processing, and thus is indicative of its potential as a viable substitute of synthetic antioxidants.  相似文献   
48.
Solidification/stabilization of toxic pentachlorophenol (PCP) has been studied by using spectroscopic and electrochemical techniques. Portland type I c  相似文献   
49.
A spray drying approach was used to apply 15-nm-thick SiO2 continuous coatings onto ZnS:Ag phosphor particles. A prehydrolyzed TEOS dip coating formula was used as the SiO2 precursor. The phosphor was mixed together with the precursor then atomized without allowing gelation to occur until the droplets containing the particles were in flight. The coating gelled and dried while falling through a graded heat zone. The dried coated particles were captured in a cyclone separator and heat-treated to further densify the SiO2 coating. The coatings protected the phosphors while in service in field emission display (FED) devices.  相似文献   
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