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41.
P.Subhadra Ramachandran M.N. Mathur S.K. Ojha 《International Journal of Engineering Science》1979,17(5):625-639
Van Dyke's singular perturbation technique has been used to study the heat transfer in the flow of a micropolar fluid past a curved surface with suction and injection. The conditions for similar solutions of the thermal boundary layer equations have been obtained. In addition to the usual “no slip” condition for velocity, the two types of boundary conditions used for microrotation are: (i) no relative spin on the boundary; (ii) the anti-symmetric part of the stress tensor vanishes at the boundary. The effect of suction or injection on velocity, microrotation, temperature, skin friction coefficient, wall couple stress coefficient, displacement and momentum thicknesses, rate of heat transfer and adiabatic wall temperature have been studied. It is observed that with the increase of injection velocity, the thickness of the boundary layer is increased and the local drag is reduced. A comparison with the results obtained for a Newtonian fluid reveals that the microelements present in the fluid reduce the velocity and frictional drag, and cool the boundary. 相似文献
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Zheng H Ojha PC McClean S Graham C Black ND Hughes JG Shaw C 《IEEE transactions on nanobioscience》2005,4(3):241-247
Peptides in the skin secretion of frogs have been studied for some time now because they frequently possess important biological activity such as antibiotic, antimicrobial, or anticancer properties. In this paper, we present a computational approach for measuring the degree of similarity between the entire peptide complement of the skin secretion of specimens from the same or different species. The first step in the analysis is the generation of a mass spectral profile from an experimental high-performance liquid chromatography/electrosparay ionization analysis of the sample. An "overlap" between the mass spectral profiles of different specimens is then proposed as a measure of their similarity. Analysis of specimens from three species of the genus Litoria, viz., L. Aurea, L. Caerulea, and L. Infrafrenata, and Rana Capito of genus Rana shows that the degree of similarity is highest between specimens from the same species, lower for specimens from different species of the same genus, and lowest between specimens from different genera. This indicates that comparison of skin peptide profiles (i.e., mass spectral profiles of skin secretion) is potentially a useful aid in the taxonomic study of amphibian species. 相似文献
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Five different selective surfaces coated with oxides of nickel, manganese, chromiUm, lead, am iron on galvanized iron substrate by electro-deposition or chemical method were studied for properties such as absorptivity, emissivity, temperature rise of the surface and stagnation air temperature. The properties of the surfaces which may change due to weather conditions were predicted by: subjecting the collector surfaces to accelerated tests. The best among them was found to be black nickel, followed by manganese, chromium, lead, and iron oxides. Black nickel and manganese surfaces were included in the solar drying system and their drying air temperatures recorded. With selective surfaces, a temperature rise between 250to 4sOC was observed depending on the surface (either manganese oxide or nickel oxide)., Hence high mo~sture content food crops can be dried in less than half the time using selective surface 相似文献
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Microstructural studies and mechanical properties of Al-CuAl2 eutectic alloys solidified over a heat pipe have been presented and discussed. The role of thermal undercooling produced by solidification over a heat pipe in controlling the microstructure has been highlighted. Tensile specimens fabricated from aligned cellular Al-CuAl2 eutectic regions are shown to have maximum strength at intermediate temperatures of 450 to 500 K. Variations in the relative plasticity of two constituent phases of the eutectic are held responsible for the temperature dependence of strength. 相似文献
45.
Salmonellosis is an important disease in humans and is associated with contaminated food, including pork products. Salmonella infection is invasive in humans, but it usually remains latent within the swine population, creating reservoirs for carcass contamination. Although abattoirs implement stringent procedures during carcass processing, some raw pork products still have Salmonella contamination. To reduce the presence of Salmonella, a dynamic picture of the pork production chain is needed that includes management practices aimed at health and welfare of swine and practices within swine operations that affect the environment and community health. Swine practices indirectly influence the spread of zoonotic enteric pathogens. Pathogens in food animals can escape detection, and critical control points often are missed. Preharvest growth of swine by enhancement of normal gut flora and targeting intestinal pathogens through nonantibiotic approaches might improve food safety and reduce antibiotic residues. In light of the threat posed by multidrug-resistant pathogens, old dogma is being revisited with optimism for potential utility in promoting pre- and postharvest pork safety. This review includes possible approaches that can be implemented in swine operations and postslaughter during pork processing with simultaneous omission of subtherapeutic antibiotics to control Salmonella. We emphasize the vital roles of the veterinarians, pig producers, industry, food research scientists, and government guidelines for the strategic implementation of approaches to Salmonella control across the pork production and processing chains. 相似文献
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Wireless Personal Communications - This paper investigate the effectiveness of the Empirical Mode Decomposition (EMD) based Power Spectrum analysis (PSA) technique to evaluate the Performance of... 相似文献
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Maitreyi Upadhyay Suneet K. Awasthi Laxmi Shiveshwari S. N. Shukla S. P. Ojha 《Journal of Superconductivity and Novel Magnetism》2015,28(7):1937-1942
By studying temperature-dependent dispersion characteristics and group velocity of 1D ternary photonic crystal (TPC) composed of dielectric-superconductor-dielectric materials, a thermally tunable band-stop filter which is capable of stopping unique wavelength channels without causing any interference amongst equally spaced wavelength channels of full width at half maximum of 1 nm each as per the requirement of wavelength division multiplexing standards adopted by the International Telecommunication Union specifying channel spacing in terms of frequency (wavelength) is suggested. The proposed structure can efficiently work as a two-channel wavelength selective switch for wavelength division multiplexing (WDM)-based all-optical networks. This study also gives theoretical insight to design some new kind of optical memories and tunable buffers which holds data temporary and have potential applications in modern communication systems. 相似文献