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FLOW CONTROL THROUGH VORTEX SHEDDING INTERACTION OF ONE CYLINDER DOWNSTREAM OF ANOTHER
No full textABSTRACT: This study investigates the vortices produced between two 2d cylinders, and the relationship between the structures of the vortices produced at both cylinders when one is placed in the wake flow of another. CFD simulations using ANSYS Fluent were used to determine the coefficients of lift and drag, as well as the frequency of vortex shedding and size of vortices at three separate Reynolds numbers of 16000, 32000 and 65000 in different arrangements. Each arrangement of cylinders was compared against controls, which consisted of a single cylinder to determine the alteration of forces produced. Two trip wires at 7 different angles of 40, 45, 50, 55, 60, 65, and 70 degrees were then investigated at a Reynolds number of 65000 which was compared to the smooth cylinder control forces and frequency of vortex shedding. The most optimum angle of trip wires was then combined with linear cylinder arrangements also at a Reynolds number of 65000 for comparison with only the upstream cylinder utilizing the trip wires
Thermoelastic problem of a thin circular plate due to Heat generation
No full textABSTRACT-This Paper is concerned with transient thermoelastic problem of a thin circular plate occupying the space , with radiation type boundary conditions. In this paper an attempt has been made to determine the temperature distribution, displacement function and thermal stresses of a thin circular plate with the help of integral transform techniques. The result are obtained in terms Bessel's function in the form of infinite series and depicted graphically
Ultraviolet emission and Fano resonance in doped nano-alumina
No full textEmission properties of Al 2 O 3 nanopowders, synthesized by flame spray pyrolysis with Mg, Cr, and Sc dopants, are investigated, principally in the protein lysing range of 250-290 nm ͑UV-C band͒. As expected, point defect densities depend on crystal phase and irradiation history and strongly influence emission properties at short wavelengths. Ultraviolet and visible emission intensities of aggregated point defect centers change upon electron beam exposure at high current densities, but ultraviolet emission from point defects is persistently enhanced over a narrow range of Mg-doped Al 2 O 3 compositions slightly off spinel stoichiometry. At 40% Mg concentration, emission intensities at 320 nm rise by over an order of magnitude after beam exposure. Quantum efficiency for cathodoluminescence in the 250-300 nm range nevertheless remains low. Point defect ionization at high currents shifts the emission of Al 2 O 3 nanopowders to the infrared and is shown to be correlated with a ubiquitous Fano resonance in ionized Cr-vacancy complexes. This base line spectroscopy permits us to attribute the very high quantum efficiency of UV-C luminescence in annealed Sc 3+ :Al 2 O 3 primarily to the formation of ␣-phase Al 2 O 3
Stellar and Laboratory XUV/EUV Line Ratios inFe XVIII and Fe XIX Stellar and laboratory XUV/EUV line ratios in Fe XVIII and Fe XIX
No full textAbstract. A so-called XUV excess has been suspected with the relative fluxes of Fe XVIII and Fe XIX lines observed in the XUV and EUV ranges of the spectrum of the star Capella as observed by the Chandra spacecraft, even after correction for interstellar absorption. This excess becomes apparent in the comparison of the observations with simulations of stellar spectra obtained using collisional-radiative models that employ, for example, the Atomic Plasma Emission Code (APEC) or the Flexible Atomic Code (FAC). We have addressed this problem by laboratory studies using the Livermore electron beam ion trap (EBIT)
Effect of Antimicrobial Peptide-Amide: Indolicidin on Biological Membranes
No full textIndolicidin, a cationic antimicrobial tridecapeptide amide, is rich in proline and tryptophan residues. Its biological activity is intensively studied, but the details how indolicidin interacts with membranes are not fully understood yet. We report here an in situ atomic force microscopic study describing the effect of indolicidin on an artificial supported planar bilayer membrane of dipalmitoyl phosphatidylcholine (DPPC) and on purple membrane of Halobacterium salinarum. Concentration dependent interaction of the peptide and membranes was found in case of DPPC resulting the destruction of the membrane. Purple membrane was much more resistant against indolicidin, probably due to its high protein content. Indolicidin preferred the border of membrane disks, where the lipids are more accessible. These data suggest that the atomic force microscope is a powerful tool in the study of indolicidin-membrane interaction
Interrogating Psycho-Social Problems of Muslim Women The Indian Experience
No full textAbstract The present paper is an endeavour to examine and emphasize the issues of psycho-social circumstances of Indian Muslim women in sociological perspective with special indication to their socio-economic, employment, educational attainment, rights and privileges, hindrances and restrictions, role Introduction The all-round development of a nation largely depends upon strapping up the skilfulness and abilities of all segments of society regardless of of caste, class, colour, creed and of course sexual category. On the other hand women discriminated against for ages and also have been suffering from given unequal treatment in connection with prospects, privileges, rights and status in numerous socio-economic and cultural spheres in the society. Devoid of concerning women in the programmes and performances of development, not simply obstruct their own development, social change and mobility towards social progress but also have an effect on the development of the entire nation (Azim 1997, 11). The concern of women's studies, having its fundamental objective to accumulate information on women and to explore their social position as well as problems and prospects, is attaining a great deal of magnitude during recent times in social scientific research and discourse. The ultimate objective of this sort of study is to empower the women in their movement for liberation and struggle in opposition to inequity. Again despite the fact that owing to divergence in culture and tradition, the status of women differs from society to society. In this regard women's studies have also an immense importance in generating awareness about the multi-dimensional roles played by the women and their diverse social position in diverse societies from an empirical point of view. Taking into consideration the theoretical and methodological outlooks of the studies of women, the subject is prevalently designated as gender studies instead of women's studies in contemporary time. Gender is a socially constructed roles, responsibilities and relations which are assigned to both men and women in the society creating inequities among them and the key subject matter o
Electric transport properties of Pt/Permalloy bilayers in the presence of an external magnetic field
No full textA recent experimental study of the electric properties of Pt/Permalloy bilayers based on a simultaneous application of an in-plane microfrequency current and an external magnetic field is simulated on a fully relativistic ab initio level by considering the resistivity as an implicit function of the free energy. It is found that the oscillations detected experimentally are caused by the different behavior of out-of-plane and in-plane resistivities in the vicinity of that value of the free energy that corresponds to the resonant field induced by the applied current. A necessary precondition for such oscillations is a sizeable perpendicular anisotropy, which is not the case in systems consisting only of Permalloy. It is shown that the observed phenomenon is essentially an interface effect