681 research outputs found

    Flow prediction for propfan engine installation effects on transport aircraft at transonic speeds

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    An Euler-based method for aerodynamic analysis of turboprop transport aircraft at transonic speeds has been developed. In this method, inviscid Euler equations are solved over surface-fitted grids constructed about aircraft configurations. Propeller effects are simulated by specifying sources of momentum and energy on an actuator disc located in place of the propeller. A stripwise boundary layer procedure is included to account for the viscous effects. A preliminary version of an approach to embed the exhaust plume within the global Euler solution has also been developed for more accurate treatment of the exhaust flow. The resulting system of programs is capable of handling wing-body-nacelle-propeller configurations. The propeller disks may be tractors or pushers and may represent single or counterrotation propellers. Results from analyses of three test cases of interest (a wing alone, a wing-body-nacelle model, and a wing-nacelle-endplate model) are presented. A user's manual for executing the system of computer programs with formats of various input files, sample job decks, and sample input files is provided in appendices

    Relative oral bioavailability of three formulations of vitamin D3: An open-label, three-treatment study

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    Background: Supplementation of vitamin D2 or vitamin D3 is recommended for vitamin D deficiency. Weekly supplementation of 60,000 IU of vitamin D3 increases serum 25(OH) D to optimal values. Various marketed forms of vitamin D3 include tablets, capsule, granules and oral solution. The main objective of this study is to compare the relative bioavailability of vitamin D3 oral solution with vitamin D3 tablet and capsule.Methods: This is an open-label, randomized, single-dose, three-treatment study to compare the relative bioavailability of vitamin D3 oral solution with capsule and tablet. Subjects (n=70) were supplemented with single dose of one of these formulations and their blood sample were assessed for Cmax, AUC0-28d and Tmax.Results: The logarithmic transformed data of pharmacokinetic parameters were analyzed for 90% Confidence Intervals (CI) using ANOVA. The mean (90% CI) values of vitamin D3 oral solution against tablet for the ratio of Cmax and AUC0-28d were 113.00 (105.32-121.23) and 105.54 (97.95-113.72) respectively. The mean (90% CI) values of vitamin D3 oral solution against capsule for the ratio of Cmax and AUC0-28d were 115.02 (106.38 - 124.37) and 112.33 (104.44 - 120.81) respectively. These values were within the bioequivalence range of 80-125%.Conclusions: It is concluded that vitamin D3 Oral Solution formulated with nanotechnology is bioequivalent to vitamin D3 tablet and capsule. However, oral solution of vitamin D3 shows higher Cmax and AUC when compared to tablet and capsule formulations

    Heusler-based synthetic antiferrimagnets

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    Antiferromagnet spintronic devices eliminate or mitigate long-range dipolar fields, thereby promising ultrafast operation. For spin transport electronics, one of the most successful strategies is the creation of metallic synthetic antiferromagnets, which, to date, have largely been formed from transition metals and their alloys. Here, we show that synthetic antiferrimagnetic sandwiches can be formed using exchange coupling spacer layers composed of atomically ordered RuAl layers and ultrathin, perpendicularly magnetized, tetragonal ferrimagnetic Heusler layers. Chemically ordered RuAl layers can both be grown on top of a Heusler layer and allow for the growth of ordered Heusler layers deposited on top of it that are as thin as one unit cell. The RuAl spacer layer gives rise to a thickness-dependent oscillatory interlayer coupling with an oscillation period of ~1.1 nm. The observation of ultrathin ordered synthetic antiferrimagnets substantially expands the family of synthetic antiferromagnets and magnetic compounds for spintronic technologies

    Proposal for creating a centre for research in solar-terrestrial physics as an interdepartmental activity during IHY at Shivaji University, Kolhapur (16.40°N, 74.15°E)

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    This note describes teaching and R & D activities presently being carried out in the solar-terrestrial Physics at the Space Science laboratory, Department of Physics, Shivaji University, Kolhapur. A variety of solar and geophysical ground based experiments are available, which can be operated on a regular basis during IHY, with financial help from the government funding agencies in India. The main purpose of this note is to briefly describe our experimental research facilities of relevance to IHY

    TranAir: A full-potential, solution-adaptive, rectangular grid code for predicting subsonic, transonic, and supersonic flows about arbitrary configurations. User's manual

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    The TranAir computer program calculates transonic flow about arbitrary configurations at subsonic, transonic, and supersonic freestream Mach numbers. TranAir solves the nonlinear full potential equations subject to a variety of boundary conditions modeling wakes, inlets, exhausts, porous walls, and impermeable surfaces. Regions with different total temperature and pressure can be represented. The user's manual describes how to run the TranAir program and its graphical support programs

    Effect of varying concentrations of salinity on some biochemical parameters involved in nitrogen metabolism of four grass species

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    ABSTRACT: Salinity adversely affects crop productivity and the quality of yield. The present work was carried out to estimate the changes in nitrogen metabolism under the influence of NaCl salinity in four selected grasses. All the species recorded a decrease in nitrate nitrogen content at the highest concentration of salinity stress (300 mM). Its maximum increase was 14 and 19% (100 mM) for Cymbopogon nardus and Cynodon dactylon, respectively. The maximum increase in nitrite nitrogen found was 11% (200 mM) in Cymbopogon nardus, 12% (100 mM) in Cynodon dactylon. The concentration of proline and amides in the leaves of all the experimental grasses showed a positive correlation with increasing concentrations of salinity. The maximum increase in proline content was 81, 88, 126, and 68% in Cymbopogon nardus, Cynodon dactylon, Pennisetum alopecuroides, and Vetiveria zizanioides, respectively, at 300 mM NaCl salinity. The concentration of free amino acids in the leaves of all the experimental grasses was considerably increased under saline condition and showed a positive correlation with increasing concentrations of salinity. Similar results were obtained in the case of amides. The concentration of nitrate reductase enzyme was elevated in Cymbopogon nardus and Pennisetum alopecuroides at lower salinity regime

    Breakup of 42 MeV <SUP>7</SUP>Li projectiles in the fields of <SUP>12</SUP>C and <SUP>197</SUP>Au nuclei

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    Inclusive cross sections of a particles and tritons from the breakup of 42 MeV 7Li by 12C and 197Au targets are presented and analysed in the framework of the Serber model. Spectral distortions due to the targets and relevant reaction mechanisms are discussed
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