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1.
We considered the magnetohydrodynamic (MHD) free convective flow of an incompressible electrically conducting viscous fluid past an infinite vertical permeable porous plate with a uniform transverse magnetic field, heat source and chemical reaction in a rotating frame taking Hall current effects into account. The momentum equations for the fluid flow during absorbent medium are controlled by the Brinkman model. Through the undisturbed state, both the plate and fluid are in a rigid body rotation by the uniform angular velocity perpendicular to an infinite vertical plate. The perpendicular surface is subject to the homogeneous invariable suction at a right angle to it and the heat on the surface varies about a non-zero unvarying average whereas the warmth of complimentary flow is invariable. The systematic solutions of the velocity, temperature, and concentration distributions are acquired systematically by utilizing the perturbation method. The velocity expressions consist of steady-state and fluctuating situations. It is revealed that the steady part of the velocity field has a three-layer characteristic while the oscillatory part of the fluid field exhibits a multi-layer characteristic. The influence of various governing flow parameters on the velocity, temperature, and concentration are analyzed graphically. We also discuss computational results for the skin friction, Nusselt number, and Sherwood number in the tabular forms. 相似文献
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3.
Jagadeesh Babu Sriramoju Murthy Muniyappa Navya Rani Marilingaiah Chetana Sabbanahalli Manjunath Shetty Ravi Mudike Chitrabanu C.P Prasanna D. Shivaramu Nagaraju G Kanchugarakoppal S. Rangappa Ananda Kumar C.S Dinesh Rangappa 《Ceramics International》2021,47(7):10314-10321
Application of brown titanium dioxide (TiO2-x) and its modified composite forms in the photocatalytic decomposition of organic pollutants in the environment is a promising way to provide solutions for environmental redemption. Herein, we report the synthesis of effective and stable TiO2-x nanoparticles with g-C3N4, RGO, and multiwalled carbon nanotubes (CNTs) using a simple hydrothermal method. Among all the as-synthesized samples, excellent photocatalytic degradation activity was observed for RGO-TiO2-x nanocomposite with high rate constants of 0.075 min?1, 0.083 min?1 and 0.093 min?1 for methylene blue, rhodamine-B, and rosebengal dyes under UV–Visible light irradiation, respectively. The altered bandgap (1.8 eV) and the large surface area of RGO-TiO2-x nanocomposite impacts on both absorption of visible light and efficiency of photogenerated charge electron (e?)/hole (h+) pair separation. This resulted in enhanced photocatalytic property of carbon-based TiO2-x nanocomposites. A systematic study on the influence of different carbon nanostructures on the photocatalytic activity of brown TiO2-x is carried out. 相似文献
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The development of the semi-theoretical correlation in Hadzisdmajlovic et al. (1983) for predicting the maximum spoutable height in a spout-fluid bed, is observed to involve certain discrepancies. Based on their experimental data, a new correlation is proposed. 相似文献
6.
The partial substitution of Ga at the Cu(1) (chain) sites of the YBa2Cu3O7 structure allows synthesis at ambient pressure of Ba-free analogs, e.g., YSr2Cu2.7Ga0.3O7?δ . Materials with this composition have been found to be nonsuperconducting, but superconductivity has been induced by one or more of the following methods: Ca substitutions at the Y site; Ba substitutions at the Sr site; annealing in high-pressure oxygen. The influence of these chemical manipulations onT c has been monitored and all methods have been found to enhanceT c . The electronic effects of Ba substitutions have been deduced indirectly using powder neutron diffraction, and such substitutions appear to result in a redistribution of hole density into the Cu(1) sites from the superconducting CuO2 planes. 相似文献
7.
A.Varada Rajulu G. Babu Rao B. Ravi Prasad Rao A. Madhu Sudana Reddy Jiasong He Jun Zhang 《应用聚合物科学杂志》2002,84(12):2216-2221
Studies on some properties such as the density, the degradation temperatures, the morphology and the spectral features of the ligno‐cellulose fiber Hildegardia were carried out in both untreated and alkali treated form. The fibers are found to have good morphology and moderate initial and final degradation temperatures. On alkali treatment, the lignin was found to be eliminated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2216–2221, 2002 相似文献
8.
G. Babu Viswanathan Michael J. Mills Vijay K. Vasudevan 《Metallurgical and Materials Transactions A》2003,34(10):2113-2127
The effects of microstructure on the tensile properties and deformation behavior of a binary Ti-48Al gamma titanium aluminide
were studied. Tensile-mechanical properties of samples with microstructures ranging from near γ to duplex to fine grained, near- and fully-lamellar were determined at a range of temperatures, and the deformation structures
in these characterized by transmission electron microscopy (TEM). Microstructure was observed to exert a strong influence
on the tensile properties, with the grain size and lamellar volume fraction playing connected, but complex, roles. Acoustic
emission response monitored during the tensile test revealed spikes whose amplitude and frequency increased with an increase
in the volume fraction of lamellar grains in the microstructure. Analysis of failed samples suggested that microcracking was
the main factor responsible for the spikes, with twinning providing a minor contribution in the near-lamellar materials. The
most important factor that controls ductility of these alloys is grain size. The ductility, yield stress, and work-hardening
rate of the binary Ti-48Al alloy exhibit maximum values between 0.50 and 0.60 volume fraction of the lamellar constituent.
The high work-hardening rate, which is associated with the low mobility of dislocations, is the likely cause of low ductility
of these alloys. In the near-γ and duplex structures, slip by motion of 1/2<110] unit dislocations and twinning are the prevalent deformation modes at room
temperature (RT), whereas twinning is more common in the near- and fully-lamellar structures. The occurrence of twinning is
largely dictated by the Schmid factor. The 1/2<110] unit dislocations are prevalent even for grain orientations for which
the Schmid factor is higher for <101] superdislocations, though the latter are observed in favorably oriented grains. The
activity of both of these systems is responsible for the higher ductility at ambient temperatures compared with Al-rich single-phase
γ alloys. A higher twin density is observed in lamellar grains, but their propagation depends on the orientation and geometry
of the individual γ lamellae. The increase in ductility at high temperatures correlates with increased activity of 1/2<110] dislocations (including
their climb motion) and twin thickening. The role of microstructural variables on strength, ductility, and fracture are discussed.
This article is based on a presentation made in the symposium entitled “Fundamentals of Structural Intermetallics,” presented
at the 2002 TMS Annual Meeting, February 21–27, 2002, in Seattle, Washington, under the auspices of the ASM and TMS Joint
Committee on Mechanical Behavior of Materials. 相似文献
9.
C. Jeyachandrabose J. Kirkhope C. Ramesh Babu 《International journal for numerical methods in engineering》1985,21(7):1289-1293
The stiffness matrix for the DKT plate-bending element is formulated explicitly in a global co-ordinate system. This approach avoids transformations of stiffness, and elasticity properties for anisotropic materials, from local to global co-ordinates, which were required in previous formulations. A FORTRAN listing of the algorithm is appended for potential users. 相似文献
10.