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1.
Kumar A. Madhan Ehsan Muhammad Ali Suleiman Rami K. Hakeem Abbas Saeed 《Metallurgical and Materials Transactions A》2020,51(8):4301-4312
Metallurgical and Materials Transactions A - The surface of implant materials is one of the most significant factors for controlling the interaction between biomaterials and bone tissues. Hence,... 相似文献
2.
Wireless Networks - Vehicular communication is one of the critical technologies in intelligent transportation system to provide connectivity between vehicles, road side units, and pedestrians.... 相似文献
3.
Sadaqat Ali Bilal Anjum Ahmed Hafiz Muzammil Irshad Akolade Idris Bakare Abbas Saeed Hakeem Muhammad Qamaruddin Muhammad Ali Ehsan Sameer Ali Muhammad Umar Azam 《International Journal of Applied Ceramic Technology》2020,17(4):1948-1958
The thermomechanical behavior of micro/nano-alumina (Al2O3) ceramics reinforced with 1-5 wt.% of acid-treated oil fly ash (OFA) was investigated. Composites were sintered using spark plasma sintering (SPS) technique at a temperature of 1400°C by applying a constant uniaxial pressure of 50 MPa. It was evaluated that the fracture toughness of micro- and nanosized composites improved in contrast with the monolithic alumina. Highest fracture toughness value of 4.85 MPam1/2 was measured for the nanosized composite reinforced with 5 wt.% OFA. The thermal conductivity of the composites (nano-/microsized) decreased with the increase in temperature. However, the addition of OFA (1-5 wt.%) in nanosized alumina enhanced the thermal conductivity at an evaluated temperature. Furthermore, a minimum thermal expansion value of 6.17 ppm*K−1 was measured for nanosized Al2O3/5 wt.% OFA composite. Microstructural characterization of Al2O3-OFA composites was done by x-ray diffraction and Raman spectroscopy. Oil fly ash particles were seen to be well dispersed within the alumina matrix. Moreover, the comparative analysis of the nano-/microsized Al2O3/OFA composites shows that the mechanical and thermal properties were improved in nanosized alumina composites. 相似文献
4.
Silicon - Silicon (Si) is very effective in the amelioration of heavy metal (HM) stress in different crop plants. This investigation was conducted to assess the protective role of Si in modulating... 相似文献
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Laminar free convection induced by two mutually orthogonal discrete heat-generating baffles in a two-dimensional square cavity is analyzed numerically. The computations were carried out for different locations and combinations of heat source strengths of the baffles for a fixed Grashof number of 106and Prandtl number of 0.71. The coupled governing equations were solved bya finite-difference method using alternating direction implicit technique and successive overrelaxation methods. The obtained results clearly show that the hydrodynamic and thermal fields in the cavity depend on both the location and strength of the heat-generating baffles. Though the flow inhibition is caused by both the baffles, the baffle with higher source strength plays a decisive role in inducing the flow. The locations of baffles with unequal source strengths produce significant changes in the net heat transfer rate. This is further magnified for higher contrast in source strengths. This study provides qualitative suggestions that may improve the thermal design of sealed enclosures, which are encountered frequently in the electronics industry. 相似文献
6.
K. Park H.Y. Hong G.W. Jung D.H. Kim D.A. Hakeem A. Iqbal 《Ceramics International》2018,44(13):15024-15034
Fe2-xAgxO3 (0?≤?x?≤?0.04) nanopowders with various Ag contents were synthesized at different hydrothermal reaction temperatures (150?°C and 180?°C). Their structural properties were fully investigated through an X-ray diffraction, a Fourier transform infrared spectroscopy, and an X-ray photoelectron spectroscopy. The hydrothermal reaction temperature, time, and Ag content remarkably affected the morphological characteristics and crystal structure of the synthesized powders. The Fe2-xAgxO3 (0?≤?x?≤?0.04) powders synthesized at 150?°C for 6?h and the Fe2-xAgxO3 (0.02?≤?x?≤?0.04) powders synthesized at 180?°C for 12?h formed the orthorhombic α-FeOOH phase with a rod-like morphology, whereas the Fe2-xAgxO3 (0?≤?x?≤?0.01) powders synthesized at 180?°C for 12?h formed the rhombohedral α-Fe2O3 phase with a spherical-like morphology. The Fe1.98Ag0.02O3 fabricated by utilizing Fe1.98Ag0.02O3 powders synthesized at 180?°C showed the largest power factor (0.64?×10?5 Wm?1 K?2) and dimensionless figure-of-merit (0.0036) at 800?°C. 相似文献
7.
Abbas Saeed Hakeem Jekabs Grins Saeid Esmaeilzadeh 《Journal of the European Ceramic Society》2007,27(16):4783-4787
Vickers hardness and refractive index have been determined for a series of La-Si-O-N oxy-nitride glasses containing 30–62 e/o of La and 9–68 e/o of N. The hardness varies between 7.7 and 11.5 GPa at a load of 1 kg and is dependent of the N content, while the La content does not influence it significantly. The increase of the hardness with N content is, contrary to reported findings for other oxy-nitride glasses, found not to be linear over the whole compositional range. The refractive index varies between 1.8 and 2.3 and increases non-linearly with increasing N content. The compositional variations of hardness and refractive index are compared with previously published results. 相似文献
8.
Friction and wear behavior of Al6061 monolithic alloy and 1 wt% CNTs reinforced Al6061 composite prepared through ball milling and spark plasma sintering was investigated. It was found that, under mild wear conditions, the composite displayed lower wear rate and friction coefficient compared to the monolithic alloy. However, for severe wear conditions, the composite displayed higher wear rate and friction coefficient compared to the monolithic alloy. Analysis of worn surfaces revealed that, at lower loads, abrasion was the dominant wear mechanism for both materials. At higher loads, adhesion was found to be dominant for the monolithic alloy while excessive sub-surface fracturing and delamination were mainly observed for the composite. Also, it was clarified that the friction and wear behavior of Al–CNT composites is largely influenced by the applied load and there exists a critical load beyond which CNTs could have a negative impact on the wear resistance of aluminum alloy. 相似文献
9.
S. Saranya P. Ragupathi B. Ganga R.P. Sharma A.K. Abdul Hakeem 《Advanced Powder Technology》2018,29(9):1977-1990
This work investigates the two-dimensional steady convective boundary layer flow and heat transfer of Newtonian/non-Newtonian base fluids with magnetic/non-magnetic nanoparticles over a flat plate which incorporates non-linear thermal radiation and slip effects. We considered magnetite and aluminium oxide as magnetic and non-magnetic nanoparticles suspending inside the two sorts of base fluids specifically Water and Sodium Alginate. For physical significance we analyzed the behavior on non-Newtonian profiles by employing Casson model individually. The particular intrigue lies in looking the impacts of non-linear thermal radiation on the behavior of the flow. The solution of wide class of boundary value problems are facilitated by the change of the partial differential equations administering the flow utilizing similarity transformations into ordinary differential equations. The ODE’s are numerically handled by applying fourth order Runge-Kutta integration scheme in association with shooting procedure. The novel results for the dimensionless velocity and temperature inside the boundary layer are exhibited graphically for various parameters that describe the flow. A graphical demonstration is given for the skin friction coefficient and the local Nusselt number. 相似文献
10.
C. S. Murthy P. V. Raju S. Jonna K. Abdul Hakeem S. Thiruvengadachari 《International journal of remote sensing》2013,34(15):2865-2876
Spatial information on crop calendars in the command areas of irrigation systems is useful to irrigation engineers in order to achieve chronological synchronization between water delivery pattern and crop life cycle. Such synchronization is vital for efficient use of water. The capability of satellite remote sensing technology to generate spatial crop calendar information in an irrigated command area and its usefulness in the evaluation of water delivery patterns are demonstrated in this paper. The study pertains to the major crop paddy during the rabi season (December to June) of 1992-93, in the Bhadra project command area of Karnataka state, India. Analyses of multidate Normalized Difference Vegetation Index (NDVI) profiles of paddy crop generated from Indian Remote Sensing (IRS) satellite data for each distributary command reveal three distinct growth patterns in the study area with each pattern characterized by a particular crop calendar. The spatial variability in crop calendar over the total command area has thus been derived. The ground truth data obtained in crop cutting experiments (CCEs) validate the satellite derived crop calendar. Distributary wise, water delivery data have been studied in conjunction with the satellite derived crop calendar to determine whether the existing pattern of water delivery covers the required length of crop life cycle in the command area. It was found that the water supply was stopped about 30 days before harvesting in some distributaries and in some about 20-30 days before harvesting. A list of distributaries with greater lags between cessation of water supply and crop harvest was provided to irrigation system engineers to aid their plans for providing a reliable and predictable irrigation service. This is possible either through reorganization of canal operation schedule or through educating farmers about the need for adjusting their agricultural activities to match water supply patterns. 相似文献