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981.
P. Kandaswamy Jinho Lee A.K. Abdul Hakeem S. Saravanan 《International Journal of Heat and Mass Transfer》2008,51(7-8):1830-1837
Buoyancy driven convection in a square cavity induced by two mutually orthogonal and arbitrarily located baffles is studied numerically. The baffles are of different sizes and the flow is two-dimensional. The coupled governing equations were solved by finite difference method using Alternating Direction Implicit technique and Successive Over-Relaxation method. The steady state results are presented in the form of streamline and isotherm plots. It is found that buoyancy force plays a key role and overall heat transfer in the cavity is enhanced for higher values of both baffle–cavity ratios. Flow inhibition emerges as a deciding factor and diminishes heat transfer when the horizontal baffle is located above the center of the cavity. 相似文献
982.
983.
Golandaj Ajij J. Mahomed Abdul S. Singh Sooboo Friedrich Holger B. 《Journal of Porous Materials》2015,22(3):787-796
Journal of Porous Materials - This study examines the effect of different weight loadings of molybdenum as molybdenum oxide, supported on SBA-15 for the oxidative dehydrogenation of n-octane. The... 相似文献
984.
Nurul Aini Mohamed Razali Keat Teong Lee Subhash Bhatia Abdul Rahman Mohamed 《Renewable & Sustainable Energy Reviews》2012,16(7):4951-4964
The utilization of CO2 for the production of useful chemicals using heterogeneous catalysts is one of the ways to reduce the anthropogenic greenhouse gases in the atmosphere. In many cases, the CO2 conversion and products yield are still considered very low and need to be operated at high pressure and temperature. The critical point in CO2 conversion is to activate the CO2 molecules either by adding a co-reactant or by using effective catalysts. This paper presents the current development on the effect of several precursors like metals, metal oxides, ionic liquids, and acid–base loaded on a suitable support in creating magical properties of catalysts on the performance of CO2 conversion. Cu/ZnO-based catalysts, ionic liquid-based catalysts, and metal oxides-based catalysts are reported to be the most effective catalysts in the formation of methanol, cyclic carbonates and dimethyl carbonate. This review also focuses on various strategies and developments in altering heterogeneous catalysts, followed by critical factors of CO2 molecule activation, and the optimization of the catalytic activity or catalysts reusability. 相似文献
985.
The increasing demand for storage, networking and computation has driven intensification of large complex data centers that run many of today's Internet, financial, commercial and business applications. A data center comprises of many thousands of servers and can use as much energy as small city. Massive amount of computation power is required to drive and run these server farms resulting in many challenging like huge energy consumptions, emission of green house gases, backups and recovery; This paper proposes energy efficiency and low carbon enabler green IT framework for these large and complex server farms to save consumption of electricity and reduce the emission of green house gases to lower the effects of global warming. The framework uses latest energy saving techniques like virtualization, cloud computing and green metrics to achieve greener data centers. It comprises of five phase to properly implement green IT techniques to achieve green data centers. The proposed framework seamlessly divides data center components into different resource pools and then applies green metrics like Power Usage Effectiveness, Data Center Effectiveness and Carbon Emission Calculator to measure performance of individual components so that benchmarking values can be achieved and set as standard to be followed by data centers. 相似文献
986.
Samiullah Khan Aziz Ullah Kaleem Ullah Nisar-ur Rehman 《Designed Monomers and Polymers》2016,19(5):456-478
The development and introduction of injectable biomaterials and the identification of methods through which materials may form in situ are currently the topics of interest in materials science, specifically in the field of biomaterials. Over the last few decades, hydrogels which refers to the swellable polymeric matrices have gained wide attention due to their excellent characteristics such as swelling in different media, pH and temperature sensitivity, and sensitivity to other stimuli. Nowadays, injectable hydrogels have widely been studied due to their excellent insitu gelation at body temperature. These injectable insitu gels serve as depot system which ensures the local and systemic drug and gene delivery. These insitu gels also protect the proteins and peptide drugs invivo from environmental effect. The current review is made to report latest extensive literature regarding hydrogels, their classification, synthesis methods, structure of hydrogel network, methods of crosslinking, environment-sensitive hydrogel system, drug loading, and release, hydrogels as biosensors and applications of hydrogels. 相似文献
987.
Nazim Abdul Nariman 《Frontiers of Structural and Civil Engineering》2017,11(1):66-89
This paper studies optimization of three design parameters (mass ratio, frequency ratio and damping ratio) of multiple tuned mass dampers MTMDs that are applied in a cable stayed bridge excited by a strong wind using minimax optimization technique. ABAQUS finite element program is utilized to run numerical simulations with the support of MATLAB codes and Fast Fourier Transform FFT technique. The optimum values of these three parameters are validated with two benchmarks from the literature, first with Wang and coauthors and then with Lin and coauthors. The validation procedure detected a good agreement between the results. Box-Behnken experimental method is dedicated to formulate the surrogate models to represent the control efficiency of the vertical and torsional vibrations. Sobol’s sensitivity indices are calculated for the design parameters in addition to their interaction orders. The optimization results revealed better performance of the MTMDs in controlling the vertical and the torsional vibrations for higher mode shapes. Furthermore, the calculated rational effects of each design parameter facilitate to increase the control efficiency of the MTMDs in conjunction with the support of the surrogate models. 相似文献
988.
Ghalib ul Islam Munawar Iqbal Abdul Rehman Zusheng Zhou 《Instruments and Experimental Techniques》2017,60(1):87-90
We present the design analysis of a point focused electron beam emitter using numerical techniques. Simulation and modeling were performed followed by the calculation of emission parameters using programming codes EGUN and CST-PS. Beam emittance, average current density and perveance were calculated and are in agreement with the experimental values obtained at 10 kV acceleration potential. The emission parameters were evaluated up to 110 kV. This confirms possibilities of potential application of emitter for a linear accelerator. 相似文献
989.
Ali Yassoralipour Jamilah Bakar Russly Abdul Rahman Fatimah Abu Bakar 《International Journal of Food Properties》2016,19(12):2707-2717
The purpose of this study was to investigate the effect of packaging film on physicochemical properties, microbial profile, and biogenic amines content of barramundi (Lates calcarifer Bloch) fillets packed in polyamide, polypropylene, and low-density polyethylene films and kept at 8°C more than 20 days under modified atmosphere packaging. Putrescine and cadaverine were the most abundant amines, whereas the concentration of histamine ranged from less than 0.5 (not detected) to 198.0, 264.3, and 308.5 mg/kg for polyamide, polypropylene, and polyethylene (low-density polyethylene) films, respectively. Among the three, the psychrotrophic bacteria count was initially 4.26 log colony forming units/g and exceeded the acceptable limit of 7 log colony forming units/g on the 16th day of storage for polyamide and on 12th day of storage for polypropylene and polyethylene. However, the total plate count, among the three packaging films, was initially 3.54 log colony forming units/g and exceeded the acceptable limit of 6 log colony forming units/g on the 12th day of storage. The histamine-forming bacteria count was significantly (p < 0.05) lower in barramundi fillets packaged with polyamide compared to polypropylene and polyethylene. The significant difference (p < 0.05) was observed between the concentration of amines in polyamide as compared with polypropylene and polyethylene. Among the three packaging materials, polyamide was found to be the best for prolonging the storage of barramundi fillets. 相似文献
990.