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101.
P. Muthukumar Kishore Singh PatelPratik Sachan Nished Singhal 《International Journal of Hydrogen Energy》2012
A mathematical model for predicting the performances of a three-stage metal hydride based hydrogen compressor (MHHC) is presented. The performance of the MHHC is predicted by solving the unsteady heat and mass transfer characteristics of the coupled metal hydride beds of cylindrical configuration. The governing equations for energy, momentum and mass conservations, and reaction kinetic equations are solved simultaneously using the finite volume method. Metal hydrides chosen for a three-stage MHHC are LaNi5, MmNi4.6Al0.4 and Ti0.99Zr0.01V0.43Fe0.99Cr0.05Mn1.5. Numerical results obtained for a single-stage MHHC using MmNi4.6Al0.4 are in good agreement with the experimental data reported in the literature. Using three-stage compression, a maximum pressure ratio of 28 is achieved for the supply conditions of 20 °C absorption temperature and 2.5 bar supply pressure. A maximum delivery pressure of 100 bar is obtained for the operating conditions of 20 °C absorption temperature and 120 °C desorption temperature. 相似文献
102.
Product mix determination in the presence of alternate process plans and stochastic demand 总被引:3,自引:0,他引:3
Raja G. Kasilingam 《Computers & Industrial Engineering》1995,29(1-4):249-253
The product mix problem in the presence of alternate process plans under uncertain demand is formulated as a non-linear programming model. A heuristic solution procedure based on lagrangean relaxation technique is also presented. 相似文献
103.
One approach to aberration compensation of an imaging system is to introduce a suitable phase mask at the aperture plane of an imaging system. We utilize this principle for the compensation of astigmatism. A suitable polarization mask used on the aperture plane together with a polarizer-retarder combination at the input of the imaging system provides the compensating polarization-induced phase steps at different quadrants of the apertures masked by different polarizers. The aberrant phase can be considerably compensated by the proper choice of a polarization mask and suitable selection of the polarization parameters involved. The results presented here bear out our theoretical expectation. 相似文献
104.
Detailed statistical trend analysis of thermoplastic elastomers based on poly (phenylene ether) (PPE), polystyrene (PS), ethylene vinyl acetate (EVA) and styrene‐ethylene‐butylene‐styrene (SEBS) was done through Design Expert software by Stat‐Ease. D optimal crossed design was followed to capture the interaction with the parameters. Effect of blend ratio, vinyl acetate (VA) content of EVA, molecular weight (MW) of SEBS and intrinsic viscosity (IV) of PPE on the blend performance (response) was studied in detail. Design of Experiment (DOE) analysis showed the “optimized formulation” of the blend. Increase in PPE‐polystyrene (PS) content increased tensile strength and modulus of the blend, followed by a decrease in strain at break. However, EVA had a reverse effect on tensile strength and modulus. Strain at break increased significantly with increasing SEBS content in the blend. Graphical and numerical optimization showed that superior mechanical properties (tensile strength, strain at break and modulus) could be achieved at VA content ~ 50% at a particular loading of EVA. Low MW SEBS was found to be more compatible with the other components of the blend. Mechanical properties of the quaternary blend were marginally affected with change in IV of PPE in the range of 0.33 to 0.46. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
105.
Lipid carriers for delivery of celecoxib: In vitro,in vivo assessment of nanomedicine in rheumatoid arthritis
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106.
Khan Muhammad Umer Arif Shukla Sanjay Kumar Raja Muhammad Nouman Amjad 《Neural computing & applications》2021,33(21):14861-14885
Neural Computing and Applications - Marston’s load theory is commonly used for understanding the soil–conduit interaction. However, there are no practical methods available which can... 相似文献
107.
Wireless Personal Communications - Everyone today actively uses online social networks to get in touch with their friends, for career opportunities, and business also. Some of the most popular... 相似文献
108.
The oxide films formed during early stage of oxidation at 800 °C on dendritic and interdendritic regions of the cast Fe–16Al–1C (wt.%) alloy were studied using scanning Auger electron spectroscopy. Microhardness measurement and elemental depth profiles by Auger spectroscopy reveal that the carbide, Fe3AlC0.69, is the major constituent of the interdendritic region, while dendrites are predominantly Fe3Al phase. Between the two, the interdendritic region is found to be more prone to oxidation than the dendritic region, which was attributed to presence of carbides with low-Al content. In spite of the difference in oxide film thickness exhibited by both the phases, they consist of an inner aluminium oxide layer and an outer iron oxide layer. 相似文献
109.
110.
This paper presents a study of responsivity of InAs0·3Sb0·7 infrared detector. Thin films of InAs0·3Sb0·7 semiconducting compound were prepared by vacuum evaporation on glass and mica substrates held at 473° K under a pressure
of 10−6 torr with deposition rate of 20 A°/sec. The isothermal annealing process was employed to improve the quality of the films.
The responsivity variation with blackbody temperature (333° K to 673° K), detector temperature (80° K to 303° K) and frequency
(10 Hz to 10 kHz) was measured. The experimental set-up and the results are presented and discussed. 相似文献