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91.
92.
Pramod Chaitanya Ritu Mishra Pradeep Kumar Ahirwal O. P. Thakur Lakshman Pandey 《Integrated ferroelectrics》2015,159(1):121-126
The electrical behavior of strontium titanate borosilicate glass ceramics (SrO.TiO2- 2SiO2.B2O3) with additives K2O, La2O3, CoO and Nb2O5 was studied by using Impedance Spectroscopy as a function of temperature and composition. An equivalent circuit model having three parallel RC's connected in series with a capacitor C4 could represent the data well. By comparing the complex modulus plots with simulated ones and looking at the values of the time constants these RC's were attributed to represent crystalline, glassy and glass-crystal interface regions of the glass- ceramic whereas C4 represented the glass-ceramic sample and contact electrode interface. When the glass ceramic sample contained only SrTiO3 crystalline phase and the remaining glassy matrix, the interface capacitance showed an Arrhenius type of nature with an activation energy (0.11 ± 0.04) eV and when the glass- ceramic sample contained number of crystalline phases no clear cut trend appeared. These findings are useful in selecting suitable electrodes for applications as well as in deciding upon experimental techniques for measurement of dielectric constants of materials. 相似文献
93.
A substantial improvement in the thermal performance of solar air heater is found by using roughness on the underside of the absorber plate. In the present investigation, the effect of relative roughness height of roughness element on the thermohydraulic performance of solar air heaters is carried out. The range of roughness and flow parameters for the investigation are relative roughness height (e/H): 0.285–0.6, relative roughness pitch (P/e): 2, angle of attack (α): 60°, open area ratio (β): 12% and Reynolds number (Re): 3800–19,000. The relative roughness height of 0.285 is thermohydraulically better in comparison to other relative roughness heights. The results show that the V down perforated baffles is thermohydraulically better than the solid baffles. 相似文献
94.
95.
Devi Neena Patel Sanjay K. S. Kumar Pradeep Singh Archana Thakur Nandita Lata Jeevan Pandey Deepak Thakur Vikram Chand Duni 《Catalysis Letters》2022,152(4):944-953
Catalysis Letters - In this study, Rhodococcus pyridinivorans cells containing hyperactive acyltransferase was immobilized on various macromolecules based-polymeric matrices and used to improve... 相似文献
96.
Investigation and optimization of lubrication parameters in high speed turning of superalloy Inconel 718 总被引:2,自引:2,他引:0
Dinesh G. Thakur B. Ramamoorthy L. Vijayaraghavan 《The International Journal of Advanced Manufacturing Technology》2010,50(5-8):471-478
Dry machining is sometimes less effective when higher machining efficiency, better surface finish quality, and severe cutting conditions are required. For these situations, semi-dry operations utilizing very small amount of cutting fluids called minimum quantity lubrication is expected to become a powerful tool and played a significant role in a number of practical applications. It has been observed from the literature survey that a systematic research work has to be carried out to determine the optimum quantity of lubricant with appropriate cutting conditions for achieving better machinability characteristics of a material. Hence, an attempt has been made in this paper to enhance the machinability characteristics in high speed turning of superalloy Inconel 718 using quantity of lubricant, delivery pressure at the nozzle, frequency of pulses, direction of application of cutting fluid, cutting speed, and feed rate as the process parameters. Results indicated that the use of optimized minimum quantity lubrication parameters under pulsed jet mode leads to lower cutting force, cutting temperature, and flank wear. 相似文献
97.
Identification of interaction patterns in complex networks via community structures has gathered a lot of attention in recent research studies. Local community structures provide a better measure to understand and visualise the nature of interaction when the global knowledge of networks is unknown. Recent research on local community structures, however, lacks the feature to adjust itself in the dynamic networks and heavily depends on the source vertex position. In this study the authors propose a novel approach to identify local communities based on iterative agglomeration and local optimisation. The proposed solution has two significant improvements: (i) in each iteration, agglomeration strengthens the local community measure by selecting the best possible set of vertices, and (ii) the proposed vertex and community rank criterion are suitable for the dynamic networks where the interactions among vertices may change over time. In order to evaluate the proposed algorithm, extensive experiments and benchmarking on computer generated networks as well as real-world social and biological networks have been conducted. The experiment results reflect that the proposed algorithm can identify local communities, irrespective of the source vertex position, with more than 92% accuracy in the synthetic as well as in the real-world networks. 相似文献
98.
JAROSLAV KAŠPAR IGOR KOROPECKÝ EDUARD BRYNDA STANISLAV NEŠPUdotREK 《International Journal of Electronics》2013,100(5):1041-1042
Langmuir-Blodgett films have been prepared from copper tetra-4-t-butylphthalocyanine. A voltage dependence of capacitance can be attributed to the presence of a Schottky depletion layer. The barrier potential was determined as l·4eV, and the carrier concentration about 1024m?3 相似文献
99.
100.
Simultaneous sequestration of nitrate and phosphate from wastewater using a tailor‐made bacterial consortium in biofilm bioreactor 下载免费PDF全文
Pallavi Mukherjee Chaitali Chanda Moumita Bhaumik Madhurima Ghosh Jaweria Sharmin Poulami Datta Srimoyee Banerjee Parthasarathi Barat Ashoke Ranjan Thakur Lalit Mohan Gantayet Indranil Mukherjee Shaon Ray Chaudhuri 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2018,93(5):1279-1289