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991.
Silicon - Advances in microelectronics have enabled smaller technical nodes, lower threshold voltages, and greater working frequencies. Even though VLSI circuit performance and power consumption... 相似文献
992.
Chugh Nisha Kumar Manoj Haldar Subhasis Bhattacharya Monika Gupta R.S. 《SILICON》2022,14(3):1029-1038
Silicon - In the present communication, for the first time, applicability of Field Plate (FP) for Double Channel (DC) AlGaN/GaNHEMT is demonstrated. Impact of design space parameters such as field... 相似文献
993.
Kumar Siddharth Yian Wang Jing Wang Fei Xiao Gabriel Sikukuu Nambafu Usman Bin Shahid Fei Yang Ernest Pahuyo Delmo Minhua Shao 《Frontiers of Chemical Science and Engineering》2022,16(6):930
Ammonia electrooxidation reaction involving multistep electron-proton transfer is a significant reaction for fuel cells, hydrogen production and understanding nitrogen cycle. Platinum has been established as the best electrocatalyst for ammonia oxidation in aqueous alkaline media. In this study, Pt/nitrogen-doped graphene (NDG) and Pt/tungsten monocarbide (WC)/NDG are synthesized by a wet chemistry method and their ammonia oxidation activities are compared to commercial Pt/C. Pt/NDG exhibits a specific activity of 0.472 mA∙cm–2, which is 44% higher than commercial Pt/C, thus establishing NDG as a more effective support than carbon black. Moreover, it is demonstrated that WC as a support also impacts the activity with further 30% increase in comparison to NDG. Surface modification with Ir resulted in the best electrocatalytic activity with Pt-Ir/WC/NDG having almost thrice the current density of commercial Pt/C. This work adds insights regarding the role of NDG and WC as efficient supports along with significant impact of Ir surface modification. 相似文献
994.
Kumar T. Rajesh Shanmugan S. Sundari G. Sunita Devi N. S. M. P Latha Abhiram N. Palanikumar G. 《SILICON》2022,14(7):3501-3514
Silicon - Now, enticing systematic civic since everywhere the world is used in green synthesis and benefit of the simple is eco-friendly with an emergent method of producing nanoparticles (NPs).... 相似文献
995.
Silicon - In this review, we discussed highly sensitive biosensor devices which is having a more attractive, wide scope and development in the sensing field. Biosensor devices can detect the... 相似文献
996.
Powder Metallurgy and Metal Ceramics - Powder compaction is the most crucial process in powder metallurgy since almost all the desired properties of a material, such as a shape, size, density,... 相似文献
997.
Senthil Kumar Raman Heuy Dong Kim 《Journal of Mechanical Science and Technology》2018,32(3):1099-1104
The accuracy of the thermodynamic properties prediction from the different Equation of state (EOS) varies upon the range of temperature and pressure. Despite the variety of EOS available, there is no de facto for selecting an EOS for particular computational modeling. The EOS model recently developed by Kumar and Kim (K-K EOS) determines more accurately the thermodynamic properties of CO2 than earlier models. In this present study, K-K EOS is successfully implemented in the computational analysis of compressible supercritical CO2 flow (S-CO2) in the thermodynamic region near and away from the vapour-liquid critical point. Computational results of SCO2 flow with the real gas properties predicted with the K-K EOS is compared with Span and Wagner (SW EOS) and ideal EOS. 相似文献
998.
Kumar Rajneesh Goel Varun Kumar Anoop Khurana Sourabh Singh Paramvir Bopche Santosh B. 《Journal of Mechanical Science and Technology》2018,32(1):399-404
Journal of Mechanical Science and Technology - The Computational fluid dynamics (CFD) based analysis is carried out to investigate the thermal and hydraulic performance of circular rib roughened... 相似文献
999.
Oil-in-water emulsions are used as metalworking fluids (MWFs). Considering the environmental issues and operator's health, the amount of oil-in-MWFs is one of the important parameters. In the present study, paraffin oil is used for emulsion formulation and possibilities to minimize the amount of paraffin oil-in-MWFs are explored. Physical characterization of emulsions is done using dynamic light scattering and goniometer. The tribological response of emulsions is recorded using the Four-ball tester. Results indicate that the amount of oil can be brought down to a level of 0.5% v/v to achieve the standard friction level. Droplet size and distribution seems to control the lubricity of emulsions, smaller droplets are desired for better lubrication. 相似文献
1000.
Sisira Kanta Pattnaik Neeraj Kumar Bhoi Sachidananda Padhi Saroj Kumar Sarangi 《The International Journal of Advanced Manufacturing Technology》2018,98(1-4):55-65
Machining of aluminum and its alloy is very difficult due to the adhesion and diffusion of aluminum, thus the formation of built-up edge (BUE) on the surface. The BUE, which affects the surface integrity and tool life significantly, affects the service and performance of the workpiece. The minimization of BUE was carried out by selection of proper cutting speed, feed, depth of cut, and cutting tool material. This paper presents machining of rolled aluminum at cutting speeds of 336, 426, and 540 m/min, the feeds of 0.045, 0.06, and 0.09 mm/rev, and a constant depth of cut of 0.2 mm in dry condition. Five cutting tools WC SPUN grade, WC SPGN grade, WC + PVD (physical vapor deposition) TiN coating, WC + Ti (C, N) + Al2O3 PVD multilayer coatings, and PCD (polycrystalline diamond) were utilized for the experiments. The surface roughness produced, total flank wear, and cut chip thicknesses were measured. The characterization of the tool was carried out by a scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) pattern. The chip underface was analyzed for the study of chip deformation produced after machining. The results indicated that the PCD tool provides better results in terms of roughness, tool wear, and smoother chip underface. It provides promising results in all aspects. 相似文献