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951.
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   
952.
Anusuya  P  Kumar  Prashanth  Esakki  Papanasam  Agarwal  Lucky 《SILICON》2022,14(16):10187-10198
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   
953.
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   
954.
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   
955.
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   
956.
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   
957.
958.
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   
959.
This study demonstrates a cost‐effective way to fabricate porous ceramics with tailored porosity and pore microstructure using 5–40 wt% rice husk (RH) in <75 μm, 75–180 μm, 180–355 μm, 355–420 μm, and 420–600 μm size, as pore former. Sucrose, used as binder, also acted as a pore former. Porous alumina compacts with 20%–66% volume fraction porosity and 50–516 μm pore size (length) were successfully fabricated. Microstructure of samples reveal randomly oriented elongated coarse pores and fine pores (avg. size 4 μm), created during burnout of RH and sucrose, respectively. Samples with isolated and/or interconnected pores were fabricated using this process. Thermal conductivity of the samples prepared was measured using Transient Plane Source (TPS) technique. Thermal conductivity ranges from 1.2 to 24 W/mK. Experimental results agree closely with predictions made based on Effective Medium Theory (EMT) for a two‐phase system.  相似文献   
960.
The potential of poly(ethyleneterephthalate) glycolysates toward improving the energy absorption characteristics of cycloaliphatic epoxy resins has been explored. Microwave‐assisted glycolytic depolymerization of PET was performed in the presence of polyether diols of different molecular weights. The obtained glycolysates were blended with epoxy, and their mechanical properties were studied under both quasi‐static and dynamic conditions. Significant improvements were observed, which were found to depend both on the amount as well as nature of glycolysate. Amine functionalities were introduced at the terminal positions of glycolysates to improve the compatibility between the two phases. The amine derivatives exhibited superior performance and the Mode I fracture toughness (KIC) of epoxy increased by ~18% in optimized compositions, which is indicative of its improved notch sensitivity. Neat epoxy specimens fractured in a brittle fashion, but all the blends exhibited ductile failure, as evidenced by surface morphological investigations. The mechanical properties of epoxy blends prepared with analogous aliphatic polyols, both before and after amine functionalization, were also studied which clearly reveal the beneficial role of aromatic groups toward improving the toughness of the base cycloaliphatic epoxy resin without compromising on the material stiffness. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39941.  相似文献   
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