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101.
Moni Kanchan Datta Jeffrey Maranchi Sung Jae Chung Rigved Epur Karan Kadakia Prashanth Jampani Prashant N. Kumta 《Electrochimica acta》2011,(13):4717
The buffering effect of carbon on the structural stability of amorphous silicon films, used as an anode for lithium ion rechargeable batteries, has been studied during long term discharge/charge cycles. To this extent, the electrochemical performance of a prototype material consisting of amorphous Si thin film (∼250 nm) deposited by radio frequency magnetron sputtering on amorphous carbon (∼50 nm) thin films, denoted as a-C/Si, has been investigated. In comparison to pure amorphous Si thin film (a-Si) which shows a rapid fade in capacity after 30 cycles, the a-C/Si exhibits excellent capacity retention displaying ∼0.03% fade in capacity up to 50 cycles and ∼0.2% after 50 cycles when cycled at a rate of 100 μA/cm2 (∼C/2) suggesting that the presence of thin amorphous C layer deposited between the Cu substrate and a-Si acts as a buffer layer facilitating the release of the volume induced stresses exhibited by pure a-Si during the charge/discharge cycles. This structural integrity combined with microstructural stability of the a-C/Si thin film during the alloying/dealloying process with lithium has been confirmed by scanning electron microscopy (SEM) analysis. The buffering capacity of the thin amorphous carbon layer lends credence to its use as the likely compliant matrix to curtail the volume expansion related cracking of silicon validating its choice as the matrix for bulk and thin film battery systems. 相似文献
102.
G. Selvarani S.K. Prashant A.K. Sahu P. Sridhar S. Pitchumani A.K. Shukla 《Journal of power sources》2008
A direct borohydride-hydrogen peroxide fuel cell employing carbon-supported Prussian Blue (PB) as mediated electron-transfer cathode catalyst is reported. While operating at 30 °C, the direct borohydride-hydrogen peroxide fuel cell employing carbon-supported PB cathode catalyst shows superior performance with the maximum output power density of 68 mW cm−2 at an operating voltage of 1.1 V compared to direct borohydride-hydrogen peroxide fuel cell employing the conventional gold-based cathode with the maximum output power density of 47 mW cm−2 at an operating voltage of 0.7 V. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Analysis (EDAX) suggest that anchoring of Cetyl-Trimethyl Ammonium Bromide (CTAB) as a surfactant moiety on carbon-supported PB affects the catalyst morphology. Polarization studies on direct borohydride-hydrogen peroxide fuel cell with carbon-supported CTAB-anchored PB cathode exhibit better performance with the maximum output power density of 50 mW cm−2 at an operating voltage of 1 V than the direct borohydride-hydrogen peroxide fuel cell with carbon-supported Prussian Blue without CTAB with the maximum output power density of 29 mW cm−2 at an operating voltage of 1 V. 相似文献
103.
Effect of working gap and circumferential speed on the performance of magnetic abrasive finishing process 总被引:2,自引:0,他引:2
Magnetic abrasive finishing (MAF) is one of the advanced finishing processes in which workpiece is kept between two magnets, and cutting force is controlled by working gap and magnetic field between the two magnets. MAF setup is designed for finishing cylindrical workpieces and it is mounted on lathe machine. The loosely bounded powder is prepared for experimentation by homogeneous mixing of magnetic powder (Fe powder of 300 mesh size (51.4 μm)), abrasive powder (Al2O3 of 600 mesh size (25.7 μm), and lubricant called servospin-12 oil. To investigate the effects of working gap and circumferential speed on material removal, change in surface finish and percent improvement in surface finish, a series of experiments have been conducted using in-house fabricated setup. Based upon the results, in general, material removal decreases by increasing working gap or decreasing circumferential speed of the workpiece. Change in surface finish increases by increasing circumferential speed of the workpiece. 相似文献
104.
Application of Petri Nets and a Genetic Algorithm to Multi-Mode Multi-Resource Constrained Project Scheduling 总被引:2,自引:0,他引:2
J. Prashant Reddy S. Kumanan O.V. Krishnaiah Chetty 《The International Journal of Advanced Manufacturing Technology》2001,17(4):305-314
Multi-mode and multi-resource constrained scheduling of a project is a complex task. This paper addresses the use of a Petri
net as a modelling and scheduling tool in this context. The benefits of Petri nets in project scheduling are discussed. We
propose extensions to Petri nets to suit scheduling of activities in a decision CPM. We also propose the use of a P-matrix
for token movements in Petri nets. A genetic algorithm is used to find a better solution. Petri-net-aided software including
genetic-algorithm-based search and heuristics is described to deal with a multi-mode, multi-constrained scheduling problem
with pre-emption of activities. 相似文献
105.
Minh Tam Hoang Amandeep Singh Pannu Yang Yang Sepideh Madani Paul Shaw Prashant Sonar Tuquabo Tesfamichael Hongxia Wang 《纳微快报(英文)》2022,(4):277-288
The remarkable evolution of metal halide perovskites in the past dec-ade makes them promise for next-generation optoelectronic material.In particular,nanocrysta... 相似文献
106.
The effect of rubber hardness on the properties of fiber‐reinforced plastic (FRP) composites is investigated in order to know the optimum composition of rubber mold used in rubber pressure molding (RPM) technique. A matching die set was used in RPM method, where the die was made of hard metal like steel and the punch from the flexible rubber like material, natural rubber. The use of flexible rubber punch generates and applies hydrostatic pressure on the surface of FRP composites. The hardness of rubber mold was controlled by incorporating carbon black as a filler material in the matrix of natural rubber and varied from 0 to 75 phr (per hundred rubber) in steps of 15 phr. Burn test, tension test, interlaminar shear test and interlaminar fracture toughness tests were conducted on the FRP composites to measure the void content, presence of delamination, tensile strength, inter laminar shear strength and inter laminar fracture toughness. The results are compared with the FRP composites made by conventional technique to evaluate the performance of RPM technique. It is observed that the laminates produced by RPM technique with different filler content in natural rubber mold show significant improvement in mechanical properties except interlaminar shear strength. POLYM. COMPOS., 28:618–630, 2007. © 2007 Society of Plastics Engineers 相似文献
107.
Thermal history of droplets associated with gas atomization of melt has been investigated. A mathematical model, based on
classical theory of heterogeneous nucleation and volume separation of nucleants among droplets size distribution, is described
to predict undercooling of droplets. Newtonian heat flow condition coupled with velocity dependent heat transfer coefficient
is used to obtain cooling rate before and after nucleation of droplets. The results indicate that temperature profile of droplets
in the spray during recalescence, segregated and eutectic solidification regimes is dependent on their size and related undercooling.
The interface temperature during solidification of undercooled droplets rapidly approaches the liquidus temperature of the
alloy with a subsequent decrease in solid-liquid interface velocity. A comparison in cooling rates of atomized powder particles
estimated from secondary dendrite arm spacing measurements are observed to be closer to those predicted from the model during
segregated solidification regime of large size droplets. 相似文献
108.
Sharma Rachit Kumar Singh Prashant Kumar Sarkar Prabir Singh Harpreet 《Clean Technologies and Environmental Policy》2020,22(9):1871-1889
Clean Technologies and Environmental Policy - Companies are under increasing pressure to inculcate sustainability in their supply chain networks. However, the companies face significant amount of... 相似文献
109.
Hadi Shahnazari Prashant Mhaskar John M. House Timothy I. Salsbury 《American Institute of Chemical Engineers》2019,65(2):640-651
The problem of distributed fault detection and isolation (FDI) for heating, ventilation, and air conditioning (HVAC) systems has been addressed in this work. First, a linear model is identified for subunits of an HVAC system. Next, a local FDI (LFDI) framework is designed for each unit under consideration. A distributed FDI architecture is designed where the LFDI frameworks communicate to exchange information to achieve enhanced FDI in each unit. As a result, each LFDI framework functions as intended even in the presence of faults that affect multiple units. Effectiveness of the proposed distributed FDI framework is shown for various commonly occurring fault scenarios. © 2018 American Institute of Chemical Engineers AIChE J, 65: 640–651, 2019 相似文献
110.
In this article, an experimental comparison between open sun and solar drying is done. The thermal performance of evacuated tube based solar dryer is investigated with drying characteristics of Phyllanthus Emblica (Anvla), Aloe Vera, Aegle Marmelos (Bel) and leaves of Azadirachta Indica (Neem), Aegle Marmelos (Bel) and Psidium Guajava (Guava). In this setup, an evacuated tube collector, shell and tube heat exchanger and drying chamber are used. It was found that the maximum temperature difference between hot air and ambient air is 35.4°C and maximum efficiency of the setup is calculated as 55%. The average drying rate of Phyllanthus Emblica (Anvla), Aloe Vera and Aegle Marmelos (Bel) is measured as 0.46?g/min, 0.44?g/min, and 0.39?g/min respectively which are higher than that of Open Sun Drying. The leaves of Azadirachta Indica (Neem), Aegle Marmelos (Bel) and Psidium Guajava (Guava) also get dried with faster rates of 0.18?g/min, 0.17?g/min, and 0.14?g/min respectively. 相似文献