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11.
Ceria-supported Au catalyst has been synthesized by the solution combustion method for the first time and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Au is dispersed as Au0 as well as Au3+ states on CeO2 surface of 20-30 nm crystallites. On heating the as-prepared 1% Au/CeO2 in air, the concentration of Au3+ ions on CeO2 increases at the expense of Au0. Catalytic activities for CO and hydrocarbon oxidation and NO reduction over the as-prepared and the heat-treated 1% Au/CeO2 have been carried out using a temperature-programmed reaction technique in a packed bed tubular reactor. The results are compared with nano-sized Au metal particles dispersed on -Al2O2 substrate prepared by the same method. All the reactions over heat-treated Au/CeO2 occur at lower temperature in comparison with the as-prepared Au/CeO2 and Au/Al2O2. The rate of NO + CO reaction over as-prepared and heat-treated 1% Au/CeO2 are 28.3 and 54.0 mol g-1 s-1 at 250 and 300 °C respectively. Activation energy (E
a) values are 106 and 90 kJ mol-1 for CO + O2 reaction respectively over as-prepared and heat-treated 1% Au/CeO2 respectively. 相似文献
12.
Indrajit Banerjee Prasenjit ChanakAuthor VitaeHafizur RahamanAuthor Vitae Tuhina SamantaAuthor Vitae 《Computers & Electrical Engineering》2014
In a wireless sensor network (WSN), random occurrences of faulty nodes degrade the quality of service of the network. In this paper, we propose an efficient fault detection and routing (EFDR) scheme to manage a large size WSN. The faulty nodes are detected by neighbour node’s temporal and spatial correlation of sensing information and heart beat message passed by the cluster head. In EFDR scheme, three linear cellular automata (CA) are used to manage transmitter circuit/ battery condition/microcontroller fault, receiver circuit fault and sensor circuit fault representation. On the other hand, L-system rules based data routing scheme is proposed to determine optimal routing path between cluster head and base station. The proposed EFDR technique is capable of detecting and managing the faulty nodes in an efficient manner. The simulation results show 86% improvement in the rate of energy loss compared to an existing algorithm. 相似文献
13.
Betal Atanu Bera Jayanta Alam Mahfooz Gandi Appala Naidu Sahu Satyajit 《Journal of Computational Electronics》2022,21(1):227-234
Journal of Computational Electronics - The strain- and electric field-dependent electronic and optical properties of monolayer GaInS2 have been calculated using density functional... 相似文献
14.
Microstructure and mechanical properties of friction stir welded oxide dispersion strengthened alloy
Jiye Wang Wei Yuan Rajiv S. Mishra Indrajit Charit 《Journal of Nuclear Materials》2013,432(1-3):274-280
Effect of friction stir welding (FSW) on microstructure and mechanical properties of oxide dispersion strengthened alloy MA956 was investigated. Fine grained microstructure was developed in the processed region with slight particle coarsening. Tensile behavior of the processed material was compared with that of the as-received material at room temperature. Results indicated that significant grain refinement during FSW compensated for the reduced particle strengthening contribution and enhanced tensile strength by 145 MPa without loss in ductility. Further analysis indicated a good agreement between experimentally measured yield strength and the strength calculated by Pythagorean superimposition of strengthening contribution in FSWed material. 相似文献
15.
An adaptive penalty function-based maximin desirability index for close tolerance multiple-response optimization problems 总被引:1,自引:0,他引:1
Sasadhar Bera Indrajit Mukherjee 《The International Journal of Advanced Manufacturing Technology》2012,61(1-4):379-390
Simultaneous optimization of multiple-quality characteristics and determining the process settings is a critical and difficult task for practitioners. Such types of problems are generally referred to as “multiple-response optimization” problems. To handle high-dimensional multiple-response problems, a popular strategy, using desirability functions, is recommended by various researchers. Various types of desirability index functions are recommended to convert multiple scale-free desirability measures to a single composite desirability (or single objective) value. Thus, the objective is then to maximize the single composite desirability for a specific problem. In this paper, a new adaptive penalty function-based “maximin” desirability index is proposed, which provide superior solution as compared to existing maximin approach, for close (or tight) engineering tolerances of response characteristics. The superiority was proved based on statistical comparison using varied case situations and different swarm intelligent search strategies. 相似文献
16.
Artificial Photosynthesis: Ni‐Nanocluster Modified Black TiO2 with Dual Active Sites for Selective Photocatalytic CO2 Reduction (Small 2/2018)
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Sultan Alsagabi Indrajit Charit Somayeh Pasebani 《Journal of Materials Engineering and Performance》2016,25(2):401-408
Grade 92 steel (9Cr-2W) is a ferritic-martensitic steel with good mechanical and thermal properties. It is being considered for structural applications in Generation IV reactors. Still, the irradiation performance of this alloy needs more investigation as a result of the limited available data. The irradiation performance investigation of Grade 92 steel would contribute to the understanding of engineering aspects including feasibility of application, economy, and maintenance. In this study, Grade 92 steel was irradiated by iron ion beam to 10, 50, and 100 dpa at 30 and 500 °C. In general, the samples exhibited good radiation damage resistance at these testing parameters. The radiation-induced hardening was higher at 30 °C with higher dislocation density; however, the dislocation density was less pronounced at higher temperature. Moreover, the irradiated samples at 30 °C had defect clusters and their density increased at higher doses. On the other hand, dislocation loops were found in the irradiated sample at 50 dpa and 500 °C. Further, the irradiated samples did not show any bubble or void. 相似文献
20.
Present study highlights the development of carbon-loaded SBA 15 membrane on clay-alumina tubular support and its performance on the CO2 separation efficiencies from different mixture gases. To modify the large pores of SBA 15 by graphitic carbon, low molecular weight phenol–formaldehyde (PF) resin was incorporated into the mesoporous channel followed by calcination under inert atmosphere. The modified ordered pore structure of the membrane has been characterized by low-angle XRD, TEM, and pore size distribution analysis. The chemical state of the deposited carbon phase into the SBA 15 pores was analyzed by X-ray photoelectron and Raman spectroscopy. Carbon having graphitic nature mainly in graphene oxide has been deposited into the mesopore of SBA 15 resulting decrease in pore size from 8.9 to 1.0 nm. Finally, the developed SBA 15 carbon membranes were characterized by CO2 permeation and separation selectivity of CO2/CH4, CO2/CO. Highest CO2/CH4 separation factor was achieved as 16.9 with CO2 permeance 13.6 × 10–8 mol/m2/s/Pa at 200 kPa feed pressure by the 20% resin with 2 times coated membrane. In flue gas analysis, highest CO2/CO separation factor of 32.8 was achieved. This study offers an observation on CO2 separation from simulated BF gas for the first time and the results show the potential of the developed SBA 15/C composite membranes in commercial application. 相似文献