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111.
Rovee-Collier Carolyn; Bhatt Ramesh S.; Chazin Sharon 《Canadian Metallurgical Quarterly》1996,22(5):1178
The effects of set size and novelty on visual pop-out in 6-month-old infants was assessed in a perceptual-identification (memory reactivation) paradigm in which infants, trained and tested in their own homes, viewed a mobile containing a unique novel or familiar object amidst different numbers of familiar or novel distractors, respectively. Unique objects of both types popped out at all set sizes except the largest, where there was modest evidence that familiar distractors speeded processing (Experiment 1). When the proportion of familiar targets in a display of intermediate set size was increased, however, infants no longer detected the familiar target (Experiment 2). These findings offer additional support for the proposition that visual pop-out in infants and adults is the same phenomenon. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
112.
R. Pandiselvam S. Subhashini E.P. Banuu Priya Anjineyulu Kothakota S.V. Ramesh S. Shahir 《臭氧:科学与工程》2019,41(1):17-34
Extending shelf life of food products is a major concern of the producers, and the food industry requires ‘greener’ alternatives to the current technologies. Ozone-based food preservation may suit this niche. Ozone is an attractive alternative preservative that food industry needs due to its properties such as quick decomposition and little residual effect during food preservation. Ozone is the strongest molecule available for the disinfection of water and is second only to elemental fluorine in oxidizing power. Ozone is being used in the food industry in various applications such as decontamination of water and equipment surfaces. Several researchers have focused on the application of ozone to inactivate microorganisms on fresh produce, like fruits, vegetables, meat, poultry, fish, and eggs, and dry produce, such as cereals, pulses, and spices. This review comprehensively analyses appropriate ozone concentrations and exposure times and discusses various factors that affect the quality and safety of food products during ozonation. 相似文献
113.
Ramesh Borade Oliver Bruemmer Anil Guram Howard Turner Xiao Wang 《Chemical Engineering Communications》2013,200(12):1621-1635
High-throughput synthesis and screening of libraries consisting of redox zeolites and molecular sieves have been developed for the selective oxidation of 2-butyl-5-hydroxymethyl-imidazole to the corresponding aldehyde in the liquid phase. Libraries consisting of 96 catalysts were prepared and screened for catalytic activity using high-throughput software, robotics, reactor, and screening technologies. The integrated synthesis and screening workflow allowed ~5000 samples to be screened in less than one month. Promising hits identified in the high-throughput primary screens were successfully scaled up and optimized in conventional laboratory test units. Best results have been obtained with doubly or triply doped mesoporous sieves containing both an impregnated and framework-substituted metal. PtBi-doped framework-substituted V-MCM-41 redox mesoporous sieves were found to be efficient catalysts for aerobic oxidation under relatively mild reaction conditions (100–150°C, 15–400 psi air, 4–10 h reaction time). MIBK/H2O/t-BuOH mixtures were identified as efficient solvent systems for this reaction. Isolated yields confirm high selectivities of more than 90% with quantitative conversions. Spent catalysts were shown to be fully regenerable by high temperature calcination in air. 相似文献
114.
This paper reported on the work performed to study the formation of silicon nitride and silicon carbide whiskers using the carbothermal nitridation process. A distinctive aspect of the present study lies in the use of the mechanical milling method to alter the regularity of the crystalline network of the silica sand. In order to optimise the processing parameters for the synthesis of silicon carbide, the concept of Taguchi's Design of Experiments was considered, the analysis being based on Taguchi's signal to noise ratio and variance techniques to obtain optimum combination of process parameters. Important factors influencing the formation of silicon carbide were the duration of the mechanical milling, followed by temperature, time and heating rate. 相似文献
115.
A novel active auxiliary circuit for efficiency enhancement integrated with synchronous buck converter 下载免费PDF全文
Anup Kumar Panda Shiva Sarode Ramesh Tejavathu 《International Journal of Circuit Theory and Applications》2016,44(12):2043-2057
In this paper, a novel auxiliary circuit is introduced for the synchronous buck converter. This auxiliary circuit provides zero‐current, zero‐voltage switching conditions for the main and synchronous switches while providing zero‐current condition for the auxiliary switch and diodes. The proposed active auxiliary circuit integrated with synchronous buck converter that emanates to zero‐voltage transition (ZVT)–zero‐current transition (ZCT) pulse width‐modulated (PWM) synchronous buck converter is analyzed, and its operating modes are presented. The additional voltage and current stresses on main, synchronous and auxiliary switches get decimated because of the resonance of the auxiliary circuit that acts for a small segment of time in the proposed converter. The important design feature of soft‐switching converters is the placement of resonant components that mollifies the switching and conduction losses. With the advent of ZVT–ZCT switching, there is an increase in the switching frequency that declines the resonant component values in the converters and also constricts the switching losses. The characteristics of the proposed converter are verified with the simulation in the Power Sim (PSIM) software co‐simulated with MATLAB/SIMULINK environment and implemented experimentally. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
116.
In this work, the potential benefit of tri-metal gate engineered nanowire MOSFET with gate stack for analog/RF applications is developed and presented. A systematic, quantitative investigation of main figure of merit for the device is carried out to demonstrate its improved RF/analog performance. The results show an improvement in drain current, \(I_{\mathrm{on}} /I_{\mathrm{off}}\) ratio, transconductance, unity-gain frequency (\(f_{\mathrm{T}}\)), maximum oscillation frequency (\(f_{\mathrm{max}}\)) providing superior RF performance as compared to single and dual-metal gate stack nanowire MOSFET. The suitability of the device for analog/RF applications is also analyzed by implementing the device in a low-noise amplifier circuit, and the S-parameter values are estimated. 相似文献
117.
Mallikarjuna A. Kumar N. Suresh Babu T. Anil Ramesh S. Naidu K. Chandra Babu 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(12):4512-4522
Journal of Inorganic and Organometallic Polymers and Materials - (1-x) (Al0.2La0.8TiO3)?+?(x) (BiZnFeO3) (x?=?0.2–0.8) [ALTBZFO] nanocomposites were synthesized via... 相似文献
118.
119.
Marjan Safarzadeh S. Ramesh C.Y. Tan Hari Chandran Ahmad Fauzi Mohd Noor S. Krishnasamy U. Johnson Alengaram S. Ramesh 《Ceramics International》2019,45(3):3473-3477
The effect of multi-ions (Mg2+, SiO44-, Zn2+, Cu2+) doping on the properties of carbonated hydroxyapatite (CHA) prepared by a wet chemical method has been investigated. Different combinations of ions were doped into the CHA and the as-synthesized compacts were sintered at 900?°C prior to body characterization. It was found that regardless of ions doping, the lattice structure of the CHA was not disrupted. In addition, secondary phases were not detected for all the multi-ions doped samples. The XRD and FTIR results further confirmed the presences of a B-Type CHA in the sintered samples. The XRD analysis revealed that the lattice parameters (c/a ratio) increased with dopant addition and resulted in a smaller crystallite size. The FESEM examination also showed the presences of smaller grain size for the multi-ions doped CHA samples thus indicating that the doping was beneficial in suppressing grain coarsening in carbonated hydroxyapatite. 相似文献
120.
Chinnathaypgal Veeresh Nayak Rangarasaiah Ramesh Motagondanahalli Desai Vijay Samanta Sudip Kumar 《SILICON》2019,11(1):175-185
Silicon - Metal injection moulding (MIM) is a near-net shape manufacturing technology for producing intricate parts, cost-effectively. MIM comprises combined techniques of plastic injection... 相似文献