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排序方式: 共有1484条查询结果,搜索用时 15 毫秒
1.
Manoj Karakoti Ritu Jangra Sandeep Pandey Pawan Singh Dhapola Sunil Dhali Suman Mahendia Pramod K Singh Nanda Gopal Sahoo 《International Journal of Applied Ceramic Technology》2020,17(4):1899-1908
This study deals with the utility of mini spray dryer process to improve the dispersibility, of graphene oxide(GO) and its application for high-performance supercapacitor. Initially, the neutral solution of GO was obtained using the modified Hummer's method. After this, the prepared GO solution was processed by mini spray dryer to obtain a more purified, lighter, and dispersed form of GO which is named as spray dryer processed GO (SPGO). The SPGO thus obtained showed excellent dispersibility behavior with various solvents, which is not found in case of conventional oven drying. Furthermore, utility of SPGO and its reduced form (r-SPGO) for supercapacitor applications have been investigated. Results obtained from the cyclic voltammetry(CV) analysis, impedance, and charge-discharge behavior of supercapacitor fabricated using r-SPGO shows enhanced features. Therefore, the simple spray dried GO and its reduced form, that is, r-SPGO can be utilized as a potential candidate for the supercapacitor application. Herein, as synthesized SPGO exhibited the specific capacitance of 12.07 and 37.6 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively, at a scan rate of 5 mV/s. On the other hand, reduced form of SPGO, that is, r-SPGO showed the specific capacitance of 27.16 and 230 F/g with PVA-H3PO4 and 1 mol/L H3PO4, respectively. 相似文献
2.
Environmental concerns continue to pose the challenge to replace petroleum-based products with renewable ones completely or at least partially while maintaining comparable properties. Herein, rigid polyurethane (PU) foams were prepared using soy-based polyol for structural and thermal insulation applications. Cell size, density, thermal resistivity, and compression force deflection (CFD) values were evaluated and compared with that of petroleum-based PU foam Baydur 683. The roles of different additives, that is, catalyst, blowing agent, surfactants, and different functionalities of polyol on the properties of fabricated foam were also investigated. For this study, dibutyltin dilaurate was employed as catalyst and water as environment friendly blowing agent. Their competitive effect on density and cell size of the PU foams were evaluated. Five different silicone-based surfactants were employed to study the effect of surface tension on cell size of foam. It was also found that 5 g of surfactant per 100 g of polyol produced a foam with minimum surface tension and highest thermal resistivity (R value: 26.11 m2·K/W). However, CFD values were compromised for higher surfactant loading. Additionally, blending of 5 g of higher functionality soy-based polyol improved the CFD values to 328.19 kPa, which was comparable to that of petroleum-based foam Baydur 683. 相似文献
3.
Bioremediation by alkaline protease (AkP) from edible mushroom Termitomyces clypeatus: optimization approach based on statistical design and characterization for diverse applications
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Bose Bimal K. Szczesny Paul M. Steigerwald Robert L. 《Industry Applications, IEEE Transactions on》1985,(5):1182-1191
Microcomputer-based control of a residential photovoltaic power conditioning system is described. The microcomputer is responsible for array current feedback control, maximum power tracking control, array safe zone steering control, phase-locked reference wave synthesis, sequencing control, and some diagnostics. The control functions are implemented using Intel 8751 single-chip microcomputer-based hardware and software. The controller has been tested in the laboratory with the prototype power conditioner and shows excellent performance. 相似文献
6.
Zhiping Lin Xu L. Bose N.K. 《IEEE transactions on circuits and systems. I, Regular papers》2008,55(1):445-461
7.
Properties determining choice of mother wavelet 总被引:3,自引:0,他引:3
Ahuja N. Lertrattanapanich S. Bose N.K. 《Vision, Image and Signal Processing, IEE Proceedings -》2005,152(5):659-664
Properties of wavelets with finite as well as infinite support are summarised to facilitate mother wavelet selection in a chosen application. The quantitative guidelines reduce dependence on trial-and-error schemes resorted to for selection and underscore the importance of such selection in any application of interest. In wavelet-based image sequence superresolution, studied during the last four years, the use of a B-spline mother wavelet is justified. 相似文献
8.
Harish Chander V ShankerD Haranath Suman DudejaPooja Sharma 《Materials Research Bulletin》2003,38(2):279-288
Synthesis of electroluminescent ZnS:Cu, Br phosphor by a number of routes has been presented along with their brightness-voltage, brightness-frequency, brightness-waveform and spectral energy distribution studies. The sample fired in N2 atmosphere with aluminum and bromine shows predominantly green emission with a peak around 530 nm whereas the sample prepared under H2S and HBr shows the broadest emission spectrum with multiple peaks. These peaks may arise out of different possible bands of copper, self-activated luminescence of ZnS and association of copper with some of the donor levels formed because of the higher reactivity of HBr. All the samples have been found to obey the relation B=B0 exp.(−b/V0.5) which has been discussed using bipolar tunnel emission model. The frequency variation of brightness is linear. Samples containing bromine show multiple secondary peaks indicating that bromine helps in formation of multiple shallow traps. 相似文献
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10.
GaTe is a III–VI semiconductor which has layered structure with large anisotropy in electrical properties. Growth of single
crystals by the Bridgman technique permitted the measurement of thermoelectric power in orthogonal directions from which the
anisotropy of hole effective masses were determined for the first time. From resistivity and Hall effect measurements the
carrier activation energies and scattering mechanisms between 10–300°K were found.
Study of the temperature dependence of conductivity revealed a variety of conduction mechanisms including weak localization
below 20°K, hopping conduction between 20–50 K and band conduction in and across the layer planes atT>70 K. Weak localization was confirmed through observation of negative magnetoresistance. TheI–V characteristics showed quantized behaviour due to tunneling across potential barriers, which may be due to stacking faults
between layer planes as observed by TEM studies. 相似文献