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排序方式: 共有1200条查询结果,搜索用时 31 毫秒
1.
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   
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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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Growth of ultrathin (<100 Å) oxynitride on strained-Si using microwave N2O and NH3 plasma is reported. X-ray photoelectron spectroscopy (XPS) results indicate a nitrogen-rich layer at the strained-Si/SiO2 interface. The electrical properties of oxynitrides have been characterized using a metal-insulator-semiconductor (MIS) structure. A moderately low value of insulator charge density (6.1×1010 cm-2) has been obtained for NH3 plasma treated N2O oxide sample. Nitrided oxide shows a larger breakdown voltage and an improved charge trapping properties under Fowler-Nordheim (F-N) constant current stress  相似文献   
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In the present investigation a higher-order shear deformation theory and the conventional first-order theory are used to develop a finite element method to analyse accurately the bending and free vibration behaviour of laminated composite beams, using nine-noded isoparametric elements. The higher-order theory assumes all the displacement components, u, v and w, which contain variation up to a cubic power of z. The effects of various parameters such as fibre orientation, stacking sequence, span-to-thickness ratio and support condition on the non-dimensionalised deflections, stresses and fundamental frequencies are investigated. Cases where only the higher-order theory is likely to yield accurate results are highlighted.  相似文献   
7.
Furnace grown gate oxynitride using nitric oxide (NO)   总被引:4,自引:0,他引:4  
Gate oxynitride was grown in NO for the first time. This approach can provide a tight N accumulation near the Si/SiO2 interface. Much lower thermal budget is required for an NO process than for an N2O process to produce an oxynitride with useful properties. Submicron MOSFET's with NO oxynitride showed superior current drive characteristics and comparable hot carrier immunity to those with N2O oxynitride  相似文献   
8.
Tanmoy Maiti  E. Alberta  R. Guo  A.S. Bhalla   《Materials Letters》2006,60(29-30):3861-3865
In this paper we report the evolution of the polar cluster like behavior with the incorporation of Ti4+ ion in BaZrO3 Ceramics. Dielectric behavior of BaZrxTi(1−x)O3 (x = 1.00, 0.95, 0.90, 0.85) ceramics is studied in the temperature range from 300 to 30 K. Polar cluster like behavior becomes more prominent with the increase in content of Ti4+ ion. The dielectric relaxation is analyzed by Vogel–Fulcher relation and Arrhenius law. Frequency dependence of dielectric constant and low loss tangent of these materials can be useful for the potential applications at low temperature.  相似文献   
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The approximate energy release rate for a crack which extends, or kinks, away from its original direction has been computed by finite element analysis using three different methods: stiffness derivative procedure, J integral method and crack closure integral procedure. A case study is presented to compare the computational accuracies. It suggests that a satisfactory approximation can be obtained provided that the ratio of kink length to original crack length, l(0)/a0.04, despite the interaction of the crack tip and knee stress singularities.
Résumé En utilisant trois méthodes différentes (dérivation de la raideur, intégrale J et intégrale de fermeture de la fissure), on a calculé par éléments finis la vitesse approchée de relaxation de l'energie dans le cas d'une fissure qui diverge ou qui part en arborescence par rapport à sa direction initiale.On présente une étude de cas de manière à comparer les précisions respectives obtenus dans les calculs.Cette étude suggère qu'une approximation satisfaisante peut être obtenue, pour autant que le rapport de la longueur déviée à la longueur initiale de la fissure soit inférieure ou égale à 0,04, en dépit de l'interaction entre l'extrémité de la fissure et la singularité de la contrainte.
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