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排序方式: 共有3199条查询结果,搜索用时 31 毫秒
31.
Arpita Ghosh A. Jain S. Gharami Subir Kumar Sarkar 《Journal of Computational Electronics》2017,16(2):296-306
A simple small-signal model of the single-electron transistor is presented. The terminal voltage variations are considered to be sufficiently small to result in small current variations that can be expressed using linearized relations. The derivation of such relations and the development of an equivalent circuit to represent them are presented. Two-port analysis of the small-signal circuit of the single-electron transistor is proposed and explained using various parameters such as impedance parameters, admittance parameters, and hybrid parameters. The variation of the magnitude of these parameters is plotted with respect to frequency. The transconductance and drain resistances and their frequency variation are also discussed. The effect of parasitic capacitance on the proposed small-signal model is also analyzed. 相似文献
32.
Phase Transformation of Metastable ZnSnO3 Upon Thermal Decomposition by In‐Situ Temperature‐Dependent Raman Spectroscopy 下载免费PDF全文
Tanujjal Bora Muna H. Al‐Hinai Ashraf T. Al‐Hinai Joydeep Dutta 《Journal of the American Ceramic Society》2015,98(12):4044-4049
Temperature‐dependent in‐situ Raman spectroscopy is used to investigate the phase transformation of zinc metastannate (ZnSnO3) to zinc orthostannate (Zn2SnO4) induced upon annealing in the ambient. ZnSnO3 microcubes (MCs) were synthesized at room temperature using a simple aqueous synthesis process, followed by characterization using electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). Annealing of the ZnSnO3 MCs was carried out up to 1000°C, while recording the Raman spectra in‐situ at regular intervals. Phase transformation from metastannate to orthostannate was found to begin around 500°C with an activation energy of ~0.965 eV followed by the recrystallization into the inverse spinel orthostannate phase at ~750°C. Results from this study provide detailed understanding of the phase transformation behavior of perovskite ZnSnO3 to inverse spinel Zn2SnO4 upon thermal annealing. 相似文献
33.
Nuno Calçada Loureiro Satyabrata Ghosh Júlio C. Viana José Luis Esteves 《Polymer-Plastics Technology and Engineering》2015,54(4):350-356
In this work we present the thermal characterization of the full scope of polyhydroxyalcanoate and poly(lactic acid) blends obtain by injection molding. Blends of polyhydroxyalcanoate and poly(lactic acid) (PHA/PLA) were prepared in different compositions ranging from 0–100% in steps of 10%. The blends were injection molded and then characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and wide angle X-ray diffraction (WAXD). The increment of PHA fraction increased the degree of crystallinity of the blend and the miscibility of the base polymers as verified by the Fox model. The WAXD analysis indicates that the presence of PHA hindered the PLA crystallization. The crystallization evolution trough PHA weight fraction (wf) shows a phase inversion around 50-60%. SEM analyses confirmed that the miscibility of PHA/PLA blends increased with the incorporation of PHA and became total for values of PHA higher that 50%. 相似文献
34.
Effect of Alumina Reactivity on the Densification and Properties of Al2O3–Cr2O3 Refractories 下载免费PDF全文
Mithun Nath Vakiti Pradeep Reddy Somnath Sinhamahapatra Kausik Dana Arup Ghosh Himansu Sekhar Tripathi 《International Journal of Applied Ceramic Technology》2015,12(3):608-613
Alumina‐chrome (Al2O3–Cr2O3) refractories with Al2O3:Cr2O3 molar ratio 1:1 were synthesized in the temperature range of 1400–1700°C by conventional solid–oxide reaction route. The effect of different aluminas (viz., hydrated and calcined) on the densification, microstructure, and properties of Al2O3–Cr2O3 refractories was investigated without changing the Cr2O3 source. The starting materials were analyzed to determine the chemical composition, mineralogy, density, surface area, and particle size. Sintered materials were characterized in terms of densification, phase assemblage, and mechanical strength at room temperature and at higher temperatures. Microstructural evolution at different sintering temperature was correlated with sintering characteristics. It can be concluded that the Al2O3–Cr2O3 refractories prepared with hydrated alumina as Al2O3 source show better densification and hot mechanical strength than corresponding calcined variety. 相似文献
35.
Sajal Ghosh Rajesh Ganesan R. Sridharan T. Gnanasekaran 《Journal of Phase Equilibria and Diffusion》2018,39(6):916-932
The ternary phase diagram of LiCl-KCl-NdCl3 system has been investigated by differential thermal analysis (DTA), followed by characterization of the coexisting phases in the solid state by x-ray diffraction, in order to understand the interactions in the NdCl3-LiCl-KCl ternary system. The results of these experiments showed that LiCl and K2NdCl5 form a non binary join section. This divides the LiCl-KCl-NdCl3 system into two quasi-ternary sections, namely (1) LiCl-KCl-K2NdCl5 and (2) LiCl-K2NdCl5-NdCl3 systems. Both are simple eutectic ternary phase diagrams. The ternary eutectic temperatures and eutectic compositions are determined to be 316?±?3 °C and 53.9 mol.% LiCl-38.7 mol.% KCl-7.4 mol.% K2NdCl5 in the LiCl-KCl-K2NdCl5 quasi-ternary section, while the other eutectic temperature and composition are determined to be 376?±?9 °C and 46.2 mol.% LiCl-32.5 mol.% K2NdCl5-21.3 mol.% NdCl3 in the LiCl-K2NdCl5-NdCl3 quasi-ternary section. A quasi-ternary peritectic reaction is observed at 37.7 mol.% LiCl-36.2 mol.% KCl-26.1 mol.% K2NdCl5 at 445?±?1°C. The primary and secondary crystallization temperatures for the samples are deduced from the heating runs of DTA traces, and the phases responsible for the various thermal events are ascertained. Isothermal sections at chosen temperatures and polythermal liquidus projection with isothermal contours are drawn over the ternary phase field. 相似文献
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38.
Roy Swalpa Kumar Chanda Bhabatosh Chaudhuri Bidyut B. Ghosh Dipak Kumar Dubey Shiv Ram 《Multimedia Tools and Applications》2020,79(7-8):4783-4809
Multimedia Tools and Applications - Methods based on locally encoded image features have recently become popular for texture classification tasks, particularly in the existence of large intra-class... 相似文献
39.
Smarajit Ghosh 《国际能源研究杂志》2020,44(3):2355-2367
Sustainable power sources, that is, the energy produced as of hydro control, biomass, wind, geothermal, sunlight, and sea resources deliberated as innovative choice intended to create clean energy and crisp water. The majority of the nations have challenged issues proceeding freshwater and power creation, which tends to the utilization of sustainable power source-controlled desalination frameworks. In this work expanding the clean water accessibility that satisfies the load need, Hybrid Renewable Energy Systems (HRES) on the basis of Reverse Osmosis Desalination (ROD) is structured and then displayed. HRES is getting to be well known for power applications because of advances in sustainable power sources. Here, an innovative calculation based on Social Spider Optimization (SSO) is aimed at explaining the required optimization tasks. The technique referenced is turned out to be powerful, utilizing sustainable power source framework. The proposed system is contrasted with a genuine contextual analysis in the eastern part of Iran, Canary Islands and outcomes demonstrate that it has been successfully utilized thinking about both power quality and cost. Also, the outcomes acquired by the suggested technique are very encouraging to outline the capability and strength of the introduced methodology. 相似文献
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