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911.
Gagan Kumar Ritu Rani Sucheta Sharma Khalid M. Batoo M. Singh 《Ceramics International》2013,39(5):4813-4818
Cobalt substituted Mg–Mn nanoferrites with formulae Mg0.9Mn0.1CoxFe2?xO4, x=0.0, 0.1, 0.2 and 0.3, have been synthesized for the first time by the solution combustion technique. The effects of Co2+ ions on the dc resistivity, dielectric constant and dielectric loss tangent of Mg–Mn nanoferrites at room temperature are presented in this paper. X-ray diffraction confirmed the formation of a single phase spinel structure. Particle size was found to increase, 20.9–23.9 nm, with increasing Co2+ concentration. The dc resistivity was increased by two order of magnitude with substitution of Co2+ ions while the dielectric constant was found to be decreasing with the increasing concentration of cobalt ions. The value of dc resistivity obtained for Mg0.9Mn0.1Fe2O4 nanoferrite in our work is greater than the value obtained for the same composition prepared by the conventional ceramic technique. Further, the dielectric constant and dielectric loss tangent were observed to be decreasing with the increase in frequency. 相似文献
912.
The study analyses the fuelwood characteristics of 26 trees including shrub species from the dry deciduous forest in Aravally region, Rajasthan, Western India was carried out to explore trees with potential for fuelwood production. Fuelwood value index (FVI) based on the properties of calorific value, wood density and ash. Calorific value was ranged between 18.54 ± 0.04 and 27.44 ± 0.09 KJ g−1 in Jatropha curcus and Wrightia tinctoria respectively. Wood density varied from 0.538 ± 0.01 to 0.966 ± 0.07 g/cm3 in J. curcus and Acacia nilotica. Same way ash and moisture content was highest in J. curcus (3.38 ± 0.19%) and Sterculia urens (70.28 ± 7.52%) and lowest in Miliusa tomentosa (0.85 ± 0.06%) and Azadirachta indica (30.7 ± 10.02%) respectively. On the basis, of the 26 species analyzed, M. tomentosa has the highest FVI, followed by Lannea coromandelica, Acacia leucophloea, Madhuca indica, A. nilotica, W. tinctoria, Butea monosperma, Zizyphus nummularia, S. urens, Boswellia serrata, A. indica, Grewia tenax, Syzygium cuminii, Tectona grandis and Dalbergia sissoo were shown to have promising fuelwood production. 相似文献
913.
Ravishankar S. Dudhe Jasmine Sinha D.S. Sutar Anil Kumar V. Ramgopal RaoAuthor vitae 《Sensors and actuators. A, Physical》2011,171(1):12-18
The organic field effect transistors (OFETs) with regioregular poly 3-hexylthiophene (rr-P3HT) and hexafluoro-2-propanol-substituted polysiloxane (SXFA) as an organic layer, have been used for detection of explosive vapors with excellent sensitivity of less than 70 ppt for 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and less than 100 ppt for 2,4,6-trinitrotoluene (TNT). The sensor response (% change in saturation current) was found to be 125 ± 10% for TNT and 90 ± 10% for RDX. It was also observed that the incorporation of CuII tetraphenylporphyrin (CuTPP) into rr-P3HT/SXFA matrix resulted in an improved selectivity for the vapors of nitro based analytes (TNT, RDX and DNB) as compared to the vapors of non explosive oxidizing agents such as nitrobenzene (NB), benzoquinone (BQ) and benzophenone (BP). This is attributed to the increased binding of the vapors containing nitro compound to the thin films due to the presence of CuTTP. Spin coated thin films were further characterized by Atomic Force Microscopy (AFM) and Electrostatic Force Microscopy (EFM). 相似文献
914.
Stolyarov V. V. Frolova A. V. Tilak Kumar J. V. Sudha J. 《Metal Science and Heat Treatment》2021,63(5-6):334-340
Metal Science and Heat Treatment - The TRIP effect and deformation behavior of metastable austenitic steel were studied under tension in the temperatures range from –120 to +200°C. The... 相似文献
915.
Ranganatha R. Kumar V. Anil Gupta R. K. Bhat R. R. 《Metal Science and Heat Treatment》2021,63(1-2):42-46
Metal Science and Heat Treatment - The effect retrogression and re-aging (RRA treatment) on the tensile properties in the transverse direction of extruded rods from aluminum alloy AA7049 is... 相似文献
916.
A 2D model for the potential distribution in silicon film is derived for a symmetrical double gate MOSFET in weak inversion. This 2D potential distribution model is used to analytically derive an expression for the subthreshold slope and threshold voltage. A drain current model for lightly doped symmetrical DG MOSFETs is then presented by considering weak and strong inversion regions including short channel effects, series source to drain resistance and channel length modulation parameters. These derived models are compared with the simulation results of the SILVACO (Atlas) tool for different channel lengths and silicon film thicknesses. Lastly, the effect of the fixed oxide charge on the drain current model has been studied through simulation. It is observed that the obtained analytical models of symmetrical double gate MOSFETs are in good agreement with the simulated results for a channel length to silicon film thickness ratio greater than or equal to 2. 相似文献
917.
Through-silicon vias (TSVs) have provided an attractive solution for three-dimensional (3D) integrated devices and circuit technologies with reduced parasitic losses and power dissipation, higher input-output (I/O) density and improved system performance. This paper investigates the propagation delay and average power dissipation of single-walled carbon nanotube bundled TSVs having different via radius and height. Depending on the physical configuration, a comprehensive and accurate analytical model of CNT bundled TSV is employed to represent the via (vertical interconnect access) line of a driver-TSV-load (DTL) system. The via radius and height are used to estimate the bundle aspect ratio (AR) and the cross-sectional area. For a fixed via height, the delay and the power dissipation are reduced up to 96.2% using a SWCNT bundled TSV with AR = 300 : 1 in comparison to AR = 6 : 1. 相似文献
918.
Pramod Chaitanya Ritu Mishra Pradeep Kumar Ahirwal O. P. Thakur Lakshman Pandey 《Integrated ferroelectrics》2015,159(1):121-126
The electrical behavior of strontium titanate borosilicate glass ceramics (SrO.TiO2- 2SiO2.B2O3) with additives K2O, La2O3, CoO and Nb2O5 was studied by using Impedance Spectroscopy as a function of temperature and composition. An equivalent circuit model having three parallel RC's connected in series with a capacitor C4 could represent the data well. By comparing the complex modulus plots with simulated ones and looking at the values of the time constants these RC's were attributed to represent crystalline, glassy and glass-crystal interface regions of the glass- ceramic whereas C4 represented the glass-ceramic sample and contact electrode interface. When the glass ceramic sample contained only SrTiO3 crystalline phase and the remaining glassy matrix, the interface capacitance showed an Arrhenius type of nature with an activation energy (0.11 ± 0.04) eV and when the glass- ceramic sample contained number of crystalline phases no clear cut trend appeared. These findings are useful in selecting suitable electrodes for applications as well as in deciding upon experimental techniques for measurement of dielectric constants of materials. 相似文献
919.
920.
Yunhua Shi Devendra Kumar Namburi Miao Wang John Durrell Anthony Dennis David Cardwell 《Journal of the American Ceramic Society》2015,98(9):2760-2766
Single grain (RE)‐Ba‐Cu‐O (RE: Sm, Gd, Y) high‐temperature superconductors are able to generate high magnetic fields. However, the relatively high cost of the raw materials and the low yield of the manufacturing process have impeded the development of practical applications of these materials to date. This article describes a simple, reliable, and economical method of recycling failed bulk (RE)‐Ba‐Cu‐O (RE: Sm, Gd, Y) samples. Sixty‐four failed bulk samples, with diameters up to 31 mm, were recycled with a yield of 90%. The key innovation in this recycling process involves reintroducing the liquid phase into the melt process, which is normally lost during the primary peritectic processing of these materials. This enables the direct re‐growth of failed samples from solid form without the need for re‐grinding into powder. We also demonstrate that the superconducting performance and microstructure of the recycled samples is similar to that of the primary grown samples. 相似文献