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排序方式: 共有1070条查询结果,搜索用时 31 毫秒
1.
Sahu Anshuman Kumar Mahapatra Siba Sankar 《The International Journal of Advanced Manufacturing Technology》2020,107(3):1017-1023
The International Journal of Advanced Manufacturing Technology - It is of great significance for intelligent manufacturing to study condition monitoring and diagnosis methods to realize early... 相似文献
2.
Gririraj Manoharan Murugan Karuppiah Niroj Kumar Sahu Kaliyan Hembram 《Ceramics International》2018,44(7):7837-7843
In this work, we report the fabrication of a high performance multi-layer varistor (MLV) via water based tape casting method using novel compositions of nanomaterials. Bi2O3, CaO and Co3O4 doped ZnO nanopowders were prepared by solution combustion synthesis (SCS) route, calcined at different temperatures (550, 650, 750 and 850?°C) and characterized by TEM, XRD, SEM and AFM. The nanopowder (crystallite size ~30?nm) calcined at 650?°C for 1?h was used as the starting material for MLV fabrication. Compositions of the slurry containing doped ZnO nanopowders, binder and plasticizer in water solvent were optimized for the fabrication of thick film. The rheological properties of the slurries having different solid loadings were analysed and thick films of various thicknesses (50–500?µm) were prepared by varying the feeding rate of tape casting. The film roughness of 38.3?nm for the thick film made from 40?wt% solid slurry was found to be superior compared to other samples due to the presence of reduced crack and shrinkage. MLV fired at 950?°C for 1.5?h exhibited a coefficient of nonlinearity of 18 and breakdown voltage of 291.5?V that yields superior properties compared to commercial MLVs. 相似文献
3.
Sanjeev A. Sahu 《热应力杂志》2020,43(4):489-502
AbstractPresent study deals with the scattering of a plane wave through an orthotropic thermoelastic slab sandwiched between two elastic half-spaces. Unlike the classical theory of thermoelasticity, we have employed non-classical thermoelastic theories (LS-theory and GL-theory) to analyze the scattering of plane waves. The amplitude ratios for different waves have been computed numerically for the considered generalized theories of thermoelasticity. The effect of the slab thickness on the amplitude ratios has been shown graphically. Moreover, the amplitude ratios of different waves (i.e., reflected, transmitted, forward and backward waves) are compared for different values of slab thickness under both the LS-theory and GL-theory. 相似文献
4.
This paper deals with propagation of Love type waves in a Piezomagnetic layer with corrugated boundaries overlying an inhomogeneous half-space. Inhomogeneity of elastic half-space is caused due to exponential variations in elastic parameters. Dispersion relations are obtained for magnetically open and short cases. Prominent effects of inhomogeneity, layer's width and corrugation on the phase velocity of considered wave are illustrated through graphs. Some particular cases are derived and exhibited through graphs. Also the influence of undulation parameter, elastic parameter, and piezomagnetic coefficient on phase velocity of considered wave has been marked separately. The present study finds its applications in designing and optimization of Love wave sensors and Seismic Acoustic Wave (SAW) devices. Findings may also be used for analytical study of wave propagation in piezomagnetic coupled structures. 相似文献
5.
During present investigations, an attempt was made to understand the effect of mean stress and oxidation on low cycle fatigue (LCF) behaviour of CM 247 DS LC alloy at T?=?850°C. A significant reduction in fatigue life was observed during LCF tests conducted at strain ratio (R) of 0 as compared to R?=??1. Reduction in fatigue life is attributed to the synergistic effect of mean stress, oxidation and the expanding precipitates within the grain boundaries which imparts high stresses at the grain boundary leading to the intergranular cracking. Additionally, to account the effect of mean stress on fatigue life of the alloy CM 247 DS LC empirical relations developed by Smith–Watson–Topper (SWT) and Morrow were used. 相似文献
6.
A.R. Jayakrishnan Kevin V. Alex Athul Thomas J.P.B. Silva K. Kamakshi Navneet Dabra K.C. Sekhar J. Agostinho Moreira M.J.M. Gomes 《Ceramics International》2019,45(5):5808-5818
This work reports the composition dependent microstructure, dielectric, ferroelectric and energy storage properties, and the phase transitions sequence of lead free xBa(Zr0.2Ti0.8)O3-(1-x)(Ba0.7Ca0.3)TiO3 [xBZT-(1-x)BCT] ceramics, with x?=?0.4, 0.5 and 0.6, prepared by solid state reaction method. The XRD and Raman scattering results confirm the coexistence of rhombohedral and tetragonal phases at room temperature (RT). The temperature dependence of Raman scattering spectra, dielectric permittivity and polarization points a first phase transition from ferroelectric rhombohedral phase to ferroelectric tetragonal phase at a temperature (TR-T) of 40?°C and a second phase transition from ferroelectric tetragonal phase - paraelectric pseudocubic phase at a temperature (TT-C) of 110?°C. The dielectric analysis suggests that the phase transition at TT-C is of diffusive type and the BZT-BCT ceramics are a relaxor type ferroelectric materials. The composition induced variation in the temperature dependence of dielectric losses was correlated with full width half maxima (FWHM) of A1, E(LO) Raman mode. The saturation polarization (Ps) ≈8.3?μC/cm2 and coercive fields ≈2.9?kV/cm were found to be optimum at composition x?=?0.6 and is attributed to grain size effect. It is also shown that BZT-BCT ceramics exhibit a fatigue free response up to 105 cycles. The effect of a.c. electric field amplitude and temperature on energy storage density and storage efficiency is also discussed. The presence of high TT-C (110?°C), a high dielectric constant (εr ≈?12,285) with low dielectric loss (0.03), good polarization (Ps ≈?8.3?μC/cm2) and large recoverable energy density (W?=?121?mJ/cm3) with an energy storage efficiency (η) of 70% at an electric field of 25?kV/cm in 0.6BZT-0.4BCT ceramics make them suitable candidates for energy storage capacitor applications. 相似文献
7.
Chandra Sekhar Reddy Gangireddy Xin Wang Yongchun Kan Lei Song Yuan Hu 《Polymer International》2019,68(5):936-945
A novel and highly effective flame retardant (FR), DOPO‐TPMP oligomer, was synthesized by a simple condensation of 4‐(hydroxymethyl)‐2,6,7‐trioxa‐1‐phosphabicyclo[2.2.2]octane‐1‐oxide and phosphorus oxychloride followed by a polycondensation reaction with 6‐(2,5‐dihydroxyphenyl)‐6H‐dibenzo[c,e][1,2]oxaphosphinine‐6‐oxide. The chemical structure of DOPO‐TPMP was well characterized using Fourier transform infrared and NMR spectra. DOPO‐TPMP was used as an additive‐type FR for epoxy resin (EP). The FR properties of the resultant EP composites were investigated by limiting oxygen index (LOI) test, UL‐94 vertical burning test and cone calorimeter measurements. Specifically, the EP composite containing 10.0% DOPO‐TPMP achieved a LOI value of 36.1%, V‐0 rating in the UL‐94 test and a 58% reduction in peak heat release rate. Further mechanism analysis attributed the enhanced flame retardancy to the increased char yield on the addition of DOPO‐TPMP. © 2019 Society of Chemical Industry 相似文献
8.
De Paramita Mandal Sekhar Bhowmick Partha Chanda Bhabatosh 《Pattern Analysis & Applications》2019,22(4):1341-1359
Pattern Analysis and Applications - Decomposition and representation of electrical circuit drawings to a suitable vector form has widespread applications related to data compression, storage,... 相似文献
9.
Chandra Sekhar Yadav G. V. P. Ghali V. S. Baloji N. R. 《Russian Journal of Nondestructive Testing》2021,57(6):486-499
Russian Journal of Nondestructive Testing - Characterization of various industrial components without impairing their future utility increases the necessity of nondestructive testing (NDT)... 相似文献
10.