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排序方式: 共有1556条查询结果,搜索用时 15 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
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8.
Sujata Swain Sk. Muneer A. R. Sahu A. Mahapatra R. R. Negi B. Samanta 《Integrated ferroelectrics》2020,205(1):186-193
AbstractIn the present work, the effect of high-energy ball milling (HEBM) of starting precursors of hydroxyapatite (Ca10(PO4)6(OH)2)/HA system on the processing temperature, morphological, mechanical, and electrical properties are highlighted. Calcination and sintering of HA system were carried out in microwave furnace. XRD study confirmed the evolution of HA phase and EDX analysis confirmed Ca/P ratio ~1.65. Grain size of HA samples, synthesized by using microwave-assisted HEBM technique was found to be in the order of 54–75?nm. Enhanced dielectric and mechanical properties were obtained in HA samples. 相似文献
9.
Banerjee Amit Mishra P. R. Mohanty Ashok Chakravarty K. Das Biswas R. Sahu R. Chakravarty S. 《国际煤炭科学技术学报(英文)》2016,3(2):97-103
International Journal of Coal Science & Technology - Mineral phase characterization and thorough understanding of its transformation behavior during combustion are imperative to know the... 相似文献
10.
Nisha Deopa Mukesh K. Sahu Sumandeep Kaur Aman Prasad K. Swapna Vinay Kumar R. Punia A.S. Rao 《中国稀土学报(英文版)》2021,39(5):520-525
A series of Er~(3+) ions doped lithium lead alumino borate(LiPbAlB) glasses were synthesized via melt quench method and their structural,physical and optical properties were studied.Judd-Ofelt theory in correlation with the emission and absorption profiles was performed for the measurement of various radiative parameters for different transitions of Er~(3+) doped glasses.The as-prepared glasses show deep green(550 nm) as well as NIR(1532 nm) emission at 380 and 980 nm excitation wavelengths,respectively.The intensity of emission spectra increases with Er~(3+) ions concentration up to 1.5 mol% and beyond quenching is observed.The Dexter theory applied to the emission profiles reveals the interaction between Er~(3+)ions as dipole-dipole in nature.CIE color coordinates are found to fall in the green region of the visible spectrum.It is observed that 1.5 mol% of Er~(3+) ions concentration is optimum to exhibit the maximum quantum efficiency,branching ratios,gain bandwidth,emission cross-section,gain crosssection and aptly suitable for visible and NIR photonic applications. 相似文献