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1.
Chattopadhyay Arup Kumar Nag Amitava Singh Jyoti Prakash 《Multimedia Tools and Applications》2022,81(24):34969-34999
Multimedia Tools and Applications - A secret sharing scheme partitions a secret into a set of shares and distributes them among the eligible participants, with each participant receiving one share... 相似文献
2.
Wireless Personal Communications - A dual purpose system is presented in this paper which serves not only as a door closer, but is equally effective for surveillance purposes. The currently... 相似文献
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5.
Kotteda V. M. Krushnarao Schiaffino Arturo Chattopadhyay Ashesh Shantha-Kumar Sanjay Kumar Vinod Bronson Arturo 《Metallurgical and Materials Transactions B》2019,50(4):1559-1565
Metallurgical and Materials Transactions B - The effect of the surface tension–viscosity dissipation driving liquid Ti flow into a B4C packed bed was analyzed at 1941 K and 2573 K. The model... 相似文献
6.
Ferrite particles coated with biocompatible phases can be used for hyperthermia treatment of cancer. We have synthesized substituted
calcium hexaferrite, which is not stable on its own but is stabilized with small substitution of La. Hexaferrite of chemical
composition (CaO)0.75(La203)0.20(Fe2O3)6 was prepared using citrate gel method. Hydroxyapatite was prepared by precipitating it from aqueous solution of Ca(NO3)2 and (NH4)2HPO4 maintaining pH above 11. Four different methods were used for coating of hydroxyapatite on ferrite particles. SEM with EDX
and X-ray diffraction analysis shows clear evidence of coating of hydroxyapatite on ferrite particles. These coated ferrite
particles exhibited coercive field up to 2 kOe, which could be made useful for hysteresis heating in hyperthermia. Studies
by culturing BHK-21 cells and WBC over the samples show evidence of biocompatibility. SEM micrographs and cell counts give
clear indication of cell growth on the surface of the sample. Finally coated ferrite particle was implanted in Kasaulli mouse
to test its biocompatibility. The magnetic properties and biocompatibility studies show that these hydroxyapatite coated ferrites
could be useful for hyperthermia. 相似文献
7.
S. Sarkar P. Mohan Raj S. Chakraborty G. Phanikumar K. Chattopadhyay P. Dutta 《Journal of Materials Science》2003,38(1):155-164
A three dimensional, transient model is developed for studying heat transfer, fluid flow and mass transfer for the case of a single-pass laser surface alloying process. The numerical study is performed in a co-ordinate system fixed to the laser which moves with a constant scanning speed. The coupled momentum, energy and species conservation equations are solved using a finite volume technique. Phase change processes are modelled using a fixed-grid enthalpy-porosity technique, which is capable of predicting the continuously evolving solid-liquid interface. The three-dimensional model is able to predict the species concentration distribution inside the molten pool during alloying, as well as in the entire cross section of the solidified alloy. Corresponding experimental results show a good qualitative agreement with the numerical predictions with regard to pool shape and final composition distribution. 相似文献
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The present study concerns the effect of copper additions on the microstructural evolution and mechanical properties of directly
quenched Ti–B steels. Ti and B are added as microalloying elements with an aim of achieving adequate austenite hardenability
and Cu is added to retard the austenite (γ) → ferrite (α) transformation. Therefore, the microalloying and Cu additions together allow the transformation of austenite to occur at
a lower temperature, resulting in a finer microstructure containing martensitic constituents. The direct-quenching route is
adopted with an aim of facilitating the nucleation of the constituent phases from the deformed austenite. In order to circumvent
the hot-shortness due to the Cu addition, 0.79 wt% Ni has been added to one of the 1.5 wt% Cu microalloyed steels. The present
study has demonstrated that the Ni-containing 1.5Cu–Ti–B steel is capable of providing an attractive combination of strength
and ductility comparable to the high strength varieties of HSLA steels in directly quenched condition. 相似文献
10.
N. Ravishankar H. I. Aaronson K. Chattopadhyay 《Metallurgical and Materials Transactions A》1994,25(12):2631-2637
The early stages in the formation of α1 plates in the ordered β′ matrix of a Cu-39 pct Zn alloy have been studied with transmission electron microscopy (TEM). The
early stage plates were found to be free of stacking faults. Their contrast features are indeed those normally expected from
small coherent plates. Electron microdiffraction confirms that these plates have the 9R structure characteristic of α1 with the same lattice parameters and orientation relationships reported by previous investigators at much later stages of
growth. Similarly, the 9R structure was disordered, even though it was formed in an ordered matrix, again repeating previous
results obtained at a later stage of growth. These results further support the view that the α1 Cu-Zn plates form by a diffusion-controlled mechanism.
This article is based on a presentation made at the Pacific Rim Conference on the “Roles of Shear and Diffusion in the Formation
of Plate-Shaped Transformation Products,” held December 18-22, 1992, in Kona, Hawaii, under the auspices of ASM INTERNATIONAL’S
Phase Transformations Committee. 相似文献