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排序方式: 共有265条查询结果,搜索用时 15 毫秒
131.
This paper uses the finite element method to analyse the generation and evolution of residual stress in silicon-on-sapphire thin film systems during cooling. The effects of material properties, thin film structures and processing conditions, on the stress distribution were explored in detail. It was found that under certain conditions, significant stress concentration and discontinuity can take place to initiate crack and/or delamination in the systems. However, these can be minimised by controlling the buffer layer thickness. 相似文献
132.
133.
We employ the technique of weak measurement in order to enable preservation of teleportation fidelity for two-qubit noisy channels. We consider one or both qubits of a maximally entangled state to undergo amplitude damping, and show that the application of weak measurement and a subsequent reverse operation could lead to a fidelity greater than 2/3 for any value of the decoherence parameter. The success probability of the protocol decreases with the strength of weak measurement, and is lower when both the qubits are affected by decoherence. Finally, our protocol is shown to work for the Werner state too. 相似文献
134.
Sumanta Kumar Sahu Arindam Chakrabarty Dipsikha Bhattacharya Sudip K. Ghosh Panchanan Pramanik 《Journal of nanoparticle research》2011,13(6):2475-2484
The aim of this study was to develop a simple, cheap, and rapid method for purification of His-tag recombinant proteins with
high yields. The new immobilized metal ion affinity adsorbent containing superparamagnetic nanoparticles and hydrophilic resins
are proposed here to improve the purification of His-tagged recombinant proteins. In this report, we have described the preparation
of nanosized superparamagnetic nanoparticles (Fe3O4) which were prepared by chemical precipitation method followed by surface modification using phosphonomethyl iminodiacetic
acid. The stable surface functionalized nanoparticles were further linked with Ni2+ for purification of 6× His-tagged proteins. The phosphonate group of the N-phosphonomethyl iminodiacetic acid ligand acts as a surface anchoring agent on magnetite nanoparticles and the remaining
free –COOH groups outside for binding with Ni2+ ions. The nanoparticles were approximately 6–8 nm in size and were stable and had negligible non-specific binding for protein.
The proteins were purified within 1 h and observed on sodium dodecyl sulfate-polyacrylamide electrophoresis gel. 相似文献
135.
Susmita Pradhan Mahuya Bhattacharyya Banerjee Dr. Sudip Biswas Dr. Nor Aliya Hamizi Prof. Dipak K. Das Prof. Radhaballabh Bhar Prof. Rajib Bandyopadhyay Prof. Panchanan Pramanik 《Electroanalysis》2021,33(2):383-392
Herein we developed a simple, cost effective, electrochemical sensor based on nanosized copper telluride (nps-CuTe) for simultaneous detection of epinephrine (EP) and uric acid (UA). Voltammetric responses suggests dramatical improvement of electrocatalytic properties of both molecules by incorporating CuTe nps into unmodified graphite paste electrode (bare GP). Differential pulse voltammetric (DPV) measurement depicts large potential separation of 128 mV between EP and UA, allows their simultaneous determination from binary mixture. Under optimized condition, CuTe modified graphite paste electrode (CuTe/GP) manifested linear relationships of EP and UA in the range of 5–60 μM and 5–120 μM with detection limit (S/N=3) of 18 nM and 32 nM respectively. Moreover, CuTe/GP showed satisfactory response towards pharmaceutical and clinical samples for determining EP and UA concentrations. 相似文献
136.
Sayan Pramanik Suvendu Maity Prasanta Ghosh Chhanda Mukhopadhyay 《Tetrahedron letters》2019,60(5):435-438
An acid-promoted multicomponent reaction for the direct C(sp3)N bond formation was achieved through intermolecular allylic amidation in a one-pot operation to synthesize 7-acetamido tetrahydroindole derivatives from simple and readily available arylglyoxal monohydrates, acetonitriles, and enamines of 5,5-dimethyl-1,3-cyclohexadione (dimedone) has been developed. Here acetonitrile acts both as solvent and reagent. These tetahydroindole derivatives are formed through domino condensation of the enamines and arylglyoxals followed by annulation and allylic amidation. 相似文献
137.
138.
Dr. Suman Pramanik Anthony Fernandes Dr. Virginie Liautard Dr. Mathieu Pucheault Dr. Frederic Robert Prof. Dr. Yannick Landais 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(3):728-732
Pd-nanoparticle-catalyzed dehydrogenative coupling between various hydrosilanes and alcohols was shown to provide silyl ethers in good and reproducible yields. The synthetic methodology is effective for a wide range of simple and bulky silanes and secondary alcohols, while keeping various other functional groups intact. The procedure also exhibits high selectivity for the silylation of primary versus secondary alcohols in 1,2-diols, and allows the successive silylation of alkynols and hydrogenation of the triple bond to afford Z-alkenols in good yields. 相似文献
139.
Let
E ì \mathbbR{E \subset\mathbb{R}} be a closed set of Hausdorff dimension α. Weprove that if α is sufficiently close to 1, and if E supports a probability measure obeying appropriate dimensionality and Fourier decay conditions, then E contains non-trivial 3-term arithmetic progressions. 相似文献
140.
Susmita Pradhan Rashmita Das Radhaballabh Bhar Rajib Bandyopadhyay Panchanan Pramanik 《Journal of nanoparticle research》2017,19(2):69
A new simple chemical method for synthesis of nanocrystalline bismuth telluride (Bi2Te3) has been developed by microwave assisted reduction of homogeneous tartrate complexes of bismuth and tellurium metal ions with hydrazine. The reaction is performed at pH 10. The nano-crystallites have rhombohedral phase identified by XRD. The size distribution of nanoparticle is narrow and it ranges between 50 to 70 nm. FESEM shows that the fine powders are composed of small crystallites. The TEM micrographs show mostly deformed spherical particles and the lattice fringes are found to be 0.137 nm. Energy dispersive X-ray spectroscopy (EDX) analysis shows the atomic composition ratio between bismuth and tellurium is 2:3. Thermoelectric properties of the materials are studied after sintering by spark plasma sintering method (SPS). The grain size of the material after sintering is in the nanometer range. The material shows enhanced Seebeck coefficient and electrical conductivity value at 300 K. The figure of merit is found to be 1.18 at 300 K. 相似文献