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91.
Deeptangshu S. Chaudhary 《Journal of Polymer Science.Polymer Physics》2008,46(10):979-987
The amylose–water interaction is part of an important equilibrating process within the starch matrix leading to slow recrystallization of amylose chains and growth of anisotropic properties in the starch matrix. This article highlights the influence of nanoclay on (a) the structural development of amylose crystallinity and (b) the rate of water loss from the starch matrix. By varying the nanocomposites level (1.5–4 wt %), a unique microstructure is obtained that “locks” moisture and it was found that on a per unit weight basis of the starch matrix, addition of 4 wt % nanoclay resulted in additional 8.5% water in the matrix. Also, it was found that increasing the nanoclay from 2 to 4% by weight, the composite modulus jumped by 100% indicating excellent interaction between clay nanocomposites and starch polymer. Analysis of the starch crystallinity data indicates that nanocomposites retard the mobility of the starch molecules (specially the long chain amylose component) to restrict the movement of “associated” water around starch and this increases the “locked” water by ~10%. The results strongly suggest that a new structural unit may be formed by amylose–water–clay interaction which enhances the composites properties. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 979–987, 2008 相似文献
92.
A.K. Chaudhary G.C. Bhar 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,98(2):157-166
Tunable near-infrared radiation has been generated in a rubidium titany1 phosphate (RTP) crystal by employing non-collinear difference-frequency mixing (DFM) technique. The input radiation sources are Nd:YAG laser radiation and its second harmonic pumped dye laser radiation. For the generation of 2.0 radiation, the maximum value of the conversion efficiency (quantum) obtained in the process is 49% from the dye (0.6945 μm) to the infrared (2.0 μm) radiation in the 7.9-mm-long crystal. The generated tunable mid-infrared radiation has been used to measure the number density, absorption cross-section and minimum detectable concentration of methane gas in its 2ν3 band in a multi-pass cell at 30.075 Torr pressure. The number density and column density of the methane molecules are found to be 1.068×1018 cm−3 and 3.02×1021 cm−2, respectively, whereas the minimum still-detectable concentration at 1.658 μm wavelength is estimated to be 4.523×1017/cm3. 相似文献
93.
The theory of the continuous flow electrical method for the determination of specific heat of liquids has been extended to the measurements of effective specific heat of packed bed materials consisting of solid-liquid phase systems. Experimental data are reported showing the variation of effective specific heat with mass porosity and saturating liquid specific heat. The weighted arithmetic mean equation of constituent specific heats is in fair agreement with the measured values. 相似文献
94.
Oxidation of dienedicarbonylcobalt dimers has yielded the novel dienetricarbonylcobalt cations, or, in presence of phosphine, the corresponding mono- and di-substituted salts. 相似文献
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Tangential phase-matching has been realised in cesium lithium borate (CLBO) crystal for the first time for the generation
of fourth harmonic (266 nm) of Nd:YAG and third harmonic (226.7 nm) of a dye laser radiation by second harmonic generation
and sum-frequency mixing with the angular tolerance as large as 22 mrad and 21 mrad respectively, over one of the interacting
beams. An energy conversion efficiency of 15% for fourth harmonic generation is obtained with a 5.5 mm thick crystal and with
the average pump powers only 170 and 70 mW. A set of Sellmeier dispersion equations for the CLBO crystal have also been formulated. 相似文献
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Nayak Debasis Sarkar Tanmay Chaudhary N. Vijay Prakash Bharadwaj Mridula Dixit Ghosh Sudipto Adyam Venimadhav 《Journal of Solid State Electrochemistry》2018,22(4):1079-1089
Journal of Solid State Electrochemistry - Sodium-ion batteries are the commercially and environmentally viable next-generation candidates for automobiles. Structural and electrochemical aspects are... 相似文献