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Ratha Satyajit Vernekar Dnyanesh Sivaneri Kavin Jagadeesan Dinesh Rout Chandra Sekhar 《Journal of Solid State Electrochemistry》2017,21(6):1665-1674
Journal of Solid State Electrochemistry - In this work, we report the synthesis and electrode applications of iron-carbon nanohybrid particles prepared by carbonization of a nanocomposite of FeOOH... 相似文献
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Manjushree Senapati Narayan C. Samal Ranu Mishra Alaka Patnaik Lalit N. Patnaik Mahendra K. Rout 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5-6):557-566
The kinetics of the mechanism of the polymerization of methyl methacrylate initiated by the glycerol/Mn(III) acetate redox system has been investigated in aqueous sulfuric acid medium in the temperature range of 40 to 50 °C. The effects of glycerol, methyl methacrylate, metal ion, acetic acid, and sulfuric acid on the rates of polymerization have been studied. One striking observation is that the increase in monomer concentration steadily decreases the rate of polymerization, contrary to what was observed in the case of acrylonitrile. On the basis of these observations, an appropriate kinetic scheme and rate expression have been developed. 相似文献
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J.C. Sczancoski L.S. Cavalcante T. Badapanda S.K. Rout S. Panigrahi V.R. Mastelaro J.A. Varela M. Siu Li E. Longo 《Solid State Sciences》2010,12(7):1160-1167
[Ba1–xY2x/3](Zr0.25Ti0.75)O3 powders with different yttrium concentrations (x = 0, 0.025 and 0.05) were prepared by solid state reaction. These powders were analyzed by X-ray diffraction (XRD), Fourier transform Raman scattering (FT-RS), Fourier transform infrared (FT-IR) and X-ray absorption near-edge (XANES) spectroscopies. The optical properties were investigated by means of ultraviolet–visible (UV–vis) absorption spectroscopy and photoluminescence (PL) measurements. Even with the addition of yttrium, the XRD patterns revealed that all powders crystallize in a perovskite-type cubic structure. FT-RS and FT-IR spectra indicated that the presence of [YO6] clusters is able to change the interaction forces between the O–Ti–O and O–Zr–O bonds. XANES spectra were used to obtain information on the off-center Ti displacements or distortion effects on the [TiO6] clusters. The different optical band gap values estimated from UV–vis spectra suggested the existence of intermediary energy levels (shallow or deep holes) within the band gap. The PL measurements carried out with a 350 nm wavelength at room temperature showed that all powders present typical broad band emissions in the blue region. 相似文献
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Summary In the present study, a new approach for the determination of ', that is, radical substituent parameter, has been described. The technique is based on two equations, one reported byYamamoto andOtsu and the other byStreitwieser andPerrin. The system used for the determination of the radical substituent parameter (') was Ce(IV) — substituted toluenes — acrylonitrile system. To explain inhibition, it has been suggested that the reaction scheme involves initiation of polymerization by Ce(IV) and termination by primary radical of the substrate. The kinetic expression based on the reaction scheme formulated could explain the unusual observation of a negative intercept found in the plot of [M]/R
p versus 1/[M]. Whereas a plot of log /0 against + did not give a straight line, a good linear plot with zero intercept was obtained when log /0 was plotted against (+ + '). This proves the validity of ' values which have been determinded. 相似文献
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Manjushree Senapati Narayan C. Samal Ranu Mishra Bibekananda Tripathy Swoyam P. Rout Mahendra K. Rout 《Journal of polymer science. Part A, Polymer chemistry》1983,21(2):407-413
The kinetics of polymerization of acrylonitrile(AN) initiated by manganese(III) acetate in the presence of glycerol was investigated in the temperature range of 30–40°C. The effect of varying the concentrations of glycerol, sulfuric acid, acetic acid, metal ion, and monomer on the rate was studied. A suitable reaction scheme and rate expression have been proposed. Termination was mutual and was caused by the combination of two growing polymer radicals. 相似文献
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G. C. Rout M. Seshasayee G. Aravamudan K. Radha 《Journal of chemical crystallography》1984,14(2):193-204
The synthesis, properties, and structural characterization of the title compound, C16H30N4O4S7Te(IV)·H2O, are reported. The crystals are monoclinic, space groupP21/n, withZ=4 in a unit cell of dimensionsa=13.291(5),b=21.306(6),c=10.450(1) Å, 0=104.25(2)° and,V
c=2868 Å3. The structure was solved by the heavy atom method and refined by full-matrix least squares toR=0.025 andR
w
=0.027 for 2894 reflections. The dithiocarbamate groups are linked in an unequal bidentate manner with Te-S average distance 2.695(1) Å. The thiocyanate group is bonded through the sulfur atom with much larger Te-S length [2.964(2) Å]. 相似文献
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Graft copolymerization of methyl methacrylate (MMA) onto chemically modified coir fiber was studied using a CuSO4–KIO4 combination as initiator in an aqueous medium in the temperature range of 50–70 °C. Concentrations or [IO4−] = 0.005 mol/l and [Cu2+] = 0.002 mol/l produce optimum grafting. The effects of time, temperature, amount of coir fiber, some inorganic salts and organic solvents on graft yield have also been investigated. On the basis of experimental findings, a reaction mechanism has been proposed. Evidence of grafting was studied from fourier transform infrared spectroscopy and scanning electron microscopy of chemically modified coir and MMA‐grafted coir. Tensile properties such as maximum stress at break, extension at break and Young's modulus of untreated, defatted, chemically treated and grafted coir fibers were evaluated and compared. Grafted coir fiber showed an increase in tensile properties such as maximum stress at break, extension at break and Young's modulus. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献