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51.
J. S. Binoj B. S. S. Daniel S. S. Saravanakumar 《International Journal of Polymer Analysis and Characterization》2016,21(2):112-122
Natural fibers are being used as reinforcing materials for polymer composites due to their eco-friendly properties. Areca fruit husk fiber (AFHF) is one such fiber; it is currently discarded waste from the tobacco industry, but has huge potential. It is light in weight with a perforated surface that enables good bonding with a polymer matrix. In this study, comprehensive characterization of physical, chemical, thermal, mechanical, and microstructural properties was carried out on the fiber and the composite made with that fiber to optimize the fiber content. The optimum fiber content is found to be 40 wt.%, whereas beyond that, fiber pull-out and debonding reduces the load-bearing capacity of the composite. The specific properties of AFHF polymer composite are even higher than that of the popular E-glass fiber composite, which positions AFHF composite as an alternative structural material. 相似文献
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Duraisamy Saravanakumar Subramaniyan Iyyampillai Muthusamy Kandaswamy 《Tetrahedron letters》2008,49(1):127-132
Two new chromogenic receptors 4-nitro-2-[(phenylhydrazoimino)methyl]phenol (1) and 4-nitro-2-[(4-nitrophenylhydrazoimino)methyl]phenol (2) containing a nitro group as a signalling unit and OH and NH groups as binding sites have been synthesized and characterized by spectroscopic techniques and XRD. Both receptors show colorimetric responses and UV-vis spectral changes in the presence of fluoride ions in organic solvents. 相似文献
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Elangovan A Kao KM Yang SW Chen YL Ho TI Su YO 《The Journal of organic chemistry》2005,70(11):4460-4469
A new series of pi-conjugated donor-acceptor compounds (1-6) with inherent redox centers have been prepared and studied with respect to their electronic properties. The photophysical characteristics of these compounds have been studied in relation to their structures. Cyclic voltammetry and UV-vis spectroelectrochemistry were used to probe the ground-state electronic properties of the neutral and charged species. The observed electronic absorption properties of the neutral and charged molecules are explained with the help of frontier orbital structures and electrostatic potential maps obtained from density functional theory (DFT, B3LYP/6-31G) calculations. Electrochemiluminescence (ECL) of this series of donor-substituted phenylethynylanthronitriles with different donors was also studied. The structure-property relationship of all of the compounds is discussed. 相似文献
54.
S. Elangovan S. Mullainathan 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(5):1006-1010
Density (ρ), viscosity (η), and ultrasonic velocity (U) have been measured for binary mixtures of methyl formate with 1-butanol, 1-pentanol and 1-hexanol at 303 K. From the experimental results, adiabatic compressibility (β), acoustic impedance (Z), viscous relaxation time (τ), free length (Lf), free volume (Vf), internal pressure (πi), and Gibbs free energy (ΔG) have been determined. Excess values of various parameters have also been calculated and interoperated in terms of molecular interactions. The deviations in the parameters show that strength of intermolecular interactions between methyl formate with selected 1-alcohols have been observed in the order of 1-butanol < 1-pentanol < 1-hexanol. 相似文献
55.
K. Santhanam A. Kumaravel S. S. Saravanakumar V. P. Arthanarieswaran 《International Journal of Polymer Analysis and Characterization》2016,21(3):267-274
Natural fibers extracted from plants play a major role as reinforcement in polymer composite materials due to their superior properties. This work aims to comprehensively characterize the physical and chemical properties of Ipomoea staphylina fibers (ISFs), which are extracted from the stem of the Ipomoea staphylina plant. The ISFs show cellulose content (72.76 wt%), hemicelluloses content (13.6 wt%), density (1401 kg cm?3), and tensile strength of 173–658 MPa with a strain rate of 2.03–6.63%. The thermal stability of ISFs illustrate that the fibers are stable up to a temperature of 311°C with kinetic activation energy of 99.82 kJ mol?1. 相似文献
56.
In the present study, hexavalent chromium (Cr(VI)) reduction potential of chromium reductase associated with the cell-free
extracts (CFE) of Arthrobacter rhombi-RE species was evaluated. Arthrobacter rhombi-RE, an efficient Cr(VI) reducing bacterium, was enriched and isolated from a chromium-contaminated site. Chromium reductase
activity of Arthrobacter rhombi-RE strain was associated with the cell-free extract and the contribution of extracellular enzymes to Cr(VI) reduction was negligible.
NADH enhanced the chromium reductase activity. The enzyme activity was optimal at a pH of 5.5 and a temperature of 30 °C.
Among the ten electron donors screened, sodium pyruvate was the most effective one followed by NADH and propionic acid. Michaelis–Menten
constant, K
m, and maximum reaction rate, V
max, obtained from the Lineweaver–Burk plot were 48 μM and 4.09 nM/mg protein/min, respectively, in presence of NADH as electron
donor and 170.5 μM and 4.29 nM/mg protein/min, respectively, in presence of sodium pyruvate as electron donor. Ca2+ enhanced the enzyme activity while Hg2+, Cd2+, Ba2+, and Zn2+ inhibited the enzyme activity. Among the various immobilization matrices screened, calcium alginate beads seemed to be the
most effective one. Though immobilized enzyme system was able to reduce Cr(VI), the performance was not very encouraging in
continuous mode of operation. 相似文献
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V. Gokulakrishnan S. Parthiban E. Elangovan K. Jeganathan D. Kanjilal K. Asokan R. Martins E. Fortunato K. Ramamurthi 《Radiation Physics and Chemistry》2012,81(6):589-593
Molybdenum (0.5 at%) doped indium oxide thin films deposited by spray pyrolysis technique were irradiated by 100 MeV O7+ ions with different fluences of 5×1011, 1×1012 and 1×1013 ions/cm2. Intensity of (222) peak of the pristine film was decreased with increase in the ion fluence. Films irradiated with the maximum ion fluence of 1×1013 ions/cm2 showed a fraction of amorphous nature. The surface microstructures on the surface of the film showed that increase in ion fluence decreases the grain size. Mobility of the pristine molybdenum doped indium oxide films was decreased from ~122 to 48 cm2/V s with increasing ion fluence. Among the irradiated films the film irradiated with the ion fluence of 5×1011 ions/cm2 showed relatively low resistivity of 6.7×10?4 Ω cm with the mobility of 75 cm2/V s. The average transmittance of the as-deposited IMO film is decreased from 89% to 81% due to irradiation with the fluence of 5×1011 ions/cm2. 相似文献