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51.
When the reactant surface is not in a thermal equilibrium, but in a thermo-coherent state we have derived the rate and discussed
about the quantum features of the rate. In the limit of very low and very high temperature the expressions are derived analytically
and compared with the case of thermal distribution. We have investigated the dependence of temperature on the rate due to
displacement, distortion of the harmonic potential energy surfaces of the reactant and product manifold. 相似文献
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55.
The effect of organomodified nanoclay on the morphology and properties of a (70/30 w/w) nylon 6/poly(methyl methacrylate) (PMMA) blend prepared by a melt processing method was investigated. The number average domain diameter (Dn ) of the dispersed PMMA phase was found to decrease with the addition of a small amount [0.5 per hundred resin (phr)] of clay in the blend. A much finer dispersion of the minor phase in the presence of a higher amount (5 phr) of clay indicated better mixing efficiency and improved morphology in the blend. X-ray diffraction indicated the exfoliation of the clays in the nylon 6 matrix, whereas PMMA chains only intercalated into the clay layers. However, the same effect of the clay was not observed in a (30/70 w/w) nylon 6/PMMA blend when nylon 6 became the dispersed domains. In the (30/70 w/w) nylon 6/PMMA blend, the addition of organomodified nanoclay (up to 2 phr) increased the Dn of the nylon 6 domains by preferential location of the clays inside the nylon 6 domains. Addition of styrene-maleic anhydride (SMA) copolymer effectively reduced the Dn of disperse phases in both compositions of the nylon 6/PMMA blends. Thus, in nylon 6/PMMA blends, clay platelets could prevent the coalescence of dispersed domains during melt mixing as long as it was dispersed in the matrix phase of the blend. Mechanical properties and thermal stability of the blends were also improved in the presence of clay. 相似文献
56.
Indranil SenGupta 《Journal of Mathematical Analysis and Applications》2010,369(1):101-48
In this paper we consider a class of problems which are generalized versions of the three-dimensional superradiance integral equation. A commuting differential operator will be found for this generalized problem. For the three-dimensional superradiance problem an alternative set of complete eigenfunctions will also be provided. The kernel for the superradiance problem when restricted to one-dimension is the same as appeared in the works of Slepian, Landau and Pollak (cf. Slepian and Pollak (1961) [1], Landau and Pollak (1961, 1962) [2] and [3], Slepian (1964, 1978) [4] and [5]). The uniqueness of the differential operator commuting with that kernel is indicated. 相似文献
57.
We consider spacetime with torsion in a Randall-Sundrum scenario where torsion, identified with the rank-2 Kalb-Ramond field, exists in the bulk together with gravity. While the interactions of both graviton and torsion in the bulk are controlled by the Planck mass, an additional exponential suppression comes for the torsion zero-mode on the visible brane. This may serve as a natural explanation of why the effect of torsion is so much weaker than that of curvature on the brane. The massive torsion modes, on the other hand, are correlated with the corresponding gravitonic modes and may be detectable in TeV-scale experiments. 相似文献
58.
Chandra Mouli Pandey Srishti Dewan Seema Chawla Birendra Kumar Yadav Gajjala Sumana Bansi Dhar Malhotra 《Analytica chimica acta》2016
We report results of the studies relating to controlled deposition of the amino-functionalized silica-coated zinc oxide (Am-Si@ZnO) nano-assemblies onto an indium tin oxide (ITO) coated glass substrate using Langmuir-Blodgett (LB) technique. The monolayers have been deposited by transferring the spread solution of Am-Si@ZnO stearic acid prepared in chloroform at the air-water interface, at optimized pressure (16 mN/m), concentration (10 mg/ml) and temperature (23 °C). The high-resolution transmission electron microscopic studies of the Am-Si@ZnO nanocomposite reveal that the nanoparticles have a microscopic structure comprising of hexagonal assemblies of ZnO with typical dimensions of 30 nm. The surface morphology of the LB multilayer observed by scanning electron microscopy shows uniform surface of the Am-Si@ZnO film in the nanometer range (<80 nm). These electrodes have been utilized for chronic myelogenous leukemia (CML) detection by covalently immobilizing the amino-terminated oligonucleotide probe sequence via glutaraldehyde as a crosslinker. The response studies of these fabricated electrodes carried out using electrochemical impedance spectroscopy show that this Am-Si@ZnO LB film based nucleic acid sensor exhibits a linear response to complementary DNA (10−6–10−16 M) with a detection limit of 1 × 10−16 M. This fabricated platform is validated with clinical samples of CML positive patients and the results demonstrate its immense potential for clinical diagnosis. 相似文献
59.
Arnaldo Machado da Silva Sumana Chakraborty Puspitapallab Chaudhuri 《International journal of quantum chemistry》2012,112(16):2822-2827
High level ab initio calculations of the Rayleigh scattering activities of the hydrogen‐bonded dimers of formic acid (HCOOH), nitrosyl hydride (HNO), and hydrogen cyanide (HCN) molecules have been performed. All these molecules have already been detected in interstellar space and are of great importance from the astrochemical point of view. The geometries of the homo‐ and hetero‐dimers have been optimized using Hartree–Fock and second‐order Møller‐Plesset perturbation theory. Dipole moment, mean dipole polarizability, and polarizability anisotropy have been calculated utilizing Pople‐type 6‐311++G(d,p) and Dunning's aug‐cc‐pVDZ basis sets for all the complexes. The polarizabilities are then used to calculate and analyze the Rayleigh scattering parameters. The results for the dimers, HCN···HCN, HCOOH···HCOOH, HNO···HNO, HCN···HCOOH, HCN···HNO, and HNO···HCOOH are compared with those of the isolated molecules, HCN, HCOOH, and HNO to see the effect of hydrogen bond formation on the molecular interaction with radiation. © 2011 Wiley Periodicals, Inc. 相似文献
60.
Rahul Bhattacharya Sumana Chanda Gabriele Bocelli Andrea Cantoni Ashutosh Ghosh 《Journal of chemical crystallography》2004,34(6):393-400
The crystal structures of 2-methylbenzimidazolium tetrahalocuprates (H2-mebz)2[CuX4] (X = Cl and Br) have been detemined. The chloride salt is monoclinic, P21/c, with a = 8.540(2) Å, b = 16.591(2) Å, c = 14.303(3) Å, and = 98.69(2)°. The bromide salt is also monoclinic, P21/c, with a = 8.316(3) Å, b = 17.436(3) Å, c = 14.747(3) Å, and = 98.82(3)°. Both the compounds contain discrete distorted tetrahedral CuX4
2– anions and almost planar 2-methylbenzimidazolium cations. In the chloride salt, three chloride ions are involved in hydrogen bonding instead of two bromide ions in the bromide salt. 相似文献