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1.
T. Brian Cavitt Brian Phillips Charles E. Hoyle Bo Pan Sukhendu B. Hait Kalyanaraman Viswanathan Sonny Jnsson 《Journal of polymer science. Part A, Polymer chemistry》2004,42(16):4009-4015
Three‐component photoinitiators comprised of an N‐arylphthalimide, a diarylketone, and a tertiary amine were investigated for their initiation efficiency of acrylate polymerization. The use of an electron‐deficient N‐arylphthalimide resulted in a greater acrylate polymerization rate than an electron‐rich N‐arylphthalimide. Triplet energies of each N‐arylphthalimide, determined from their phosphorescence spectra, and the respective rate constants for triplet quenching by the N‐arylphthalimide derivatives (acquired via laser flash photolysis) indicated that an electron–proton transfer from an intermediate radical species to the N‐arylphthalimide (not energy transfer from triplet sensitization) is responsible for generating the initiating radicals under the conditions and species concentrations used for polymerization. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4009–4015, 2004 相似文献
2.
3.
A four-noded rectangular element with seven degrees of freedom at each node is developed for buckling analysis of laminated plate structures having any number of layers with a constant thickness of individual layers. The displacement model is so chosen that it can explain adequately the parabolic distribution of transverse shear stresses and the non-linearity of in-plane displacements across the thickness. A geometrical stiffness matrix is developed using in-plane stresses. A wide range of plates from thick to thin are examined under uniaxial loading conditions. The results are compared with the existing analytical and numerical solutions. The present formulations confirm its applicability for buckling analysis of a wide range of plates. 相似文献
4.
Within the framework of the covariant simultaneous approach of quantum field theory, a complex system of two identical scalar particles with third- and fourth-order self-action is examined. Explicit forms of the retarded component of the Green's two-time function and of the energy-dependent interaction operator of the system are obtained in the lowest orders of perturbation theory. Three-dimensional quasi-potential equations for the relativistic wave function of a bound state are derived. Based on the results obtained, a complex system of two Higgs bosons is examined. 相似文献
5.
Schwinger variational principle has been used to calculate triple differential cross-sections for ionization of hydrogen atoms
by positrons at intermediate and high energies for Ehrhardt type asymmetric geometry. The results agree in general with the
calculations of Brauneret al [8] and with the second Born calculation. 相似文献
6.
J. Pal C. C. Dey S. Bose B. K. Sinha M. B. Chatterjee D. P. Mahapatra 《Zeitschrift für Physik A Hadrons and Nuclei》1987,356(3):281-286
The analogue of the 0+ ground state in 118Sn has been observed in the compound nucleus 118Sb through 117Sn(p,n γ) 117Sb reaction. The neutron decays of this analogue resonance have been studied from the deexciting γ-rays of the residual nucleus 117Sb. From off resonance excitation functions, spin assignments have been made to states in 117Sb, on the basis of Hauser-Feshbach formalism. The resonance parameters of the isobaric analogue resonance have been determined, including the total, proton and neutron decay widths. 相似文献
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8.
Abstract —Thymine starvation prior to 254 nm ultraviolet light (UV) exposures has been found to decrease the level of maximum photoreactivation in Escherichia coli B s-1 . The dark equilibrium level of photoreactivating enzyme-substrate complexes was determined from the levels of photoreactivation obtained with exposures to single flashes of high-intensity light. The kinetics indicate that photoreactivating enzyme concentration does not decrease as a result of thymine starvation. The UV sensitivities of normal and thymine-starved cells are found to be the same. Photoreactivation by sequential flashes shows a lesser number of total photorepairable lesions in starved cells. It is concluded that thymine starvation renders a portion of the dimers inaccessible to the photoreactivating enzyme, thus lowering the level of maximum photoreactivation. 相似文献
9.
Suresh C. Shrivastawa Vikash C. Garg Arun K. Dey 《Fresenius' Journal of Analytical Chemistry》1969,248(5-6):305-306
Summary Eriochromecyanine RC has been used as chromogenic reagent for the photometric determination of rhodium(III) on a micro scale. A coloured Rh(III)-ECRC chelate with
max 530 nm at pH 4.0 (25°C) is formed. A detailed study has been made concerning to characteristics, composition and stability of the chelate. Standard deviation was ±1.17%.
Über die photometrische Bestimmung von dreiwertigem Rhodium mit Eriochromcyanin RC
Zusammenfassung Ergebnisse einer Untersuchung über die Zusammensetzung und Stabilität des Komplexes werden mitgeteilt. Das Absorptionsmaximum liegt bei 530 nm (pH 4,0; 25°C). Bestimmungen konnten mit einer Standardabweichung von ±1,17% durchgeführt werden.相似文献
10.
Mukul Biswas Sukhendu K. Das 《Journal of polymer science. Part A, Polymer chemistry》1981,19(12):3155-3164
A new polymeric azodye has been synthesized from carbazole by diazotization of its derivative N-methylcarbazole-3,6-diamine and subsequent coupling reaction with 2,2-bis(4-hydroxyphenyl-3-sulfonate-Na)-propane prepared from bisphenol-A. Its physico-chemical, electrical, and thermal properties have been characterized; finally, its application to the preparation of colored semiconductive films from polyvinyl alcohol has been studied. 相似文献