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Abstract— The quantum yield and the kinetics of O -induced luminol chemiluminescence was investigated in a broad pH interval at varying luminol and concentrations. It is suggested that the weak chemiluminescence observed is mediated via a luminol-superoxide-adduct proposed to be an a-hydroxyperoxyl radical. At pH 7 the maximum quantum yield of chemiluminescence per initial percent was determined to be 4 times 10-8 . The degree of involvement in phagocytosis and related processes should be viewed against this maximum limit. 相似文献
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C. G. Lindén I. Bergström J. Blomqvist K. -G. Rensfelt H. Sergolle K. Westerberg 《Zeitschrift für Physik A Hadrons and Nuclei》1976,277(3):273-290
Using the204Hg(α, 3n) reaction withα-particles of about 40 MeV, we have proved by applying nowadays conventionalγ-ray spectroscopy in-beam technique, that there are two isomeric states in205Pb at the excitation energies 5,161.3 and 3,195.5 keV having the half-lives 71±3 and 217±5 ns, respectively. These isomeric states have spins and parities 33/2+ and 25/2? and are mainly due to thei 13 2/?3 andi 13 2/?2 p 1 2/?1 configurations, respectively. This conclusion is supported by the experimentalg-factors of these states being ?0.159±0.008 and ?0.0676±0.0011, respectively. It is furthermore shown that theE2 effective neutron charge is the same forE2 transitions from the 33/2+ state in205Pb and from the 12+ state in206Pb as required by the assumption that the208Pb core is responsible for the totalE2 strength of the neutron holes, and that these states are due to thei 13 2/?3 andi 13 2/?2 configurations. The calculatedB(E3) values ofE3 transitions from isomeric states in205Pb and206Pb agree reasonably well with the experimental values as expected from the assumption that theE3-strength should come from particle coupling to the octupole states of the208Pb core. The energies of the six most well established excited states in205Pb with angular momenta in the region 19/2–33/2 were calculated using empirical single-particle energies, empirical two-particle interactions and angular momentum algebra. The average deviation between experimental and calculated energies is ?3 keV and the root mean square deviation 6 keV as compared to the uncertainty ± 5 keV in the nuclear masses used in the calculation. For the orbits concerned the shell model is thus valid with an extremely high precision. The contribution of effective three-particle interaction in these orbits must consequently be less than about 5 keV. 相似文献
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Yuliya B. Lind 《Journal of computational science》2012,3(6):456-459
Methods for decision-making formalization at all stages of drilling process have been developed. They include methods for efficient use of drilling fluids with grounded technological parameters, prediction of troubles during drilling process and construction of optimal well profiles. Software implementing them makes it possible to optimize drilling parameters, improve tailing-in quality and in general to increase technical and economic indices of drilling. Use of parallel computations allows reducing time of computations and increasing their accuracy. 相似文献
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For detailed study of complex chemical reactions mechanisms experiment is conducted for selected private reactions. This causes a problem of kinetic parameters getting—the same set of rate constants must describe both public and private reaction stages, and also a general mechanism. In this paper, solution of this problem for a reaction of olefins hydroalumination is proposed. To optimize the computational process a methodology of parallelization is elaborated. On the base of parallel computations, a kinetic model for the reaction assigned is constructed, and on its base, the physical and chemical conclusions about reaction mechanism are done. 相似文献
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Pengfei Wang Yanquing Shen Shikang Wu Ewa Adamczak Lars-Åke Lindén Jan F. Rabek 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1973-1983
Abstract Polymerization of methyl methacrylate and styrene can be effectively photoinitiated by a binary photoinitiator system consisting of cyclopentadienyl(iron)arene hexafluorophosphonate salt and bis(p-N, N-dimethylaminobenzylidene)cyclopentanone in the spectral range of 400–500 nm. The amine-type radical formed from the exciplex of the binary photoinitiator system is probably responsible for the radical polymerization of vinyl monomers. A probable mechanism of initiation of polymerization is discussed. 相似文献
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An understanding of the phenomena associated with cavitation is important in many areas of science and engineering. This paper is concerned with the influence of viscoelasticity on the dynamics of cavitation bubbles near rigid boundaries. Viscoelastic effects are modelled using a Maxwell constitutive equation, and a generalized Bernoulli equation is derived. The governing equations are solved using the boundary element method in which both the bubble surface and the potential are represented by cubic splines. The numerical scheme is validated through comparisons with results in the literature for the inviscid case. The introduction of viscoelasticity introduces some interesting bubble dynamics including the occurrence of oscillations during collapse. Most importantly, it is shown that viscoelasticity can serve to suppress the formation of a liquid jet. The subsequent reduced pressures compared with the inviscid case suggest that viscoelasticity has a mitigating effect on cavitation damage. 相似文献
20.
T. L. J. Lindén 《International Journal of Theoretical Physics》1973,7(3):159-168
A coupling electromagnetism with a previously developed scalar theory of gravitation is presented. The principle features of this coupling are: (1) a slight alteration to the Maxwell equations, (2) the motion of a charged particle satisfies an equation with the Lorentz force-appearing on the right side in place of zero, and (3) the energy density of the electromagnetic field appears in the gravitational field equation in a manner similar to the mass term in the Klein-Gordonequation. The field of a static, spherically symmetric charged particle is computed. The electromagnetic field gives rise to l/r
2 terms in the gravitational potential. 相似文献