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1.
A model of contact thermolysis was constructed based on a combined set of equations for heat transfer from a magmatic intrusion to a coal bed and the kinetics of thermal coal conversion. This model was illustrated by the generation of petroleum hydrocarbons deep in the earth by the thermolysis of the sapropelic matter of boghead. 相似文献
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V. M. Piksaikin L. E. Kazakov G. G. Korolev S. G. Isaev V. A. Roshchenko M. Z. Tarasko 《Atomic Energy》2002,92(2):147-155
The relative yield of delayed neutrons and the half-life of their precursor nuclei in fissioning of 233U, 235U, and 239Pu by epithermal neutrons are measured on a setup which is based on a KG-2.5 electrostatic accelerator. The experimental samples are irradiated in a polyethylene cube, one face of which is irradiated by a neutron beam consisting of T(p, n)3He neutrons. A procedure is developed for averaging the group parameters of delayed neutrons from different series of measurements, taking account of their correlation. A comparative analysis of the data of this work and in ENDF/BVI in terms of the average half-life of the precursor nuclei of the delayed neutrons and using the dependence of the reactivity on the asymptotic period of the reactor is performed.It is shown that the data of this work agree, to within the uncertainty limits, with the recommended experimental data and differ substantially from the ENDF/BVI data. 相似文献
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The possibility that progesterone or estradiol may regulate expression of G protein in the rat myometrium during the course of pregnancy has been investigated using 1) immunoblot analysis of Gi2 alpha, Gi3 alpha, and Gq alpha subunits and 2) hybridization blot analysis of subunit mRNA. Eighteen hours after administration, estradiol had significantly increased the levels of both Gi2 alpha subunit and Gi2 alpha mRNA (by 40% and 32%, respectively). In control pregnant rats, we observed similar changes at the end of pregnancy, when myometrial concentrations of estradiol had increased, i.e., a 41% increase in immunoreactive Gi2 alpha subunit that correlated with a parallel 45% increase in mRNA levels. In contrast, levels of immunoreactive Gi3 alpha subunit and mRNA, which decreased with advancing gestation, were not influenced by estradiol or progesterone administration. Progesterone administration resulted 30 h later in a significantly decreased level of Gq alpha immunoreactivity (32%) and Gq alpha mRNA (30%). In control rats, Gq alpha protein and mRNA were also significantly lower at midpregnancy under progesterone dominance vs. term. At this stage, a twofold increase in Gq alpha subunit correlated with a 40% increase in mRNA levels. These results demonstrate that myometrial Gi2 alpha and Gq alpha subunits are physiological targets for estradiol and progesterone, respectively, in vivo. Alterations of these G protein levels are discussed in relation to their mediating effects on adenylyl cyclase activity or the phospholipase C pathway during the course of pregnancy. 相似文献
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The paper compares experimental and calculated pulse shapes and spectra of signals for bidirectional right transducers with radically different protectors, namely, those from epoxy glue with a filler and ceramic. The new data support the previously made conclusion (from calculated parameters of emitted pulses) that in protectors from composite materials (with low propagation velocities of longitudinal elastic waves) signal spectra can have several pronounced peaks, and their waveforms can exhibit beats (oscillating amplitude modulation). 相似文献
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The energy dependence of the relative yield of delayed neutrons and of half-lives of their precursor nuclei with fissioning
239Pu by 14.2–17.9 MeV neutrons is measured. The data obtained are analyzed in terms of the average half-life 〈T〉 of the precursor
nuclei of the delayed neutrons. It is shown that the observed growth of 〈T〉 with increasing primary neutron energy in the
energy range studied is due predominately to opening of the channels for the emission fission of nuclei. Comparing the data
on the average half-life of the precursor nuclei of delayed neutrons obtained in the present work with those obtained by other
authors showed that the anomalously high values of 〈T〉 are due to methodological features of the experiment which are related
with the properties of the reaction T(d, n)4He used as a neutron source on electrostatic charged-particle accelerators. The data obtained are of great value for developing
instrumentational nondestructive means for determining the nuclide composition of nuclear fuel based on the detection of delayed
neutrons.
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Translated from Atomnaya énergiya, Vol. 101, No. 6, pp. 441–444, December, 2006. 相似文献
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