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991.
992.
On the basis of a geological - volcanological - geophysical survey, integrated with petrological and geochronological data, a structural model, including a shallow magmatic body, was defined for the Ribeira Grande area, Sao Miguel island (Azores). Two series of production tests were carried out in the Pico Vermelho 1 and Ribeira Grande 1 wells, which led to a preliminary definition of the deep fluid circulation. The data obtained from these studies were used to reconstruct a preliminary model of the Ribeira Grande geothermal field. 相似文献
993.
994.
995.
Effect of cationic surfactant and inorganic anions on the electrochemical behavior of carbon steel in formation water 总被引:2,自引:0,他引:2
M.A. Deyab 《Corrosion Science》2007,49(5):2315-2328
Corrosion behavior of carbon steel in formation water associated crude oil from Egyptian western desert was studied at various concentrations of dodecyl dimethyl ammonium chloride (CS) as a cationic surfactant. Polarization curves indicate that CS has a good inhibition efficiency for carbon steel in formation water and behaves as cathodic inhibitor. The inhibition efficiency was found to increase with increase in CS concentration until reaches a maximum constant value corresponding to the critical micelle concentration of CS and decrease with increase in solution temperature. The adsorption of CS follows the kinetic thermodynamic model and Flory-Huggins isotherm. Thermodynamic parameters obtained indicate that that the presence of the CS increases the activation energy. Polarization and Impedance measurements indicate that the addition of KI has a significant synergistic effect with CS and results in increase the inhibition efficiency of CS in formation water. 相似文献
996.
997.
998.
The tree representation of evolutionary relationship oversimplifies the view of the process of evolution as it cannot take into account the events such as horizontal gene transfer, hybridization, homoplasy and genetic recombination. Several algorithms exist for constructing phylogenetic networks which result from events such as horizontal gene transfer, hybridization and homoplasy. Very little work has been published on the algorithmic detail of phylogenetic networks with constrained recombination. The problem of minimizing the number of recombinations in a phylogenetic network, constructed using binary DNA sequences, is NP-hard. In this paper, we propose a pattern recognition-based O(n2) time approach for constructing the phylogenetic network, where n is the number of nodes or sequences in the input data. The network is constructed with the restriction that no two cycles in the network share a common node. 相似文献
999.
V. P. Vasilevskii M. N. Mikhailov A. A. Petrov M. I. Rozhdestvenskii Yu. M. Cherkashov 《Atomic Energy》2006,100(4):295-301
The basic stages and directions of upgrading and reconstruction of the power-generating units of nuclear power plants with
RBMK reactors over a period of 20 yr since the Chernobyl accident are reflected in this paper. The greatest amount of work
was done in 1986–1990 on all units with RBMK-1000 and-1500 reactors which were operating at that time in the USSR. The purpose
of the upgrade was to improve the neutron-physical characteristics of the reactor cores, increase the response speed of the
safety and control system and decrease the positive effect of water outflow from the cooling loop of this system, increase
the flow capacity of the systems performing emergency discharge of the steam-gas mixture from the reactor, and improve the
basic operating documentation.
The subsequent stages of the upgrading and reconstruction concerned mainly the first-generation power-generating units (Nos.
1 and 2 units of the Leningrad and Kursk nuclear power plants). These works were performed to make the power-generating units
conform to the requirements of the modern normative documents on safety and allow for the possibility of these units to remain
in operation after the nominal 30-yr service life has been exhausted.
__________
Translated from Atomnaya énergiya, Vol. 100, No. 4, pp. 312–320, April, 2006. 相似文献
1000.
The effect of some additives on the equilibrium of valence forms of iron is investigated. It is demonstrated that tin and carbon more significantly than fluorine reduce iron. The redox potential of the glass matrix affects the equilibrium between difference valence forms of iron much less than additives correcting spectral characteristics of glass. 相似文献