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91.
S. V. Ivanova 《Materials Science》2007,43(5):718-724
We have established that technological defects (cracks) in zirconium articles can develop in the course of long-term storage
prior to their mounting in a reactor, which is caused by the action of residual stresses and hydrogen. We have considered
the conditions of after-operation storage of zirconium articles of the fuel core of thermal reactors in water of the cooling
ponds of reactors and in spent-fuel storehouses. The possibility of subsequent hydrogenation of these articles during their
storage has been shown. Finally, we have studied the effect of hydrogen, absorbed in the course of storage, on the crack resistance
of zirconium articles and the development of defects in them due to delayed hydride cracking.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 105–109, September–October, 2007. 相似文献
92.
Felix Rivkin Irina Kuznetsova Nadezhda Ivanova Sergey Suhodolsky 《Soil Mechanics and Foundation Engineering》2002,39(1):42-43
Soil Mechanics and Foundation Engineering - 相似文献
93.
I. Kh. Akopyan T. I. Ivanova M. É. Labzovskaya B. V. Novikov A. Érdni-Goryaev 《Technical Physics Letters》2010,36(3):240-243
The presence of metastable cubic modifications has been revealed by X-ray diffraction in polycrystalline CdS and CdSe powders with grain sizes on the order of several dozen nanometers. The optical reflection and photoluminescence spectra of the cubic CdS phase have been measured in the temperature interval of 77–295 K. The main exciton transition energies and the temperature coefficients of the bandgap width variation have been determined. 相似文献
94.
N. M. Ivanova 《Journal of Engineering Mathematics》2010,66(1-3):175-180
A generalization of the usual procedure for constructing potential systems for systems of partial differential equations with multidimensional spaces of conservation laws is considered. More precisely, for the construction of potential systems with a multi-dimensional space of local conservation laws, instead of using only basis conservation laws, their arbitrary linear combinations are used that are inequivalent with respect to the equivalence group of the class of systems or symmetry group of the fixed system. It appears that the basis conservation laws can be equivalent with respect to groups of symmetry or equivalence transformations, or vice versa; in this sense the number of independent linear combinations of conservation laws can be grater than the dimension of the space of conservation laws. The first possibility leads to an unnecessary, often cumbersome, investigation of equivalent systems, the second one makes possible that a great number of inequivalent potential systems are missed. Examples of all these possibilities are given. 相似文献
95.
M. Y. Abasov S. F. Gerasimov A. G. Ivanova A. I. Pokhodun O. S. Shulgat 《International Journal of Thermophysics》2010,31(8-9):1663-1675
In CCT documents it is stated that “...for the freezing curves of the metallic fixed points, the maximum observed temperature on the plateau should be taken as the best approximation of the liquidus temperature. The fixed points should be realized with the inner and outer liquid-solid interfaces and extend past the maximum by 10 % to 20 % of the fraction frozen, to clearly establish the value of the maximum and the resolution of its determination.” Also, it is accepted that “...the inner interface is essentially static. It is the temperature of the inner liquid/solid interface that is measured by the thermometer.” The analysis of freezing curves obtained by the standard method of fixed-point realization shows that the parameters of the initial part of the freezing curve, the mean temperature value of which is usually taken as the liquidus temperature, depend on how the inner interface is initiated. Variations in the duration and intensity of initiation cause changes in the initial part of the freezing curve and in the resulting SPRT measurement. Moreover, the relation between the duration of the initial section of the plateau with a minor temperature change and the duration of its final section with a significant slope also depend on the initiation method used and on the furnace temperature. The effect of freezing initiation conditions on the measurement result is individual for each fixed point because of the differences in thermophysical properties of metals and in conditions of the heat transfer from the liquid–solid interface to the thermometer. Aluminum has a maximum value of the melting specific heat in comparison with other metals used in ITS-90 fixed points; in the present study, the effect of the intensity and duration of the inner liquid–solid interface initiation was investigated both experimentally and through calculation. 相似文献
96.
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98.
Thuy Van Lam van Dr. Teodora Ivanova Dr. Kornelia Hardes Miriam Ruth Heindl Dr. Rory E. Morty Prof. Eva Böttcher-Friebertshäuser Prof. Iris Lindberg Dr. Manuel E. Than Dr. Sven O. Dahms Prof. Torsten Steinmetzer 《ChemMedChem》2019,14(6):673-685
The activation of viral glycoproteins by the host protease furin is an essential step in the replication of numerous pathogenic viruses. Thus, effective inhibitors of furin could serve as broad-spectrum antiviral drugs. A crystal structure of an inhibitory hexapeptide derivative in complex with furin served as template for the rational design of various types of new cyclic inhibitors. Most of the prepared derivatives are relatively potent furin inhibitors with inhibition constants in the low nanomolar or even sub-nanomolar range. For seven derivatives the crystal structures in complex with furin could be determined. In three complexes, electron density was found for the entire inhibitor. In the other cases the structures could be determined only for the P6/P5-P1 segments, which directly interact with furin. The cyclic derivatives together with two non-cyclic reference compounds were tested as inhibitors of the proteolytic activation and replication of respiratory syncytial virus in cells. Significant antiviral activity was found for both linear reference inhibitors, whereas a negligible efficacy was determined for the cyclic derivatives. 相似文献
99.
The method of dispersion analysis and experiments are used to establish the possibility of using coal concentration waste, which contains a clay component close to conventional clay raw materials and quartz, calcite and coal impurities. The results of an experimental study of the physicochemical properties of model mixtures are presented together with some practical recommendations. 相似文献
100.
Experimental real-time holograms were recorded on a structure comprising a liquid crystal and a p-i-n-diode based on a hydrogenated amorphous silicon. The holograms offer unprecedented diffraction efficiency at acceptable spatial frequencies. 相似文献