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991.
I A Bukaeva L A Iakovleva B A Lapin L V Indzhiia E M Kobe 《Eksperimental?nai?a onkologii?a》1987,9(4):26-30
The results of morphological study of B- and T-cellular immunoblast baboon lymphomas are presented. Differences are found both in the structure of tumour cells and in the histostructure of tumours as a whole. The tumor cells of B-immunoblastic lymphomas expressed mainly IgM. The tumour cells of certain T-immunoblastic lymphomas being investigated by means of monoclonal OKT4 antibodies had a surface phenotype peculiar to T-helper cells. 相似文献
992.
I A Lisniak 《Eksperimental?nai?a onkologii?a》1987,9(4):72-73
A fraction with the angiogenetic activity was obtained by the methods of the gel-chromatography on G-100 and the ion-exchange chromatography on DEAE-cellulose. Treatment of this fraction with the 10% water isopropanol solution has led to dissociation of the obtained material with a release of a low-molecular-weight angiogenic factor with a high angiogenic activity when tested on the chorioallantoic membrane. The molecular weight of this factor (300-600 daltons) was estimated by the chromatography on the biogel P2. 相似文献
993.
The electrical properties of structures consisting of a monolayer of 1-octadecene deposited on the Si surface are investigated depending on the method of passivation of the surface prior to the deposition of the film (hydrogen and ion passivation) and the intensity of illumination which activates the addition reaction of molecules of 1-octadecene to the Si atoms. The monolayer of 1-octadecene on the Si surface is stable and provides the chemical passivation of the surface. Two types of traps are found, namely, traps for holes and electrons, whose density can be varied during deposition of the monolayer by the choice of intensity of illumination and by the method of passivation of the surface. In the case of a low level of illumination and/or the use of the iodine passivation of the surface, the electron traps prevail, and, in the case of high intensity of illumination and/or hydrogen passivation of the surface, the hole traps prevail. It is shown that the use of these films provides conductivity in thin near-surface layers of Si due to providing the mode of flat bands or accumulation of carriers near the surface. 相似文献
994.
I. V. Khomskaya V. I. Zel’dovich N. Yu. Frolova 《Metal Science and Heat Treatment》2007,49(3-4):118-124
The strain behavior and phase transformations in Cu-37 wt.% Zn brass, Cu-12.5 wt.% Al bronze, and copper (99.97%) are studied
under two variants of pulse loading, i.e., converging shock waves and a flux of powder particles accelerated by explosion.
The effects connected with uniform and localized strain caused by the action of shock waves are determined and the disperse
structures formed in the materials under dynamic loading are analyzed.
__________
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 3, pp. 28–34, March, 2007. 相似文献
995.
996.
V. I. Naryshkin G. M. Strelkov A. M. Ryazantsev 《Journal of Communications Technology and Electronics》2008,53(7):782-787
Deformation and attenuation of an ultrawideband radio pulse propagating along a single-wire line are analyzed as functions of the pulse initial duration. Variations in the longitudinal and transverse components of the pulse electric field with the distance from the line are determined. Features of the spatial distribution of the energy carried by the pulse near the line are revealed. 相似文献
997.
The infiltration of compacted cubic BN (cBN) with molten aluminum has been investigated as a potential route for a cheap and easy method of manufacturing cBN/metal composites. CBN compacts have been infiltrated with molten Al at a temperature between 670 and 800 °C and pressure of 15 MPa in vacuum. At these temperatures no pronounced interactions between hexagonal and cubic BN with Al was observed, allowing the complete infiltration of cBN with 12 μm mean grain size. After infiltration at 800 °C, the temperature was increased without pressure to convert aluminum into borides and AlN. The hardness of the resulting materials depends on the content of hexagonal, cubic BN and the rate of conversion of Al into borides and AlN. The infiltration height of less than 1 mm obtained from infiltrating the 3 μm cBN powder green compacts gave a hardness of 22.0 ± 0.6 GPa after heat treatment. 相似文献
998.
I. Egli L. Davidsson M.-A. Juillerat D. Barclay R. Hurrell 《Journal of food science》2003,68(5):1855-1859
Complementary foods based on cereals and legumes often contain high amounts of phytic acid, a potent inhibitor of mineral and trace element absorption. The possibility to degrade phytic acid during the production of complementary foods by using whole grain cereals as the phytase source was investigated. Whole grain rye, wheat, or buckwheat (10%) were added to cereal‐legume‐based complementary food mixtures, and phytic acid was shown to be completely degraded in a relatively short time (1.5 to 3 h) when incubated at optimal conditions for cereal phytase. The potential usefulness of the method for industrial production was demonstrated with a complementary food based on wheat and soybean. 相似文献
999.
D. D. Avrov S. I. Dorozhkin Yu. M. Tairov A. Yu. Fadeev A. O. Lebedev 《Semiconductors》2008,42(13):1469-1474
The problem of the appearance of carbon inclusions in single-crystal silicon carbide ingots grown by the modified Lely method (the so-called graphitization of the ingot) is analyzed. It is shown that the process of graphitization of the ingot is not related to a deficit of silicon in the growth cell; in contrast, it is excess of silicon at the growth surface that inhibits the ingot growth rate and gives rise to intense corrosion of the graphite fittings. 相似文献
1000.
I. N. Ishchuk 《Measurement Techniques》2007,50(10):1081-1086
A three-dimensional solution of the direct problem of heat conduction when a linear pulsed heat source acts in the plane of
contact of two semibounded bodies is presented. The solution is obtained by the method of finite differences. An example of
the modeling is considered.
__________
Translated from Izmeritel’naya Tekhnika, No. 10, pp. 42–45, October, 2007. 相似文献