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排序方式: 共有10000条查询结果,搜索用时 14 毫秒
991.
992.
993.
A convenient and high yielding preparation of 2,6-di-t-butyl-1,4-benzoquinone from the iron-catalyzed oxidation of 2,4,6-tri-t-butylphenol with t-butyl hydroperoxide (TBHP) under acidic conditions is reported. 相似文献
994.
A. T. D’yachenko K. A. Gridnev 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(7):857-861
A hydrodynamic approach to describing heavy-ion collisions with allowance for the emission of the secondary particles is developed. The compression, the expansion, and break-up stages of the resulting hotspot are considered. The formed shock wave has a time-dependent front. The calculated spectra of produced protons are compared with experimental data. 相似文献
995.
996.
P. Yu. Grigor’ev E. E. Zhurkin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2012,6(2):229-235
The self-sputtering processes of (111) Si and Al surfaces under bombardment by Si
N
and Al
N
ions and clusters (N = 1−60) with the same energy per particle-projectile atom (1 keV/atom) are studied in this paper. The nonlinear effects produced
in the target during the development stage of an atomic-collision cascade and during the postcascade stage are analyzed, and
a correlation between these effects and secondary emission characteristics is found. The study has been carried out in the
framework of classical molecular dynamics. As a result, a number of features of (111) Si and Al surface sputtering and erosion
have been revealed. Thus, it has been established that the sputtering yield increases nonadditively as the size N of the implanted cluster increases at N > 10, which is related to the appearance of nonlinear cascades and the postcascade heat spike, and is accompanied by microcrater
formation. It is shown that the implantation of clusters into the Si target leads to the formation of amorphous regions. 相似文献
997.
B. I. Bairachnyi A. A. Fedorenko G. G. Tul’skii O. N. Borsuk B. B. Bairachnyi 《Russian Journal of Applied Chemistry》2013,86(7):1001-1005
Development directions of the sulfate method for manufacture of titanium dioxide are considered, and alternative solutions for improving its cost efficiency and ecological advisability are suggested. A high-efficiency technology for electrochemical synthesis of a strong reducing agent, Ti2(SO4)3·nH2O, used instead of waste iron and powdered aluminum is suggested. 相似文献
998.
A. R. Gataulina A. A. Khannanov O. A. Malinovskikh O. V. Bondar’ N. A. Ulakhovich M. P. Kutyreva 《Russian Journal of General Chemistry》2013,83(12):2269-2271
The third generation hyperbranched polyesterpolyol has been modified with maleic anhydride at various ratios of the polyol to the modifying agent, from 1: 6 to 1: 18. The prepared modified polyols are capable of the complex formation with copper(II), cobalt(II), and nickel(II) ions. 相似文献
999.
L. G. Rogozhina M. V. Kuz’min N. I. Kol’tsov 《Russian Journal of Applied Chemistry》2013,86(4):581-586
A procedure was developed for preparing cyanourethane laquer compositions based on polyisocyanates, polyesters of various structures, and dicyanodiamide. The influence of the polyester structure and component ratio on the properties of the cured laquer coatings was examined, and the compositions allowing preparation of corrosion- and heat-resistant laquer coatings were determined. 相似文献
1000.