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981.
冷态德士古气化炉流场与停留时间分布的研究 总被引:5,自引:1,他引:5
测定了德士古气化炉的冷态速度分布和停留时间分布。结果表明:德士古气化炉内在轴向2.5~3.0倍直径范围内存在回流,最大回流量为射流量的3.5倍左右;在平均停留时间之前,已有50%左右的物料逸出炉外。本文指出,德士古气化炉中存在的问题,如结渣、耐火砖寿命短、有效气体成分偏低均与炉内流场有关。 相似文献
982.
1,2,2-Trimethyldisilane-1,1,2-triol (1) is formed as an unstable intermediate upon hydrolysis of oligo(trimethyldisilanylsesquiazane). In the absence of trapping
agents it undergoes rapid condensation to give ether-soluble poly(trimethyldisilanyloxane) which contains silanol groups.
Treatment of the hydrolysis products with chlorotrimethylsilane in the presence of triethylamine affords trimethylsiloxy derivatives,
(Me3SiO)2MeSiSiMe2(OSiMe3),5,6, and [Si2Me3O
x
(OSiMe3)
y
]
n
. The isolation of these products indicates that disilanetriol1 readily undergoes condensation to form hydroxylcontaining six-membered rings and polysiloxanes. The condensation of compound1 in the presence of Me3SiOH has been studied. The ratio between the isomeric cyclosiloxanes5 and6 has been determined both by1H NMR spectroscopy and by a chemical method (chlorinolysis).
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1788–1792, October, 1993. 相似文献
983.
We have studied the kinetics of the process of epoxidation of 1-octene by tert-butyl hydroperoxide in the presence of molybdenum boride MoB2. We have studied the effect of the concentrations of starting materials and reaction products on the process. We suggest a kinetic scheme and we calculate the kinetic parameters of the process. 相似文献
984.
985.
The metric in vacuum is found for the case of a spherical charged dust source. It is shown that a dead zone occurs in the vacuum, impenetrable to light or test particles. All singularities resulting from theorems about geodesic lines, are located in the dead zone and do not represent a physical problem for the theory. The infinite-density type singularities may be absent inside matter-filled zone.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 94–99, 1987. 相似文献
986.
N. K. Morozova Yu. A. Pashchenko V. D. Chernyi V. G. Galstyan T. P. Dolukhanyan V. I. Muratova 《Russian Physics Journal》1987,30(2):143-149
The nature of the luminescence of zinc sulfide in the spectral range (360), 380–420 nm (SAL) at 80K is analyzed. It is shown that the appearance of SAL radiation is accompanied by additional absorption in the region (350) 365–370 nm at 80K. The low-temperature spectra of sphalerite, exposed to different radiation and subjected to different treatment, are studied. The multiband luminescence of the isoelectronic sulfur impurity in ZnO deposits in the region 383–640 nm is discussed. It is concluded that SAL luminescence is attributable to the localization of excitons in ZnS on clusters, whose formation precedes the precipitation of the ZnO·S phase. The formation of oxygen clusters and deposits on dislocations in ZnS is studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 60–66, February, 1987. 相似文献
987.
E. Z. Vintaikin V. A. Udovenko S. Yu. Makushev D. F. Litvin 《Russian Physics Journal》1987,30(3):261-265
The method of neutron diffraction is used to construct temperature dependences of the intensity of 110 antiferromagnetic reflection under the influence of compressive stresses = 0–150 MPa along [001]. Application of the stresses leads to an increase in the transition temperature, the transition being delayed in proportion to the increase in the load. On the other hand, the loading leads to a reduction in the magnetization jump for the antiferromagnetic sublattices. Thus, at > 100 MPa, the antiferromagnetic transformation takes on features of a second-order phase transformation. The transition which takes place in the stressed state is characterized by smoother rearrangment of short-order antiferromagnetic order into long-range order, as is evidenced by erosion of the transition boundary. The model proposed here — which does not ascribe the usual effect to uniaxial stresses on the antiferromagnetic transition in -Mn alloys — is based on the anomalous temperature dependence of the elastic constants.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 92–97, March, 1987. 相似文献
988.
Yu. B. Farforovskaya 《Journal of Mathematical Sciences》1987,37(5):1365-1368
Let A be a self-adjoint operator in a Hubert space. In order that for each differentiable function f and for each self-adjoint operator B one should have the estimate f(B)–f(A) cf B–A it is necessary and sufficient that the spectrum. of the operator A be a finite set. If m is the number of points of the spectrum of the operator A, then for the constant cf one can take 8(log2m+2)2 [f], where [f] is the Lipschitz constant of the function f.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 141, pp. 176–182, 1985. 相似文献
989.
S. Yu. Pilyugin 《Journal of Mathematical Sciences》1987,37(3):1149-1153
A compact set K in a smooth closed manifold M is said to be attractive, if on M there exists a system of differential equations, for which K is an asymptotically stable invariant set. It is proved that the set of attractive compacta is dense and its complement contains a dense set of type G in the space of all compacta of the manifold M endowed with two natural topologies.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 143, pp. 170–175, 1985. 相似文献
990.
L. Avanov N. Borodkova Z. NĚmeček A. Omeltchenko J. Šafránková A. Skalski Yu. Yermolaev G. Zastenker 《Czechoslovak Journal of Physics》1987,37(6):759-774
The paper describes the results of investigations of the solar wind ions, carried out on board the high apogee Prognoz 7 and Prognoz 8 Earth's satellites with the aid of an SKS instrument (USSR) and a Monitor instrument (USSR-SSR). Behaviour of proton and that of components on the front of Earth's bow and interplanetary shock waves were compared by means of the energoanalysis and energy-mass analysis techniques. In several long-term periods of observation the solar wind heavy ions — oxygen, silicon and iron were determined. It enabled us to estimate the solar corona chemical composition and electron temperature.Presented at the 5th General Assembly IAGA/IAMAP August 5–17, 1985, Prague, Czechoslovakia. 相似文献