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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Sergey V. Avgustinovich Olof Heden Faina I. Solov’eva 《Designs, Codes and Cryptography》2006,39(3):317-322
The main result is that to any even integer q in the interval 0 ≤ q ≤ 2n+1-2log(n+1), there are two perfect codes C1 and C2 of length n = 2m − 1, m ≥ 4, such that |C1 ∩ C2| = q. 相似文献
982.
983.
P. A. Neobyavlyayushchy A. A. Dekterev A. A. Gavrilov Yu. I. Storozhev 《Thermophysics and Aeromechanics》2007,14(1):143-151
A complex numerical and experimental investigation of burner devices for a reburning of the anode gas of aluminum production
was carried out. The chosen mathematical model of the processes of aerodynamics, heat exchange, and gas burning was identified
and adapted on the basis of data of real-scale measurements. Basing on computational experiments the optimization of the design
of elements of the system for anode gas detoxication and transport was carried out. A new system was proposed and tested for
reburning the anode gases of electrolysis production, which consists of an improved burner device and a dust-sedimenting chamber
with a possibility of regulating the amount of gas suction. 相似文献
984.
985.
S.B. Lyubchik L.P. Tikhonova O.L. Galushko I.M. Fonseca 《Applied Surface Science》2006,252(17):6084-6088
Selective adsorption of platinum group metals (PMG) on activated carbons from a multi-component model and technological solutions was proposed for the preparation of heterogeneous-supported catalysts. Activated natural anthracites and a nitrogen-containing synthetic carbon are considered as carriers for Pd-supported catalysts. Their catalytic activity was studied in the Pd-catalyzed reactions of hydrogen peroxide decomposition and chloride ions oxidation by manganese(III). On the base of the obtained results, novel high sensitive analytical methods both for direct determination of supported-metal quantity and palladium oxidation states on the surface of spent adsorbents are suggested. 相似文献
986.
The solution of the problem of magnetic field penetration into a conducting unclosed ellipsoidal sheath in the presence of a conducting thick-walled spherical sheath is reduced to the solution of the integral Fredholm equation of the second kind. The effect of the apex angle of the unclosed ellipsoidal sheath, geometric parameters of the screens, and electrophysical properties of the spherical sheath material on the field attenuation coefficient inside the ellipsoidal sheath is studied numerically. 相似文献
987.
B. Giner I. Gascón A. Villares C. Lafuente 《Journal of Thermal Analysis and Calorimetry》2006,83(3):735-745
The
relation between refractive index deviations and excess volumes for binary
mixtures formed by a cyclic ether and a haloalkane has been tested using several
methods: refractive index mixing rules and equations of state. Refractive
index deviations, excess volumes and molar refractions have been calculated
from experimental data of refractive indices and densities at two temperatures
298.15 and 313.15 K. Results obtained have been discussed in terms of intermolecular
interactions. Refractive indices were compared with those predicted by several
mixing rules. Excess volumes have also been correlated using several cubic
equations of state and finally a relation between parameter b
from equations of state and molar refraction has been provided. 相似文献
988.
Boric acid esters as thermal stabilizers and fungicidal additives for elastomers from natural rubber
New and previously synthesized boric acid esters were studied as thermal stabilizing and fungicidal additives to elastomers based on natural rubbers. 相似文献
989.
E. N. Chebotok V. Yu. Novikov I. N. Konovalova 《Russian Journal of Applied Chemistry》2006,79(7):1162-1166
Depolymerization of chitin and chitosan in the course of deacetylation in an alkaline medium was studied, and the influence exerted on the process by the nature and concentration of the alkali (NaOH, KOH) and salts (NaCl, NaI, KI) was examined. 相似文献
990.
It is suggested to take as pH of the precipitation onset of metal hydroxides the pH at which 10% of the initial amount of metal ions has precipitated. An equation for calculating this quantity is presented. 相似文献