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161.
162.
Conditions for the oscillation of all solutions and for the existence of nonoscillatory solutions with polynomial growth at infinity are given for the system of differential-functional equations of neutral type
相似文献
163.
164.
V. S. Reznik V. S. Bakulin Yu. S. Shvetsov B. E. Ivanov 《Russian Chemical Bulletin》1975,24(6):1290-1293
Conclusions Some esters of -(oxodihydro-N-pyrimidinyl)butyl- and -(oxodihydro-N-pyrimidinyi)pentylphosphonic acids, and also some diphenyl -(2,4-dioxo-6-methyl-1,2,3,4-tetrahydro-N-pyrimidinyl)alkyl phosphates, were synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1397–1401, June, 1975. 相似文献
165.
The Pd/ZrO2 and Pd/SO4/ZrO2 systems were investigated by diffuse-reflectance IR spectroscopy using CO as the probe molecule. For the Pd/ZrO2 system, the behavior of the metal is characteristic of the weak metal-support interaction. Intense bands attibuted to the bridging CO species indicate the formation of large metal particles in the reduced systems. Modification of the ZrO2 support with SO4 2? anions leads to an increase in the metal—support interaction and makes the metal more resistant to reduction. On the surface promoted by SO4 2? anions, metal particles with a positive charge (Pd+ and Pdδ+) were observed. The smaller the size of the metal clusters and the higher degree of oxidation of sulfur, the stronger the influence of acidic protons and surface sulfur compounds on the metal. 相似文献
166.
The homotopic method has been used to analyze the kinetic models of CO oxidation on two surface patches conjugated by COads spillover. On each patch reaction proceeds via a three-stage mechanism but with different constants. The stability of steady-states solution has been studied. COads spillover from one patch to another changes substantially the bifurcation picture of steady states and produces islands. 相似文献
167.
The oxidation of cumene and a cumene-nitrobenzene (12) mixture at 60°C in the presence of AIBN and acetylacetonates of Co(II), Cu(II), Fe(II), Fe(III), V(III), Cr(III), Mn(III) and MoO
2
2+
has been investigated.
(12) 60°C - Co(II), Cu(II), Fe(II), Fe(III), V(III), Cr(III), Mn(III), MoO 2 +2 .相似文献 168.
A. V. Ivanov A. S. Zaeva E. V. Novikova T. A. Rodina W. Forsling 《Russian Journal of Inorganic Chemistry》2007,52(5):691-697
Crystalline adducts of zinc and copper(II) dithiocarbamate (Dtc) complexes with dialkylamines [M(NHR′2)(S2CNR2)2] (M = Zn, 63Cu, 65Cu; R = CH3, C2H5, or R2 = (CH2)4O; R′ = C2H5, C3H7) have been preparatively isolated. The structures and spectral properties of the adducts have been studied by EPR and 13C and 15N MAS NMR. Chemisorption of bases on powders of dinuclear dithiocarbamates leads to their dissociation into monomeric adducts. Computer simulation demonstrates that the experimental EPR spectra of isotope-substituted copper(II) adducts have an individual character. The geometry of the copper polyhedra is intermediate between a trigonal bipyramid (TBP) and a tetragonal pyramid (TP). The TBP and TP contributions have been quantified based on EPR data. 13C and 15N MAS NMR data show that the Dtc ligands incorporated into the zinc adduct molecule are structurally nonequivalent. The dependence of the isotropic 15N chemical shifts of the Dtc groups on the alkyl substituents at the nitrogen atom is interpreted based on the concept of joint manifestation of the (+)inductive effect of the alkyl substituents and the mesomeric effect of the Dtc groups. 相似文献
169.
The coagulation ability of humic acids (HAs) obtained from mechanically activated high-moor peat has been investigated. The effects of the concentration and the methods of isolation of HAs from peat on the reversible aggregation of blood erythrocytes have been studied. The strength of aggregates of erythrocytes and the period of their aggregation have been found to depend on the concentration and composition of HAs. 相似文献
170.
The synthesis has been effected of the amide of the tetrapeptide forming the sequence 6–9 of oxytocin with the use of benzyl protection of the thiol function of cysteine by two main schemes 1+3 and 2+2. The advantageousness of performing the synthesis by the 2+2 scheme has been shown. The overall yield of tetrapeptide using the method of condensation with the formation of mixed anhydrides amounted to 51% by the scheme proposed.All-Union Scientific-Research Institute of the Technology of Blood Substitutes and Hormone Preparations, Moscow. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 393–400, May–August, 1992. 相似文献
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