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1.
We consider a solution of the Cauchy problem u(t, x), t > 0, xR 2, for one class of integro-differential equations. These equations have the following specific feature: the matrix of the coefficients of higher derivatives is degenerate for all x. We establish conditions for the existence of the limit lim t→∞ u(t, x) = v(x) and represent the solution of the Cauchy problem in explicit form in terms of the coefficients of the equation.__________Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 56, No. 12, pp. 1699 – 1706, December, 2004.  相似文献   
2.
Acid–base interaction of holmium(III) and lutecium(III) complexes with octaphenyltetraazaporphyrin in AcOH and AcOH–benzene and AcOH–H2SO4 systems was found to involve one nitrogen meso-atom. Stability constants of the obtained acid forms are determined. Solvoprotolytic dissociation of complexes in the systems based on AcOH is studied and its mechanism is discussed.  相似文献   
3.
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991.  相似文献   
4.
Radiophysics and Quantum Electronics - We estimate geoacoustic parameters of a layered bottom in a shallow waveguide, which is nonuniform along the path, using the data of the full-scale experiment...  相似文献   
5.
Structural Chemistry - Herein we report an X-ray crystallographic characterization of tetramethine merocyanine based on benzimidazole and thiobarbituric acid, which shows negative solvatochromism...  相似文献   
6.
By the reaction of 4-bromphthalonitrile with corresponding 1-phenyl-3-methyl-5-hydroxy- and 1-p-sulfophenyl-3-methyl-5-oxypyrazolaes the substituted phthalonitriles were synthesized and converted into metallophthalocyanines with the fragments of substituted pyrazoles. The compounds obtained were identified using the data of elemental analysis, gas chromatography-mass spectrometry, IR, 1H NMR, and electronic spectroscopy. The influence of the peripheral environment of the phthalocyanine ligand in the resulting metal complexes on the spectral and other properties of the latter was revealed.  相似文献   
7.
We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt[s(NN)]=200 GeV. The spectra were obtained for transverse momenta 0.25相似文献   
8.
On the growth of conversion chromate coatings on 2024-Al alloy   总被引:1,自引:0,他引:1  
The initial growth of chromate conversion coatings on aluminium 2024-T3 alloy has been investigated by scanning Auger microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. The coating initiation is shown to be influenced by the alloy microstructure. In agreement with previously proposed growth models, Cr(VI) to Cr(III) reduction begins on the Al-Cu-Fe-Mn intermetallic second-phase particles, which act as cathodic sites, and then over the entire Al matrix surface. The less noble Al-Cu-Mg second-phase particles demonstrate dual behaviour during the initial stage of coating; some dealloy, with formation of a Cu-rich sponge-like structure, while others show no evidence for etching during the first few seconds and coating deposits on them similar to the situation for the Al-Cu-Fe-Mn particles. XPS measurements show more Cr(III) at the very initial stage of nucleation and growth, whereas the amount of Cr(VI) in the coating increases with the length of the chromating treatment. This is discussed in relation to Raman spectroscopy measurements made in a separate study.  相似文献   
9.
3-Amino-1,1-dichloro-5/6-phenyl-1H-isoindole hydrochloride was reacted with 5-amino-2-imino-3,4-diphenyl-2H-pyrrole or 5-amino-2-imino-3,4-ethylenedithio-2H-pyrrole to obtain unsymmetrical phenyl-substituted porphyrazines.  相似文献   
10.
In this work, diverse hollow nanoparticles of metal oxides and sulfides were prepared by simply laser ablating metal targets in properly chosen liquids. The Kirkendall voiding and the selective heating with an infrared laser were shown to work as two independent mechanisms for the formation of such hollow nanoparticles in only one- or two-step synthesis approaches. One of the prepared materials, ZnS hollow nanoparticles, showed high performance in gas sensing. The simple, fast, inexpensive technique that is proposed demonstrates very promising perspectives.  相似文献   
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