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991.
The results from a thermodynamic analysis of high-octane gasoline component production from catalytic cracking gases using zeolite catalyst OMNIKAT-210P modified with Ni, Co, Cr are presented. The equilibrium constants of the reactions assumed to occur in this process are calculated, along with the equilibrium yield of the reactions.  相似文献   
992.
Pyridine catalyzes oxidation of alcohols with 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxyl–iodine catalytic system at room temperature. Symmetric esters are formed in good yields.  相似文献   
993.
We consider the properties of the positiveness, fractional power, boundedness, and separation of the singular Sturm-Liouville operator in a weighted space depending on the behavior of its coefficients. We derive necessary and sufficient conditions for its positiveness, trace class property, boundedness, and separation.  相似文献   
994.
S. Sh. Mousavi 《代数通讯》2020,48(8):3184-3203
Abstract

In category theory, the existence of free objects is very important, especially free modules that play an important role in homological algebra. Although algebraic hyperstructures are a natural extension of algebraic structures, due to the major difference between them, study-free objects in algebraic hyperstructures become very difficult. In this article, we provide a categorical approach for the construction of free hypermodules. In fact, by considering appropriate morphisms between hypermodules, we characterize free hypermodules from three different perspectives.  相似文献   
995.
996.
New thiacalix[4]arenes tetrasubstituted by terpyridyl fragments at the lower rims in the 1,3-alternate stereoisomeric form were synthesized. The molecules interact with EuIII and TbIII in the DMF solution to form highly luminescent nanoscale (21–26 nm) metal-organic structures with the 2: 1 metal-to-ligand stoichiometry and a narrow particle size distribution.  相似文献   
997.
Colloid Journal - Equations have been derived for the size dependence of the interfacial tension and contact angle of a small spherical sessile bubble under isothermal conditions. It has been shown...  相似文献   
998.
Journal of Experimental and Theoretical Physics - A model is developed to study a hard/soft magnetic bilayer in an external magnetic field by the Monte Carlo method. The influence of the constants...  相似文献   
999.
Lithium-vanadium oxide with the formal composition Li6V5O15, uniform microsctructure, and the particle size of 100 nm is synthesized by a solution method. The synthesized compound is characterized by the methods of X-ray diffraction analysis, Raman spectroscopy, and synchronous thermal analysis. The total electric conductivity is measured by the method of impedance spectroscopy and its electronic component is estimated by dc method. In the temperature range of 200–400°C, Li6V5O15 represents a mixed electronic- ionic conductor with predomination of the ionic component and is thermally stable up to 550°С. Preliminary tests of a laboratory model of electrochemical cell Li|LiPF6|Li6V5O15 are carried out.  相似文献   
1000.
The platinum(II) and palladium(II) complexes [Pt6(SCH2CH2NH2)8]Cl4 and [Pd6(SCH2CH2OH)8 Cl4· 5H2O with mercamine and β-mercaptoethanol, respectively, were synthesized. It was found on the basis of the comparison of IR and X-ray electron spectra of the ligands and complexes, and also of the data of X-ray diffraction analysis that the bidentate coordination of ligands through sulfur and nitrogen atoms is realized in the platinum(II) complex. In the palladium(II) complex β-mercaptoethanol is coordinated in a mixed-mode type. In both complexes sulfur atoms of the ligands occupy a bridging position.  相似文献   
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