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1.
New phosphorylated 1,2,4-triazole-3-thiones have been synthesized, and the possibility of their N,Sfunctionalization has been demonstrated. The direction of alkylation of 1,2,4-triazole-3-thiones with ethyl acrylate has been shown to depend on the substituent on the N4 atom.  相似文献   
2.
S-Methyl diethylphosphinothioate reacted with benzylidene chlorides to give the corresponding aryl(chloro)methyl methyl sulfide and diethylphosphinoyl chloride. The product structure suggests initial attack of the methylsulfanyl group on the CH carbon atom of dichloromethylarene. Arenecarbothialdehyde dithioacetals and trimers and O,O-dialkyl[aryl(methylsulfanyl)methyl]phosphonates were synthesized.  相似文献   
3.
4.
Lead zirconate titanate (PZT) films doped with lanthanum, Pb(1–х)Laх(Zr0.48Ti0.52) (х = 0, 0.02, 0.05, 0.08, or 0.01), have been investigated by electron microscopy and X-ray diffraction. Films were formed on Si–SiO2–TiO2–Pt substrates by chemical vapor deposition from a solution and annealed at temperatures T = 650 and 750°C. The main structural features of the films, differing them from undoped PZT films fabricated by the same method, have been established. It is found that doping with lanthanum delays the pyrochlore–perovskite transformation in the film bulk, i.e., in the regions distant from the film–substrate interface. The fraction of metastable pyrochlore phase increases with an increase in the La molar content in the films. The main reason for the delay is the deficit of lead in the intergranular perovskite space, especially in the upper part of the film. Annealing at T = 750°C reduces the content of pyrochlore phase but does not completely remove it, which was never observed for undoped PZT films. Doping with lanthanum leads to a change in the lattice period c and a tetragonal distortion of the perovskite lattice (c/a ratio). Hence, the [100] texture of the films obtained, in contrast to the typical [111] texture of PZT films, is due to the increase in the lattice mismatch between the film and platinum layer when lead atoms are replaced with lanthanum. Lattice distortions of “transrotational” character, whose value exceeds 160 deg/μm, are found to arise in growing crystals.  相似文献   
5.
Thiosemicarbazides of diphenylphosphorylacetic acid and their cyclic derivatives have been synthesized. Functionalization of the obtained 1,2,4-triazole-3-thiones with ethyl 2-bromoacetate at the sulfur atom has been carried out, the obtained esters have been transformed into the corresponding hydrazides via hydrazinolysis. Preliminary pharmacological tests of the synthesized compounds have been performed.  相似文献   
6.
By reactions of N-alkyl- and N-arylimidazoles with methyl 12-bromoacetyldehydroabietate a series of unsymmetrically substituted chiral imidazolium bromides with the abietane fragment was synthesized. The salts obtained were suggested as new N-heterocyclic carbene ligands in the Suzuki-Miyaura reaction.  相似文献   
7.
Efficient methods and algorithms have been developed for the optimization of catalytic processes and reactors. In mathematical terms, these problems reduce to finding the extremum of a functional of a large number of variables whose domain of variation is subject to various constraints as sets of partial differential equations and algebraic inequalities. This implies solving problems in which the domain of extremals is closed. Applying Pontryagin's maximum principle to catalytic processes described by sets of differential equations with constrained phase and control variables allows the necessary set of optimal conditions to be found. A numerical algorithm has been developed for solving nonlinear boundary-value problems that arise when the maximum principle is employed. The efficiency of this algorithm is demonstrated by the example of the catalytic oligomerization of α-methylstyrene, a typical process requiring various kinds of optimization problems to be solved. The theoretical optimization of the process has served as the basis for the engineering optimization of an industrial reactor. Optimal controls were determined in both the theoretical and engineering optimization steps.  相似文献   
8.
Russian Journal of General Chemistry - The molecular and crystal structures of 8-(3,6-diphenylpyridin-2-yl)-5,7-dimethoxy-4-phenyl-2H-chromen-2-one,...  相似文献   
9.
Russian Chemical Bulletin - The main route of a new reaction of (dichloromethyl)arenes with S-methyl diethylthiophosphinate is the attack of the thiol sulfur atom (P–SMe) on the methylene...  相似文献   
10.
Russian Journal of General Chemistry - О-Methyl diethylphosphinothioate reacts with benzylidene chlorides to form arenecarbthioaldehyde trimers and diethylphosphinoyl chloride. This result...  相似文献   
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