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1.
V. A. Yanchenko A. M. Demchenko M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2004,40(4):516-518
We propose a method for obtaining derivatives of 7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine by alkylation of 4-amino-5-methyl-4H-1,2,4-triazole-3-thiol by substituted -chloroacetanilides, followed by cyclization of the intermediate by phosphorus oxychloride. 相似文献
2.
Mathematical Notes - An Erratum to this paper has been published: https://doi.org/10.1134/S0001434621070300 相似文献
3.
A. M. Demchenko V. A. Yanchenko V. V. Kisly M. S. Lozinskii 《Chemistry of Heterocyclic Compounds》2005,41(5):668-672
We have developed a method for synthesis of aryl isothiocyanates by means of thiocarbamoylation of aromatic amines by tetramethylthiuram disulfide followed by degradation of the intermediate N(1)-aryl-N,N-dimethylthiourea by concentrated HCl. We have shown that thiocarbamoylation of 4-amino-5-ethyl-4H-1,2,4-triazole-3-thiol occurs at the 2 position of the triazole ring, while thiocarbamoylation of 4-amino-3-methyl-6-phenyl-4,5-dihydro-1,2,4-triazin-5-one leads to the dihetaryl-substituted thiourea. We consider the possibility of using N(1)-aryl-N,N-dimethylthioureas as analogs of isothiocyanates in reactions with N-nucleophiles.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 775–780, May, 2005. 相似文献
4.
Kovaleva E. G. Molochnikov L. S. Kharchuk V. G. Kuznetsova O. V. Shishmakov A. B. Yanchenko M. Yu. Buldakova L. Yu. Zhdanov I. N. Mikushina Yu. V. Petrov L. A. 《Kinetics and Catalysis》2004,45(5):752-758
The distribution of Cu2+ ions in ZrO2 and sulfated ZrO2 hydrogel phases was studied by EPR spectroscopy and voltammetry. The formation of the following three types of copper structures was observed: mononuclear Cu2+ complexes (A), magnetic associates (B), and Cu2+ compounds (C) that gave no EPR signals under the conditions used in the spectroscopic measurements. The specific catalytic activity of various Cu2+ compounds in the liquid-phase reaction of 2,3,5-trimethyl-1,4-hydroquinone oxidation was determined. The copper complexes C were found to exhibit the highest catalytic activity. 相似文献
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We prove the existence of infinite subgroups with nontrivial locally finite radicals and of locally finite subgroups in the groups with almost finite almost solvable elements of prime orders and in the groups with generally finite elements. 相似文献
7.
We prove the existence of infinite subgroups with nontrivial locally finite radicals and of infinite locally finite subgroups in the groups with almost finite almost solvable elements of order 2 and 4 and in the groups with almost finite elements. 相似文献
8.
Anna K. Yanchenko Graham Tierney Joseph Lawson Christoph Hellmayr Andrew Cron Mike West 《商业与工业应用随机模型》2023,39(3):292-309
Forecasting enterprise-wide revenue is critical to many companies and presents several challenges and opportunities for significant business impact. This case study is based on model developments to address these challenges for forecasting in a large-scale retail company. Focused on multivariate revenue forecasting across collections of supermarkets and product categories, hierarchical dynamic models are natural: these are able to couple revenue streams in an integrated forecasting model, while allowing conditional decoupling to enable relevant and sensitive analysis together with scalable computation. Structured models exploit multi-scale modeling to cascade information on price and promotion activities as predictors relevant across categories and groups of stores. With a context-relevant focus on forecasting revenue 12 weeks ahead, the study highlights product categories that benefit from multi-scale information, defines insights into when, how, and why multivariate models improve forecast accuracy, and shows how cross-category dependencies can relate to promotion decisions in one category impacting others. Bayesian modeling developments underlying the case study are accessible in custom code for interested readers. 相似文献
9.
V.?M.?Za?nullina V.?P.?Zhukov V.?N.?Krasil’nikov M.?Yu.?Yanchenko L.?Yu.?Buldakova E.?V.?Polyakov 《Physics of the Solid State》2010,52(2):271-280
The electronic structures of undoped anatase and anatase doped with carbon and vanadium have been calculated using the ab
initio tight-binding linear muffin-tin orbital (TB-LMTO) method in the LSDA + U approximation. It has been shown that the
doping of TiO2 leads to the formation of narrow bands of the C and Vimpurity states in the band gap. The calculations of the imaginary part
of the dielectric function have made it possible to estimate the intensity of the optical absorption. It has been established
that the doping with vanadium and carbon leads to optical absorption in the visible range and to an increase in the absorption
in the ultraviolet range up to 4 eV. This should result in an increase in the photocatalytic activity on the surface of the
doped anatase. The experimental determination of the photocatalytic activity of whiskers of the anatase doped with carbon
and vanadium in the reaction of hydroquinone oxidation has confirmed the increase in the activity of the doped materials under
exposure to ultraviolet, visible, and blue light. The phenomenon of dark catalysis in the anatase doped with carbon and vanadium
has been interpreted within the concept of low-energy electronic excitatio ns between the impurity levels of carbon. 相似文献
10.
Ukrainian Mathematical Journal - We establish the exact-order estimates for the approximation of the classes $$ {S}_{1,\theta}^rB\left({\mathrm{\mathbb{R}}}^d\right) $$ by entire functions of... 相似文献