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131.
Il'yas S. Nizamov Gulnara T. Gabdullina Ilnar D. Nizamov Yevgeniy N. Nikitin Lyubov A. Al'metkina Rafael A. Cherkasov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):732-742
A method of synthesizing arylbisdithiophosphonic acids was developed by the reaction of 2,4-diaryl 1,3,2,4-dithiadiphosphetane-2,4-disulfides with tri(ethylene glycol) and 1,4-butandiol in anhydrous benzene suspension under mild conditions. The arylbisdithiophosphonic acids thus obtained were transformed into the corresponding diammonium salts. New bis(triorganylgermyl), stannyl and plumbyl, and cyclic diphenylsilyl and diphenylplumbyl derivatives of arylbisdithiophosphonic acids were prepared from the reactions of diammonium salts of the corresponding acids with triorganylchlorogermane, chlorostannane, chloroplumbane, diphenyldichlorosilane, and diphenyl dichloroplumbane. 相似文献
132.
Zhipei Yang Kai Zhang Fangbin Gong Shayu Li Jun Chen Jin Shi Ma Lyubov N. Sobenina Albina I. Mikhaleva Boris A. Trofimov Guoqiang Yang 《Journal of photochemistry and photobiology. A, Chemistry》2011,217(1):29-34
A new pyrazole-based fluorescent sensor, 5-amino-3-(5-phenyl-1H-pyrrol-2-yl)-1H-pyrazole-4-carboxamide (compound 1), was studied for fluoride anion (F?) detection in organic or water-containing solution. This compound displayed both changes in UV–vis absorption and fluorescence emission spectra upon addition of F?. With increasing of F?, blue emission intensity increases drastically and reaches saturation with 607-fold enhancement at 424 nm. The results indicate that compound 1 has highly selectivity for fluoride detection over other anions, such as Cl?, Br?, I?, HSO4?, H2PO4? and AcO? in DMSO or aqueous DMSO solutions. 1H NMR titration and other experiments confirm that the sensing process is mainly from the deprotonation of the pyrazole–NH in compound 1. 相似文献
133.
Lyubov N. Sobenina Denis N. TomilinMaxim D. Gotsko Igor A. UshakovAlbina I. Mikhaleva Boris A. Trofimov 《Tetrahedron》2014
(4,5,6,7-Tetrahydroindol-2-yl)alkynes, synthesized by cross-coupling of 4,5,6,7-tetrahydroindoles with aroyl(hetaroyl)bromoalkynes or ethyl bromopropynoate in the presence of K2CO3, regioselectively cyclize with hydroxylamine to either 3- or 5-(4,5,6,7-tetrahydroindol-2-yl)isoxazoles depending on the acidity of the reaction mixture: in the presence of acetic acid 3-isomers are formed (ca. 100% selectivity), while under neutral conditions the reaction is switched to 5-isomers (94–97% selectivity). 相似文献
134.
Selikhov A. N. Lyubov D. M. Mahrova T. V. Cherkasov A. V. Fukin G. K. Trifonov A. A. 《Russian Chemical Bulletin》2020,69(6):1085-1091
Russian Chemical Bulletin - The exchange reactions of equimolar amounts of potassium penta(benzyl)cyclopentadienide CpBn5K (CpBn5 = C5(CH2Ph)5) and SmI2(THF)2 or YCl3 afforded the corresponding... 相似文献
135.
Tatyana S. Zyubina Alexander S. Zyubin Lyubov A. Frolova Rostislav V. Pisarev Anna V. Pisareva Yury A. Dobrovolsky 《中国化学会会志》2023,70(3):432-438
The influence of the composition of oxides supports on the specific electroactive surface area of Pt in the catalysts, the platinum nanoparticles dispersion, and Pt contents in the catalysts was studied. The Sb-doped SnO2 oxides with various Sb-doping levels were prepared as a supports of platinum catalysts in polymer electrolyte membrane fuel cells. Density functional theory simulation of Ti, Sb, and Ru doping of tin dioxide and interaction of the doped surfaces with platinum cluster Pt19 have been carried out. All calculations were performed in PBE exchange–correlation functional, with periodic boundary conditions and projector-augmented waves (PAW) basis set. The calculation results were compared with the experimental data X-ray diffraction and transmission electron microscopy (TEM). It was shown that Sb doping of tin dioxide (in quantity of less than 10%, that is, the quantity which cannot provoke significant defects of crystal structure of the supports) leads to a significant increase in a number of platinum clusters adsorbed from the colloidal solution onto the supports surface which results to an increase of the platinum cluster interaction with the supports. The calculated and experimental results are in close fit. 相似文献
136.
Lyubov Dudareva Vladislav Tarasenko Elena Rudikovskaya 《Photochemistry and photobiology》2020,96(6):1243-1250
The influence of low-intensity laser radiation (LILR) on the changes in the content of anthocyanins, kaempferol, quercetin and their glycosides in the leaves of 5-week-old plants of Arabidopsis thaliana L. was studied by means of methods of high-performance liquid chromatography and gas chromatography mass spectrometry (GC-MS). It was found that in the leaves subjected to a stimulating He-Ne laser radiation dose (3.6 J cm−2, continuous wave radiation, wavelength—632.8 nm, exposure time—5 min), the radiation induced an increase in the content of such compounds, the most significant one being in the case of anthocyanins (9 times). The present study also revealed an increase in the antioxidant potential of kaempferol, quercetin and their glycosides as a result of laser exposure. This increase was due to the preferential synthesis of compounds with a larger number of OH-groups on the phenyl ring. Thus, the content of quercetin, which has five OH-groups in its structure, increased almost by three times as compared to the control. 相似文献
137.
Yatsenko Elena A. Goltsman Boris M. Klimova Lyudmila V. Yatsenko Lyubov A. 《Journal of Thermal Analysis and Calorimetry》2020,141(1):119-130
Journal of Thermal Analysis and Calorimetry - The primary source of the power for marine industry comes from large two-stroke low-speed marine diesel engines. The more severe emission regulations... 相似文献
138.
Il'yas S. Nizamov Gul'nur G. Sergeenko Il'nar D. Nizamov Yan E. Popovich Ravil N. Khaibullin Lyubov A. Al'metkina Boris E. Abalonin Elvira S. Batyeva Dmitry B. Krivolapov Igor A. Litvinov 《Heteroatom Chemistry》2004,15(3):225-232
O-(Trimethylsiloxy)alkyl S-trimethylsilyl aryldithiophosphonates 7a–d were obtained by the reaction of 2,4-diaryl-1,3,2,4-dithiadiphosphetane-2,4-disulfides 5a,b with disilyl derivatives of glycols 6a,c and salicyl alcohol 6b . The reactions of mixed O,S-bis(trimethylsilyl) 2,4-di(3,5-di-tert-butyl-4-hydroxyphenyl)dithiophosphonate 1 and S-silyl aryldithiophosphonates 7a,b with S,S-diethyldithiodiphenylgermane 2 , dichlorodiphenylgermane 8a , and dichlorodiphenylstannane 8b were studied. The structure of hexaphenyl-2,4,6,1,3,5-trithiatrigerminane 11 was established by X-ray single crystal diffraction. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:225–232, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20009 相似文献
139.
Boris L. Erussalimsky Lyubov A. Fedorova Stanislav I. Klenin Lev A. Shibaev 《Macromolecular Symposia》1998,128(1):221-230
Experimental conditions ensuring the formation of living poly(2- and 4-vinyl pyridine) chains in the vinyl pyridine - allyl derivatives of chromium, molybdenum and tungsten systems are described. Variation of the reagents nature, polarity of the solvent permits to obtain polymers differing in their structural and molecular parameters. Synthesized polymers contain block and graft sequences, as well as macrocyclic fragments. Living chains under consideration were applied for polymerization of different monomers. Hybrid polymers obtained by this way were studied in detail by the same methods as the homopolymers. 相似文献
140.
Il'yas S. Nizamov Olga V. Bolshakova Lyubov A. Al'metkina Il'nar D. Nizamov Gulnur G. Sergeenko Liliya V. Frolova Dmitry B. Krivolapov Elvira S. Batyeva Igor A. Litvinov 《Heteroatom Chemistry》2006,17(7):670-675
S‐(Diethylamino)dimethylsilyl bis(diethylamido)dithiophosphate 3 was obtained by the reaction of tetraphosphorus decasulfide 1 with bis(diethylamino)dimethylsilane 2a . The reactions of Lawesson's reagent 5 with 2a and the alkyl homologues of Davy's reagent 8a,b with trimethyl(diethylamino)silane 6 were studied. On the basis of these reactions, methods of synthesizing S‐(diethylamino)dimethylsilyl or S‐(diethylamino)diphenylsilyl 4‐methoxyphenyl (diethylamido)dithiophosphonates 7a and 7b and S‐trimethylsilyl S‐alkyl(diethylamido)trithiophosphates 9a,b are described. The optimal reaction conditions and thermal stability of S‐trimethylsilyl S‐ethyl(diethylamido)trithiophosphate 9a were defined by differential thermal analyses. Compound 9a have been decomposed to form 2,4‐bis(diethylamido)‐1,3,2,4‐dithiadiphosphetane‐2,4‐disulfide 10 which structure was established by X‐ray single crystal diffraction. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:670–675, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20231 相似文献