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111.
Asiya R. Mustafina Svetlana V. Fedorenko Nelya A. Makarova Ella KH. Kazakova Zul'fiya G. Bazhanova Vladimir E. Kataev Alexander I. Konovalov 《Journal of inclusion phenomena and macrocyclic chemistry》2001,40(1-2):73-76
The inclusion behaviour of a new water-soluble sulfonated calix[4]resorcinarene towards alkylammonium and N-methylpyridinium cations has been investigated on the basis of 1H NMR spectroscopy and pH-potentiometry data. The inclusion of the N-methylpyridinium cation has been found to be dependent on pH with the preferable inclusion of the methyl substituent in alkaline and the aromatic ring in neutral aqueous media. 相似文献
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Jean-Claude G. Bünzli Anne-Sophie Chauvin Hwan Kyu Kim Emmanuel Deiters Svetlana V. Eliseeva 《Coordination chemistry reviews》2010,254(21-22):2623-2633
The photophysical parameters for the sensitization of metal-centred luminescence are analyzed in two series of complexes with tridentate and hexadentate ligands having NxOy chelating units. In particular, the radiative lifetime τrad is experimentally estimated for 29 nine-coordinate EuIII complexes and 10 eight- and nine-coordinate YbIII complexes. The known dependence of τrad on refractive index is substantiated by comparing data for solid-state samples and solutions. Moreover, a clear dependence of τrad with the coordination environment is evidenced and in the case of EuIII, a comparison between τrad and the nephelauxetic effect generated by the ligands is attempted. Altogether, this extensive analysis points to the importance of having a handle on τrad when designing ligands for highly luminescent lanthanide-containing molecular edifices. This, in turn, should stimulate initiating theoretical considerations to unravel a reliable relationship between τrad and the electronic structure of the ligands. 相似文献
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Alexander A. Simenel Galina A. Dokuchaeva Lubov' V. Snegur Alexey N. Rodionov Mikhail M. Ilyin Svetlana I. Zykova Larissa A. Ostrovskaya Natalia V. Bluchterova Margarita M. Fomina Valentina A. Rikova 《应用有机金属化学》2011,25(1):70-75
Ferrocenylalkyl thiopyrimidines ( 6a–d to 9a–d ) were prepared via the reaction of the α‐(hydroxy)alkyl ferrocenes, FcCHR(OH) ( 1a–d ; Fc = ferrocenyl; R = H, Me, Et, Ph), with 2‐thiopyrimidines ( 2 – 5 ) in acetone at room temperature in the presence of TFA, yielding 50–95%. The resulting enantiomers were resolved using HPLC on modified cellulose as chiral selector. The antitumor activities of S‐ferrocenylethyl 2‐thiopyrimidine ( 6b ) against two murine solid tumor models, carcinoma 755 (Ca755) and Lewis lung carcinoma (LLC) were evaluated in vivo. The strong antitumor effect of compound 6b on Ca755 and LLC was demonstrated. The index of tumor growth inhibition on Ca755 equaled 95% in comparison with control. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Semenishchev Vladimir S. Voronina Anna V. Titova Svetlana M. Tomashova Lyubov A. Nasonova Yulia I. 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):857-863
Journal of Radioanalytical and Nuclear Chemistry - Activity concentrations of natural radionuclides were determined in water from 31 springs of Sverdlovsk region, Middle Urals, Russia. Activity... 相似文献
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Svetlana Ignatova David HawesRemco van den Heuvel Peter HewitsonIan A. Sutherland 《Journal of chromatography. A》2010,1217(1):34-39
A new and significantly more robust design of non-synchronous coil planet centrifuge is introduced where the degree of mixing between two immiscible phases can be changed independently from the “g” field required to separate out the phases. A hypothesis that an optimum ratio between the speed of the bobbin and the speed of the rotor can be found to optimise the efficiency of the separation for a given force field is upheld for an intermediate polarity phase system. This paves the way for extensive further research to find the optimum non-synchronous conditions for a range of different phase systems that are desirable for the separation of large molecules, proteins and biologics but can tend to emulsify in the standard “J” type centrifuge systems currently available and routinely in use for aqueous organic phase systems. A step change of up to 30% in resolution and 90% in plate efficiency is demonstrated. 相似文献
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