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51.
A. R. Mustafina V. G. Shtyrlin L. Ya Zakharova V. V. Skripacheva R. R. Zairov S. E. Solov’eva I. S. Antipin A. I. Konovalov 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):25-32
The effect of the ion-pairing of Co(III) complexes with p-sulfonatothiacalix[4]arene (STCA) on Fe(II)–Co(III) electron transfer rate was evaluated from the analysis and comparison of kinetic data in double Co(III)–Fe(II)
and triple Co(III)–Fe(II)—STCA systems at various concentration conditions. Complexes [Co(en)3]3+(1), [Co(en)2ox]+(2), [Co(dipy)3]3+ (3), [Co(His)2]+(4) and [Fe(CN)6]4− were chosen as Co(III) and Fe(II) compounds. The effect of STCA was found to correlate with the association mode. The outer-sphere association with STCA was found to exhibit the insignificant effect on Fe(II)–Co(III) electron transfer k
et constants for complexes 3 and 4 with bulky and rigid chelate rings, while more sufficient inclusion of flexible ethylendiaminate rings of 1 and 2 into the cavity of STCA results in the unusual increase of k
et. 相似文献
52.
Nataliia S. Kariaka Victor A. Trush Volodymyr V. Medviediev Viktoriya V. Dyakonenko Oleg V. Shishkin Sergii S. Smola 《Journal of Coordination Chemistry》2016,69(1):123-134
Searching for prospective luminescent materials, the series of new lanthanide coordination compounds CsLnL4 (Ln = La, Pr, Nd, Sm – Er, and Yb; L? = {C6H5CONPO(OCH3)2}-) was synthesized. X-ray diffraction studies of CsNdL4 and CsYbL4 have been performed establishing polymeric structures of the tetrakis-complexes built from [LnL4]? anions and cesium cations functioning as linkers. The IR, absorption, emission, excitation spectra, and decay time measurements at 298 and 77 K, as well as thermal gravimetric analyses, were used to characterize the complexes. 相似文献
53.
Valeriy E. Shershov Viktoriya E. Kuznetsova Rinat A. Miftakhov Sergey A. Lapa Andrey A. Stomahin Edward N. Timofeev Irina V. Grechishnikova Alexander S. Zasedatelev Alexander V. Chudinov 《Mendeleev Communications》2021,31(1):70-72
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Viktoriya Ozornova 《代数通讯》2017,45(4):1760-1784
A recent theorem of Dobrinskaya [20] states that the K(π,1)-conjecture holds for an Artin group G if and only if the canonical map BM→BG is a homotopy equivalence, where M denotes the Artin monoid associated to G. The aim of this paper is to give an alternative proof by means of discrete Morse theory and abstract homotopy theory. Moreover, we exhibit a new model for the classifying space of an Artin monoid, in the spirit of [13], and a small chain complex for computing its monoid homology, similar to the one of [44]. 相似文献
56.
Poterya V McLain JL Adams NG Babcock LM 《The journal of physical chemistry. A》2005,109(32):7181-7186
The temperature dependencies of the rate coefficients, alpha(e), for electron-ion dissociative recombination (DR) of N2H+/N2D+ and HCO+/DCO+ ions with electrons have been measured over the range 100-500 K. Also, optical emissions have been detected at approximately 100 K from the N2(B3(pi)g) electronically excited products of N2H+/N2D+ recombination. The measurements were carried out using the classic FALP technique combined with an optical monochromator. For N2H+, there was no variation of alpha(e) with temperature above 200 K, with an average value of alpha(e)(N2H+) = 2.8 x 10(-7) cm3 s(-1). The temperature variation for T approximately 100-300 K observed for alpha(e)(HCO+) is similar to that of N2H+ ions for T approximately 300-500 K. The smaller rate coefficient measured for DCO+ and N2D+ ions shows the influence of an isotope effect. The substantial enhancement of the vibrational level, upsilon' = 6, from the N2B state for N2H+ recombination over N2D+ recombination is consistent with previous result at 300 K and implies the influence of a tunneling mechanism of DR. 相似文献
57.
A. R. Mustafina V. V. Skripacheva A. T. Gubaidullin A. I. Konovalov 《Journal of Structural Chemistry》2005,46(1):S76-S83
Solvation of a calix[4]resorcinarene and its anions in water-organic media of varying composition was characterized by solubility measurements, acid-base titration and X-ray structural analysis. Methanol, 2-propanol, and DMSO capable of developing calix[4]resorcinarene solvated complexes of varying structure and stability were used as the organic component. It was revealed that the influence of the organic component of water-organic solvents on the stability of guest-host complexes formed by some organic and complex cations with calix[4]resorcinarene anions depended on the structure of the complexes. 相似文献
58.
Mustafina AR Skripacheva VV Gubaidullin AT Latipov SK Toropchina AV Yanilkin VV Solovieva SE Antipin IS Konovalov AI 《Inorganic chemistry》2005,44(11):4017-4023
According to the 1H NMR and X-ray data, the outer-sphere association of [Co(dipy)3]3+ with cyclophanic anions p-sulfonatothiacalix[4]arene and tetrasulfonatomethylated calix[4]resorcinarene is accompanied by the inclusion of the dipyridyl moiety of the former into the cavities of the cyclophanic anions in aqueous and aqueous-DMSO solutions and in the solid state. The first-step dissociation of p-sulfonatothiacalix[4]arene does not change the inclusion mode, but the increase in DMSO content leads to a shallower inclusion of [Co(dipy)3]3+. The electrochemical property changes of [Co(dipy)3]3+ with both receptors undergoing ion pairing indicate the stabilization of the tris(dipyridyl) cobalt complexes in lower oxidation states. The effect of the cyclophanic anions on the cyclic voltammograms of [Co(dipy)3]3+ correlates with the efficiency of binding of the latter with tetrasulfonatomethylated calix[4]resorcinarene and p-sulfonatothiacalix[4]arene. 相似文献
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Viktoriya Skripacheva Vladimir Burilov Asiya Mustafina Olga Kataeva Margit Gruner Vitaliy Yanilkin Alexey Stepanov Viktor Syakaev Rustem Zairov Svetlana Soloveva Wolf Habicher Alexander Konovalov 《Journal of inclusion phenomena and macrocyclic chemistry》2011,69(1-2):191-199
The comparative study of the ion-pairing of Co(III) sepulchrate ([Co(sep)]3+) with p-sulfonatothiacalix[4]arene and p-sulfonatocalix[4]arene tetracarbonic acid by 1H NMR and pH-metric data in solution and X-ray data in solid state elucidates pH dependent effect of carboxylate groups on the stoichiometry and the mode of the ion pairing. The electrochemical data of [Co(sep)]3+ bound with both calix[4]arenes have been analyzed in the correlation with stoichiometry and the mode of their binding. The pH-dependent effect of tetracarboxy-p-sulfonatocalix[4]arene on the electrochemical behavior of [Co(sep)]3+ has been found to correlate with the participation of carboxylate groups in the host?Cguest binding. 相似文献