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I. V. Galkina G. L. Takhautdinova E. V. Tudrii L. M. Yusupova D. B. Krivolapov I. A. Litvinov R. A. Cherkasov V. I. Galkin 《Russian Journal of Organic Chemistry》2013,49(4):598-602
Stable crystalline σ-complexes (Meisenheimer adducts) were isolated for the first time in the reactions of superelectrophilic 4,6-dinitrobenzofuroxan with dodecyl- and hexadecylamines, and their structure was determined by X-ray analysis. 相似文献
84.
R. A. Cherkasov A. R. Garifzyanov R. R. Galeev N. V. Kurnosova R. R. Davletshin S. V. Zakharov 《Russian Journal of General Chemistry》2011,81(7):1464-1469
The processes of membrane transport of ions of scandium(III), samarium(III), gadolinium(III), neodymium(III), aluminum(III),
and a number of alkali and alkaline earth metals through liquid membrane impregnated with aminophosphoryl carriers of different
structures were studied. Selectivity of bis (dialkylphosphinyl)amines towards scandium was found to be significantly higher
than the selectivity of diphosphinylpiperazine and monophosphinylamine in particular. The dependence of transfer efficiency
on the concentration of substrates and carriers was revealed. Optimal conditions for transporting rare and trace metal ions
through the membrane were found, and the mechanism of transmembrane transport was discussed. 相似文献
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Vlasta Závišová Martina KonerackáMarta Mú?ková Jana LazováAlena Juríková Gábor LanczNatália Tomašovi?ová Milan TimkoJozef Ková? Ivo VávraMartin Fabián Artem V. Feoktystov Vasil M. GaramusMikhail V. Avdeev Peter Kop?anský 《Journal of magnetism and magnetic materials》2011,323(10):1408-1412
Poly(ethylene glycol) (PEG)-containing magnetic fluids - magnetite (Fe3O4) stabilized by sodium oleate - were prepared. Magnetic measurements confirmed superparamagnetic behaviour at room temperature. The structure of that kind of magnetic fluid was characterized using different techniques, including electron microscopy, photon cross correlation spectroscopy and small-angle neutron scattering, while the adsorption of PEG on magnetic particles was analyzed by differential scanning calorimetry and Fourier transform infrared spectroscopy. From the in vitro toxicity tests it was found that a magnetic fluid containing PEG (MFPEG) partially inhibited the growth of cancerous B16 cells at the highest tested dose (2.1 mg/ml of Fe3O4 in MFPEG). 相似文献
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Zirconacycles 1, obtained from diethyl 1-alkynylphosphonates, insert either acyl chlorides or nitriles to provide, after acidic workup, (E)-3-oxo-1-alkenylphosphonates, 2, in isolated yields of 55-83%. Insertion produces only one regio- and stereoisomer. The reaction is quite general and proceeds well with both aliphatic and aromatic acyl chlorides. Acetonitrile and p-methoxybenzonitrile also inserted efficiently. Insertion of isobutyl chloroformate produced the vinylphosphonocarboxylate, 2c, the first representative of this class of compounds. 相似文献
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