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Khomich E Kashapov M Vatsouro I Shokova E Kovalev V 《Organic & biomolecular chemistry》2006,4(8):1555-1560
Herein we report on the synthesis and ionophore properties of the first asymmetric p-tert-butylcalix[4]-p-R-thiacalix[4]tubes 7a-c (R = t-Bu, H, 1-adamantyl). The target compounds were obtained by the condensation of tosyloxyethoxy-p-tert-butylcalix[4]arene with the corresponding p-R-thiacalix[4]arenes in the presence of K2CO3 in acetonitrile. The complexation with sodium, potassium and rubidium iodides was studied in CDCl3-CD3OD (4:1) medium by means of 1H NMR measurements. It was found that the ionophore properties of calixtubes 7a-c are controlled by the character of the substituents at the upper rim of the thiacalix[4]arene fragment and it was shown that only the molecular tube 7c with an adamantane-containing thiacalixarene unit is capable of quantitatively binding potassium (swiftly) and rubidium (slowly) cations. 相似文献
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Electrophysical, hydro-gas-dynamic, and thermal characteristics of a discharge arising between liquid electrodes are considered. Spatial visualization of flow patterns in the gas discharge region is performed by using the schlieren technique. 相似文献
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Numerical experiments on the effect of acoustic flows on the structure of a constricted glow discharge in argon have been performed in the hybrid approximation. The possibility of controlling the combustion regime of the glow discharge with an extended positive column at a high pressure by means of the formation of acoustic flows at the excitation of a standing acoustic wave has been demonstrated. In this case, the discharge transfers from the constricted combustion regime to the diffuse one and becomes stable. 相似文献
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E. P. Zhil’tsova R. R. Kashapov L. Ya. Zakharova S. S. Lukashenko A. P. Timosheva E. M. Kasymova A. R. Kayupov A. R. Burilov 《Kinetics and Catalysis》2012,53(2):231-238
The kinetics of phosphorylation of alkylated polyethyleneimine in chloroform in the presence of cationic surfactants with
a cyclic or bicyclic head group and alkylated calix[4]resorcinarenes has been investigated by UV spectrophotometry. The catalytic
activity of individual and mixed solutions of the amphiphilic admixtures depends on the structure of the constituents of the
composition, on their concentrations in the solution, and on their relative amounts. In the presence of a calixarene, a decrease
in the surfactant and polymer concentrations enhances the catalytic effect of the system. 相似文献
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A. Yu. Ziganshina G. R. Nasybullina V. V. Yanilkin N. V. Nastapova D. E. Korshin Yu. S. Spiridonova R. R. Kashapov M. Grüner W. D. Habicher A. A. Karasik A. I. Konovalov 《Russian Journal of Electrochemistry》2014,50(2):142-153
The binding of the amphiphilic 1,5-bis(para-sulfonatophenyl)-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane dianion (APCO2?) with the octacation of the amphiphilic tetramethylviologen calix[4]resorcin having a methyl radical in the resorcinol ring (MVCA-C 1 8+ ) in 30% aqueous DMSO in a 0.1M NaCl supporting solution was studied by various methods. The dianion was bound at the upper rim of calixresorcin due to the donor-acceptor interactions between the viologen acceptor units and the nitrogen- and phosphorus-centered electron-donor fragments of APCO2? and at the lower rim due to hydrophobic interactions. The composition of the complex depended on the MVCA-C 1 8+ : APCO2? ratio. The complexes aggregated, forming insoluble precipitates. MVCA-C 1 8+ -APCO2? is a system with reversibly electro-switchable aggregation. The starting MVCA- 1 8+ octacation partially bound APCO2?, a certain quantity of both substrates remaining in a free state in solution. The MVCA-C 1 4+· tetraradical tetracation formed as a result of the reduction of MVCA-C 1 8+ completely bound APCO2? due to hydrophobic interactions when the MVCA-C 1 8+ : APCO2? ratio was 1: 3. The reversible oxidation of MVCA-C 1 4+· to the starting MVCA-C 1 8+ octacation brought the system back to its starting state 相似文献
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L. Ya. Zakharova T. N. Pashirova R. R. Kashapov E. P. Zhil’tsova N. K. Gaisin O. I. Gnezdilov A. B. Konov S. S. Lukashenko I. M. Magdeev 《Kinetics and Catalysis》2011,52(2):179-185
The catalytic effect of micellar systems based on alkylated 1,4-diazabicyclo[2.2.2]octanes on the alkaline hydrolysis of butyl
chloromethyl 4-nitrophenyl phosphonate is reported. The catalytic effect is due to the reactants concentrating in the micellar
phase. It increases with an increase in the hydrophobicity of the surfactant. The bicyclic surfactant manifests the higher
efficiency than its cyclic and noncyclic analogues. The micellization properties of alkylated 1,4-diazabicyclo[2.2.2]octanes
in aqueous solutions have been investigated by the NMR method. An increase in the hydrophobicity of the surfactant decreases
the critical micelle concentration and increases the hydrodynamic radius and aggregation numbers of the micelles. 相似文献
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A.?B.?MirgorodskayaEmail author S.?S.?Lukashenko R.?A.?Kushnazarova R.?R.?Kashapov L.?Ya.?Zakharova O.?G.?Sinyashin 《Russian Journal of Organic Chemistry》2018,54(7):987-991
A new cationic surfactant containing a butylcarbamate fragment as the head group and hexadecyl radical as hydrophobic component has been synthesized and characterized. Its aggregation paremeters have been determined by tensiometry, conductometry, and dynamic light scattering, and its solubilizing capacity for naphthalene and anthracene has been estimated. 相似文献