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51.
Intra‐ and inter‐supramolecular complexation of poly(butyl methacrylate)‐co‐2‐(1,2,3‐triazol‐4‐yl)pyridine copolymers induced by CoII,FeII, and EuIII ions monitored by molecular hydrodynamics methods 下载免费PDF全文
Georges M. Pavlov Igor Perevyazko Bobby Happ Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2016,54(16):2632-2639
Poly(butyl methacrylate) copolymers embedding bidentate 2‐(1,2,3‐triazol‐4‐yl)pyridine (trzpy) chelating units as comonomer in the side chains were synthesized by controlled radical addition‐fragmentation transfer (RAFT) polymerization. Intracomplexation and intercomplexation of the macromolecules of the poly(butyl methacrylate) copolymers containing 20 % mol of trzpy units induced by CoII, FeII, and EuIII ions were studied in the solutions by macromolecular hydrodynamics methods. The sedimentation velocity of extremely diluted copolymer solutions and the dynamic viscosity of moderately diluted solutions were studied in a wide range of the salts concentrations. Differences were observed with respect to the copolymer behavior in the presence of the Co2+, Fe2+, Eu3+ ions. These differences are namely due to the differences in the number of coordination bonds required for complex formation and not explicitly to the nature of the corresponding anions. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2632–2639 相似文献
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V. V. Grubov E. Yu. Sitnikova A. A. Koronovskii A. N. Pavlov A. E. Hramov 《Bulletin of the Russian Academy of Sciences: Physics》2012,76(12):1361-1364
The time-frequency structure and dynamics of oscillatory patterns in electroencephalograms of rats is studied by means of continuous wavelet transform and the decomposition of the signal by empirical modes. A method for the automatic selection of patterns using the empirical modes is developed. The method is applied to the study of sleep spindles, and it is shown that their dynamics depends on the regularities of on-off intermittency. 相似文献
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Bulyarskiy S. V. Zenova E. V. Lakalin A. V. Molodenskii M. S. Pavlov A. A. Tagachenkov A. M. Terent’ev A. V. 《Technical Physics》2018,63(12):1834-1839
Technical Physics - The formation of nanoparticles of a thin-film nickel catalyst applied on a buffer layer in the form of pure titanium, titanium oxide, or titanium nitride has been studied. It... 相似文献
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V. A. Pavlov F. R. Sagitova V. V. Moskva 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The fomation of monomeric metaphosphate has been postulated before, mainly i pyrolytic [1,2] or photolytic [3] fragmentation reactions. Meantime, these reactive intermediats are presumed to participate in the processes of electrophilic phosphorylation in living organisms [4]. In this connection it is reasonable that an active interest is being shown in the development of methods of generating metaphosphates in mild conditions [4–7] compatible with biological systems in order to simulate biological phosphoryl-transfer reactions. 相似文献
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Information regarding the metabolism of xenobiotic chemicals plays a central role in regulatory risk assessments. In regulatory programmes where metabolism studies are required, the studies of metabolic pathways are often incomplete and the identification of activated metabolites and important degradation products are limited by analytical methods. Because so many more new chemicals are being produced than can be assessed for potential hazards, setting assessment priorities among the thousands of untested chemicals requires methods for predictive hazard identification which can be derived directly from chemical structure and their likely metabolites. In a series of papers we are sharing our experience in the computerized management of metabolic data and the development of simulators of metabolism for predicting the environmental fate and (eco)toxicity of chemicals. The first paper of the series presents a knowledge-based formalism for the computer simulation of non-intermediary metabolism for untested chemicals, with an emphasis on qualitative and quantitative aspects of modelling metabolism. 相似文献
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The reaction of 2-aminothiazoles with ethyl acetoacetate in acetic or polyphosphoric acid gave a series of 5H-[1,3]thiazolo[3,2-a]pyrimidin-5-one derivatives which were nitrated with a mixture of nitric and sulfuric acid to 6-nitro-5H-[1,3]thiazolo[3,2-a]pyrimidin-5-ones, and the latter were reduced to the corresponding amines. 相似文献
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A. V. Voronin A. E. Aleksandrov B. Ya. Ber P. N. Brunkov A. A. Bormatov V. K. Gusev E. V. Demina A. N. Novokhatskii S. I. Pavlov M. D. Prusakova G. Yu. Sotnikova M. A. Yagovkina 《Technical Physics》2016,61(3):370-376
We report on experimental results on multiple action of hydrogen, deuterium, and helium plasmas produced by a plasma gun and the Globus-M tokamak on tungsten. The surface temperature in the course of irradiation is measured with a bichromatic pyrometer with a time resolution of ?1 μs. The morphology of the surface layer is investigated and X-ray structure analysis of tungsten exposed to multiple radiations by the plasma under various conditions is carried out. A slight decrease in the lattice parameter in the sample subjected to the maximal number of irradiation cycles is detected. It is shown that the morphology of the tungsten surface irradiated by the hydrogen plasma from the gun and by the deuterium plasma from the Globus-M tokamak changes (the structure becomes smoother). The characteristic depth of the layer in which impurities have been accumulated exceeds 0.5 μm. This depth was the largest for the sample exposed to 1000 shots from the gun and 2370 shots from the tokamak. It is shown that the helium jet from the plasma gun makes it possible to simulate the action of helium ions on the International Thermonuclear Experimental Reactor (ITER) diverter, producing a layer of submicrometer particles (bubbles). 相似文献