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51.
Three-component condensation of primary amines with carbon disulfide and dialkyl maleates afforded the corresponding alkyl (3-R-4-oxo-2-sulfanylidene-1,3-thiazolidin-5-yl)acetates whose structure was confirmed by independent synthesis and IR and 1H NMR spectroscopy.  相似文献   
52.
The results of the investigation of radiation-thermal hydrodesulphurization of brown coal in presence of methane under accelerated electrons with a dose rate P=350 Gy/s in the intervals of temperatureT=200–500 °C, absorbed dose up to 60 kGy are presented. It has been established that at the more favourable conditions (T=400–450 °C,D>60 kGy) about 80% of sulphur is removed from the coal and in the solid product sulphur decreased up to 1.0–1.1%. In these conditions the selectivity of desulphurization processes iss=2.6–3.8 and energy consumption towards removal of sulphur isE=0.5–0.6 kW h/kg. The mechanism of selective activation by irradiation for the desulphurization process is discussed.  相似文献   
53.
Four polyelectrolyte (PE)-protein and PE-peptide systems were selected for fluorescence experiments. The mode of binding of proteins to PE and structure of forming polycomplexes depends upon the ratio of components and chemical composition of polymer macromolecules. Complex formation of proteins with oppositely charged polycations is realized by the self-assembly of non-stoichiometric polycomplex particles with characteristic composition. These polycomplex particles have a rigid rod-like carcass structures in which protein molecules are practically exposed to the solvent. Two types of ternary polyanion-Cu2+-protein polycomplex particles are formed depending on the monomer composition of the copolymer. At higher content of hydrophobic N-isopropylacrylamide monomer unites, the protein globules in the structure of ternary polycomplex particles are densely covered by the shell of a polymer coil and practically “fenced of” from the water environment. At higher content of acrylic acid unites, polycomplex particles have more friable structures in which protein molecules are practically exposed to the solution. The PE-peptide conjugate species can be represented rather as a macromolecule of a segmented (block) copolymer in which the hydrophobic blocks, i.e. the sequences of copolymer and peptide unit pairs, which have formed the covalent and salt bonds alternate with hydrophilic ones, i.e. the sequences of the copolymer chain not participating in the formation of double strand blocks.  相似文献   
54.
The energy spectra of fast electrons resulting from pair collisions between metastable atoms and from collisions of the second kind with electrons are observed in the afterglow of a helium-filled microplasma collisional electron spectroscopy (CES) detector at a pressure of 5?C40 Torr. It is demonstrated that impurities present in the main inert gas can be detected and their composition can be determined using a planar double-electrode detector in which the cathode simultaneously serves as an analyzer of electrons in the afterglow.  相似文献   
55.
Reactions of acyloxyalkyl chloride with alkaline salts of alkylxanthic, butyltrithiocarbonic, and diethyldithiocarbamic acids afforded a series of acyloxyalkyl esters of various nature and positions of the acyl groups in the molecule.  相似文献   
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The shrinkage of vacuum-molded thermoplastics is investigated together with its dependence on molding temperature and pressure and dwell time in the mold. It is shown that the dependence of the shrinkage on these parameters is qualitatively the same for all three materials investigated.Mekhanika Polimerov, Vol. 4, No. 1, pp. 178–180, 1968  相似文献   
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Let A be a complex Banach algebra with identity and let a A be a Hermitian element. An interpolation formula is proved expressing sin a in terms of exponentials. This formula implies, in particular, the identity sin a = |sin a|. Bibliography: 6 titles.  相似文献   
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