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61.
O. V. Borisova M. Yu. Zaremski O. V. Borisov L. Billon 《Polymer Science Series B》2013,55(11-12):573-576
The bootstrap effect is observed in the pseudoliving radical copolymerization of styrene and acrylic acid mediated by a macroinitiator: the adduct of poly(acrylic acid) with a nitroxide radical. In this case, the macroinitiator serves as a peculiar “microreactor” with an increased local concentration of acrylic acid; as a result, the apparent activity of acrylic acid is higher than that in copolymerization mediated by low-molecular-mass initiators. 相似文献
62.
63.
Physicochemical and adsorption properties of hypercross‐linked polystyrene with ultimate cross‐linking density 下载免费PDF全文
Maria P. Tsyurupa Zinaida K. Blinnikova Yuri A. Borisov Mikhail M. Ilyin Tamara P. Klimova Kiril V. Mitsen Vadim A. Davankov 《Journal of separation science》2014,37(7):803-810
The paper describes unexpected properties of hypercross‐linked polystyrenes with ultimate cross‐linking degrees of 300, 400, and 500%, where three, four, or five methylene links, respectively, could bind each polystyrene phenyl ring to its spacious neighbors. The polymers exhibit a strong electron spin resonance signal, unusual spectra in IR, UV, and visible ranges, and they are not typical dielectrics. The nonfunctionalized hypercross‐linked polymers absorb significant amounts of inorganic acids, salts, and bases due to interactions of protons or other cations with electron‐donating fragments of the aromatic network with the high extent of mutual connectivity and also due to dispersion interactions of anions with the polymer matrix. 相似文献
64.
N. N. Andrianova A. M. Borisov Yu. S. Virgiliev E. S. Mashkova A. S. Nemov E. A. Pitirimova A. I. Sorokin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(2):121-126
The temperature dependences (?200°C < T ≤ 350°C) of the ion-induced electron emission yield γ and the structures of modified surface layers have been studied experimentally for SU-850, SU-1000, SU-1300, SU-2000, and SU-2500 glassy carbons under high-dose 30-keV Ar+ and N 2 + ion irradiation. Glassy carbons manufactured using a relatively high heat-treatment temperature T ht exhibit a stepwise increase in the electron yield at certain annealing temperatures T a. The same behavior is observed for graphitized carbon materials. For low-temperature glassy carbons, the electron yield exhibits a monotonic increase with increasing irradiation temperature. The observed differences are related to the occurrence of different structural types of fullerene-like nanoparticles in the low-and high-temperature glassy carbons. 相似文献
65.
Journal of Mathematical Chemistry - We mathematically analyze the solutions to the dynamical system induced by the two-step exponential (growth-)decay (2SED) reaction network involving three... 相似文献
66.
V.?F.?AgekyanEmail author E.?V.?Borisov L.?E.?Vorobjev G.?A.?Melentyev H.?Nyk?nen L.?Riuttanen A.?Yu.?Serov S.?Suihkonen O.?Svensk N.?G.?Filisofov V.?A.?Shalygin L.?A.?Shelukhin 《Physics of the Solid State》2015,57(4):787-793
The optical and electrical properties of silicon-doped epitaxial gallium nitride layers grown on sapphire have been studied. The studies have been performed over a wide range of silicon concentrations on each side of the Mott transition. The critical concentrations of Si atoms corresponding to the formation of an impurity band in gallium nitride (~2.5 × 1018 cm?3) and to the overlap of the impurity band with the conduction band (~2 × 1019 cm?3) have been refined. The maximum of the photoluminescence spectrum shifts nonmonotonically with increasing doping level. This shift is determined by two factors: (1) an increase in the exchange interaction leading to a decrease in the energy gap width and (2) a change in the radiation mechanism as the donor concentration increases. The temperature dependence of the exciton luminescence with participating optical phonons has been studied. The energies of phonon-plasmon modes in GaN: Si layers with different silicon concentrations have been measured using Raman spectroscopy. 相似文献
67.
Dmitri O. Charkin Stanislav I. Bezzubov Oleg I. Siidra Artem S. Borisov Stepan N. Kalmykov 《无机化学与普通化学杂志》2020,646(11-12):540-543
Crystals of a new uranyl sulfate (C2N4H8S2)[UO2(SO4)2] · 0.3H2O ( 1 ) templated by a relatively rare bis-isothiouronium cation, were formed upon evaporation of aqueous solutions containing uranyl acetate, thiourea, and excess sulfuric acid. The new compound is orthorhombic, P212121, a = 6.928(2) Å, b = 13.398(3) Å, c = 15.225(3) Å, Z = 2. Its crystal structure is comprised of [UO2(SO4)2] moieties linked by hydrogen bonds formed between the template cations and terminal oxygen atoms of the sulfate tetrahedra. The C2N4H8S22+ template is most likely formed in situ during a redox reaction between uranyl cation and thiourea in a strongly acidic medium, with UO22+ partially reduced to U4+. 相似文献
68.
Belousov O. V. Ryumin A. I. Belousova N. V. Borisov R. V. Grizan N. V. Lobanova O. N. 《Russian Journal of Applied Chemistry》2020,93(7):1054-1058
Russian Journal of Applied Chemistry - At elevated temperatures (130 and 180°C) in hydrothermal autoclave conditions, the possibility of deep extraction of noble metals from poor intermediate... 相似文献
69.
Matveev D. N. Vasilevskii V. P. Borisov I. L. Volkov V. V. Volkov A. V. 《Russian Journal of Applied Chemistry》2020,93(4):554-563
Russian Journal of Applied Chemistry - The influence of parameters of the dry-jet wet spinning process was studied on properties of porous polysulfone hollow fiber membranes. The air gap distance,... 相似文献
70.
The simple scaling theory of weakly-charged polyelectrolyte brush (the layer of polyelectrolyte chains grafted at one end onto an impermeable surface) immersed into a good solvent has been developed.The asymptotic scaling dependences of the free layer thickness on charge density and solvent strength are obtained. The behavior of polyelectrolyte brush subjected to normal and tangential external forces is considered. New “polyelectrolyte effect” is predicted: shear of a free polyelectrolyte brush leads to a decrease in brush thickness in contrast to the case of a free neutral brush. Such behavior is equivalent to that of a neutral brush subjected to external normal stretching force. This force in the case of polyelectrolyte brush is created by the osmotic pressure of mobile counterions neutralizing grafted chain charges. 相似文献