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51.
V. N. Chernik T. N. Smirnova 《Bulletin of the Russian Academy of Sciences: Physics》2014,78(6):489-492
The effect oxygen plasma with energies of 20–30 eV has on a number of materials is studied by simulating their exposure on orbital spacecraft during long duration flights in the ionosphere. The effects of changes in the thermal and optical properties of ECOM-2 black thermoregulation coating and the destruction of the aramid fibers in PRUSMl shielding braid and Scotch 431 protective polyether layer tape that degrade their material properties are described. 相似文献
52.
A. A. Kelyp N. P. Smirnova L. P. Oleksenko L. V. Lutsenko E. I. Oranskaya A. P. Ripko 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(6):1015-1020
The effects of the preparation procedure, active component concentration, and conditions of formation of nanosized cobalt-containing systems based on TiO2 and SiO2 mesoporous powders on their catalytic activity in the oxidation of carbon monoxide were studied. The active phase in the systems was cobalt spinel CoCo2O4 found in all samples. High catalytic activity was found in the samples characterized by relatively high contents of surface active centers (cobalt cations with octahedral surroundings). 相似文献
53.
V. A. Subbotin Yu. V. Kolotilov S. K. Ivashko V. Yu. Smirnova 《Polymer Science Series D》2017,10(3):247-250
Steel failure is closely associated with the aging process, which consists in the diffusion motion of carbon atoms solved in a ferrite matrix to grain boundaries and the release of carbide particles on them. Steel aging is caused by the thermodynamic nonequilibrium of the initial state and the gradual approach to the state of structural equilibrium under conditions of sufficient diffusion mobility of carbon atoms. Aging promotes the initiation and growth of brittle cracks in steel. It is shown that the change in the strength properties of pipe steels in the process of operation calls for the corresponding methods of determining the lifetime of gas pipelines with consideration of the results of diagnostic examinations and the physico-mechanical properties of structural materials used for the construction and repair of gas pipelines. 相似文献
54.
Russian Journal of General Chemistry - The paper focuses on the interaction of two heterocyclic amino acids and hydrophobic benzene with urea, dimethylformamide, and dimethylpropyleneurea in water... 相似文献
55.
V. E. Smirnova E. N. Popova V. M. Svetlichnyi L. A. Myagkova A. N. Orekhov V. E. Yudin A. M. Muzafarov E. A. Tatarinova 《Russian Journal of Applied Chemistry》2011,84(10):1800-1804
The effect exerted by thermal aging in air at 350°C on the thermal and mechanical properties of composite films prepared on
the basis of heat-resistant polyimide PM and non-film-forming polymethylphenylsiloxane (PMPS) was examined. The phase segregation
of polymeric composites of various compositions and the thermal aging rate were evaluated. 相似文献
56.
N. N. Smirnova Yu. A. Zakharova A. V. Markin N. V. Kuchkina E. Yu. Yuzik-Klimova Z. B. Shifrina 《Russian Chemical Bulletin》2013,62(10):2258-2262
The temperature dependences of heat capacity C ○ p = f(T) of hard poly(phenylene-pyridyl) dendrimers of the first and the second generations based on 1,3,5-triethynylbenzene were studied over the temperature range from 7–180 to 455–470 K for the first time. Over the range 290–350 K, the relaxation transition supposedly caused by sample devitrification was detected and characterized for the dendrimer of the first generation. The experimental results were used to calculate the standard thermodynamic functions, namely, heat capacity, enthalpy, entropy, and change in the Gibbs energy on heating. The standard entropy of formation of the compounds under study was determined at T = 298.15 K. The qualitative and quantitative dependences of the thermodynamic properties of the poly(phenylene-pyridyl) dendrimers on their composition and structure were revealed by comparison of the determined parameters with similar data for the earlier studied dendrimers of this series. 相似文献
57.
Natalya N. Smirnova Tatiana G. Kulagina Larisa A. Smirnova Alla E. Mochalova Lyudmila Ya. Tsvetkova Ya. S. Samosudova Maksim B. Kiseliov Evgeny V. Sevast’yanov 《Journal of Thermal Analysis and Calorimetry》2013,112(3):1447-1452
For the first time, the heat capacity $ C_{\text{p}}^{^\circ } $ of poly(2-ethylhexyl acrylate) has been studied in an adiabatic vacuum calorimeter between 7 and 350 K, the standard thermodynamic functions: heat capacity $ C_{\text{p}}^{^\circ } $ (T), enthalpy H°(T) ? H°(0), entropy S°(T) ? S°(0), Gibbs function G°(T) ? H°(0) have been calculated from T → 0 to 350 K. The energy of combustion Δc U of the compound under study has been measured in a calorimeter with a stationary bomb and an isothermal shell. The standard enthalpy of combustion Δc H° and thermodynamic parameters of formation—enthalpy Δf H°, entropy Δf S°, Gibbs function Δf G°—at T = 298.15 K have been calculated. The results have been used to calculate the thermodynamic characteristics of 2-ethylhexyl acrylate bulk polymerization into poly(2-ethylhexyl acrylate) over the range from T → 0 to 350 K. 相似文献
58.
V. I. Pet’kov E. A. Asabina M. V. Sukhanov A. V. Markin N. N. Smirnova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(12):1960-1968
The temperature dependence of the heat capacity C p ○ = f(T) of CaNi0.5Zr1.5(PO4)3 crystalline phosphate is studied by precision adiabatic vacuum and differential scanning calorimetry over the temperature range of 7–640 K. Its standard thermodynamic functions C p ○ (T), H ○(T)-H ○(0), S ○(T), and G ○(T)-H ○(0) for the region T → 0 to 640 K and the standard entropy of formation at T = 298.15 K are calculated from the obtained experimental data. Using data on the low-temperature (30–50 K) heat capacity, the D fractal dimension of phosphate is determined and conclusions about the character of the topology of its structure have been made. The final results are compared to data from thermodynamic investigations of the structurally related crystalline phosphates Zr3(PO4)4, Ni0.5Zr2(PO4)3, and Ca0.5Zr2(PO4)3. 相似文献
59.
D. N. Chausov А. D. Kurilov А. V. Kazak А. I. Smirnova V. К. Velichko E. V. Gevorkyan 《Liquid crystals》2013,40(9):1345-1352
A cholesteric liquid crystal (CLC) – cholesteryl tridecylate (X-20) was doped with nanoparticles of shungite carbon (Sh) to effectively improve some physicochemical properties of the CLC matrix for the further use in electronic devices. The influence of Sh (concentration of 0.005 and 0.02 wt. %) on phase transition temperatures of X-20 was studied. Addition of 0.005 wt. % of Sh shifts phase transition temperatures upward, while the concentration increase to 0.02 wt. % leads to the opposite effect. These data were taken into account during the study of dielectric properties in different phase states. The dielectric properties were studied in the frequency range from 20 Hz to 10 MHz. Only for the system X-20/Sh (0.02 wt. %), dispersion of the dielectric permittivity was observed. The dispersion was caused by the appearance of additional relaxation processes and it was substantially more extended than the classical Debye theory suggests. The results of the research show that the ‘CLC – Sh nanoparticles’ composites can be used as promising materials to increase the efficiency of radio electronics devices. 相似文献
60.
Ionic and Phase Compositions of Y2.5Ce0.5Fe2.5Ga2.5O12 Ferrogarnet Powder Produced by Gel Combustion
Teterin Yu. A. Smirnova M. N. Maslakov K. I. Teterin A. Yu. Kopeva M. A. Nikiforova G. E. Ketsko V. A. 《Doklady Physical Chemistry》2022,503(2):45-49
Doklady Physical Chemistry - The ionic and phase compositions of Y2.5Ce0.5Fe2.5Ga2.5O12 ferrogarnet samples obtained by gel combustion with subsequent vacuum annealing were studied for the first... 相似文献