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1.
2.
S. V. Semikolenov K. A. Dubkov E. V. Starokon' D. E. Babushkin G. I. Panov 《Russian Chemical Bulletin》2005,54(4):948-956
The kinetics and mechanism of noncatalytic liquid-phase oxidation of but-1-ene and but-2-ene with nitrous oxide in a benzene
solution in the temperature range from 180 to 240°C were studied. Oxidation proceeds via the 1,3-dipolar cycloaddition mechanism to form carbonyl compounds. Both of these reactions occur with close rates and activation
energies and have the first orders with respect to the alkene and N2O. A considerable fraction (39%) of but-1-ene involved in oxidation undergoes cleavage at the double bond yielding propanal
and an equivalent amount of methylene, the latter producing ethylcyclopropane and cycloheptatriene. The oxidation of but-2-ene
proceeds with a minimum bond cleavage and affords methyl ethyl ketone with 84% selectivity. Regularities of the oxidation
of terminal and internal alkenes C2—C8 with nitrous oxide were analyzed using the previously published data.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 925–933, April, 2005. 相似文献
3.
N. S. Maslova A. I. Oreshkin S. I. Oreshkin V. I. Panov I. V. Radchenko S. V. Savinov 《JETP Letters》2006,84(6):320-323
We report the results of STM investigation of the initial stage of Ag adsorption on an Si(110) surface. At 0.21 ML Ag coverage,
the size and orientation of the unit cell correspond to the parameters of a 16 × 2 unit cell of clean Si(110) surface. With
increasing of the Ag coverage up to 0.42 ML, the type of surface reconstruction changes to a 4 × 1-Si(110)-Ag structure.
The text was submitted by the authors in English. 相似文献
4.
O.G. Kosareva N.A. Panov N. Akozbek V.P. Kandidov Q. Luo S.A. Hosseini W. Liu J.-F. Gravel G. Roy S.L. Chin 《Applied physics. B, Lasers and optics》2006,82(1):111-122
We demonstrate a three orders of magnitude increase and stability in the backscattered fluorescence signal from nitrogen molecules
by terawatt femtosecond laser pulse induced air filaments using a new method. The method is based on squeezing the initial
beam diameter using a telescope. The effect of laser shot-to-shot fluctuations was included in numerical simulations by a
random distribution of the initial intensity in both squeezed and non-squeezed beams. Statistical processing of the simulation
results shows that the average diameter of plasma channels as well as the total amount of free electrons generated in a bunch
of multiple filaments in air is larger in the squeezed beam. Shot-to-shot stability of the simulated plasma density increases
in the squeezed beam. The change of this plasma density with propagation distance is in good qualitative agreement with the
change of the range-corrected nitrogen fluorescence signal with distance.
PACS 42.65.Jx; 42.60.Jf; 42.68.Ay; 42.68.Wt 相似文献
5.
This paper studies isentropic solutions of quasilinear first-order equations with two independent variables and a flux function
that is only continuous. The isentropic solutions are characterized by the requirement that the S. N. Kruzhkov entropy conditions
hold for these solution with the equality sign. It turns out that the existence of a nonconstant isentropic solution imposes
rather strong restrictions on the nonlinearity. In particular, it is shown that on the minimal interval containing the essential
image of the isentropic solution, the flux function satisfies the local Lipschitz condition, and its generalized derivative
is a function of locally bounded variation. Also, it is proved that when the flux function is nonlinear, any isentropic solution
is continuous on nondegenerate intervals.
__________
Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 33, Suzdal
Conference-2004, Part 1, 2005. 相似文献
6.
Dr. Alexey S. Kiryutin Mikhail S. Panov Dr. Alexandra V. Yurkovskaya Prof. Dr. Konstantin L. Ivanov Prof. Dr. Geoffrey Bodenhausen 《Chemphyschem》2019,20(5):766-772
A study of long-lived spin order in chlorothiophene carboxylates at both high and low magnetic fields is presented. Careful sample preparation (removal of dissolved oxygen in solution, chelating of paramagnetic impurities, reduction of convection) allows one to obtain very long-lived singlet order of the two coupled protons in chlorothiophene derivatives, having lifetimes of about 130 s in D2O and 240 s in deuterated methanol, which are much longer than the T1-relaxation times (18 and 30 s, respectively, at a field =9.4 T). In protonated solvents the relaxation times become shorter, but the lifetime is still substantially longer than . In addition, long-lived coherences are shown to have lifetimes as long as 30 s. Thiophene derivatives can be used as molecular tags to study slow transport, slow dynamics and slow chemical processes, as has been shown in recent years. 相似文献
7.
Yu.N. Panov 《European Polymer Journal》1979,15(4):395-397
It has been established that the Newtonian viscosity of solutions of styrene-acrylic acid (4 mol%) copolymers inionomeric form (0–50 mol%) in DMPh is proportional to exp n (n being the degree of neutralization). The principle of temperature-time-concentration superposition is applicable for the dependence of shear modulus on temperature (20–100°), frequency (10?3–1.5 Hz), decree of neutralization (0–50 mol%) and concentration (15–45 g/dl). These facts can be explained in terms of the rheological similarity of physical networks connected with macromolecular chain entanglements and with salt group interactions. Some details of the model for concentrated polymer solutions are discussed. 相似文献
8.
V.G. Kessler A.N. Panov N.Ya. Turova A.Yu. Borissevitch 《Journal of Sol-Gel Science and Technology》1997,8(1-3):1049-1051
The hydrolysis of solutions, containing either LiMo2O4(OPr
i
)5(
i
PrOH) and “La(OPr
i
)3” or LiOPr
i
and La2Mo4O8(OPr
i
)14 in 1∶1 ratio, in toluene or
i
PrOH, by water solutions in isopropanol, leads to formation of monolythic gels. The latter can be converted by drying and
heat treatment at 600°C into a fine powder of pure α-LiLaMo2O8 phase, which is transformed into β-LiLaMo2O8 powder by annealing at 800°C. The sintering of the pellets pressed under 4 bar pressure of α-LiLaMo2O8 powder at 800°C for 2 h converts them into pieces of β-LiLaMo2O8 transparent ceramics, thus providing a route to LiLnMo2O8 laser waveguide materials. 相似文献
9.
E. Kh. Enikeev A. K. Feoktistov M. K. Panov I. M. Krasheninnikova 《Russian Journal of Electrochemistry》2000,36(4):378-386
The composition and structure of layers formed by corrosion products at the open-circuit and passive potentials on the surface
of steel 3 in aqueous media containing sulfate ions, borate ions, or their mixtures are studied by X-ray photoelectron spectroscopy
and secondary ion mass spectrometry. The composition and structure of both the phase surface layers and the adsorption surface
layers are found to depend on the solution nature. The composition and structure of a corrosion product layer; the composition
of the double layer, in particular, the surface charge and potential; and the anion role as a corrosion inhibitor or activator
depend on the way the anion coordinates with the corroding-metal surface. The coordination may be strong, in an inner coordination
sphere (borate ions), or less strong, in an outer coordination sphere (sulfate ions) of a cation on the surface. 相似文献
10.
G. I. Panov G. K. Boreskov A. S. Kharitonov E. M. Moroz 《Reaction Kinetics and Catalysis Letters》1981,16(2-3):247-251
The activity of barium nitride in the isotope exchange of nitrogen is 2–3 orders of magnitude higher than that of Fe and Ru. In the temperature range from 373 to 673 K the activation energy of exchange is 40 kJ/mol.
2–3 Fe Ru. 373–673 40 /.相似文献