排序方式: 共有32条查询结果,搜索用时 15 毫秒
11.
The role of water vapor in benzaldehyde photolysis and photonucleation is investigated experimentally as well as with the help of semiempirical estimation of reaction intermediates. It is shown that water molecules act as a clustering agent that brings together two benzaldehyde molecules. This mechanism may explain the experimental observation of glyoxal formation during photolysis in humid carrier gas even in the presence of oxygen, the dependence of the concentrations of glyoxal and diphenyl on water-vapor concentration, and some other unusual facts concerning minor products detected in the experiment. 相似文献
12.
E. S. Dubtsov 《Journal of Mathematical Sciences》2008,148(6):841-845
Let u be a strictly positive, harmonic Bloch function on the upper half-space ℝ
+
d+1
. Then the set
has the maximal Hausdorff dimension. Bibliography: 7 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 345, 2007, pp. 105–112. 相似文献
13.
A. V. Dubtsov S. V. Pasechnik D. V. Shmeliova D. A. Semerenko Aleš Iglič Samo Kralj 《Liquid crystals》2018,45(3):388-400
We report the study of optical textures and director configurations within nematic-in-water microdroplets of the liquid-crystalline mixtures based on azoxybenzene and cyanobiphenyl (as a polar dopant). Both pure azoxybenzene and polar dopant materials exhibited bipolar configuration within liquid-crystalline droplets, whereas their mixtures at appropriate concentrations spontaneously formed radial droplets. It was found that increasing of the dopant’s concentration resulted in the forward tangential-homeotropic and reentrant homeotropic-tangential anchoring transitions. We also triggered bipolar-to-radial structural transition by UV irradiation providing trans-cis isomerisation of nematogens. Critical irradiation time needed for radial configuration formation was found to decrease with concentration of polar dopant. Mesoscoping modelling is proposed to explain main experimental results. The presented data are discussed for chemical and biological sensing applications. 相似文献
14.
E. S. Dubtsov 《Siberian Mathematical Journal》2009,50(6):998-1006
Denote by Hol(B
n
) the space of all holomorphic functions in the unit ball B
n
of ℂ
n
, n ≥ 1. Given g ∈ Hol(B
m
) and a holomorphic mapping φ: B
m
→ B
n
, put C
φ
g
f = g · (f ∘ φ) for f ∈ Hol(B
n
). We characterize those g and φ for which C
φ
g
is a bounded (or compact) operator from the growth space A
−log(B
n
) or A
−β
(B
n
), β > 0, to the weighted Bergman space A
α
p
(B
m
), 0 < p < ∞, α > −1. We obtain some generalizations of these results and study related integral operators. 相似文献
15.
Imre Salma Willy Maenhaut Sergei Dubtsov va Zempln-Papp Gyula Zray 《Microchemical Journal》2000,67(1-3)
As part of an air pollution study in Budapest, size-fractionated aerosol samples were collected by stacked filter units and cascade impactors, and some criteria pollutants and meteorological parameters were recorded in 1996, 1998 and 1999. The samplings were performed at three urban locations including an urban background site, a downtown site, and a tunnel. Elemental composition of the aerosol samples was measured by instrumental neutron activation analysis and/or particle-induced X-ray emission spectrometry; and black carbon (BC) was determined by a light reflectance technique. Since leaded gasoline was completely phased out in Hungary on 1 April 1999, the atmospheric concentrations of some typical transportation-related air pollutants (i.e. Pb, Br, BC and CO) were used for overviewing the actual impact of the phase out on the air quality and on the aerosol characteristics. For the background site, mean concentration of Pb and Br was not changed significantly. In the downtown site, the phase out resulted in a concentration decrease by a factor of 3–4 for Pb and Br. For the tunnel, concentrations of Pb and Br were decreased by a factor up to 9 and 28, respectively. Correlation between the pollutants, their crustal enrichment factors, and average elemental mass size distributions are also presented and discussed. 相似文献
16.
E. S. Dubtsov 《Journal of Mathematical Sciences》2007,141(5):1531-1537
Let
and τ denote the invariant gradient and invariant measure on the unit ball B of ℂn, respectively. Assume that f is a holomorphic function on B and ϕ ∈ C2(ℝ) is a nonnegative, nondecreasing, convex function. Then f belongs to the Hardy-Orlicz space H
ϕ(B>) if and only if
Analogous characterizations of Bergman-Orlicz spaces are obtained. Bibliography: 9 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 333, 2006, pp. 43–53. 相似文献
17.
S. V. Pasechnik D. V. Shmeliova A. V. Dubtsov V. G. Chigrinov Jiatong Sun 《Molecular Crystals and Liquid Crystals》2015,611(1):81-93
The modified method for shear viscosity measurements of nematic liquid crystals (NLC) oriented by surfaces is described. The main modification is concerned with usage of photoalignment technique for preparation of mono-domain samples with an orientation controlled by a polarization state of the secondary light irradiation. It provides the azimuthal rotation of a sample at any desirable angle. Thus different geometries of shear flows can be realized after filling the measuring cell with a liquid crystal. The method is experimentally approved at investigation of Poiseuille decay flows of 4-pentyl-4-cyanobiphenyl (5CB) through the channels with a rectangular cross section. The proposed construction of the cell with different surface treatment provides measurements of the three principal viscosities coefficients (Miesowicz’ viscosities) with additional usage of electric field. A small amount (less than 0.2 ml) of a liquid crystal needed for measurements and simple measuring procedure makes the method to be useful for rheological studies of newly synthesised liquid crystal materials. 相似文献
18.
Ki Hwan Bae 《中国化学快报》2009,20(11):1321-1323
Phytochemical study on the BuOH-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of a new salicin derivative(1),named davidianoside.The structure was elucidated on the basis of extensive physicochemical and spectroscopic analyses. 相似文献
19.
Sodium dialkyl phosphite reacts with non-activated alkyl halide in the presence of crown ether to give dialkyl alkyl phosphonate in moderate yield. Little or no reaction takes place in the absence of crown ether under the same conditions. In all cases, crown ether was present in catalytic amts. indicating that it behaves as a phase transfer catalyst between solid and liquid phases. The influences of structures of crown ethers, alkyl halides, dialkyl phosphites and the nature of solvent on the P-alkylation of sodium dialkyl phosphite have been investigated. 相似文献
20.
S. M. Shandarov N. I. Burimov M. A. Dubtsov V. G. Sibagatulina D. S. Baklanov Yu. N. Kulchin R. V. Romashko Yu. F. Kargin A. V. Egorysheva V. V. Volkov 《Laser Physics》2007,17(4):482-490
The polarization structure of the signal wave that interacts with a circularly polarized pump wave on the reflection holographic gratings in the (112)-, (111)-, and (110)-cut Bi12TiO20 (BTO) crystals is experimentally and theoretically analyzed. An analytical expression for the vector field of the signal wave that is valid for an arbitrary orientation of the cubic refractive crystal is derived using approximation of the nondepleting circularly polarized pump wave. The contribution of the absorption component of the reflection hologram into the counter interaction is estimated for the crystals under study using the approximation of the experimental data with theoretical curves. Based on the experiments with incoherent quasi-monochromatic radiation, it is demonstrated that the real BTO crystals exhibit weak induced linear birefringence. 相似文献