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101.
The features of the behavior of the diffuse transmission of layers of close-packed titanium dioxide nanoparticles in the visible and near infrared spectral ranges with an increase in the volume fraction f of the particles in a layer have been analyzed. It has been found that an increase in f for layers of small particles (about 25 nm) with a relatively low volume fraction (0.20–0.25) is accompanied by the expected decrease in diffuse transmission. At the same time, an increase in f for layers of large particles (about 100 nm) with a volume fraction of 0.45–0.50 results in a strong increase in transmission. The described phenomenon has been interpreted in terms of the concepts of inverse scattering systems, where the main scattering centers are air nanocavities in a TiO2 matrix rather than TiO2 particles in an air matrix. 相似文献
102.
QCD PERTURBATION THEORY AND NUCLEI (1) THE ENERGY SHIFTS OF HADRENS AND HADRONS MASS DIFFERENCE MASS DIFFERENCE
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QCD perturbation theory for confined quarks and gluons (inhadrons) is discussed.Based on the equivalent potential for the quark-gluon interaction derived, the energyshifts of hadrons and hadron mass difference in MIT bag (cavity) model and correcpond-ing approximation of the w. f. with Gassian form are calculated. 相似文献
103.
In the framework of density functional theory (DFT), the electronic excitations and nonlinear optical (NLO) properties of six binuclear transition metal cluster anions with the formula of [Ch2M-(μ-Ch)2-M'CN]^2- (M = Mo, W; Ch = S, Se; M' = Cu, Ag) have been systemically investigated at both cases of gas phase and DMF solution. The obtained electronic absorption spectra reveal that the element replacements of metals M and ligands Ch have significant influence on the absorptions, especially on the low-lying ones. In addition, the transitions of μ-Ch→M are dominant for the low-lying excitations, whereas the transitions of M'→M as well as Ch→M are mainly responsible for the higher excitations. The calculated molecular first and second hyperpolarizabilities present the remarkable element substitution and solvent effects. The analyses show that the transitions involving μ-Ch→M charge transfer make the critical contributions to the first hyperpolarizability t, and that the charge transfers from the moieties of MCh4 to M'CN as well as those of μ-Ch→M and M'→M are responsible for the second hyperpolarizability y. Moreover, the introduction of solvent leads to the results that the transitions within the moieties of MCh4 and M'CN make larger contributions to the hyperpolarizability, especially to γ. 相似文献
104.
Boundedness criteria for the Hardy–Steklov operator in Lebesgue spaces on the real axis are presented. As applications, two-sided estimates for the norms of spaces associated with weighted Sobolev spaces of the first order with various weight functions and summation parameters are established. 相似文献
105.
P. S. Parfenov A. P. Litvin E. V. Ushakova A. V. Fedorov A. V. Baranov 《Optics and Spectroscopy》2017,122(1):93-95
The morphology of films, superlattices, and other structures of colloidal nanocrystals has been investigated by atomic force microscopy (AFM). The capabilities of ultrasharp and conventional probes for AFM are compared. The problems of detection of nanocrystal close packing are discussed. 相似文献
106.
O. A. Legon’kova T. A. Ushakova I. P. Savchenkova M. S. Belova A. I. Korotaeva A. A. Torkova 《Polymer Science Series D》2018,11(1):86-89
Preparations based on recombinant spidroin protein were studied. A stimulating effect of the studied recombinant proteins on wound repair both in vitro and in vivo was revealed. The greatest positive effect in vivo was observed in the case of the use of MMSC cultures. The optimal period of application of spidroin samples was determined to be the early term of reparation after a trauma or burn. 相似文献
107.
R. L. Ushakova A. I. Mikaya V. G. Zaikin V. I. Kelarev G. A. Shveikhgeimer 《Chemistry of Heterocyclic Compounds》1986,22(4):442-446
1,2,4- and 1,3,4-Oxadiazoles containing indole substituents decompose upon electron impact due to breakage of bonds in the oxadiazole ring. Skeletal rearrangements may occur in the molecular ions of 2,5-diaryl-1,3,4-oxadiazoles due to migration of the aryl groups.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 539–543, April, 1986. 相似文献
108.
Bulgakov R. G. Nevyadovskii E. Yu. Belyaeva A. S. Golikova M. T. Ushakova Z. I. Ponomareva Yu. G. Dzhemilev U. M. Razumovskii S. D. Valyamova F. G. 《Russian Chemical Bulletin》2004,53(1):148-159
Stable ozonolysis products of C60 solutions in CCl4, toluene, and hexane were studied by elemental analysis, HPLC, and UV and IR spectroscopy. Polyketones and esters were established for the first time to be the main stable products, whose content increased during the whole ozonolysis time (1 h). Epoxides C60O
n
(n = 1—6) are accumulated within 1—3 min, and after 5 min of ozonolysis their concentration decreases to zero. Fullerene C60 disappears from the reaction solution due to its conversion to oxides and mechanical capturing of C60 by these oxides to form a precipitate. The oxidation of C60 is completed in the solid phase by the formation of the C60O16 oxide in which 9.68 O atoms fall on fullerene polyketones, 6 O atoms are attributed to esters, and 0.32 O atoms fall per epoxides. The optimum medium for preparation of the C60 oxides is CCl4 rather than traditional toluene, which reacts with ozone in the side reaction to form products containing active oxygen. The C60 cage is raptured during ozonolysis because of the C=C bond cleavage to form two C=O groups at the ends of the open hexagon. Ozonolysis of C60 solutions in CCl4 is efficient for synthesis of water-soluble fullerene oxides due to the high yield and solubility of polyketones and esters in water. 相似文献
109.
V. P. Nekhoroshev N. S. Ushakova A. V. Nekhorosheva S. V. Ruban 《Russian Journal of Applied Chemistry》2005,78(6):931-935
Experimental data on the influence exerted by the synthesis conditions on the composition and properties of a microspherical catalyst for polymerization of propylene are presented. The possibility of using this catalyst for synthesis of noncrystalline propylene polymers is demonstrated.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 6, 2005, pp. 952–956.Original Russian Text Copyright © 2005 by V. Nekhoroshev, Ushakova, A. Nekhorosheva, Ruban. 相似文献
110.
I. D. Konstantinova N. I. Zaitseva I. P. Ushakova G. A. Serebrennikova 《Russian Chemical Bulletin》1994,43(10):1731-1735
A series of cationic ether lipids with short-chain substituents at the 2-position and various cationic groups attached directly or through a spacer group to the glycerol backbone was synthesized.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1826–1830, October, 1994.This work was supported by the Russian Foundation for Basic Research (Project No. 94-03-08-166). 相似文献