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41.
Przerwa E Sosnowski S Slomkowski S 《Langmuir : the ACS journal of surfaces and colloids》2004,20(11):4684-4689
Formation of stripelike assemblies of poly(styrene/alpha-tert-butoxy-omega-vinyl-benzyl-polyglycidol) microspheres adsorbed on nonpatterned mica plates moving perpendicularly from suspension of particles through the water-air interface has been observed. It was found that ordered assemblies were formed by capillary forces acting on particles crossing the water-air boundary. At sufficiently high rates of plate movement (i.e., at appropriate dynamic loading conditions) the adsorbed microspheres approaching the water surface begin sliding on the plate, due to capillary forces, in the direction opposite to the plate movement and are kept below the water surface. Plate movement brings new adsorbed particles to the water-air interface, where particles are assembled into aggregates. When particle aggregates are large, the capillary forces cannot overcome shearing forces and the particle assemblies are withdrawn on the plate above the water surface. This process repeated during continuous movement of the plate results in the formation of the quite regularly distributed stripes of adsorbed microspheres. Formation of the regularly distributed particle assemblies depends on concentration of microspheres in suspension. 相似文献
42.
We present a novel, simple asymptotic expansion for the spectrum of radiation that is backscattered from a laser by a counterpropagating (or copropagating) electron. The solutions are presented in such a way that they explicitly show the relative merit of using an intense laser and of an energetic electron beam in x-ray production in the single particle regime. Simple scaling laws are given. 相似文献
43.
The mechanism and kinetics of energy transfer from highly excited Xe states (E
ex > 9.5 eV), generated by a 12-ns electron beam, to chlorine donor molecules were deduced from time-resolved spectra of fluorescence in the region 240–340 nm. The emissions at 240–250 nm were assigned to Xe2** excimers, and those at 308 and 340 nm to XeCl(B) and XeCl(C) states. Kinetic analysis of the recorded spectra for Xe–CCl4 and Xe–SOCl2 gas mixtures at constant xenon pressure and various pressures of molecular admixtures (0.1–1 Torr) allowed us to find the rate constants for the reactions (5) Xe** + RCI products, (6a) Xe** + RCl XeCl(B) + R*, and (6b) Xe** + RCl XeCl(C) + R*, where R is any radical. 相似文献
44.
The mechanism and kinetics of energy transfer from highly excited Xe states (E
ex > 9.5 eV), generated by a 12-ns electron beam, to chlorine donor molecules were deduced from time-resolved spectra of fluorescence in the region 240–340 nm. The emissions at 240–250 nm were assigned to Xe2** excimers, and those at 308 and 340 nm to XeCl(B) and XeCl(C) states. Kinetic analysis of the recorded spectra for Xe–CCl4 and Xe–SOCl2 gas mixtures at constant xenon pressure and various pressures of molecular admixtures (0.1–1 Torr) allowed us to find the rate constants for the reactions (5) Xe** + RCI products, (6a) Xe** + RCl XeCl(B) + R*, and (6b) Xe** + RCl XeCl(C) + R*, where R is any radical. 相似文献
45.
Leitgeb R Wojtkowski M Kowalczyk A Hitzenberger CK Sticker M Fercher AF 《Optics letters》2000,25(11):820-822
A new method of measurement that essentially combines Fourier-domain optical coherence tomography with spectroscopy is introduced. By use of a windowed Fourier transform it is possible to obtain, in addition to the object structure, spectroscopic information such as the absorption properties of materials. The feasibility of this new method for performing depth-resolved spectroscopy is demonstrated with a glass filter plate. The results are compared with theoretically calculated spectra by use of the well-known spectral characteristics of the light source and the filter plate. 相似文献
46.
P. Kowalczyk Z. Klusek W. Kozlowski P. Byszewski W. Olejniczak 《Applied Physics A: Materials Science & Processing》2007,87(1):37-40
In this paper we present scanning tunneling microscopy/spectroscopy investigations of multiwall carbon nanotube junctions.
We concentrated on bent and narrowing junctions, which my be formed by introducing pentagon–heptagon defects into a hexagonal
network of a carbon nanotube. It was expected that the defects introduced to the nanotube could cause changes in the local
density of states. The scanning tunneling spectroscopy results were used to search for and identify these defects. We also
discuss a hypothesis for a combination of a telescope junction and a pentagon–heptagon induced junction.
PACS 68.37.Ef; 73.22.–f; 61.46.Fg; 71.20.Tx 相似文献
47.
Z. Klusek A. Busiakiewicz R. Schmidt P. Kowalczyk W. Olejniczak 《Surface science》2007,601(6):1513-1520
High-temperature scanning tunnelling microscopy, scanning tunnelling spectroscopy and current imaging tunnelling spectroscopy (HT-STM/STS/CITS) were used to study the topographic and electronic structures changes due to surface modifications of the TiO2(1 1 0) surface caused by the STM tip. In situ high-temperature STM results showed that the created modifications were stable even at elevated temperatures. The STS/CITS results showed the presence of energy gap below the Fermi level on the untreated regions. The disappearance of energy gap below the Fermi level on the modifications created by the tip was observed. It is assumed that the presence of the tip can change the chemical stoichiometry of the surface from TiO2−x towards Ti2O3. 相似文献
48.
49.
We consider a subclass of the class of close-to-convex functions. We show the relationship between our class and the appropriate subordination. Moreover, we give the coefficient estimates and a sufficient condition for functions to belong to the class investigated. Finally, we obtain the distortion and the growth theorems. The results presented are a generalization of the results obtained by Gao and Zhou. 相似文献