排序方式: 共有27条查询结果,搜索用时 15 毫秒
1.
E. A. Konshina 《Technical Physics》1998,43(9):1062-1068
The results of a determination of the optical breakdown thresholds of air near the surface of copper laser mirrors with a-C:H protective coating by intense pulsed 10.6 μm radiation are analyzed and systematized. It is shown that there is no correlation
between the breakdown threshold of a coated mirror, the reflectance of the coating, and the breakdown threshold of the initial
copper surface. Experimental dependences of the threshold of optical breakdown of coated mirrors on the a-C:H thickness and deposition rate as well as the storage time of the mirrors are given. Estimates are made of the rise in
the surface temperature in the irradiation zone for the case of an ideal adhesive contact and calculations are made of the
damage threshold of the coating in the case that the adhesive contact between the mirror and the coating is impaired. The
effect of the a-C:H coating properties and the conditions at the polished metal surface-protective coating interface on the optical breakdown
threshold is discussed.
Zh. Tekh. Fiz. 68, 59–66 (September 1998) 相似文献
2.
Z. A. Temerdashev Dzh. N. Konshina E. Yu. Logacheva V. V. Konshin 《Journal of Analytical Chemistry》2011,66(10):930-936
A novel thin-layer cellulose adsorbent bearing chemically immobilized thiosemicarbaside is synthesized. The adsorbent is used
for the preconcentration of cobalt(II), mercury(II), and cadmium(II) followed by their X-ray fluorescence quantification in
the concentrate. The physicochemical parameters of metal sorption are determined. 相似文献
3.
The surface structure of thin layers of a-C: H is studied by the method of island decoration, using silver films. The changes in the dimensions and density of silver
particles is tracked by an electron microscope as a function of the thickness of the a-C: H layers. The electrical microprofile is discussed, along with the nature of the silver crystallization centers on the
surface of the a-C: H layers.
Zh. Tekh. Fiz. 68, 108–110 (January 1998) 相似文献
4.
Granular silver films deposited on a thin insulating film of amorphous hydrogenated carbon (a-C:H) and transparent conducting electrode (polycrystalline indium tin oxide (ITO) layer) have been investigated by spectroscopy and microscopy methods. The extinction spectra of silver films on the surface of these materials are found to be significantly different. An annealing of silver films causes a blue shift of the peak of plasmon resonance band in the spectrum of silver nanoparticles: by 16 nm on the a-C:H surface and by 94 nm on the ITO surface. Silver films on the surface of a-C:H films are characterized by a narrower band in the extinction spectrum, which is peaked at 446 nm. The changes observed in the optical density of Ag films are related to the change in size and area of nanoparticles. The results of spectral studies of Ag films are in agreement with the data on the nanostructure obtained by scanning electron microscopy and statistical image processing. The spectra of granular silver films are shown to correlate well with the nanoparticle distribution function over the film area. 相似文献
5.
Dzh. N. Konshina A. V. Danilova Z. A. Temerdashev S. N. Bolotin A. A. Gurinov V. V. Konshin 《Russian Journal of Applied Chemistry》2016,89(4):590-597
A new sorption material, silica gel with covalently immobilized formazan group, was suggested and characterized. The material was prepared by coupling the immobilized aryldiazonium salt with benzaldehyde phenylhydrazone. The equilibrium and kinetic characteristics of the sorption of Cu(II), Co(II), Ni(II), and Cd(II) from solutions onto the modified silica gel were determined. The material proved to efficiently concentrate Cu(II) from multicomponent solutions. The coordination surrounding of Cu(II) in the complex on the sorbent surface was determined by ESR. 相似文献
6.
E. A. Konshina M. A. Fedorov A. E. Rybnikova L. P. Amosova N. L. Ivanova M. V. Isaev D. S. Kostomarov 《Technical Physics》2009,54(4):555-560
The dynamics of the electrooptical 90° twist effect in a dual-frequency nematic liquid crystal is investigated for wavelengths
of 0.65 and 1.55μ m. It is shown that the boundary conditions of the interaction between the phases affect the optical threshold
of the twist effect, the contrast, and the working voltage range. The switching time of the twist effect from the off to the
on state upon a variation of the amplitude of a rectangular dc voltage pulse from 15 to 50 V changes from 1.5 to 0.3 ms for
a thickness of the nematic crystal layer of about 7 μ m. The minimal time of switching from the “on” to the “off” state was
3 ms in the case when relaxation of molecules in a cell with asymmetric boundary conditions was controlled electrically. The
dynamic range of transmittance variation at a wavelength of 1.55 μm extended to 30 dB. 相似文献
7.
A. A. Turmasova V. V. Konshin Dzh. N. Konshina 《Russian Journal of General Chemistry》2014,84(7):1273-1276
Reactions of 1,3-dihydroxyadamantane with 1,3-dicarbonyl compounds in the presence of 5 mol % of In(OTf)3 afforded a series of (1,3-adamantylene)bis-1,3-dicarbonyl compounds in yields of 25–83%. 相似文献
8.
The change in the intensity of the photoluminescence (PL) spectra of nematic liquid crystal (NLC) composites as a function of the concentration of CdSe/ZnS semiconductor quantum dots (QDs) and TiO2 and ZrO2 nanoparticles ~5 nm in diameter has been investigated. It is shown that the PL-quenching intensity in composites with CdSe/ZnS QDs exceeds that in composites with TiO2 and ZrO2 nanoparticles. The lowfrequency spectra of these composites with a concentration of 0.1 wt %, recorded in the range of 102–103 Hz, and the content of mobile ions in them have been investigated. It is found that the dielectric loss in the composite with CdSe/ZnS QDs is much higher and the content of mobile ions is larger by a factor of 3 than in the composites with TiO2 and ZrO2 nanoparticles. It is shown that an increase in the CdSe/ZnS QD concentration in NLC composites leads to an increase in the dielectric loss and a decrease in the PL intensity. Possible mechanisms of the interaction between NLC molecules and CdSe/ZnS QDs are discussed. 相似文献
9.
The dichroic ratio and orientational-order parameter of fundamental bands have been studied in the IR spectrum for a nematic liquid crystal based on alkylcyanobiphenyls and its suspensions with semiconductor CdSe/ZnS QDs with a core size of 5 nm. Analyses have been performed by the method of multiple frustrated total internal reflection. It is shown that an increase in the nanoparticle concentration from 0.5 to 1.3 wt % improves the orientation uniformity of the liquid crystal near the interface with the orienting surface. The orientational order parameter in a suspension with 1.3 wt % QDs has increased in comparison with the initial liquid crystal by more than 10% for the fundamental bands in alkylcyanobiphenyl molecules, the stretching vibrations of which correspond to the direction of their long axes. 相似文献
10.
A. A. Turmasova E. S. Spesivaya Dzh. N. Konshina V. V. Konshin 《Russian Chemical Bulletin》2012,61(9):1733-1735
Reactions of adamantan-1-ol with β-dicarbonyl compounds in 1,2-dichloroethane in the presence of In(OTf)3, Ga(OTf)3, Sc(OTf)3, or Cu(OTf)2 give the corresponding adamantylated derivatives in 45–93% yields. 相似文献