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91.
Sergey V. Paramonov Vladimir Lokshin Artem B. Smolentsev Evgeni M. Glebov Valeri V. Korolev Stepan S. Basok Konstantin A. Lysenko Stéphanie Delbaere Olga A. Fedorova 《Tetrahedron》2012,68(38):7873-7883
Combining a photochromic chromene with a crown ether moiety results in systems in which photochromism and ionophoric properties could significantly influence each other. In this paper, we report the synthesis of several chromenes annelated by 15(18)-crown-5(6) ethers. The approach involves the building of the photochromic fragment upon the initial crown ether via phenols. The two main routes for chromene preparation are discussed. The complex formation of the synthesized photochromic crown-containing naphthopyran with magnesium(II) and barium(II) cations was studied. The kinetic behavior of the colored form of the compound is affected by complex formation. 相似文献
92.
A. L. Stroyuk A. E. Raevskaya A. V. Korzhak I. E. Kotenko E. M. Glebov V. F. Plyusnin S. Ya. Kuchmii 《Theoretical and Experimental Chemistry》2009,45(1):12-22
A relation was established between the composition of Cd
x
Zn1–x
S nanoparticles and their ability to accumulate excess negative charge during irradiation. The rate of expenditure of the
accumulated charge depends on the composition of the nanoparticles and is determined by their electric capacitance. A correlation
was found between the photocatalytic activity of the Cd
x
Zn1–x
S nanoparticles in the release of hydrogen from solutions of Na2SO3, their composition, and their capacity for photoinduced accumulation of excess charge. It was shown that Ni0 nanoparticles photodeposited on the surface of Cd
x
Zn1–x
S are effective cocatalysts for the release of hydrogen. It was found that ZnII additions in photocatalytic systems based on Cd
x
Zn1–x
S/Ni0 nanostructures have a promoting action on the release of hydrogen from water–ethanol mixtures.
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 45, No. 1, pp. 8–16, January-February, 2009. 相似文献
93.
A. L. Stroyuk S. Ya. Kuchmii M. A. Zhukovskii N. P. Smirnova E. M. Glebov V. P. Grivin V. F. Plyusnin 《Theoretical and Experimental Chemistry》2009,45(5):302-307
The properties of TiO2/CdS nanohetero structures produced by the chemical and photocatalytic deposition of CdS nanoparticles on the surface of nanocrystalline
films of TiO2 under the conditions of laser pulse photolysis were studied. It was shown that in the case of photocatalytically formed TiO2/CdS nanocomposites the spatial separation of the photogenerated charges between the components of the hetero structure, leading
to the formation of intermediates of the photochemical transformations (TiIII centers in the TiO2 nanoparticles and S– radical-anions in the CdS nanoparticles), is an order of magnitude more effective. 相似文献
94.
We consider a solution of the nonlinear Klein–Gordon equation perturbed by a parametric driver. The frequency of parametric perturbation varies slowly and passes through a resonant value, which leads to a solution change. We obtain a new connection formula for the asymptotic solution before and after the resonance. 相似文献
95.
We show that photoionization of wide band gap silicate glasses by infrared ultrashort laser pulses can occur without laser-induced
damage. Two glasses are studied, fused silica and a multi-component silicate photo-thermo-refractive (PTR) glass. Experiments
are performed by low numerical aperture focusing of ultrashort laser pulses (100 fsec<τ<1.5 psec) at the wavelengths 780 nm, 1430 nm, and 1550 nm. Filaments form inside both glasses and are visibly observable
due to intrinsic luminescence. Keldysh’s theory of nonlinear photoionization is used to model the formation of filaments and
values of about 1013 W cm−2 for the laser intensity and 1019 cm−3 for the free electron density are estimated for stable filaments to arise. Laser-induced damage is studied by the generation
of a third harmonic from an interface created between a damage site and the surrounding glass matrix. It is found that third
harmonic generation occurs only after several thousands of laser shots indicating that damage is not a single-shot phenomena.
The ability to photoionize PTR glass without damage by ultrashort laser pulses offers a new approach for fabricating diffractive
optical elements in photosensitive glass. 相似文献
96.
Regan SP Delettrez JA Marshall FJ Soures JM Smalyuk VA Yaakobi B Epstein R Glebov VY Jaanimagi PA Meyerhofer DD Radha PB Sangster TC Seka W Skupsky S Stoeckl C Town RP Haynes DA Golovkin IE Hooper CF Frenje JA Li CK Petrasso RD Séguin FH 《Physical review letters》2002,89(8):085003
The Rayleigh-Taylor instability in its highly nonlinear, turbulent stage causes atomic-scale mixing of the shell material with the fuel in the compressed core of inertial-confinement fusion targets. The density of shell material mixed into the outer core of direct-drive plastic-shell spherical-target implosions on the 60-beam, OMEGA laser system is estimated to be 3.4(+/-1.2) g/cm(3) from time-resolved x-ray spectroscopy, charged-particle spectroscopy, and core x-ray images. The estimated fuel density, 3.6(+/-1) g/cm(3), accounts for only approximately 50% of the neutron-burn-averaged electron density, n(e)=2.2(+/-0.4)x10(24) cm(-3). 相似文献
97.
G. A. Kliger O. A. Lesik É. V. Marchevskaya L. S. Glebov S. M. Loktev 《Russian Chemical Bulletin》1986,35(11):2383-2384
Conclusions The hydroammonolysis of the 1-heptyl ester of enanthic acid to 1-heptylamine and di-1-heptylamine was carried out on a fused iron catalyst. Ethers are not aminated under these conditons.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2598–2600, November, 1986. 相似文献
98.
Smalyuk VA Radha PB Delettrez JA Glebov VY Goncharov VN Meyerhofer DD Regan SP Roberts S Sangster TC Soures JM Stoeckl C Frenje JA Li CK Petrasso RD Séguin FH 《Physical review letters》2003,90(13):135002
The temporal history of the target areal-density near peak compression of direct-drive spherical target implosions has been inferred with 14.7-MeV deuterium-helium-3 D3He proton spectroscopy of the 60-beam, 30-kJ UV OMEGA laser system. The target areal-density grows by a factor of approximately 8 during the time of neutron-production ( approximately 400 ps) before reaching 123+/-16 mg/cm(2) at peak compression in the implosion of a 950-micrometer-diam, 20-micrometer-thick plastic CH capsule filled with 4 atm of D3He fuel. 相似文献
99.
High-frequency Bragg gratings in a photothermorefractive glass 总被引:1,自引:0,他引:1
Holographic UV mirrors were recorded in a volume of photothermorefractive glass. This photosensitive silicate glass doped with silver, cerium, and fluorine is transparent in the near-UV, visible, and near-IR spectral regions, and its induced refractive-index change reaches 10(-3). UV radiation of a He-Cd laser at 325 nm was used for Bragg grating recording with a spatial frequency of ~9200 mm(-1). The absolute diffraction efficiency of the recorded mirror reached 12.6% at 325 nm and did not deteriorate under the long-time effects of optical irradiation and heating up 400 degrees C. 相似文献
100.
This paper presents the results of an experimental investigation of the influence of external turbulence on a flow in a rectangular cavity.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 2, pp. 162–166, March–April, 1986. 相似文献