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101.
Lavrent’ev K. K. Sabirov R. L. Chizhov S. A. Yashin V. E. 《Optics and Spectroscopy》2000,89(1):150-154
A repetitively pulsed solid-state laser system with a new version of a pulse compression scheme based on stimulated Brillouin scattering is proposed. The scheme allows us to work in a wide energy range from 100 mJ to several Joules, with a compressed pulse as short as 150–300 ps.
相似文献102.
Savelyeva N. Yu. Shpirt A. M. Orlova A. V. Chizhov A. O. Kononov L. O. 《Russian Chemical Bulletin》2022,71(8):1784-1793
Russian Chemical Bulletin - Using the CuI-catalyzed 1,3-dipolar cycloaddition of terminal alkynes to azides, neuraminic acid di-, tri-, and tetrapseudosaccharides were synthesized, in which... 相似文献
103.
A method is developed of synthesis of (tetrabenzoporphyrinato)chloromanganese(III) from tetrabenzoporphyrinatocadmium( II)
(as a donor of the macrocyclic ligand) and the salts, manganese acetate MnAc2 and dichloromanganese MnCl2, in boiling dimethylformamide
in the presence of atmosperic oxygen in 80% yield. It is found that under the conditions of the synthesis tetrabenzoporphyrinatomanganese(II)
is formed which can be oxidized by the atmospheric oxygen to (tetrabenzoporphyrinato)chloromanganese(III). Absorption spectra
in the visible and infrared regions, R
f
and the data of elemental analysis characterizing the resulting compound are given. 相似文献
104.
I. V. Chizhov 《Moscow University Computational Mathematics and Cybernetics》2009,33(3):151-157
The McEliece-Sidel’nikov cryptosystem is a modification of the McEliece cryptosystem, which is one of the oldest public-key
cryptosystems. It was proposed by V.M. Sidel’nikov in 1994 and is based on the u-fold application of Reed-Muller codes RM(r, m). The lower bound is obtained for the power of the set of public keys of the McEliece-Sidel’nikov cryptosystem using an arbitrary
number of blocks (u). 相似文献
105.
NL Asfandiarov AI Fokin VG Lukin EP Nafikova GS Lomakin VS Fal'ko YV Chizhov 《Rapid communications in mass spectrometry : RCM》1999,13(12):1116-1123
A series of anthraquinone (C(14)O(2)H(8)) derivatives has been studied by means of electron capture negative ion mass spectrometry (ECNI-MS), photoelectron spectroscopy (PES), and AM1 quantum chemical calculations. Mean lifetimes of molecular negative ions M(-.) (MNI) have been measured. The mechanism of long-lived MNI formation in the epithermal energy region of incident electrons has been investigated. A simple model of a molecule (a spherical potential well with the repulsive centrifugal term) has been applied for the analysis of the energy dependence of cross sections at the first stage of the electron capture process. It has been shown that a temporary resonance of MNI at the energy approximately 0.5 eV corresponds to a shape resonance with lifetime 1-2.10(-13) s in the f-partial wave (l = 3) of the incident electron. The next resonant state of MNI at the energy approximately 1.7 eV has been associated with the electron excited Feshbach resonance (whose parent state is a triplet npi* transition). In all cases the initial electron state of the MNI relaxes into the ground state by means of a radiationless transition, and the final state of the MNI is a nuclear excited resonance with a lifetime measurable on the mass spectrometry timescale. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
106.
WYETH Paul 《中国科学:化学》2010,(3)
Silks represent some of the most precious ancient and historic textile artefacts in collections worldwide.Their optimum preservation demands an appreciation of their characteristics.One important concern,especially with regard to ancient Chinese silks,is whether the fabrics have been degummed.Silks with remnant sericin gum coating the fibroin fibres would require different conservation protocol.In previous research on aged silks,the presence of sericin has been inferred from amino acid analysis of hydrolysa... 相似文献
107.
A. S. Rozenberg E. I. Aleksandrova G. I. Dzhardimalieva N. V. Kir'yakov P. E. Chizhov V. I. Petinov A. D. Pomogailo 《Russian Chemical Bulletin》1995,44(5):858-866
Thermal transformations (at 340 to 390 °C) of coprecipitates of iron and cobalt acrylates, [Fe3O(CH2CHCOO)6OH][Co(CH2CHCOO)2]2.4 (1) and [Fe3O(CH2CHCOO)6OH][Co(CH2CHCOO)2]1.5·3H2O (2), are studied. The dependence of the degree of gas evolution () on time is described by the equation () wherek
1=2.3 · 1012 · exp[–49500/(RT)] s–1,k
2=6.0 · 106 · exp[–33000/(RT)] s–1 andk
1=2.6 · 1012 · exp[–49000/(RT)] s–1,k
2=6.6 · 105 · exp[–30000/(RT)] s–1 for cocrystallizates1 and2, respectively. The coefficient 1 decreases as the temperature increases. The value of 1 for compound1 is higher than that for compound2. The composition of products of the transformations of1 and2 are studied. The main solid state products of the decomposition are nanometer-sized particles of cobalt ferrite, CoFe2O4, with a narrow size distribution stabilized by the polymeric matrix. The thermal transformations of cocrystallizates1 and2 include dehydration, thermal decomposition, copolymerization in the solid state, and decarboxylation of the metallocarboxylate groups of the polymer. The effect of the ratio between the Fe clusters and the Co-containing fragments on the process of thermal transformation is analyzed.For Part 40, seeRuss. Chem. Bull., 1994,43, 2020.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 885–893, May, 1995.The authors are grateful to A. N. Titkov for optical microscopic and electron microscopic studies. 相似文献
108.
Oleg S. Chizhov Valentin I. Kadentsev Andrei A. Stomakhin 《Journal of mass spectrometry : JMS》1991,26(9):757-760
Chemical ionization mass spectra of halogenoalkanes (RX) obtained using tetramethylsilane as reagent gas show two major peaks corresponding to the cluster ion RX+SiMe3 and alkyl ion R+. Iodides exhibit the highest affinity toward the trimethylsilyl ion and produce the most stable silylated molecular ions, whereas bromides and especially chlorides are less reactive toward Me3Si+ ions and form less stable [M + SiMe3]+ ions. 相似文献
109.
Two compounds — the diethylamides of 1,2-dimethyl-3-carbethoxy-6-carboxyfuro[2,3-f]- and 1,2-dimethyl-3-carbethoxy-5-carboxvfuro[3,2-e]indoles — are formed in the reaction of 1,2-dimethyl-3-carbethoxy-5-hydroxyacetic acid (I) with dimethylformamide and phosphorus oxychloride as a result of subsequent intramolecular cyclization of the intermediates. This constitutes evidence for formylation of the starting acid in the 6 and 4 positions. Formylation of the ethyl ester of acid I gives only the 6-formyl derivative, the intramolecular cyclization of which under the influence of sodium ethoxide gives 1,2-dimethyl-3,6-dicarbethoxyfuro[2,3-f]-indole. Hydrolysis of the latter with alcoholic alkali gives the corresponding dicarboxylic acid. The structures of the synthesized compounds were confirmed by the PMR, IR, and mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 766–769, June, 1977. 相似文献
110.
In the weakly relativistic limit, an expression is obtained for the damping of quasistationary energy levels in Schwarzschild and Kerr fields due to capture by a collapsar. The strength of the damping in the Schwarzschild field decreases strongly with increasing angular momentum of the particle. If the condition < mH is satisfied in the case of a rotating black hole, the damping can be replaced by excitation. A particle production process (Hawking process) is considered that leads to the accumulation of particles on quasistationary levels near the black hole. Dynamical equilibrium can be established in the system between the processes of production and capture of particles by the black hole.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, 109–114, September, 1978. 相似文献