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121.
Conclusions Oxidation of cyclohexenyl hydroperoxide by molecular oxygen in the presence of penta(dimethylsulfoxido)vanadyl hexathiocyanatoplatinate proceeds at a high rate at low temperatures with the formation of bifunctional, oxygen-containing products. The main route of the reaction is the molecular oxidation of the hydroperoxide with ring opening in a complex [Catm...HOORn]; oxidation of cyclohexenyl hydroperoxide to a dihydroperoxide takes place simultaneously by a chain mechanism.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 48–53, January, 1987. 相似文献
122.
G. A. Desyatkov A. Zh. Zhainakov P. V. Kozlov V. M. Lelevkin M. A. Samsonov V. S. Slobodyanyuk V. S. Éngel'sht 《Fluid Dynamics》1978,13(5):718-724
The mechanism of conducting-gas acceleration in an electric arc by intrinsic magnetic field was first investigated in [1]. Further theoretical study of this question was associated with the numerical calculation of arcs [2–7]. A more general approach to the solution of the problem was realized in [4], where the finite-difference method was used. Integral calculational models were developed in [5–7]. The present work proposes a modified version of the difference method [4] and a series of integral methods for the calculation of the conducting-gas flow in a high-current electric arc. The development of integral methods is of interest in that they are usually associated with adequate accuracy in determining integral values and values averaged over the cross section by a relatively simple calculation, and also allow the solution of the problem to be obtained in a number of situations when the realization of a difference method is complicated. The results of different calculation methods are compared. The effect of conditions in the initial cross section of the calculation region of the arc on its characteristics is investigated and a numerical analysis of the heating and acceleration of conducting gas is carried out.Translated from Izvestiya Akademiya Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 103–110, September–October, 1978. 相似文献
123.
Delahaye É Eyele-Mezui S Diop M Leuvrey C Rabu P Rogez G 《Dalton transactions (Cambridge, England : 2003)》2010,39(44):10577-10580
Synthesis of new heterometallic layered magnets with controlled chirality have been achieved by insertion of chiral and non-chiral salen-type Ni(II) complexes into copper and cobalt layered simple hydroxides. 相似文献
124.
An analysis is made of the possibility of focusing 10–30 keV charge-compensated proton beams with a current of 1 kA and an
area compression coefficient >1.5×103. To obtain a high degree of compression a combination of ballistic focusing and magnetic compression is used. The parameters
of the focusing channel are determined and an estimate is made of the possible effect of the compensating electron background
on the effectiveness of focusing of the proton beam.
Zh. Tekh. Fiz. 67, 73–80 (May 1997) 相似文献
125.
B. A. Arbuzov O. Éxsner A. P. Timosheva V. E. Kataev S. G. Vul'fson A. N. Vereshchagin 《Russian Chemical Bulletin》1976,25(6):1206-1212
1. | The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical. |
2. | In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane. |
3. | The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers. |
126.
M. E. Élyashberg Yu. Z. Karasev É. R. Martirosyan 《Journal of Structural Chemistry》1995,36(3):502-509
Major axioms underlying structure elucidation of molecules by their characteristic spectral data are considered. The amount
of information obtained by solving the problem on structure elucidation of molecules serves as a basis to evaluate the quality
of solution. Conditions for computer-aided solution of problems using expert systems (ES) are analyzed. Reasons for incorrect
or zero solutions and for inconsistencies leading to negative results are examined. The role of additional information as
a necessary condition for correct solution is discussed. On the basis of this analysis, a general strategy for structure elucidation
of molecules by their spectra using ES is suggested. The principal idea is to use the iteration method, gradually increasing
the rigidity of constraints. Strategies named ARCHEOLOGIST and SCULPTOR are discussed. Examples are given.
Russian Scientific Research Institute of Organic Synthesis. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 3, pp. 548–558, May–June, 1995.
Translated by L. Smolina 相似文献
127.
Effects of Ultraviolet Radiation (UVA+UVB) and Copper on the Morphology,Ultrastructural Organization and Physiological Responses of the Red Alga Pterocladiella capillacea 下载免费PDF全文
Éder C. Schmidt Marianne Kreusch Marthiellen R. de L. Felix Debora T. Pereira Giulia B. Costa Carmen Simioni Luciane C. Ouriques Francine L. Farias‐Soares Neusa Steiner Fungyi Chow Fernanda Ramlov Marcelo Maraschin Zenilda L. Bouzon 《Photochemistry and photobiology》2015,91(2):359-370
The effect of ultraviolet (UV) radiation and copper (Cu) on apical segments of Pterocladiella capillacea was examined under two different conditions of radiation, PAR (control) and PAR+UVA+UVB (PAR+UVAB), and three copper concentrations, ranging from 0 (control) to 0.62, 1.25 and 2.50 μm . Algae were exposed in vitro to photosynthetically active radiation (PAR) at 70 μmol photons m?2 s?1, PAR + UVB at 0.35 W m?2 and PAR +UVA at 0.70 W m?2 during a 12‐h photocycle for 3 h each day for 7 days. The effects of radiation and copper on growth rates, content of photosynthetic pigments and photosynthetic performance were analyzed. In addition, samples were processed for light and transmission electron microscopy. The content of photosynthetic pigments decreased after exposure to radiation and Cu. Compared with PAR radiation and copper treatments modified the kinetics patterns of the photosynthesis/irradiance curve. The treatments also caused changes in the ultrastructure of cortical and subcortical cells, including increased cell wall thickness and accumulation of plastoglobuli, as well as changes in the organization of chloroplasts. The results indicate that the synergistic interaction between UV radiation and Cu in P. capillacea, led to the failure of protective mechanisms and causing more drastic changes and cellular imbalances. 相似文献
128.
Composites consisting of polyethylene and porous fillers with various pore sizes (from 22 to 115 Å) and surface types have been investigated. It is shown that the polymer filling the pores takes part in the deformation processes. The modulus of elasticity of the filled polymers is directly proportional to the filler surface per gram polymer. It is proposed to characterize the activity of the fillers by reference to the slope of the straight lines E-S with the hydrodynamic effect excluded.Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 2, pp. 253–258, March–April, 1973. 相似文献
129.
130.
ADOLFO V. T. CARTAXO JOÃO L. REBOLA NATAŠA B. PAVLOVIĆ PEDRO M. A. CHARRUA DANIEL D. T. FONSECA JOSÉ A. P. MORGADO 《Fiber and Integrated Optics》2013,32(3-4):331-352
Abstract This article introduces the main achievements resulting from the DWDM/ODC project. The five areas of research activity within the DWDM/ODC project cover some of the main issues of design and development of dense wavelength division multiplexing systems for transparent optical networks. These issues are: performance assessment with arbitrary optical filtering; performance of signaling formats; dispersion compensation strategies for directly and externally modulated systems in presence of nonlinear transmission-induced degradation; and the impact of noise and crosstalk in the extent of transparent optical networks. All five areas of research activity have contributed significantly to a better understanding of the limitations present in dense wavelength division multiplexing systems. 相似文献