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1.
Electron and IR spectroscopy, as well as the data on the isotopic analog 15NO2, were used for the studies of the reaction of nitrogen dioxide (NO2) with thin layers of the six-coordinated FeIII-porphyrin nitro complex with trans-1-methylimidazole ligand Fe(TPP)(1-MeIm)(NO2) (TPP is the meso-tetraphenylporphyrinate dianion), which is a heme-modelling system. It was shown that, like in the case of the five-coordinated nitrite complex, additional portions of NO2 promote the nitrite-to-nitrate transformation, accompanied by the evolution of NO. The reaction leads to the formation in the layer of five- and six-coordinated Fe-porphyrin nitrate complexes and a small amount of imidazole complexes FeIII(TPP)(1-MeIm)2 with the outersphere nitrate anion. The latter complex became predominate after treatment of this layer with additional portion of 1-methylimidazole. 相似文献
2.
D. L. Hovhannisyan A. H. Vardanyan G. D. Hovhannisyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2016,51(4):323-334
The results of theoretical research and numerical simulation of the nonlinear interaction process of mutually orthogonal and linearly polarized IR subpicosecond laser pulses with the one-dimensional periodic structure of the GaAs/ZnTe are presented. In particular, the interaction of such pulses with the equal amplitude electric field of 70.71 MV/m, with the duration of 333 fs at the central wavelength λ0 = 10 μm, with the periodic structure of the GaAs and the ZnTe with the thickness of layers equal to λ0/2nGaAs = 1.527 μm and λ0/4nZnTe = 0.931 μm, respectively, and with the number of periods equal to 100 is considered. It is shown that the efficiency of generation of sum and difference frequencies is proportional to the phase difference of the interacting IR pump pulses. 相似文献
3.
M. L. Petrosyan L. A. Gabrielyan Y. R. Nazaryan G. Kh. Tovmasyan K. B. Hovhannisyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2007,42(1):38-41
Undulator for terahertz FEL is created of ferrite materials. The length of the undulator period is 9 cm and the number of periods is 27. By means of selection and redistribution of magnetic elements it was succeeded to reduce the spread in amplitudes of the magnetic field down to 7%. Additional windings in magnetic elements were used to compensate for the residual spread. The needed focusing gradient of the magnetic field is obtained by means of relative displacement, along the x-axis, of alternating poles with opposite signs of the magnetic field. The undulator parameters, including the properties of focusing in the horizontal plane, are studied. 相似文献
4.
V. K. Abrahamyan N. H. Hakobyan V. M. Aroutiounian V. G. Babajanyan H. L. Margaryan D. L. Hovhannisyan A. T. Poghosyan D. K. Pokhsraryan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2009,44(2):84-90
We present results of studies of main characteristics of electrically-controlled retarders fabricated on the basis of planar- and twist-oriented liquid crystals (LC). The investigated characteristics are time of switching and the calibration curve of controllable phase incursion. Computer simulation and numerical calculations of the processes of LC director reorientation in an external electric field have been performed. Based on LabView software a special program is constructed for computer control of the shape, frequency, and amplitude of the external voltage applied to LC cell. An experiment has been implemented on realization, with use of this program, of the prescribed phase retardation of an optical beam. Calculated results agree with experimental data. 相似文献
5.
L. A. Haroutunyan K. G. Trouni G. M. Hovhannisyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2011,46(5):239-241
A new scheme of X-ray phase contrast imaging, based on the previously suggested three-block interferometer composed by multilevel
Fresnel zone plates, is considered. Two significant features, namely, image optical magnification and low requirements on
the spatial and temporal coherency of incident radiation are combined in this scheme. 相似文献
6.
L. A. Gabrielyan M. K. Hovhannisyan M. L. Petrosyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2014,49(4):139-143
Experimental study of magnetic characteristics of planar magnet undulator for terahertz FEL has been carried out with use of pulsed-wire method. Special attention was given to the procedure of measurement of the second integral of undulator magnetic field, which shows variation of the beam position at passing the undulator magnetic system. 相似文献
7.
The action of arylsulfonyl chlorides on 2-amino-4-methoxy-6-methylpyrimidine in pyridine gave 2-arylsulfonylamido-4-methoxy-6-methylpyrimidines, which were alkylated at the amide fragment, while the action of hydrazine hydrate led to nucleophilic replacement of the methoxy group. The resultant hydrazinopyrimidines were converted into azidopyrimidines and N-pyrimidinyldithiocarbazinates. Potassium salt of 2-p-toluenesulfonylamido-4-methoxy-6-methylpyrimidine dithiocarbazinate reacted with dimethyl sulfate to give the S-methyl derivative, while the reaction with chloroacetonitrile gave thiazolidinylaminopyrimidine. The chlorination using N-chlorosuccinimide yielded only 5-chloropyrimidines. 相似文献
8.
G. A. Egiazaryan Zh. B. Khachatryan E. S. Badalyan E. I. Ter-Gevorgyan V. N. Hovhannisyan 《Technical Physics》2006,51(2):209-215
The mechanisms governing the distribution of the longitudinal electron flows over the cathode surface in a discharge with oscillating electrons are studied experimentally. The influence of the discharge gap length on the magnitude and distribution of the electron flows is investigated. It is shown that intense longitudinal electron flows in a tube of diameter d a =31 mm can form only with short anodes of length l a =2.5–3.5 cm. The distributions of the electron current over the cathode surface at various discharge conditions are determined. 相似文献
9.
A. R. Balabekyan A. S. Danagulyan J. R. Drnoyan G. H. Hovhannisyan J. Adam V. G. Kalinnikov M. I. Krivopustov V. S. Pronskikh V. I. Stegailov A. A. Solnyshkin P. Chaloun V. M. Tsoupko-Sitnikov S. G. Mashnik K. K. Gudima 《Physics of Atomic Nuclei》2006,69(9):1485-1495
We measure cross sections for residual nuclide formation in the mass range 7 ≤ A ≤ 96 caused by bombardment with protons and deuterons of 3.65-GeV/nucleon energy of enriched tin isotopes (112,118,120,124Sn). The experimental data are compared with calculations by the codes FLUKA, LAHET, CEM03, and LAQGSM03. Scaling behavior
is observed for the whole mass region of residual nuclei, showing a possible multifragmentation mechanism for the formation
of light products (7 ≤ A ≤ 30). Our analysis of the isoscaling dependence also shows a possible contribution of multifragmentation to the production
of heavier nuclides, in the mass region 40 ≤ A ≤ 80.
The text was submitted by the authors in English. 相似文献
10.
The coefficients of symmetry energy term for fragments with Z = 4, 11, 12 measured in multifragmentation reactions initiated by proton and deuteron with energy of 3.65 A GeV on enriched tin isotopes 112,118,120,124Sn are determined. The dependence of isoscaling parameter on the excitation energy, the temperature of fragmenting systems
and the density ratio for heavy mass products are analyzed. 相似文献