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排序方式: 共有268条查询结果,搜索用时 15 毫秒
71.
A. F. Krupnov M. Yu. Tretyakov G. Yu. Golubyatnikov A. M. Schitov S. A. Volokhov V. N. Markov 《International Journal of Infrared and Millimeter Waves》2000,21(3):343-354
The paper describes technique of quantitative analysis of a millimeter- and submillimeter-wave range multipliers performance in particular the measurement of the frequency conversion efficiency. The output power on each harmonic produced by the multiplier can be measured separately without any changes in the setup even in the case of simultaneous emission of all harmonics including the fundamental in a frequency range up to 1 THz and well above. The measuring technique primarily developed for high resolution microwave spectroscopy is based on absorption of radiation in spectral lines of rarefied sample gas and photo-acoustic method of the absorption detection. Sensitivity independence of the detection method on frequency and well known spectral parameters of the lines provide the technique with broadbandness, high spectral resolution and power measurement reliability. Principal limits of measurable radiation power may vary from nanowatts up to hundreds of watts. The technique permits real time operation convenient, e.g., for multiplier tuning. Practical examples include measurements of harmonic generation efficiency of multipliers of 78-118 GHz fundamental frequency range, and power measurement up to 6-th harmonic of 230 GHz fundamental radiation of phase locked Backward Wave Oscillator (BWO). 相似文献
72.
73.
A. I. Kolesnikov O. V. Malyshkina I. A. Kaplunov A. I. Ivanova S. A. Tretyakov R. M. Grechishkin E. Yu. Vorontsova 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(1):76-83
It is shown theoretically and experimentally that dislocations in paratellurite single crystals can be revealed using the piezo-optic effect. The mechanical-stress distribution near dislocations is calculated. Dislocations in the samples are observed using the photoelastic method and chemical etching. Data on the spatial distribution of dislocations in Czochralski-grown paratellurite crystals are reported. 相似文献
74.
N. A. Artiukhova K. Yu. Maryunina S. V. Fokin E. V. Tretyakov G. V. Romanenko A. V. Polushkin A. S. Bogomyakov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2013,62(10):2132-2140
A method was developed for the synthesis of a nitronyl nitroxide containing cyclopentane substituents in positions 4 and 5 of the imidazoline ring, viz., 2-(3-pyridyl)-4,5-bis(spiropentyl)-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (LCP). The reaction of CuII hexafluoroacetylacetonate with LCP affords different products depending on the reaction conditions: mononuclear [Cu(hfac)2(LCP)2], binuclear [Cu(hfac)2LCP]2, tetranuclear {[Cu(hfac)2]4(LCP)2}, or chain polymer {[Cu(hfac)2]3(LCP)2} n . Temperature changes induce structural transformations accompanied by a change in the spin state in exchange clusters in the solid [Cu(hfac)2LCP]2 and {[Cu(hfac)2]4(LCP)2}. 相似文献
75.
Back Cover: C(sp2)‐Coupled Nitronyl Nitroxide and Iminonitroxide Diradicals (Chem. Eur. J. 10/2014) 下载免费PDF全文
Dr. Svyatoslav Tolstikov Prof. Evgeny Tretyakov Dr. Sergey Fokin Dr. Elizaveta Suturina Prof. Galina Romanenko Dr. Artem Bogomyakov Dr. Dmitri Stass Dr. Alexander Maryasov Prof. Matvey Fedin Prof. Nina Gritsan Prof. Victor Ovcharenko 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(10):2968-2968
76.
Molecular-Thermodynamic Model of Solubilization in Direct Spherical Micelles of Nonionic Surfactants
Shchekin A. K. Volkov N. A. Koltsov I. N. Tretyakov N. Yu. Volkova S. S. Turnaeva E. A. 《Colloid Journal》2021,83(4):518-529
Colloid Journal - A thermodynamic model has been formulated for the formation work of a molecular aggregate consisting of molecules of a nonionic surfactant and a solubilisate in a... 相似文献
77.
78.
Tretyakov N. A. Bashorina N. V. Belozerova A. I. Maslivets A. N. 《Russian Journal of Organic Chemistry》2021,57(9):1423-1427
Russian Journal of Organic Chemistry - 8-Aroyl-3,4-dihydropyrrolo[2,1-c][1,4]oxazine-1,6,7(1H)-triones reacted with 1,3-diphenylguanidine to give... 相似文献
79.
Romanenko G. V. Fokin S. V. Chubakova E. T. Tretyakov E. V. Bogomyakov A. S. Ovcharenko V. I. 《Journal of Structural Chemistry》2021,62(12):1857-1862
Journal of Structural Chemistry - A 12-nuclear heterospin complex of Cu(II) hexafluoroacetylacetonate with dialkylpyrazolyl-substituted nitroxide [Cu2(hfac)4LBu/Et]6 is found, which has a... 相似文献
80.
V. I. Ovcharenko O. N. Chupakhin I. S. Kovalev E. V. Tretyakov G. V. Romanenko D. V. Stass 《Russian Chemical Bulletin》2008,57(10):2227-2229
The SNH reaction of lithiated 4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyl 3-oxide with quinoline N-oxide affords 4,4,5,5-tetramethyl-2-(1-oxidoquinolin-2-yl)-4,5-dihydro-1H-imidazole-1-oxyl 3-oxide. 相似文献