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101.
The New Data for the Reaction of Arylenedioxy Trihalogenophosphoranes with Alkyl- and Arylacetylenes
Vladimir F. Mironov Alfiya A. Shtyrlina Ravil R. Petrov Tamara A. Baronova Fedor F. Alekseev Elena N. Varaksina 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1381-1385
The new data concerning the reaction between substituted arylenedioxy trihalogenophosphoranes and monoalkyl- or arylacetylenes are summarized. The reaction leads to formation of six-membered heterocycles-2-oxo-4-R-benzo[ e ]-1,2-oxaphosphorin-3-enes. The substituent effects in the phosphorane and acetylene molecules on the ipso -substitution and halogenation regiochemistry are discussed. The ipso -substitution of tert -butyl group on chlorine and the exchange of bromine on chlorine and iodine on hydrogen have been observed, along with formation of benzophosphorines. The interaction of tetrachloro- ortho -benzoquinone with phosphorus trichloride and arylacetylenes is proposed as a new modification of the reaction leading to the formation of benzo[ e ]-1,2-oxaphosphorines. The structures of some benzo[ e ]-1,2-oxaphosphorines are determined by the single crystal X-ray diffraction. 相似文献
102.
K. Olimov V. V. Glagolev K. G. Gulamov S. L. Lutpullaev A. R. Kurbanov A. K. Olimov V. I. Petrov A. A. Yuldashev 《Physics of Atomic Nuclei》2013,76(7):881-882
New experimental data on the cross sections for the yield of excited 6Li* and 7Li* nuclei and on their contributions to the production of 4He + 2H and 4He+3H light dinuclear systems in 16O p collisions at a momentumof 3.25 A GeV/c per nucleon are presented. 相似文献
103.
Conductivity as a Sensor for Monitoring Relative Magnesium Corrosion Rates in Real‐time,in Serum‐containing Media under Cell Culture Conditions
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Kolade Ojo Tracy Hopkins Madhura Joshi Pravahan Salunke Guangqi Zhang Keaton Nahan Zhannping Zhang Daoli Zhao Sarah K. Pixley Vesselin Shanov William R. Heineman 《Electroanalysis》2016,28(12):3000-3008
Because controlling the corrosion rate of magnesium metal will be crucial to the success of biomedical implants containing pure magnesium or magnesium alloys, many ways have been sought to improve in vitro tests to analyze corrosion rates, and also to identify new methods of preparing or post‐processing magnesium. In this work, for an in vitro assay, we explored the use of a commercially available conductivity sensor to study magnesium corrosion under cell culture conditions that duplicate many physiologically appropriate parameters. With this sensor, we studied the corrosion of two previously untested magnesium single crystal samples that differed in surface treatments that could alter corrosion rates. The results show that the relative conductivity changes in (mS/cm) over the total time of immersion were proportional to the corrosion rates in (mm/y) and also to the total magnesium released, as detected by inductively coupled plasma mass spectrometry (ICP‐MS). 相似文献
104.
105.
Yu. D. Zavartsev M. V. Zavertyaev A. I. Zagumenniy A. F. Zerrouk V. A. Kozlov S. A. Kutovoi N. V. Pestovskii A. A. Petrov S. Yu. Savinov 《Bulletin of the Lebedev Physics Institute》2016,43(11):336-339
Optical and luminescence characteristics of Lu2+2ySi1-yO5+y (LFS) scintillation crystals are studied before and after irradiation with doses to 45 Mrad from a 60Co source. LFS crystals were doped with Ce3+, Sc3+, Ca2+, and Y3+ ions with various concentrations. The dependence of the radiation resistance of LFS crystals on Ce ion concentration is detected. For the crystal of composition Ce:Sc:Ca:Y:LFS, it was found that its optical transmission (OT) and pulsed cathodoluminescence (PCL) spectra before irradiation do not differ from the spectra measured after irradiation with a dose of 45 Mrad within experimental error. The nature of the radiation resistance of rare-earth lutetium oxyorthosilicates (LFS) is discussed. 相似文献
106.
107.
N. Kh. Petrov D. A. Ivanov I. V. Kryukov A. D. Svirida Yu. A. Shandarov M. V. Alfimov 《Journal of fluorescence》2018,28(4):883-887
The time-resolved Stokes shift of fluorescence of styryl dye, trans-4-[4-(dimethylamino)-styryl]-1-methylpyridinium iodide (DASPI), and its host-guest complexes with cucurbit[6]uril (CB[6]) was studied by up-conversion technique on a 5 ps time scale. In all cases, the solvation time correlation function – that describes relaxation of the fluorescent state - contains two components. The time constant of the first component, which is related to the vibrational relaxation of the dye cation, increases from 118 fs without CB[6] to 224 fs in the presence CB[6]. It suggests the production of CB[6] complexes to disturb the hydrogen-bond net in the vicinity of DASPI cation. The time constant of the second component, which is associated with solvation, changes from 0.81 ps without CB[6] to 1.15 ps in the presence of the cavitand. The observed increase can be related to the displacement of the dye cation deeper into CB[6] that allows considering DASPI-CB[6] complexes as a light-controlled molecular machine with a response time on the picosecond scale. 相似文献
108.
Alexander M. Toikka Alexandra Yu. Pulyalina Andrey V. Petrov 《Mendeleev Communications》2021,31(1):79-80
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109.
B. A. Demidov V. P. Efremov Yu. G. Kalinin V. A. Petrov S. I. Tkachenko K. V. Chukbar 《Technical Physics》2012,57(3):405-409
The time ranges of the fracture of polymethylmethacrylate and polystyrene during the action of a shock wave generated by a
high-current pulsed electron beam are experimentally determined using laser probing in combination with electron-optical chronography.
It is shown that fractures occur during unloading of a material, i.e., after the passage of the shock wave. Although the characters
of fracture of these polymers near the surface irradiated by electron beam are different, the fracture wave velocities in
them are found to be close. 相似文献
110.
S. N. Buravova E. V. Petrov G. R. Saikova M. I. Alymov 《Doklady Physical Chemistry》2018,481(2):114-116
The formation of localized deformation bands is accompanied by the mass transfer of particles of the matrix material (interstitial atoms, impurities, etc.) toward faults in the material being destroyed and by the emergence of stress oscillations in a mode of ultrasonic vibrations lasting several orders of magnitude longer than the initial pulse. It was assumed that dislocations generated under pulsed deformation are the cause of the migration of particles. 相似文献