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101.
I. M. Davletbaeva V. F. Shkodich A. M. Gumerov O. Yu. Emelina A. V. Naumov 《Polymer Science Series A》2010,52(4):392-397
The interaction of 2,4-toluylene diisocyanate with open-chain analogs of crown ethers containing potassium alcoholate groups
is studied, and the mechanism of stabilization of the formed O-polyisocyanate end units via intermolecular interactions is proposed. The electron delocalization in intermolecular cyclic
structures may be responsible for electron-transfer processes in the polymers under study. 相似文献
102.
A. N. Naumov F. Giammanco D. A. Sidorov-Biryukov A. B. Fedotov P. Marsili A. Ruffini A. M. Zheltikov 《JETP Letters》2001,73(6):263-267
Coherent four-wave mixing (FWM) of laser pulses in gas-filled hollow fibers is studied. The experimental data and the expressions derived for the amplitude of the FWM signal indicate that the excitation of higher order waveguide modes is an important physical factor having a considerable influence on nonlinear optical processes in hollow fibers. 相似文献
103.
104.
N. D. Naumov 《Doklady Physics》2002,47(12):839-841
105.
V. A. Nikitenko A. I. Tereshchenko V. P. Kucheruk N. P. Naumov P. G. Pas'ko 《Journal of Applied Spectroscopy》1989,50(5):475-478
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 50, No. 5, pp. 750–753, May, 1989. 相似文献
106.
107.
L. A. Nurtdinova V. V. Semashko A. K. Naumov R. Yu. Abdulsabirov S. L. Korableva 《Physics of the Solid State》2005,47(8):1463-1466
The results of spectral kinetic studies of several fluoride crystals activated by Yb3+ and Tm3+ ions are presented, and their possible application as cooling elements of optical refrigerators is discussed. Optimum excitation conditions for the laser cooling effect in these crystals are found. The cooling efficiency is established to depend on the degree of order in the active medium. 相似文献
108.
N. Naumov V. Petrovskiy E. Protsenko V. Yermachenko 《Applied physics. B, Lasers and optics》1997,65(4-5):589-593
4 gas laser with an intracavity absorbing cell is studied experimentally and theoretically at a modulation frequency approximately
equal to the intermode beat frequency. It is revealed that in the vicinity of the absorption-line centre the intensity of
every mode for certain system parameters displays resonance structures narrower than the homogeneous line width of the absorption
line. This occurs when the range of mode synchronization is near the absorption-line centre and its size is less than the
homogeneous width of the absorption line.
Received: 29 February 1996/Revised version: 4 February 1997 相似文献
109.
Single‐Crystal‐to‐Single‐Crystal Transition in an Enantiopure [7]Helquat Salt: The First Observation of a Reversible Phase Transition in a Helicene‐Like Compound 下载免费PDF全文
Dr. Naba K. Nath Lukáš Severa Dr. Roman A. Kunetskiy Prof. Ivana Císařová Prof. Michal Fulem Prof. Květoslav Růžička Dr. Dušan Koval Dr. Václav Kašička Dr. Filip Teplý Prof. Panče Naumov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(39):13508-13512
Here it is reported that crystals of an enantiopure [7]helquat salt undergo reversible thermal solid–solid phase transition at 404 K. Differential scanning calorimetry (DSC), capillary electrophoresis (CE), and X‐ray diffraction analysis were used to unravel the mechanistic details of this process. The single‐crystal‐to‐single‐crystal course enabled direct monitoring of the structural changes by in situ variable‐temperature X‐ray diffraction, thus providing the first direct evidence of a solid phase transition in a helicene‐like compound. 相似文献
110.
T. I. Devyatkina S. I. Luchneva A. E. Borisova E. S. Belyaev M. G. Mikhailenko V. V. Rogozhin V. I. Naumov 《Russian Journal of Applied Chemistry》2017,90(7):1075-1081
Technique for deposition of a nickel coating onto various aluminum alloys was developed. This coating can be used both independently and as a sublayer under multilayer coatings and, in particular, under those of nickel, tin–bismuth, lustrous nickel, and lustrous chromium. The technique includes anodization, chemical treatment, and electrodeposition of nickel in a special solution. The working modes of the anodization electrolyte were chosen and the necessity for a preliminary chemical treatment of the oxide film being formed was substantiated. A composition of the acid electrolyte for the subsequent nickel plating was developed with buffer and improving additives. The thus deposited electroplated nickel coatings exhibit a high adhesion to the aluminum base without additional thermal treatment. This makes it possible not only to reduce the technological time for deposition of the subsequent multilayer coatings, but also to fully automate the whole process. 相似文献