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1.
2.
The molecular structures of 1,3-benzodioxole and 1,3-indandione partially oriented in nematic solvents have been studied by NMR. Results for 1,3-indandione agree well with a planar model. The structural parameters are similar to those obtained by X-ray studies. No keto-enol tautomerism is observed. An anomalous structural result is obtained for 1,3-benzodioxole if the molecule is assumed to be planar. Dipolar couplings agree well with puckered model. The puckering angle is found to be about 15.5° ± 2°, similar to the values observed for TTF, TSeF and 2,5-dihydrofuran. 相似文献
3.
N. V. Stratan E. P. Koval’chuk J. Blazejowski 《Russian Journal of General Chemistry》2004,74(12):1900-1906
In terms of the ability for electrochemical transformations in acidic medium, the reactivity decreases in the order o-aminoacetophenone > p-aminoacetophenone > m-aminoacetophenone > aniline. The products of electrochemical polycondensation of the ortho and para isomers are conductors. Oxidative polycondensation of o-aminoacetophenone forms emeraldin hydrosulfate, and with p- and m-aminoacetophenones, emeraldin and leucoemeraldin are formed. In terms of thermal stability, polyacetoaminophenones can be ranked in the order poly-o-aminoacetophenone > poly-m-aminoacetophenone > poly-p-aminoacetophenone.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 2012–2018.Original Russian Text Copyright © 2004 by Stratan, Kovalchuk, Blazejowski.This revised version was published online in April 2005 with a corrected cover date. 相似文献
4.
5.
I.P. Koval Yu.N. Krynko P.V. Melnik N.G. Nakhodkin A.I. Shaldervan 《Surface science》1978,77(1):40-51
A technique is presented of electron mean free path determination in solids using the spectra of backscattered electrons. The mean free path without energy loss (λ0) in Ge, and the mean free paths for excitation of volume (λv) and surface (λs) plasmons in Al, are determined in the electron energy range E0 = 0.1–10 kev. The depth ds of surface plasmon localization is estimated for Al. 相似文献
6.
I. Štekl P. Čermák P. Beneš V. B. Brudanin K. N. Gusev V. G. Egorov A. A. Klimenko V. E. Kovalenko A. Kovalík N. I. Rukhadze A. V. Salamatin V. V. Timkin Ts. Vylov Ch. Briançon F. Šimkovic 《Czechoslovak Journal of Physics》2006,56(5):505-510
Present status of the experiment TGV II which is devoted to the measurement of double-beta decay of 106Cd is given. The low background spectrometer TGV II is installed in the Modane Underground Laboratory and has been running
from February 2005 with approx 10 grams of 106Cd enriched at 75%. After an analysis of 3736 hours of experimental data the new improved half-life limit for 2νEC/EC decay of 106Cd (0
g.s.
+
→ 0
g.s.
+
) is given as T
1
2/2ν
> 4.8 × 1019 years (90% CL). The search for 2νEC/EC decay of 106Cd to the excited states of 106Pd allows to determine the limits of the half-lives T
1
2/2ν
(0
g.s.
+
→ 2
1
+
) > 3.9 × 1019 years (90% CL) and T
1
2/2ν
(0
g.s.
+
→ 0
1
+
) > 5.8 × 1019 years (90% CL).
Presented by I. Štekl at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’05), Corfu, Greece, September
26–29, 2005. 相似文献
7.
M. A. Surmeneva R. A. Surmenev V. F. Pichugin N. N. Koval’ A. D. Teresov A. A. Ivanova I. Yu. Grubova V. P. Ignatov O. Primak M. Epple 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2013,7(5):944-951
Silicon-containing hydroxyapatite coatings 400–700 nm in thickness are prepared by means of radio-frequency (RF) magnetron sputtering on a heated (to 200°C) titanium substrate chemically etched and treated with a pulsed electron beam. The morphology and phase composition of the coating are studied. The morphology and roughness of the composite “calcium-phosphate coating-titanium substrate” differ depending on the treatment procedure of the substrate before deposition. The scratch test method is used to assess the adhesion strength of the coatings formed at different values of bias potential applied to the substrate. It is observed that the adhesion strength of the coating changes with decreasing crystallite size. 相似文献
8.
A. É. Bugrov S. Yu. Gus’kov V. B. Rozanov I. N. Burdonskii V. V. Gavrilov A. Yu. Gol’tsov E. V. Zhuzhukalo N. G. Koval’skii V. N. Kondrashov M. I. Pergament V. M. Petryakov S. D. Tsoi 《Journal of Experimental and Theoretical Physics》1999,88(3):441-448
We have experimentally investigated the interaction of high-power neodymium laser pulses in the intensity range 1013–1014 W/cm2 with flat low-density (0.5–10 mg/cm3) agar-agar targets under conditions of interest for problems of inertial nuclear fusion. Optical and x-ray methods with high
temporal and spatial resolution were used to examine the dependence of absorption and scattering of the incident beam on the
initial mean density and thickness of the irradiated samples. We show that when a porous target is irradiated, a bulk absorption
layer of high-temperature plasma is produced inside the target whose dimensions are determined by the initial density of the
material. The time dependence and spectral composition of the harmonics 2ω
0 and 3ω
0/2 observed in the plasma-scattered radiation are measured. A theoretical model is developed that describes the interaction
of high-power laser pulses with a porous medium. Predictions of the model, based on the hypothesis of two stages of homogenization
of the target material—a fast stage (0.1–0.3 ns) and a slow stage (1–3 ns), are in good agreement with the experimental data.
Zh. éksp. Teor. Fiz. 115, 805–818 (March 1999) 相似文献
9.
V. I. Gushenets N. N. Koval’ V. S. Tolkachev P. M. Shchanin 《Technical Physics》1999,44(11):1318-1321
The emission properties of a plasma cathode based on a nanosecond pulsed glow discharge with currents of up to 200A at a pressure
of 5×10−2 Pa are studied experimentally. Stable ignition and burning of the discharge are ensured if the current in the auxiliary pulsed
discharge is 25–30% of that in the main discharge and its pulse duration exceeds that of the main discharge by more than an
order of magnitude. Emission current pulses from the cathode with amplitudes of up to 140A fully reproduce the discharge current
and are determined by the transparency of the grid anode.
Zh. Tekh. Fiz. 69, 62–65 (November 1999) 相似文献
10.
Ivanov Yu. F. Koval N. N. Akhmadeev Yu. H. Uglov V. V. Shugurov V. V. Petrikova E. A. Krysina O. V. Prokopenko N. A. Azhazha I. I. 《Russian Physics Journal》2022,64(12):2207-2213
Russian Physics Journal - The method for deposition of high entropy alloy (HEA) films is discussed. It consists in the film deposition on a substrate in vacuum from multi-component gas-metal plasma... 相似文献