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排序方式: 共有118条查询结果,搜索用时 15 毫秒
1.
2.
I. A. Belogorokhov M. N. Martyshov E. V. Tikhonov M. O. Breusova V. E. Pushkarev P. A. Forsh A. V. Zoteev L. G. Tomilova D. R. Khokhlov 《JETP Letters》2007,85(12):655-657
The Raman spectra have been obtained and the temperature dependence of the conductivity of organic semiconductor structures based on butyl-substituted erbium monophthalocyanine and erbium triphthalocyanine has been studied. It has been found experimentally that the activation energy decreases dramatically and the Raman spectra exhibits four new peaks in the region of large Raman shifts as the molecular structure of the samples becomes more complicated. 相似文献
3.
V. E. Pushkarev A. V. Ivanov I. V. Zhukov E. V. Shulishov Yu. V. Tomilov 《Russian Chemical Bulletin》2004,53(3):554-560
New hexadecaalkyl-substituted diphthalocyanine complexes of lanthanides RPc2Ln (R = Et, or Bu; Ln = Lu, Dy, or Eu) were synthesized by three methods: in solution in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene, in a melt of a mixture of the reagents, and under microwave irradiation. The first of the above-mentioned procedures has an advantage for the preparation of Dy and Eu diphthalocyanines, whereas the melt synthesis is a method of choice for the preparation of Lu complexes. The reaction time decreases in going from the first to the third method. The structures of the complexes were confirmed by mass spectrometry, NMR spectroscopy, and electronic absorption spectroscopy. 相似文献
4.
New alkyl-substituted phosphorus phthalocyanines and triazatetrabenzocorroles were synthesized. The structures of these complexes
were confirmed by 1H, 13C, and 31P NMR spectroscopy, mass spectrometry, and electronic absorption spectroscopy.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1403–1407, July, 2007. 相似文献
5.
A. Yu. Tolbin V. E. Pushkarev L. G. Tomilova N. S. Zefirov 《Russian Chemical Bulletin》2006,55(7):1155-1158
New planar binuclear phthalocyanines sharing the benzene ring were synthesized and their spectral properties were studied.
Intense absorption in the near-IR region (∼850 nm) was observed for the first time.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1112–1115, July, 2006. 相似文献
6.
V. V. Aksenova R. M. Nikonova V. I. Lad’yanov N. B. Tamm E. V. Skokan B. E. Pushkarev 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(10):1749-1755
The oxidation of C60 and C70 fullerites and C60/C70 mixture is accompanied by the decomposition of the carbon frameworks of the molecules at annealing temperatures of 250 and 445°C. Fourier-IR and HPLC studies show that the oxidation/decomposition of C70 molecules is more active than that of C60. The stages of fullerite interaction with oxygen while heating in air were determined. 相似文献
7.
X-ray diffraction investigations have revealed that, in the system of solid solutions 0.9(Na1 ? x K x Bi)1/2TiO3-0.1Bi(ZnTi)1/2O3, there is a morphotropic phase boundary in the potassium concentration range of x ≈ 0.25, which separates the regions of compositions with rhombohedral (R3c) and tetragonal (P4mm) structures. It has been shown that, in the vicinity of this boundary, ceramic samples of the studied system exhibit properties of relaxor ferroelectrics. The results of the investigation into the dielectric properties of relaxor ceramics of the composition x = 0.3 with the use of the impedance spectra measured in the frequency range from 25 to 106 Hz at temperatures from 100 to 900 K have been presented. It has been found that, in the temperature region of the existence of the relaxor state lying below the temperature corresponding to the maximum of the real part of the permittivity (T′ m = 550 K), the dielectric polarization is determined by the sum of the contributions from the matrix and dipole clusters. The temperature dependence of the contribution from the clusters, which is determined by the kinetics of their formation and freezing, is characterized by a curve with the maximum at approximately 400 K. The process of freezing of dipole clusters occurs over an extended temperature range of more than 200 K. 相似文献
8.
Onorato M Osborne AR Serio M Resio D Pushkarev A Zakharov VE Brandini C 《Physical review letters》2002,89(14):144501
We study the long-time evolution of deep-water ocean surface waves in order to better understand the behavior of the nonlinear interaction processes that need to be accurately predicted in numerical models of wind-generated ocean surface waves. Of particular interest are those nonlinear interactions which are predicted by weak turbulence theory to result in a wave energy spectrum of the form of [k](-2.5). We numerically implement the primitive Euler equations for surface waves and demonstrate agreement between weak turbulence theory and the numerical results. 相似文献
9.
10.
The dielectric properties of the ceramics of (1 − x)BiFeO3 − x(KBi)1/2TiO3 (0.40 < x < 0.85) solid solutions with an orthorhombic structure have been studied using impedance spectroscopy in the frequency range
25–106 Hz at different temperatures. It has been shown that these solid solutions undergo a diffuse ferroelectric phase transition.
The Curie temperature is found to be in the range 620–640 K. The activation energies of dielectric polarization relaxation
(δE
M
) and dc charge carriers (ΔE
dc) are determined. It has been established that, in the vicinity of 460 K, ΔE
dc increases jumpwise as the temperature increases. 相似文献