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2.
The cocrystal of 1,2-bis(diphenylphosphinoyl)ethane (DPPEO) with phenol (1:1) were studied theoretically with AM1, PM3, MNDO and MINDO/3 semi-empirical methods to elucidate its structure. The bond lengths and angles from theoretical studies of molecule DPPEO/phenol (1:1) were found to be as expected. Theoretical results, concerning with intermolecular van der Waals forces in cocrystal, were compared with the previously obtained experimental data and AM1 results were found to be the best fit for bond lengths and angles of DPPEO/phenol. 相似文献
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6.
B. V. Derjaguin 《Progress in Surface Science》1992,40(1-4):240-251
A review is presented about research on surface forces and surface interactions conducted over the past half-century, with some emphasis on the pioneering contributions of the Department of Surface Phenomena at the Institute of Physical Chemistry of the USSR Academy of Sciences. 相似文献
7.
In this short communication, we have evaluated the effect of thermal velocity of the plasma particles on the energy of resonantly
interacting energetic electrons with the propagating whistler mode waves as a function of wave frequency and L-value for the
normal and disturbed magnetospheric conditions. During the disturbed conditions when the magnetosphere is depleted in electron
density, the resonance energy of the electron enhances by an order of magnitude at higher latitudes, whereas the effect is
small at low latitudes. An attempt is made to explain the enhanced wave activity observed during magnetic storm periods. 相似文献
8.
Dispersion Compensation in Externally Modulated Transmission System Using Chirped Fiber Grating 总被引:1,自引:0,他引:1
We present an externally modulated NTSC AM-VSB erbium-doped fiber amplifier (EDFA)-repeated system in the 1550 nm region which uses a chirped fiber grating (CFG) as a dispersion compensation device. In contrast to the conventional externally modulated fiber optical CATV systems, either with or without dispersion compensation fiber (DCF), good performances of carrier-to-noise ratio (CNR) ≥50 dB, composite second order (CSO) ≥74 dB, and composite triple beat (CTB) ≥65 dB were achieved for the full channel band after a 100-km single-mode fiber (SMF) transmission. 相似文献
9.
This article presents the comparison of approximate and exact small-signal theories for analyzing the influence of the higher-order dispersion terms on dispersive optical communication systems operating near zero dispersion wavelength for linear single-mode fiber. For the approximate theory, the generalized conversion matrix has been reported and gives the transfer function of intensity and phase from the fiber input to fiber output for a laser source including the influence of any higher-order dispersion term. In addition, expressions for the small-signal frequency response and the relative intensity noise (RIN) response of an ultrafast laser diode including noises are derived. However, it is observed that the approximation assumed for the second-order dispersion term for the approximate analysis is not valid. From the approximate theory, the exact generalized conversion matrix and exact expressions for small-signal frequency response and relative intensity noise (RIN) are obtained. We show that for the exact theory, the second-order dispersion term has no effect on intensity and frequency response even at large modulating frequencies and large propagation distances contrary to the approximate theory as reported by other authors. But we show that third-order dispersion term certainly has some minute impact on the frequency and RIN response for long distance links at high modulating frequencies. 相似文献
10.
A. A. Afanas'ev V. M. Katarkevich A. N. Rubinov T. Sh. Éfendiev 《Journal of Applied Spectroscopy》2002,69(5):782-787
Spatial redistribution of microparticles in a suspension on exposure to the interference laser field depending on the parameters of the particles and the field characteristics has been analyzed theoretically. Results of experimental investigations are presented that illustrate the capture of an ensemble of polymeric small spheres and also of the lymphocytes of human blood and other microparticles in a liquid in the interference radiation bands of the He–Ne laser. 相似文献