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41.
采用傅里叶变换红外光谱(FTIR)及其二阶导数谱对不同生长年限当归药材进行分析研究.结果表明,不同生长年限当归药材的红外图谱较为相似,仅从一维谱图上无法反映出不同生长年限当归药材的红外特征谱明显的异同,但通过二阶导数图谱中1771、1747、1712、1559、1514、1466、766、711cm-1和668cm-1处的峰型差异可发现不同生长年限当归药材之间的一些成分存在较明显的差异.由于生长时间不同,导致它们的化学成分存在差异,所以体现了各自的红外特征谱,其中第三年当归药材与第一年和第二年当归药材间差异较大. 相似文献
42.
43.
1 INTRODUCTIONWith the invention of lasers[1] and the observation of second-harmonic generation in quartz[2], nonlinear optics(NLO), as a cornerstone of photonics, has been booming since 1960's. And intense interest has been aroused to search materials exhibiting appropriate nonlinear optical properties suitable for the construction of practical optical devices for the important techniques such as frequency converting, signal processing and optical computing[3~6]. In order to determine … 相似文献
44.
SABen-Hao CAIXu TAIAn ZHOUDai-Mei 《理论物理通讯》2004,42(3):403-406
We present the simulation results of the net charge fluctuation in Au Au collisions at √Snn=130 GeV from a dynamic model, JPCIAE, and its revisions. The simulations are done for the quark-gluon matter, the directly produced pions, the pion matter, and the hadron matter. The simulated net charge fluctuation of the quark-gluon matter is close to the thermal model prediction for the quark-gluon gas. However, the discrepancy exists comparing the simulated net charge fluctuation for directly produced pions and the pion matter with the thermal model prediction for pion gas and the resonance pion gas, respectively. The net charge fluctuation of hadron matter from default JPCIAE simulations is nearly 3.5 times larger than quark-gluon matter. A discussion is given for the net charge fluctuation as an evidence of QGP phase transition. 相似文献
45.
We construct, for various classes of p-adic-valued functions, stochastic integrals with respect to the Poisson random measure. This leads to the construction of Markov processes over the field of p-adic numbers by means of stochastic differential equations. 相似文献
46.
A. N. Kochubei 《Ukrainian Mathematical Journal》2008,60(4):551-562
Within the Bochner-Phillips functional calculus and Hirsch functional calculus, we describe the operators of distributed-order
differentiation and integration as functions of the classical operators of differentiation and integration, respectively.
Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 60, No. 4, pp. 478–486, April, 2008. 相似文献
47.
S. A. Bel’kov P. D. Gasparyan Yu. K. Kochubei E. I. Mitrofanov 《Journal of Experimental and Theoretical Physics》1997,84(2):272-280
The ionization kinetics of a transient nonequilibrium highly charged ion plasma are investigated in the average-ion approximation.
Approximations of a hydrogenic ion, whose energy levels depend either on the principal quantum number alone or on the principal
and orbital angular momentum quantum numbers, are considered as atom models. The results of calculations of various plasma
characteristics performed within this model are presented, and a comparison with previously published data, as well as with
calculations in the chemical-bond approximation, is performed. It is shown that the average-ion model satisfactorily describes
the spectral characteristics of a nonideal plasma.
Zh. éksp. Teor. Fiz. 111, 496–513 (February 1997) 相似文献
48.
I. B. Barkan V. N. Ishchenko S. A. Kochubei D. I. Lunenok A. M. Razhev 《Applied Physics A: Materials Science & Processing》1987,44(2):167-170
A new phenomenon of a strong irreversible variation of the refractive index (n–0.2) in a skin layer (thickness 300 Å) has been discovered. The effect arises under the strong absorption of high-power uv radiation (249 nm, 5 ns, 20 MW/cm2). The characteristics of the subsurface photorefractive effect (SPRE) were identified by using the data on measurements of the reflection coefficient of a crystal and of the diffraction efficiency of a recorded phase grating. 相似文献
49.
P. MORLIÉRE M. BAZIN L. DUBERTRET R. SANTUS T. SA E. MELO G. HÜPPE J. HAIGLE P. FORLOT A. BERNARD 《Photochemistry and photobiology》1991,53(1):13-19
5-Geranoxypsoralen, commonly called bergamottin, a major furocoumarin contained in bergamot oil, is reported in vitro as a highly photoreactive psoralen. In ethanol, it exhibits quite a high triplet state quantum yield (approximately 0.37). The triplet state is involved in subsequent photochemistry which depends on the initial concentration and on the presence of oxygen. In contrast to most psoralens, absorption and fluorescence data suggest that 5-geranoxypsoralen does not interact with DNA in the dark. No UVA-induced interstrand cross-links in DNA were shown. 相似文献
50.