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1.
运用透射光栅光谱仪,对线聚焦高功率激光辐照到锗靶上产生的软X光激光进行光谱记录,利用衍射谱的对称性和已经绝对标定过的Kodak-101底片来完成对Kodak-SWR底片的绝对标定。 相似文献
2.
本文用“剖面不变性”确定等效电子热导系数,研究了TCA装置上阿尔芬波加热的能量平衡,结果与实验符合很好。证明本文所用的方法对不同装置、不同加热方式都适用。 相似文献
3.
The IR spectrum of 4-O-methyl-2,3,6-tri-O-nitromethyl-β-D-glucopyranoside has been interpreted in detail for the first time
based on complete calculation of the normal vibration frequencies and absolute intensities of its IR absorption bands and
a comparison of them with the corresponding experimental data. The results indicate that the location of the nitrates in cellulose
nitrates can be determined experimentally from separate components of complicated absorption bands in the ranges 1700–1600
and 900–800 cm−1 of the IR spectrum.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 1, pp. 43–51, January–February, 2008. 相似文献
4.
Consider a regular diffusion process X with finite speed measure m. Denote the normalized speed measure by μ. We prove that the uniform law of large numbers
holds if the class
has an envelope function that is μ-integrable, or if
is bounded in L
p(μ) for some p>1. In contrast with uniform laws of large numbers for i.i.d. random variables, we do not need conditions on the ‘size’ of
the class
in terms of bracketing or covering numbers. The result is a consequence of a number of asymptotic properties of diffusion
local time that we derive. We apply our abstract results to improve consistency results for the local time estimator (LTE)
and to prove consistency for a class of simple M-estimators.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
M. V. Korolevich R. G. Zhbankov L. V. Matusevich B. G. Derendyaev V. N. Piottukh-Peletskii 《Journal of Applied Spectroscopy》2001,68(6):930-941
The frequencies of the normal vibrations of the molecules of 2,6- and 3,6-di-O-nitro-methyl--D-glucopyranosides and 2,3,6-tri-O-nitro-methyl--D-glucopyranoside have been calculated within the valence-force-field approximation in combination with calculation of the absolute intensities of the IR absorption bands of these molecules by the CNDO/2 method. The regularities in the structure of the complex IR absorption bands characteristic for nitro groups formed as a result of selective nitrosubstitution have been explained. 相似文献
6.
7.
曲文孝 《核聚变与等离子体物理》2000,20(3):129-135
在TFTR及TEXF等装置上观测到的边界电子冷脉冲的输运现象是通常基于局部热导的瞬态输运理论所无法解释的。利用一个与电子温度剖面不变性相「容的且与在ρ=ρL(ρL≈0.7~0.8)处的局部电子热导相关的非局部电子热导模型来描述边界冷脉冲引起的电子温度变化的瞬态过程,发现此模型可定性地解释边界冷脉冲实验现象的几乎所有主要特征。 相似文献
8.
Enthalpies of solution have been measured from 5 to 85°C for aqueous tetraethyl- and tetrapropylammonium bromides, and the integral heat method is employed to evaluate
for these electrolytes over a wide temperature range. Data taken from the literature have been used to evaluate
for aqueous Bu4NBr over a similar temperature range. These data, along with similar data for Me4NBr, previously reported, have been used to evaluate absolute ionic heat capacities. While the absolute values agree only qualitatively with two other methods of division, the temperature dependences of the three methods essentially agree up to 65°C. Heat capacities due to structural effects on the solvent, obtained by subtracting the inherent heat capacities of the ions, are extraordinarily positive for all four tetraalkylammonium ions and have negative temperature coefficients, indicating that all four ions, including the tetramethylammonium ion, are structure-making ions. 相似文献
9.
CrystalStructureandMolecularAbsoluteConfigurationof(+)-Isocedranol(C_(15)H_(26)O)¥LiuJie;ChenMin-Qin(CenterofAnalysis&Measurem... 相似文献
10.
Reem A. Kamel Ahmed S. Abdel-Razek Abdelaaty Hamed Reham R. Ibrahim Hans Georg Stammler Marcel Frese 《Natural product research》2020,34(8):1080-1090
AbstractIsoshamixanthone (1), a new stereoisomeric pyrano xanthone together with the previously known fungal metabolites, epiisoshamixanthone (2), sterigmatocystin (3), arugosin C (4), norlichexanthone (5), diorcinol (6), ergosterol and methyllinoleate, were obtained from the endophytic fungal strain Aspergillus sp. ASCLA isolated from leaf tissues of the medicinal plant Callistemon subulatus. The chemical structure of the new xanthone (1) was elucidated by extensive 1D, 2D NMR, and ESI HR mass measurements, and by comparison with literature data. The constitutions and absolute configurations of 1 and epiisoshamixanthone (2) were additionally confirmed by X-ray crystallography. Compounds 1,2 were evaluated for their potential anticancer activity using the human cervix carcinoma cell line (KB-3-1). The antimicrobial activities of the fungal extract and compounds 1,2 were studied using a panel of pathogenic microorganisms as well. 相似文献