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21.
L.A. Gribov 《Analytica chimica acta》1980,122(3):249-256
The merits and demerits of data retrieval and artificial intelligence systems for identifying polyatomic molecules from their molecular spectra are considered. It is concluded that the creation of artificial intelligence systems provides the most promising developments for the future of analytical molecular spectroscopy. In these systems, experimental spectra are compared with computer-generated data in the course of solution of the analytical problem and not with data already stored in the data bank. 相似文献
22.
From the mathematical standpoint, it is possible to reduce a spectral study to the solution of the so-called inverse spectral problems. In practice, the inverse problem is solved through consistent comparison of the spectrum of the model with the experimental spectrum, the degree of closeness between theoretical and experimental spectra providing a quality criterion for the solution. The model may be characterized by different levels of complexity. This paper discusses the course of recent developments in theoretical spectroscopy, the present state-of-the-art, and forecasts future union of experimental and theoretical methods. 相似文献
23.
[reaction: see text] A convenient one-pot synthesis of 4-fluoroquinolinones that are active against KDR kinase is described. The mechanism of the reaction is believed to involve the formation of a quinone methide intermediate. 相似文献
24.
Transient isotopic experiments reveal that the mechanism of N2O formation in the high-temperature NH3 oxidation over Pt-Rh gauze involves the reaction of adsorbed ammonia intermediate species (NHx) and NO. 相似文献
25.
26.
Evgueni Riaplov John P Maier Dietmar Panten Pavel Rosmus 《Journal of Molecular Spectroscopy》2003,222(1):15-21
Mass selected C2S− ions have been co-deposited with neon to grow a matrix at 6 K. The and electronic absorption spectra of the linear CCS− anion have been identified with origin band at 10 606 and 22 273 cm−1, respectively. After exposure to UV radiation a new electronic transition of CCS is observed (origin band at 30 563 cm−1) in addition to its known band system. Ab initio calculations provide support for the symmetry assignment of the upper electronic states of CCS−, CCS and of the vibrational structure in the spectra. 相似文献
27.
The reaction between C3H8 and N2O over steam-activated FeMFI zeolites leads to high yields towards propene (24%) and propionaldehyde (6%) at 773-798 K. 相似文献
28.
L. A. Gribov 《Journal of Applied Spectroscopy》2007,74(4):602-604
We propose an approach to estimating the influence of a strong external electric field on the probability of photochemical
transformations. The approach is based on an analysis of the appearance or disappearance of the resonance levels of interacting
subsystems that are necessary for the chemical transformation and the change of overlap integral of the corresponding wave
functions.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 4, pp. 543–545, July–August, 2007. 相似文献
29.
We study the theory of lovely pairs of geometric structures, in particular o-minimal structures. We use the pairs to isolate a class of geometric structures called weakly locally modular which generalizes the class of linear structures in the settings of SU-rank one theories and o-minimal theories. For o-minimal theories, we use the Peterzil-Starchenko trichotomy theorem to characterize for a sufficiently general point, the local geometry around it in terms of the thorn U-rank of its type inside a lovely pair. 相似文献
30.
The vast numbers of molecular objects and chemical transformations of a substrate cannot be evaluated even intuitively, which necessitates the development of simple reaction monitoring methods. Here this problem is formulated for the first time, and possible solutions are substantiated. 相似文献