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101.
The modern intracavity laser method has been applied to study electronic spectra of the hafnium monohalides molecules. Results of new investigation of HfF and HfBr molecules are presented: the bands at 589.3, 590.6, and 593.1 nm observed in intracavity laser spectra of HfF4 have been assigned to the bands of HfF or ionized HfF; new molecular constants of the HfBr molecule have been obtained. Spectroscopic studies of HfCl and Hfl molecules are discussed, and the most reliable molecular constants of HfCl, HfBr, and Hfl molecules are recommended. 相似文献
102.
Polarized spectra of biological molecules oriented in artificial systems can give useful information of structural and spectroscopical properties of these molecules1,2. Such investigations have been carried out recently for several biological systems: chlorophylls3, 4, 5, 6, 7, carotenoids8, biliproteins9, 10, bacterial reaction centers11, 12, bacteriochlorophylls13 etc. 相似文献
103.
Die Gammaspektren von Radionuklidgemischen, die als Folge der Folge der momentanen Spaltung von235 U mit thermischen Neutronen, 235U und 239 Pu mit Spaltneutronen und 238 U mit 14-MeV -Neutronen entstehen, wurden berechnet. Die Angaben über Zerfallsreihen, Spaltausbeuten, Halbwertszeiten und Nuklidgammaspektren für etwa 200 Radionuklide basieren vol allem auf einer Zusammenstellung von Davies. Es sind die Gammaspektren, die Gammaemissionsraten, die Expositionsdosisleistungen und die mittleren Energien für ein Alter der Spaltproduktgemische von einer Minute bis zu 100 Jahren angegeben. 相似文献
104.
《光谱学快报》2013,46(5):647-663
The normal coordinate analysis of the title complex, 1,2-bis(2-formylglycinebenzenesulfenyl) ethane Pd(II) dichloride has been carried out by using the Urey-Bradley force field. According to the molecular structure determined by x-ray crystallographic analysis, 182 internal coordinates were established and 112 theoretical vibration frequencies agree well with the observed values with the average difference of 2.53 cm?1 and the maximum deviation of 16.0 cm?1. 相似文献
105.
Two protonated forms of chlorine nitrate, HClONO+ 2 and ClONO2H+, are treated ab initio by the Hartree-Fock and the second order Møller-Plesset perturbation approach with the standard 6–31G* basis set. Both minimum energy structures are planar (C 3 symmetry) and their structural, energy, and vibrational parameters are reported. The computations conclude that the proton attacks the chlorine nitrate at its central, not end, oxygen atom. The protonation causes a considerable elongation of the central ON bond which becomes most probable place of cleavage. The dissociation should yield the neutral HOCl and NO+ 2. These quantum-chemical findings well agree with the previous experimental indications. 相似文献
106.
C-13 and H-1 NMR spectra of some 1-(4′-dimethylaminobenzylideneamino)pyridinium perchlorates show that the angle of twist of the pyridine ring in unsubstituted, 1, and 2-alkyl substituted compounds 2–5 is comparable. However, it is considerably increased in 2,6-dialkyl derivatives. As seen from the spectral data, pyridine and phenyl rings in 2,6-diphenyl derivative 15 are not coplanar. The effect of 4-alkyl substituent is of hyperconjugative chacter. In general, the amount of the positive charge at C-4 in 2,6-dialkyl substituted salts is higher as compared to 2-monosubstituted compounds. 相似文献
107.
Frequencies of absorption band maxima for the first two electronic singlet transitions of coronene, triphenylene and 1,2,5,6-dibenzanthracene in vapor phase were calculated indirectly from solution spectral data. The calculations were based on two different models: the first one was a linear correlation between the solution absorption frequencies in nonpolar solvents and the solvent refractive indices. The accuracy of both methods was checked with anthracene and some of its derivatives: both methods gave a good agreement with the experimental values. 相似文献
108.
A. M. El-Agramy B. A. Henaish A. A. Shabaka 《Isotopes in environmental and health studies》2013,49(10):479-482
Radiophotolumenescence (RPL) of irradiated and non irradiated thin films of polymethylmethacrylate (PMMA) doped with anthracene (Anth) as a donor, and tetracyanoquinodimethane (TCNQ) as an acceptor, has been investigated. The RPL – glow spectrum was recorded to study the characterizing emission bands from the point of view of glow peak position and intensity and hence the prospective relative sensitivities. RFL – signal fading after one month storage in dark at room temperature post gamma irradiation was also studied. PMMA doped with 6:4 donor to acceptor ratio has been proved to be the most sensitive one with less fading regarding gamma detection. On the other hand 2 Anth: 8 TCNQ was found to be the proper dopant concentration ratio for thermal neutron detection. 相似文献
109.
B. Lorenz R. Kirmse M. Findeisen K. Schmidt 《Isotopes in environmental and health studies》2013,49(1):125-130
Abstract The reaction of 2-pyridine carboxylic acid (Hpic) with (n-Bu4N)[TcNCl4] and (n-Bu4N)[TcOCl4] in ethanol and methanol, respectively, yields the dinuclear μ-oxo complex [(pic)2NTc-O-TcN(pic)(Hpic)Cl] and the monomeric complex [TcO(pic)2Cl]. Visible and infrared spectroscopy, ESR, 1H-NMR and 99Tc-NMR have been used to characterize the new compounds. The most important field of application for the new compounds synthesized is radiodiagnostics. 相似文献
110.
In this paper, β -Cyclodextrin (β -CD) was used to study the interaction of berberine with DNA by the means of absorption spectrum and fluorescence spectrum. Experimental results showed that it was the isoquinolinic part that intercalated into the DNA double helix. And the value of the intrinsic binding constant K was 4.5 × 103l/mol in the presence of β -CD and 1.1 × 104l/mol in the absence of β -CD. 相似文献