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61.
Yoshiaki Hamada Masamichi Tsuboi Munetaka Nakata Mitsuo Tasumi 《Journal of Molecular Spectroscopy》1984,106(1):164-174
Infrared absorption spectra of allylamine and its amino-deuterated species were observed in the gas phase and in the low-temperature Ar matrix. An analysis of the spectra showed that there exist mainly three rotational conformers, and possibly one other conformer as a minor component. At room temperature, the skew forms around the CC bond populate about 70%, while the rest are assigned to the cis form(s). On the other hand, two forms around the CN bond, gauche and trans, exist with about equal populations. 相似文献
62.
The absorption cross-section integral and the oscillator strength of the 960 nm absorption band due to F2
– colour centres in LiF crystal is determined at room temperature from the absorption cross-section spectrum of the F2
– centres obtained from saturable absorption studies. A comparison with previous results is made. 相似文献
63.
T. Tsuboi 《Physics letters. A》1984,102(3):138-140
The temperature dependence of the absorption intensity of hot magnon sidebands is investigated for the two-dimensional (2D) antiferromagnet BaMnF4, and the 3D antiferromagnet MnF2. A general expression for the temperature dependence is presented for 1D, 2D and 3D antiferromagnets. 相似文献
64.
A partial map f of a structure M is called almost total if |M — dom(f)| = |M — ran(f)| < ω. We study a difference between an almost total elementary map and an automorphism. 相似文献
65.
LiF crystals with F2
- centers contain a whole series of F-based colour centers with spectrally overlapping absorption spectra. On the short-wavelength side the absorption spectrum of the F2
- centers is overlapping with the absorption spectra of other colour centers and is therefore not directly accessible by transmission measurements. Fluorescence excitation spectroscopy is employed here to gain information on the absorption spectrum of F2
- centers in spectral regions where the absorption by other centers is present. The fluorescence signal emitted beyond 1200 nm is detected as a function of the excitation wavelength in the range from 350 nm to 1100 nm. The F2
- center absorption cross-section spectrum in the wavelength range from 690 nm to 1100 nm and from 350 nm to 410 nm is determined from the fluorescence excitation quantum distribution and the transmission spectrum. Influences of fluorescence re-absorption and Förster-type energy transfer on the fluorescence excitation quantum distribution and the subsequent F2
- center absorption cross-section determination are discussed. PACS 61.72.Ji; 78.40.Ha; 78.55.Fv 相似文献
66.
67.
The epoxide 1 obtained by the Darzens condensation reaction of aldehydes with methyl dichloroacetate, reacted with aromatic compounds in the presence of aluminium chloride to afford α-aryl-β-chloro-α-hydroxyalkanoate 3. The intra-molecular nucleophilic addition of epoxide 1′ gave cyclisation compound 4. The scope and limitation of these reaction were studied for various aldehydes and aromatic compounds. The reaction was also studied in the presence of aluminium chloride supported on alumina or silica gel, which is thought to be a mild Lewis acid and harmless for environment. 相似文献
68.
Tatsuya Hattori Riadh Sahnoun Hideyuki Tsuboi Akira Endou Momoji Kubo Akira Miyamoto 《Applied Surface Science》2008,254(23):7929-7932
We developed a novel computational method to investigate the influences of the microstructure of the polymer electrolyte fuel cell cathode catalyst layer on the overpotential characteristic toward its optimization. Three-dimensional cathode catalyst layer models were constructed by applying three-dimensional porous structure simulator and developed simulator was used to study the overpotential characteristics. Our results showed that the overpotential decreased as decrease of the standard deviation of the ionomer thickness distribution due to the increase of number of active sites. 相似文献
69.
Science China Chemistry - Albeit their high efficiencies, the operational stability of the organic light emitting diodes (OLEDs) based on thermally activated delayed fluorescence (TADF) emitters is... 相似文献
70.
We introduce a new construction of real closed fields by using an elementary extension of an ordered field with an integer part satisfying . This method can be extend to a finite extension of an ordered field with an integer part satisfying . In general, a field obtained from our construction is either real closed or algebraically closed, so an analogy of Ostrowski's dichotomy holds. Moreover we investigate recursive saturation of an o‐minimal extension of a real closed field by finitely many function symbols. 相似文献