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A linear correlation between the NQR frequency of the terminal iodine atom and the corresponding I-I bond length in I3? was found in several compounds containing triiodide anions. A simple extended Huckel MO calculation suggested that such a correlation can be used to check the validity of wavefunctions of iodine. 相似文献
45.
The structure of the sensing element of a gold-deposited optical fiber sensor was simplified and quantitative analyses of various alcohols with the sensor showed improvement of the performance. The sensor uses surface plasmon resonance (SPR) at the interface of a sample solution and a thin (10 - 70 nm) gold film deposited on half of the exposed core of the optical fiber. The sensor with a film thickness of 45 nm can detect a small change of 5.6 x 10(-5) refractive index (RI) units in the refractivity. The response time is less than 0.5 min and the relative standard deviation for measurements is less than or equal to 1%. A straight line with a correlation coefficient of 0.9995 was obtained below 10%, v/v in the calibration curve for methanol solutions of benzyl alcohol. The minimum of the response curve due to the maximum excitation of SPR in the refractivity range from 1.33 to 1.44 RI units shifts to a lower refractivity as the film becomes thicker. The response curves of the sensors were calculated from SPR theoretical equations while considering of the distribution in the thickness of the deposited gold films. The improvement in the performance of the sensor is discussed. 相似文献
46.
H. Oda M. Akiyama T. Masuda T. Nakamura 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(2):439-442
We measured radiocarbon age of an ancient document “Minamoto no Yoritomo Sodehan Migyosho”. The content tells that it was
issued in 1189 by “Minamoto no Yoritomo” known as the virtually first shogun in Japan to grant “Matsugi” family the privilege
of controlling craftsmen of foundry industry. Paleographical views, however, suggested that it can be a counterfeit. The radiocarbon
dating clarified that the document was written not in the 12th but after the 16th century. 相似文献
47.
Tanaka M Nakamura M Ikeda T Ikeda K Ando H Shibutani Y Yajima S Kimura K 《The Journal of organic chemistry》2001,66(21):7008-7012
Synthetic procedures for monoazathiacrown ethers were explored, and monoazatrithia-12-crown-4, monoazatetrathia-15-crown-5, and monoazapentathia-18-crown-6 were obtained in moderate yields by the reaction of bis(2-chloroethyl)amine with the appropriate dithiols in the presence of lithium hydroxide in THF. To evaluate metal-ion binding properties of the monoazathiacrown ethers by solvent extraction, lipophilic dodecyl and dodecanoyl groups were incorporated onto the monoazathiacrown ethers. The solvent extraction experiments suggested that monoazathiacrown ethers have Ag(+) and Hg(2+) selectivities and that the relative selectivity between Ag(+) and Hg(2+) depends on their nitrogen atom properties and numbers of sulfur atoms reflecting the respective affinities of nitrogen and sulfur atoms to Hg(2+) and Ag(+). An interesting ability to bind Mg(2+) was observed in the case of N-dodecyl monoazatrithia-12-crown-4. 相似文献
48.
Atsushi Ikeda Masaru Kawaguchi Yoshio Suzuki Tsukasa Hatano Munenori Numata Seiji Shinkai Akio Ohta Makoto Ohta 《Journal of inclusion phenomena and macrocyclic chemistry》2000,38(1-4):163-170
The calixarene-fullerene interaction,which causes only a slight change in the absorptionspectra, has been substantiated by calorimetricmeasurements: the H° values arecomparable with those obtained from the associationconstants estimated by a spectroscopic method. Furthermore, we determined the association constantbetween homooxacalix[3]arene and [60]fullerenederivatives with a porphyrin moiety by fluorescencespectra. 相似文献
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The INDO calculations were performed on the three azines: pyridazine, pyrimidine, and pyrazine. The cannonical molecular orbitais obtained by these calculations were then transformed into the localized molecular orbitals. With the use of the localized molecular orbitals, the variation in the lone-pair orbital energies of these molecules were pursued in the light of the through-space and/or the through-bond interactions between the specified localized molecular orbitals in a molecule selectively. The interactions were expressed by the summation of several terms: through-space, through-bond, through-virtuals and coupling terms. 相似文献