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We have investigated the photoluminescence (PL) properties of trace amounts of Pr and Tb in single-crystal samples of yttria-stabilized zironia (YSZ), and found that Pr of the order of 10−6 mass% and Tb of the order of 10−5 mass% in YSZ can be detected by the PL spectroscopy. The PL spectra of the YSZ samples for the 280 nm excitation were comprised of several peaks and a broad emission. The peaks were attributed to transitions of Pr3+ and Tb3+ in the YSZ samples, whereas the broad emission seemed to be attributed to the yttria-associated oxygen vacancies. The peak intensities corresponded to the amounts of Pr and Tb in the YSZ samples, the amounts of which were analyzed by glow discharge mass spectrometry. In the PL excitation spectra, but not in the photoabsorption spectra, small peaks at 376 and 381 nm were observed, and were attributed to the transitions of Tb3+ in the YSZ samples. The results of the PL excitation spectra corresponding to the Pr3+ line emissions suggest that the charge transfer occurs between the YSZ and Pr ion in it. The trace amounts of these lanthanoids in YSZ would disturb the decay process of the photoinduced electrons to the yttria-associated oxygen vacancies. 相似文献
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Ryohei Hanayama Kenichi Hibino Shin’ichi Warisawa Mamoru Mitsuishi 《Optical Review》2004,11(5):337-343
Wavelength scanned interferometry allows the simultaneous measurement of top surface shape and optical thickness variation of a transparent object consisting of several parallel surfaces. Interference signals from these surfaces can be separated in frequency space, and their phases are detected by discrete Fourier analysis. However, these signal frequencies are shifted from the detection frequency by the refractive index dispersion of the object and a nonlinearity of the wavelength scanning. The Fourier analysis is sensitive to the detuning of the signal frequency and suffers from the multiple-beam interference noise. Conventional error-compensating algorithms cannot be applied to an object consisting of more than three reflecting surfaces. We derive a new 2N-1 sample error-compensating algorithm, which allows the phase detection of any order of harmonic frequency among the interference signals. The new algorithm suppresses the effect of signal frequency detuning as well as the multiple-beam interference noise and can be applied to the measurement of complex objects consisting of more than three reflecting surfaces. 相似文献
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Kazuhiko Nakano Toshihiro Nakamura Izumi Nakai Akira Kawase Makoto Imai Mikio Hasegawa Yohichi Ishibashi Isamu Inamoto Kazuhuyu Sudou Masaru Kozaki Akira Tsuruta Akihiro Ono Kazutoshi Kakita Mamoru Sakata 《Analytical sciences》2006,22(9):1265-1268
The Japan Society for Analytical Chemistry has developed some new plastic certified reference materials (CRMs) for the analysis of mercury in polyester disks using XRF analysis. These CRMs (named as JSAC 0621-0625) were prepared by casting polyesters including a toluene solution of organometallic compounds as a standard. Concentrations of the five levels of mercury ranged from 0 to 250 mg/kg. Homogeneity tests of prepared disks had shown excellent results. Interlaboratory comparison study for the certification was performed by 15 laboratory participants. The z-scores in robust statistical method was applied for the evaluation of outliers. The certified values were assigned after discarding outliers. The uncertainties of certified values were determined as the confidence levels of 95%. 相似文献
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The structure of senecicannabine(), a new mcrocyclic pyrrolizidine alkaloid isolated from , has been established by chemical study and X-ray analysis. 相似文献
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Racemic 2-amino-3-(heteroaryl)propanoic acids (1), mostly with a furan or thiophene nucleus as a heteroaryl group, were synthesized in 48-94% yield by the reduction of 3-(heteroaryl)-2-(hydroxyimino)propanoic acids (5) with zinc dust and formic acid in the presence of a catalytic amount of iron dust at 60 degrees C for 2 h. Under these conditions, unfavorable hydrogenolysis of bromine on the thiophene nucleus does not occur. Traditional N-formylation of the prepared 3-(heteroaryl)alanine (1) with a mixture of formic acid and acetic anhydride afforded 2-(formylamino)-3-(heteroaryl)propanoic acids (6) in 51-95% yield. 相似文献
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Tomoya Kinumi Kazuo Tsujimoto Mamoru Ohashi Reiko Hara Tomiyuki Hara Koichi Ozaki Miho Saka Yuko Katsuta Akimori Wada Masayoshi Ito 《Photochemistry and photobiology》1993,58(3):409-412
Abstract— 3, 7-Dimethyl-2, 4, 6, 8, 10-dodecapentaenal was synthesized for reconstitution of the retinochrome analog. Its opsin shift was 1000 cm 1 smaller than that of native retinochrome, whose chromophore contains the same number of double bonds. The conformational change from 6-s-trans to 6-s-cis , as figured in a retinal molecule, plays an important role in the formation of the retinochrome analog, based on the estimation of opsin shifts for retinal analogs locked in the 6-s conformation. Thus the conformation of the 6–7 single bond in the native retinochrome was suggested to be 6 -cis . Analysis of the circular dichroic spectra of retinochrome analogs revealed that the 6-s conformation is independent of the appearance of the β-band. The stereoselectivity in the photoisomerization of the retinal analogs by a retinochrome template depends on the hydrophobic binding in the region of the β-ionone ring. 相似文献