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51.
52.
T. Omori K. Omori C. Ochi K. Yoshihara M. Yagi 《Journal of Radioanalytical and Nuclear Chemistry》1984,82(1):61-69
In order to produce routinely carrier-free96Tc and111In, their simultaneous production was examined by means of the stacked foil method. Both niobium and silver foils were arranged on the target holder so as the desired nuclear reactions took place effectively. Simultaneous irradiation of the target with 35 MeV -particles produced effectively111In and96Tc by the109Ag(, 2n)111In and93Nb(, n)96Tc reactions, respectively. Sufficient amounts of radioactivities for tracer uses are obtained by the irradiation at 5 A current for 2 hrs. In addition, carrier-free96TcO4
– in a perchloric acid solution could be prepared by the combined use of precipitation and anion-exchange methods. Separation of carrier-free111In from the silver matrix was done by means of solvent extraction using acetylacetone as a chelating agent. 相似文献
53.
A. Yoshioka K. Nomura M. Takeya K. Shimura K. Masumoto M. Yagi 《Journal of Radioanalytical and Nuclear Chemistry》1988,122(1):175-182
Determination of carbon in copper has been studied by photon activation analysis using 30 MeV bremsstrahlung. Chemical separation of carbon as CO2 was performed by the combustion method in a high flow rate of oxygen stream. It has been demonstrated that the trace amount of carbon in copper can be determined accurately and precisely, and that the detection limit is 0.02 g. 相似文献
54.
Mikio Yagi Nobuyuki Nishi Minoru Kinoshita Saburo Nagakura 《Chemical physics letters》1976,39(2):240-244
Using microwave induced delayed phosphorescence techniques we determined the populating and depopulating rate constants for the individual spin-sublevels of the phosphorescent states of tetracyanobenzene (TCNB) and its charge-transfer complexes with benzene and hexamethylbenzene (HMB) in n-hexane at 1.25 K. It was shown that the non-radiative decay process from the shortest lifetime sublevel is most responsible for the previously observed shortening in the phosphorescence lifetime of the TCNBHMB complex. 相似文献
55.
Photochemical nitrosation of phenol in aqueous nitrite solution 总被引:1,自引:0,他引:1
56.
Intermolecular charge-transfer phosphorescence and fluorescence were observed for the biphenyl single crystal containing 1, 2, 4, 5-tetracyanobenzene as a guest. In addition, the delayed charge-transfer fluorescence due to triplet-triplet annihilation was observed for the first time. 相似文献
57.
Y. Sakisaka T. Komeda T. Miyano M. Onchi S. Masuda Y. Harada K. Yagi H. Kato 《Surface science》1985,164(1):220-234
Angle-resolved photoemission spectroscopy utilizing synchrotron radiation has been used to study the band structure of the c(2×2) and (3×1) oxygen overlayers on Fe(110). The symmetries of the O-2p-derived states at the center of the surface Brillouin zone were identified using polarized light. At the pxpy- and pz-derived levels are at about 5.5 and 7.0 eV below the Fermi level, respectively, for both ordered overlayers. The p-states of the c(2×2)-O structure show very little dispersion (?0.1 eV) with . On the other hand, the c(3×1)-O overlayer exhibits considerable dispersion of ~1.6 eV. The essential features of the measured dispersion are reproduced well by the dispersion predicted in a qualitative way for an isolated c(3×1) oxygen monolayer. 相似文献
58.
By applying a microwave magnetic field parallel to an external magnetic field, ESR of naphthalene, quinoxaline, quinoline and isoquinoline in their phosphorescent triplet states has been studied at 77 K. The proton hyperfine structures in the Δm = ± 2 transitions were distinctly resolved, especially when the stretched film was used as a host, compared with observations in ethanol glasses. The assignment of these ESR signals was carried out with the aid of the stretched-film method. 相似文献
59.
M. Matoba M. Hyakutake S. Nakamura T. Katayama T. Tonai K. Yagi K. Sato Y. Aoki 《Physics letters. [Part B]》1973,44(2):159-160
In the (p,p′) reaction on 130Te, strong excitation of the second 3? state was found at 3.36±0.01 MeV excitation energy. No strong second 3? state was observed in the (p,p′) reaction on 126Te. 相似文献
60.
Susumu Nakashima Masakazu Yagi Michio Zenki Akinori Takahashi Kyoji Tôei 《Fresenius' Journal of Analytical Chemistry》1984,319(5):506-509
Summary Nitrate was determined in natural water samples by flow-injection spectrophotometry. It was reduced to nitrite with copperized cadmium and the nitrite thus produced reacted with p-aminoacetophenone and m-phenylenediamine. The limit of detection was about 1.5 g l–1 for sample injections of 650 l. The sampling rate was about 40 samples h–1 and the relative standard deviation was above 1% for 0.1–0.3 mg l–1 nitratenitrogen. Nitrite present in the sample was determined separately and subtracted.
Nitratbestimmung in natürlichen Wässern mit Hilfe der Fließinjektions-Analyse
Zusammenfassung Nitrat wird bei dieser Methode mit Hilfe einer Cu/Cd-Reduktionssäule zu Nitrit reduziert, das mit p-Aminoacetophenon und m-Phenylendiamin zur Reaktion gebracht wird. Die gebildete Verbindung wird spektral-photometrisch gemessen. Die Nachweisgrenze beträgt etwa 1,5 g/l bei injizierten Probevolumina von 650 l. Der Probendurchsatz beträgt 40/h. Die relative Standardabweichung liegt über 1% bei 0,1–0,3 mg/l Nitrat-Stickstoff. Vorhandenes Nitrit wird gesondert bestimmt und abgezogen.相似文献