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61.
The binary skutterudite CoP(3) has a large void at the body-centered site of each cubic unit cell and is, therefore, called a nonfilled skutterudite. We investigated its room-temperature compression behavior up to 40.4 GPa in helium and argon using a diamond-anvil cell. High-pressure in situ X-ray diffraction and Raman scattering measurements found no phase transition and a stable cubic structure up to the maximum pressure in both media. A fitting of the present pressure-volume data to the third-order Birch-Murnaghan equation of state yields a zero-pressure bulk modulus K(0) of 147(3) GPa [pressure derivative K(0)' of 4.4(2)] and 171(5) GPa [where K(0)' = 4.2(4)] in helium and argon, respectively. The Gru?neisen parameter was determined to be 1.4 from the Raman scattering measurements. Thus, CoP(3) is stiffer than other binary skutterudites and could therefore be used as a host cage to accommodate large atoms under high pressure without structural collapse. 相似文献
62.
Preparation of Cu2ZnSnS4 thin films by hybrid sputtering 总被引:2,自引:0,他引:2
Tooru Tanaka Takeshi Nagatomo Mitsuhiro Nishio Akihiro Wakahara Hiroshi Ogawa 《Journal of Physics and Chemistry of Solids》2005,66(11):1978-1981
In order to fabricate Cu2ZnSnS4 thin films, hybrid sputtering system with two sputter sources and two effusion cells is used. The Cu2ZnSnS4 films are fabricated by the sequential deposition of metal elements and annealing in S flux, varying the substrate temperature. The Cu2ZnSnS4 films with stoichiometric composition are obtained at the substrate temperature up to 400 °C, whereas the film composition becomes quite Zn-pool at the substrate temperature above 450 °C. The Cu2ZnSnS4 film shows p-type conductivity, and the optical absorption coefficient and the band gap of the Cu2ZnSnS4 film prepared in this experiment are suitable for fabricating a thin film solar cell. 相似文献
63.
S. Kataoka Y. Tarumi H. Yagi S. Tomiyoshi T. Nozaki 《Journal of Radioanalytical and Nuclear Chemistry》1997,216(2):217-219
Boron and carbon on the surface of silicon wafers in ordinary atmospheres were measured by activation with the10B(d,n)11C and12Cd(d,n)13N reaction, respectively. Two sample plates in intimate contact were bombarded by deuterons, and the11C or13N formed at the inside surfaces were measured after chemical separation. From 1.2·1013 to 8.4·1013 atoms/cm2 of boron and from 2.4·1014 to 6.1·1015 atoms/cm2 of carbon were found ,and the sensitivity was extended down to 5·1012 and 3·1012 atoms/cm2 for boron and carbon, respectively. 相似文献
64.
65.
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
66.
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
67.
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
68.
Photochemical nitrosation of phenol in aqueous nitrite solution 总被引:1,自引:0,他引:1
69.
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
70.
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