著者

Nakayama K. Sato T. Dobashi T. Terashima K. Souma S. Matsui H. Takahashi T. Campuzano J. C. Kudo K. Sasaki T. Kobayashi N. Kondo T. Takeuchi T. Kadowaki K. Kofu M. Hirota K.

出版者

American Physical Society

雑誌

Physical review B (ISSN:10980121)

巻号頁・発行日

vol.74, pp.054505, 2006-08

被引用文献数

26

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We have performed systematic angle-resolved photoemission spectroscopy (ARPES) on single-layered cuprate superconductor Bi2Sr2CuO6+delta to elucidate the origin of shadow band. We found that the shadow band is exactly the c(2×2) replica of the main band irrespective of the carrier concentration and its intensity is invariable with respect to temperature, doping, and substitution constituents of block layers. This result rules out the possibility of antiferromagnetic correlation and supports the structural origin of shadow band. ARPES experiments on optimally doped La1.85Sr0.15CuO4 also clarified the existence of the c(2×2) shadow band, demonstrating that the shadow band is not a unique feature of Bi-based cuprates. We conclude that the shadow band is related to the orthorhombic distortion at the crystal surface.

著者

Yamada R. Tao G. Zheng J. KOJIMA R. FUJIKAWA Y. SASAKI T. 工藤 章

出版者

環境技術学会

雑誌

環境技術 = Environmental conservation engineering (ISSN:03889459)

巻号頁・発行日

vol.28, no.12, pp.931-939, 1999-12-20

参考文献数

51

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Studies on ice cores drilled in Antarctic, Greenland and Canadian Arctic ice caps provide the environmental composition and the climate in the past. This information and further study will help in the understanding of the basic natural processes and the extent of human impact on the environment and climate. This will eventually enable us to predict the future of the environment. This review summarizes the state of the art methodologies used in ice core studies, with highlights on the recent studies in this group.

著者

Furuya H. Idemitsu K. Inagaki Y. Arima T. Sasaki T. Kuroda Y. Uchikawa S. Mitsugashira S. Suzuki Y.

出版者

東北大学

雑誌

Science reports of the Research Institutes, Tohoku University. Ser. A, Physics, chemistry and metallurgy (ISSN:00408808)

巻号頁・発行日

vol.45, no.1, pp.89-91, 1997-03-28

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It is necessary to obtain the data of some parameters concerning migration behavior of radionuclides in underground water for the safety assessment of radioactive waste disposal. Sorption and desorption experiments were carried out by using tracer amount of plutonium on biotite in a granitic rock. In this study, pH dependence of distribution coefficients of plutonium on a biotite mineral were measured. The following results are obtained; (1) The biotite has the pH buffer capacity at around pH 5. (2) Plutonium sorption rate was fast around pH 6 but slow at lower pH than 5. (3) The 95 percent of plutonium was sorbed on biotite at around pH 5. (4) The 10 to 30 percent of sorbed plutonium in biotite was desorbed with 1N KCl, the 50 to 60 percent with 1N HN0_3. (5) The rest of plutonium sorbed in biotite could not be desorbed even with 1N HN0_3. (6) The neutral plutonyl hydroxide could be an important species sorbed on the biotite.sorptionplutoniumbiotite