Zobrazeno 1 - 10
of 51
pro vyhledávání: '"Shigeyuki Wakaki"'
Autor:
Andros Daniel Cruz Salmeron, Hideko Takayanagi, Shigeyuki Wakaki, Tsuyoshi Ishikawa, Toshihiro Miyajima, Hitomi Wakaki, Takuya Itaki, Yasufumi Iryu
Publikováno v:
Progress in Earth and Planetary Science, Vol 9, Iss 1, Pp 1-20 (2022)
Abstract We investigated the water-mass structure on the Okinawa Trough and Pacific sides of the southern Ryukyu Island Arc (Yonaguni, Iriomote, and Ishigaki subareas) using the Nd isotope composition (143Nd/144Nd ratios; expressed as εNd values) of
Externí odkaz:
https://doaj.org/article/01b1c68b87dd4901a76a394e8b7dd2d2
Autor:
Shigeyuki Wakaki, Jo Aoki, Ryoya Shimode, Katsuhiko Suzuki, Takashi Miyazaki, Jenny Roberts, Hauke Vollstaedt, Satoshi Sasaki, Yoshitaka Takagai
Publikováno v:
Scientific Reports, Vol 12, Iss 1, Pp 1-10 (2022)
Abstract Strontium-90 is a major radioactive nuclide released by nuclear accidents and discharge waste. Input of such radioactive nuclide into earth surface environment causes potential threat of long-term internal exposure when taken up by organism.
Externí odkaz:
https://doaj.org/article/99bf54e94471476e9e5fb960afea1092
Publikováno v:
Frontiers in Marine Science, Vol 9 (2022)
Stable isotope ratios of Sr (88Sr/86Sr) are a novel indicator for identifying terrestrial and oceanic Sr cycling and biological processes. Here we evaluate the temperature dependence of stable Sr isotope ratios (δ88Sr) in the calcite skeletons of pr
Externí odkaz:
https://doaj.org/article/56de40727ccd4eeaa3280be09b54ec09
Autor:
Kai Nils Nitzsche, Shigeyuki Wakaki, Katsuyuki Yamashita, Ki‐Cheol Shin, Yoshikazu Kato, Hiromitsu Kamauchi, Ichiro Tayasu
Publikováno v:
Ecosphere, Vol 13, Iss 2, Pp n/a-n/a (2022)
Abstract Recent studies showed the potential of stable isotopes of the macronutrient calcium (δ44/40Ca) and nonessential strontium (δ88/86Sr) as new trophic level indicators in terrestrial vertebrates and marine teleost fishes. In this study, we te
Externí odkaz:
https://doaj.org/article/1070426ac3a242d5b87edf7a9349e079
Autor:
Go-Ichiro Uramoto, Yuki Morono, Naotaka Tomioka, Shigeyuki Wakaki, Ryoichi Nakada, Rota Wagai, Kentaro Uesugi, Akihisa Takeuchi, Masato Hoshino, Yoshio Suzuki, Fumito Shiraishi, Satoshi Mitsunobu, Hiroki Suga, Yasuo Takeichi, Yoshio Takahashi, Fumio Inagaki
Publikováno v:
Nature Communications, Vol 10, Iss 1, Pp 1-10 (2019)
Ferromanganese minerals are abundant in marine environments but the extent of these minerals in subseafloor sediments remains unknown. Here the authors find abundant ferromanganese microparticles in oxic pelagic clays, accounting for 14–16% of the
Externí odkaz:
https://doaj.org/article/2cdd5f8e34424f969e7b82419f23116c
Autor:
Shigeyuki Wakaki, Jo Aoki, Ryoya Shimode, Katsuhiko Suzuki, Takashi Miyazaki, Jenny Roberts, Hauke Vollstaedt, Satoshi Sasaki, Yoshitaka Takagai
Publikováno v:
Scientific Reports, Vol 12, Iss 1, Pp 1-1 (2022)
Externí odkaz:
https://doaj.org/article/2e8de8c8187c4c8ba27bfa165c9140eb
Autor:
Toshihiro Yoshimura, Shigeyuki Wakaki, Hodaka Kawahata, H. M. Zakir Hossain, Takuya Manaka, Atsushi Suzuki, Tsuyoshi Ishikawa, Naohiko Ohkouchi
Publikováno v:
Frontiers in Earth Science, Vol 9 (2021)
The Sr isotopic composition of rivers and groundwaters in the Bengal Plain is a major contributor to the global oceanic Sr inventory. The stable strontium isotope ratios (δ88Sr) provide a new tool to identify chemical weathering reactions in terrest
Externí odkaz:
https://doaj.org/article/f7963e65941f4ae19852e93579cb2d75
Autor:
Toshihiro Yoshimura, Shigeyuki Wakaki, Tsuyoshi Ishikawa, Toshitaka Gamo, Daisuke Araoka, Naohiko Ohkouchi, Hodaka Kawahata
Publikováno v:
Frontiers in Earth Science, Vol 8 (2020)
Variations in the stable isotopic composition of seawater Sr (δ88Sr) is a new tool for estimating the rates of global carbonate sedimentation over geologic time, yet the isotope compositions of the major sources and sinks of Sr to the world oceans a
Externí odkaz:
https://doaj.org/article/1b110adff85a4672bcf076e4b15f195c
Autor:
Otabek Ulugbek Ogli Anvarov, Yoshihito Kamata, Teruyuki Maruoka, Junichiro Kuroda, Shigeyuki Wakaki, Ken-ichiro Hisada
Publikováno v:
Geosciences, Vol 12, Iss 5, p 203 (2022)
Lithostratigraphy and isotopes of Paleogene sequences consisting mainly of terrestrial clastics and limestone were examined in the northern Fergana Basin of Uzbekistan. The studied sections consisted of two facies: the lower sequence coarse-grained t
Externí odkaz:
https://doaj.org/article/c6d6bdcbb38640538affc41353dc51cc
Autor:
Akira Ijiri, Naotaka Tomioka, Shigeyuki Wakaki, Harue Masuda, Katsumi Shozugawa, Sunghan Kim, Boo-Keun Khim, Masafumi Murayama, Motoyuki Matsuo, Fumio Inagaki
Publikováno v:
Frontiers in Earth Science, Vol 6 (2018)
Widespread diagenesis of clay minerals occurs in deeply buried marine sediments under high-temperature and high-pressure conditions. For example, the smectite-to-illite (S-I) transformation has been often observed in sediments at in situ temperatures
Externí odkaz:
https://doaj.org/article/c783bded4eb74146acecccdf708c216e