Search

Your search keyword '"Kubo, Atsushi"' showing total 10 results
Start Over Author "Kubo, Atsushi" Publication Year Range This year
10 results on '"Kubo, Atsushi"'

6. A global database of dissolved organic matter (DOM) concentration measurements in coastal waters (CoastDOM v1)

Author

Lønborg, Christian, Carreira, Cátia, Abril, Gwenaël, Agustí, Susana, Amaral, Valentina, Andersson, Agneta, Arístegui, Javier, Bhadury, Punyasloke, Bif, Mariana B., Borges, Alberto V., Bouillon, Steven, Calleja, Maria Ll., Cotovicz Jr., Luiz C., Cozzi, Stefano, Doval, Maryló, Duarte, Carlos M., Eyre, Bradley, Fichot, Cédric G., García-Martín, E. Elena, Garzon-Garcia, Alexandra, Giani, Michele, Gonçalves-Araujo, Rafael, Gruber, Renee, Hansell, Dennis A., Hashihama, Fuminori, He, Ding, Holding, Johnna M., Hunter, William R., Ibánhez, J. Severino P., Ibello, Valeria, Jiang, Shan, Kim, Guebuem, Klun, Katja, Kowalczuk, Piotr, Kubo, Atsushi, Lee, Choon-Weng, Lopes, Cláudia B., Maggioni, Federica, Magni, Paolo, Marrase, Celia, Martin, Patrick, McCallister, S. Leigh, McCallum, Roisin, Medeiros, Patricia M., Morán, Xosé Anxelu G., Muller-Karger, Frank E., Myers-Pigg, Allison, Norli, Marit, Oakes, Joanne M., Osterholz, Helena, Park, Hyukyung, Lund Paulsen, Maria, Rosentreter, Judith A., Ross, Jeff D., Rueda-Roa, Digna, Santinelli, Chiara, Shen, Yuan, Teira, Eva, Tinta, Tinkara, Uher, Guenther, Wakita, Masahide, Ward, Nicholas, Watanabe, Kenta, Xin, Yu, Yamashita, Youhei, Yang, Liyang, Yeo, Jacob, Yuan, Huamao, Zheng, Qiang, Álvarez-Salgado, Xosé Antón, Lønborg, Christian, Carreira, Cátia, Abril, Gwenaël, Agustí, Susana, Amaral, Valentina, Andersson, Agneta, Arístegui, Javier, Bhadury, Punyasloke, Bif, Mariana B., Borges, Alberto V., Bouillon, Steven, Calleja, Maria Ll., Cotovicz Jr., Luiz C., Cozzi, Stefano, Doval, Maryló, Duarte, Carlos M., Eyre, Bradley, Fichot, Cédric G., García-Martín, E. Elena, Garzon-Garcia, Alexandra, Giani, Michele, Gonçalves-Araujo, Rafael, Gruber, Renee, Hansell, Dennis A., Hashihama, Fuminori, He, Ding, Holding, Johnna M., Hunter, William R., Ibánhez, J. Severino P., Ibello, Valeria, Jiang, Shan, Kim, Guebuem, Klun, Katja, Kowalczuk, Piotr, Kubo, Atsushi, Lee, Choon-Weng, Lopes, Cláudia B., Maggioni, Federica, Magni, Paolo, Marrase, Celia, Martin, Patrick, McCallister, S. Leigh, McCallum, Roisin, Medeiros, Patricia M., Morán, Xosé Anxelu G., Muller-Karger, Frank E., Myers-Pigg, Allison, Norli, Marit, Oakes, Joanne M., Osterholz, Helena, Park, Hyukyung, Lund Paulsen, Maria, Rosentreter, Judith A., Ross, Jeff D., Rueda-Roa, Digna, Santinelli, Chiara, Shen, Yuan, Teira, Eva, Tinta, Tinkara, Uher, Guenther, Wakita, Masahide, Ward, Nicholas, Watanabe, Kenta, Xin, Yu, Yamashita, Youhei, Yang, Liyang, Yeo, Jacob, Yuan, Huamao, Zheng, Qiang, and Álvarez-Salgado, Xosé Antón

Abstract

Measurements of dissolved organic carbon (DOC), nitrogen (DON), and phosphorus (DOP) concentrations are used to characterize the dissolved organic matter (DOM) pool and are important components of biogeochemical cycling in the coastal ocean. Here, we present the first edition of a global database (CoastDOM v1; available at https://doi.org/10.1594/PANGAEA.964012, Lønborg et al., 2023) compiling previously published and unpublished measurements of DOC, DON, and DOP in coastal waters. These data are complemented by hydrographic data such as temperature and salinity and, to the extent possible, other biogeochemical variables (e.g. chlorophyll a, inorganic nutrients) and the inorganic carbon system (e.g. dissolved inorganic carbon and total alkalinity). Overall, CoastDOM v1 includes observations of concentrations from all continents. However, most data were collected in the Northern Hemisphere, with a clear gap in DOM measurements from the Southern Hemisphere. The data included were collected from 1978 to 2022 and consist of 62 338 data points for DOC, 20 356 for DON, and 13 533 for DOP. The number of measurements decreases progressively in the sequence DOC > DON > DOP, reflecting both differences in the maturity of the analytical methods and the greater focus on carbon cycling by the aquatic science community. The global database shows that the average DOC concentration in coastal waters (average ± standard deviation (SD): 182±314 µmol C L−1; median: 103 µmol C L−1) is 13-fold higher than the average coastal DON concentration (13.6±30.4 µmol N L−1; median: 8.0 µmol N L−1), which is itself 39-fold higher than the average coastal DOP concentration (0.34±1.11 µmol P L−1; median: 0.18 µmol P L−1). This dataset will be useful for identifying global spatial and temporal patterns in DOM and will help facilitate the reuse of DOC, DON, and DOP data in studies aimed at better characterizing local biogeochemic

Published
2024

8. Molecular dynamics study of thermal transport at interface between alumina and epoxy resin.

Author

Umeno, Yoshitaka, Kubo, Atsushi, Kurata, Yuto, Sakaniwa, Daisuke, Ishikawa, Fumiaki N., and Yamaguchi, Kenji

Subjects
*MOLECULAR dynamics, *SILANE coupling agents, *THERMAL resistance, *HEAT transfer, *THERMAL conductivity, *EPOXY resins
Abstract

The study investigates heat transfer within a composite consisting of epoxy resin and alumina filler using all-atom molecular dynamics simulations. Various models of epoxy resin–alumina filler interfaces were analyzed, both with and without silane coupling agents (SCAs), to assess thermal conductivity and resistance. The results reveal that the presence of SCAs enhances heat transfer at the resin/filler interface. Conversely, models lacking SCAs exhibit a distinct temperature gap, indicating thermal resistance. In addition, the study suggests that effective heat transfer in polymer composites is influenced not only by molecular coupling at interfaces but also by the alignment of resin polymers. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

9. Exploring Coupled Plasmonic Nanostructures in the Near Field by Photoemission Electron Microscopy

Author

Yu, Han, Sun, Quan, Ueno, Kosei, Oshikiri, Tomoya, Kubo, Atsushi, Matsuo, Yasutaka, and Misawa, Hiroaki

Abstract

The extraordinary optical properties of coupled plasmonic nanostructures make these materials potentially useful in many applications; thus, they have received enormous attention in basic and applied research. Coupled plasmon modes have been characterized predominantly using far-field spectroscopy. In near-field spectroscopy, the spectral response of local field enhancement in coupled plasmonic nanostructures remains largely unexplored, especially experimentally. Here, we investigate the coupled gold dolmen nanostructures in the near field using photoemission electron microscopy, with wavelength-tunable femtosecond laser pulses as an excitation source. The spatial evolution of near-field mapping of an individual dolmen structure with the excitation wavelength was successfully obtained. In the near field, we spatially resolved an anti-bonding mode and a bonding mode as the result of plasmon hybridization. Additionally, the quadrupole plasmon mode that could be involved in the formation of a Fano resonance was also revealed by spatially resolved near-field spectra, but it only contributed little to the total near-field enhancement. On the basis of these findings, we obtained a better understanding of the near-field properties of coupled plasmonic nanostructures, where the plasmon hybridization and the plasmonic Fano resonance were mixed.

Published
2024
Full Text
View/download PDF

10. Dislocation random walk under cyclic deformation.

Author

Kubo A, Kawai E, Sumigawa T, Shima H, and Umeno Y

Abstract

Dislocation motion under cyclic loading is of great interest from theoretical and practical viewpoints. In this paper, we develop a random walk model for the purpose of evaluating the diffusion coefficient of dislocation under cyclic loading condition. The dislocation behavior was modeled as a series of binomial stochastic processes (one-dimensional random walk), where dislocations are randomly driven by the external load. The probability distribution of dislocation motion and the diffusion coefficient per cycle were analytically derived from the random-walk description as a function of the loading condition and the microscopic material properties. The derived equation was validated by comparing the predicted diffusion coefficient with the molecular dynamics simulation result copper under cyclic deformation. As a result, we confirmed fairly good agreement between the random walk model and the molecular dynamics simulation results.

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results