Bulletin of the Society of Sea Water Science, Japan
Online ISSN : 2185-9213
Print ISSN : 0369-4550
ISSN-L : 0369-4550
Search
Advanced search
OR
Browse
Search
Volume 74, Issue 3
Displaying 1-13 of 13 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
Preface
Preprint of The 71th Annual Meeting
Original Paper
  • Boron Isotope Fractionation Accompanying Formation of Calcium Borate Minerals at 25 ℃
    Shoko HATTORI, Yoshikazu KIKAWADA, Takao OI
    2020 Volume 74 Issue 3 Pages 176-183
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.3_176
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    Laboratory experiments in which calcium borate minerals were precipitated by water evaporation from aqueous boron and calcium ion-bearing solutions were carried out at 25 ℃ and boron isotope fractionation accompanying the mineral formation was studied. Nobleite and gowerite were obtained as calcium borate minerals, and isotopic analysis was carried out on nobleite. The 11B/10B isotopic ratio of the mineral was smaller than that of the solution, which meant that the heavier isotope 11B was preferentially fractionated into the solution phase. The boron isotopic data of nobleite were sufficiently harmonized with those of borax （sodium borate mineral） and K2［B4O5（OH）4］·2H2O （potassium borate mineral）. The three minerals have the same BO3/BO4 ratio, the ratio of the number of the BO3 triangle units to the number of the BO4 tetrahedron units in the polyborate anion of the structural formula of the mineral. The present study thus reconfirmed and extended the claim that the boron isotope fractionation strongly depends on the BO3/BO4 ratio and is nearly independent of the counter cation.
    View full abstract
    Download PDF (933K)
Note
  • Fundamental Study on Conversion of Ammonium Sulfate to Ammonia Solution by Bipolar Membrane Electrodialysis
    Hiroshi TAKAHASHI, Kazuki FUJITA
    2020 Volume 74 Issue 3 Pages 184-188
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.3_184
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    This paper describes a fundamental study on the conversion of ammonium sulfate to ammonia solution using bipolar-membrane electrodialysis. The electrodialyzer was composed of two electrode compartments and three compartments/unit, which were divided by three anion-exchange membranes and a bipolar membrane. The solutions including ammonium sulfate were circulated by chemical pumps through the compartments and reservoirs. When a voltage was supplied to the electrodialyzer, hydroxide ions were generated by the bipolar membrane, and partially moved to the anode side compartments through anion-exchange membranes, then sulfate ions were substituted with hydroxide ions. The concentration of generated ammonia solution was affected by the ammonium sulfate concentration in the raw solution. The solution pHs including ammonium hydroxide were explained using calculated values that considered the material balance of ammonium, dissociation of ammonia and water, and electroneutrality of ions in the solution.
    View full abstract
    Download PDF (1368K)
Short Paper
  • Fouling Properties of Anion-exchange Membranes with a Negatively-charged Layer Prepared from PVA-based Block Copolymers
    Saeko HARADA, Yuriko KAKIHANA, Mitsuru HIGA
    2020 Volume 74 Issue 3 Pages 189-190
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.3_189
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    In this study, we investigated the fouling properties of poly（vinyl alcohol）（PVA）-based anion-exchange membranes（AEMs） with a negatively-charged layer on the membrane surface by an electrodialysis test using a mixed NaCl and sodium linear-alkyl benzenesulfonate solution. In the ED test, the slope in the voltage drop-time curve of the prepared AEM with coating of 2 wt.％ polyanion solution was about 1/50 of that of a commercial standard AEM, NEOSEPTA® AMX（ASTOM corp.）, indicating that the hydrophilic matrix and the negatively-charged layer of the prepared AEM shows higher anti-fouling properties than AMX, and the anti-fouling properties of the AEMs increase with increasing coating solution concentration of the negatively-charged layer. These results indicate that our modification method can be used in the preparation of AEMs with high anti-organic-fouling properties.
    View full abstract
    Download PDF (625K)
  • Increase in the Density of Cypris Larvae Settlement in a Higher Emission Area of Bioluminescence from Photobacterium leiognathi Suspended in a Test Tube
    Masao KITAMURA, Haruo MIMURA, Nobumichi SHUTOH, Hiroki HOTTA
    2020 Volume 74 Issue 3 Pages 191-192
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.3_191
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    The settlement of cypris larvae was examined in a dark room when the emission of blue to blue-green bioluminescence from Photobacterium leiognathi cells existing in seawater was suspended in a test tube. The number of cypris larvae that settled on the test tube increased as compared with that on the test tube without P. leiognathi cells. The density of settlement was analyzed statistically in relation to the distance from the surface of the seawater in a container. The result showed that cypris larvae settled preferentially in the area of higher luminescence located at the surface of the cell suspension.
    View full abstract
    Download PDF (755K)
Kaisui-seikatsu-kagakurenkei symposium: Reflections to move forward
Lecture
Relay Essay (43)
Introduction of Research Committees
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top