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 1
Displaying 1-11 of 11 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
Preface
Special Issue : “A Study of the Seawater of West Japan (9)”
Commentary
Original Paper
  • Improvement of Insulin Resistance in Fish Muscle by Oral Administration of Natural Bio-materials
    Kiyomi TAKASE, Izuru KAKUTA
    2020 Volume 74 Issue 1 Pages 27-35
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.1_27
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    Most fish are characterized by a limited efficiency to use carbohydrates, however, the exact mechanism of glucose intolerance in teleost fish is still unclear. The purpose of this study was to determine the effects of many different kinds of natural bio-materials on insulin resistance in fish white muscle. Sixteen bio-materials were administered orally at the amount of 100 mg/kg BW/day except lactoferrin （LF ; 200 mg/kg BW/day） to goldfish （Carassius auratus） for 3 weeks, and the ability to improve insulin sensitivity was examined individually. On week 3, the rate of 2-deoxy-D-glucose （2DG） uptake in the white muscle was measured. The rate in the goldfish muscle was less than one-sixth of those in mammals such as mice and rats, that is, an extremely high insulin resistance in fish muscle was found. Oral administration of a wild plant mineral mixture, seaweed mineral mixture, red ginseng and inositol improved markedly the insulin sensitivity in trunk muscle of fish. These findings suggest that the administration of these bio-materials induces a greater potential to utilize dietary carbohydrates as an energy source to spare protein. Consequently, the costs to aquaculture diets may be substantially reduced and moreover may lead to a solution of the global protein supply shortage.
    View full abstract
    Download PDF (910K)
  • Controlling Production Regions of Ca and Mg Carbonates Obtained by CO2 Fine Bubble Injection into Concentrated Brine
    Masakazu MATSUMOTO, Yoshinari WADA, Yukikazu TAKASHIMA, Taichi KIMURA, ...
    2020 Volume 74 Issue 1 Pages 36-43
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.1_36
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    To develop a utilization system for seawater resources based on the salt production process, a method for recovery and upgrading of Ca and Mg from the concentrated brine discharge of a salt manufacturer in Japan was examined. From a salt solubility viewpoint, the synthesis of the carbonates by reactive crystallization between the dissolved Ca2＋ and Mg2＋ ions in concentrated brine and CO2 can be considered as an effective separation/recovery method. In this study, the production regions of the Ca and Mg carbonates were classified according to the solution pH and temperature （TS） during reactive crystallization from concentrated brine, using the gas–liquid interfaces surrounding the CO2 fine bubbles. In the regions near the minute gas–liquid interfaces, the local increase in the Ca2＋, Mg2＋, and CO32－ concentrations was caused by the electric charge on the fine bubble surface and the acceleration of CO2 mass transfer as a result of a reduction in the bubble diameter. Additionally, at high solution pH and TS values of the concentrated brine, the production of Ca and Mg carbonates could be controlled because of the variation in the local supersaturation, i.e., the concentration difference between the gas–liquid interfaces and bulk solution. This was attained by changing the local concentrations of the Ca2＋, Mg2＋, and CO32－ ions at the gas–liquid interfaces and the Ca and Mg carbonate solubilities in the bulk solution. At the pH range 5.3–8.3 and TS range 278–348 K, CO2 fine bubbles with an average diameter of 40 μm were continuously supplied to concentrated brine derived from salt manufacture discharge. The Ca and Mg carbonates crystallized within a reaction time of 60 min. Consequently, CaMg（CO3）2 was crystallized at the pH range 5.3–6.8 and TS range 278–298 K with high selectivity. Aragonite form CaCO3 was preferentially produced at TS ＞333 K and the pH values 5.3 and 6.0. At solution pH values ＞7.8 and constant TS 298 K, Mg（OH）2 was precipitated as a by-product together with CaMg（CO3）2 and aragonite form CaCO3.
    View full abstract
    Download PDF (1384K)
  • Numerical Analysis for Crystal Growth and Local Supersaturation on the Crystal Trajectory in Anti-solvent Crystallization with Y-shaped Channel
    Jun TERADA, Ryuta MISUMI, Meguru KAMINOYAMA, Kazuhiko NISHI
    2020 Volume 74 Issue 1 Pages 44-49
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.1_44
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    This study examines a method for elucidating the relation between the size distribution of crystals and the local supersaturation distribution obtained from simulation. To apply simulation results to equipment design and process control, one must understand relations prevailing among the distribution of physical quantities, nucleation, and crystal growth. Simulation results obtained for KCl–ethanol anti-solvent crystallization in a Y-shaped channel are used as an example. The trajectory on which crystals move in the channel is specifically examined. The concentrations of the solute and of the anti-solvent on the trajectory are drawn on a ternary phase diagram. The crystal size distribution is indicated as explainable quantitatively from the solute and the anti-solvent concentration and local supersaturation change on the trajectory which are drawn on the ternary phase diagram. Appropriate equipment design and process control conditions might be obtainable from the supersaturation changes on the crystal trajectory obtained using this method.
    View full abstract
    Download PDF (1746K)
Short Paper
  • Monovalent Selective Anion-exchange Membranes Prepared from PVA-based Block Copolymers
    Saeko HARADA, Yuriko KAKIHANA, Mitsuru HIGA
    2020 Volume 74 Issue 1 Pages 50-51
    Published: 2020
    Released on J-STAGE: October 01, 2021
    DOIhttps://doi.org/10.11457/swsj.74.1_50
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    In this study, we prepared novel PVA-based anion-exchange membranes with monovalent anion permselectivity by coating one of the membrane surfaces with an aqueous solution of PVA-based block copolymers. To determine the permselectivity between Cl－ ions and SO42－ ions through the membrane, electrodialysis was carried out using a mixed NaCl and Na2SO4 solution. The permselectivity for Cl－ ions against SO42－ ions through the membrane increased with increasing coating solution concentration while membrane resistance was almost independent of the coating solution concentration. Also, a coating layer having a higher amount of charge group showed higher permselectivity. These results indicate that our modification method can be used to prepare a membrane with high permselectivity for monovalent anions without changing its membrane resistance.
    View full abstract
    Download PDF (564K)
Lecture
Relay Essay (41)
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top