Zairyo-to-Kankyo
New Arrival Alert : OFF

You can use this feature after you logged into the site.
Please click the button below.

Log in / Sign up
ONLINE ISSN: 1881-9664
PRINT ISSN: 0917-0480

Zairyo-to-Kankyo Vol. 58 (2009), No. 3

  • Open Your Eyes –Corrosion versus Medichine–

    pp. 81-81

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.3323/jcorr.58.81

  • Life Cycle Management of Port Structures – IV

    pp. 82-85

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.3323/jcorr.58.82

    Based on the PIANC PTC-II WG31 report1), the LCM of port structures has been introduced in Japan2)-6). Especially, the two repair options with equal lives at the Kamsar Port are economically compared using the Present Worth (PW) method. In present worth analysis, the PW is calculated at the Minimum Attractive Rate of Return (MARR), which is an inflation-free interest rate. When inflation occurs, the effect of inflation on the PW method must be examined.
    Since a present worth comparison involves calculating the equivalent present value of all future cash flows for each option, the PW of the options must be compared over the same number of years and end at the same time. The PW comparison of options with equal lives is straightforward. When options being compared have different lives, the Annual Worth (AW) method of comparing options is often preferred to the PW method, because AW comparison is performed for only one life cycle.
    In this report, the effect of inflation on the PW method is considered using the data of the Kamsar Port in the WG31 report, and the application of the PW and AW methods to unequal-life options is shown.
  • Effects of Bubble Behavior on Erosion Corrosion of Copper Tubes in Hot-Water Supply System

    pp. 99-104

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.3323/jcorr.58.99

    The survey results of recent 120 leakage accidents showed that most of erosion corrosion failures of copper tubes in hot-water forced circulation system have been experienced at the downstream of joints of the return tubes. This tendency was the same as that of the research in 1996. The erosion corrosion of copper tube was observed when the concentration of dissolved oxygen in the hot-supply water was supersaturated and higher than that in supplied tap water. Therefore, it was presumed that erosion corrosion of copper tube was caused by the bubbles formed by pressure change in hot-water forced circulation system. The results of Computational fluid dynamics (CFD) simulations and the observation of the flow pattern in the model plumbing equipment showed that the locus of the micro-bubbles affect of the erosion corrosion of copper tube. According to the Young-Laplace equation, more small bubbles have high pressure in inside of the bubble, and maintain as the bubble without coalesce or collapse of bubbles. Consequently, it could be considered that erosion corrosion of copper tube occurred and propagated when the protective films formed on the tubes surfaces were continuously broken by micro-bubbles.
  • Corrosion Behavior of AZ31 Magnesium Alloy in Dilute Sodium Chloride Solutions

    pp. 105-110

    Bookmark

    You can use this feature after you logged into the site.
    Please click the button below.

    Log in / Sign Up

    DOI:10.3323/jcorr.58.105

    Corrosion behavior of AZ31 magnesium alloy in dilute NaCl solutions was studied by electrochemical techniques. Its surface film was chemically characterized by X-ray diffraction (XRD). A corrosion map in terms of electrode potential and chloride concentration [Cl] was obtained by using electrochemical measurements. With the map, passivation and corrosion zones were determined. The passivation zone was found to become narrow with the increasing of [Cl] . The values of Eocp, open-circuit potential, in nondeaerated NaCl solutions were in the passivation zone when [Cl] <0.2 M and in the corrosion zone when [Cl] ≥0.2 M. The reduction reactions of dissolved oxygen and hydrogen evolution worked as cathodic reactions in nondeaerated solutions. By XRD analyses, Mg(OH)2, magnesium hydroxyl carbonate, and MgO were the dominant products in the corrosion zone, whereas magnesium hydroxyl carbonate and MgO were the main components in the passivated film.

Article Access Ranking

30 Sep. (Last 30 Days)

  1. Deformation of Non-metallic Inclusions in Steel during Rolling Process: A Review ISIJ International Advance Publication
  2. Interaction Coefficients of Cu and Sn with Mn in Molten Iron at 1873 K ISIJ International Advance Publication
  3. Thickness classifier on steel in heavy melting scrap by deep-learning-based image analysis ISIJ International Advance Publication
  4. Bandwidth Maximization of Disturbance Observer Based on Experimental Frequency Response Data SICE Journal of Control, Measurement, and System Integration Vol.13(2020), No.6
  5. Soft sensors and Diagnostic Models Using Real Time Data of Blast Furnaces at Tata Steel ISIJ International Advance Publication
  6. Effect of SiO2 content and mass ratio of CaO to Al2O3 on the viscosity and structure of CaO-Al2O3-B2O3-SiO2 slags ISIJ International Advance Publication
  7. Thermodynamic Conditions of MgO and MgO·Al2O3 Formation and Variation of Inclusions Formed in Fe-17 mass%Cr Steel at 1873 K Tetsu-to-Hagané Vol.108(2022), No.8
  8. Non-Cooperative Optimization Algorithm of Charging Scheduling for Electric Vehicle SICE Journal of Control, Measurement, and System Integration Vol.13(2020), No.6
  9. Comparison of Oxidation Behavior of Various Reactive Elements in Alloys during Electroslag Remelting (ESR) Process: An Overview ISIJ International Vol.62(2022), No.8
  10. Effect of 2CaO·SiO2 Addition on Reaction Behavior of Iron Ore Sinters ISIJ International Vol.62(2022), No.9

Search Phrase Ranking

30 Sep. (Last 30 Days)

  1. blast furnace
  2. 鉄と鋼
  3. si-killed spring steel
  4. hydrogen trapping
  5. isij international
  6. steel
  7. bake hardening
  8. damping alloy
  9. matsumura
  10. pickling