• Corrosion Science and Technology
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• v.10 no.6
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• pp.205-211
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• 2011

The severe corrosion environment makes the steel product lifecycle short while Cu-alloys with anti-corrosion characteristic used in sea water are too expensive. This study shows that the Cu-alloy(Cu-37.25% Zn-0.67%Al) used in sea water environment can be superseded by SS400 with various coating process, evaluating electrochemical characteristics. Three coating processes were applied to SS400 such as PTFE + Zn coaing, Zn + PTFE coating and only Zn electrogalvanizing coaing. Various electrochemical experiments such as open circuit potential measurments, potentiodynamic polarization tests and analyses of Tafel constants. Mechanical properties were also measured by tensile test and hardness tests. As a result, Zn + PTFE coating for SS400 steel presented the excellent anti-corrosion characteristic in sea water.

• Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.22.1-22.7
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• 2016

One of the main compounds in Ishige okamurae, diphlorethohydroxycarmalol (DPHC), is known to exhibit antiviral and anti-inflammatory effects. However, it has not been investigated extensively. In this study, preparative centrifugal partition chromatography (CPC) coupled with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) ($ABTS^+$) online HPLC was employed for effectively separating considerable amounts of antioxidant compounds from marine algae. Two main antioxidant compounds, DPHC and octaphlorethol A (OPA), respectively, were confirmed and isolated from the ethyl acetate (EtOAc) fraction of I. okamurae by $ABTS^+$ online HPLC and preparative CPC systems. The presence of DPHC and OPA was confirmed in the EtOAc fraction of I. okamurae by both liquid chromatography with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI/MS) and $ABTS^+$ online HPLC systems: DPHC (39 mg) and OPA (23 mg) were successfully isolated from I. okamurae (500 mg) with optimum solvent composition (0.5:10:4:6; n-hexane/EtOAc/MeOH/water, v/v) with corresponding partition coefficients (K) of 1.62 and 2.71, respectively, by preparative CPC. Hence, CPC coupled with $ABTS^+$ online HPLC is convenient for the efficient and simple isolation of these antioxidant compounds from I. okamurae.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.129-130
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• 2014

In the case of concrete structures which have been recently exposed to the marine environment, durability is greatly reduced by the freezing-thawing action. When it is used by appropriately replacing the ground granulated blast-furnace slag(GGBS) that is a industrial by-product, the concrete structure of marine environment is known to have a durability to freezing-thawing resistance. In this experiment, micropore in accordance with a replacement ratio of GGBS was confirmed to show different results respectively. The freeze-thaw resistance was showed different aspects respectively because it is different the amount of water in the pore due to the difference of micropore. Therefore, in this study, the freezing-thawing resistance of sea water by variation of micropores of slag concrete had been evaluated.

• The Journal of Fisheries Business Administration
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• v.28 no.2
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• pp.39-66
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• 1997

The objective of this study is to suggest the improvement method of the profitability in our marine fish culture business. So I investigated the actual condition for aquaculture farms in South Sea coast by the question and actual survey. 1 recognized the following facts; 1) The marine floating netcage system are a great portion in two province - Kyeongnam and Cheunnam, 2) The rockfish are reared absolutely much more than the olive flounder, 3) The polyculture by various species are more carried out than the monoculture of the olive flounder or rockfish, etc. I analyzed the profitability in olive flounder monoculture, rockfish monoculture, olive flounder and rockfish polyculture, and rockfish polyculture taking turns year by year respectively. At a result I comfirmed that the net income to net sales was the highest in the olive flounder monoculture bacouse the olive flounder,s sale price was higher than rockfish price. But internal rate of return(IRR) and net present value(NPV) were high in the olive flounder and rockfish polyculture or the rockfish taking turns polyculture. The reasons were alttributed to their high utility of a netcage and to reduction of a capital cost. So, I suggest 1) to feed the bigger product in short term, 2) to reduction of a feed and seed cost, 3) to increase a survival rate of fish and 4) to enlarge production by highly utilizing a netcage. And I recognized that a aquaculture manager should make constantly an effort to gain more profit by rearing more good products and by reducing a production cost.

• YAKHAK HOEJI
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• v.40 no.5
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• pp.574-581
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• 1996

The study was initiated to elucidate the protective mechanism by examining in vivo effect of some marine natural products, Styela plicata, Ecklonia stolonifera and Pachymeniopsis elliptica on acetaminophen-induced lipid peroxidation. The methanol extract of S. plicata prevented acetaminophen (800mg/kg, i.p.)-induced hepatotoxicity in rats as evidenced by the decreased formation of lipid peroxide. But the methanol extracts of E. stolonifera and P. elliptica were not affected on the formation of lipid peroxidation. The activities of cytochrome P-450, animopyrine N-demethylase and aniline hydroxylase were not changed by the treatment with S. plicata in comparison with acetaminophen-teated group. In acetaminophen-treated control rats, the glutathione S-transferase activity was decreased markably. However. in S. plicata pretreated group, the effect caused by acetaminophen was markably reduced. A-cetaminophen decreased the level of hepatic, glutathione, which was restored to same degree by S. plicata pretreatment. And activity of ${\gamma}$-glutamylcystein synthetase was not changed by S. plicata pretreatment, but the activity of glutathione reductase was increased significantly.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.10-15
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• 2010

This study was practiced to survey food-borne bacterial aspects of Escherichia coli and Bacilhus cereus etc. from 210 processed seasoned marine products in Garak fishery wholesale market in Seoul, 2009. Distributions of these bacterial isolates were 28 coliforms, 32 Bacillus spp., 71 Staphylococcus spp., 11 Listeria spp, and 10 Enterococcus spp. in 157 dried squids, 23 dried file fishes, and 20 dried pollacks etc. respectively. Results in 16 kinds of antibiotics susceptibility test by disc diffusion method, special multiple drugs resistance patterns were NOR + LVX + CIP + SAM + VA + S + TE + CF, SAM + C + VA, VA + S + TE, and VA + S in 9 E. coli strains, also, AMC + SAM + CF, SAM + CF, and VA + CF in 21 Bacillus cereus strains respectively. On the basis of the results above, many seasoned dried fishes had multiple drugs resistances, conclusively, we suggest limited guideline and special management on use of antibiotics in floating net cages of fishery farms.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.4
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• pp.257-262
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• 2007

Squid viscera oil was investigated by pretreatment method for enhancing the commercial value. Transeterification was performed to reduce rancidity of the oil, off-flavor was removed by using activated carbon adsorption. Analysis using ATD (Automatic Thermal Desorber) and GC/MG shows the efficacy of off-flavor removement. The rates of Transesterification employing inorganic catalyst and biocatalyst were tested, respectively. With stepwise addition of ethanol, the most efficiency of the reaction was achieved by inorganic catalyst. The efficiency of the reaction was estimated by acid value corresponding to rancidity of reaction product.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.36
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• pp.143-170
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• 2007

In order to analyze the distribution channel of marine products in Korea, this study shows SCM approach to redesign of the marine distribution channel with case study related to previous literatures. In view of the supply chain and the future impact of RFID on the marine SCM on the recognition of the importance of the seafood traceability system, this study also provides the possibility to accomplish effective SCM for integration of production, storage, transportation, delivery, and sale when RFID is used in the seafood distribution channel based on the expansion of awareness on the marine product traceability. The traceability system for seafood is considered as the distribution infrastructure established in RFID deployment. By introducing Lotte mart case, this case study also discusses the marine distribution structure in view of the supply chain, to present an effective foundation for supplying seafood throughout production, distribution, and consumption. This is achieved by introducing RFID in an ubiquitous environment, and suggesting far more efficient control planning throughout the seafood distribution channel in view of the expected effects resulting from the introduction. In addition, as the alternative of solving this situation, this study propose the supply chain in seafoods by comprehensive management in whole distribution channels. In the SCM in seafood perspectives, HACCP can take into account the whole seafood chain from the point of supply to the point of consumption when assessing hazards. As the contributions of this study, this study emphasizes the seafood industry first should require the establishment of the relevant infrastructure, for which the efforts of the government and demonstrative project participants are essential.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.454-458
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• 2015

This study compared the effects of dietary supplementation of citrus by-product (CBP) and CBP fermented with Bacillus subtilis (F-CBP) on growth performance, feed utilization, intestinal histology and innate immunity of red seabream Pagrus major with three commercial immune-boosting products. The six experimental diets were supplemented with L-ascorbyl-2-polyphosphate (LAPP; the control diet), CBP or F-CBP at a concentration of 100 mg vitamin C equivalent/kg diet or one of three commercial immune boosters. The Experimental diets were fed to triplicate groups of 17 fish (initial body weight, 116 g) for 8 weeks. The water temperature during the feeding trial was maintained at $13-15^{\circ}C$. Growth and feed utilization did not differ significantly among the six dietary treatments, nor did the phagocytic activity, superoxide dismutase or total immunoglobulin concentrations. However, myeloperoxidase activity was significantly higher in the CBP groups. For the intestinal histology, the intestine diameter, villi and enterocyte heights and number of goblet cells did not differ significantly among groups. Therefore, CBP or F-CBP can be used as a valuable eco-friendly byproduct in diets for fishes including red seabream to maintain their normal growth and health.

• Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.279-283
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• 2013

We tested the effects of various distillers dried grains (DDGs) in a formulated diet on growth and body composition of juvenile sea cucumber Apostichopus japonicus. DDG is a solid residue obtained by filtering an aqueous mixture of fermented rice with Aspergillus oryzae and yeasts. Six isonitrogenous and isocaloric diets (DDG0, DDG-G, DDG-C, DDG-K, DDG-W, and DDG-P) were formulated to contain 20% DDG obtained from different Makgeolli factories. Juvenile sea cucumber (average weight, $2.1{\pm}0.02$ g) were randomly distributed in eighteen 50-L rectangular plastic tanks (40 L of water each) in a seawater flow-through system at a density of 50 juveniles/tank. Three replicate groups of sea cucumber were fed each of the six experimental diets at a feeding rate of 5% body weight per day for 22 weeks. At the end of the feeding experiment, survival and weight gain of the juvenile sea cucumber were not affected by the type of dietary DDG (P > 0.05), and the proximate and amino acid compositions of the whole body were not affected by dietary DDG diets (P > 0.05). These results indicate that rice-based DDG is a potential dietary ingredient that could be used at dietary concentrations of up to 20% for growth of juvenile sea cucumber.