• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.3
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• pp.113-116
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• 2007

We investigated the characteristics of various Tofu coagulants extracted from sea tangle using treated deep ocean water (DOW) as the solvents. The coagulants were typical solutions extracted from sea tangle using raw DOW and strongly electrolyzed acidic (SAC) or alkaline (SAK) water. The total dissolved solids (TDS), NaCl and electric conductivity were increased in the coagulant solution extracted by SAC than the others. In the coagulant solutions extracted by acidic electrolyzed solvent, aspartic acid content (13.5 mg/100 g) was higher than others (11.2 and 12.1 mg/100 g). The Tofu obtained using coagulants extracted with treated DOW had the water contents ranging from 79.55% to 80.04%. The contents of crude protein (12.1 g/100 g) and Na, Ca, K and Mg were relatively higher than general Tofu commercially available. Therefore, coagulant solutions extracted from sea tangle using treated DOW can be used to develop natural high-grade tofu for practical use.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.11
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• pp.3433-3440
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• 1996

This paper was investigation of the stres corrosion cracking(SCC) mechanism and the properties of corrosion fracture surface of glass fiber reinforced plastics(GFRP) produced by hand lay up(HLU) method in synthetic sea water. Test material is GFRP, that was used vinylester type epoxy acrylate resin and an unsaturated polyester as the matrix and the chopped strand mat(CSM) type E-glss fiber as the reinforcement. The slow strain rate test(SSRT) was performed on dry, wet and saturated wet specimens in sea water. Here the pH concentration of synthetic sea water was 8.2 and the strain rate is 1 x $10^{-6}$($sec^{-1}$) and test temperature ranges varied from $-60^{\circ}C$ to $80^{\circ}C$. It could be confirmed the fact that wet specimens tested at a particular test temperature ranges were appeared the eviences of SCC such as con-planar, mirror and hackle zone. Moreover, SCC of GFRP in sea water was characterised by falt fracture surfaces with only small amounts of fiber pull-out, in partial.

• Journal of Ocean Engineering and Technology
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• v.29 no.4
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• pp.300-308
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• 2015

With the increases in oil and gas prices, and energy consumption, drillship construction has increased during the last decade. A drillship using a dynamic positioning (DP) system to maintain its position and heading angle during drilling operations. In addition, a drillship is equipped with a moonpool structure to allow its drilling systems to be operated in the midship section. A drillship for the North Sea is specially designed to endure harsh environmental loads. For safe operation in the North Sea, the drillship should have good motion response and robust hull strength. A break water should be considered on the bow and side deck to prevent the green water on deck phenomenon from incoming waves. In addition, the moonpool should be designed to reduce the speed loss and resonance motion. In this study, the hydrodynamic characteristics of a drillship for the North Sea were examined in relation to the motion, wave loads, green water, and moonpool resonance in the initial design stage.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1279-1284
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• 2008

The alternative energy has lately attracted considerable attention due to the high oil price and environment problem. Deep sea water that is one of the natural energy sources should be getting popular continually to reduce the environment problem. In this study, cooling system of deep sea water using heat exchangers of two hotels where is located in near Hae-undae Bay has been analyzed on the quantity of electricity comparison between existing cooling system and deep seawater cooling system. As shortly, the results of study showed that the first building approximately saves 370 millions won per year, also the second building saves 248 millions won per year. It means that the cooling system by using deep sea water has great worth to reduce the ratio of fossil fuel.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.2
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• pp.149-154
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• 2010

The feasibility of lead removal by electrolytic coprecipitation was investigated. Electrolysis bath was divided into anode and cathode chamber with anion exchange resin filled membrane. Sea water was electrolyzed and pH of the electrolyte in cathode chamber was increased. Consequently it induced the formation of $Mg(OH)_2$ and $CaCO_3$. The colloidal type precipitates, hich have high surface area, adsorbed lead ions in sea water and coprecipitated. Sea water electrolyses were conducted at different current density. Concentrations of Mg, Ca and Pb in the solution were measured with titration and ASV method. Morphology and crystallography were analyzed with SEM, EDS and XRD. As pH and current density increased, most of lead ions in the sea water were successfully removed.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.855-859
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• 2000

An application of synergistic solvent extraction for the etermination of trace lithium in sea water has been studied by forming an adduct complex of thenoyltrifluoroacetone (TTA) and trioctylphosphine oxide (TOPO) in a solvent. The interference by major constituents in sea water was eliminated by phosphate precipitation. Ex-perimental conditions such as solution pH, concentrations of TTA and TOPO etc. were optimized in synthetic sea water with similar compositionto its natural counterpart. To eliminate the interference, 1.38g of ammoni-um dihydrogen phosphate and 2.5 mL of ammonia water were added into 100 mL of thediluted solution at $60^{\circ}C$ to form the phosphate precipitates of Ca2+ and Mg2+ ions. After the pH of this filtrate was adjusted to 8.0, 10.0 mL of m-xylene containing 0.1 M TTA and 0.05 M TOPO was added to the solution in a separatory funnel, and the solution was shaken vigorously for 20 minutes. The solvent was separated from the aqueous solution, and 20 uL of m-xylene solution was injected into a gaphite tube to measure the absorbance by GF-AAS. The detection limit was 0.42 ng/mL. Lithium was determined within the range of 146 to 221 ng/mLin Korean coast-al sea waters, and the recoveries in the spiked samples were 94 to 106%.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.142-142
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• 2018

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.1169-1174
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• 2001

In this study, the behavior of deteriorated concrete columns under sea-water before and after strengthening with glass fiber composite and the change of behavior by the deterioration of strengthening material are analyzed. In the analysis, the characteristics of concrete deteriorated in sea-water, preloading effect, and corrosion of steel are considered. The result of analysis is verified by the comparison with the experimental data. Using constitutive equations of the concrete and corroded steel, load-moment interaction curves of both deteriorated and strengthened concrete column are derived.

• 한국해양학회지
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• v.5 no.1
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• pp.1-5
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• 1970

The hydration numbers of some salts present in sea water have been calculated by a simple model for the equation of the dielectric constant, and the mean activity coefficients from the theoretical formula proposed by Jhon and Eyring. The validity of the theory for the electrolyte solution is tested by evaluating the hydration numbers and the mean activity coefficients of some 1:1, 1:2, 2:1 and 1:3 electrolytes in sea water. The results show good agreement with the observations.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.3
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• pp.463-473
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• 2017

Bentonite swells when it comes into contact with water and makes it a viscous fluid. Thus it is widely used in civil engineering works for waterproofing. Utilizing the properties of bentonite, the slurry shield TBM supports excavated face with pressurized slurry as well as transporting excavated muck. When bentonite is in contact with seawater, due to the change of double layer thickness, its expandability and viscosity are lowered. This may cause problems for excavation stability and muck discharge due to the increase of sea water inflow when Slurry TBM is used under sea water conditions. In this study, the change of slurry condition caused by the inflow of sea water during tunnel excavation with Slurry TBM was investigated and a slurry management guideline was proposed. For this purpose, a laboratory test was carried out based on the slurry management criterions applied in the field, and a method applicable to the field where sea water is affected has been proposed.