• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.3
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• pp.143-156
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• 2015

In order to understand the dynamic characteristics of water column environments in the Western Pacific seamount area (approximately $150.2^{\circ}E$, $20^{\circ}N$), we investigated the water mass and the behavior of water column parameters such as dissolved oxygen, inorganic nutrients (N, P), and chlorophyll-a. Physico-chemical properties of water column were obtained by CTD system at the nine stations which were selected along the east-west and south-north direction around the seamount (OSM14-2) in October 2014. From the temperature-salinity diagram, the main water masses were separated into North Pacific Tropical Water and Thermocline Water in the surface layer, North Pacific Intermediate Water in the intermediate layer, and North Pacific Deep Water in the bottom layer, respectively. Oxygen minimum zone (OMZ, mean $O_2$ $73.26{\mu}M$), known as dysoxic condition ($O_2<90{\mu}M$), was distributed in the depth range of 700~1,200 m throughout the study area. Inorganic nutrients typified by nitrite + nitrate and phosphate showed the lowest concentration in the surface mixed layer and then gradually increased downward with representing the maximum concentration in the OMZ, with lower N:P ratio (13.7), indicating that the nitrogen is regarded as limiting factor for primary production. Vertical distribution of water column parameters along the east-west and south-north station line around the seamount showed the effect of bottom water inflowing at around 500 m deep in the western and southern region, and concentrations of water column parameters in the bottom layer (below 2,500 m deep) of the western and southern region were differently distributed comparing to those of the other side regions (eastern and northern). The value of Excess N calculated from Redfield ratio (N:P=16:1) represented the negative value throughout the study area, which indicated the nitrogen sink dominant environments, and relative higher value of Excess N observed in the bottom layer of western and southern region. These observations suggest that the topographic features of a seamount influence the circulation of bottom current and its effects play a significant role in determining the behavior of water column environmental parameters.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1364-1368
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• 2015

This study was performed to evaluate mineral contents of catfish Silurus asotus. As a result of mineral content, the mean content of the macro mineral was (in descending order): K (310.36-412.66 mg/100 g), P (186.42-223.02 mg/100 g), Na (35.32-57.87 mg/100 g), Mg (22.88-31.87 mg/100 g), Ca (9.05-13.07 mg/100 g). In comparison, the mean content of the micro mineral was (in descending order): Fe (0.26-0.95 mg/100 g), Zn (0.26-1.02 mg/100 g), Cu (ND-0.08 mg/100 g), Mn (0.01-0.03 mg/100 g). A proportion of mineral intakes with the dietary reference intakes for Koreans (KDRIs) set by the Korean Nutrition Society. Nutrient uptake proportion of mineral intakes was (in descending order): P (62.16%), K (20.71%), Mg (16.82%), Fe (13.02%), Zn (11.38%) Cu (10.94%), Na (6.59%), Ca (3.09%), Mn (0.96%). The mineral content was compared with the major protein food sources according to the Korea Health Statistics (2013) such as polished rice, pork, chicken, beef, eggs and milk. The calcium content contains; lower level of milk and eggs, chicken whereas higher levels of rice, pork and beef. Catfish has less iron content than major protein food source. Phosphorus and potassium contain higher level of major protein food sources.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.6
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• pp.393-398
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• 2008

Several researchers have proposed models or equations to predict soil $CO_2$ flux from more readily available biotic and abiotic measurement. Tree commonly used abiotic variables were N mineral and soil temperature and soil water content. This study was conducted to determine $CO_2$ emission to mineral N, soil water content and soil temperature with clay loam and sandy loam in pepper cultivation in 2004~2005. $CO_2$ flux in the upland with different levels of soil water potential was measured at least once in two weeks during the cropping period in the pepper cultivation plots. Soil water potential in the clay loam and sandy loam soils was established at -30kPa and -50kPa by measuring the soil gravimetric water content with two replications. $CO_2$ emission rate from the differently managed plots was highly correlation coefficient to between the mineral N ($R=0.830^{**}$, $0.876^{**}$) and soil temperature ($r^2=0.793^{**}$, $0.804^{**}$) in the clay loam and sandy loam, respectively. However, the relationships between $CO_2$ emission and soil water content were non-significant. $CO_2$ emissions at sandy loam soils was lower to 21~37% than at clay loam soils for both soil water conditions without differences in yield. At difference levels of soil water conditions, $CO_2$ emission at -50kPa decreased to 37.5% in comparison with that at -30kPa. From the path analysis as to contribution factors of GHGs, it appeared that contribution rate was in the order of soil temperature (54.9%), mineral N (32.7%), and soil moisture content (12.4%).

• Applied Biological Chemistry
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• v.36 no.4
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• pp.249-254
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• 1993

The dried cinnamon was extracted with water and 70% ethanol and studied for the several extraction conditions of temperature, time, solvent addition ratio and number of extraction on mineral components and physical properties of the extracts. Mineral components significantly increased as the extraction temperature increased. More than 8 hours of extraction showed a little improving while solvent ratio (V/W) up to 60 times (V/W) significantly increased the mineral components, particularly Cu, Zn, Fe, Na in water extracts and Fe, Mn, K in 70% ethanol extracts. Absorbance at 285 mm decreased as the temperature raised up to the range of $60{\sim}80^{\circ}C$. The Hunter a-value was much affected with extraction conditions and L-value and transmittance were changed similarily while pH was little changed.

• Journal of Soil and Groundwater Environment
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• v.16 no.2
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• pp.41-51
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• 2011

This study was conducted to investigate the relationship between groundwater level change and a large earthquake using the data of groundwater and seawater intrusion monitoring wells in Jeju Island. Groundwater level data from 13 observation wells were analyzed with a large earthquake. The Earthquake occurred at Sumatra, Indonesia (Mw = 7.7) on 13 June 2010, and groundwater level anomalies which seems to be related to the Earthquake were found in 6 monitoring wells. They lasted for approximately 16~27 minutes and the range of groundwater level fluctuations were about 1.4~2.4 cm. Coefficient of determination values for relationship between groundwater level change and transmissivity, and response time were calculated to be $R^2$ = 0.76 and $R^2$ = 0.96, respectively. The study also indicates that the high transmissivity of aquifer showed the high goundwater level changes and longer response time.

• Korean Journal of Community Nutrition
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• v.24 no.1
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• pp.18-23
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• 2019

Objectives: Although water is essential for life and can supply essential minerals, studies that evaluate calcium intake through drinking water are limited. The aim of this study was to assess calcium contents of natural mineral water (NMW) and its possible contribution to calcium intake in healthy adults. Methods: This study examined water consumption in 640 Korean adults with self-selected diet, analyzed the calcium content of 10 different brands of bottled NMWs sold in Korea, and assessed the amount of calcium intake from drinking water and its daily contribution to the recommended nutrient intake (RNI) of calcium. Results: Mean calcium content in 10 bottled NMWs was 20.9 mg/l. Daily water intakes from food composition database and calculated using energy intake based on 0.53 ml/kcal were 957.2 ml and 1109.8 ml for men and 848.3 ml and 951.6 ml for women, respectively, with a significant difference by gender (p<0.001). Daily drinking water intake was significantly higher among men than women (1203.9 ml vs. 1004.3 ml, respectively, p<0.001). Daily calcium intakes from foods were 564.0 mg for men and 534.2 mg for women. Daily possible calcium intakes from drinking bottled water were 25.2 mg for men and 21.0 mg for women (p<0.001). The contribution of daily calcium intake from drinking bottled water to RNI of calcium was 3.3% for men and 2.9% for women without significant difference. Conclusions: One half of the daily total water intake was consumed as drinking water, and possible calcium intake through drinking water was about 3% of RNI.

• Journal of the Korean Chemical Society
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• v.44 no.4
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• pp.380-386
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• 2000

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.1
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• pp.18-24
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• 2016

Mineral carbonation is a technology for permanently storing carbon dioxide by reacting with metal oxides containing calcium and magnesium. In this study, we used sea water and alkaline industrial by-product such as paper sludge ash (PSA) for the storage of carbon dioxide through direct carbonation. We found the optimum conditions of both sea water content (mixing ratio of sea water and PSA) and reaction time required in the direct carbonation through various experiments using sea water and PSA. In addition, we compared the amounts of carbon dioxide storage with the cases when sea water and ultra-pure water were separately used as solvents in the direct carbonation with PSA. The amount of carbon dioxide storage was calculated by using both solid weight increase through the carbonation reaction and the contents of carbonate salts from thermal gravimetric analysis. PSA particle used in this study contained 67.2% of calcium. The optimum sea water content and reaction time in the carbonation reaction using sea water and PSA were 5 mL/g and 2 hours, respectively, under the conditions of 0.05 L/min flow rate of carbon dioxide injected at $25^{\circ}C$ and 1 atm. The amounts of carbon dioxide stored when sea water and ultra-pure water were separately used as solvents in the direct carbonation with PSA were 113 and $101kg\;CO_2/(ton\;PSA)$, respectively. The solid obtained through the carbonation reaction using sea water and PSA was composed of mainly calcium carbonate in the form of calcite and a small amount of magnesium carbonate. The solid obtained by using ultra-pure water, also, was found to be carbonate salt in the form of calcite.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.213-220
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• 1995

Geochemistry of stream water and sediment collected in the vicinity of the Donghae coal mine in the Samchuk coalfied were investigated in order to evaluate the environmental impacts of acid mine drainage. The pH of stream water ranges from 2.85(at 2 km away from the mine) to 7.92(at uncontaminated tributary). The main cation and anion species in the upper stream are $Ca^{2+}$ and $SO_{4}{^2-}$, respectively. The level of pH and the amount of $HCO^{3-}$ in stream water increase to the downstream and where uncontaminated small tributaries are joining, and in the area covered with limestone. From the results of thermodynamic calculation, the main forms of iron in stream water are estimated as $Fe^{2+}$ and $FeSO_{4}{^0}$, and most of them could be precipitated as FeO(OH) with increase of pH. The white precipitates in stream sediments particularly found around the coal mine are proved to be $Al(OH)_3$ by XRD and XRF analysis. As a result of investigation for seasonal variation of AMD, the level of pH decreased and conductivity increased in dry season.

• Mineral and Industry
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• v.29
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• pp.56-66
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• 2016

In Korea, where hydrothermal alteration zones are widely distributed, clay veins formed by hydrothermal alteration processes on natural slopes or artificial slopes can play an important role in the slope stability. When the surface water infiltrates the ground where the clay vein exists, the pore water pressure in the ground can be locally increased due to impermeable properties of clay minerals. Infiltration of the surface water induces the increase in the pore water pressure, which can cause erosion of the fine clay particles. The eroded clay particles flow and deposit in an area where the flow velocity is slowed down. Where clay minerals are deposited, ground water can leak due to an increase in local pore pressures, which can cause slope failure. In this paper, studies related to hydrothermal clay vein and landslide are introduced.