• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.98-105
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• 2005

Groundwater sampled from 24 tube wells of three districts namely Sherpur, Gaibandha and Naogaon in Bangladesh was appraised for their water quality for irrigation and agro-based industrial usage. All waters under test were slightly alkaline to alkaline (pH = 7.2 to 8.4) in nature and were not problematic for crop production. As total dissolved solid (TDS), all groundwater samples were classified as fresh water (TDS<1,000 mg/L) in quality. Electrical conductivity (EC) and sodium adsorption ratio (SAR) values reflected that waters under test were under medium salinity (C2), high salinity (C3) and also low alkalinity (S1) hazard classes expressed as C2S1 and C3S1. As regards to EC and soluble sodium percentage (SSP), groundwater samples were graded as good and permissible in category based on soil properties and crop growth. All water samples were free from residual sodium carbonate (RSC) and belonged to suitable in category. Water samples were under soft moderately hard, hard and very hard classes. Manganese, bicarbonate and nitrate ions were considered as major pollutants in some water samples and might pose threat in soil ecosystem for long-term irrigation. For most of the agro-based industrial usage, Fe and Cl were considered as troublesome ions. On the basis of TDS and hardness, groundwater samples were not suitable for specific industry. Some water samples were found suitable for specific industry but none of these waters were suitable for all industries. The relationship between water quality parameters and major ions was established. The correlation between major ionic constituents like Ca, Mg, K, Na, $HCO_3$ and Cl differed significantly. Dominant synergistic relationships were observed between EC-TDS, SAR-SSP, EC-Hardness, TDS-Hardness and RSC-Hardness.

• Economic and Environmental Geology
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• v.34 no.4
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• pp.329-343
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• 2001

The deep environment and geochemical evolution of the Bugok geothennal waters, located in the Kyeongnam Province, was re-interpreted based on the hydrochemical and isotopic data published by Yun et al. (1998). The geothermal waters of the Bugok area is geochemically divided into three groups; Geothennal water I, II and III groups. Groups I and II are geochemically similar; high temperature (55.2-77.2$^{\circ}$C) and chemically belonging to Na-S04 types. However, pH and Eh values are a little different each other and Group II water is highly enriched in S04 compared to Group I water. Group III water, occurring from peripheral sites of the central part of the geothennal waters, shows temperature range of 29.3 to 47.0$^{\circ}$C and belongs to $Na-HCO_3-S0_4$ types. The deep environment and geochemical evolution of the Bugok geothennal waters, showing the diversity of geochemistry, can be interpreted as follows; I) Descending to great depth of meteoric waters that originated at high elevation and reacting with sediments and/or granites in depth. The $S0_4$ concentration of the waters has been increased by the dissolution of sulfate minerals in sediments. 2) During the continuous descending, the waters has met with the reduction environment, producing the $H_2S$ gas due to sulfate reduction. The waters has been heated up to 130$^{\circ}$C and the extent of water-rock reaction was increased. At this point, pH of waters are increased, S04 concentration decreased and calcite precipitated, therefore, the waters show the $Na-S0_4$ type. 3) Ascending of the geothennal waters along the flow path of fluids and mixing with less-deeply circulated waters. The $S0_4$ concentration is re-increased due to the oxidation of $H_2S$ gas and/or sulfide minerals in sediments. During continuous ascending, these geothennal waters are mixed with shallow groundwater.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.411-420
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• 2016

The objective of this study was to determine the effect of drinking water containing trimethyl glycine or ascorbic acid on growth performance and blood parameter profiles of duck exposed to scorching heat stress. A total of 480 ducks were randomly assigned to the following eight experiment groups for 42 days : control group C with general water, treatment group 1 (T1) with drinking water containing 100 ppm ascorbic acid, treatment group 2 (T2) with drinking water containing 200 ppm ascorbic acid, treatment group 3 (T3) with drinking water containing 300 ppm ascorbic acid, treatment group 4 (T4) with drinking water containing 400 ppm trimethyl glycine, treatment group 5 (T5) with drinking water containing 800 ppm trimethyl glycine, treatment group 6 (T6) with drinking water containing 1,200 ppm trimethyl glycine, treatment group 7 (T7) with electrolytes of KCl (0.5%) + $NaHCO_3$ (1.0%)+NaCl (0.5%). Our results revealed that the body weights and feed intakes of treatment groups, especially T3 and T6, were increased compared to the control group, where as the feed conversion ratios of treatment groups were decreased (p<0.05). Blood levels of total cholesterol, triglyceride, LDL-C, glucose, AST, ALT and pH in treatment groups were lower compared to those in the control group (p<0.05). Blood levels of red blood cell, platelets profiles, electrolyte and gas in treatment groups were higher compared to those of the control group (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.11
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• pp.1462-1468
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• 2010

The effects of vitamin C and vitamin E with selenium on acid-base balance and some stress hormones were evaluated during heat stress in goats. Goats, 1.5 years of age, were divided into control, heat stress and antioxidant treatment groups 1, 2 and 3. Except for the control, all groups were exposed to a temperature of $40{\pm}2^{\circ}C$ with a relative humidity of 30% for 5 h/d for 21 days in a psychrometric chamber. Rectal temperature and respiratory rates were recorded daily post exposure. Blood samples were collected on every 3rd day for estimation of plasma vitamins C and E, total antioxidant activity and hormones, and separate blood samples were taken to estimate acid-base status. The rectal temperature and respiratory rates were increased (p<0.05) in the heat stress group only. Except for pH and $pO_2$, which were increased significantly (p<0.05) other parameters of acid-base balance such as $pCO_2$, $HCO_3^-$, $TCO_2$, BEb, BEcef, PCV and Hb were significantly decreased (p<0.05) in the heat stress group. An improvement in acid-base status was noted in the antioxidant supplemented groups. Prolactin and cortisol levels were significantly (p<0.05) higher and free T3 and T4 levels were significantly (p<0.05) lower in the heat stress group. Levels of prolactin and cortisol were decreased and free T3 and T4 were increased in antioxidant treatment groups. Different levels of antioxidant supplementation resulted in similar protection against heat stress.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1260-1268
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• 2013

A series of experiments were carried out with three native strains of microalgae to measure growth rates, biomass, and lipid productivities. Scenedesmus sp. IMMTCC-6 had better biomass growth rate and higher lipid production. The growth, lipid accumulation, and carbon dioxide ($CO_2$) consumption rate of Scenedesmus sp. IMMTCC-6 were tested under different NaOH concentrations in modified BBM. The algal strain showed the maximum specific growth rate (0.474/day), biomass productivity (110.9 mg $l^{-1}d^{-1}$), and $CO_2$ consumption rate (208.4 mg $l^{-1}d^{-1}$) with an NaOH concentration of 0.005 M on the $8^{th}$ day of cultivation. These values were 2.03-, 6.89-, and 6.88-fold more than the algal cultures grown in control conditions (having no NaOH and $CO_2$). The $CO_2$ fixing efficiency of the microalga with other alternative carbon sources like $Na_2CO_3$ and $NaHCO_3$ was also investigated and compared. The optimized experimental parameters at shake-flask scale were implemented for scaling up the process in a self-engineered photobioreactor. A significant increase in lipid accumulation (14.23% to 31.74%) by the algal strain from the logarithmic to stationary phases was obtained. The algal lipids were mainly composed of $C_{16}/C_{18}$ fatty acids, and are desirable for biodiesel production. The study suggests that microalga Scenedesmus sp. IMMTCC-6 is an efficient strain for biodiesel production and $CO_2$ biofixation using stripping solution of NaOH in a cyclic process.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.303-306
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• 2006

Using a variety of chemical geothermometers we estimate the temperature of a deep geothermal reservoir in relation to thermal groundwater in the Bugok area, southern Korea, in order to assess the potential use of geothermal energy in South Korea. Thermal water at Bugok has been exploited down to about 400 m below the land surface and shows the highest outflow temperatures (up to $78{\circ}C$) in South Korea. Based on the hydrochemical data and occurrence, groundwater in Bugok can be classified into three groups: $Na-SO_4$ type thermal groundwater (CTGW) occurring in the central part (about 0.24 $km^2$) $Ca-HCO_3$ type cold groundwater (SCGW) occurring in shallow peripheral parts of CTGW; and the intermediate type groundwater (STGW). CTGW waters are typical of thermal water in the area, because they have the highest outflow temperatures and contain very high concentrations of Na, K and $SiO_2$ due to the sufficient reaction with silicate minerals in deep reservoir. Their enriched $SO_4$ was likely formed by gypsum dissolution. The major ion composition of CTGW shows the general approach to a partial equilibrium state with rocks at depth. The application of various alkali ion geothermometers yields temperature estimates in the range of 88 to $198{\circ}C$ for the thermal reservoir. Multiple mineral equilibrium calculation indicates asimilar but narrower temperature range between about 100 and $155{\circ}C$. These temperature estimates are not significantly higher than the measured outflow temperatures for CTGW Considering the heat loss during the ascent- of thermal waters, this fact may suggest that a thermal reservoir in the study area is likely located at relatively shallow depths (possibly close to the depth of preexisting wells). Therefore, we suggest a high potential for geothermal energy development around the Bugok area in southern Korea.

• Economic and Environmental Geology
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• v.28 no.2
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• pp.165-176
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• 1995

Dongrae is one of the most famous hot spring resort area in the Republic of Korea. The water temperature ranges $50^{\circ}C{\sim}66$. The chemical composition of the thermal water is quite different from normal groundwater. $Na^+$ and $Cl^-$ are the main components, measured more than 75%, $Ca^{+{+}}$ is contained about 22% and the other ions such as $SO_4$ or $HCO_3$ are the minor components. The heat source is uprising along the fracture zone of granite which is indicated as a subsurface high temperature belt. During the research period of 1991~1992, the groundwater table was lowered down to the depth of about 100 m according to continuous increase of daily use of thermal water. The groundwater table was fluctuated with an amplitude of day, weak or seasion. The groundwater table was the lowest at 18:00 h in a day and also lowest at the weekend for the week period. There was a relavent relationship between drawdown and the amount of thermal water use on a long term base. To protect such a rapid drawdown of groundwater table, Dongrae resort area is now asked to take strong municipal control for the daily use of thermal water.

• Korean Journal of Animal Reproduction
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• v.8 no.2
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• pp.110-115
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• 1984

These experiments were carried out to obtain the information about the optimal pH osmolality affecting in vitro fertilization of the mouse eggs, to elucidate the 2-cell block to development in vitro and to find out the method of controlling the subsequent embryo development in vitro. pH and osomlality was adjusted by adding NaCl or NaHCO3 to the basic salt solution. In vitro fertilization were carried out by inroducting the cumulus masses to the suspension of epididymal spermatozoa at each pH, osmolality, and 10${\mu}$M-EDTA medium. The results obtained in these experiments were summarized as follows: 1. The fertilization rates in vitro at each medium of 235, 252, 269, 286, 306, 323, 345, 368, 393 mosmol were 15.6, 38.2, 65.7, 75.6, 80.9, 74.3, 58.1, 35.1, 24.3, 11.1%, respectively. 2. The fertilization rates in vitro at each medium of pH 6.1, 6.4, 6.7, 7.0, 7.3, 7.6, 7.9, 8.1 were 11.8, 17.9, 32.4, 61.9, 79.5, 76.7, 53.5, 13.6%, respectively. 3. In case of ICR female x ICR male embryos, the development rate of 2-cell embryos to 4-8 cell embryos was 16.2% at normal medium, but the rate was increased to 49.3% in medium containging 10 ${\mu}$M-DETA; In case of C3H female x ICR male embryos, the development rate was 41.0% at normal medium, but the rate was increased to 71.7% at 10 ${\mu}$M-EDTA-medium.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.60.1-60.1
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• 2010

Methanol maser sources are believed to represent the earliest evolutionary stage of massive star formation. Pandian et al. (2007) recently made a very sensitive blind survey of 6.7GHz ClassII methanol maser towards the Galacitic midplane ($35^{\circ}$<1<$55^{\circ}$ & |b|<$0.5^{\circ}$) and found 86 maser sources. We carried out 22GHz $H_2O$ and 44.0 GHz $CH_3OH$ maser line surveys of them with KVN 21m and various (CO (2-1), $^{13}CO$ (2-1), $^{13}CO$ (1-0), $C^{18}O$ (2-1), CS (2-1), $HCO^+$ (3-2) and HCN (3-2)) molecular line surveys with SRAO 6m and TRAO 14m. we will present the preliminary results and discuss the implications for massive star formation.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.33.1-33.1
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• 2017

Molecular clouds are the sites of stellar birth, and conditions within the clouds control the mode and tempo of star formation. In particular, turbulence largely determines the density and velocity fields, and can affect the gas kinetic temperature as it decays via shocks. However, despite its central role in star formation and many years of study, the properties of turbulence remain poorly understood. As a part of the TRAO key science program, "Mapping turbulent properties of star-forming molecular clouds down to the sonic scale (PI: Jeong-Eun Lee)", we mapped the northern region of the Orion A molecular cloud and the L1688 region of the ${\rho}$ Ophiuchus molecular cloud in 2 sets of lines (13CO 1-0/C18O 1-0 and HCN 1-0/and HCO+ 1-0) using the Taeduk Radio Astronomy Observatory (TRAO) 14-m telescope. We analyze these maps using a python package 'Turbustat', a toolkit which contains 16 different turbulent statistics. We will present the preliminary results of our TRAO observations and various turbulence statistical analyses.