• The Korean Journal of Food And Nutrition
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• v.13 no.4
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• pp.383-389
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• 2000

Stabilities to heat, pH, light were investigated about isolated red color pigment from the Korean Lithospermum erythrorhizon. The extracted pigment, acetylshikonin was stable heating at 40∼80$\^{C}$ for 1∼2 hours, hut it was specially unstable on the storage above 55$\^{C}$. The extracted pigment, acetylshikonin was stable on the sunlight under the red and green filters but unstable under the yellow and blue filters. The extracted pigment, acetylshikonin was stable under the pH of 4∼8 but unstable under the pH above 10. The extracted pigment, acetylshikonin was stable under the KCl and NaCl at concentration of 10$\^$-1/Mole. The pigment was very unstable under the CaCl$_2$, FeCl$_3$, CoCl$_2$, AlCl$_3$ and MnCl$_2$ at concentration of 10$\^$-1/Mole. The red pigment, acetylshikonin was stable under citric acid and acetic acid at concentration of 1 Mole. Especially, acetic acid was effective for the stability of the pigment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.2
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• pp.24-28
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• 2006

Electrochemical hydrogenation/dehydrogenation properties were studied for a single particle of a Mm-based(Mm : misch metal) hydrogen storage alloy($MmNi_{3.55}Co_{0.75}Mn_{0.4}Al_{0.3}$) for the anode of Ni-MH batteries. A carbon fiber microelectrode was manipulated to make electrical contact with an alloy particle, and the cyclic voltammetry and the galvanostatic charge/discharge experiments were performed. A single particle of the alloy showed the discharge capacity of 280[mAh/g], the value being 90[%] of the theoretical capacity. Data were compared with that of the composite film consisting of the alloy particles and a polymer binder, which is more practical form for Ni-MH batteries. Additionally, pulverization of the alloy particles are directly observed. Compared with the conventional composite film electrodes, the single particle measurements using the microelectrode gave more detailed, true information about the hydrogen storage alloy.

• Journal of Korean Society on Water Environment
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• v.28 no.2
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• pp.277-284
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• 2012

This study developed a new ceramics in which natural zeolite was mixed and calcined with industrial by-product such as converter slag, red mud, and fly ash and evaluated the feasibility of the ceramics for removal of heavy metals in acid wastewater. The removal rate of heavy metal by ceramics increased in the order of ZS (zeolite and slag) > ZR (zeolite and red mud) > ZF (zeolite and fly ash) ceramics. The alkalinity increment and coherence of ceramics were increased in the order of ZS > ZR > ZF ceramics. The mixing ratio of natural zeolite to industrial by-product for maximum removal efficiency of heavy metal was 1:1 for ZS ceramics and 1:3 for ZR and ZF ceramics. The order of removal efficiency of heavy metal was observed to be ZS > ZR > ZF ceramics under the mixing ratio of 1:1 for ZS ceramics and 1:3 for ZR and ZF ceramics. The removal efficiency of heavy metal by ZS ceramics with 1:1 mixing ratio was Al 100%, Cd 54.6%, Cr 99.9%, Cu 98.7%, Fe 99.9%, Mn 42.2%, Ni 59.9%, Pb 99.8%, Zn 87.6%, respectively. In addition, the removal capacity of heavy metal by ZS ceramics was observed to be Al 2.01 mM/g, Cd 0.27 mM/g, Cr 1.02 mM/g, Cu 0.83 mM/g, Fe 0.95 mM/g, Mn 0.41 mM/g, Ni 0.55 mM/g, Pb 0.25 mM/g, Zn 0.70 mM/g, respectively. The comparative evaluation in the light of removal capacity, alkalinity increment, and coherence of ceramics showed the ZS ceramics had higher feasibility as a media than others for removal of heavy metals in acid wastewater.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.3
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• pp.213-236
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• 2001

The ionic composition of soil solution is related to a nutrient uptake by plant. Many models for estimating ionic composition of solution have been developed, and most of them have been used for calculating a content of mineral and ionic species in a geochemical point of view. An approximation model considering both cation and anion in soil solution was developed. Variables such as pH, Eh, EC, cations(K, Ca, Mg. Na, Fe, Mn, Al, $NH_4{^+}$), anions(Si, S, P, CY, $NO_3{^-}$, $HCO_3{^-}$ and chemical equilibria of ionic species in soil solution were input into Excel sheet. The activities of soluble ion, ionpairs and complexes of input element were estimated by Newton-Raphson method using conditional equilibrium constant calculated by Davies equation and special models. Equilibrium contents of insoluble minerals and complexes were also calculated.

• Journal of the Korean Electrochemical Society
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• v.2 no.3
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• pp.117-122
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• 1999

This study investigated the corrosion rate of aluminum in alkaline solution. It was performed to observe the effects of alloy element, alkalinity (KOH concentration), solution temperature, and inhibitor and its concentration in the solution. Among species of aluminum, AA-1050 showed the lowest corrosion rate due to its high purity $(>199\%)$, whereas alloys containing Mg anuor Mn were highly corroded, relatively. The corrosion rate could be reduced over than $50\%$ by saturating the solution with ZnO, while ZnAc did not work as an inhibitor. The inhibition effect of ZnO increased with increasing the alkalinity and solution temperature. It was found that the corrosion rate linearly increased with the concentration of KOH in first order and exponentially decreased with the inverse of the solution temperature. An analysis of the corroded material covered the surface of aluminum was made by SEM and EDS. According to the analytical results by using XRD, it was confirmed that $Al(OH)_3$ was produced from the corrosion of aluminum in KOH solution.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.626-637
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• 2013

We measured the grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS) and trace metals (Al, Fe, Cu, Pb, Zn, Cd, Cr, Mn, Hg, and As) of intertidal surface sediment collected from 11 islands (62 stations) in the southern region of Jeollanam Province. The objective of this research was to evaluate the organic matter and trace metals contaminations of sediments from coastal island tidal flats. Surface sediment texture was characterized as follows: mud, sandy silt, muddy sand, and slightly gravelly sand facies. The finer sediments are mainly dominated in the northern part of each island. The concentrations of IL, COD, AVS and some trace metals (Al, Fe, Zn, Cr, Cu, and Hg) were higher in the northwestern part of Wan Island and the area between Gogeum and Sinji Islands, and were associated with relatively finer sediment, as compared to other locations. The concentrations of Mn, Pb, Cd, and As were higher in the northwestern and southeastern parts of Geoguem and Pyungil Islands, but were not correlated with mean grain size. Based on sediment quality guidelines (SQGs), the concentrations of trace metals were lower than the values of effect range low (ERL), used in United States, and threshold effects level (TEL), used in Korea, with exception of As. Similarly, the intertidal sediments were moderately contaminated with As, based on the the enrichment factor (EF) and the geoaccumulation index ($I_{geo}$). The high concentration of As in intertidal sediments from this study region may be due to the input of naturally or artificially contaminated submarine groundwater, contaminated waste from seaweed aquaculture operations and/or land-based seaweed processing facilities. Further studies are needed to identify the sources of As in this study region, and to determine the effects of As contamination on coastal ecosystem.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.198-207
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• 1999

Five core sediments acquired from the Lake Shihwa are analyzed for variations of sedimentary environment and heavy metal pollution after the Shihwa seawall construction. The depositional environment of the study area is divided into anoxic, oxic and mixed suboxic conditions based on the C/N ratio and C/S ratios of organic matters. Controlling factors for redox condition are the water depth and the difference in industrial effluents supply. Correlations among geochemical elements (Mn, U, Mo) show a distinctive difference and thus can be used as an indicator of redox condition. The content of Al, Ti are dependent on the sediment characteristics, and the contents of heavy metals (Cr, Ni, Cu, Zn, and Pb) indicate heavy metal pollution. The concentrations of heavy metals are higher near Shiswa-Banwol industrial complexies than the central part of Lake Shihwa. Especially, the accumulation of the heavy metal at the surface sediments near Shihwa-Banwol industrial complex are two to eight times higher than in the center of Lake Shihwa.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.204-210
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• 2011

We looked into the content change of microelements participating in the metabolism among the impacts of radiation energy on living bodies. We irradiated X-rays of 1 Gy, 5 Gy and 10 Gy to the whole bodies of mice, and then analyzed the liver tissues. We found that the microelement content had changed in some elements compared with the control group. When it came to changes by radiation dose, there was no significant change with the absorbed level of 1 Gy, but the higher absorbed levels of 5 Gy and 10 Gy reduced the content of Ca and Mn. In particular, the Ca content was reduced the most, apparently causing symptoms such as muscle tension and chronic headache, etc. The increased element was Al, which was found to have increased by 100%. In regard to the content change according to the time elapsed after irradiation, the contents of Fe, Ba, etc. showed the tendency of reduction. The content of Cd, a harmful element, increased by 25%, and it seemed that the element was involved in the calcium metabolism. Therefore, cell damage by radiation energy is determined to have an impact on the content change of microelements and considered to be partly related to a cause of precursor symptoms.

• The Korean Journal of Mycology
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• v.14 no.3
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• pp.209-214
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• 1986

In order to study the trehalase (EC 3. 2. 1. 28) from mushroom, Agaricus bisporus Lange Sing., the crude trehalase preparation was separated by fractionation of mushroom extracts with ammonium sulfate between 0.4 and 1.0 saturation, and its properties were examined. Mushroom trehalase showed optimum pH 6.0, and optimum temperature $40^{\circ}C$. The enzyme was stable at pH range between 5.0 and 7.0, and at temperature below $50^{\circ}C$. The activities of crude trehalase had proportional relations with enzyme concentrations below 490.2 mg % of protein and with substrate concentration below $2.6{\times}10^{-3}M$, showing a Km value of 0.760 mM. The enzyme was inhibited by some metal ions such as $Sn^{2+}$, $Ca^{2+}$, $Hg^{2+}$, $Cd^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Zn^{2+}$, $Al^{3+}$, and $Fe^{3+}$, while $Ag^{+}$, $Ba^{2+}$, and $Mg^{2+}$ demonstrated remarkable increasing effects on the enzyme activity.

• Journal of Soil and Groundwater Environment
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• v.10 no.3
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• pp.16-23
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• 2005

In order to remediate acid mine drainage (AMD) from the Jeongam coal mine, steel mill slag, cow manure and limestone were used. As a result of batch test, the proper amounts for treating 1 L of acid mine water from the mine were determined as 15 g of steel mill slag, 15 g of cow manure and 500 g of limestone. After feasibility test, remediation system was arranged in the order of steel mill slag tank combination of cow manure and limestone, precipitation tank and oxidation tank. During 54 days' operations, the pH values of the treated waters increased from 3.0 to 8.3 and 61 % of sulfate concentration in an initial water was decreased. In addition, the removal efficiencies for metals in the water were nearly 99.9% for Al, Fe, Zn and 92.6% for Mn. Thus, the combination of steel mill slag, cow manure and limestone can be used as neutralization 때d metal removal for acid mine drainage.