• Resources Recycling
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• v.28 no.3
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• pp.35-44
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• 2019

In this study, we conducted experiments to store $CO_2$ and produce $CaCO_3$ through indirect carbonation using paper sludge ash (PSA) and three chelating reagents (fumarate, IDA and EDTA). Fumarate and IDA used as solvents could facilitate the indirect carbonation reaction to store more $CO_2$ than water. When 0.1 M fumarate and IDA were used, $CO_2$ storage was 63 and $89kg-CO_2/ton-PSA$, respectively, and $CaCO_3$ yield was 144 and $202kg-CaCO_3/ton-PSA$. For the case of EDTA, however, the carbonation was hardly progressed. As either the concentration or Ca-ligand stabilization constant of each chelating reagent increased, the calcium extraction efficiency from PSA increased. In addition, the carbonation efficiency was influenced by the Ca-ligand stabilization constant. As the Ca-ligand stabilization constant increased, more calcium could be extracted from the PSA. With the constant larger than that of $CaCO_3$ ($10^{8.35}$), however, the carbonation reaction was not proceeded.

• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.375-380
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• 1998

A study of characteristics of greenish pigments from silkwarm excrement by ethanol extraction. Through visible absorption scanning, it showed two absorption peaks at 415 and 657nm, and it was shown to be greenish color. In the presence of light, the stability of pigments rapidly degraded, but in the presence of Al-foil, green and blue cover were very stable. It was shown to be stabilized at the temperature of 7$0^{\circ}C$ until 20days and presence of metal ions, such as Na+, K+, Ca2+, Mg2+ and Zn2+. The pigments was shown to be stabilized in 5% acetic acid solution, but in the presence of lactic acid, citric acid and tartaric acid solution were unstable. On the result of TLC analysis, pigments were shown to be composed of eight color fractions, and main color fractions were F-1, F-2 and F-3. In F-1, F-2 fractions were revealed green color and F-3 fraction were revealed yellow color.

• Journal of the Korean Applied Science and Technology
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• v.24 no.3
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• pp.301-308
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• 2007

From the experiment result on pharmacetical characteristics and analysis of Garlic extract, some conclusions were obtained as follows. From the results on extract experiment of Garlic, extraction ratio was about 6.0%, and after dried with dry oven from Garlic extract, it obtained about 50%-Garlic extract of solid state. From results on antimicrobial experiment of Garlic extract, number of staphylococcus and fungus in microbe decreased more and more according to time passage. This phenomenon showed that Garlic extract keeps antimicrobial effect. From results on antioxidation experiment of Garlic extract, DPPH scavenging activity of free radical showed that Garlic extract appears more remarkable reduction ability than reference samples. This phenomenon means that antioxidation of Garlic extract appears higher than Vitamin-C and BHA. From results on instrument analysis, inorganic components of K, Na, Ca, Si, Mg, Zn etcs from Garlic extract were detected with ICP/OES and the fatty and aromatic components of trimethyl sulfide, diallyl disulfide, diallyl trisulfide, 2-mercaptobenzothiazole etcs from Garlic extract were detected with GC/MS.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.20-23
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• 2005

The objective of this study is to examine a stabilized efficiency of heavy metals including Cd, Cu, Pb and Zn using slaked lime. Tailings from the Janggun Pb-Zn mine, the second Yeonhwa Pb-Zn mine, the Jisi Au-Ag mine and the Sangdong W mine were sampled and measured heavy metal concentrations contents using AAS as various extraction methods. During 156 hours, column test were undertaken to evaluate the possibility of stabilization by slaked lime. The result shows that $Ca(OH)_2$ has a good efficiency in heavy metal stabilization, especially at the Jisi mine with stabilized efficiencies of 97%(Cd), 99%(Cu), 86%(Pb) and 99%(Zn), respectively.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.157-160
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• 2000

Solubilization of bovine serum albumin(BSA) is performed using a reverse micellar system consisting of sodium bis(2-ethylhexyl) sulfosuccinate(AOT). Of particular, effects of pH, salt concentration and its type on the solubilization are investigated by means of the phase-transfer method. One of significant findings in our study is that the protein is to a large extent aggregated in the interface between organic and aqueous phases at lower pH and small salt concentration. In this presentation, the optimal extraction process conditions for BSA, which is bulky, are proposed.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.280-282
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• 2001

인터넷의 발달로 웹에서 제공되는 정보와 서비스의 양이 폭발적으로 증가하고 있다. 따라서 사용자들은 보다 쉽게 빠르게 정보를 찾을 수 있도록 지원해 주는 정보 검색 에이전트에 대한 개발을 요구하고 있다. 본 논문에서는 사용자에게 적합한 도서 정보를 검색 및 추천하는 멀티 에이전트 시스템을 설계한다. 그리고 여러 에이전트 사이의 행동을 제어하는 CA(Coordination Agent) 에이전트의 조정 기능과 각 에이전트간의 통신을 지원하는 KQML처리의 알고리즘을 구현한다. 구현 결과 CA의 Message Queue 비교를 토한 조정 기능은 IEA(Information Extraction Agent)의 중복된 정보검색을 방지하여 보다 빠르고 효율적인 정보 검색의 효과를 얻을 수 있었고, KQML은 JAVA의 클래스로 구현하여 본 시스템에서 사용된 메시지 이외의 모든 KQML 메시지 처리 기능을 포함할 수 있도록 하였다.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1557-1561
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• 2006

The use of chemically modified silica-salen$(NEt_2)_2$ was studied for the separation and concentration of the metal ions from an aqueous solution by a solid phase extraction. After the salen(NEt2)2 was synthesized, it was chemically bonded to silica gel by a diazonium coupling reaction. The adsorption capacities and binding constants were obtained with respect to Cu(II), Mn(II), Pb(II) and Zn(II) by a graphical method. Some experimental conditions were optimized for the determination of the trace elements. After the silica-salen(NEt2)2 was pulverized in a sample solution of which the pH was adjusted, the solution was stirred to pre-concentrate the metal ions. The metal ions adsorbed were desorbed with nitric acid solution. And the concentrated analytes were determined by a flame AAS. The method proposed here was so rarely influenced by a sample matrix that the procedure was applied to 3 types of water samples. The reproducible results of less than 10% RSD were obtained at the concentration level of ca. 100 ng/mL and the recoveries of 95-109% were obtained in the spiked samples in which given amounts of analytes were added.

• KSBB Journal
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• v.14 no.5
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• pp.566-571
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• 1999

Lactic acid is of interested as the raw material of biodegradable polymer. In this study lactic acid was separated by reactive extraction with mixed tertiary amine extractant dissolved in 1-octanol/n-heptane. Mixed tertiary amine extractant was composed of tripropylamine(TPA) and trioctylamine(TOA). The concentration range of lactic acid is ca. 5wt% which is the concentration of lactic acid obtained from fermentation.Maximum distribution coeficient was obtained at 8:2 weight ratio of TPA/TOA and their extraction efficiencies were above 90%.

• Journal of Environmental Science International
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• v.9 no.5
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• pp.437-441
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• 2000

A study on the removal of Pb ion from Pb-contaminated soil was carried out using ex-site extraction process. Tartaric acid (TA) and iminodiacetic acid sodium salt(IDA) as a washing agent were evaluated as a function of concentration reaction time mixing ratio of washing agent and recycling of washing agent. TA showed a better extraction performance than IDA. The optimum washing condition of TA and IDA were in the ratio of 1:15 and 1:20 between soil and acid solution during 1 hr reaction. The total concentrations of Pb ion by TA and IDA at three repeated extraction were 368.8 ppm and 267.5 ppm respectively. The recovery of Pb ion from washing solution was achieved by adding calcium hydroxide and sodium sulfide form the precipitation of lead hydroxide and lead sulfide and optimum amounts of sodium sulfide and calcium hydroxide were 7 g/$\ell$ for the TA washing solution and 4 g/$\ell$, 5g/$\ell$ for the IDA washing solution respectively. The efficiency of recycle for TA and IDA washing solution were 78.8% , 95.1%, and 89.2%, 96.6% at third extractions under $Na_2S$ and $Ca(OH)_2$, respectively.

• Korean Journal of Environmental Agriculture
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• v.21 no.3
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• pp.223-228
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• 2002

In addition to supplying the essential elements, Ca and S, phosphogypsum can have profound effect on both the physical and chemical properties of certain soils. However, no widespread use of by-product phosphogypsum will be made unless such uses pose no threat to the public health and soil contamination. In this study, the extractability of As, Cd, Cu, and Pb with water and DTPA solution from phosphogypsum samples of pH 3, 5, and 7 were investigated to estimate the availability of those metals. Contents of water extractable metals in ohosphogypsum were less than 5 mg/kg for all the heavy metals investigated. The extractability of metals in DTPA solution was not quite different but a little higher in comparison to the water extraction. And the extractability was decreased as the pH of phosphogypsum increased. In the phosphogypsum of pH 7, amounts of water extractable metals were nearly zero. There was no significant difference in the amount of extractable metals during the extraction period of 5 weeks. The length of extraction time did not affect heavy metal extractability. Therefore there may be small fractions of easily soluble or extractable forms of metals in the phosphogypsum and most of the metals would be present in very insoluble forms. These results suggest that the application of phosphogypsum at appropriate rates on agricultural lands appears of no concern in terms of hazardous element contamination in soil.