• Journal of the Korean GEO-environmental Society
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• v.2 no.2
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• pp.5-12
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• 2001

The physical characteristics and contaminant level of the dredged material generated by the channel maintenance and water quality improvement was analysed in a series of the study of the beneficial uses of dredged material in harbor. Dredged materials were sampled at Kunsan, Kohyun, Samchunpo, and Pohang Harbors and tested in the laboratory(leaching Test). From the experimental results, the specific gravity does not shows large differences, while almost grains are composed of silts and oyster shells except Pohang harbor containing gravels. The COD release rate and ignition loss is high in Kunsan dredged materials because of the watershed pollutants loads. The nutrient release rate is also relatively high. The release concentration of the heavy metals shows the highest values on Zn, Pb, Cd, Cu constituents at Kohyun, Kunsan, Samchunpo, Kunsan, respectively.

• The Korean Journal of Malacology
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• v.29 no.1
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• pp.33-41
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• 2013

This study investigated concentration of metal ions, intersexuality and histological alterations of digestive gland in Mytilus galloprovincialis. Samples were collected from two areas of Gamak Bay in May, 2010. The concentration of metal ions showed that Al ($366.5{\pm}249.7$ mg/kg) was highest and Zn ($179.5{\pm}67.8$ mg/kg) was second high concentration. Co ($1.0{\pm}0.2$ mg/kg) was lowest. The intersexuality was 26.4% and males (38.8%) was higher than the females (12.9%). Intersex type was observed four types. Destruction of digestive tubule epithelium was highest among other biomarker in digestive gland. Distribution of basophilic cell and lipofuscin was 6.1% and 1.5%, respectively.

• Clean Technology
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• v.17 no.4
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• pp.353-362
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• 2011

In our nature, the utilization of rainwater is essential for healthy water recirculation. This is one of the solutions of the increment of impermeability surface according to the development of new cities; this study of the improvement of rainwater quality has been carried on through the improvement of collecting and restoring system of rainwater. The southwestern region of Daejeon City, the rainwater coefficient of run off was 0.40 and this number had computed to 0.59 after the development. After filtration of rainwater, the heavy metal (Cu, As, Cr, Fe, Mn) contents level were lower than underground water. Moreover, collected rainwater showed better quality than underground water in following criteria; hardness, permanganate consumption quality, chloride, evaporation residue, sulfates and nitrate nitrogen. This water quality met the gray water quality standards. The rainwater quality was still suitable to use as bathroom flushing and gardening after 100 days of storage. This study proved that modification (installation of cover with gutter to existing rainwater collection system, proper filtering, and installation of underground storage tank) of collection system could improve quality of water and maintain this approximately 100 days.

• 한국지구물리탐사학회:학술대회논문집
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• 2001.09a
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• pp.75-89
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• 2001

There are 334 coal mines and about 900 metal mines abandoned. The environmental problems such as acid mine drainage from adits etc. and the subsidence has occurred in the abandoned mines. In addition, soil has been contaminated by tailings. According to analysis of mine drainages, some of them from adits in the abandoned coal and metallic mines were acidic and polluted by heavy metals. Especially, water quality of coal mine drainages were different by areas. Treatment of mine drainage by conventional chemical treatment has the drawback because the operating cost is very expensive. The treatment system used in mine drainage is the natural treatment system such as anoxic limestone drain in adits and the constructed wetland. The method of reclamation for abandoned waste rocks and tailings impoundments are mainly landfilling.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.337-343
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• 2008

따개비류는 암반기질에 무리를 이루어 비교적 단단히 부착생활을 하며 전 세계적으로 분포하는 생물이다. 본 생물은 형태가 다른 두 단계의 플랑크톤 유생시기를 거쳐 기질에 부착하여 생활한다. 따개비류에 관한 국내연구는 순수 분류학적으로 몇 편의 연구가 이루어졌을 뿐이며 실험실 내 사육조건 및 유생의 민감도 등에 관한 연구는 제대로 수행되어 있지 않은 실정이다. 본 연구에서는 첫 번째 단계 유생을 대상으로 몇몇 중금속(Cd, Cr, Cu 그리고 Zn)에 대한 민감도를 조사하였고 타 연구결과와의 비교로 생태 독성학적 적용을 시도하였다. 네 가지 금속물질, 카드뮴, 크롬, 구리 그리고 아연에 대한 따개비 유생의 반수사망농도는 각각 0.43, 24.4, 0.22 그리고 1.74mg/L로 산정되었다. 외국의 생물검정용 따개비와 본 연구에 사용된 고랑따개비의 민감도는 아주 유사하게 나타났다. 따라서 국내산 고랑따개비의 유생은 해양 환경 평가에 일반적으로 이용되는 해양생물과 동반 검정의 수행에 자격을 갖추었다고 할 수 있다. 본 연구의 결과는 해양환경의 평가는 물론 방오물질개발 등에의 기초자료를 제공할 수 있을 것으로 사료된다.

• Journal of Food Hygiene and Safety
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• v.17 no.3
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• pp.146-151
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• 2002

The contents [average(minimum∼maximum), Unit:mg/kg] of hazardous heavy metals(Hg, Cd and Pb) were estimated from 951 fishery products in Seoul(468 fishes,373 shellfishes, 39 crustaceans and 71 others) from January to December in 2001 by Atomic Absorption Spectrometer. Hg contents showed in shellfishes [0.033(N.D.∼0.19)]>others(0.026(N.D.∼0.11)]>crustaceans[0.026(N.D.∼0.09)]>fishes[0.018(N.D.∼0.19)], Misgurnus mizolepis(0.19) and Tegillarca granosa(0.19) were the highest. Pb content were shellfishes [0.223(N.D.∼l.38)] >fishes[0.213(N.D.∼1.68)]>others[0.15(N.D.∼0.39)]>crustaceans[0.144(N.D.∼0.444)], and Misgurnus mizolepis (1.68)>Hypomesus olidus(1.44)>Tapes philippinarum(1.38)>Anguilla japonica(1.35). Also, Tegillarca granosa(1.85) was the most Cd contents among shellfishes[0.288(N.D.∼1.85)].

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.388-394
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• 2012

The present study was carried out to assess the dietary exposure and the risk for arsenic (As) and mercury (Hg) through mushrooms intake. Various samples (n = 536) covering 17 kinds of mushrooms were collected from retail outlets and markets in Korea. The contents of As were 0.003 (King oyster) ~ 1.952 (Matsutake) mg/kg in raw mushrooms and 0.015 (Fuscoporia obliqua) ~ 16.95 (Matsutake) mg/kg in dry mushrooms, respectively. The contents of Hg were 0.001 (King oyster) ~ 0.030 (Matsutake) mg/kg in raw mushrooms and 0.004 (Oyster) ~ 0.588 (Matsutake) mg/kg in dry mushrooms, respectively. The mean dietary exposures of As was $0.151{\mu}g$/day, taking 0.005% of provisional tolerable weekly intake (PTWI). The mean dietary exposures of Hg was $0.022{\mu}g$/day, corresponding to 0.071% of PTWI. Therefore, the level of overall dietary exposure to As and Hg for Korean population through mushroom was far below the levels recommended by Joint FAO/WHO Expert Committee on Food Additivies, indicating little possibility of concern.

• Resources Recycling
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• v.13 no.4
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• pp.3-10
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• 2004

The intension of this study is to produce ordinary portland cement using ash, both bottom ash and fly ash, obtained from municipal solid waste incineration ash (MSWI). We used limestone, waste molding sand, shale, slag from converting furnaces and fly ash as main raw materials and mixed them, setting the lime saturation factor (LSF) within 91.0, the silica modulus (SM) within 2.40, and iron modulus (IM) within 1.80. We conducted tests adding bottom ash alone 1, 2 and 3％ by weight, respectively, and a mixture of bottom ash 0.9％ and fly ash 0.1 ％ by weight. The result of analysis on clinker shows that the more ash is added, the lower the burnability index (B.I.) falls, lowering the mineral evolution of calcium silicate accordingly. From the measurement of compressive strength we have learned that the more ash is used, the lower the strength becomes.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.109-115
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• 2001

Silk sericin protein was extracted by treatment with enzyme or NaOH solution from raw silk and culled-cocoon shell. The extracted sericin was characterized and examined the functional properties as well as subjective properties for its use as a soap and a body cleaner. The optimum extraction conditions on specimen are NaOH (0.02 wt.%) or enzyme, Flavourzyme 3% under N2 gas. Molecular weights of sericin was decreased by treatment with enzyme, Actinase, from 10,000-30,000 to 2,700-4,200. Sericin showed important bioactive properties, for instance, lowering effect on blood glucose and alcohol. Subjective test of sericin soap and body cleaner showed superior in washability, foamability, and skin hydration, etc., to commercial soap and body cleaner. Therefore, it is thought that silk sericin can be expected as the source of bioactive and skin-compatible materials.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.1
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• pp.16-23
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• 2021

Lithium carbonate recovered from the waste solution generated during the lithium secondary battery manufacturing process contains heavy metals such as cobalt, nickel, and manganese. In this study, the recrystallization of lithium carbonate was performed to remove heavy metals contained in the powder and to increase the purity of lithium carbonate. First, the leaching efficiency of lithium carbonate according to pH in the aqueous hydrochloric acid solution was examined, and the effect on the recrystallization of lithium carbonate according to the equivalent and concentration of sodium carbonate was confirmed. As the equivalent and concentration of sodium carbonate increased, the recovery rate of lithium carbonate improved. And the SEM image showed that the crystal shape was changed depending on the reaction conditions with sodium carbonate. Finally, the high purity lithium carbonate of 99.9% or more was recovered by washing with water.