• 자원리싸이클링
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• 제27권3호
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• pp.78-85
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• 2018

블랙드로스에 함유된 알루미나를 회수하기 위해 볼밀처리가 염산침출에 미치는 영향을 조사하였다. 볼밀처리 시간과 회전속도는 알루미나 침출에 큰 영향을 미치지 않았다. 최적의 볼밀처리(1시간, 700 rpm)에서 알루미나 침출은 침출시간과 온도에 영향을 받았다. 본 논문의 실험조건에서 산화마그네슘은 모두 용해되었으며, 칼륨, 철, 실리콘과 타이타늄 산화물은 일부만 용해되었다. 알루미나는 80% 정도 침출되었지만 상기 산화물이 미량 용해되므로 순수한 알루미나용액을 회수하기 위해서는 분리공정의 도입이 필요하다.

• Journal of the korean society of oceanography
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• 제39권3호
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• pp.197-206
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• 2004

Mussel, Mytilus galloprovincialis, was transplanted reciprocally between contaminated site (St. STP) and relatively less contaminated site (St. UB) in Onsan Bay, Korea in order to estimate heavy metal accumulation and release. Transplanted and indigenous mussels were collected 8 times over 108 days deployment at both sites and analyzed for Cd, Cu, Pb and Zn using ICP/MS. Cu and Zn concentration did not show any significant differences between transplanted and indigenous mussels throughout the experiment period, although dissolved Cu and Zn concentrations in seawater were significantly higher at contaminated site. Pb accumulated rapidly, while Cd did not show any accumulation in the mussels transplanted from St. UB to St. STP. These accumulation patterns might reflect the variation of dissolved metal concentration; dissolved Pb concentration was significantly higher in St. STP than St. UB, while dissolved Cd concentration was similar between both sites throughout this experiment. Release of Cd and Pb in the mussels transplanted from St. STP to St. UB was not significant during the transplantation period. The levels and variation of Pb and Cd concentrations in mussels transplanted from St. STP to St. UB were similar to those in the indigenous mussels at St. STP throughout the period. Therefore, Cd and Pb accumulated in indigenous mussels may indicate the integrated metals throughout their lives, not responding to the present status of seawater because the release of accumulated metals in mussels occurs very slowly when the seawater metal levels are lowered. On the other hand, since the transplanted mussels can respond immediately to the levels of metals in seawater, it may be suggested that the present status of heavy metals in seawater can be only acquired from the metal levels of mussels transplanted from clean environments.

• 한국환경과학회지
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• 제7권5호
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• pp.623-631
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• 1998

Pyrite contained in wasted ore dumps induces a strong acid environment when it contacts oxygenated rainfall. Present research was designed to evaluate the pollution of an area that is supposedly contaminated by pyrite of ore wasted dumps form in Chonju Il Mine. Measured are the pH and selected heavy metal elements in the supposedly polluted hydrologic system. The samples include three types : those collected from the stream waters; those from the stream sediments; and those from the rice field soil scattered over the area. The dispersion path of the pollution source was also traced. The pH of the hydrologic system ranged from 3.44 to 5.46, which clearly indicates that the area is on the acid environment. The pH tends to rise as the distance from the minehead increases. The content of heavy metal elements dissolved in the stream water varies as follows; Mn=69.73~1.99ppm, Cd=0.02~0.03ppm, Zn=0.77~1.18ppm, Cu=0.04~0.13ppm, Pb=0.22~0.32ppm. The stream water in this state may induce serious heavy metal pollution to the agricultural land and the water for human life especially in the villages down the stream. The content of heavy metal elements dissolved in the stream sediment varies as follows; Mn=245.0~4685.0ppm, Cd=10.0~15.0ppm, Zn=105.0~210.0ppm, Cu=65.0~155.0ppm, Pb=90.0~150.0ppm. The content of heavy metal elements dissolved in the rice field soil varies as follows; Mn=185.0~260.0ppm, Cd=10.0~15.0ppm, Zn=135.0~180.0ppm, Cu=65.0~90.0ppm, Pb=100.0~130.0ppm. The pollution index in the stream sediment and the rice field sell is 1.36~2.03, which shows that pollution had already begun all over the area where the samples were collected.

• 생태와환경
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• 제40권4호
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• pp.537-545
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• 2007

The heavy metal removal capacity of filamentous green alga Cladophora sp. cultured together with wet-mixed solidified soil (loess) was tested. A Cladophora sp. was cultured for 5d, with added Chu No. 10 medium, in stream water contaminated by high concentration of heavy metals from a closed mine effluent. Heavy metal ion concentrations of the medium and in algal tissue were measured every day during the experiment. Dissolved metals (Al, Cd, Cu, Fe, Mn, Zn) in medium were rapidly removed (over 90% elimination) within 1-2d when alga and loess were added. Dissolved heavy metals dropped by only 10% when algae were cultured without loess. The Cladophora sp. accumulated much more heavy metals when cultured with loess than when the alga was cultured alone. Cladophora sp. exhibited a maximum uptake capacity for Al ($17,000{\mu}g^{-1}$ algal dry weight). The metal bioremoval capacities of the algae were in the order Al, Fe, Cu, Mn, Zn and Cd. The heavy metal removal capacity of Cladophora sp. showed significant increases when wet-mixed solidified soil was added to culture media.

• 한국광물학회지
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• 제26권4호
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• pp.219-228
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• 2013

방사성 폐기물을 지하에 장기 보관하는 금속 용기에 관한 생지화학적 부식 특성을 알아보기 위해 주철과 구리로 된 금속재료를 환원조건 하에서 디설프리칸스 황산염환원미생물과 3개월간 반응시켰다. 금속재료의 화학적/광물학적 변화를 알아보기 위해 주기적으로 용존 금속이온들의 농도를 측정하였으며, 실험이 종료된 이후 금속 시편 및 표면 이차생성물들을 전자현미경을 이용하여 분석하였다. 디설프리칸스가 없는 조건에서는 금속재료의 부식이 매우 미약하였으나, 미생물이 있는 경우에는 부식이 상대적으로 컸다. 관찰된 생지화학적 부식 산물은 주로 맥키나와이트와 황화구리 같은 검은색의 금속황화물이었으며, 표면에서 쉽게 분리되거나 콜로이드화되어 부유하였다. 특히, 구리 시편의 경우 용액 상에 용존 철이 존재할 때 세균에 의한 구리 부식의 가속화가 관찰되었는데, 이는 구리 표면에 다른 종의 황화철이 성장하면서 구리 간의 결속력을 약화시켰기 때문인 것으로 보인다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.163-168
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• 2006

동해의 해양 심층수 자원 기반 환경 연구의 일부로 청결기술을 적용하여 해수 중의 용존성 미량금속 (Cd, Co. Cu, Ni. Ph. Zn) 농도 분포와 변화를 조사하였다. 강원과 경북 지역에 총 6개 정점을 선정하고, 각 지역마다 최대 채수 수심 각각 200-300m 와 500m 까지 시료를 채취하였다. 본 연구의 미량금속을 위한 연안해수 표준물질 (CASS-4) 의 분석 결과 각 원소 평균 회수율은 Co의 89.4% 에서 Cd 의 99.8%의 범위였다. 용존 미량원소의 분포는 해역 및 시기적인 변화가 다양하게 나타났다 Cd, Ni, Zn의 경우는 영양염 의존형으로 표층에서 낮고 저층으로 갈수록 증가하는 경향이 뚜렷하였다. 그러나 Co, Cu, Ph 은 수직적으로 불규칙적인 분포를 나타내었다. 본 연구의 통해 심층수 원수의 중금속 농도는 해역별 수질 기준과 먹는 물 기준을 만족하였다.

• Ocean Science Journal
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• 제40권2호
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• pp.79-89
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• 2005

Laboratory radiotracer experiments were conducted to determine assimilation efficiencies (AE) from ingested algal food and oxic sediment particles, uptake rates from the dissolved phase, and the efflux rates of Cd, Cr and Zn in the Asiatic clam Corbicula fluminea. Among three elements, AE from both algal and sediment food was greatest for Cd, followed by Zn and Cr. The AEs of tested elements from algal food (Phaeodactylum tricornutum) were consistently higher than those from sediments at a given salinity and temperature. The influence of salinity (0, 4 and 8 psu) and temperature (5, 13 and $21^{\circ}C$) on the metal AEs was not evident for most tested elements, except Cd AEs from sediment. The rate constant of metal uptake from the dissolved phase $(k_u)$ was greatest for Cd, followed by Zn and Cr in freshwater media. However, in saline water, the $(k_u)$ of Zn were greater than those of Cd. The influx rate of all tested metals increased with temperature. The efflux rate constant was greatest for Cr $(0.02\;d^{-1})$, followed by Zn $(0.010{\sim}0.017\;d^{-1})$ and $Cd\;(0.006\;d^{-1})$. The efflux rate constant for Zn in clam tissues depurated in 0 psu $(0.017\;d^{-1})$ was faster than that in 8 psu $(0.010\;d^{-1})$. Overall results showed that the variation of salinity and temperature in estuarine systems can considerably influence the metal bioaccumulation potential in the estuarine clam C. fluminea. The relatively high Cd accumulation capacity of C. fluminea characterized by the high AE, high dissolved influx rate and low efflux rate, suggested that this clam species can be used as an efficient biomonitor for the Cd contamination in freshwater and estuarine environments.

• 해양환경안전학회지
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• 제13권1호
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• pp.1-7
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• 2007

동해의 해양 심층수 자원 기반 환경 연구의 일부로 청결기술을 적용하여 해수 중의 용존 미량금속(Cd, Co, Cu, Ni, Pb, Zn) 농도 분포와 변화를 조사하였다. 강원과 경북 지역에 총 6개 정점을 선정하고, 각 지역마다 최대 채수 수심 각각 200-300m와 500m까지 시료를 채취하였다. 본 연구의 미량금속을 위한 연안해수 표준물질(CASS-4)의 분석 결과 각 원소 평균 회수율은 Co의 89.4%에서 Cd의 99.8%의 범위였다. 용존 미량원소의 분포는 해역 및 시기적인 변화가 다양하게 나타났다. Cd, Ni, Zn의 경우는 영양염 의존형으로 표층에서 낮고 저층으로 갈수록 증가하는 경향이 뚜렷하였다. 그러나 Co, Cu, Pb은 수직적으로 불규칙적인 분포를 나타내었다. 본 연구의 동해 심층수 원수의 중금속 농도는 해역별 수질 기준과 먹는 물 기준을 만족하였다.

• 한국물환경학회지
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• 제16권4호
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• pp.421-430
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• 2000

To study the distribution and the behavior of trace metals in Kwangyang Bay, surface water samples were collected four times from August 1997 to May 1998 and were analyzed for trace metals (Cd, Co, Cu, Fe, Ni, Pb, Zn) by Atomic Absorption Spectrometer and Inductively Coupled Plasma Mass Spectrometer. Dissolved Co and Fe concentrations were comparatively high near the Seomjin River mouth. Particulate trace metal contents were relatively high near the Sueochun River mouth and near the Yeochun industrial complex. Distribution coefficients ($K_d$; $Lkg^1$) between dissolved and particulate phases of Fe, Pb, Co, Zn, Ni, Cu and Cd were $1.67{\times}10^8$, $1.37{\times}10^6$, $7.25{\times}10^5$, $4.43{\times}10^5$, $1.39{\times}10^5$, $9.1{\times}10^4$ and $1.8{\times}10^4$, respectively. In Kwangyang Bay, particulate trace-metal concentrations were as high as dissolved ones and showed seasonal and geographic variations.

• 자원리싸이클링
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• 제26권1호
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• pp.30-36
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• 2017

양극흙에 함유된 금과 은을 회수하기 위해 무기산(염산, 질산, 황산)과 thiourea 및 thiosulfate에 의한 침출실험을 수행했다. 산화제를 첨가하지 않은 조건에서 금은 무기산용액에 전혀 용해되지 않았다. 3종류의 무기산의 농도가 동일한 조건에서 황산용액에서 은의 침출율이 가장 높았으며, 염산의 농도가 증가함에 따라 $AgCl_2{^-}$의 형성에 따라 은의 침출율이 증가하였다. 한편 주석은 질산용액에 전혀 용해되지 않았으나, 구리, 니켈과 아연은 본 실험조건에서 모두 용해되었다. 황산과 thiourea의 혼합용액에서 금과 은은 모두 용해되었다. Thiosulfate용액에 은의 일부가 용해되었으나, 금은 전혀 용해되지 않았다.