• 자원ㆍ환경경제연구
• /
• 제17권3호
• /
• pp.31-59
• /
• 2008

본 연구는 한국과 미국의 수출입에 따른 산업별 독성물질(유해화학물질) 배출량 이전관계를 규명한 것이다. 분석에 이용된 자료는 한국과 미국에서 공동적으로 조사하는 51종의 독성물질 배출량과 2000년의 국제산업연관표이다. 분석결과, 한국의 경우, 총배출 강도가 높은 산업은 금속, 화학, 금속기계 등이며, 미국은 전자 및 가전, 화학, 플라스틱 및 고무 등에서 높은 배출강도를 나타내고 있다. 한국의 대(對)미국 수출구조는 미국의 대(對)한국 수출구조에 비해 자국의 환경에 불리한 측면을 가지고 있다. 즉, 미국의 대(對)한국 수출은 미국내 배출량 증가에 상대적으로 낮게 기여하고 있으나, 한국의 대(對)미국 수출은 한국내 배출량 증가에 상대적으로 크게 기여하고 있다.

• 대한환경공학회지
• /
• 제36권2호
• /
• pp.119-126
• /
• 2014

본 연구에서는 과불화합물(PFOA, PFOS)과 수계에 보편적으로 존재하는 중금속(Cu, Zn, Cr, Cd, Pb, Hg)의 복합독성을 Vibrio fischeri를 이용하여 평가하였다. PFOA와 PFOS의 경우, 30 min-$EC_{50}$값이 각각 134.21 (119.54-150.68)와 235.97 (180.96-307.70) mg/L로 PFOS 보다는 PFOA의 독성이 높은 것으로 나타났다. 한편 중금속류의 독성은 $Hg^{2+}$의 독성이 가장 높았으며, 이어서 $Pb^{2+}$, $Cr^{6+}$, $Cu^{2+}$, $Zn^{2+}$, $Cd^{2+}$ 순으로 높은 독성민감도를 나타냈다. 과불화합물류와 중금속류의 복합독성의 경우, PFOA와 PFOS 모두 $Cr^{6+}$과 공존할 시 상승효과가 나타났으며, PFOA + $Zn^{2+}$, PFOS + $Zn^2$, PFOA + $Cd^{2+}$, PFOS + $Cd^{2+}$의 조합은 상가 효과를 나타냈다. 이외의 복합물질은 모두 길항작용을 하는 것으로 확인되었다. 본 연구에서는 과불화합물인 PFOA, PFOS와 중금속 복합물질들의 조합에 따른 상호작용이 상이함을 확인하였고 이 결과로부터 과불화합물과 중금속 공존할 때 수환경에 야기할 수 있는 잠재적 위해성을 예측할 수 있다.

• Journal of Microbiology and Biotechnology
• /
• 제18권7호
• /
• pp.1298-1307
• /
• 2008

In this study, we investigated the inhibition effects of single and mixed heavy metal ions ($Zn^{2+},\;Ni^{2+},\;Cu^{2+},\;and\;Cd^{2+}$) on iron oxidation by Acidithiobacillus ferrooxidans. Effects of metals on the iron oxidation activity of A. ferrooxidans are categorized into four types of patterns according to its oxidation behavior. The results indicated that the inhibition effects of the metals on the iron oxidation activity were noncompetitive inhibitions. We proposed a reduced inhibition model, along with the reduced inhibition constant ($\alpha_i$), which was derived from the inhibition constant ($K_I$) of individual metals and represented the tolerance of a given inhibitor relative to that of a reference inhibitor. This model was used to evaluate the toxicity effect (inhibition effect) of metals on the iron oxidation activity of A. ferrooxidans. The model revealed that the iron oxidation behavior of the metals, regardless of metal systems (single, binary, ternary, or quaternary), is closely matched to that of any reference inhibitor at the same reduced inhibition concentration, $[I]_{reduced}$, which defines the ratio of the inhibitor concentration to the reduced inhibition constant. The model demonstrated that single metal systems and mixed metal systems with the same reduced inhibitor concentrations have similar toxic effects on microbial activity.

• 한국입자에어로졸학회지
• /
• 제9권3호
• /
• pp.173-185
• /
• 2013

Oxidations of metal generate large quantity of thermal and light energies but no toxic pollutants, so that metals with high calorific values, such as beryllium, boron, aluminum, magnesium, and lithium, are possible to be used as clean fuels instead of fossil fuels. However, they are so explosive due to very high oxidation rates that they should be stabilized by their surface passivation with oxides, organics and inorganics. For reasonable use of energetic metal particles as solid fuel, therefore, some detail information, such as thermal properties, preparation and passivation methods, and application area, of the energetic metals is introduced in this manuscript.

• Carbon letters
• /
• 제5권4호
• /
• pp.186-190
• /
• 2004

In this work, a nickel metal (Ni) electroplating on the activated carbon fiber (Ni/ACFs) surfaces was carried out to remove the toxic hydrogen chloride (HCl) gas. The surface properties of the treated ACFs were determined by using nitrogen adsorption isotherms at 77 K, SEM, and X-ray diffraction (XRD) measurements. HCl removal efficiency was confirmed by a gas-detecting tube technique. As a result, the nickel metal contents on the ACF surfaces were increased with increasing the plating time. And, it was found that the specific surface area or the micropore volume of the ACFs studied was slightly decreased as increasing the plating time. Whereas, it was revealed that the HCl removal efficiency containing nickel metal showed higher efficiency values than that of untreated ACFs. These results indicated that the presence of nickel metal on the ACF surfaces played an important role in improving the HCl removal over the Ni/ACFs, due to the catalytic reactions between nickel and chlorine.

• The Journal of Advanced Prosthodontics
• /
• 제6권2호
• /
• pp.138-145
• /
• 2014

Cobalt-Chromium (Co-Cr) alloys are classified as predominantly base-metal alloys and are widely known for their biomedical applications in the orthopedic and dental fields. In dentistry, Co-Cr alloys are commonly used for the fabrication of metallic frameworks of removable partial dentures and recently have been used as metallic substructures for the fabrication of porcelain-fused-to-metal restorations and implant frameworks. The increased worldwide interest in utilizing Co-Cr alloys for dental applications is related to their low cost and adequate physico-mechanical properties. Additionally, among base-metal alloys, Co-Cr alloys are used more frequently in many countries to replace Nickel-Chromium (Ni-Cr) alloys. This is mainly due to the increased concern regarding the toxic effects of Ni on the human body when alloys containing Ni are exposed to the oral cavity. This review article describes dental applications, metallurgical characterization, and physico-mechanical properties of Co-Cr alloys and also addresses their clinical and laboratory behavior in relation to those properties.

• Current Photovoltaic Research
• /
• 제3권4호
• /
• pp.126-129
• /
• 2015

Over the last two decades, quantum dot (QD) solar cells have attracted much attention due to the unique properties of QDs, including band gap tunability, slow hot electron cooling, and multiple exiton generation effect. However, most of the QDs employed in photovoltaic devices contain toxic heavy-metals such as cadmium or lead, which may limit the commercial application. Therefore, recently, heavy-metal-free QDs such as Cu-In-S or Cu-In-Se have been developed for application in solar cells. Here, we review the research trends in heavy-metal-free QD solar cells, mainly focusing on Cu-In-Se QD-sensitized solar cells (QDSC).

• 한국세라믹학회:학술대회논문집
• /
• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
• /
• pp.114.2-114.2
• /
• 2000

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2003년도 추계학술대회
• /
• pp.33-33
• /
• 2003

Organisms have evolved to use metal ions as cofactors for many proteins involved in critical biological processes. However, these metals are highly toxic when present in excess or if released in its free reactive form, and environmental contamination by non-physiological metals has been a concern for public health.(omitted)

• The Korean Journal of Ecology
• /
• 제19권6호
• /
• pp.519-527
• /
• 1996

To examine the possibility of biomonitoring of heavy metal removal ability and soil, a study was performed to investigate the heavy metal removal ability and metal-binding protein (MBP) as detoxification process using Oenanthe stolonifera. After O. stolonifera was exposed to individuals (cadmium, zinc) and mixture (cadmium+zinc)for 4 days, removal rate of heavy metal and pH in the treatment medium was measured. MBP was assayed by means of ion exchange column chromatography. The exposure to mixture (Cd:76.8%, Zn:75%) rather than individuals (Cd:82.9%, Zn:90.4%) showed a synergism raising the toxic effect. Initial removal rate was different for each heavy metal : in case of exposure to cadmium it was over 60% on day 1, while for zinc it was 75~90% on day 4. Throughout the experimental period, pH value of treatment medium continuously decreased, since cortex in the roots may secret organic acid to adjust and prevent toxicity of metals. The existence or MBP in the 70~80 fraction and the presence of Zn-enzyme pool was ascertained with the column chromatography. This study demonstrated a possibility that heavy utilized as a biomarker of heavy metal pollution.