• Journal of the Korean GEO-environmental Society
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• v.11 no.11
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• pp.63-75
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• 2010

There are several remediation technologies for heavy metal contaminated soils but increasing cost limits the application of the technology if the contaminated area is large. Therefore, stabilization, which blocks the release of heavy metals or makes slow the release, is one of the applicable technology for the heavy metal contaminated soil. Current study is an applicability test for a smelter area with various stabilizer such as magnetite, hematite, zeolite-A, zeolite-X, zeolite-Y, zinc oxide, calcium oxide, carbon trioxide, manganese oxide, manganese dioxide, fish bone, sodium phosphate. The soil contaminated with arsenic, lead, copper, nickel, and zinc could not be stabilized only one stabilizer which is known to have stability for certain metal. Many of the stabilizer works for a few metal but not all of the heavy metal. In several cases, stabilizers increase the release of the other metals while they stabilize some metals. In general, the stabilizing efficiency was increased with time. For Ni, Pb, calcium oxide, carbon trioxide, manganese oxide had good stabilizing effect in water extractable portion. For Cu, manganese oxide, zeolite showed good results especially in the exchangeable portion of the sequential extraction. For As, magnetite had good ability but most of the metal oxide which showed good result for other heavy metals increased with the release of As. Current study suggest that multiple stabilizers are needed for the contaminated soil and dose of the stabilizer and stabilizing time should be carefully considered for the soil contaminated with various metals.

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.193-199
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• 2006

The catalytic oxidation of toluene over $-Al_2O_3$ supported copper-manganese oxide catalysts in the temperature range of $160-280^{\circ}C$ was investigated by employing a fixed bed flow reactor. The catalysts were characterized by BET, scanning electron microscopy (SEM), temperature-programmed reduction(TPR), temperature-programmed oxidation(TPO), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction(XRD) techniques. Catalytic oxidation of toluene was achieved at the below $280^{\circ}C$, and the optimal content of copper and manganese in the catalyst was found to be 15.0 wt％Cu-10.0 wt％Mn. From the TPR/TPO and XPS results, the redox peak of 15 Cu-10 Mn catalyst shifted to the lower temperature, and the binding energy was shifted to the higher binding energy. Furthermore, It is considered that $Cu_{1.5}Mn_{1.5}O_4$ is superior to Mn oxides and CuO in the role as active factor of catalysts from the XRD results and also catalytic activities are dependent on the redox ability and high oxidation state of catalysts.

• Journal of Environmental Science International
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• v.19 no.6
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• pp.715-735
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• 2010

This study is designed to assess the priority order of the chemicals to cause to generate occupational diseases in order to understand the fundamental data required for the preparation of health protective measure for the workers dealing with chemicals. The 41 types of 51 ones of chemicals to cause to generate the national occupational diseases were selected as the study objects by understanding their domestic use or not, and their occupational diseases' occurrence or not among 110,608 types of domestic and overseas chemicals. To assess their priority order the sum of scores was acquired by understanding the actually classified condition based on a perfect score of physical riskiness(90points) and health toxicity(92points) as a classification standard by GHS, the priority order on GHS riskiness assessment, GHS toxicity assessment, GHS toxic xriskiness assessment(sum of riskiness plus toxicity) was assessed by multiplying each result by each weight of occupational disease's occurrence. The high ranking 5 items of chemicals for GHS riskiness assessment were turned out to be urethane, copper, chlorine, manganese, and thiomersal by order. Besides as a result of GHS toxicity assessment the top fives were assessed to be aluminum, iron oxide, manganese, copper, and cadium(Metal) by order. On the other hand, GHS toxicity riskiness assessment showed that the top fives were assessed to be copper, urethane, iron oxide, chlorine and phenanthrene by order. As there is no material or many uncertain details for physical riskiness or health toxicity by GHS classification though such materials caused to generate the national occupational diseases, it is very urgent to prepare its countermeasure based on the forementioned in order to protect the workers handling or being exposed to chemicals from health.

• Resources Recycling
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• v.21 no.5
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• pp.3-17
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• 2012

Selective leaching processes for copper, gold, nickel, and cobalt have been investigated because there is an advantage of ammoniacal hydrometallurgy that metal such as copper could be selectively extracted restricting the dissolution of iron or calcium. In the present article, the studies for selective ammoniacal leaching of copper from motor scraps and waste printed circuit boards (PCBs), for ammoniacal leaching of gold to decrease the amount of cyanide used or to substitute cyanide by thiosulfate, and for ammoniacal leaching to recover nickel and cobalt from nickel oxide ore and intermidiate obtained from manganese nodule treatment process were summarized and further studies were proposed for domestic technology development for ammoniacal hydrometallurgy processes.

• Journal of Preventive Medicine and Public Health
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• v.31 no.3 s.62
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• pp.414-423
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• 1998

Metal fume fever has been known as an occupational disease is induced by intense inhalation of fresh metal fume with a particle size smaller than $0.5{\mu}m\;to\;1{\mu}m$. The fumes originate from heating metals beyond their boiling point, as happens, for example, in welding operations. Oxidation usually accompanies this process. In most cases, this syndrome is due to exposure to zinc oxide fumes; however, other metals like copper, magnesium, cadmium, manganese, and antimony are also reported to produce such reactions. Authors report a case of metal fume fever suspected to be associated with copper fume inhalation. The patient was a 42-year-old male and was a smoker. He conducted inert gas tungsten arc welding on copper-coated materials without safety precautions such as a protective mask and adequate ventilation. Immediately after work, he felt metallic taste in his mouth. A few hours after welding, he developed headache, chilling sensation, and chest discomfort. He also complained of myalgia, arthralgia, feverish sensation, thirst, and general weakness. Symptoms worsened after repeated copper welding on the next day and subsided gradually following two weeks. Laboratory examination showed a transient increase of neutrophil count, eosinophilia, elevated erythrocyte sedimentation rate, and positive C-reactive proteinemia. Blood and urine copper level was also increased compared to his wife. Before this episode, he experienced above complaints several times after welding with copper materials but welding of other metals did not produce any symptoms. It was suggested that copper fume would have induced metal fume fever in this case. Further investigations are needed to clarify their pathogenic mechanisms.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.3
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• pp.249-256
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• 2006

Catalytic combustion of toluene was investigated on the Cu-Mn oxide catalysts prepared by the impregnation(Imp) and the deposition-precipitation(DP) methods. The mixing of copper and manganese has been found to enhance the activity of catalysts. It is then found that catalytic efficiency of the Cu-Mn oxide catalyst prepared by the DP method on combustion of toluene is much higher than that of the Cu-Mn oxide catalyst prepared by Imp method with the same chemical composition. The catalyst prepared by the deposition-precipitation method observed no change of toluene conversion at time on stream during 10 days and at the addition of water vapor. On the basis of catalyst characterization data, it has been suggested that the catalysts prepared by the DP method showed uniform distribution and smaller particle size on the surface of catalyst and then enhanced reduction capability of catalysts. Therefore, we think that the DP method leads on progressive capacity of catalyst and promotes stability of catalyst. It was also presumed that catalytic conversion of toluene on the Cu-Mn oxide catalyst depends on redox reaction and $Cu_{1.5}Mn_{1.5}O_4$ spinel phase acts as the major active sites of catalyst.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.129-135
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• 2016

CO oxidation was performed with Cu-Mn and Cu-Zn co-precipitated catalysts as differential precipitant, metal ratio and calcination temperature. The effects of differential metal mole ratio and calcination temperature in mixed metal oxide catalyst were investigated with CO oxidation reaction. Physiochemical properties were studied by XRD, $N_2$ sorption and SEM. 2Cu-1Mn with $Na_2CO_3$ catalyst calcined at $270^{\circ}C$ has a large surface area $43m^2/g$ and the best activity for CO oxidation. $Cu_{0.5}Mn_{2.5}O_4$ in XRD peak shows the lower activity than others. The catalytic activity over the catalyst calcined $270^{\circ}C$ displayed the highest conversion, and it was better activity comparing with Pt catalysts CO conversion.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2349-2356
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• 2014

The recycling technology by the catalytic conversion is one of the most promising techniques for the $CO_2$ treatment of coal burning power plant flue gases. The conversion of $CO_2$ to valuable product of $CH_4$ can be used as a fuel to run the turbine for electricity generation. Through this technique, the amount of coal needed for the combustion in a gas turbine can be reduced as well as $CO_2$ emissions. Therefore, a series of catalysts based on cerium oxide doped with copper, nickel and manganese were prepared by impregnation method. From the characterization analysis, it showed that the prepared catalysts calcined at $400^{\circ}C$ were amorphous in structure with small particle size in the range below 100 nm. Meanwhile, the catalyst particles were aggregated and agglomerated with higher surface area of $286.70m^2g^{-1}$. By increasing the calcination temperature of catalysts to $1000^{\circ}C$, the particle sizes were getting bigger (> 100 nm) and having moderate crystallinity with lower surface area ($67.90m^2g^{-1}$). From the catalytic testing among all the prepared catalysts, Mn/Ce-75/$Al_2O_3$ calcined at $400^{\circ}C$ was assigned as the most potential catalyst which gave 49.05% and 56.79% $CO_2$ conversion at reaction temperature of $100^{\circ}C$ and $200^{\circ}C$, respectively.

• Economic and Environmental Geology
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• v.41 no.6
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• pp.773-795
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• 2008

The major import minerals of South Korea are copper ore, lead-zinc ore, iron ore, manganese ore and molybdenum ore. Oversea resources development of South Korea have 92 projects in 14 nations of Asia, 29 projects in 10 nations of America and Europe, and 14 projects in 9 nations of Middle Asia and Africa. But, most projects of them are found in Australia, China, Mongolia and Indonesia. The most projects of the Australia, China and Indonesia are interested in coal and a little projects of them have manganese, iron, lead-zinc, nickel, copper, gold, molybdenum, rare earth elements and uranium. The most projects of the Mongolia are interested in gold and rare earth elements. Representative ore deposits models of metal resources are Orogenic lode deposits, Volcanogenic massive sulphide deposits, Porphyry deposits, Sedimentary exhalative deposits, Mississippi valley type deposits, Iron oxide copper-gold deposits and Magmatic nickel-copper-platinum group element deposits based on global distribution, reverses and grades of their deposits models. If oversea mineral resources will be examined the mineral reserves, mineral mine production and ore deposits models of nations and then survey and investigate of mineral resources, we may be maintained ore body of high grade at survey area and decrease the investment risk.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.175.2-175.2
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• 2014

Graphene (G) has been modified with palladium, copper, and manganese oxide nanoparticles (NPs), and their catalytic applications have been studied in C-C coupling reactions and methylmercaptan (CH3SH) decomposition reactions. In this research, graphite oxide (GO) sheets were exfoliated and oxidized from graphite powder and impregnated with metal precursors including Pd2+, Cu2+, and Mn2+. The thermal treatments of the metal impregnated GO in preferred gas environments produced Pd NPs on graphene (Pd/G), PdO NPs on GO (PdO/GO), and CuOx and MnOx NPs on graphene (CuOx/MnOx/G). In case of Pd/G and PdO/GO, the TEM images show that, although the mean size of the Pd NPs changed significantly before and after the C-C coupling reaction, that of the PdO NPs didn't, implying that the PdO/GO was superior to Pd/G in terms of the recyclability. Also, we demonstrate that the CuOx/MnOx/G exerts the excellent catalytic efficiency in CH3SH decomposition reaction comparing with conventional catalysts. The chemical and electronic structural changes were investigated using XRD and XPS.