• Journal of Soil and Groundwater Environment
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• v.21 no.3
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• pp.58-63
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• 2016

The study examined the level of heavy metal contamination by dividing military rifle shooting ranges into the three areas, i.e firing, trajectory, and target. The target area was found to be contaminated at a level higher (Cu 845 mg/kg, Pb 30,487 mg/kg) than the Worrisome Level of Soil Contamination (hereinafter referred to as the “Worrisome Level”) The trajectory area was predicted to be free from contamination, but it did indicate contamination although it was pretty much lower (Cu 23 mg/kg, Pb 99 mg/kg) than Worrisome Level. This is attributed to the contamination spread when rearranging the soil of the target area during the maintenance of the shooting range. The firing area was also predicted to be free from heavy metal contamination, but the results analyzed indicated a contamination higher (Cu 201 mg/kg, Pb 2,286 mg/kg) than Worrisome Level. This is attributed to the fragments of the broken bullet scattering due to the pressure generated as the bullet leaves the muzzle. An examination of heavy metal contamination in the discharge area as well as gutters to prevent the intrusion of rain water from perimeter revealed a high level of contamination (Cu 298 mg/kg, Pb 6,497 mg/kg), which makes it necessary to take measures.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.4
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• pp.23-29
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• 2000

We demonstrate the fabrication method of high-density and high-quality solder bump solving a copper (Cu) cross-contamination in Si-LSI laboratory. The Cu cross-contamination is solved by separating solder-bump process by two steps. Former is via-formation process excluding Cu/Ti under ball metallurgy (UBM) layer sputtering in Si-LSI laboratory. Latter is electroplating process including Ti-adhesion and Cu-seed layers sputtering out of Si-LSI laboratory. Thick photoresist (PR) is achieved by a multiple coating method. After TiW/Al-electrode sputtering for electroplating and via formation in Si-LSI laboratory, Cu/Ti UBM layer is sputtered on sample. The Cu-seed layer on the PR is etched during Cu-electroplating with low-electroplating rate due to a difference in resistance of UBM layer between via bottom and PR. Therefore Cu-buffer layer can be electroplated selectively at the via bottom. After etching the Ti-adhesion layer on the PR, Sn/Pb solder layer with a composition of 60/40 is electroplated using a tin-lead electroplating bath with a metal stoichiometry of 60/40 (weight percent ratio). Scanning electron microscope image shows that the fabricated solder bump is high-uniformity and high-quality as well as symmetric mushroom shape. The solder bumps with even 40/60 $\mu\textrm{m}$ in diameter/pitch do not touch during electroplating and reflow procedures. The solder-bump process of high-uniformity and high-density with the Cu cross-contamination free in Si-LSI laboratory will be effective for electronic microwave application.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.10a
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• pp.57-60
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• 1999

Geochemical study was carried out to find out soil contamination at the heaped soil, moved from bottom of the storage pond in Pohang industrial complex, in Moondug, Chemical analysis showed that contents of heavy metals in the soil were higher than those of the ordinary soil. Contents of Cu and Cd in the soil exceeded Korean standard of soil contamination. Especially content of Cu exceeded Korean standard of soil contamination(50ppm) at the six points and at one point content of Cu was 113.3ppm. Contents of Be were so higher than U.S RCRA standard(0.2ppm) that they can affect soil environment. The followed research about relation between pollutant and soil and proper measures are required to prevent soil contamination from affecting environment of Moondug.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2227-2232
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• 2011

The new metrology, Advanced Poly-silicon Ultra-Trace Profiling (APUTP), was developed for measuring bulk Cu and Ni in heavily boron-doped silicon wafers. A Ni recovery yield of 98.8% and a Cu recovery yield of 96.0% were achieved by optimizing the vapor phase etching and the wafer surface scanning conditions, following capture of Cu and Ni by the poly-silicon layer. A lower limit of detection (LOD) than previous techniques could be achieved using the mixture vapor etching method. This method can be used to indicate the amount of Cu and Ni resulting from bulk contamination in heavily boron-doped silicon wafers during wafer manufacturing. It was found that a higher degree of bulk Ni contamination arose during alkaline etching of heavily boron-doped silicon wafers compared with lightly boron-doped silicon wafers. In addition, it was proven that bulk Cu contamination was easily introduced in the heavily boron-doped silicon wafer by polishing the wafer with a slurry containing Cu in the presence of amine additives.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.3
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• pp.195-206
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• 2014

In this study, soil contamination maps related to Cu and Pb were created at the Busan abandoned mine in Korea using a handheld X-Ray Fluorescence(XRF) and Geographic Information Systems(GIS). Hydrological analysis was performed using the Digital Elevation Model(DEM) of the study area to identify the flow directions of surface runoff where pollutants can be dispersed from the soil contamination sources. 24 locations for measuring the soil contamination related to Cu and Pb were selected by considering the result of hydrological analysis. The results measured at the 24 locations using the handheld XRF showed that the highest value of Cu contamination is 8,255ppm and that of Pb is 2,146ppm. The field investigation data were entered into ArcGIS software, and then soil contamination maps regarding Cu and Pb with a 5m grid-spacing were created after performing spatial interpolations using the ordinary kriging method. As a result, we could know that high concentrations of Cu and Pb are presented at the waste and tailings dumps around the abandoned mine openings. This study also showed that the handheld XRF and GIS can be utilized to create soil contamination maps related to Cu and Pb in the field.

• Journal of Applied Biological Chemistry
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• v.59 no.1
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• pp.83-90
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• 2016

The aim of the present study was to evaluate the degree of metal contamination of the Turag River water and its suitability for irrigation. Twenty water samples were analyzed for physicochemical parameters and metals viz., calcium, magnesium, potassium (K), sodium, copper (Cu), zinc (Zn), iron (Fe), manganese (Mn), lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni). All water samples were slightly alkaline to alkaline. Regarding electrical conductivity (EC), all samples were suitable for crop in soils with moderate permeability and leaching. Water samples were medium salinity and low alkalinity hazard classes. In terms of total dissolved solids (TDS), all samples were classified as freshwater. As per sodium adsorption ratio (SAR) and soluble sodium percentage (SSP), all samples were classified as excellent. No residual sodium carbonate (RSC) was detected in any of the samples, indicating suitability for irrigation; and all samples were considered very hard. Cr and Mn contents in all samples were above FAO guideline values and, therefore, these metals were considered toxic. Zn, Cu, Pb, Cd, and Ni concentrations were below acceptable limit for irrigation and do not pose a threat to soil environment. Significant relationships were found between EC and TDS, SAR and SSP, SAR and RSC, and SSP and RSC. The combinations of ions such as K-Zn, K-Fe, K-Cu, K-Mn, K-Pb, Zn-Fe, Zn-Cu, Zn-Mn, Fe-Mn, Cu-Mn, Cu-Pb and Mn-Pb exhibited significant correlation. This study revealed that Turag River water samples are contaminated with Cr and Mn. This fact should not be ignored because water contamination by metals may pose a threat to human health through food chain.

• Economic and Environmental Geology
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• v.29 no.3
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• pp.305-313
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• 1996

In order to investigate the extent and degree of Cd, Cu, Pb and Zn contamination affected by mining activities of the Dalsung Cu~W mine, sampling of stream sediments and waters has been undertaken up to 1.5 km downstream from the mine at 50~150 meter intervals. Analysis of the samples was carried out using ICP-AES for Cd, Cu, Pb and Zn. Physical and chemical properties of sediments (pH, organic matter contents, cation exchange capacity) and waters (pH, Eh and temperature) were also measured. The properties of the sediment samples were characterized by low pH (3.0~5.5), low organic matter contents (2~5%) and a moderate degree of cation exchange capacity (7~15 meq/100 g) with a high proportion of sand fraction. The pH values of water samples ranged from 3.0 to 5.0 and the Eh levels were in the range of 350~530 mV. Concentrations of Cd, Cu, Pb and Zn in the sediments averaged 3.2 mg/kg, 1,390 mg/kg, 451 mg/kg and 262 mg/kg with the range of 0.6~11.4 mg/kg, 15~3,800 mg/kg, 14~1,330 mg/kg and 63~1,060 mg/kg, respectively. Significant levels of the heavy metals were also found in the water samples with the range of $10{\sim}170{\mu}gCd/l$, $300{\sim}41,600{\mu}gCu/l$, $10{\sim}80{\mu}gPb/l$ and $700{\sim}15,400{\mu}gZn/l$. These elevated concentrations in the sediments and waters may be caused by the weathering of mine waste materials and their high solubilities under acidic and/or oxidizing conditions. Although metal concentrations in the samples decrease with the distance from the mine, heavy metal contamination of sediments and waters were also found at the 1.5 km downstream due to the mobile conditions of the heavy metals, with particular reference to Cd and Zn in stream waters.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.4
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• pp.302-313
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• 2012

Concentrations of selected heavy metals (Al, Fe, Mn, Cr, Cu, Ni, Zn, Pb, As and Cd) in surface sediments from 96 sites in Masan and Jinhae Bay were studied in order to understand metal contamination. Results show that the surface sediments were mainly enriched by Cu (18-294 ppm), Zn (67-568 ppm), Pb (10-120 ppm) and Cd (0.2-3.5 ppm). The coastal zone of Masan Bay was significantly more contaminated than the non-coastal zone, and spatial distribution pattern suggested additional sources of heavy metal input in the coastal area. The enrichment ratio and geoaccumulation index ($I_{geo}$) have been calculated and the relative contamination levels assessed in the study area. The enrichment ratios of Cu, Zn, Pb and Cd in Masan Bay have been observed to be relatively high. $I_{geo}$ results reveal that the study area is not contaminated with respect to Fe, Mn, Cr and Ni; moderately to strongly contaminated with Cu, Zn and Pb; and strongly to strong contaminated with Cd. The high contents of Cu, Zn, Pb and Cd in the study area result from anthropogenic activities in the catchment area. Based on the eight different sediment quality guideline values from USA (ERL, ERM), Canada (TEL, PEL), Australia/New Zealand (ISQG-high, ISQG-low) and Hong Kong (ISQV-low, ISQV-high), sediment quality of Masan and Jinhae Bay was also assessed and characterized.

• Journal of the Korean Society for Marine Environment & Energy
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• v.1 no.1
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• pp.83-92
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• 1998

Heavy metals concentration in superficial sediment of effluent discharging area was rapidly increased by annual loadings of Zn(8.465 Kg), Ni(3,291 Kg), Cu(1,636 Kg) and Pb(1,250 Kg) from sewage effluent of 63×10/sup 6/ m³/yr. In a consequent result, specially the concentrations of Zn and Cu in the sediment were three times higher than preindustrial reference values. The evaluation by multiple ecological risk indices showed that heavy metals contamination in sediment of discharging area was 'heavily Polluted level' by sediment quality criteria and increased 2.6 times by the degree of contamination. It was also judged that toxicological effects of sediment receiving the primary effluent would occasionally (16～47%) occur by guidelines for adverse biological effect.

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.6.1-6.10
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• 2016

Objectives This study examined the spatial distribution and the extent of soil contamination by heavy metals resulting from primitive, unconventional informal electronic waste recycling in the Agbogbloshie e-waste processing site (AEPS) in Ghana. Methods A total of 132 samples were collected at 100 m intervals, with a handheld global position system used in taking the location data of the soil sample points. Observing all procedural and quality assurance measures, the samples were analyzed for barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn), using X-ray fluorescence. Using environmental risk indices of contamination factor and degree of contamination ($C_{deg}$), we analyzed the individual contribution of each heavy metal contamination and the overall $C_{deg}$. We further used geostatistical techniques of spatial autocorrelation and variability to examine spatial distribution and extent of heavy metal contamination. Results Results from soil analysis showed that heavy metal concentrations were significantly higher than the Canadian Environmental Protection Agency and Dutch environmental standards. In an increasing order, Pb>Cd>Hg>Cu>Zn>Cr>Co>Ba>Ni contributed significantly to the overall $C_{deg}$. Contamination was highest in the main working areas of burning and dismantling sites, indicating the influence of recycling activities. Geostatistical analysis also revealed that heavy metal contamination spreads beyond the main working areas to residential, recreational, farming, and commercial areas. Conclusions Our results show that the studied heavy metals are ubiquitous within AEPS and the significantly high concentration of these metals reflect the contamination factor and $C_{deg}$, indicating soil contamination in AEPS with the nine heavy metals studied.