• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.77-88
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• 1994

This experiment was carried out to investigate the effect of sewage sludge compost amended soils on the growth and accumulation patterns of heavy metals in plant parts of Orchardgrass seedlings, changes in physical properties and chemical composition, and heavy metal residue in soils. Mixture ratios of sewage sludge compost and soil(loam) were 100:0, 80:20, 60:40, 40:60, 20:80 and 0:100(control), respectively. The results obtained were as follows; 1. The physical properties and chemical compostion of soils were improved by increase in mixture ratios of sewage sludge compost. 2. The biological yield of Orchardgrass seedlings was increased with mixture ratios of sewage sludge compost. 3. The dry weight of shoot(SH) was increased with both of yield components(NT and WT) and biological yield of Orchardgrass seedlings. 4. The total nitrogen concentrations(TN) of plants was increased with quadratically up to the biological yield of 100% mixture ratio of sewage sludge compost. 5. Lead(Pb) concentration of soil in over the 60% mixture ratios of sewage sludge compost were in excess of limiting level(50ppm) of organic fertilizers.

• Korean Journal of Veterinary Service
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• v.29 no.4
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• pp.459-467
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• 2006

This study was designed to investigate if there were groundwater contamination in 17 landfill where slaughtered animals were buried during the crisis of 2002 foot-and-mouth-disease (FMD) outbreaks in Gyeonggi province. From March to August 2005 groundwater was collected once a month from 17 sites, and examined with potential for hydrogen (pH), colour, turbidity, lead (Pb), arsenic (As), mercury (Hg), cadmium (Cd), copper (Cu), zinc (Zn) , iron (Fe), manganese (Mn) , aluminium (Al), nitrate-nitrogen $(NO_3-N)$, ammonia-nitrogen $(NH_3-N)$, microbial pathogen and Escherichia spp. In the examination of $NH_3-N$ which of the mean concentration was from not-detected (ND) to 0.05 mg/l. The range of $NH_3-N$ level was $0.3-24.1mg/{\ell}$. However, groundwater from four sites was to go beyond the drinking water quality standard (DWQS), i.e., the mean concentration of those were $15.5mg/{\ell}\;(site\;1),\;20.7mg/{\ell}\;(site\;9),\;24.1mg/{\ell}\;(site\;13)\;and\;10.6mg/{\ell}\;(site\;17)$. In the investigation of pH, colour and turbidity, all of the pH were below of DWQS (pH 5.8-6.6), but one site in color test and four sites in turbidity test were over the standard level. Among 9 metal ions examined, Mn was in excess of DWQS, and its concentration was $2.4mg/{\ell}$. Pb, Cd, Hg and As were not traced. The contents of Cu, Zn, Fe and Al were $ND-0.22mg/{\ell},\;0.01-0.05mg/{\ell},\;ND-0.05mg/{\ell}\;and\;0.03-0.16mg/{\ell}$, respectively. Escherichiae spp were not identified, but bacterial colonies were detected at 3 groundwater including 2 sites over the DWQS at the level of $491CFU/m{\ell}\;(site\;4)\;and\;217CFU/m{\ell}\;(site\;15)$.

• Economic and Environmental Geology
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• v.9 no.3
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• pp.143-156
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• 1976

The Cretaceous metal ore deposits in the Gyeongsang basin of Gyeongsangbuk-do are characterized by the formation of metallogenic provinces which show zonal distribution pattern around Yeonil province where pneumatolytic type is dominated and hydrothermal type are distributed in the order of decreasing temperature type outward. Some Cretaceous granitic rocks include zoned alkali feldspars which reflect rapid variation of $H_2O$ during emplacement and crystallization of the water-saturated granitic magma. The ore deposits are considered to be originated from upward transportation of ore solution from the excess of water exhausted from uprising magma, which seems to be intimately related to the fact that the majority of the ore deposits in Daegu area are cummulated around the granites including zoned alkali feldspars. In order to collect geochemical data necessary for geochemical exploration in the study area, certain trace elements were chosen as pathfinders from monzonite and soil in the vicinity of Dalsung Tungsten Mine by studying the dispersion patterns of trace elements: Ba and Sr show trends to decrease toward ore deposit while Cu, Pb, and Mo increase. Around mining area there are distributed apparently Equisetum arvense Linne and Mentha sachinensis Kudo which may be used as index plants. In the viewpoint of geologic structure, the trends of the ore veins in contact aureole around the Palgongsan granite body correspond with the pre- and syn- plutonism joint pattern in hornfels in the area.

• Journal of the Korean Ceramic Society
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• v.33 no.10
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• pp.1101-1108
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• 1996

No-doped PZT thin films have been fabricated on Pt/Ti/SiO2/Si substrate using Sol-Gel technique. A fast annealing metho (three times of intermediate and final annealing) was used for the preparation of multi-coated 1800$\AA$ thick Nb-doped PZT thin films. As Nb doping percent was increased leakage current was lowered approximately 2 order but dielectic properties were degraded due to the appearance of pyrochlore phase and domain pinning. Futhermore the increase of the final annealing temperature up to 74$0^{\circ}C$lowered the pyrochlore phase content resulting in enhancing the dielectric properties of the Nb doped films. The 3%-Nb doped PZT thin films with 5% excess Pb showed a capacitance density of 24.04 fF/${\mu}{\textrm}{m}$2 a dielectric loss of 0.13 a switchable polarization of 15.84 $\mu$C/cm2 and a coercive field of 32.7 kV/cm respectively. The leakage current density of the film was as low as 1.47$\times$10-7 A/cm2 at the applied voltage of 1.5 V.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.469.2-469.2
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• 2014

All-solid-state solar cell based on Chloride doped organometallic halide perovskite, (CH3NH3)PbIxCl3-x, has achieved a highly power conversion efficiency (PCE) to over 15% [1] and further improvements are expected up to 20% [2]. In this way, solar cells using novel light absorbing perovskite material are actively being studied as a next generation solar cells. However, making solution-process require high temperature up to $500^{\circ}C$ to form compact hole blocking layer and sinter the mesoporous oxide scaffold layer. Because of this high temperature process, fabrication of flexible solar cells on plastic substrate is still troubleshooting. In this study, we fabricated highly efficient flexible perovskite solar cells with PCE in excess of 11%. Atomic layer deposition (ALD) is used to deposit dense $TiO_2$ as hole blocking layer on ITO/PEN substrate. The all fabrication process is done at low temperature below $150^{\circ}C$. This work shows that one of the important blueprint for commercial use of perovskite solar cells.

• Journal of the korean society of oceanography
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• v.31 no.2
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• pp.43-54
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• 1996

Jinhae Bay, one of the largest tidal bays on the southern coast of Korea, is an area with thick accumulations of recent, fine-grained sediments, mainly supplied from the Nakdong River. The preponderance of silt and clay particles reflects the large quantity of sediments transported in suspension. Although the clay mineral assemblage is similar to that derived from the nearby Nakdong River, relatively high concentration (3-9%) of smectite suggests some local input of fine particles from several streams around the bay or some contribution from the offshore water that may be influenced by the Tsushima Current. The content of organic matters in sediments is as high as 12%, and their C/N ratios imply that they are comprised of mixtures derived from marine plankton and terrestrial plants. $^{210}Pb$ excess activity profiles of sediment cores yield an average sedimentation rate (a 100-year time scale) of about 2-5 mm/yr, which coincides well with the long-term sedimentation rate (a 1000-year time scale) estimated from the sediment isopach map. On the basis of sediment bulk density and sedimentation rate, an annual sink of mud in the bay is estimated approximately 1.0 ${\times}$ $10^{6}$ tons per year.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.333-338
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• 2016

The purpose of this study was to understand the pollution level of the surface sediment of Sihwa Lake by assessing its geochemical characteristics and investigating the spatial distribution of trace metals and organic matter. In the surface sediment of Sihwa lake, the mean grain size was between 2.94 and 6.35 Ø and the main type of sediment was sandy silt. The concentrations of As, Co, Cr, Ni, V and Li among the metal elements in the surface sediment were correlated with the mean crust concentration (p<0.05). Based on the strong correlation between the metals (Cd, Cu, Pb and Zn) and organic matter (Ignition Loss), the concentrations of these metal elements seem to be controlled by the organic matter dilution effect. The trace metal pollution level, determined by applying the Republic of Korea Marine environmental standard and the US National Oceanic and Atmospheric Administration's sediment quality guidelines, showed the pollution level of As to be either close to or in excess of the above-mentioned standards at almost all levels. The enrichment factor and geoaccumulation index of As showed that there was an incremental increase of pollution by elements other than V, Cr, Co, Fe, Al and Mn. Moreover, the nearby industrial area and dike were more polluted than the other areas, so the surface sediments in Sihwa lake should be monitored by taking into consideration the geological variations.

• Korean Journal of Community Nutrition
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• v.7 no.6
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• pp.833-843
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• 2002

This study was carried out to investigate the effect of hygiene education on the microbiological changes of processing utensils and the environmental in the manufacture of cereals and to evaluate the Cd, Pb contents and nutrient compositions of 11 cereals. The result of microbiological evaluation was that fungi, coliforms and staphylococcus species were detected in employees, on equipment, utensils and environments in the first inspection. Fungi were detected in most of the cereals, staphylococcus species were detected in soybeans, perilla seeds and sea tangle How, and bacillus cereus was detected in sorghum and black sesame seeds. The water content of rice, barley, glutinous rice, brown rice and carrot flour in packaged products, and in carrot flour, angelica keiskei, carrot, sea mustard and potato in bulk products was in excess of 8.0%. The Pb content of cereals was 0.14-0.51 mg/kg and Cd was not found. The acid value of Job s tears flour and black sesame seed flour was higher than 5.0 mg/g oil. Cereals were manufactured from 41 different cereals and grains, legumes, seeds and nuts, vegetables, potatoes, seaweeds, fruits, glucose and salt. The average content of cereals and grains, legumes, and seeds and nuts in cereals was 75.75%, 16.19% and 4.93%, respectively. The mean nutrient content per 100 g of cereals was calories 365.8kcal, protein 13.3 g, fats 5.9 g, carbohydrates 63.4 g, Ca 91.8 mg, p 269.9 mg, Fe 3.15 mg, Na 76.2 g, K 421.8 mg, Zn 2.33 mg, Vit. A 12.5 R.E., Vit. B$_1$0.23 mg, Vit. $B_2$ 0.16 mg, Vit. $B_6$ 0.46 mg, Niacin 3.5 mg, Vit. C 1.36 mg, folic acid 62.3 $\mu$g and Vit. E 1.24 mg. When nutrients value of 48 g of cereals and 200 $m\ell$l of milk was compared to 1/3 of the RDA, the values were below than 60% of 1/3 of the RDA except Na, K, Vitamin $B_1$ and C contents. The average carbohydrate : protein : fat ratio of energy intake was 54.27 : 17.45 : 28.28, respectively. Therefore, a training program consisting of the education of the staff in surveillance and standard operating procedures, the elimination of dangerous procedures, sanitation checklist, the implementation of Preparation methods and standard recipes for cereals is required.

• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.83-90
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• 2010

This study was conducted to investigate the residue amount of harmful materials on the 153 commercial medical herbs in Gwangju area. It was performed using the GC-ECD, GC-NPD, GC-MSD and the LC-UVD, LC-FLD, LC-MSD to analyze 200 pesticides. The heavy metals were determined using a Mercury analyzer and AAS. The sulfur dioxides were analyzed by modified Monnier-Williams method. The residual pesticides were detected in 7 samples, and were over MRLs (Maximum Risk Levels) in 2 samples (1.3%). The mean values of heavy metal contents (mg/kg) were Pb, 0.570; Cd, 0.081; As, 0.082; Hg, 0.0093. The measured values of Pb, As, Hg showed within MRLs. The excess samples of MRLs were 3 samples (changchul 2, cheongung 1) on Cd. The sulfur dioxides were over MRLs in 7 samples (4.6%), hwanggi and gugija. These results will be used to establish on the regulation of commercial medical herbs in Gwangju area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.1
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• pp.55-61
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• 2003

This study was conducted to evaluate distribution and behavior characteristics of heavy metals for tidal flat sediments in the Saemankeum area. The value of heavy metal contents in the tidal flat sediments were higher than that surveyed in 1994, but showing that it's lower when compared with the value of Shiwha lake. Enrichment factors in the tidal flat sediments showed below 1 except for Pb and Zn. Metal excesses was appeared that Cu, Cr, Fe, Mn lacked and Pb, Zn were high. The correlation analysis between heavy metals and organic matters was found high positive relationship (r=0.424$\~$0.839), especially correlation coefficient between ignition loss and oxide Al, Fe, Mn showed high positive relationship above 0.7. The correlation analysis between Brain size and hear metals was found that as grain size was small, heavy metals contents were increased. Correlation coefficient between silt and heavy metals except for Cu, Pb showed high positive relationship as 0.552$\~$0.732.