• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.5 no.2
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• pp.24-30
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• 1999

The migration mechanism of trace elements, Pb, Cd, Cu, Zn and Sn from brass food-contact utensiles was investigated. The migration of metals from brass was affected by the migration temperature (30, 60, 80 and $95^{\circ}C$), the simulant pH (2.5, 4.3, 6.0 and 7.0) and the migration time (30, 90, 180 and 360 min.). The amount of Pb migration was maximum at $95^{\circ}C$ with pH 2.5. This study indicated that the equilibrium of Pb migration was reached at 180 minutes. The mechanism of Pb migration was investigated with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). To correlate the relations between the migration and the content of Pb in brass samples, ten brass samples having known content of Pb (the quantities of Pb in brass ; 0, 0.02, 0.09, 0.1, 0.2, 0.5, 0.9, 1.4, 5.4 and 9.2% (w/w)) were tested in the following conditions, 4% acetic acid, $95^{\circ}C$ and 30 minutes. The result represented that content of Pb in brass samples must be below 0.2% (w/w) to satisfy the 1.0 ppm (as Pb) of Korea Food Code.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.133-147
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• 2004

Environmental quality(water and sediment) was analyzed in the tidal flat of Saemangum of Jeonbuk Province, the west coast of Korea, using the 101 sediment samples and 69 water samples collected in September 4~13, 2001. Major water quality parameters with the means of 69 surface water samples are as follows; $25.51{\pm}0.68^{\circ}C$ for water temperature, $29.88{\pm}5.01$ for salinity, $1.40{\pm}0.78mg/L$ for COD, $0.352{\pm}0.417mg/L$ for DIN, and $0.027{\pm}0.023mg/L$ for phosphate, respectively. Higher values were found at the subestuary of Dongjin and Mangyung River, and lower values at the Saemangum embayment and Gomso Bay. There was a significant negative correlation between salinity and the other water quality parameters(p<0.0001) such as COD, nutrients, SS and N/P. This correlation suggested that the major pollution sources be from terrestrial inputs through tributaries in this area. Principal component analysis clearly revealed a spatial variation of water quality; stations with higher values of nutrients and COD located subestuary of tributaries. 14 sediment quality parameters including 8 trace metals were measured using the 101 surface sediment samples. Average values for the parameters are as follows; Al $2.28{\pm}0.92%$, Cd $0.61{\pm}0.27ppm$, Cu $8.95{\pm}4.06ppm$, Fe $1.19{\pm}0.37%$, Mn $182.31{\pm}77.45ppm$, Ni $10.83{\pm}4.97ppm$, Pb $15.20{\pm}4.35ppm$, Zn $41.34{\pm}34.62ppm$, COD $2.68{\pm}1.85mg/g\;dry$, AVS $0.04{\pm}0.08mg/g\;dry$, IL $1.29{\pm}1.08%$, water content $24.11{\pm}4.49%$, TN $0.02{\pm}0.02%$, TC $0.22{\pm}0.30%$. Spatial variations of sediment quality were not clear as water quality. Some higher values were found at the subestuary of Gum River and lower values at the other area. There was a significant positive correlation between the heavy metal concentrations and organic materials within the sediment(p<0.05). Enrichment factors showed the ranges of 1~2 for most of the metals in the sediment except zinc(1~6), indicating no serious exogenous input of heavy metals in the study area. Also, the heavy metal concentrations in the sediment were within the ranges found at the natural marine environments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.3
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• pp.185-192
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• 2008

We have studied effect of water treatment sludge (WTS) on trace metals of sorghum hybrid (Sorghum bicolor (L.) Moench). In the present report it was for cadmium (Cd) content on background correction (BGC) mode with an atomic absorption spectrophotometer. The four treatments were Control, Compost, Alum + nitrogen, phosphorus, potassium (NPK), Compost + NPK. In the analysis, burner height of the atomic absorption spectrophotometer was adjusted to three levels; 3 mm, 6 mm, 9 mm. As a conclusion, 3 mm and 6 mm burner height conditions were better than 9 mm height for Cd analysis. And the conditions for widening the range, the mean, and the standard deviation (SD) values of observed absorbances as well as the condition for lessening the mean of observed background values are necessary for getting the better measuring of Cd. At the present experiment, 6 mm burner height condition is the best among the three burner heights.

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.25-43
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• 1994

To estimate the factors to the inclination of the criminal violence, the content of trace minerals and toxic metals in the scalp hair were measured during the period from May 1992 to October 1992. One hundred eleven violent and 89 nonviolent criminal inmates of Taegu Correctional Institute were selected. The inmates of violent criminals were imprisoned by murder, robber, rape, injury and violent acts. Those of nonviolent criminals were swindle, larceny, and adultery and had no history of institutional violence. The contents of two toxic metals (cadmium, lead) and five trace minerals (Cu, Fe, Zn, Mg, Na) were determined by an atomic absorption spectrophotometer (IL. 551). The contents of cadmium and lead in hair of violent criminals were significantly higher as $0.56{\pm}0.14ppm,\;11.53{\pm}3.32ppm$, respectively, than $0.42{\pm}0.20ppm,\;9.63{\pm}4.31ppm$ of nonviolent group (p<0.01). But the level of copper was significantly lower than nonviolent group (p<0.05). The factors that had a significant correlation with the inclination of violence in multiple logistic regression analysis were cadmium (odds ratio=98.09), unmarried (odds ratio=0.39), many times of criminal history(odds ratio=1.57) and residence of rural area (odds ratio=0.44). The results suggest that the sub-toxic contents of cadmium and lead in the hair may be of potential effect on behavior, and the mineral analysis may be an important adjunctive diagnostic procedure. Further studies into this problem are necessary.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1270-1276
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• 2013

Laver, a red algae belonging to the genus Porphyra tenera, is one of the most widely consumed edible seaweeds in Korea, China, and Japan. Lavers are usually consumed in dried, roasted, and seasoned forms to improve their palatability. We evaluated the composition of amino acids, minerals, and trace heavy metals in these three differently cooked forms of laver. The moisture and ash contents of three differently cooked lavers ranged from 1.49~9.69% and 6.07~10.31%, respectively. The crude protein and lipid content ranged from 17.24~36.88% and 0.52~42.42%, respectively. Dried laver was found to be a good source of amino acids such as taurine, alanine, and glutamic acid (871.10 mg, 833.53 mg, and 719.77 mg per 100 g dry weight, respectively). Laver was a good source of macro and micro minerals such as K, Ca, Mg, Na, P, I, and Fe, although laver more extensively cooked (roasted and seasoned) contained less minerals compared to the dried form. Mercury levels in the three differently cooked forms of laver were all less than 100 ng/g dry weight (the limit of detection with our methodology). The levels of arsenic were the most abundant elements in the differently cooked laver. There was a clear variation, depending on the cooking process, in terms of amino acid, mineral, and trace metal contents of laver.

• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.43-57
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• 2005

Twelve bottom sediments and three cores were collected in Juam reservoir for a study on transportation, which was controlled by particle grain size (2mm-200{\mu}m,\;200-100{\mu}m,\;100-50{\mu}m,\;50-20{\mu}m,\;<20{\mu}m), and vertical distribution of heavy metals. Sediment cores were sliced into 2 to 5 cm intervals to measure heavy metal concentrations in interstitial water and sediments with depth. Pb isotopic compositions of core samples were determined to calculate sedimentation rate. Regardless of sampling sites, levels of heavy metals and trace elements in bottom sediments are nearly constant with mean values of $14.9\;{\mu}g/g\;for\;As,\;0.81{\mu}g/g\;for\;Cd,\;30.7{\mu}g/g\;for\;Cu,\;34.7{\mu}g/g\;for\;Ni,\;63.3{\mu}g/g\;for\;Pb\;and\;87.9{\mu}g/g\;for\;Zn$. In general, Cu, Pb, Zn, Wi, and Cr in fraction of $<20{\mu}m$ exhibit the highest concentration, but content of As is the highest in grain size of $2\;mm-200\;{\mu}m$ and $200-100\;{\mu}m$. Fe and Mn occur as the dissolved compositions of the highest concentrations in interstitial waters and increase in their concentrations toward lower part of cores. On the contrary, concentrations of Zn and Cu show the highest value in the uppermost part in cores, suggesting these elements are released from reductive dissolution of hydroxides and oxidation of organic matters under different redox conditions. The highest accumulations of Cu, Ni, Pb, and Zn contents in the sediment cores are observed at 0-4 cm layers, and concentrations of Cu and Pb are especially high, implying these heavy metals are originated from anthropogenic sources. The apparent sedimentation rate estimated using unsupported $^{210}Pb$ is 0.91 cm $year^{-1}$, corresponding about 10 cm sedimentation in total depth since construction of Juam dam. These results will provide available information for management of bottom sediment in Juam reservoir.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.550-560
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• 2012

This study was performed to investigate the physicochemical properties of sea urchin ($Anthocidaris$ $crassispina$, $Pseudocentrotus$ $depressus$, $Hernicentrotus$ $pulcherrimus$) roe as a processed or canned food by steaming treatment. Proximate compositions of $A.$ $crassispina$ roe and $P.$ $depressus$ roe were similar, but water, crude ash, and carbohydrate contents of $H.$ $pulcherrimus$ roe showed little differences. Proximate compositions of sea urchin roe showed slight differences with steaming time, raw samples showed no differences. Glycine content of the three raw sea urchin roe samples showed the highest concentration among free amino acids, followed by arginine, alanine, and lysine, in order. Total free amino acid contents of raw sea urchin roe were 754.70 mg% ($A.$ $crassispina$), 567.75 mg% ($P.$ $depressus$), and 449.44 mg% ($H.$ $pulcherrimus$). Total free amino acid content of 5 min steaming sample was highest among steaming and canning conditions. ATP, ADP, and AMP contents of raw $P.$ $depressus$ roe sample was higher than those of $A.$ $crassispina$and $H.$ $pulcherrimus$ roe. Major fatty acids of the three raw sea urchin roe samples were myristic acid, palmitic acid, and EPA. S.F.A. content of raw samples of $A.$ $crassispina$and $H.$ $pulcherrimus$ roe was higher than U.F.A content, whereas U.F.A. content of $P.$ $depressus$ roe was highest among the three raw samples. For minerals K, P, Fe, and Zn contents were highest in $A.$ $crassispina$roe while Ca, Mg, Na, and Cu contents were highest in $H.$ $pulcherrimus$ roe. For heavy metals, Cd, Pb and As were detected in all samples in trace amounts under the criteria of the Korea food codex.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.1
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• pp.42-46
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• 2004

Deep Ocean Water (DOW) is formed within restricted area including polar sea (high latitude) by cooling of surface seawater and globally circulating in the state of isolation from surface seawater. Although it is not as obvious as estuaries mixing, brine ground water is mixture of recirculated seawater and ground water. Seawater having high osmotic pressure infiltrates into an aquifer which is connected to the sea. In order to clarify the characteristics of deep ocean water and brine ground water, we investigated their origins, chemical compositions, water qualities and resources stabilities. While concentrations of stable isotopes (/sup 18/O and ²H) in seawater is 0‰, those in brine ground water is on meteoric water line or shifted toward oxygen line. It means that origin of brine ground water is different than that of deep ocean water. The ions dissolved in seawater (Na, Ca, Mg, K) are present in constant proportions to each other and to the total salt content of seawater. However deviations in ion proportions have been observed in some brine ground water. Some causes of these exception to the rule of constant proportions are due to many chemical reactions between periphery soil and ground water. While DOW has a large quantity of functional trace metals and biological affinity relative to brine ground water, DOW has relatively small amount of harmful bacteria and artificial pollutants.

• Resources Recycling
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• v.32 no.1
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• pp.21-32
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• 2023

Because the application of lithium has gradually increased for the production of lithium ion batteries (LIBs), more research studies about recycling using solvent extraction (SX) should focus on Li⁺ recovery from the waste solution obtained after the removal of the valuable metals nickel, cobalt and manganese (NCM). The raffinate obtained after the removal of NCM metal contains lithium ions and other impurities such as Na ions. In this study, we optimized a selective SX system using di-(2-ethylhexyl) phosphoric acid (D2EHPA) as the extractant and tri-n-butyl phosphate (TBP) as a modifier in kerosene for the recovery of lithium from a waste solution containing lithium and a high concentration of sodium (Li⁺ = 0.5 ~ 1 wt%, Na⁺ = 3 ~6.5 wt%). The extraction of lithium was tested in different solvent compositions and the most effective extraction occurred in the solution composed of 20% D2EHPA + 20% TBP + and 60% kerosene. In this SX system with added NaOH for saponification, more than 95% lithium was selectively extracted in four extraction steps using an organic to aqueous ratio of 5:1 and an equilibrium pH of 4 ~ 4.5. Additionally, most of the Na⁺ (92% by weight) remained in the raffinate. The extracted lithium is stripped using 8 wt% HCl to yield pure lithium chloride with negligible Na content. The lithium chloride is subsequently treated with high purity ammonium bicarbonate to afford lithium carbonate powder. Finally the lithium carbonate is washed with an adequate amount of water to remove trace amounts of sodium resulting in highly pure lithium carbonate powder (purity > 99.2%).

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.339-344
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• 2006

A lot of organic wastes have been produced from diverse industries, they must be tested by the regulation of fertilizer control act if reuse the organic wastes for agricultural utilization. The regulation has had only two criteria; the content of organic matter and 8 heavy metals. This study was conducted to evaluation trace element (boron, cobalt, molybdenum, and selenium) and distribution of organic compounds with different classification for complement the regulation in 16 organic waste materials(62 samples) collected from different regions and industries. Contents of boron(leather industry sludge, $154.2mg\;kg^{-1}$; food company sludge, $57.1mg\;kg^{-1}$), cobalt(industrial area sewage sludge, $95.2mg\;kg^{-1}$; metropolitan sewage sludge, $22.9mg\;kg^{-1}$), molybdenum(metropolitan sewage sludge, $40.1mg\;kg^{-1}$; food company sludge, $16.8mg\;kg^{-1}$), selenium (fiber industry sludge, $28.1mg\;kg^{-1}$; leather industry sludge, $16.9mg\;kg^{-1}$; food company sludge, $15.9mg\;kg^{-1}$) were highest compare to the other organic wastes. Total PAHs contents were the highest in paper-mill manufacture($3,462ug\;kg^{-1}$), and among the 16 PAHs, naphthalene, phenanthrene, pyrene, fluoroanthene, Anthracene and acenaphthene were detected more clearly than others in all kinds of organic resources.