• Journal of environmental and Sanitary engineering
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• v.4 no.2 s.7
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• pp.101-107
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• 1989

In order to investigate harmful trace in commercial teaproducts. The contents of copper, lead, cadmium, zinc, chromium, manganese and iron were studied in this paper. The samples studied were Youlmoo tea(7) Arrow root tea(9) Ginger tea(4) collected from markets in Seoul area and analysis of seven metals by means of Automic absorption spectrometry. The results obtained were as follows : Lead contents is ranged from 0.06 to 0.72 ppm, cadmium from ND to 0.17 ppm, copper from 0.8 to 16.7 ppm, zinc from 10.4 to 40.4 ppm, manganess from 2.7 to 16.5 ppm, chromium from 0.04 to 4.7 ppm, iron from 7.9 to 55.7 ppm.

• Mycobiology
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• v.42 no.4
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• pp.427-431
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• 2014

Mitochondrial protein Nfu1 plays an important role in the assembly of mitochondrial Fe-S clusters and intracellular iron homeostasis in the model yeast Saccharomyces cerevisiae. In this study, we identified the Nfu1 ortholog in the human fungal pathogen Cryptococcus neoformans. Our data showed that C. neoformans Nfu1 localized in the mitochondria and influenced homeostasis of essential metals such as iron, copper and manganese. Marked growth defects were observed in the mutant lacking NFU1, which suggests a critical role of Nfu1 in Fe-S cluster biosynthesis and intracellular metal homeostasis in C. neoformans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.2
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• pp.187-193
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• 1990

Ganoderma lucidum has been widely used not only as ingredients in herbal medicine but also in pharmacological soft drinks. The author collected for analysis of content of 8 kinds of heavy metal(Cd, pb, Hg, Cu, Mn, Fe, As) in soil and cluture soil in an around the Taegu area including Sang Ju, Non Gong, Keum Ho, and Weol Bae. THe toxic content in Gaoderma lucidum showed relatively low level as in cadmium lead mercury arsenic : 0.8-0.13ppm 0.17-1.43ppm 0.02-0.32ppm 0.01-0.19ppm respectively : in copper mangenese zinc and iron : 0.93-4.29ppm, 0.37-2.18ppm 1.02-1.65ppm, 4.57-11.04ppm those grown in soil showed higher percentages of content than those grown on logs in lead copper zinc and iron by 43.2% 68.6%, 20.3% and 43.2% respectively. The content of heavy metals in those grown in soil and culture soil tended to be higher in the areas near factories of industrial complexes especially in manganese and iron. The content of heavy metals in soil and culture soil appeared lower than the mean values of Korean Soil. No interrelationship was found in the content of heavy metals between those of Ganoderma lucidum grown on logs and those grown in soil. In case of pot cultivation however the mushroom spawns are grown originally in soil which seems to influence the degree of content of heavy metals of media.

• Progress in Superconductivity and Cryogenics
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• v.19 no.1
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• pp.22-25
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• 2017

Steel slag has been considered as an industrial waste. A huge amount of slag is produced as a byproduct and the steel slag usually has been dumped in a landfill site. However the steel slag contains valuable resources such as iron, copper, manganese, and magnesium. Superconducting magnetic separation has been applied on recovery of the valuable resources from the steel slag and this process also has intended to reduce the waste to be dumped. Cryo-cooled Nb-Ti superconducting magnet with 100 mm bore and 600 mm of height was used as the magnetic separator. The separating efficiency was evaluated in the function of magnetic field. A steel slag was ground and analyzed for the composition. Iron containing minerals were successfully concentrated from less iron containing portion. The separation efficiency was highly dependent on the particle size giving higher separating efficiency with finer particle. The magnetic field also effects on the separation ratio. Current study showed that an appropriate grinding of slag and magnetic separation lead to the recovery of metal resources from steel slag waste rather than dumping all of the volume.

• Journal of the Korean Society for Heat Treatment
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• v.1 no.1
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• pp.13-23
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• 1988

The hardenability of alloyed ductile cast irons was studied for 54 different alloy compositions obtained from eight commercial and laboratory foundries. The alloying elements investigated for their effects on hardenability were Si(2.0 to 3.0%), Mn(0.0 to 0.8%), Mo(0.0 to 0.6%), Cu(0.0 to 1.5%), and Ni(0.0 to 1.5%). Two hardenability criteria, a first-pearlite hardenability criterion and a half-hard hardenability criterion, were used to determine hardenability of ductile irons. Prediction models for each hardenability criterion were developed by multiple regression analysis and were well agreed with previous experimental results. Molybdenum was the most potent hardenability promoting element followed by manganese, copper and nickel ; silicon had little effect on hardenability and reduced the hardenability as silicon content increased. When alloying elements were presented in combination, strong synergistic effects on the hardenability were observed especially between molybdenum, copper and nickel. The hardenability of ductile iron was strongly influenced by austenitizing temperature. Increasing austenitizing temperature up to $955^{\circ}C$, hardenability increased gradually but decreasing rate and then decreased as temperature increased above $955^{\circ}C$. Unless reducing segregation by very long-time annealing treatment, the hardenability of ductile iron was not significantly influenced by segregation of alloying elements.

• The Korea Journal of Herbology
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• v.33 no.6
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• pp.87-92
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• 2018

Objectives: The aim of the study was to analyze the constituents of Pyrolusitum, which was used to eliminate static blood and inflammation, to establish the basis of clinical application. Methods: Qualitative analysis was performed by X-Ray Diffraction (XRD) using the sample as a powder, and the elemental content of granular sample was measured by X-Ray Fluorescence (XRF). 1 M hydrochloric acid and 5% sodium hydroxide aqueous solution were added to observe the changing shape, respectively. Results: Qualitative analysis by XRD revealed that the Pyrolusitum samples used in the study contained quarts and kaolinite. Quantitative analysis by XRF revealed that the manganese content in the samples used in the study was 6.16% on average, while iron was contained the highest amount of 22.99%. The minor constituents include 1.08% of titanium, 0.30% of barium, 0.18% of lead, 0.06% of zirconium, 0.05% of chromium, 0.04% of zinc, 0.03% of cadnium, 0.02% of nickel, 0.01% of arsenic, 0.01% of copper, 0.01% of rubidium, 0.01% of strontium, 0.00% of molybdenum, respectively. And cobalt, which is reported to be a constituent of Pyrolusitum, was not detected at all in the samples of the study. Pyrolusitum was dissolved in dark brown when it was put into 1 M hydrochlorid acid, and there was brown precipitate when sodium hydroxide solution was added to Pyrolusitum and stirred. Conclusions: It was found that manganese and iron were the major constituents of Pyrolusitum, and it could be identified by using concentrated hydrochloric acid and sodium hydroxide solution.

• Journal of Korea Foundry Society
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• v.12 no.3
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• pp.230-237
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• 1992

The purpose of present investigation is to obtain ductile cast iron with ferrite-bainite matrix by pearlite-bainite transformation treatment. Ductile cast irons having three kinds of Mn ampunt had been manufactured. Mn increased pearlite volume fraction iin as-cast ductile cast iron. Ductile cast irons of different pearlite fraction were austenitized at $875\;^{\circ}C$ for 230-350 sec or $925\;^{\circ}C$ for 130-170 sec followed by austempering at $300\;^{\circ}C$ or $400\;^{\circ}C$ for the various periods of time from 5 to 30 min. When specimen was austenitixed for 130 sec at $925\;^{\circ}C$ and for 230 sec at $875\;^{\circ}C$, pearlite was transformed into austenite. Bainite around graphite was found at $925^{\circ}C$ for 170 sec. Bainite in grain boundary of ferrite was happened at $875^{\circ}C$ for 350 sec. During the austempering process, acicular bainite was precipitated at $300^{\circ}C$ and lath bainite was precipitated at $400^{\circ}C$. Increment in manganese content restrained bainitic transformation. Retained austenie was of little quantity.

• 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.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.91-96
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• 2003

To monitor the heavy metal exposure conditions of Feral Pigeons Columba livia, we collected them at commercial area, industrial area, park area and resident area in Seoul. In feathers, iron concentrations were significantly different among habitats(ANOVA, p<0.05), and were the highest at park area. Manganese concentrations were relatively higher at industrial and park area than other areas(ANOVA, p<0.05). In case of copper levels were the significantly highest at park area(ANOVA, p<0.05). Zinc, lead and cadmium had no difference among habitats. Correlation between livers and feathers concentrations were highly significant to copper(r²=0.983, p<0.01) and cadmium(r²=0.632, p<0.01), but iron, zinc, manganese and lead were not significantly different.

• Journal of Soil and Groundwater Environment
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• v.13 no.2
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• pp.62-69
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• 2008

In this study physicochemical characteristics and stability of various manganese coated sands (MCS) prepared with different methods were evaluated. In addition, removal efficiencies of As(III) by each MCS were compared. Four different MCSs were used; B-MCS prepared by baking method, W&D-MCS prepared by wetting and dry method, NMCS prepared during the water treatment process and Birm which is a commercial MCS widely used for the removal iron and manganese. The manganese content in each MCS was following order: Birm (63,120 mg/kg) > N-MCS (10,400 mg/kg) >W&D-MCS (5,080 mg/kg) > B-MCS (2,220 mg/kg). Birm showed the least solubility (% basis) in acidic conditions. As(III) oxidation efficiency of B-MCS was continuously increased as the solution pH decreased. While As(III) oxidation efficiency of N-MCS and Birm was minimum around neutral pH. The increased As(III) oxidation efficiency above neutral pH for N-MCS and Birm could be due to the competitive adsorption of $Mn^{2+}$, which was produced from reduction of $MnO_2$, onto the surface of aluminum and manganese oxides.