• Environmental Engineering Research
• /
• v.14 no.2
• /
• pp.134-139
• /
• 2009

In this study, oxidation of As (III) as well as removal of total arsenic by adsorbents coated with single oxides or multi-oxides (Fe (III), Mn (IV), Al (III)) was investigated. In addition, multi-functional properties of adsorbents coated with multi-oxides were evaluated. Finally, application of activated carbon impregnated with Fe or Mn-oxides on the treatment of As (III) or As (V) was studied. As (V) adsorption results with adsorbents containing Fe and Al shows that adsorbents containing Fe show a greater removal of As (V) at pH 4 than at pH 7. In contrast adsorbents containing Al shows a favorable removal of As (V) at pH 7 than at pH 4. In case of iron sand, it has a negligible adsorption capacity for As (V) although it contains 217.9 g-Fe/kg-adsorbent, Oxidation result shows that manganese coated sand (MCS) has the greatest As (III) oxidation capacity among all metal oxides at pH 4. Oxidation efficiency of As (III) by IMCS (iron and manganese coated sand) was less than that by MCS. However the total removed amount of arsenic by IMCS was greater than that by MCS.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.1 no.1
• /
• pp.89-99
• /
• 1991

The metal concentrations in lungs from 12 coal workers' pneumoconiosis(CWP) patients and 6 controls, who were not exposed occupationally to coal mine dust and metals during their life time, were analyzed by atomic absorption spectrophotometry. 1. Copper, lead, nickel, magnesium, manganese, zinc and iron concentrations in lungs of CWP patients were $1.10{\pm}0.088$, $1.12{\pm}0.068$, $0.22{\pm}0.020$, $113.7{\pm}1.31$, $0.19{\pm}0.012$, $10.2{\pm}1.54$, $426.7{\pm}2.63{\mu}g/g$ wet weight. 2. Copper, lead, nickel, magnesium, manganese, zinc and iron concentrations in lungs of controls were $1.10{\pm}0.013$, $0.85{\pm}0.007$, $0.10{\pm}0.008$, $87.6{\pm}1.29$, $0.18{\pm}0.005$, $10.6{\pm}1.44$, $164.9{\pm}3.29{\mu}g/g$ wet weight. 3. The ratios of concentrations for copper, lead, nickel, magnesium, manganese, zinc, and iron in lungs for CWP patients and controls were 1 : 1, 1.32 : 1, 2.20 : 1, 1.30 : 1, 1.06 : 1, 0.92 : 1, 2.58 : 1, respectively. There were significant differences in concentrations of lead, nickel, magnesium, iron by group(p<0.05). 4. There was no significant difference in metal concentrations of right upper lobe, right lower lobe, left upper lobe and left lower lobe for both CWP patients and controls (p>0.05, p>0.05). 5. In CWP patients lead was well correlated with nickel showing a rank correlation coefficient of 0.533, and zinc was correlated with copper showing a rank correlation coefficient of 0.476. 6. The concentrations of copper, nickel, maganese, and zinc in Korean CWP patients were lower than those in foreign CWP patients.

• Korean Journal of Soil Science and Fertilizer
• /
• v.3 no.1
• /
• pp.23-28
• /
• 1970

The effect of wollastonite and manganese dioxide on the growth of rice on an acid sulfate soil were investigated in pot experiment. 1. Since aluminum content in the leachate of soil was reduced with increasing the pH and these chemical changes in the leachate were more pronounced by applying wollastonite, aluminum toxicity in flooded paddy rice was overcome by applying wollastonite, or flooding. 2. Poor growth of rice with iron toxicity-like symptoms on the untreated acid sulfate soil may be caused by excess iron and sulfur. Plants applied wollastonite, however, grew normally and did not show any symptoms. Iron and sulfur contents in the plant was reduced by applying wollastonite. 3. Because of the iron content in the both leachate and plant can be lowered by applying wollastonite, iron-toxicity was averted by applying the wollastonite. 4. Application of manganese dioxide in combination with wollastonite did not counteracted iron content in the plant as compared with the wollastonite treatment. 5. The application of wollastonite increased the dry weight of straw and grain yield. Manganese dioxide with wollastonite caused the increase of number of spickelets per panicles and ripened grains as compared with wollastonite. 6. From these results it can be concluded that the major cause of the poor growth of rice on acid sulfate soil is iron toxicity and the Fe-toxicity can be reduced by application of wollastonite.

• Korean Journal of Plant Resources
• /
• v.22 no.6
• /
• pp.540-545
• /
• 2009

Aloe (Aloe vera L.), cucumber (Cucumis sativus L. var. tuberculatus Gabaj.) and sponge.gourd (Luffa cylindrica L.) are well utilized in Asian countries as traditional medicines and cosmetics, or foods. And we carried out an experiment to see if there are some specific ratios among trace metals on the plants. Though the metal concentrations varied significantly depending on the sampling periods, aloe gel is high in iron (Fe) and calcium (Ca). Cucumber fruit juice is also high in iron (Fe) and potassium (K). Sponge.gourd sap contains a high amount of zinc (Zn) and calcium (Ca). The uses of the previous 3 plant parts are considered to have some relations to their different ratios and of their trace metals.

• Journal of Korea Foundry Society
• /
• v.27 no.4
• /
• pp.159-166
• /
• 2007

Effects of alloying elements on the mechanical properties of 3.60wt%C-2.50wt%Si ductile cast iron with annealing and normalizing were investigated. Yield and tensile strengths were increased from 278 and 415 MPa to 316 and 440 MPa respectively as manganese content was increased upto 0.45wt% while elongation was decreased from 24.2 to 5.0%. The formers were increased and the latter was decreased with the increased amount of copper, molybdenum or nickel added. Meanwhile the tensile strength of annealed specimen was increased with the amount of alloying elements added, it was decreased by annealing. It was increased greatly by normalizing and the amount of alloying elements added except molybdenum.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.51 no.4
• /
• pp.43-47
• /
• 2009

Soil aggregation is an important part of influencing the soil behaviors in reducing rainfall-runoff and soil erosion, aeration, infiltration, and root penetration. Some inorganic materials such as clay minerals, Fe and Al oxides/hydroxides, and calcium carbonate can act as cementing agents within macroaggregates. The objective of this study was to determine the effects of different cementing agents (Fe, Mn, and Al) on soil aggregate formation in reclaimed tidelands. Water stable aggregate ratio and MWD (mean weight diameter) were higher in iron dioxides treatment than two other treatments. This result indicates significant correlation between soil aggregate formation and iron dioxides.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.7
• /
• pp.473-482
• /
• 2009

In this study, iron and manganese coated sand (IMCS) was prepared by mixing Joomoonjin sand with solutions having different molar ratio of manganese ($Mn^{2+}$) and iron ($Fe^{3+}$). Mineral type of IMCS was analyzed by X-ray diffraction spectroscopy. Removal efficiency of arsenic through As(III) oxidation and As(V) adsorption by IMCS having different ratio of Mn/Fe was evaluated. The coated amount of total Mn and Fe on all IMCS samples was less than that on sand coated with iron-oxide alone (ICS) or manganese-oxide alone (MCS). The mineral type of the manganese oxide on MCS and iron oxides on ICS were identified as ${\gamma}-MnO_2$ and mixture of goethite and magnetite, respectively. The same mineral type was appeared on IMCS. Removed amount As(V) by IMCS was greatly affected by the content of Fe rather than by the content of Mn. Adsorption of As(V) by IMCS was little affected by the presence of monovalent and divalent electrolytes. However a greatly reduced As(V) adsorption as observed in the presence of trivalent electrolyte such as $PO_4\;^{3-}$. As(III) oxidation efficiency by MCS in the presence of NaCl or $NaNO_3$ was two times greater than that in the presence of $PO_4\;^{3-}$. Meanwhile a greater As(III) oxidation efficiency was observed by IMCS in the presence of $PO_4\;^{3-}$. This was explained by the competitive adsorption between phosphate and arsenate on the surface of IMCS.

• Journal of Nutrition and Health
• /
• v.38 no.2
• /
• pp.151-160
• /
• 2005

The purpose of this study was to compare the mineral status of postmenopausal vegetarian women with those of the omnivores, and to investigate the relationship between dietary pattern and minerals status in postmenopausal Korean women. The research group was composed of vegetarian women (n = 38), all of them were seven day adventists, who had been on vegetarian diet over 20 yrs. Their anthropometric measurements, dietary intakes, and blood mineral concentrations were compared to age matched omnivores controls (n = 38). The average age of vegetarians and omnivores were 60.7 yrs and 60.5 yrs, respectively and there was no significant difference. The mean daily energy intake of vegetarians and omnivores were 1518.5 kcal and 1355.5 kcal, respectively and their was no significant difference. The mean calcium intake of vegetarians (492.6 mg) was not significantly different from that of omnivores (436.6 mg). The vegetarians consumed significantly greater quantities of magnesium (p < 0.001), iron (p < 0.001), copper (p < 0.001), manganese (p < 0.001) and dietary fiber (p < 0.05). There were no significantly differences in serum calcium, magnesium and manganese levels between vegetarians and omnivores. However, serum levels of phosphorus (p < 0.01), iron (p < 0.05), ferritin (p < 0.01), zinc (p < 0.001) and copper (p < 0.05) were significantly lower than those of omnivores. In conclusion, vegetarian postmenopausal women may have low bioavailability of iron, zinc and copper. Therefore it was needed that further study on mineral bioavailability of vegetarian diet. (Korean J Nutrition 38(2): 151～160, 2005)

• Korean Journal of Metals and Materials
• /
• v.48 no.2
• /
• pp.154-162
• /
• 2010

A fundamental study of the distillation behavior of ferromanganese alloy melts was carried out at 1773 K and 0.1333 kPa (=1 Torr). During the distillation of ferromanganese alloy melts under reduced pressure, manganese vaporizes preferentially to phosphorus and other solute elements. High purity manganese metal with a very low content of solute elements can be obtained by distillation of ferromanganese alloy melts. The evaporation of manganese is suppressed as the carbon content of ferromanganese alloy melt increases due to the decrease of activity and vapor pressure of the manganese. When the carbon content of ferromanganese alloy melt is high, melt droplets are ejected from the bath, especially in the early stages of the distillation, and the solute elements in the splashed droplets contaminate the condensed material. The ejection of melt droplets is presumed to be caused by the increase of melting temperature and viscosity of the surface layer of melt due to the enrichment of solute elements such as carbon and iron.

• Microbiology and Biotechnology Letters
• /
• v.20 no.6
• /
• pp.693-698
• /
• 1992

The resistant effect of several heavy metal ions to Serratia marcescens strain P was studied by the method of minimal inhibitory concentration(MIC), and testing for their metal biosorption. S. marcescens strain P showed a good survival in the presence of high concentrations of some metal ions, namely cadmium, lead, iron, magnesium, and manganese. Copper had the most inhibitory effect among tested. The MIC value was ranged from 0.79 to 1.58 mM. Cells of S. marcescens strain P exhibit an abnormally long lag phase when incubated in high concentrations of zinc and cadmium. Pigment production was reduced by zinc and cadmium, but enhanced by lead and iron. S. marcescens strain P was resistant to ampicillin, tetracycline, cefamandole and chloramphenicol with minimal inhibitory concentration of 128 $\mu$g/ml, 32 $\mu$g/ml, 256 $\mu$g/ml, and 8 $\mu$g/ml, respectively. The kinetics study of biosorptive uptake by S. marcescens strain P revealed that 16.59% of cadmium and 35.38% of lead were eliminated from the media.