• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
• /
• pp.46-51
• /
• 2000

Environmental quality regulations are used to establish the maximum permissible concentrations of heavy metals before a site can be deemed to be polluted or contaminated. This paper compares the results obtained by 0.IN HCl extraction and acid extraction method(HNO$_3$+HClO$_4$.HCl). The leaching efficiency of 0.1N HCl extraction is directly proportional to the final pH of leachate, due to the different solubilities of the heavy metals at different pH values, The severe differences between 0.1N HCl-extractable and total metal contents result mainly from the buffering effect of carbonates, present in sediment. samples. Application of sequential extraction experiments to some sediments collected from gully pot in Seoul illustrates a much stronger scavenging effect by Fe and Mn-hydroxides, carbonates and organic phases. As deduced from both sequential extraction and leaching experiments, the relative mobility of heavy metals is found to be: Mn>Zn>>Co>Cd>>Cu>Pb>Cr>Fe, in spite of large differences in heavy metal content and localization. Changes in the physicochemical environments (such as acidification) caused by a traffic accident may result in the severe environmental pollution of heavy metals of surrounding area( surface water and rivers).

• Journal of Korean Society for Atmospheric Environment
• /
• 제18권1호
• /
• pp.25-37
• /
• 2002

The purpose of the study was to survey the distribution patterns of inorganic elements of PM-10 in the various indoor environments and analyze the pollution patterns of aerosol in various places of indoor environment using a pattern recognition method based on cluster analysis and disjoint principal component analysis. A total of 40 samples in the indoor had been collected using mini-vol portable samplers. These samples were analyzed for their 19 bulk inorganic compounds such as B, Na, Mg, Al, K, Ca, Ti, V, Cr, Fe, Ni, Cu, Zn, As, Se, Cd, Ba, Ce, and Pb by using an ICP-MS. By applying a disjoint principal component analysis, four patterns of the indoor air pollutions were distinguished. The first pattern was identified as a group with high concentrations of PM-10, Na, Mg, and Ca. The second pattern was identified as a group with high concentrations B, Mg, At, Ca, Fe, Cu, and Ba. The third pattern was a group of sites with high concentrations of K, Zn. Cd. The fourth pattern was a group with low concentrations PM-10 and all inorganic elements. This methodology was found to be helpful enough to set the criteria standard of indoor air quality, corresponding pollutants, and classification of indoor environment categories when making an indoor air quality law.

• Journal of Korean Society for Atmospheric Environment
• /
• 제12권1호
• /
• pp.101-112
• /
• 1996

Dry and wet deposition is an impertant removal mechanism of the amobient aerosol in the atmospheric environment. Since the deposition flut provides adverse impacts on various encironmental media including aquatic and ecological system as well as human health, it is essential to quantitatively estimate the removal fluxes of many air pollutants. Thus, the purposes of this experimental study are to investigate seasonal deposition flux variations of the total dustfall and various inorganic elements in the local ambient air and then to finally estimate their dry deposition velocities. To perform the study, the total of 90 dustfall samples were collected from January, 1994 thru February, 1995 in 5 different cities of Korea including Seoul, Suwon, Daejon, Kwangju, and Kangrung. Each sample was analyzed by an AAS and an ICP to determine the quantities of the 11 inorganic elements, such as Zn, Cd, Cr, K, Na, Pb, Ca, Fe, Mn, Mi, and Cu. As results, deposition fluxes, soluble/insoluble fractions, and deposition velocities for each element were extensively investigated. The resulting dry deposition velocities of some elements in Suwon were estimated by ranges of 0.57 .sim. 0.87 cm/sec for Zn, 0.35 .sim. 0.45 cm/sec for Pb, 1.25 .sim. 3.52 cm/sec for Ca, 0.21 .sim. 0.48 cm/sec for Fe, 0.95 .sim. 9.31 cm/sec for Mn, and 2.08 cm/sec for Cu.

• Journal of Korea Ship Safrty Technology Authority
• /
• 통권21호
• /
• pp.66-77
• /
• 2006

Stainless steel has been stably used closed by passivity oxidation films(Cr₂O₃) is made by neutral atmospheric environment. However, passivity oxidaton films of the surface of stainless steel occasionally comes to be destroyed in seawater which is influenced by an environment having galogen ion like Cl‾, then, localization corrosion comes to occur Stainless steel 304 for shaft system material of the small-size FRP fishing boat on seawater environments made an experiment on simulation of sacrifical anode(Al, Zn). Through these experiment and study, following results have been obtained ; According to the field inspection and corrosion simulation, the corrosion on the 2nd class stainless steel shaft(STS304) in FRP fishing boat has been verified to occur by crevice corrosion and galvanic corrosion etc., According to the comparison and analysis of Stainless steel 304 was severely corroded, but, protected shaft specimen was not totallay corroded. This result is assumed to be made by the facts that anodic reaction, Fe → fe²+＋ 2e¯, has been restricted by the cathodic protection current of sacrificial anode material.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• 제20권10호
• /
• pp.918-923
• /
• 2007

Fuel cell is a modular, high efficient and environmentally energy conversion device, it has become a promising option to replace the conventional fossil fuel based electric power plants. The high temperature fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. Corrosions in molten electrolytes and the electric conductivity across the oxide scale have crucial characteristics. When molten salts are involved, high temperature corrosions become severe. In this sense, corrosions of alloys with molten carbonates have the most severe material problems. Systematic investigation on corrosion behavior of Fe/21Cr/Ti or Al alloy has been done in (62+38)mol% (Li+K)$CO_3$ melt at $650^{\circ}C$ using the electrochemical impedance spectroscopy method. It was found that the corrosion current of these Fe-based alloys decreased with increasing Al or Ti. And Al addition improved the corrosion resistance of this type of specimen and more improvement of corrosion resistance was observed at the specimen added with Al.

• Journal of the Korean Home Economics Association
• /
• 제42권7호
• /
• pp.63-72
• /
• 2004

This study discussed the dyeing of wool and cotton fabrics with Betel Palm Tree White woolen fabrics and cotton fabrics purchased from HATH (Korea Apparel Testing ＆ Research Institute) were used as experimental fabrics. Using dyeing powder extracted from dyeing material, various temperatures, dyeing times, and pH were used in the dyeing process. Al, Cr, Fe, Cu, and Sn were used as mordant and the absorption was compared with different mordanting methods. The optimum condition for pre-mordanting dyeing was dye concentration of 25% (o.w.f) and mordant concentration of 0.5$^{\circ}$∼1%. Woolen fabric showed an increase of absorption and the maximum absorption was achieved at weak acidity. According to the mordanting methods, woolen fabrics and cotton fabrics were treated with various mordanting agents, a mordant rate of 1:100, at 60$^{\circ}C$, for 30 minutes and dyed with a dyeing material concentration of 25% (o.w.f), at a rate of 1:100, at 60$^{\circ}C$ for 60 minutes. The best dyeing effect w3s achieved at the temperature of 60$^{\circ}C$ for cotton and 80$^{\circ}C$ for wool fabrics. The light fastness of cotton and wool fabrics was low and particularly the fastness to perspiration was decreased with Fe mordanting. I concluded that pre-mordanting method was better than post-mordanting method for cotton and woolen fabrics.

• Proceedings of the Korean Society of Marine Engineers Conference
• /
• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
• /
• pp.232-233
• /
• 2005

Stainless steel has been stably used closed by passivity oxidation films($Cr_2O_3$) is made by neutral atmospheric environment. However, passivity oxidation films of the surface of stainless steel occasionally comes to be destroyed in seawater which is influenced by an environment having halogen ion like $Cl^-$, then, localization corrosion comes to occur. Stainless steel 304 for shaft system material of the small-size FRP fishing boat on seawater environments made an experiment on simulation of sacrifical anode(Al, Zn). Through these experiment and study, following results have been obtained ; According to the field inspection and corrosion simulation, the corrosion on the 2nd class stainless steel shaft(STS 304) in FRP fishing boat has been verified to occur by crevice corrosion and galvanic corrosion etc.. According to the comparison and analysis of Stainless steel 304 shaft materials after simulation leaving unprotected and applying cathodic protection, unprotected shaft specimen of stainless steel 304 was severely corroded, but, protected shaft specimen was not totally corroded. This result is assumed to be made by the facts that anodic reaction, $Fe{\rightarrow}Fe^{2+}$ + $2e^-$, has been restricted by the cathodic protection current of sacrificial anode material.

• 한국해양학회지
• /
• 제12권1호
• /
• pp.41-47
• /
• 1977

The present paper deals with nine kinds of trace metal contents among 79 samples, more than 20 species of edible marine algae collected during 1973∼1975 along the coasts of Korea. Among the metals detected by the atomic absorption spectrometer, Mg content is variable in 2.09∼13.84mg/g-dry on an average and 5.31mg/g-dry in a mean of green, brown and red algae, whereas Fe is 0.148∼2.343 and 0.747mg/g-dry; Mn 0.015∼0.191 and 0.063mg/g-dry; Zn 0.007∼0.082 and 0.030 mg/g-dry; Cu 0.005∼0.054 and 0.017mg/g-dry; Pb 0.0017∼0.082 and 0.0043mg/g-dry Co 0.0009∼0.0024 and 0.0016mg/g-dry; Cd 0.0002∼0.0034 and 0.0011mg/g-dry, and Cr is 0.0007∼0.0074 and 0.0021mg/g-dry, both on an average and in a mean respectively. The trace metal contents in the seaweeds investigated are variable according to species, collecting seasons, places and kinds of metal It is interesting that in Sargassum thunbergii some metal contents such as Fe, Mn, and Zn are specially high in September1974 through the year investigated.

• Proceedings of the Korean Environmental Sciences Society Conference
• /
• 한국환경과학회 2003년도 International Symposium on Clean Environment
• /
• pp.61-64
• /
• 2003

This study was conducted to investigate the chemical characteristics of $PM^{10}$ at Anmyeon-do during the periods from January 1998 to December 2001. The $PM^{10}$ samples ($PM^{10}$) were collected by High Volume Air sampler (HVAS). The measured items were mass concentration of $PM^{10}$ with the major ions ($Cl^{-}$, ${SO_{4}}^{2-}$, ${NO_3}^{-}$, ${Mg}^{2+}$, ${Ca}^{2+}$, ${K}^{+}$etc.) and metallic elements (AI, Fe, Mn, Cr, Zn, Pb etc.). The chemical analysis of major ion components were made by Ion Chromatography (DX-500) and that of metallic elements were made by Inductively Coupled Plasma Spectrometer (ICP-AES, ICP-Mass). The average mass concentration of $PM^{10}$ increased substantially during the heavy dust periods (Asian Dust cases). For water-soluble ions, concentrations of ${Ca}^{2+}$, ${SO_{4}}^{2-}$ and ${NO_3}^{-}$ were remarkably enhanced. Concentrations and mass fraction of crustal elements such as Na, Mg, Ca, Fe, Mn were highly elevated, but those of pollution-derived heavy metals were appreciably decreased. The factor analysis was conducted in order to make the large and diverse data set as manageable levels and to qualitatively examine the relationship between the variables.

• Journal of the Korean Society of Clothing and Textiles
• /
• 제29권6호
• /
• pp.745-752
• /
• 2005

Green tea has various medical effects. It was selected as new natural dyes guessing the effects of the biological activities are still appeared on dyeing. It was examined whether they have the function of Uv-blocker or not. Cotton, linen & Hanji were dyed with Green tea. Al, Cr, Cu, Fe and Sn were selected as the mordant and the UV blocking rate of dyed samples was measured. The results of this study as follows; 1 . The color of dyed samples with Green tea changed yellowish red except Hanji and linen mordanted with Fe. 2. K/S values of dyed samples with Green tea increased by the number of dyeing treatment(p<.01). 3. UVA and UVB blocking rate increased by the number of dyes. Cotton and Linen could block the UV radiation over $93\%$ and Hanji could block over $95\%$ after three times of dyeing. These results suggest that Hanji has possibility far various practical uses of clothing material in beautiful and functional aspect. It could have the biological effects when we put on dyed clothing material with Green tea.