• Economic and Environmental Geology
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• v.28 no.1
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• pp.53-67
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• 1995

Geochemical characteristics of iron-related Ulsan granite was studied in comparison with the Cretaceous granitoids from the metallogenic provinces of copper, lead-zinc and lead-zinc/molybdenum in the Gyeongsang Basin, and the variation of cheminal compositions at the Ulsan granite/serpentinite contact was investigated. Ulsan granite is plotted in the regions of granite and granodiorite of Streckeisen's diagram. It shows differentiation trend of calc-alkali magma, and the magmatic evolution from granodiorite to granite is consistant with the general crystallization path of the Cretaceous the granitoids in Gyeongsang Basin. Differentiation index(D.I.) of Ulsan granite is 86~95, which is higher than those of Jindong granites (D.I.=45~70) and Onjongri granites (D.I.=67~84), and there are differences in the content of some major and trace elements between Ulsan granite and other Cretaceous granitoids. At the Ulsan granite/serpentinite contact $SiO_2$, $K_2O$, $Na_2O$, $Al_2O_3$, Rb, Sr, Ba which are abundant in Ulsan granite decrease toward serpentinite, while T.Fe, MgO, Ni, Cr which are abundant in serpentinite decrease toward Ulsan granite. Therefore, the geochemical characteristics of Ulsan granite is applicable to distinguish iron province from different metallogenic provinces where other Cretaceous granitoids occur in the Gyeongsang Basin, and it is possible to find serpentinite which was intruded by granite on the basis of chemical variations.

• Analytical Science and Technology
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• v.30 no.4
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• pp.182-193
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• 2017

In order to examine the variation characteristics of chemical compositions in relation to the inflow pathways of Asian dust, $PM_{10}$ and $PM_{2.5}$ aerosols were collected at Gosan site of Jeju Island during the Asian dust days between 2010 and 2015, and their chemical compositions were analyzed. The mean mass concentrations of $PM_{10}$ and $PM_{2.5}$ during Asian dust days were $130.0{\pm}90.2$ and $38.2{\pm}24.7{\mu}g/m^3$, respectively. The composition ratios of major secondary pollutants ($nss-SO_4{^{2-}}$, $NH_4{^+}$, $NO_3{^-}$) were high as 53.7 % for $PM_{10-2.5}$ and 90.6 % for $PM_{2.5}$. When the Asian dusts had been transported to the Korean Peninsula via Loess Plateau of central China, the concentrations of $nss-Ca^{2+}$, $NH_4{^+}$, $nss-SO_4{^{2-}}$, and $NO_3{^-}$ increased more noticeably. Whereas in case when the inflow pathways of Asian dust had been through the Bohai bay, the concentrations of the crustal species such as Al, Fe, and Ca were relatively high in coarse particles. The atmospheric aerosols were acidified largely by sulfuric and nitric acids. They were neutralized mainly by calcium carbonate in coarse particle mode passed through Manchuria area, but by ammonia in fine particle mode passed through Loess plateau and Bohai bay. Ammonium salts are assumed to exist as ammonium sulfate and ammonium nitrate in coarse particles, but mostly as ammonium sulfate in fine particles.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.3
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• pp.294-305
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• 2012

The objective of this study is to estimate the chemical compositions and to identify qualitative sources of fall-out particles in study area. Also, this study used a spatial analysis to estimate spatial distributions and average deposition flux. In this study, the chemical compositions of fall-out particle samples collected at Muncheon lake from May 2010 to January 2011 were analyzed by ICP and IC. The monthly trend of deposition fluxes for fall-out particles showed highest in June ($107.61kg/km^2/day$) and lowest in October ($22.22kg/km^2/day$). The average fluxes of Fe, Si, Al, Zn and Ba are 0.44, 0.24, 0.20, 0.17, $0.09kg/km^2/day$, respectively. Also, the average fluxes of $NO_3^-$, $SO_4^{2-}$, $NH_4^+$, $Ca^{2+}$, and $Na^+$ are 6.48, 5.01, 4.96, 1.75, $1.37kg/km^2/day$, respectively. A Factor analysis identified four sources such as 1) nonferrous metal, motor vehicle, and agriculture, 2) soil, 3) field burning, incineration, and 4) road dust and oil burning. The IDW (inverse distance weighting) spatial analysis method was used to estimate spatial distribution and average deposition flux for fall-out particles. A total average deposition fluxes estimated in Muncheon lake were 936.15 kg/month. The spatial distribution trend of deposition flux showed higher at site 1 and 2 than at site 3, 4 because local road is adjacent to the site 1 and 2.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.533-539
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• 2014

Mine wastes such as acid mine drainage (AMD) can cause the detrimental effects on surrounding environment, thereby eventually threatening human health. Main objective of this study was to evaluate the neutralizing effect of fly ash (FA) as a stabilizing material AMD. Field plot was constructed in a coal waste depot which has caused aluminium-whitening adjacent to the stream. Different mixing ratios of FA were applied on a top of the soil, and then the physicochemical properties of runoff and soil were monitored. Constructed plots were as following: control (mine waste only (W)), mine waste + 20% ($w\;w^{-1}$)of FA (WC20M), mine waste + 40% ($w\;w^{-1}$)of FA (WC40M), and WC40M dressed with a fresh soil at the top (WC40MD). Result showed that initial pH of runoff in control was 5.09 while that in WC40M (7.81) was significantly increased. For a plot treated with WC40M, the concentration of Al in runoff was decreased to $0.22mg\;L^{-1}$ compared to the W as the control ($4.85mg\;L^{-1}$). Moreover, the concentration of Fe was also decreased to less than half at the WC40M compared to the control. Application of FA can be useful for neutralizing AMD and possibly minimizing adverse effect of AMD in mining area.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.464-468
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• 2005

산업활동으로 인해 발생하는 슬래그 등의 폐기물을 적절히 처리하는 방법으로서는 저비용 처리형태와 자연계에서 슬래그 등의 특성을 고려한 Filter 기능을 수행할 수 있도록 수질이 악화된 하천이나 정체수역에 투입시켜 수질을 개선시킬 수 있는 방법의 도입이 필요하다. 현재 POSCO에서 발생하는 슬래그와 폐콘크리트의 화학적 성분은 주로 $CaO,\;SiO_2,\;Al_2O_3,\;Fe_2O_3$ 등으로 이루어져 있으며, 침전유발물질 및 흡착성물질이 공존하고 있다. 다공질 형태의 비표면적을 가지고 있어서 정화용 필터로 이용하기에 좋은 이점을 가지고 있다. 슬래그나 폐콘크리트를 Mattress/Filter 채움재 및 수질정화용 여재로 활용하면 폐기물처리, 자원 재활용 그리고 수질 환경 개선의 세 가지 효과를 동시에 얻을 수 있는 방법이 된다. 본 연구에서는 슬래그와 폐콘크리트를 활용한 정체수역에서 정화시스템의 정화특성을 조사하기 위하여 유입수와 유출수의 pH, 용존산소, 질소, 인 등을 측정하여 비교하였다. 수질개선을 위한 Mattress/Filter 시스템의 기본개념은 하천의 오염된 물이 Mattress/Filter의 공극사이를 통과하면서 채움재에 형성된 생물막이 수질 개선과정에서 나타나는 접촉작용, 생물 흡착작용, 생물산화의 분해작용 등을 촉진시키도록 하였다. Mattress/Filter를 이용한 수중 수질개선시스템에서 채움재로 제철폐기물인 슬래그와 건설폐기물인 폐콘크리트를 사용함으로써 Mattress/Filter의 다공성 및 넓은 표면적이라는 특성에 따른 물리적$\cdot$화학적$\cdot$생물학적 작용이 촉진되고 있음을 확인할 수 있었으며, 그 결과 정체수역에 설치한 Mattress/Filter는 다공질 속에서 쉽게 생물막을 형성시키고 유기물의 흡착을 촉진시켜 오염물질을 정화하는데 필요한 자정작용의 효과 증대와 수질개선을 촉진시킬 수 있는 자연생태적 하천정화시스템임을 확인할 수 있었다.

• Korean Journal of Medicinal Crop Science
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• v.18 no.4
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• pp.273-279
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• 2010

The study result survey platycodon cultivation regions of Jinju(2), Sacheon(4), Hapcheon(3), Haman(3), and Sancheong(3) of Gyongnam regarding chemical properties of soil, inorganic nitrogen phosphorus by type of composition is as follows: pH and EC value were highest where platycodon cultivated for under 3 years in soils. Content of O.M equal to or less than 25 mg $kg^{-1}$, the average value for platycodoncultivation in korea. Content of exchangeable calcium in soils were 12, 14 $cmol^+kg^{-1}$ in Hapcheon and Haman regions where platycodon was cultivated for two years which is 2~3 time higher level compared with the average upland soil of korea. Water solution boron confirmed approximated level of 3.0 mg $kg^{-1}$ in all survey regions, and the finding is about five times higher than average upland soil of korea which is 0.5 mg $kg^{-1}$. In the case of nitrogen, a significant difference was found depending on cultivation regions and continuous culture. Content of nitrogen in soils were difference according to cultivation area and continuous culture. The composition ratio according to the type of inorganic phosphorus showed the highest in order of Al-P > Ca-P > Fe-P > Saloid-P in all survey regions except for Hapcheon (five, seven years cultivated soils). The correlation showed high significance between available phosphate and inorganic phosphorus.

• Journal of the Mineralogical Society of Korea
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• v.10 no.2
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• pp.114-125
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• 1997

The purpose of this study is to clarify the geological occurrence, mineralogical, physico-chemical and thermal properties of the sericite ore which located in Chungha area, Kyungsangbuk-do. The geology of this area are composed mainly of hornfels and some felsite porphyry. The sericitic ore is classified into sericite, sericite-quartz and quartz-sericite ore according to mineral assemblages. Mineral components in sericite ore are mainly sericite with minor quartz, apatite, sphene, zircon, ilmenite, bismuthinite, iron oxide and etc. Sericite-quartz ore are mainly composed of sericite and quartz. Accessary minerals are muscovite, epidote, zircon, sphene, iron oxide and etc. The chemical compositions of K2O, Al2O3, & Ignition loss in sericite and sericite-quartz ore increase than that of the host rock, while the composition of SiO2, Na2O & Fe2O3 decrease. Sericite and sericite-quartz ore are characterized by the specific gravity of 2.35 and 2.44, the pH of 4.36 cP and 2.36 cP respectively. The result of size analyses of sericite ore is 11.3% in grain volume concentration between 12.9 $\mu\textrm{m}$ and 11.1$\mu\textrm{m}$, and 32.3% between 9.6$\mu\textrm{m}$ and 12.9$\mu\textrm{m}$. The thermal expansivity of sericite and sericite-quartz ore show the similar pattern. The sericite ore shows the thermal expansivity of 0.31% at 50$0^{\circ}C$, 0.39~0.75% at 600~1,00$0^{\circ}C$ and 0.74% at 1,10$0^{\circ}C$. The sericite-quartz ore show the thermal expansivity of 0.29% at 50$0^{\circ}C$, 0.36~0.72% at 600~1,000% and 0.71% at 1,10$0^{\circ}C$.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.17.2-17.2
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• 2011

Double-walled carbon nanotubes (DWCNTs) were grown with vertical alignment on a Si wafer by using catalytic thermal chemical vapor deposition. This study investigated the effect of pre-annealing time of catalyst on the types of CNTs grown on the substrate. The catalyst layer is usually evolved into discretely distributed nanoparticles during the annealing and initial growth of CNTs. The 0.5-nm-thick Fe served as a catalyst, underneath which Al was coated as a catalyst support as well as a diffusion barrier on the Si substrate. Both the catalyst and support layers were coated by using thermal evaporation. CNTs were synthesized for 10 min by flowing 60 sccm of Ar and 60 sccm of H2 as a carrier gas and 20 sccm of C2H2 as a feedstock at 95 torr and $750^{\circ}C$. In this study, the catalyst and support layers were subject to annealing for 0~420 sec. As-grown CNTs were characterized by using field emission scanning electron microscopy, high resolution transmission electron microscopy, Raman spectroscopy, and atomic force microscopy. The annealing for 90~300 sec caused the growth of DWCNTs as high as ~670 ${\mu}m$ for 10 min while below 90 sec and over 420 sec 300~830 ${\mu}m$-thick triple and multiwalled CNTs occurred, respectively. Several radial breathing mode (RBM) peaks in the Raman spectra were observed at the Raman shifts of 112~191 cm-1, implying the presence of DWCNTs, TWCNTs, MWCNTs with the tube diameters 3.4, 4.0, 6.5 nm, respectively. The maximum ratio of DWCNTs was observed to be ~85% at the annealing time of 180 sec. The Raman spectra of the as-grown DWCNTs showed low G/D peak intensity ratios, indicating their low defect concentrations. As increasing the annealing time, the catalyst layer seemed to be granulated, and then grown to particles with larger sizes but fewer numbers by Ostwald ripening.

• Korean Journal of Materials Research
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• v.20 no.4
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• pp.181-186
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• 2010

Since it was developed by Joseph Aspdin, cement has been a common construction materials up to the present time. However, there are trace constituents in cement clinker. One of the trace constituents included in cement clinker, chromium, has become prominent and highly noticed lately as a social issue both inside and outside of this country because it affects the human body negatively. The aim of the present study was to investigate the concentration of water-soluble hexavalent chromium in cement clinker by using industrial by-products. For that reason, raw materials were prepared to add different $SiO_2$, $Al_2O_3$, and $Fe_2O_3$ sources. After the raw materials such as the limestone, the sand and the clay, iron ore was pulverized and mixed, and the raw meal was burnt at about $1450^{\circ}C$ in a furnace with an oxidizing atmosphere. The part in the raw materials of the clinker was substituted with slag, sludge, etc. and this was used to manufacturing cement clinker. To investigate the water-soluble hexavalent chromium content in clinker, raw meal was prepared by changing the modulus, the type, and the content of clinker materials and tested concentrations of hexavalent chromium in the clinkers. To determine $Cr^{+6}$ formation of the clinker, tests were done with raw meals adding chromium by using different industrial by-products. Consequently because the chromium was to be included in the raw materials of the clinker, production of Portland cement clinker was included with the chromium. Also, the chromium was converted into hexavalent chromium in the burning process.

• 보존과학연구
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• s.26
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• pp.103-126
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• 2005

Coprostanol is a metabolic product of cholesterol, formed by microbial action in the mammalian gut. This chemical compound is the major sterol in human and has been routinely studied as a biomarker of sewage pollution in marine and lacustrinesediments. This has led to the search for coprostanol as a biomarker in archaeologicalsoils, in order to detect the presence of fecal material. In this study, five samples of archaeological soils excavated at Wanggung ri, Iksancity, were used to assess the possibility of using coprostanol as indicators of ancient human activity in archaeological areas. The sampled soils were analyzed MXRD,EDXRF for their physical and chemical properties. And coprostanol was analysed byGC/MSD, using SIM method to detect and quantify specific compound. The results showed the soils were composed of quartz and feldspars, inorganicelement such as $SiO_2$, $Al_2O_3$, $Fe_2O_3$ etc. Moreover, the result from the analysis wasindicated that the specific compound is coprostanol. The coprostanol was determined at $0.16~1.01\mug$/g in the range of concentrations. This finding indicate that clear promise exists for the exploitation of coprostanol as biomarker of ancient human activity inarchaeological survey. Therefore such studies can serve to increase the confidence we place on biomarker-based methodologies for assessing fecal pollution. The application of this methodology has proved a simple and effective way of searching for that pattern in successively more aged deposits either known or suspected to contain fecal material. And the more scientific analysis of the soils will be showed to utility of the area ancient dietary life style, ancient environment.