• Journal of the Korean Magnetics Society
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• v.25 no.5
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• pp.169-173
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• 2015

Fe compounds of volcanic basalt samples distributed at the Hantan riverside in Cheorwon were investigated by means of X-ray diffractometry (XRD), X-ray fluorescence spectroscopy (XRF) and $M{\ddot{o}}ssbauer$ spectroscopy. We found that samples were typical basic rock which consisted of augite, anorthite, albite and sanidine etc. They had the total amount of iron compounds including hematite (${\alpha}-Fe_2O_3$) varies from 6.20 w% to 12.8 w% depending on the different regions by XRF. The $M{\ddot{o}}ssbauer$ spectra of the samples were consisted of three doublets. The balance state of Fe ions of all samples were chiefly $Fe^{2+}$, and $Fe^{2+}/Fe^{3+}$ ratios were 2.27~3.42.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.5
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• pp.397-404
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• 2009

Effects of ceramic filler types and dose on the low temperature sintering and dielectric properties of ceramic/$CaO-Al_2O_3-SiO_2$ (CAS) glass composites were investigated. All of the specimens were sintered at $850{\sim}900^{\circ}C$ for 2 h, which conditions are required by the low-temperature co-firing ceramic (LTCC) technology. Ceramic fillers of $CaCO_3$, $Al_2O_3$, $CaCO_3-Al_2O_3$ mixture, and $CaCO_3-Al_2O_3$ compound ($CaAl_2O_4$), respectively, were used. The addition of $Al_2O_3$ yielded the crystalline phase of alumina, which was associated with the inhibition of sintering, while, $CaCO_3$ resulted in no apparent crystalline phase but the swelling was significant. The additions of $CaCO_3-Al_2O_3$ mixture and $CaAl_2O_4$, respectively, yielded the crystalline phases of alumina and anorthite, and the sintering properties of both composites increased with the increase of filler addition and the sintering temperature. In addition, the $CaAl_2O_4$/CAS glass composite, sintered at $900^{\circ}C$, demonstrated good microwave dielectric properties. In overall, all the investigated fillers of 10 wt% addition, except $CaCO_3$, yielded reasonable sintering (relative density, over 93 %) and low dielectric constant (less than 5.5), demonstrating the feasibility of the investigated composites for the application of the LTCC substrate materials.

• The Journal of the Petrological Society of Korea
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• v.20 no.1
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• pp.1-21
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• 2011

Eoil basalt in the Eoil basin and Yeonil basalt and its related volcanic rocks in Guryongpo and Daebo area were researched and analyzed to purse the tectonic settings and magma characteristics of those Tertiary volcanic rocks in the south-east Korean peninsula. It is highly suggested that zoning, resorption and sieve texture in plagioclase and reaction rim in pyroxene indicate unstable tectonic environments and complex volcanism in the study area. Volcanic rocks from Janggi basin are identified as basalt and basaltic andesite in TAS diagram and sub-alkaline series in terms of magma differentiation. $Na_2O$ and $K_2O$ show positive trend however FeO, CaO, MgO and $P_2O_5$ indicate negative trend in Harker variation diagram with $SiO_2$. Basaltic rocks from Eoil area are identified as calc-alkaline series in AFM diagram and show medium K series calc-alkaline in $K_2O-SiO_2$ diagram. Compatible trace elements of Co, Ni, V, Zn, and Sc in Yeonil basalt show negative trend with crystallization but incompatible trace element of Ba, Rb show positive trend with $SiO_2$ 0.81~1.00 of $Eu/Eu^*$ value suggests minor effect of plagioclase fractionation in Yeonil basaltic rocks. Plagioclase composition of Eoil basalt ranges from $An_{63.46-98.38}\;Ab_{1.62-32.96}\;Or_{0-3.58}$ (anorthite-labradorite) in core to $An_{40.89-82.44}\;Ab_{17.10-46.43}\;Or_{0-12.68}$ (bytownite-labradorite) in rim. $^{87}Sr/^{86}Sr$ and 143Nd;t44Nd ranges 0.704090~0.704717 and 0.512705~0.512822 respectively. Negative linear trends in 87Sr/86Sr and $^{143}Nd/^{144}Nd$ correlation diagram indicate that magma produced Yeonil basalt and basaltic andesite has been originated as partial melting product of mantle wedge by subducting Pacific plate affected by oceanic crust with less effect of continental crust indicating calc-alkaline magma characteristics.

• Resources Recycling
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• v.15 no.4 s.72
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• pp.3-12
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• 2006

The feasibility for the employment of manganese nodule as an adsorbent for $SO_{2}$ gas has been investigated. The specific surface area of manganese nodule particle, which used in the experiments, was ca. $221.5m^{2}/g$ and the content of sulfur in manganese nodule was observed to significantly increase after $SO_{2}$ was adsorbed on it. The EPMA for the distilled water-washed and methanol-washed manganese nodule particle after $SO_{2}$ adsorption showed that its sulfur content was slightly decreased to 14.7% and 13.1% respectively, from 15.4% before washing. The XRD analysis of manganese nodule showed that todorokite and birnessite, which are manganese oxides, and quartz and anorthite were the major mineralogical components and weak $MnSO_{4}$ peaks were detected after $SO_{2}$ was adsorbed on manganese nodule. For an comparative investigation, limestone was also tested as an adsorbent for $SO_{2}$, however, no peaks for $CaSO_{4}$ were found by XRD analysis after the adsorption of $SO_{2}$. As the size of adsorbent increased, time for breakthrough was decreased and the adsorbed amount of $SO_{2}$ was also diminished. The $SO_{2}$ adsorption was hindered when its flow rate became high and the adsorption capacity of manganese nodule was observed to be superior to that of limestone. In addition, the mixture of manganese nodule and limestone did not show an increase in the adsorption of $SO_{2}$. Finally, as the temperature was raised, the adsorbed amount of adsorbate on manganese nodule was found to be decreased.

• Journal of the Mineralogical Society of Korea
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• v.28 no.1
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• pp.61-69
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• 2015

While the macroscopic properties and eruption style of basaltic and phonolitic melts are different, the microscopic origins including atomic structures are not well understood. Here we report the atomic structure differences of glass in diopside-anorthite eutectic composition (basaltic glass) and phonolitic glass using high-resolution 1D and 2D solid-state Nuclear Magnetic Resonance (NMR). The $^{27}Al$ MAS NMR spectra for basaltic glass and phonolitic glass show that the full width at half maximum (FWHM) of Al for basaltic glass is about twice than phonolitic glass, suggesting the topological disorder of basaltic magma is larger than that of phonolitic magma. The $^{27}Al$ 3QMAS NMR spectra for basaltic glass and phonolite glass show much improved resolution than the 1D MAS NMR, resolving Al and Al. Approximately 3.3% of Al is observed for basaltic glass, demonstrating the configurational disorder of basaltic magma is larger than phonolitic magma. This result confirms that the topological disorder of Al in basaltic glass is larger than that of phonolitic glass. The observed structural differences between basaltic glass and phonolitic glass can provide an atomistic origin for change of the macroscopic properties with composition including viscosity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.176-176
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• 2009

Influences of dose and particle size of $Al_2O_3$ filler and sintering time on the dielectric properties of $Al_2O_3$ filler/CaO-$Al_2O_3-SiO_2$ (CAS) glass composites were investigated with a view to applying the composites to the substrate material in low temperature co-firing ceramic (LTCC) technology. The increased addition of $Al_2O_3$ filler with the particle size of 1 ${\mu}m$ monotonically decreased the density of the sintered specimen at a given temperature, while sintering of the 10 wt% $Al_2O_3$ added specimen at $925^{\circ}C$ for 2 h demonstrated 96.0 % of the relative density, dielectric constant of 6.34, and quality factor of 2,760 GHz. As for the influence of the particle size of the $Al_2O_3$ filler, there existed an optimum particle size (30 ${\mu}m$) to ensure successful densification (96.5 %) of the 10 wt% $Al_2O_3$/CAS composites at $925^{\circ}C$ for 2 h, at which condition the specimen demonstrated dielectric constant of 5.45 and quality factor of 3,740 GHz. When the influence of the sintering time of the 10 wt% $Al_2O_3$) (30 ${\mu}m$) added specimen was investigated at the sintering temperature of $925^{\circ}C$, an overly long sintering time degraded dielectric properties due to the over-sintering and the significant growth of the second phase such as anorthite, while the sintering for 4 h demonstrated 96.58 % of the relative density, dielectric constant of 5.4, and quality factor of 4,050 GHz. These results demonstrate the feasibility of the investigated material as the substrate material in LTCC technology.

• Journal of the Korean Society of Groundwater Environment
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• v.7 no.2
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• pp.73-88
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• 2000

The geochemistry of the $CO_2$-rich waters ($Pco_2\leq$about 1 atm) in NE part of the Kangwon province was investigated. The $CO_2$-rich waters can be divided to three types based on chemical compositions: Na-$HCO_3$, Ca-Na-$HCO_3$and Ca-$HCO_3$types. The water chemistry indicates that these type waters were evolved through reaction with host rocks by supply of deep-seated $CO_2$during deep circulation, and their geochemical environments in depth might have been different each other. The dissolution process of plagioclase is important in water/granite interactions and its solubility change according to reaction temperature played an important role in the determination of chemical compositions. The higher reaction temperature coincides with the lower different in solubility between albite and anorthite. It means that calcium is mainly released to the water in the lower temperature, whereas sodium in the higher temperature due to high Na/Ca ratio in plagioclase. The application of various chemical geothermometries on the $CO_2$-rich waters shows that the calculated reservoir temperature of Na-$HCO_3$type (about 15$0^{\circ}C$) is higher than those of Ca-$HCO_3$type. Therefore, we now interpret the recognized chemical difference was mainly due to the difference of reaction temperature. Considering normal thermal gradient, we can understand that the Na-$HCO_3$type was evolved from deeper crustal depth than the Ca-$HCO_3$type.

• Economic and Environmental Geology
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• v.7 no.2
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• pp.45-62
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• 1974

Scheelite deposits in Sangdong mine are divided into three parallel vein groups, namely "Hanging-wall vein" which is located in the lowest parts of Pungchon Limestone, "Main vein" the most productive vein replaced a intercalated limestone bed in Myobong slate, "Foot-wall veins" a group of several thin veins parallel to main vein in Myobong slate. Besides the above, there are many productive quartz veins imbedded in the above veins and Myobong slate. Molybdenite and wolframite are barren in the former three veins group but associates only in quartz veins. Both main vein and foot-wall veins show regular zonal distribution, quartz rich zone in the center, hornblende rich zone surrounding the quartz rich zone and diopside rich zone in the further outside to the marginal parts of the vein. According to the distribution of three main minerals, quartz, hornblende and diopside the main vein can be divided into three zones which are in turn grouped into 7 subzones by distinct mineral paragenesis. They are summerized as follows: A. Diopside rich zone: 1. garnet-diopside.fl.uorite subzone 2. diopside-zoisite-quartz subzone 3. diopside-plagioclase subzone B. Hornblende rich zone: 4. hornblende-diopside-quartz subzone 5. hornblende-quartz-chlorite subzone 6. hornblende-plagioclase-quartz.sphene subzone C. Quartz rich zone: 7. quartz-mica-chlorite subzone The foot-wall veins can similarly be divided by mineral paragenesis into 3 zones, 6 subzones as follows: A. diopside rich zone: 1. garnet-diopside-quartz.fl.uorite subzone 2. garnet-diopside-wollastonite subzone B. Hornblende rich zone: 3. quartz-hornblende-chlorite subzone 4. hornblende-plagioclase-quartz subzone 5. hornblende-diopside-quartz subzone C. Quartz rich zone: 6. quartz-mica subzone The hanging-wall vein is generally grouped into 9 subzones by the mineral paragenesis which show random distribution. They are as follows: 1. diopside-garnet-fluorite subzone 2. diopside-zoisite-quartz subzone 3. diopside-hornblende-quartz-fluorite subzone 4. wollastonite-garnet-diopside subzone 5. hornblende-chlorite-quartz subzone 6. quartz-plagioclase-hornblende-sphene subzone 7. quartz-biotite subzone 8. quartz-calcite subzone 9. calcite-altered minerals subzone Among many composing minerals, garnet specially shows characteristic distribution and optical properties. Anisotropic and euhedral grossularite is generally distributed in the hanging wall vein and lower parts of the main vein, whereas isotropic and anhedral andradite in the upper parts of the main vein. Plagioclase (anorthite) and sphene are distributed ony near the foot-wall side of the aboveveins. wollastonite is a characteristic mineral in upper parts of the hang-wall vein. Molybdenite is distributed in the upper parts of quartz veins and wolframite in lower parts of quartz veins.

• Journal of Conservation Science
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• v.27 no.1
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• pp.13-30
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• 2011

This study compared Pottery, Hwaecheongware, Buncheongware and Whiteware pieces excavated in Hakbong-ri of Chungnam analytically by observing their refined structures and estimating their firing temperature. As a result, base soil components of the specimens were mostly similar to those of typical Buncheongware, but the content of the fluxing agent was rather high, and it seemed that the Whiteware had been made with fairly different components from those of other sherds. Although the glaze showed less difference than base soil in general, the content of the glaze changed according to the decorating methods of Buncheongware. Based on the SEM-EDS analysis, it was found that the base soil components of the ceramics seemingly rather different were actually different and the analysis on the fine crystals of the base soil, the anorthite in the glaze and crystals in the ironing part, and the components and contents of white earth showed there were some noticeable points in the process of making each of the sherds. In the refiring experiment to estimate the firing temperature, mostly similar results were gained as $1150^{\circ}C$ to $1200^{\circ}C$ for pottery, $1100^{\circ}C$ to $1150^{\circ}C$ for Hwaecheongware, and $1100^{\circ}C$ to $1200^{\circ}C$ for iron-brown Buncheongware however, the results imply good quality Whiteware was burnt at above $1300^{\circ}C$ while bad quality Whiteware was burnt at a temperature far lower than that. Thus, there was clear difference between Whiteware sherds and other kinds of sherds.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.837-843
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• 2010

This research investigated classification of clay activity degree by different clay mineral components. Based on compositions of different clay and oxide minerals within 390 soil series in Korea, 7 soils were selected to analyze for CEC and specific surface area of clay minerals. As a result, soils were mainly composed with Chlorite originated from sandstone, Smectite originated from Andesite porphyry and combination of Allophane and Ferrihydrite originated from volcanic ash, if the ratio of CEC value to clay content (degree of clay activity) was greater than 0.7. If the degree of clay activity was ranged between 0.3 and 0.7, soils were composed mainly with Kaolin originated from anorthite. Soils with this ratio also was composted with combinations of Kaolin, Illite and Vermiculite originated with river deposits. When the degree of the activity was less than 0.3, soils were commonly red-yellowish color and composed with two different minerals. One type of composition was Kaolin originated from granite and granite gneiss and the soils contained Geothite and Hematite. The other type was composited mainly with Illite and Vermiculite minerals originated from granite. These soils contained Gibbsite, Geothite and Hematite. The degree of clay activity was highly related with CEC and specific surface area. The greater degree of the activity displayed greater values of clay CEC and specific surface area. It is not easy to measure actual quantity and compositions of clay minerals, while the degree of clay activity can be measured from routine soil analyses. As a conclusion, the degree of clay activity may be not just a simple but also powerful tool to estimate physical-chemical properties of soils and to evaluate the soil classification in Korean soils.