• The Journal of the Petrological Society of Korea
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• v.26 no.4
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• pp.311-325
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• 2017

Peridotite xenoliths in middle Miocene alkaline basalt from the Mt. Baekdu area are mainly anhydrous spinel lherzolites, displaying coarse-grained protogranular texture. These xenoliths have late-stage secondary orthopyroxene replacing olivine as the metasomatic mineral and glass formed along the grain boundaries. The studied xenoliths are characterized by the high $Mg{\sharp}[=100{\times}Mg/(Mg+Fe_{total})$ atomic ratio] of olivine, orthopyroxene and clinopyroxene (89~92) and the $Cr{\sharp}[=100{\times}Cr/(Cr+Al)$ atomic ratio] of spinel (10~29). Based on major-element data, the studied xenoliths are similar to those from the abyssal peridotites. Clinopyroxenes of the xenoliths are mostly enriched in incompatible trace elements, exhibiting two types of REE patterns: (1) LREE-depleted with $(La/Yb)_N$ of 0.1~0.2 and $(La/Ce)_N$ of 0.4~0.8. (2) LREE enriched with $(La/Yb)_N$ of 2.2~3.8 and $(La/Ce)_N$ of 1.2~1.6. The calculated equilibrium temperatures and oxygen fugacities resulted in $920{\sim}1050^{\circ}C$ and ${\Delta}fO_2(QFM)=-0.8{\sim}0.2$, respectively. It is suggested that the Mt. Baekdu peridotite xenoliths represent residues left after variable degrees of melt extraction(less than 15 vol%), which was subsequently subjected to different degrees of modal/cryptic metasomatism by silica- and LREE-enriched fluids (or melts).

• Environmental Engineering Research
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• v.16 no.3
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• pp.159-164
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• 2011

This study examined the emission characteristics of impure gas-like hydrogen sulfide and siloxane contained in landfill gas (LFG) and investigated the effect of impure gas on LFG utility facilities. As a result of an LFG component analysis from eight landfills in the same environment, hydrogen sulfide averaged 436 ppmv (22-1,211 ppmv), and the concentration of total siloxane averaged 7.95 mg/$m^3$ (1.85-21.18 mg/$m^3$). In case of siloxane concentration by component, the ratio of D4 (average 3.79 mg/$m^3$) and D5 (average 2.64 mg/$m^3$) indicated the highest level. Different kinds of scales were found on the gas air heater (GAH) and inside the boiler. The major component of scale from the GAH was $Fe_2O_3$ of 38.5%, and it was caused by hydrogen sulfide. Other scale was found on the bottom and the wall of the boiler and the scale was silicon dioxide of 92.8% and 98.9%. The silicon dioxide scale was caused by combustion of siloxane. As a result of a scanning electron microscopy analysis, the structure of the silicon dioxide scale from the boiler was an immediate filamentous type. Consequently, as silicon dioxide scale is bulky, such bad effects were worsening, as an interruption in heat conduction, increase in fuel consumption, damage to the boiler by overheating, and clogged emission pipeline could occur in LFG utility facilities.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.107-112
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• 2001

The various components of sigumjang were analyzed according to fermentation time. Aerobic bacteria were increased with fermentation time. Yeasts and molds were increased until 3 days after fermentation and then not changed. Six free sugars, 3 volatile organic acids and 6 non-volatile organic acids were detected. The content of free amino acids was $1,407.9{\sim}3,053.9\;mg%$. Glutamic acid was most abundant component among the amino acids, followed by phenylalanine, arginine and valine. The ratio of essential amino acid was $34.4{\sim}37.0\;mg%$. The content of mineral was $12,966.7{\sim}13,864.5\;mg%$. Potassium was the most abundant in quantity among the minerals in sigumjang except sodium which was added artificially. The principal fatty acids were linoleic acid, palmitic acid and oleic acid. The ratio of unsaturated fatty acids was $76.3{\pm}1.1%$. As a result of sensory evaluation, the highest score was obtained 3 to 5 days after fermentation.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.34-42
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• 1988

To investigate the effects of paper sludge on seasonal variations of volatile lower fatty acids in paddy soil, paper sludge was applied to pots at the rate of either 300, 600, 900 or 1,200 kg/l0a which was either preadjusted at a C/N ratio of 30 : 1 or not adjusted. The decomposition rate of paper sludge, the evolution of $CO_2$, and the fractions of volatile lower fatty acids in the soil were determined. The results are summarized as follows: 1. Paper sludge was decomposed to $35{\sim}44%$, and its C/N ratio was $55{\sim}82$, respectively, at 120 days after treatment. 2. The evolution of $CO_2$, in the soil was proportional to the amount of paper sludge added. Significant positive correlations were observed the $CO_2$ evolution was compared with the decomposition rate of paper sludge, and volatile fatty acid contents in soil. 3. Acetic, propionic, butyric, i-butyric, valeric and i-valeric acids were identified in all the soils investigated. The content of the total volatile fatty acids in the soil increased with as the application of paper sludge increased. The formation of the acids was the highest at 25 days after treatment, and thereafter the contents of the acids decreased as time elapsed. 4. The volatile fatty acids in the soil inhibited the growth of paddy rice in early stages. The contents of acetic, propionic and i-valeric acids in the soil negatively, correlated with the uptake of N, $P_2O_5$, $K_2O$, CaO, MgO and $SiO_2$ in the paddy rice at 25 days after transplantation. In addition, the uptake of $P_2O_5$ and CaO in the paddy rice negatively correlated with the content of butyric acid in the soil. 5. The content of total volatile fatty acids positively correlated with the content of $Fe^{++}$ and $Mn^{++}$ in the soil at 25 days after transplantation. A significantly positive correlation was observed between $Fe^{++}$ and acetic acid contents in the soil.

• Resources Recycling
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• v.9 no.1
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• pp.36-43
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• 2000

This study was carried out for treatment and reuse of inorganic sludge from Fenton process at B dyeing wastewater treatment plant. The parameters for pilot-scale treatment system were derived from the results of this study. It was found that $COD_{cl}$ of the treated effluent became lower than 100 mg/l approximately on the optimal reaction condition. 2nd sludge which was generated after redissolving sludge was analyzed, and it showed that reduction ratio of ash in 2nd sludge and total dry sludge weight in comparison with current sludge were 85% and 65%. Also Fe salt in sludge was redissolved about 90~95% of initial Fe by weight. It was estimated almost ￦350,000,000 for sludge reuse process. It was estimated saving of about ￦1,300,000 per day (￦420,000,000 per year) in operating cost based on 30,000 $m^3$/d treatment, which these were about ￦430,000 per day in chemical, ￦1,100,000 per day in sludge transportation and ￦200,000 per day in equipment maintenance. Payback period with interest charge for investment cost was estimated about 10.5 months. Also, net present value (NPV) was ￦792,000,000 and internal rat of return (IRR) was about 110%.

• The Journal of the Petrological Society of Korea
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• v.6 no.1
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• pp.19-33
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• 1997

This study reports the results about the petrography and geochemical characteristics of 10 representative volacanic rocks. The Cretaceous volcanic rocks distributed in the vicinity of the Kageo island composed of andesitic rocks, dacitic welded tuff, and rhyolitic rocks in ascending order. Sedimentary rock is the basement in the study area covered with volcanic rocks. Andesitic rocks composed of pyroclastic volcanic breccia, lithic lapilli tuff and cryptocrystallin lava-flow. Most dacitic rocks are lapilli ash-flow welded tuff. Rhyolitic rocks consists of rhyolite tuff and rhyolite lava flow. Rhyolite tuff are lithic crystal ash-flow tuff and crystal vitric ash-flow tuff with somewhat accidental fragments of andesitic rocks, but dacitic rocks. The variation of major and trace element of the volcanic rocks show that contents of $Al_2O_3$, FeO, CaO, MgO, $TiO_2$ decrease with increasing of $SiO_2$. On the basis of Variation diagrams such as $Al_2O_3$ vs. CaO, Th/Yb vs. Ta/Yb, and $Ce_N/YB_N$ vs. $Ce_N$, these rocks represent mainly differentiation trend of calc-alkaline rock series. On the discriminant diagrams such as Ba/La and La/Th ratio, Rb vs. Y + Nb, the volcanic rocks in study area belongs to high-K Orogenic suites, with abundances of trace element and ternary diagram of K, Na, Ca. According to the tectonic discriminant diagram by Wood, these rocks falls into the diestructructive continental margin. K-Ar ages of whole rocks are from andesite to rhyolite $97.0{\pm}6.8~94.5{\pm}6.6,\68.9{\pm}4.8,\61.5{\pm}4.9~60.7{\pm}4.2$ Ma, repectively. Volcanic rocks in study area show well correlation to the Yucheon Group in terms of rock age dating and geochemcial data, and derived from andesitic calc-alkaline magma that undergone low pressure fractional crystallization dominated plagioclase at <30km.

• Korean Journal of Heritage: History & Science
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• v.46 no.4
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• pp.108-125
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• 2013

This study examined the actual reconstruction drawing, composite mineral, particle size and property test, fine organic matters, color differences and main ingredients of the earthen mold excavated in Dongcheon-dong, Gyungju. The cross-section of the inner mold and outer mold divides into inside (1st layer) and outside (2nd layer), with organic matters mixed outside. The cross-section has been altered due to heat and form removal agent. X-ray analysis revealed that the layer was made of minerals with high transmissivity and only quartz particles were observed through a polarizing microscope. The inside of cross-section in SEM observation identified enlarged air gap, with crack developed in the center, but no changes observed on the outside. The particle size of the composites is almost the same for the inner mold and outer mold and is silt clay loam. The ratio between silt clay and silt clay loam was about 2.7:1 and 2.9:1 respectively. In the property test, the density and absorption rate of inner mold and outer mold were similar, but porosity was different, with inner mold of 27.36% and outer mold of 31.09%. The color difference of cross-section seems to have been caused by the spread of soot on the 1st layer surface for removal of form or by the covering of ink to protect the 1st layer. Composite mineral analysis revealed the same composition for the inner mold and outer mold, except for the magnetite that was detected in the inner mold alone. As for the main ingredient analysis, the average content of $SiO_2$ was 71.64% and that of $Al_2O_3$ was 14.59%. As for the sub-ingredients, $Fe_2O_3$ was 4.51%, $K_2O$ 3.06%, $Na_2O$, MgO, CaO, $TiO_2$, $P_2O_5$ and MnO was less than 2%.

• Economic and Environmental Geology
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• v.49 no.5
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• pp.335-347
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• 2016

The mineralogical and geochemical characteristics of diverse carbonate rocks can be investigated by using VNIRSWIR(visible near infrared-short wavelength infrared) spectroscopic analysis as a rapid, nondestructive, and inexpensive tool. Comparing whole rock analysis to VNIR-SWIR spectroscopic analysis, the analytical method was investigated to estimate CaO contents, mud impurity, and whiteness of carbonate rocks involved in high-grade limestones in the field. We classify typical carbonate rocks in the upper Pungchon Formation in high-grade limestone mine area such as the Gangweon, Chungmu and Baegun mine in the Jeongseon area. The results show that powdered specimen has much higher reflectance than cutted specimen between the same sample. Whiteness is highly correlated with reflectance(0.99) for powdered specimen. The absorption of mineral mixtures shifts in position as a result of the mass ratio of calcite and dolomite in the Chungmu mine by changing to 75:25, 50:50, and 25:75. The absorption peak position in carbonate mixtures is highly correlated with CaO contents(0.98~0.99). Based on color system, the carbonate rocks are grouped into (milky) white, light grey, light brown, grey, and dark grey. The absorption peak position shifts from 2340 nm to 2320 nm as CaO contents decrease from 55.86 wt.% to 29.71 wt.%. We confirmed that absorption peak position shifts depending on the amount of Ca, which is bonded to $CO{_3}^{-2}$, Mg, and Fe contents replacing Ca. This result suggests that CaO contents in carbonate rocks can be considered to quantitative analysis in the field by spectroscopic analysis.

• 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.

• The Journal of the Petrological Society of Korea
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• v.9 no.3
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• pp.187-203
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• 2000

Mafic microgranular enclaves (MME) occur in the granites from the Bohyunsan area. The host granites are generally of granodioritic and granitic compositions. The MME can be divided into magic mineral clusters, quartz diorite and diorite according to their occurrence. Halter variation diagrams show linear trends between the MME and the host granites. Though the rim compositions of plagioclase in the host granites and the MME are similar the core compositions of plagioclase in some host granites show abnormally high An content. The Mg/(Mg+Fe) ratio of hornblende in the host granites gradually increase from the core to the rim. The chemical composition of minerals in the host granites had been affected by more marc magma composition. The modelling of major elements of the MME and hybrid host granites also indicate that they result from simple mingling/mixing between a dioritic magma and the host granite magma. The MME are thus interpreted to be globules of a more mafic magma which intruded the granite magma. Partial equilibration has been achieved between the MME and the host granites after they were commingled with each other.