• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.25-32
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• 1998

To characterize the growth environment, inorganic composition and morphological chracteristics of leaves of Korean tea plant, soil and tea leaf samples were collected from 15 locations and analyzed. The chemical characteristics of soils were in range of pH 4.09~6.15, OM 23.9~72.6g/kg, available phosphate less than 300mg/kg, K $0.8{\sim}2.5cmol^+/kg$, Na $tr{\sim}0.17cmol^+/kg$, Ca $1.0{\sim}6.2cmol^+/kg$, and Mg $0.3{\sim}2.1cmol^+/kg$. The contents of Ni. Cr, Zn. Cu, Pb, and Cd were at the level less than natural content in upland soil. Most of the sample soils were sandy loamy and loamy texture. The native tea plants were mainly grown in bamboo thicket or in forest. The leaf sizes of tea plants were $6.85{\pm}1.75{\times}2.6{\pm}0.5cm$, lateral vein number $14.2{\pm}2.7$, and crenated number $58.5{\pm}11.2$, and the leaf color was thin to dark green. The contents of $NH_4{^+}$, $Na^+$, $K^+$, $Mg^{2+}$ and $Ca^{2+}$ in tea leaves were in range of 30.5~47.7, 45.5~164.5, 16,998~25,431, 1.590~2,392 and 1,085~1,958mg/kg, respectively. The contents of $F^-$, $Cl^-$, $NO_3{^-}$, $PO_4{^{3-}}$ and $SO_4{^{2-}}$ were in range of 21.2~63.2, 126.4~257.9, 108.5~185.9, 1,270~1.819, and $954{\sim}1,670mg/kg$, respectively. The leaf size of native tea plant grown widlly in Shunchun Changchun-ri, Hwasun Ssangbongsa, Kuryoi Chonunsa, Bosong Daewonsa and Namhae Boriam was as large as those of Yabukita. Japan cultiver, grown at Kangjin Jangwon tea field.

• The Journal of Engineering Geology
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• v.2 no.2
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• pp.173-200
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• 1992

The quality of groundwater in the central part of Taegu City is influenced by upstreams of Sin-stream and Beomeo-stream because the stream waters are main source of the groundwater, and chemical composition of the upstream waters has close relationship with andesite and monzonite in the igneous rock terrain. The pH of upstreams are weak acid ~ neutral in the igneous rock area and weak alkaline in the sedimentary rock area. Contents of $Ca^{2+}$ and $Mg^{2+}$ in the streams are apparently high, and $Na^{+}$ content is only slightly high in the sedimentary rock area. But $K^{+}$ content is lower in the Panyaweol formation area than in the monzonite area. The contents of heavy metals and $N0_3^{-}$ are also higher in the sedimentary rock area of residential sections and industrial complexes than those in the igneous rock area. The groundwater is contaminated in comparison to the upstream water of the igneous rock areas, and there are some differences in pollution level between the Panyaweol formation area of residential sections and the Haman formation area of industrial complexes. K, Na, Ca, Mg, Cl, $SO_4$ and $NO_3$ contents in the Haman formation area are relatively higher than those in the Panyaweol formation area. But pH is nearly equal in the two areas. The content of heavy metal ions is still lower than the drinking water standard of Korea and only slightly differs in the two sedimentary rock areas. But the groundwater in the Haman formation area is considerably contaminated by Kongdanstream and Dalseo-stream.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.351-355
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• 1999

In order to find anti-dementia drugs from natural products, prolyl endopeptidase inhibitors were purified from Puerariae Flos by consecutive solvent partition, followed by silica gel, Sephadex LH-20, and HPLC. Four isoflavonoid inhibitors were isolated and identified as tectorigenin, genistein, 5,7-dihydroxy-4',6-dimethoxyisoflavone, and 5-hydroxy-6,7,4'-trimethoxyisoflavone by means of instrumental analyses including $^{1}H-$, $^{13}C-$, $^{2}D-NMR$ and MS and $IC_{50}$ values against PEP were 5.30 ppm$(17.7\;{\mu}M)$, 10.39 ppm$(38.5\;{\mu}M)$, 13.92 ppm$(44.3\;{\mu}M)$, and 20.61 ppm$(62.8\;{\mu}M)$, respectively. Some previous mistakes in $^{13}C-NMR$ assignment were revised by careful investigation of HMBC and HMQC data.

• Journal of the Korean Wood Science and Technology
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• v.14 no.4
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• pp.40-46
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• 1986

Change of color of woods is a trouble frequently found in decorative wood products. In this paper, studies were carried out on discoloation sensitivities of wood specimens to iron (0.1%, $FeCl_3{\cdot}6H_2O$), alkali (pH12.0, NaOH), acid (pH 1.0 $C_2H_2O_4$) and exposing to sunlight (40 hrs.). Four soft-woods and eleven hard-woods grown in Korea were used in this test. The results obtained were as follows: 1. In iron stain, strong discolored wood species were Larix leptolepis, Quercus mongolica. Zelkova serrata and Prunus yedoensis, and light discolored were Paulownia lomentosa and Pinus rigida. 2. In alkali stain. light discolored wood species were Abies holophylla, Kalopanax pictum, Populus ${\times}$ albaglandulosa, Acer mono, Pinus rigida, Pinus densiflora, Quercus mongolica, Betula platyphylla var. japonica, Prunus yedoensis, Zelkova serrata, Populus euramericana, Pinus koraiensis and Paulownia tomentosa, but there was no wood species of strong discolored compared with the color difference values of other reports. 3. In acid stain, light discolored wood species were Pinus rigida, Paulownia tomentosa. Pinus koraiensis, Quercus mongolica, Kalopanax piclum and Acer mone, but there was no strong discolored species compared with the color difference values of other reports. 4. In exposing to sunlight, strong discolored species were Larix leptolepis, Acer mono, Paulownia tomentosa, Populus euramericana, Pinus densijlora, Robinia pseudoacacia, Abies holophylla, Populus ${\times}$ albaglandulosa, Zelkova serrata, Prunus yedoensis and Pinus rigida, and light discolored was Alnus japonica. In general, it was shown that Korean wood species were susceptible to change of color by exposing to sunlight and iron stain compared with by alkali stain and acid stain.

• Journal of Korean Society for Atmospheric Environment
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• v.26 no.6
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• pp.606-615
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• 2010

This study aims to identify the characteristics of soil in Mongolia, one of the major Asian dust sources that influence the Korean Peninsula. Soil particle size was analyzed and the result shows that sand (57.5~97.3%) was identified prominently in most regions, followed by silt (2.5~34.7%) and clay (0.0~7.8%). Soil pH of the covered regions were in the range 7.1~10.1, either weak alkaline or strong alkaline. Analysis of ion species in the soil samples exhibited that $Na^+$ ($91.9\;mg\;kg^{-1}$), $Cl^-$ ($65.9\;mg\;kg^{-1}$), and $Ca^{2+}$ ($53.5\;mg\;kg^{-1}$) were detected more in the soil than other species such as ${SO_4}^{2-}$ ($19.2\;mg\;kg^{-1}$), ${NO_3}^-$ ($46.6\;mg\;kg^{-1}$), ${NH_4}^+$ ($3.9\;mg\;kg^{-1}$), $K^+$ ($22.0\;mg\;kg^{-1}$), and $Mg^{2+}$ ($10.2\;mg\;kg^{-1}$). As for heavy metal content in the soil, concentrations of soil-borne metals including Fe, Al, Ca, Mg, and K tended to be high, while metals that come from manmade sources Pb, Cd, Cr, V, and Ni were remarkably low. The concentration of organic carbon (OC) was relatively high at $15.9\;{\mu}g\;mg^{-1}$, while elemental carbon (EC), directly released in the process of fossil fuel combustion, was not detected at all or found in very small amounts. The result indicates that pollution from manmade sources scarcely occurred. The analysis results from this study may contribute to improving modeling accuracy by providing input data for Asian dust prediction models, and be used as base data for determining the process of physiochemical transformation of Asian dust during long-range transport.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.252-257
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• 2001

To get the basic information for the water quality improvement and control of water resource at Mankyeong river stream, the water quality in four site of main stream and three site of branch stream at the upper stream were investigated mainly from February to August in 2000. The water temperature was affected by depth, flow rate of the water, and air temperature, and ranged 6.4 to $30.8^{\circ}C$. The pH, DO and BOD values of the water was $5.9{\sim}9.7$, $4.6{\sim}14.50\;mg/L$, and $0.1{\sim}11.8\;mg/L$ range, respectively. The content of total nitrogen, $NO_3-N$ and $NH_4-N$ was $1.19{\sim}10.61\;mg/L$, $1.00{\sim}5.93\;mg/L$, and ND $(non\;detected){\sim}2.79$ mg/L, respectively. The concentration of total phosphorus was ND to 1.14 mg/L. The concentration of Cl ion was $3.5{\sim}196.4\;mg/L$. The content of Fe and Mn was $0.002{\sim}0.100\;mg/L$ and $ND{\sim}0.04\;mg/L$, respectively. The contents of heavy metal Cd, Cu, and Zn were $ND{\sim}0.03\;mg/L$, $ND{\sim}0.05\;mg/L$, and $0.001{\sim}0.17\;mg/L$, respectively. Pb was not detected in all the samples. The pH, total nitrogen contents, and total phosphorus content were frequently exceeded the water quality standard for agriculture. The degree of water pollution was very varied by the sampling place. The water quality was generally polluted in the dry season more than in rainy season. The highest level of water pollution observed in the area of Samyea Bridge among the 7 sites.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.15-21
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• 2001

This study was conducted to investigate the immunomodulatory activities of proteoglycan extracted from cultured mycelia of Ganoderma lucidum IY009. The proteoglycan contained two polymer peaks, one was the higher MW peak of 2,000 kD and the other was low peaks of 12kD. To understand the part of strong pharmaceutical activity between two peak, the proteoglycan was separated by ultrafiltration and column chromatography and then examined the various pharmaceutical effects. High molecular weight fraction possesing high content of ${\beta}-linked$ glucan was exhibited high antitumor activity, against sarcoma 180 bearing ICR mouse. And also, anticomplementary activity was highly observed in high molecule fraction than low it fraction. When the raw 264.7 and murine peritoneal macrophage treated with low fraction, high fraction and other stimuli. The activities inducing tumor necrosis factor of the high factions were $2.2{\sim}2.5$ times stronger than that of low fraction.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.129-129
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• 2016

Graphene, as a single layer of $sp^2$-bonded carbon atoms packed into a 2D honeycomb crystal lattice, has attracted much attention due to its outstanding properties. In order to synthesize high quality graphene, transition metals, such as nickel and copper, have been widely employed as catalysts, which needs transfer to desired substrates for various applications. However, the transfer steps are not only complicated but also inevitably induce defects, impurities, wrinkles, and cracks of graphene. Furthermore, the direct synthesis of graphene on dielectric surfaces has still been a premature field for practical applications. Therefore, cost effective and concise methods for transfer-free graphene are essentially required for commercialization. Here, we report a facile transfer-free graphene synthesis method through nickel and carbon co-deposited layer. In order to fabricate 100 nm thick NiC layer on the top of $SiO_2/Si$ substrates, DC reactive magnetron sputtering was performed at a gas pressure of 2 mTorr with various Ar : $CH_4$ gas flow ratio and the 200 W DC input power was applied to a Ni target at room temperature. Then, the sample was annealed under 200 sccm Ar flow and pressure of 1 Torr at $1000^{\circ}C$ for 4 min employing a rapid thermal annealing (RTA) equipment. During the RTA process, the carbon atoms diffused through the NiC layer and deposited on both sides of the NiC layer to form graphene upon cooling. The remained NiC layer was removed by using a 0.5 M $FeCl_3$ aqueous solution, and graphene was then directly obtained on $SiO_2/Si$ without any transfer process. In order to confirm the quality of resulted graphene layer, Raman spectroscopy was implemented. Raman mapping revealed that the resulted graphene was at high quality with low degree of $sp^3$-type structural defects. Additionally, sheet resistance and transmittance of the produced graphene were analyzed by a four-point probe method and UV-vis spectroscopy, respectively. This facile non-transfer process would consequently facilitate the future graphene research and industrial applications.

• Economic and Environmental Geology
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• v.33 no.6
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• pp.505-517
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• 2000

This study was undertaken to provide a drinking water quality on the basis of physicochemical properties. In this study, the 25 samples of supply waters of the Taejon area were sampled twice (February and August in 1999). Hydrochemistry of the supply water belongs to the $Ca^{2＋}$-${HCO_3}^{-1}$ type, whereas the supply water was characterized by the relatively significant enrichment of ${Ca}^{2+}$, ${Na}^{2+}$, ${K}^{2+}$, ${Cl}^{2+}$ ions and heavy metals compared to the original water from the Daecheong lake. Generally, the supply water has a mean values for $10.7^{\circ}C$ of temperature, 6.86 of pH, -12 mV of Eh, 88 ${\mu}S$/cm of EC and 70.379 mg/l of TDS in February, whereas the waters of the same sites in August are a slightly high temperature ($26.1^{\circ}C$), TDS (78.069 mg/l) and extremely high EC (442 ${\mu}S$/cm) value. These values are similar with physicochemical properties of the original lake water depending on the seasonal differences. Results of speciation calculation indicate that potentially toxic ions might exist mainly in the forms of free metal (${Cu}^{2+}$ or ${Zn}^{2+}$) and a small amount of ${CO_3}^{2-}$and ${OH}^{-}$in the supply water. The water seemed to be in equilibrium with kaolinite field of the normal stability diagrams for the natural water. Based on enrichment parameter of the supply water normalized by original lake water composition, the average value of those parameter can be calculated with nearly 1.00, but the those values for Cu＋Zn possible source of decrepit pipe lines are 126.75 in February and 115.63 in August samples. The parameter values varied with sampling sites, however, do not exceed by chemistry of drinking water standard. Solid compounds remained on the membrane filter papers after filtration are adhered to pale yellow or yellowish brown colored dissolved solids and precipitates, which are coated by 0.02 to 0.35 mm thick per 500 ml with colloidal particles of about 1 to 2${\mu}m$ size. The particles are mainly Fe-Cu-Zn compounds and partly detected to Mn and Pb.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.357-365
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• 2002

A survey was under taken of six district of Northern India viz. Bareilly, Pilibhit, Udham Singh Nagar, Nainital, Almora and Rampur. The age, breed, sex and physiological status recorded. A total number of 854 cattle examined out of which lactating (274 cases), non lactating (302 cases) heifers (128 cases), calves (82 cases) and adult male (68 cases) were examined. An incidence of 4.92 percent (42) of microfilarisis was recorded. The highest prevalence was observed in Rudrapur District of Udham Singh Nagar (33.33%, 4/12), followed by Lalkaun in Nanital District (21.74%, 10/46), Rampur (12.50%, 2/16), Bareilly (8.16%, 8/98) and Pilibhit (1.22%, 1/82). No infection was observed in Almora region. Amongst 854 cattle of different group incidence was highest in adult male (12.20%, 10/82), followed by non lactating (3.82%, 12/314) and lactating (2.70%, 2/74), (7.64%, 12/157) was found in Heifers. For haemeto-biochemical, serum minerals estimations and therapeutic study 32 animals suffering from filariasis and 18 healthy animals were taken. 16 animals were treated with ivermectin $@200{\mu}g/kg $ body weight. Effect of this disease on production has also been estimated for which body weight and milk production was observed. The main clinical manifestations observed were anaemia, loss of appetite, debility, oedematous swelling especially in the abdominal region, increased heart rate, and respiration rate. Haematological changes indicated decrease in hemoglobin, total erythrocyte count, packed cell volume, erthrocyte fragility and neutrophil, whereas there was significant increase in erythrocytes sedimentation rate (ESR), total leukocyte count (TLC), lymphocyte and eosinophils. Biochemical changes showed significant reduction in the values of serum albumin, A : G ratio, where as there was significant increase in blood glucose, blood urea nitrogen (BUN), globulin, total lipid, total cholesterol, phospholipids, serum bilirubin. Serum mineral profile also altered markedly, which indicate a significant decrease in Ca, Cu, Fe, Zn, and Mn with increase value of Na and Cl. There was no significant change in P and K values. Enzyme pattern in micro filaria infected animal indicated increased level of AST, ALT, alkaline phosphatase, ornithine carbamyl transferase, sorbitol dehydrogenase, glutamate dehydrogenase, isocitric dehydrogenase and lactate dehydrogenase. In blood gas values and acid/base balance, there was an increase in $PVCo_2$ and $PVo_2$. It has been observed that microfilaria infected cattle showed decrease in body weight and milk production. Animal treated with ivermectin showed the return of these above values toward normalcy.