• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.189-195
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• 2002

In order to elucidate the budget and cycling of Nitrogen and Sulfur, essential elements and principal constituents of acid rain, their input through precipitation, and their output by streamflow were quantified in coniferous and deciduous forested watersheds, using combination of nutrient concentration and hydrological analysis, in Kwangnung Experimental Forest from July 1991 to December 1993. Amount of annual mean precipitation was $12,916\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$, annual mean runoff $5,094\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$(39%), $7,467\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$(59%) in coniferous and deciduous forest watersheds, respectively. Amounts of annual input of $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ through preciptation were 12.5, $81.72\;kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, repectively. Annual output via runoff of $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ were 0.06, $39.23\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the coniferous forest watershed ecosystem, and 0.15, $55.46\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the deciduous one, respectively. On the basis of annual nutrient input and output, the annual budget of $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ were +12.46, $+42.49\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the coniferous forest watershed, and +11.35, $+26.26\;ton{\cdot}ha^{-1}{\cdot}yr^{-1}$ in the deciduous one. Thus $N({NO_3}^-+{NH_4}^+)$ and ${SO_4}^{2-}$ were accumulated in both forested watershed ecosystems.

• Korean Chemical Engineering Research
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• v.61 no.3
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• pp.426-438
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• 2023

Lithium-sulfur batteries, recently attracting attention as next-generation batteries, have high energy density but are limited in application due to sulfur's insulating properties, shuttle phenomenon, and volume expansion. This study used an economical and simple vacuum filtration method to prepare a freestanding electrode without a binder and collector. Carbon nanotubes (CNTs) are used to improve the electrical conductivity of sulfur, where CNT also acts as both collector and conductor. In addition, metal oxides (MO_x, M=Ni, Mg), which are easy to adsorb lithium polysulfide, are added to the CNT/S electrode to suppress the shuttle reaction in lithium-sulfur batteries, which is a result of suppressing the loss of active sulfur material due to the excellent adsorption of lithium polysulfide by metal oxides. The MO_x@CNT/S electrode exhibited higher capacity characteristics and cycle stability than the CNT/S electrode without metal oxides. Among the MO_x@CNT/S electrodes, the NiO@CNT/S electrode displayed a high discharge capacity of 780 mAh g^-1 at 1 C and an extreme capacity decrease to 134 mAh g^-1 after 200 cycles. Although the MgO@CNT/S electrode exhibited a low discharge rate of 544 mAh g^-1 in the initial cycle, it showed good cycle stability with 90% of capacity retention up to 200 cycles. Further, to achieve high capacity and cycle stability, the Ni_0.7Mg_0.3O@CNT/S electrode, mixed with Ni:Mg in the ratio of 0.7:0.3, manifested an initial discharge rate of 755 mAh g^-1 (1 C) and a capacity retention rate of more than 90% after 200 cycles. Therefore, applying binary metal oxides to CNT/S provides a freestanding electrode for developing economical and high-performance Li-S batteries, effectively improving lithium polysulfide's high capacity characteristics and dissolution.

• The Korean Journal of Mycology
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• v.41 no.4
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• pp.274-279
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• 2013

Slightly acidic hypochlorous water (SAHW) is well known for having a powerful and broad spectrum antimicrobial activity, and is harmless to the environment and humans. SAHW (pH 5~6.5, 20~30 ppm available chlorine concentration) was generated by electrolysis of dilute solution of HCl (4%) in a chamber of a non-membrane electrolytic cell. Our objective was to determine SAHW has a potential fungicidal activity on some phytopathogenic fungi. Spores of Botrytis cinerea, Colletotrichum acutatum and Phytophthora capsici were not culturable on agar media at approximately 10 seconds after treatment by SAHW. However, inactivation of Penicillium hirsutum was required over 3 min. Dilution of SAHW with sterilized distilled water (SDW) at the ratio of 1:1 (SAHW:SDW) against C. acutatum showed 100% inactivation but, the efficacy in 1:2 decreased until 63.2%. Control value of SAHW was 70.4% against C. acutatum on pepper fruits when applied upto 24 h postinoculation. SAHW has a powerful and wide spectrum antifungal activity and could be applied as a potential alternative to fungicidal agent for control of plant disease.

• Journal of Ginseng Research
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• v.32 no.1
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• pp.39-47
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• 2008

UV irradiation causes skin-aging involving coarse wrinkles, thickening, dyspigmentation, and rough skin surface. These phenomena in complex skin tissue is controlled with receptor of cell surface growth factor and cytokine receptors. The activation of receptors induces multiple downstream signaling pathways including expression of MMPs (matrix metalloproteinases). This study was aimed to elucidate the mechanism for anti-wrinkle activity of Korean red ginseng, Torilis fructus and Corni fructus mixture (KTNG0345). In this animal study, we have investigated decreasing effects of Korean red ginseng mixture on MMP-3 synthesis through diminishing $TNF-{\alpha}$ signaling that express MMP-1, -3, and -9. c-Jun and c-fos as a component of transcription factor AP-1 (activator protein-1) were analyzed the expression level using real time PCR and western blotting. c-Jun was decreased dose dependent manner both gene and protein level where as cfos was not changed. In upstream, JNK and PAK was not changed, but p38 was decreased in down stream. MMP-3, final product in this pathway was significantly decreased in dose dependent manner. These results suggest that Korean red ginseng mixture have a anti-wrinkle activity through $TNF-{\alpha}$ mediated MMPs expression pathway.

• The Journal of Engineering Geology
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• v.13 no.1
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• pp.83-105
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• 2003

Geochemical studies on the alluvial aquifer system near the Nakdong River were carried out for the basic investigation of the estimation of artificial recharge for the river bank filtration. In-situ data do not show any distinct difference between the pumping well and river. Most of waters belong to $_3$ and Ca-$SO_4$ types and show high Mn concentration. In the borehole installed with Multi-Ca-HCOPacker (MP) system, Na, Ca, Mg, $HCO_3$ contents of the groundwater are increased with depth increasing. Cl and $SO_4$ contents of the groundwater show the lowest values at the bottom level (18m depth) and Mn content is very high at the middle level (13.5 m depth) of MP system. There is no distinct difference in the ${\delta}^{18}O$ and D values and tritium content between MP, borehole and surface water samples. The sulfur isotope data indicate that the possible sulfur source is dissolution of sulfate mineral from sedimentary rock. Strontium isotope ratio shows a little differences between the pumping well and observation borehole samples. Nitrogen isotope data indicate that the nitrogen of water samples is originated from fertilizer or organic materials.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.268-273
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• 2014

Experiments on carbonization were conducted using fish offal generated from fish market for the purpose of resource recycling. Elemental composition of fish offal and effect of carbonation temperature on the overall yield were investigated. Carbon and hydrogen contents of fish offal were 51.1% and 7.6%, respectively in view of elemental composition. Particularly, nitrogen and sulfur contents were as high as 9.8% and 1.0%, respectively. These values suggests that odor problem of fish offal can be serious. Comparing elemental composition of fish offal with other waste materials, it is thought that carbon and hydrogen contents are considerably high. These implies that thermal disposal will be the best option for final disposal method of fish offal. As a results of carbonization experiments on Mackerel, Hairtail, Croaker and mixed sample of Mackerel, Hairtail and Croaker, carbonization patterns were quite similar irrespective of fish species. Carbonization yield was varied significantly depending on carbonization temperature at the carbonization time of 5 minutes and 10 minutes. When the carbonization time was maintained longer than 30 minutes, yield variation depending on time variation at each temperature was insignificant. Thus, it can be concluded that effect of carbonization time on overall yield was minor when the carbonization time was maintained longer than 30 minutes. Primary vaporization in carbonization conducted at the temperature of $400^{\circ}C$ was minor. Thus, difference of yield between temperature of $500^{\circ}C$ and $400^{\circ}C$ was appeared greatly. It can be concluded that yield difference depending on carbonization temperature can be neglected if the carbonizing temperature exceed $600^{\circ}C$ and carbonizing time exceed 10 minutes at the same time.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.83-93
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• 2015

This study investigated genetic, mineralogical and spectral characteristics of oil shale and coal samples in Dundgobi area, Mongolia. Based the Rock/Eval and Total organic carbon (TOC) analysis, kerogen type, hydrogen quantity, thermal maturity and depositional environment were confirmed. Moreover, the mineral composition of oil shale and coal samples were analyzed by XRD and spectroscopy. The result of Rock Eval/TOC analysis revealed that the samples of Eedemt deposit are immature to mature source rocks with sufficient hydrocarbon potential, and the kerogen types were classified as Type I, Type II and Type III kerogen. On the other hand, the samples from Shine Us Khudag deposit were mature with good to very good hydrocarbon potential rocks where kengen types are defined as Type I, Type II/III and Type III kerogen. According to the carbon and sulfur contents, the depositional environment of the both sites were defined as a freshwater depositional environment. The XRD analysis revealed that the mineral composition of oil shale and coal samples were quartz, calcite, dolomite, illite, kaolinite, montmorillonite, anorthoclase, albite, microcline, orthoclase and analcime. The absorption features of oil shale samples were at 1412 nm and 1907 nm by clay minerals and water, 2206 nm by clay minerals of kaolinite and montmorillonite and 2306 nm by dolomite. It is considered that spectral characteristics on organic matter content test must be tested for oil shale exploration using remote sensing techniques.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.66-71
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• 2004

This study has been carried out to investigate effect of Rehmanniae Radix (RR) and pear phenolic compound (PC) on the hyperglycemic mice induced with streptozotocin (STZ). For this purpose, male mice were fed with a 0.2 mL RR extract (S group) and the pear PC (90 mg/kg/day) dissolved in a 0.2 mL RR extract (SPC group) while the control group received the same commercial diet for 6 weeks. The blood glucose contents were examined from tail vein blood once a week for 6 weeks. Samples of pancreas removed after the experimental period were processed for the immunohistochemical identification of $\beta$-cells. The levels of serum glucose were decreased significalntly (p<0.05) in the S and SPC groups compared with the control group. The BUN and creatinine levels were significantly (p<0.05) decreased in SPC group compared with the control group. Intraperitoneal glucose tolerance tests peformed at 24 hours before that period revealed that glucose tolerances in S and SPC group were ameliorated. Immunohistochemical analyses of the pancreases revealed that a lot of insulin- positive $\beta$-cells were contained in a Langerhas's islets of S and SPC groups compared with the control group, and the number of Langerhas's islets were significalntly increased in S (p<0.01) and SPC (p<0.05) groups. These results suggest that RR extract and pear PC could recover the damages induced by STZ in the hyperglycemic mice.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.528-534
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• 1992

Growth stimulatory material for lactic acid bacteria was extracted from radish and radish green juice and its growth stimulatory effect was tested. Dried methanol-precipitated growth stimulatory material was lightly grayish white powder, Its ash content is 44% and approximately 50% of the ash is sulfur. It has reddish brown color upon solubilization in water. The material had unchanged stimulatory effect when it was treated with proteinase or pectinase, or ashed. The growth stimulatory activity was dialyzable. The material was able to counteract the growth inhibitory effect of EDTA. When selected lactic acid bacteria were grown at $30^{\circ}C$ for 24 hours in peptone(0.5%)-yeast extract(0.5%)-glucose(2%) broth with and without 0.5% growth stimulatory material, the material stimulated the growth of Lactobacillus plantarum, L. fermentum, L. leichmanii, L. sake, L. brevis, L. acidophilus, L. casei, Pediococcus pentosaceus, Leuconostoc mesenteroides, Streptococcus faecalis, S. lactis, S. cremoris and S. thermophilus by 19, 1833, 133, 444, 840, 32, 14, 18, 6, 17, 4, 5 and 4 times, respectively.

• The Journal of Internal Korean Medicine
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• v.28 no.3
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• pp.409-420
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• 2007

Objectives : The purpose of this study was to identify the anti-tumor effects of realgar on various cancer cells through molecular biologic and cellular biologic methods. Materials & Methods : We used 5 kinds of cancer cell lines:stomach cancer cell (AGS), glioma cells (T98G, A172, SNU-489) and prostate cancer cells (LNCaP). We injected the boiled extract of realgar. $50{\mu}$g/ml and $100{\mu}$g/ml to culture media (ml) for 24 hours. We examined the morphological changes under an inverted microscope and a fluorescence microscope. We measured the suppressive effect on viability of 5 kinds of cancer cells via XTT assay. We examined the effect on the revelation of PARP cleavage, Bcl-2 protein and Bax protein by western blot analysis. Results : The extract of realgar caused markedly morphological changes on AGS, T98G, SNU-489, and LNCaP. All of them showed withdrawn and floating appearance. The suppressive effect on viability of AGS, T98G, A172, SNU-489, and LNCaP showed that each test group had more suppressive effect on viability of AGS, T98G, A172, SNU-489, and LNCaP than the control group, which was statistically significantly (p<0.01). The extract of realgar did not induce PARP cleavage in AGS, T98G, A 172, SNU-489, or LNCaP. In the revelation of protein related to apoptosis, the protein levels of Bcl-2 decreased and the protein levels of Bax increased in AGS, T98G, SNU-489, and LNCaP treated with realgar. The protein levels of Bcl-2 decreased and the protein levels of Bax did not change in A172 treated with realgar. Conclusions : This experiment showed that realgar has anti-tumor effect on stomach cancer cells (AGS), glioma cells (T98G, SNU-489L and prostate cancer cells (LNCaP)