• Journal of the Korean Chemical Society
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• v.41 no.8
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• pp.385-391
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• 1997

Diffusion Coefficient$(D_0)$ and electrode reaction rate Constant$(K_0)$ of Co$(dimethyl bipyridine)_3(ClO_4)_2$ were determined by cyclic voltammetry and chronoamperometry. It was also investigated that the effects of solvent, concentration, and scan rate, etc. on the diffusion coefficient and the temperature effect on the rate constant. The peak currents and diffusion coefficients were dcreased as increasing the viscosity of solvent. Diffusion coefficient was $5.54{\times}10^{-6 }cm^2/sec$ and the reaction rate constant was $2.39{\times}10^{-3 }/s$ at 25$^{\circ}C$. The thermodynamic parameters such as ${\Delta}G^{\neq},\;{\Delta}H^{\neq},\;and\;{\Delta}S$ were calculated from plotting the reaction rate constants versus the solution temperatures. This compound was shown the catalytic effect on the oxygen reduction that the reduction peak current of oxygen was greatly enhanced and the peak potential was shifted to +0.2 volt.

• Clean Technology
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• v.24 no.1
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• pp.63-69
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• 2018

The reduction reaction characteristics and physicochemical properties were studied for the selection of oxygen carrier, which is the core of the chemical looping combustion (CLC) technology. Fuel conversion and $CO_2$ selectivity of oxygen carrier according to the concentration of reducing gas and the reduction temperature using three kinds of oxygen carrier (SDN70, N018-R2, N016-R4) were measured and compared. In addition, Attrition Index (AI) and BET surface area were measured to analyze the attrition resistance and the surface characteristics of the oxygen carrier. As a result, it was confirmed that all three kinds of oxygen carrier were suitable for use in chemical roofing combustion system, and the best particle was determined to be N016-R4.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.4
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• pp.35-41
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• 2020

The immobilization of the hydroxylamine-oxidoreductase on the water channel surface was performed to investigate the efficacy of ammonia removal in turbulent flow. The reaction by this enzyme proceeds rapidly by converting hydroxylamine into nitrous acid. For the analysis of the effect, a dimensionless mass transfer governing equation was established with the physical properties based on room temperature. The ammonia diffusion coefficient in water and the kinematic viscosity coefficient of water were 2.45×10-9 ㎡/s and 1×10-6 ㎡/s, respectively. The distribution of ammonia concentration in the water was calculated with respect to the distance from the point at which exposure to ammonia began. The quantitative distribution with respect to the mixing depth was also found. Such a quantitative analysis can provide insight into whether the enzyme immobilized on the water channel surface can be effectively used for ammonia removal.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.645-653
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• 2013

The results of examining total soluble solid, reducing sugar, antioxidant and sensory properties regarding LTD (Liriope Tuber Dried), LTSD (Liriope Tuber Steamed and Dried), LTASD (Liriope Tuber Alcohol-Steamed and Dried), LTDR (LTD Roasted), LTSDR (LTSD Roasted) and LTASDR (LTASD Roasted) are as follows : Total soluble solid content of the roasted samples (LTDR, LTSDR and LTASDR) was more than those of all dried samples (LTD, LTSD and LTASD). According to roasting conditions, total sugar and reducing sugar are significantly greater than the raw and dried sample (LTD) in all heat-treated samples. The browning index was significantly higher in all roasted samples. In particular, LTASDR had a high browning index. Further, the antioxidative activity of the roasted LT samples were higher than that of all dried LT samples. In particular, the LTASDR sample showed significantly high figures in DPPH scavenging activity, ABTS scavenging activity, Nitrite scavenging activity and xanthine oxidase inhibitory activity. Sensory properties showed an increased acceptance in all evaluation items among roasted samples. In this study, hot water extracts of steamed or alcohol-steamed roasted LT samples had a higher antioxidative effect than that of LTD or LTDR and attained positive results by getting high scores in the overall sensory evaluation. Therefore, when using Liriope tuber in making beverages or herbal recipes, it is appropriate to dry and roast before steaming or spreading with alcohol when treating LT.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.279-286
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• 2013

BACKGROUND: Soil incorporation of green manure crop(GMC) is one of the methods for reducing continuous cropping injury and increasing yield of carrot. The purpose of this study was to evaluate the effects of green manure crops on growth and yield of carrot for reduction of continuous cropping injury of carrot through crop rotation. METHODS AND RESULTS: To reduce the injury by continuous cropping system(CCS) of carrot cultivation, GMCs such as crotalaria and sudangrass were applied, which GMC was sowed in latter-June and returned to soil in latter-October. Nutrient contributions of N, $P_2O_5$, $K_2O$, CaO, and MgO in crotalaria were 8.3, 7.5, 4.4, 7.8, and 2.1 kg/10a, respectively. Nutrient contributions of N, $P_2O_5$, $K_2O$, CaO, and MgO in sudangrass were 8.4, 8.6, 26.8, 0.3, and 2.7 kg/10a, respectively. After incorporation of GMCs into soil, bulk density in soil with GMCs was lower than that in soil without GMCs(control). In soil after incorporation of GMCs, pH was not different in all treatment conditions, and ranged from 6.37~6.64. EC in soil after incorporation of GMCs was lower than that in soil without GMCs. The OM, T-N, and avail. $P_2O_5$ contents in soil with GMCs were higher than those in soil without GMCs. The growth and yields were increased as 39.2%(6,226 kg/10a) in the rotational cropping system(RCS) as compared to continuous cropping system(control and without NPK) of 4,473 kg/10a. Crotalaria cultivation were the most effective crop for reducing the injury of continuous cropping of carrot. CONCLUSION(S): This study suggest that the RCS using GMCs showed lower disease outbreak density in soil for carrot cultivation as compared to CCS without GMCs. Especially, the GMCs good effect for reduction of continuous cropping injury of carrot.

• The Korean Journal of Pharmacology
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• v.21 no.1
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• pp.62-77
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• 1985

In tile Iron-catalyzed Haber-Weiss reaction to produce OH., the requirement for $O^{-}_{2}{\cdot}$ is only to reduce $Fe^{+++}$. Possibly, the role of $O^{-}_{2}{\cdot}$ can be replaced by other reducing agents. Ascorbate is one of them in biological system. In the present study, the ability of ascorbate to produce $OH{\cdot}$ in the presence of $Fe^{++}$ and $H_2O_2$ was investigated by observing the degradation of hyaluronic acid and ethylene production from methional. Ascorbate stimulated the degradation of hyaluronic by $Fe^{++}$ and $H_2O_2$. That was confirmed by both viscosity change and gel-permeation chromatographic analysis. The observed degradation was almost completely prevented by catalase and $OH{\cdot}$ scavengers. In support of the above results, ascorbate enhanced the prouction of ethylene from methional in the presence of $Fe^{++}$ and $H_2O_2$. Other reducing agents (cysteine, glutathione, NADH and NADPH) showed similar activities to ascorbate in the degradation of hyaluronic acid and ethylene production. But no stimulatory effects were observed with their oxidized forms such as NAD and NADP. Thus, it appears that reduction of the metal ion was needed for $OH{\cdot}$ production. Among the metal ions tested, $Fe^{++}$ showed most potent catalytic action in the production of $OH{\cdot}$ The results obtained support that ascorbate can substitute $O^{-}_{2}{\cdot}$ in the metal-catalyzed reactions, particularly with $Fe^{++}$ by which $OH{\cdot}$ is produced with $H_2O_2$. The significance of the ascorbate-dependent production of $OH{\cdot}$ was considered with respect to possible role of ascorbate in the damage of inflamed joints.

• Journal of Life Science
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• v.22 no.5
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• pp.657-664
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• 2012

The aim of this study is to screen a therapeutic agent with a cognitive function. The inhibitory effect of $Curcuma$ $longa$ hot water extract (CLWE) on the angiotension-converting enzyme and acetylcholinesterase derived from rabbit lungs and neural cells (PC12), as well as its antioxidant effect, was investigated in this study. Thus, for the first time, the direct scavenging effect of CLWE on DPPH radicals, superoxide anions, hydroxyl radicals, lipid peroxidation, reducing power, and the protective effect of DNA oxidation related to oxidative stress was evaluated in vitro. In addition, it was observed that CLWE especially exhibited a scavenging effect on reducing power and superoxide anions in this study. CLWE showed a protective effect on DNA oxidation produced by hydroxyl radicals. Furthermore, CLWE inhibited the activity of angiotensin-converting enzymes above 0.25%. Additionally, the extract inhibited oxidative stress and inducible nitric oxide in neuronal cells. Therefore, these results demonstrated that CLWE has antioxidant activity and neuronal cell protective effects, suggesting that it may have great potential as a natural source for human health.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.132-132
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• 1993

정상세포의 암세포로의 전환에 수반하는 세포표면상에 당구조 변화가 주목을 받고 있으며 이에 탄수화물이 세포간의 상호작용, 성장 등에 중요한 역할을 하리라고 생각된다. 따라서, 당구조 변화를 야기 시키는 당분해소효소나 전이활성 효소의 활성이 주요한 임상적 지표가 될 수 있다. 또한 천연물에서 유래된 다당류 등이 면역증강 효과를 나타내면서 항종양 효과를 보여준다. 이와같은 일을 원활히 수행하기 위해서는 당을 분석하는 기술이 필요하다. 당을 분석하는 방법으로 많이 이용된 것 중의 하나가 유도체를 만들어 GC에 의해서 확인하는 것이고 또한 당은 chromophore가 없기 때문에 굴절율의 검출기를 이용한 HPLC에 의해서도 분석이 가능하다. HPLC에 의한 또 다른 방법으로 당의 환원당 말단에 형광기를 결합시켜 감도를 매우 높게하여 역상 칼람을 이용해 당을 분리할 수 있다. 환원당에 결합시킬 수 있는 물질로는 대부분 amine기를 띄고 있고 결합하여 형광을 나타내는 특징을 지니고 있다. 본 연구는 형광기를 결합시켜 전기영동과 HPLC에 의해 동시에 추적이 가능한 물질을 결합시켜서 분석을 용이하게 한 방법을 이용하여 단당류를 $C_{18}$ column에 의해서 분리하였고 또한 모델로서 면역증강제로 사용되는 운지버섯 및 영지버섯 다당류와 생약에서 분리한 지유의 당을 분석하였다. 현재까지의 결과로 가장 좋은 방법은 $C_{18}$-->phenyl column을 연결하여 isocratic 방법으로 분리하였을 때이었다. 버섯의 당은 대부분이 glucose로 이루어졌고 지유는 arabinose가 주 구성성분이었다. 위의 분석 기술을 이용하면 피코몰 범위내에서 정확한 구조를 가진 항암효과의 올리고당 및 암세포의 발현에 따른 당단백질의 당의 구조를 규명하는데 도움을 줄 수 있다.aeonol이 aspirin과 같거나 강한 사망 억제 효과가 있었다.cyclopropyl-7-(2-furanyl) -6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 4), 1-cyclopropyl-7-(2-thiophenyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 6) ,1-cyclopropyl-7-(3-pyridinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 8), 1-cyclopropyl-7-(2-fluoro-3-pyridinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid (compound 10)를 합성하였다.10^{－7}$ M)에 의한 단백인산화에 대하여는 더 미약한 억제-효과를 나타내었다. 이상의 결과는 PDE-1과 항우울약들의 항혈소판작용은 PKC-기질인 41-43 kD와 20 kD의 인산화를 억제함에 기인되는 것으로 사료된다.다. 것으로 사료된다.다.바와 같이 MCl에서 작은 Dv 값을 갖는데, 이것은 CdCl$_{4}$$^{2-}$ 착이온을 형성하거나 ZnCl$_{4}$$^{2-}$ , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서던지 NH$_{4}$$^{+}$의 경우 Dv값이 제일 작았다. 바. 본 연구의 목적중의 하나인

• Journal of Mushroom
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• v.17 no.3
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• pp.152-161
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• 2019

Phallus impudicus var. impudicus L. is an edible mushroom that has long been used as folk medicine in China. The aim of this study was to evaluate the antioxidant, anti-cholinesterase, and inflammation inhibitory activities of a methanol extract of fruiting bodies of P. impudicus var. impudicus L. The extract exhibited good 1,1-diphenyl-2-picrylhydrazyl scavenging activity, excellent ferrous ion chelating activity, and moderate hydroxyl radical scavenging activity compared with BHT at 2.0 mg/ml. However, the reducing power of the extract was significantly lower than that the BHT positive control. Although the inhibitory activities of methanol extract on acetylcholinesterase and butyryl cholinesterase were significantly lower than the galanthamine positive control at the concentration tested, the inhibition of acetylcholinesterase and butyryl cholinesterase was 52.83% and 55.17%, respectively, at 1.0 mg/ml. The methanol extract also demonstrated excellent inhibition of inflammation-related activities, such as production of nitric oxide in lipopolysaccharide-induced RAW 264.7 macrophage cells and acute edema induced by administration of carrageenan on the hind paw of rats. The collective results suggest that the fruiting body of P. impudicus var. impudicus L. might be a good source of antioxidant, anti-cholinesterase, and anti-inflammation compounds.

• Food Industry
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• s.172
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• pp.38-56
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• 2003

The volatile compounds of traditional Kyungsando squid sikhe were identified by GC-MS. the amount of-zingibirene among identified volatile compounds was 19.73 mg/kg. The major volatile compounds of sikhe was (Z)-Di-2-propenyl disulfide,-curcumene, methyl