• The Korean Journal of Ecology
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• v.24 no.3
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• pp.137-140
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• 2001

The antifungal activity of chemical substances from Artemisia annua were examined. Antifungal activity of aqueous extracts from A. annua was higher than that of essential oils in Fusarium oxysporum, whereas that of essential oil was higher than that of aqueous extracts in Aspergillus nidulans. The GC/MS methods were employed for the analysis and identification of phytotoxic substances from A. annua. Essential oil of some components were identified including thujone, terpineol, β-pinene, cienole, 2,4-hexndienal, camphor, citronellal, (-)-menthone, (1R)-(-)myrtenol, (S)-(-)-perilla aldehyde, perilla alcohol, 4-tert-buthylaniline, eugenol, isosafrole, isoeugenol and α-humulene. These results suggest that the chemical substances from A. annua such as terphenoids seem to be responsible for the allelopathic effect.

• Analytical Science and Technology
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• v.22 no.1
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• pp.65-74
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• 2009

Active components of lacquer tree referred to as urushiol congeners, which are catechol derivatives with various alkyl or alkenyl substituents. The olefin side chains typically have one, two or three double bonds. In this study, the each congener's ratio analysis of extracts from korean lacquer tree are compared to the one from other asian lacquer tree. Extraction was performed using liquid-liquid extraction (LLE) method with soxhlet system from tree's bark and sap. Extracts were analyzed by reverse phase liquid chromatography and on-line electro spray ionization mass spectrometry (LC-MS/MS).

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1988.06a
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• pp.43-48
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• 1988

보호피막을 입히는 방법으로는 화학증착법과 물리증착법이 주로 사용되고 있다. 고온 분위기에서 기체 상태인 반응물의 화학반응을 통하여 원하는 물질을 증착시키는 화학증착법은 물리증착법에 비해 점착성(adhesion)이 우수하고, 보호피막층의 성분조절이 용이하며, 반응물이 기체상태이므로 대량생산이 용이하여 보호피막 증착법으로 많이 사용되고 있다. $Si_3N_4$-TiC ceramic 표면에 TiC, TiN 및 Ti(C, N) coating을 함으로써 얻을 수 잇는 장점들은 표면층의 경도를 증가시키며, steel과의 마찰계수의 감소 및 coating 층 자체가 고온에서 고체 윤활제로 작용하여 마찰열의 상당한 감소를 얻을 수 있으며, 또한 coating층 자체가 비교적 안정한 화합물로 피삭재내의 성분원소들에 대한 diffusion barrier로 작용되며, 내식성을 증가시킬 수 있다. 본 연구에서는 각 증착층의 미소경도, 열충격저항, steel과의 마찰계수를 측정하였으며, 최종적으로 절삭시험을 통하여 증착층들의 내마모성을 조사, 규명하였다.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05a
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• pp.980-986
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• 1995

LOMI(Low Oxidation State Metal Ion) 재염제의 구성성분 중 가장 중요한 성분인 $V^{2+}$-formate 를 formic acid 내에서 VO$^{2+}$ 이온을 전기화학적으로 환원시켜 제조하였다. 산성용액 내에서의 전기화학반응은 목적반응인 바나듐이온의 환원반응과 부반응인 수소이온의 환원반응이 경쟁적으로 일어나며 이는 전극재료의 영향을 크게 받는다. 따라서 본 연구에서는 Cyclic Voltammetry(CV) 방법으로 여러 가지 전극재료의 특성을 조사하여 공업적 활용이 가능한 전극으로 수은, 납 및 스테인레스 스틸을 선정하였다. 선정된 전극을 이용하여 제조실증시험을 수행한 결과 소량의 고순도 제염제의 제조에는 수은전극을 대략의 공업용 제염제가 필요한 경우에는 스태인레스 스틸 전극을 음극재료로 사용하는 것이 효과적임을 알 수 있었다.

• Journal of the Korean Wood Science and Technology
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• v.31 no.2
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• pp.24-30
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• 2003

Three nucleotides, one amide, acid and steroid, were isolated from the fruit bodies of Lentinula edodes. The structures were determined as adenosine (9-𝛽-D-ribofuranosyladenine), uridine (1-𝛽-D-ribofuranosyluracil), uracil (2, 4-pyrimidinedione), nicotinamide, p-hydroxybenzoic acid and ergosterol (ergosta-5, 7, 22-triene-3𝛽-ol), respectively, on the basis of spectroscopic data and chemical correlations.

• Korean Journal of Organic Agriculture
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• v.8 no.3
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• pp.131-146
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• 2000

This experiment was focused on finding out the potential problems in organic farming system, which is recently emphasized on the produce of horticultural crops due to the serious environmental deterioration. Thus, in this study, the effect of the application of organic farming materials in soil on plant growth and components of chinese cabbage and the soil Physicochemistry property were compared with conventional culture. The results were summarized as follows : 1. The effect of soil chemical properties after application of organic farming materials, The amounts of pH and O.,M. in N, P, K treated plot were few of change, To the contray, fermentation compost and microorganisms fermentation compost treated plot were some increase, Amount of P$_2$O$_{5}$ , Ca and increase in comparison with the N, P, K treated plot, Specially chicken manure+ microorganisms fermentation compost treated plot was the highest. 2. Change of soil microbial after application of organic farming materials, The number of bacteria and actinomycetes in N, P, K treated plot were appeared definite direction, to the fermentation compost and microorganisms fermentation compost treated plot showed the increased tendency, specially, chicken manure+ microorganisms fermentation compost treated plot was the highest, 3. The growth characteristic of chinese cabbage after application of organic farming materials was superior in order of chemical fertilizers plot> microorganisms fermentation compost plot> fermentation compost plot. It shows the NO$_3$$^{[-10]}$ accumulation in chinese cabbage was higher in the outer leaves than in the inner leavess. It was some lower in the microorganisms fermentation compost plot, it was the highest at chemical fertilizers plot , all inner and outer leaves.

• 정보보호뉴스
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• s.128
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• pp.24-25
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• 2008

기자의 학창시절 중 가장 큰 고통(?)을 안겨 준 수업 시간은 화학시간이었다. 눈에는 보이지 않는, 하지만 여러 개의 분자와 원자로 구성된 성분을 어떻게 구분해야할지, 또 눈에 보이지 않는 성분이 도무지 이해되지 않았던 탓이었다. 악성코드나 웜.바이러스를 대하는 일반인들의 심정도 그러하지 않았을까. 같아 보이지만 서로 다른 악성코드와 웜.바이러스. 분석대응팀은 그 미세한 차이를 구별하고 분석하는 일을 한다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.320-321
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• 2003

대기중에 존재하는 입자상물질은 광범위한 입경역에 걸쳐서 다종다양한 미량화학성분으로 구성되는 분산체이고, 그 성상은 공간적으로도 시간적으로도 크게 변동한다. 입자상 물질의 화학분석법은 발생원 동정을 위한 자료로 적합하며 일반적으로는 습식의 파괴적인 원소분석으로 하는 경우가 많다. 일반적으로 화학적 분석법은 개별입자의 정보가 무시되며 필터에 포집된 bulk 시료에 의한 분석이 진행되므로 장시간 포집에 의한 단시간의 시간변동과 개개의 입자가 가지는 정보가 무시되고 평균화 되어버린다. (중략)

• Journal of the Korean Chemical Society
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• v.13 no.4
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• pp.263-272
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• 1969

액체의 상태합을 유도하여 여러 가지 액체들의 적용하여 열역학적 성질들과 점성도를 계산하여여 측정치와의 좋은 일치를 보았다. 그리고 이 상태합을 써서 여러 성분으로 된 액체 용액의 상태합을 얻었으며 나아가서 액체 용액에서의 화학 반응 속도를 구할 수 있음을 보았다.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.73-78
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• 2011

This study was conducted to evaluate the effect of developed SCB (DSCB) liquid fertilizer produced by adding N, P and K at SCB liquid fertilizer on the growth of kentucky bluegrass. Two different N sources used in DSCB were ammonium sulfate (DSCB-A) and urea (DSCB-U), respectively. Fertilizer treatments were designed as follows; non-fertilizer (NF), control (CF; chemical fertilizer), DSCB-A1 ($200\;ml{\cdot}m^{-2}$DSCB-A), OSCB-A2 ($250\;ml{\cdot}m^{-2}$DSCB-A), OSCB-U ($250\;ml{\cdot}m^{-2}$DSCB-U) and CF+SCB (CF+$250\;ml{\cdot}m^{-2}$SCB). Every treatment was arranged in a randomized complete block design with three replications. In kentucky bluegrass, turf color index, chlorophyll index, dry weight and nutrient contents were measured. Results were as follows; It was hardly affected by DSCB and SCB application in investigation of chemical properties of soil. Turf color index and chlorophyll index in DSCB and SCB treatments were increased by 1~2% and 19~24% than NF, respectively and similar to CF. As applied with DSCB and SCB, dry weight of DSCB-U and CF+SCB was increased by 36% and 10% than CF, respectively, but similar to that of OSCB-A1 and DSCB-A2. Evaluated with turf quality and growth, DSCB-U was the best in all treatment and OSCB-A1 the most efficient. These results indicated that applications of OSCB and SCB promoted turf quality and growth of kentucky bluegrass or similar to CF, so that they were expected to replace chemical fertilizers.