• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.3
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• pp.85-90
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• 2010

In this study, we have examined the monthly combustion characteristics of Quercus variabilis, a representing Quercus Spp. in Korea, using its living leaves over the period of from June to October. As a result, we were able to identify that their moisture content was about 114%~155%. The leaves of Quercus variabilis collected in October showed the lowest moisture content and nonflaming ignition temperature. The leaves of July showed the fastest flaming ignition time of 27s while those from September showed the longest persistence of flame with 105s, and also showed the highest total heat release amount. There was a noticeable difference in each month of the above period regarding total heat release amount and total smoke release amount with a gradual increase from June to October. The maximum smoke density was a bit higher in October leaves but there was no significant monthly difference. In addition, July leaves were shown to reach the maximum value in the shortest time of 795s.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.6
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• pp.602-606
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• 1994

The study was conducted to investigate the relationships between the value of fresh leaf lengh ${\times}$ width and actual fresh or cured leaf area, Cured leaf weight of cutter and leaf in Burley tobacco plants. In all tested varieties, Actual fresh leaf area or cured leaf area, cured leaf weight was high significantly correlated with the value of fresh leaf length ${\times}$ width. The linear regression equation between them could be exploited for rapid and easy estimation of either fresh or cured leaf area, cured leaf weight. Highly significant correlation between fresh leaf area and cured leaf area or cured leaf weight was confirmed and a linear regression equation was also obtained for easy estimation of cured leaf area or cured leaf weight.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.99-104
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• 1983

Chemical changes of major tea constituents by tea manufacture were examined by the quantitative masurements of tannin, caffeine, free sugars and total amino acid. The sample used in this experiments was fresh green and black tea leaves, green tea prepared by classical panning process and black tea prepared by commercial process. The results obtained are as follows: Compared with fresh tea leaves, tannin was increased 2% in green tea and decreased 56.5% in black tea by tea manufacture. Caffeine was increased 25.9% in green tea and decreased 3.1% in black tea. Total free sugars were decreased 78.2% and 76.7% in green tea and black tea, respectively. Total amino acids were decreased 26.1% and 18.8% in green tea and black tea, respectively.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.362-365
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• 2010

본 연구에서는 소나무와 굴참나무의 생엽을 대상으로 기후변화에 따른 연소특성을 분석하고자 월별 기온 및 습도 등과 같은 기상조건별 연소특성을 비교하는 연구를 수행하였다. 소나무의 경우, 연중 내내 생엽의 채취가 가능하지만 굴참나무의 경우에는 생엽 채취가 가능한 6월부터 10월까지를 실험 대상으로 선정하였다. 기상조건은 각 시료별 생엽을 채취한 일자의 기상청 발표 자료를 적용하였으며, 연소특성분석은 콘칼로리미터, 연기밀도시험기, 발화점시험기 등과 같은 장비들을 활용하였다. 분석결과로는 열방출량을 비롯하여, 연기방출량, 함수율, 발화점 등을 측정하여 비교하였다.

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.160.2-160.2
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• 2009

• 한국방재학회:학술대회논문집
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• 2009.02b
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• pp.161.1-161.1
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• 2009

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.548-556
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• 2009

본 연구에서는 산불발생 시 삼림 내 가연물의 화재강도 및 산불위험성을 예측하기 위하여 영동지역에서 자생하는 관목류 가운데 주요 분포수종으로 생강나무와 초피나무를 대상으로 생엽과 가지부위를 채취하여 착화특성, 화재전파특성, 피난특성을 고찰하였다. 발화온도 범위는 400$^{\circ}C$${\sim}$440$^{\circ}C$로 확인되었으며 생강나무의 생엽은 착화가 가장 빠르게 개시되었으며 가지부위는 생엽보다 착화는 늦으나 착화 후 화염유지시간이 길고 비교적 빠른시간에 많은 열량을 방출하는 것으로 나타났으며 초피나무의 가지부위는 연기방출량과 CO 및 $CO_2$의 방출량이 많은 것을 확인할 수 있었다.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.39-42
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• 2012

A new method for the high throughput screening of antagonistic substances against rice pathogens using rice leaf explants was developed. This method can be used to confirm the activities of any compound or mixture suppressing rice bacterial blight (BB) before field tests. Xanthomonas oryzae pv. oryzae (Xoo) culture medium was distributed in 96 well plates with equally sized explants and the active compounds were added to the wells. The strength suppressing BB was converted into an area percent of the lesion on the rice explants. The explants under BB suppressing activity remained uninfected maintaining their actual green color, while infected explants exhibited pale yellow-colored lesions. Based on the results, this method seems to be faster and easier, dose-dependent, and can be performed all-at-once with a small amount of unspecified compounds. This method also has the potential to be applied to inspection activities for the suppression of other waterborne crop diseases.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.436-440
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• 2011

본 연구는 산불발생에 따른 온실가스 배출량 추정을 위한 기초 data 제공에 주안점을 두고 산림연료를 대상으로 연소실험을 수행하였다. 연료의 대상은 참나무(굴참, 떡갈, 신갈, 갈참, 졸참, 상수리)를 대상으로 부위별(생엽, 가지, 수피) 채취하여 사용하였으며, 콘칼로리미터를 이용하여 $CO_2$ 배출량을 분석하였다. 중량 50g의 연료 기준에 대한 $CO_2$ 배출량은 생엽 42.38~95.41g, 가지 82.92~113.10g, 수피 72.64~100.70g 정도 범위에서 $CO_2$를 배출하는 것으로 나타났다. 부위별 평균배출량을 살펴보면, 생엽 72.10g, 가지 101.88, 수피 86.46g 정도의 값을 보여 가지부위가 가장 많은 $CO_2$를 배출하는 것을 알 수 있었으며, 또한, $CO_2$를 상대적으로 많이 배출한 수종으로는 상수리나무인 것으로 나타났다.

• Fire Science and Engineering
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• v.23 no.1
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• pp.21-32
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• 2009

In order to inspect the danger of forest fires, the thermal characteristics and the ignitability of the dead leaves and the living leaves for the main species of trees in Youngdong areas have been studied by the TG/DTA and the group flammability tester. From this work, the thermal delay has been increased with the increase of the heating rate. The fractions of the thermal weight loss for the dead leaves and the living leaves of the coniferous trees were higher than those of the broadleaf trees. Also, it was confirmed that the ignitable dangers of the dead leaves and the coniferous trees were higher than those of the living leaves and the broadleaf trees, due to the low auto ignition temperature and thermal resistance.