• Korean Journal of Soil Science and Fertilizer
• /
• v.27 no.3
• /
• pp.158-167
• /
• 1994

The various weathering products derived from andesitic rocks in the Guweol mountain area of Pusan have been studied in order to investigate the occurrence, characteristics and evolutional trend of clay minerals in the weathered rock and soil using mainly X-ray powder diffraction method. Kaolinite and halloysite are very abundant in the weathered rocks and soils derived from andesitic rocks of this area. Also, $12{\AA}$- and $14{\AA}$-minerals occur in the considerable amount. $12{\AA}$-minerals have been identified as mica/vermiculite interlayer minerals showing the $25{\AA}$ basal reflection. Their crystal sizes are relatively big showing more than 10 micron in diameter. Two types of $14{\AA}$-mineral, which are vermiculite/smectite interlayer mineral and Al-vermiculite, have been observed. Kaolin minerais consist of kaolinite, $10{\AA}$ and $7{\AA}$ halloysite. Kaolinite relatively dominates in the strongly weathered soil of the area. In contrast with kaolinite. $12{\AA}$- and $14{\AA}$-minerals such as vermiculite/smectite and mica/vermiculite interlayer minerals tend to occur in the weakly to intermediately weathered products. Based on their occurrences, it strongly suggests that they are intermediate products in the course of the weathering process from the parent materials into the kaolin mineral.

• Journal of Korean Society of Forest Science
• /
• v.89 no.4
• /
• pp.513-521
• /
• 2000

Red alder (Alnus rubra Bong.) seedlings inoculated with Frankia pure cultures were grown in a walk-in growth chamber for sixteen weeks. Half were inoculated with the spores of the ectomycorrhizal fungus Alpova diplophloeus (Zeller & Dodge) Trappe & Smith. The mycorrhizal seedlings were significantly larger than nonmycorrhizal plants in diameter, and nodule and shoot dry weight by 6 to 16% when their heights were very similar. The mycorrhizal effects on water relations of red alder seedlings were explored in a 30 hours water stress. Mycorrhizal and nonmycorrhizal seedlings did not significantly differ in leaf water potentials, $CO_2$ exchange rates or $N_2$-fixation rates during the drought. Our results suggests that A. diplophloeus mycorrhizas increased red alder seedling growth under well-watered conditions but do not affect water relations of the plant under water-stress.

• Journal of Conservation Science
• /
• v.8 no.1 s.11
• /
• pp.16-22
• /
• 1999

Species of 741 charcoal samples, which were excavated from the dwelling sites of the bronze age $(about\;2500\~3100\;B.P)$ at Hyeonwha-ri, Pyungteak, Korea, were identified. Most of samples were deciduous oaks (Quercus spp.; $97.7\%$) and others were alders (Ainus spp.; $1.9\%$) and soft pines (Pinus spp.; $0.4\%$). Tree rings of nine largest samples were also examined. The numbers of annual rings were 8 to 36 and mean ring width was rather narrow $(0.65\~1.82\;mm)$. Most samples possessed pith and tylosis. The results indicate that logs 10 to IS cm diameter had been used for the poles of houses without further processing.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.9 no.1
• /
• pp.45-50
• /
• 1980

Myofibrilar Protein from Korean Duck Muscle was extracted and ATPase activities were studied. The results were as follows: 1. Mg-activated ATPase activity of Myofibril from Korean Duck, muscle exhibited a biphasic response, ATPase activity was high at a low ionic strength and low activity was showed at high ionic strength. 2. Effect of EDTA on the Myofibrillar protein ATPase activity was studied, it was investigated that the EDTA inhibition was showed at the concentration of $6.9{\mu}g$ and it above. 3. It showed that the effect of Ca++ on ATPase activity was decreased at the lower than $3{\mu}g$. Inhibition showed at the concentration of $6.9{\mu}g$ and it above. 4. It showed that the effect of Mg++ on ATPase activity was decreased at the lower than $3.6{\mu}g$. Inhibition showed at the concentration of $3.9{\mu}g$ and it above.

• The Korean Journal of Pesticide Science
• /
• v.15 no.3
• /
• pp.231-237
• /
• 2011

Highly bio-active plant essential extracts and oils from pepper, clove bud, rosemary and origanum which are selected to develop environment-friendly insecticides was studied for their acute toxicity. The results of acute oral toxicity using rats showed $LD_{50}$ value of over 2,000 mg/kg bw for pepper, clove bud, rosemary and origanum oils. The calculated acute dermal $LD_{50}$ value of pepper was over 4,000 mg/kg bw and anther testing materials was over 4,000 mg/kg bw. The skin irritation test showed that pepper, clove bud and rosemary oils had no irritation while origanum oil had a moderate irritation. According to the eye irritation test, it showed that there was no irritation for pepper and rosemary oils, while there were irritation for clove bud and origanum oils. Consequently, pepper and rosemary oils were shown to be low in toxicity whereas clove bud oil was indicated to cause a mild eye irritability and origanum oil, causing a moderate skin and eye irritability.

• Journal of Life Science
• /
• v.29 no.12
• /
• pp.1386-1392
• /
• 2019

This study investigated the potential of dye plants as natural oral health products. The antibacterial activity of ethanol stem extracts of A. japonica, R. verniciflua Stokes, G. jasminoides, D. morbifera, P. amurense Rupr., and S. japonica against P. gingivalis KCTC 5352, S. mutans KCTC3065, S. downei KCTC3634, S. sanguinis KCTC3284, and S. gordonii KCTC 3286 was confirmed. Among the stem extracts from 6 dye plants grown in Korea, ethanol extract from A. japonica stem (1 mg/disc) showed the highest antibacterial activity against P. gingivalis KCTC5352. The A. japonica stem extracts showed antibacterial activity similar to chlorhexidine, which was used as a positive control. The MIC and MBC of P. gingivalis KCTC5352 were 0.4 mg/ml and 0.6 mg/ml, respectively. The biofilm production rate and cell growth of P. gingivalis KCTC5352 in the cultures treated with 0.2-2.0 mg/ml of A. japonica extract were significantly decreased in a concentration-dependent manner. In addition, the mRNA expression of the superoxide dismutase and fimA associated with fimbriae formation in these cultures was suppressed, also in a concentration-dependent manner. Based on these results, it is concluded that A. japonica stem extracts can be used as an oral health product derived from natural materials, as demonstrated by its antibacterial action against and inhibition of biofilm formation of P. gingivalis KCTC5352.

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2006.05a
• /
• pp.611-611
• /
• 2006

• The Science & Technology
• /
• no.12 s.415
• /
• pp.20-23
• /
• 2003

한국과학기술단체총연합회(회장 김시중)가 주최하고 한국경제신문사가 후원한 '국제 펨토포럼'이 지난 3일부터 5일까지 국내에서는 처음으로 제주 오리엔탈호텔에서 열렸다. 이번 행사에는 국내외 석학과 전문가 1백여 명이 참석, '펨토과학기술 - 미래와 전망'이란 주제로 연구성과 발표와 토론을 벌였다. 그 내용을 지상중계한다.

• 프린팅코리아
• /
• v.12 no.8
• /
• pp.88-89
• /
• 2013

인쇄품질을 관리하기 위해선 고려해야 할 점이 많다. 그 중에서도 컬러의 관리는 가장 까다로우면서도 중요한 문제다. 인쇄물의 첫인상을 전달하는 컬러는 가장 많은 논란의 대상이 되기도 한다. 이런 이유에서 컬러매니지먼트는 인쇄물 품질 관리의 핵심이자, 판단기준으로 여겨지고 있다. 엑스라이트, 엡손, 프레스사인, 잉크존, 오리스 등의 컬러매니지먼트 관련 차트, 솔루션, 계측 장비, 평가 툴 등의 제품과 솔루션을 공급하는 토털 서비스업체 (주)미디어머신(대표이사 장영엽)과 함께 하면, 컬러 관리의 답이 보인다.

• KASI NEWSLETTER
• /
• s.24
• /
• pp.1-4
• /
• 2000

신년사/소행성25개 무더기 발견/2001년 역서 및 천문력 발행/정책 간담회 개최/2001년도 기관고유사업 공개발표회 개최/2001년도 동계 교원 천문연수/충남대와 학연 석박사 과정 협약체결/제2회 한-일 과기포럼 참석/제2회 우주환경 워크샵 개최/콜로퀴움/오리온에서 다수의 미동정 분자선 발견