• Natural Product Sciences
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• 제9권4호
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• pp.286-290
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• 2003

Ratanjot is attributed to eight species of Boraginacae species belonging to genera Alkanna, Arnebia, Maharanga and Onosma and regarded as one of the important herbal drugs of indigenous systems of medicine. The root and root stock, which form the actual drug, are considered to be an anthelmintic, antipyretic and antiseptic. They are also claimed to be useful in burn, eczema, wounds and eruptions, and used for treating the diseases of eyes, bronchitis, abdominal pains, itch, etc. Several workers reported that the Naphthaquinones (arnebins), the main active constituents of the drug, are responsible for its colour and therapeutic efficacy. It is claimed that the Arnebia nobilis was imported to India from Afghanistan but the red coloured roots resembling with A. nobilis were found to be gathered by local people for commercial purposes during the course of botanical surey of Himalayan region. Hence, it is decided to evaluate Arnebia nobilis pharmacognostically. The important macro-microscopic features of this species are roots 1-5 cm broad; outermost xylem with broad vessels and innermost with groups of radially arranged narrow vessels while the middle region occupied by alternate rings of clusters of broad and narrow vessels and presence of pith. Besides the percentage of arnebin-1, -3 and 4 are 9.37, 10.53 and 1.72 respectively.

• 동력기계공학회지
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• 제17권2호
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• pp.29-37
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• 2013

Compared to gasoline engines, diesel engines with a relatively simple ignition system are more advantageous in the application of biodeisel fuel to engine. Then in this study the comparative analysis on the spray characteristics and combustion emissions characteristic between the biodiesel(soybean oil) and diesel, the fuel for commercial diesel engine, was performed with common rail injection system. Injection pressure and ratio of biodiesel blended fuel were selected as main experimental variables. Consequently, it can be found that there is no significant difference in the macro characteristics of the spray behavior(spray penetration and spray angle) in response to change in the blend ratio of soybean oil and diesel at a fixed injection pressure, in particular, soot creation in combustion emissions in the region of low pressure was greatly affected by the blend ratio of soybean oil, however, the creation in the region of high pressure was almost unaffected by the blend ratio because of promoted atomization.

• 한국도로학회논문집
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• 제20권4호
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• pp.27-34
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• 2018

PURPOSES : The objective of this study is to evaluate the physical properties of recycled asphalt mixtures reinforced with glass fiber. METHODS : Firstly, mixing design was conducted on recycled asphalt mixture for use of 50% recycled aggregate. Various laboratory tests were performed on four types of recycled asphalt mixtures with different glass fiber content to evaluate the physical properties. The laboratory tests include indirect tensile strength test, dynamic modulus test, Hamburg wheel tracking test and tensile-strength ratio to evaluate cracks, rutting and moisture resistance of mixtures. RESULTS : The indirect tensile strength of fiber reinforced glass increased about 139.4%. As a result of comparing the master curves obtained by the dynamic modulus test, the elasticity was low in the low temperature region and high in the high temperature region when the glass fiber was reinforced. The glass fiber contents of PEGS 0.3%, Micro PPGF 0.1% and Macro PPGF 0.3% showed the highest moisture resistance and rutting resistance. CONCLUSIONS : The test results show that use of glass fiber reinforcement can increase the resistance to cracking, rutting, and moisture damage of asphalt mixtures. It is also necessary to validate the long-term performance of recycled asphalt mixtures with glass fiber using full scale pavement testing and field trial construction.

• 폴리머
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• 제26권6호
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• pp.821-828
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• 2002

미량의 Pluronics가 첨가된 PLLA/l,4-dioxane/water의 삼성분계상을 온도 변화로 유도된상 분리법을 이용하여 10~300 $\mu\textrm{m}$의 공극 크기를 가지며 공극 간의 연결성이 우수한 PLLA 다공성 지지체를 제조하였다. 순수한 PLLA 용액에 Pluronics를 첨가하면 상 분리 온도가 P-123< F-68< F-127 순서로 순차적으로 상승한다. 이는 Pluronics의 양 말단 사슬인 PEO의 영향으로 상분리 진행이 촉진되기 때문이다. 상 분리 온도의 상승으로 스피노달 영역을 증가시켜 높은 온도에서 상 분리 유도가 가능하게 된다. 또한 상 분리 진행 시간 동안에는 계면에 흡수된 Pluronics가 거대 구조를 안정화시켜 상 분리 진행 속도를 지연시키게 된다.

• Journal of Species Research
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• 제13권1호
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• pp.67-88
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• 2024

Macrofungi are essential decomposers in the forest environment. Although more than 70% of the land is mountainous, there has been a lack of research on mushroom diversity in Korea compared to the global species estimation. For this reason, the need for further research became apparent. The surveys were conducted from 2014 to 2022 nationwide. As a result, 15 unrecorded macrofungal species were discovered: Agaricus thiersii, Baorangia alexandri, Boletellus putuoensis, Entoloma bulakhae, Entoloma pygmaeopapillatum, Entoloma subtenuicystidiatum, Gerronema kuruvense, Hyphoderma nudicephalum, Hyphoderma tenue, Macrolepiota subcitrophylla, Mycena jingyinga, Mycena yuezhuoi, Ophiocordyceps vespulae, Scytinostroma acystidiatum, and Steccherinum straminellum. These species are identified based on morphological, molecular, and phylogenetic analyses using the internal transcribed spacer (ITS) region and the nuclear large subunit rRNA (LSU) region. Here, we provided macro- and micro-morphological figures with phylogenetic trees to support 15 species as unrecorded to Korea.

• 한국자동차공학회논문집
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• 제9권3호
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• pp.18-26
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• 2001

This paper is the third of 3 companion papers which investigate axial stratification process. In-cylinder fuel behavior has been investigated in the port injected SI engine by visualizing for the purpose of understanding stratification. Planar laser light sheet from an Nd:YAG laser has been illuminated through the transparent quartz cylinder of the single cylinder optical engine and the Mie scattered light has been captured through the quartz window in the piston head with an ICCD camera. Fuel has been replaced with an air-ethanol mixture to utilize atomized fuel spray for the visualization purposes. This results have been compared with steady flow concentration measurement. In high swirl port, the most fuel remains at combustion chamber and upper cylinder region without being affected by injection timing. The macro-distributed state is not changed but the difference of the amount of fuel around the spark plug varies according to injection timing, which determines LML.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.105-108
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• 1996

We have studied the anisotropic dispersion force effects for surfaces alignment of liquid crystals (LCs) on rubbed polystyrene (PS) surfaces by unidirection. In microphotographs of the textures, we obtained the nematic (N) LCs are shown to align in both direction parallel and Perpendicular to the rubbing for region up to medium rubbing, however to align in the direction perpendicular to the rubbing for strong rubbing legion. We suggest that the anisotropic dispersion force is very important rather than macro-surface groove effect to uniform alignment of LCs. We also measured the temperature dependence of extrapolation length of 5CB on rubbed PS surfaces for strong rubbing. It is shown that the polar anchoring strength of 5CB is very weak on rubbed PS surface compared to the rubbed polyimide (Pl) surface.

• 지역연구
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• 제15권2호
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• pp.75-102
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• 1999

This paper attempts at analyzing the urban dynamics in Northeast Asia by looking at major forces transforming the regional structure of Northeast Asia. Trade and foreign direct invest-ment are identified as two principal channels of increasing economic interdependence in the region. In addition, macro development strategy and infrastructure policy are another set of determining factors for changes in the regional structure of Northeast Asia. To examine the role of cities and inter-city linkages, the paper first tries to identify major urban centers and urban hierarchy in Northeast Asia. Secondly, it examines the prospects for inter-city network formation. Against these anticipated changes in the regional structure and inter-city networks in Northeast Asia, the paper discusses about the future of Korea as well as the role of Koran cities in the regional economy of Northeast Asia.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제32회 KOSCO SYMPOSIUM 논문집
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• pp.181-188
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• 2006

Operation parameters for large scale industrial facility such as iron making plant are carefully selected through elaborate tests and monitoring rather than through a mathematical modeling. One of the recent progresses for better energy utilization in iron ore sintering process is the distribution pattern of fuel inside a macro particle which is formed with fines of iron ore, coke and limestone. Results of model tests which have been used as a basis for the improved operation in the field are introduced and a theoretical modeling study is presented to supplement the experiment-based approach with fundamental arguments of physical modeling, which enables predictive computation beyond the limited region of tests and adjustment. A single fuel particle model along with one-dimensional bed combustion model of solid particles are utilized, and thermal processes of combustion and heat transfer are found to be dominant consideration in the discussions of productivity and energy utilization in the sintering process.

• 한국잠사곤충학회지
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• 제40권2호
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• pp.169-175
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• 1998

The morphology of silk fibroin/poly(vinyl alcohol)(PVA)blend films was investigated using optical microscopy and confocal laser scanning microscopy. The effects of blend ratio and molecular weight of silk fibroin and PVA on phase separation were studied. Macro-phase separation occurred for the silk fibroin-rich/poor region whereas micro-phase separation took place for the dispersed/continuous phase, In spite of differences in molecular weight and blend ratio, it is observed that the dispersed phase and continuous one are composed of silk fibroin and PVA component, respectively. As the molecular weight of silk fibroin and silk fibroin content in blend ratio are decreased, the compatibility of blend is increased due to the reduction of micro-phase separation.