• Title/Summary/Keyword: Natural park

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Cirsiumaldehyde from Gastrodia elata

  • YunChoi, Hye-Sook;Pyo, Mi-Kyung;Park, Kyung-Mi
    • Natural Product Sciences
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    • v.3 no.2
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    • pp.104-105
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    • 1997

  • In the course of continous work on tubers of Gastrodia elata, a new constituent was isolated from the ethyl acetate soluble fraction prepared from the methanol extract. The structure of the compound was identified as ${\alpha},{\alpha}'-[bis-2-(5-carboxaldehydo)furanyl]-dimethyl$ ether from the elemental analytical and spectroscopic data. This compound was once isolated from Cirsium chlorolepis and named as cirsiumaldehyde. This is the first furan type compound isolated from Gastrodia elata.

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Composition-Dependent Properties of Natural Rubber Blended with Butadiene Rubber (배합비에 의한 고무 블렌드의 물성변화)

  • Kwon, Kih-Wan;Park, Moon-Soo
    • Elastomers and Composites
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    • v.31 no.5
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    • pp.347-352
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    • 1996

  • A natural rubber was blended with a butadiene rubber with different ratios. A natural rubber, along with three different blends, its ratio varying from 10 to 15 to 20 weight %, were prepared and tested. It was found that inclusion of the butadiene rubber increased cure time, compared to the natural rubber. It is speculated that increased free volume due to the inclusion of butadiene rubber contributed to this effect. Furthermore, inclusion of butadiene rubber led to increase hardness of a sphere, and as a result, the extent of rebound increased sharply.

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