• 천문학회지
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• 제19권1호
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• pp.1-9
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• 1986

We present a method for deriving most optimal filter system by which the accuracy of derived physical quantities can be maximized. Using Kurucz(1978)'s model atmospheres, an optimal four filter system for F and G dwarfs is suggested, for which mean wavelengths are located at $3400{\AA}$, $3850{\AA}$, $4190{\AA}$, and $4600{\AA}$ with half-bandwidth of $200{\AA}$. It is found that 35, 38 and 42 filters of the DDO system and the $Str{\ddot{o}}mgren$ u and $\nu$ filters are close to those of the most optimal system.

• 한국식품과학회지
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• 제48권3호
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• pp.296-300
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• 2016

The effect of different temperatures (45, 55, 65, and $75^{\circ}C$) on the extraction of ${\beta}$-glucan and the properties of extracted ${\beta}$-glucan were investigated with four different varieties of barley. Jeju naked barley, blue barley, beer barley, and black barley contained 6.85, 5.13, 3.58, and 4.16% of ${\beta}$-glucan, respectively. ${\beta}$-glucan in barley was extracted in the range of 64.88 to 93.84% depending on the extraction temperature and barley variety. The ${\beta}$-glucans in Jeju naked barley, Jeju blue barley, and black barley were optimally extracted at $65^{\circ}C$ for 3 h and Jeju beer barley at $75^{\circ}C$. The extracted ${\beta}$-glucan resolubilized to 43.48-81.73% and the ratio of ${\beta}(1{\rightarrow}3)$ to ${\beta}(1{\rightarrow}4)$ linkage was in the range of 1:3.8-5.8. These results suggest that purification and properties of ${\beta}$-glucan depend not only on the water extraction temperature, but also on the barley variety.