• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.789-790
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• 2001

• Bulletin of the Korean Chemical Society
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• v.19 no.3
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• pp.379-383
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• 1998

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.519-522
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• 2001

• Proceedings of the Korean Society of Rheology Conference
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• 2001.09a
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• pp.152.3-152
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• 2001

(No abstract, see full-text)

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.265-266
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• 2006

The chemical conversion coating formed on magnesium alloy investigated for low cost and harmless in environment by using the colloidal silica as the main component. The film formed in 298 K is thick, the film, which was thought combination of Si-O, was formed. The film formed in 313 K is thinner than that in 298 K. The quantity of film formed at high temperature such as 333 K and 353 K is smaller than dissolved quantity. At the anodic polarization experiment, corrosion resistance in sealing by hot water after chemical conversion treatment in basic solution condition get worse than that in comparison with basic solution condition. In salt spray test, the ratio of black rust on specimen that did not conducted chemical conversion treatment was five times or more compared with those of chemical conversion treated specimen. The film thickness of chemical conversion coating produced by alkali treatment process is thinner than in comparison with that of specimen produced in basic chemical conversion treatment solution condition. It is thought, however, that it showed good corrosion resistance during salt spray test because the area of microcracks is small.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.199-204
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• 1998

This study was conducted to investigate the chromosomal locations and effects of quantitative trait loci (QTL) associated with chemical properties of rice (Oryza sativa L.). One hundred sixty four recombinant inbred lines (MGRILs) of $F_{11}$ were derived from the cross between Milyang 23, Tongil type, and Gihobyeo, japonica type. They were evaluated for 7 traits of chemical property in rice. Transgressive segregation was observed for all traits examined. Eight significant QTLs were detected (LOD$\geq$2.0) for five traits, including two QTLs for amylose content, two QTLs for potassium content, one QTL for ratio of magnesium to potassium, one QTL for fat content and two QTLs for ash content. Phenotypic variation explained by each QTL ranged from 7.2% to 14.4%. However, no significant QTL was detected for magnesium and protein contents. In amylose content and ash content M alleles originated from Milyang 23 were responsible for increasing these traits and J alleles originated from Gihobyeo also responsible for increasing these traits. Pleiotropic effects of single QTLs on different traits are observed.

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.554-556
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• 1993

A chemical investigation of the stem bark of Melia azedarach var. Japonica (Meliaceae) has led to a new limonoid, 12-hydroxyamoorastatone (1), whose structure has been elucidated by spectroscopic measurements including 2D-NMR. The 2D-NOESY experiment on its di-p-bromobenzoate derivative (1a) has established the relative configuration of 1.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.1
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• pp.41-48
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• 1986

This experiment was carries out to study on the effect of temperature raising rate to chemical composition of tobacco leaves during the midrib drying stage of flue-curing. The results were as follows : In the case of the temperature raising rate became more rapidly during midrib drying stage. It had a tendency to increase in oxailic acid, succinlc acid, ammonia, polyphenol; there was a large loss of total sugar, reducing sugar, malic acid, palmitic acid and linolenic acid; leaf color became more reddish; the leaf quality index value decreased, thereby the quality of external appearance deteriorated. It is desirable that the temperature raising rate had to be more slowly.

• Proceedings of the Korean Society of Tobacco Science Conference
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• 1999.05a
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• pp.22-22
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• 1999

• Proceedings of the Korean Society of Tobacco Science Conference
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• 2000.05a
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• pp.27-27
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• 2000