• Journal of the Korean Wood Science and Technology
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• v.31 no.2
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• pp.45-51
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• 2003

One flavonoid, lignan glycosides and two diarylheptanoids were isolated from the sapwood of Betula maximowicziana. The structures were determined as : catechin 7-O-𝛽-D-xylopyranoside, lyoniresinol 9'-O-𝛽-D-glucopyranoside, 11-oxo-3, 8, 12, 17-tetrahydroxy-9-ene[7, 0]-metacyclophane and 11-oxo-3, 8, 9, 10, 12, 17-hexahydroxy[7, 0]-metacyclophane, respectively, on the basis of spectrosopic data and chemical correlations.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.61-66
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• 2004

Bleached chemithermomechanical pulp (BCTMP) was produced from CTMP of Betula maximowicziana Regel by two staged ozone-hydrogen peroxide bleaching in order to improve the optical properties of high yield pulp. This pulp was used for the evaluation of optical properties improvement, chemical characteristics of lignin in fiber and the relationship between lignin and optical properties in fiber cell wall. Hydrogen peroxide treatment improved the brightness, but the post color number (PC No.). There was little improvement on optical properties by ozone treatment, but this could be improved more by using two staged ozone-hydrogen peroxide bleaching. The hydrogen peroxide treatment did not make any change on chemical characteristics of lignin in cell wall, but by ozone treatment, it was found that the non-aromatic conjugated structure was existed in the surface of cell wall, but this could be removed by hydrogen peroxide treatment in two staged ozone-hydrogen peroxide treatment. Therefore, the optical properties was significantly improved, due to the removal of non-aromatic conjugated structure.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.375-380
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• 1999

In order to improve the optical properties of high yield pulp, bleached chemi-thermo-mechanical pulp (BCTMP) was produced from CTMP of Betula maximowicziana Regel by two staged ozone-hydrogen peroxide bleaching. This pulp was used for the evaluation of the improvement of optical properties, chemical characteristics of lignin in fiber, and the relationship between lignin and optical properties in fiber cell wall. By hydrogen peroxide treatment, the brightness was improved, but the post color number (PC No.) was not. There was little improvement on optical properties by ozone treatment, but his could be solved by using two staged ozone-hydrogen peroxide bleaching. The hydrogen peroxide treatment did not make nay change on chemical characteristics of lignin in cell wall, but by ozone treatment, it was found that the non-aromatic conjugated structure was existed in the surface of cell wall, but this could be removed by hydrogen peroxide treatment in two staged ozone-hydrogen peroxide treatment. Therefore, the optical properties was significantly improved due to the removal of non-aromatic conjugated structure.