• Journal of the Korean Wood Science and Technology
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• 제20권3호
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• pp.67-78
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• 1992

The application of white-rot fungi to pulping and bleaching processes has been studied at the Wood Chemistry Laboratory in Kyushu University, cooperatively with the Biotechnology Laboratory of Kobe Steel, Ltd. Some successful results of the studies for a biomechanical pulping process, biobleaching of hardwood and softwood kraft pulp, as well as chlorine free biobleaching of oxygen-prebleached hardwood kraft pulp are dealt with. Biological treatment of the pulp bleaching effluent is also described.

• Journal of the Korean Wood Science and Technology
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• 제32권3호
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• pp.25-32
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• 2004

This research work explored physical and mechanical properties of impregnated sawdust boards from three softwood species (P, densifora, L. kaemferi, and P. koraiensis) with phenol-formaldehyde (PF) resin by various vacuum treatment methods of combining pressure, vacuum, and ultrasonic waves. Simultaneous vacuum and ultrasonic wave treatments with no pressure resulted in the greatest increase in resin content, density, dimensional changes (thickness and length), bending strength, and hardness of impregnated board. This result seemed to be attributed to the ultrasonic wave treatment.

• 한국임상수의학회지
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• 제16권2호
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• pp.253-256
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• 1999

The influence of essential oils from aboriginal softwoods as Pinus densiflora, Pinus koraiensis, Chamaecyparis obtusa and Chamaecyparis pisifera on the motor coordination, pulse, mean blood artery pressure and pain reducing test was investigated in mice and rats. The motor coordination of mouse was not induced by the inhalation of each oil. Furthermore, these oils did not alter the changes of the mean blood pressure and pulse rate. Chamaecyparis pisifera trand to reduce the mean blood pressure. The abdominal pain induced by acetic acid was reduced only by an essential oil from Pinus koraiensis in mouse.

• Mycobiology
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• 제28권1호
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• pp.47-50
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• 2000

The capability of higher ascomyceteous fungi to cause typical soft-rot decay for wood under laboratory conditions is reviewed and discussed. Fungi tested were extremely active in the decomposition of timbers. Scanning electron micrographs illustrated typical soft-rot decay pattern of higher wood decay ascomycetes, with the exception of H. trugodes that caused white-rot decay. Most of the fungi tested could be grouped as soft-rot fungi that showed typical soft-rot type II. Hypha confined primarily to the resin canals in softwoods or vessel elements in hardwoods and spread tracheid to tracheid via pits of cell wall to cell wall with mechanical force.

• Journal of the Korean Wood Science and Technology
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• 제47권4호
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• pp.509-518
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• 2019

This study analyzed the effect of organic solvent extractives on the classification of wood species via near-infrared spectroscopy (NIR). In our previous research, five species of Korean softwood were classified into three groups (i.e., Cryptomeria japonica (cedar)/Chamaecyparis obtuse (cypress), Pinus densiflora (red pine)/Pinus koraiensis (Korean pine), and Larix kaempferi (Larch)) using an NIR-based principal component analysis method. Similar tendencies of extractive distribution were observed among the three groups in that study. Therefore, in this study, we qualitatively analyzed extractives extracted by an organic solvent and analyzed the NIR spectra in terms of the extractives' chemical structure and band assignment to determine their effect in more detail. Cedar/cypress showed a similar NIR spectra patterns by removing the extractives at 1695, 1724, and 2291 nm. D-pinitol, which was detected in cedar, contributed to that wavelength. Red pine/Korean pine showed spectra changes at 1616, 1695, 1681, 1705, 1724, 1731, 1765, 1780, and 2300 nm. Diterpenoids and fatty acid, which have a carboxylic group and an aliphatic double bond, contributed to that wavelength. Larch showed a catechin peak in gas chromatography and mass spectroscopy analysis, but it exhibited very small NIR spectra changes. The aromatic bond in larch seemed to have low sensitivity because of the 1st overtone of the O-H bond of the sawdust cellulose. The three groups sorted via NIR spectroscopy in the previous research showed quite different compositions of extractives, in accordance with the NIR band assignment. Thus, organic solvent extractives are expected to affect the classification of wood species using NIR spectroscopy.

• Journal of the Korean Wood Science and Technology
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• 제45권4호
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• pp.409-418
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• 2017

This work attempted to manufacture glued-laminated timber (Glulam) bonded with melamine-urea-formaldehyde (MUF) resin adhesives at various melamine contents from 20% to 50% under high frequency (HF) heating for a very short time. Two preparation methods were employed to prepare MUF resin adhesives with different melamine contents: one-batch method of synthesizing MUF resins in a single batch, and two-batch method of mixing urea-formaldehyde (UF) resin with melamine-formaldehyde (MF) resin that had been synthesized separately. As the melamine content increased, the gelation time and peak temperature of MUF resins decreased. The adhesion performance of plywood showed that the one-batch MUF resin adhesive with 50% melamine content only satisfied the standard requirement of water resistance. Thus, the one-batch MUF resin adhesive with 50% melamine content was applied for bonding wood lamina from four softwood species such as Japanese larch, Korean red pine, Korean pine and Japanese cedar to manufacture Glulam under HF heating. All Glulam samples bonded with the one-batch MUF resin adhesives with 50% melamine content except those from Korean Red Pine satisfied the requirement in water soaking or boiling water delamination test as an exterior grade Glulam. The presence of rosin in Korean Red Pine was believed to be responsible for its poor adhesion. These results showed that the one-batch MUF resin adhesives with 50% melamine content provided acceptable water resistance with exterior grade Glulam manufactured under HF heating.

• 한국산림과학회지
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• 제107권2호
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• pp.126-139
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• 2018

생식구조를 중심으로 나자식물의 바르지 않은 한국어 용어를 바로 잡고 국제용어에 상응하는 나자식물의 한국어 용어를 제안하여 정리하였다. 즉, 나자식물 용어에 '꽃(花)'이나 '열매(果實)'의 의미가 들어 있는 용어를 중심으로 바로 잡았다. 예를 들어, '열매' 또는 '구과(毬果)'라고 부르는 'cone'은 '종구(種毬)'로 수정하고, '종린(鍾鱗)' 또는 '실편(實片)'이라고 부르는 'cone scale', 'ovuliferous scale'은 '종린(種鱗)' 하나로 정리하고, '화분낭(花粉囊)'으로 부르는 'microsporangium', 'pollen sac'은 '소포자낭(小胞子囊)'으로 부르고, 화분(花粉)이라고 부르는 'pollen'은 '소포자(小胞子)' 또는 '웅성배우자체(雄性配偶者體)'로 수정할 것을 제안했다. '암꽃', '자화수(雌花穗)', '구화수(毬花穗)', '구상화서(毬狀花序)', '자화서(雌花序)' 또는 '자성구화수(雌性毬花穗)' 등으로 부르는 'female cone', 'ovulate cone'은 '암종구(種毬)', '자종구(雌種毬)', '자성종구(雌性種毬)'로 정리했으며, 나자식물에는 '꽃(花)'이 없음에도 불구하고 '화수(花穗)', '화서(花序)' 등으로 부르는 'strobilus'는 '포자수(胞子穗)' 또는 '포자낭수(胞子囊穗)'로 정리했다. 생식구조와 관련이 없는 용어로 '구과식물(毬果植物)' 또는 심지어 '침엽수(針葉樹)'라고 부르는 'conifers(coniferous plants)'는 '종구식물(種毬植物)' 또는 '송백류(松栢類)'로 정리했다.

• Journal of the Korean Wood Science and Technology
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• 제28권4호
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• pp.61-71
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• 2000

The effect of the treatment with CCFZ, FR-4, and PEG400 from butt end on the dimensional stability and bending properties was examined. Three softwood species such as red pine, Korean white pine and Japanese larch and three hardwood species such as poplar, alder and oak were investigated in this research. Shrinkage of red pine, Korean white pine, poplar, and alder treated with PEG400 decreased. However, there was no significant decrease of shrinkage in Japanese larch and oak. The decrease of shrinkage when moisture content changed from about 20% to 10% was larger than that at any other phase. In regard to the effect of treatment on bending properties, bending MOE and MOR of all specimens treated with PEG400 decreased significantly. Especially in the case of red pine, poplar, and alder treated with PEG400, bending MOR reduced 9%, 14%, and 12%, respectively. Reductions of MOR of the hardwood was also much larger than that of the softwood. However, in all species, treatment with CCFZ and FR-4 did not affect the change of bending MOE and MOR significantly. Comparing the large specimen which also included heartwood with the small specimen which included only treated sapwood, there was a difference in the change of bending MOE and MOR between them. The large specimens of Korean white pine, alder and Poplar, which had a relatively low proportion of sapwood(18~22%), showed the decrease of MOR by 11~13% more than that of small specimens, while red pine, Japanese larch and oak, which had a relatively high proportion of sapwood(35~40%), showed little decrease. It means that bending MOE and MOR of structural wood treated from butt end should be considered in terms of sapwood proportion as well as effect of treated chemicals.

• Journal of the Korean Wood Science and Technology
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• 제45권4호
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• pp.399-408
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• 2017

Research on the rapid and accurate prediction of physical properties of wood using near-infrared (NIR) spectroscopy has attracted recent attention. In this study, partial least squares analysis was performed between NIR spectra and air-dried specific gravity of five domestic conifer species including larch (Larix kaempferi), Korean pine (Pinus koraiensis), red pine (Pinus densiflora), cedar (Cryptomeria japonica), and cypress (Chamaecyparis obtusa). Fifty different lumbers per species were purchased from the five National Forestry Cooperative Federations of Korea. The air-dried specific gravity of 100 knot- and defect-free specimens of each species was determined by NIR spectroscopy in the range of 680-2500 nm. Spectral data preprocessing including standard normal variate, detrend and forward first derivative (gap size = 8, smoothing = 8) were applied to all the NIR spectra of the specimens. Partial least squares analysis including cross-validation (five groups) was performed with the air-dried specific gravity and NIR spectra. When the performance of the regression model was expressed as $R^2$ (coefficient of determination) and root mean square error of calibration (RMSEC), $R^2$ and RMSEC were 0.63 and 0.027 for larch, 0.68 and 0.033 for Korean pine, 0.62 and 0.033 for red pine, 0.76 and 0.022 for cedar, and 0.79 and 0.027 for cypress, respectively. For the calibration model, which contained all species in this study, the $R^2$ was 0.75 and the RMSEC was 0.37.

• 한국식품영양과학회지
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• 제30권6호
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• pp.1204-1209
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• 2001

본 연구는 한국에 널리 분포되어 있는 대표적인 침엽수중에 혈액지질에 영향을 미치는 성분이 있는지를 검색하는 것을 목적으로 시도되었다. 1차적으로 미국측백과 뚝향나무의 유기 용매와 수용성 추출물을 흰쥐에게 경구 투여하여 체중 증가, 장기 무게, 혈액지질성분 및 혈당의 변화를 관찰하였다. 추출물의 섭취는 체중증가와 간, 신장, 비장과 같은 장기무게에 유의적인 차이가 없어 일반적인 성장에는 영향을 주지 않는 것으로 보인다. 그러나 체내 저장지방은 뚝향나무의 유기용매층 섭취군에서 유의적으로 낮았다. 그리고 혈청내 총 지방량은 고지방 대조군이 저지방 대조군에 비해 유의적으로 높았으며, 뚝향나무의 유기용매층이 유의적으로 낮아 뚝 향나무의 유기용매층이 혈액 지질저하 효과가 있는 것으로 선정되었다. 2차적으로 뚝향나무의 유기용매층을 3분획하여 횐쥐를 대상으로 혈액지질성분과 혈당, 빈혈지표등을 관찰하였다. 결과를 보면 JCDM2가 체내 지방축적량을 유의적으로 낮추었으며, 혈청내 총 콜레스테롤과 중성지방량이 유의적이지는 않으나 낮은 경향을 보였다. 그리고 JCDM2의 50%이상을 차지하고 있는 물질로 communic acid가 순수 분리되었다. 본 연구는 아직 시도되지 않았던 수목의 혈액내 지질 저하효과를 관찰하는 기초연구로 실험 결과, 뚝향나무의 유기용매층에서 효과가 있었으며 그 주요 물질은 communic acid로 관찰되었다.