• 펄프종이기술
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• 제36권5호
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• pp.62-68
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• 2004

The amount of non-lignin components in unbleached and oxygen-delignified kraft pulps and their impact on lignin determinations was investigated. The lignin analyses investigated were kappa number and Klason lignin in conjunction with acid-soluble lignin. The species investigated were loblolly pine, and aspen. The non-lignin components that impacted on lignin determination were residual extractives and hexenuronic acid in unbleached and oxygen-delignified kraft pulps. In the hardwoods, significant amounts of extractives remained after kraft pulping and oxygen delignification. These residual extractives in the hardwood pulps had an impact on the lignin determination, more so on the acid lignin method than kappa number. Hexenuronic acid only impacts on kappa number determination both softwood and hardwood pulps, not on acid lignin. Hexeneuronic acid contributed as lignin content more in aspen than pine pulps, and more in oxygen-delignified than unbleached kraft pulps. Impact of hexenuronic acid on should be corrected both softwood and hardwood pulps for accurate kappa number.

• 한국가구학회지
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• 제26권2호
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• pp.179-185
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• 2015

A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood G. biloba, ring-porous wood A. altissima, and diffuse- porouswood D. kaki. In radial direction, ray cells and in longitudinal direction tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents (MC). The length, lumen diameter, pit diameter, end wall pit diameter and the numbers of end wall pits determined for the flow rate. The liquid flow in the those cells was captured via video and the capillary flow rate in the ones were measured. Vessel in hardwood species and tracheids in softwood was found to facilitate prime role in longitudinal penetration. Radial flow speed was found highest in ray parenchyma of G. biloba. Anatomical features like the length and diameter, end-wall pit numbers of ray parenchyma were found also responsible fluid flow differences. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Therefore, the average liquid penetration depth in longitudinal tracheids of G. biloba was found the highest among all cells considered in D. kaki and A. altissima.

• Journal of Plant Biotechnology
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• 제3권2호
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• pp.45-57
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• 2001

Trees have the ability to undergo secondary growth and produce a woody body. This tree-specific growth is affected by the secondary vascular system and the developmental continuum of secondary phloem and xylem. Secondary growth is one of the most important biological processes on earth. Considering its economic and environmental significance, our knowledge of tree growth and development is surprisingly limited. Trees have received little attention as model species in plant science, as most Plant biology questions can be best addressed by using herbaceous model species, such as Arabidopsis. Furthermore, tree biology is difficult to study mainly due to the inherent problems of tree species, including large size, long generation time, large genome size, and recalcitrance to biotechnological manipulations. Despite all of this, one must rely on trees as models to study tree-specific questions, such as secondary growth, which cannot be studied effectively in non-woody model species. Recent advances in genomics technology provide a unique opportunity to overcome these inherent tree-related problems. Several groups, including our own, have been successful in studying the biology of wood formation with a variety of hardwood and softwood species. In this article, 1 first review the current understanding of tree growth and then discuss the recent attempts to fully explore and realize the potential of molecular biology as a tool for enhanced understanding of secondary growth.

• 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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• 제81권2호
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• pp.124-138
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• 1992

본 논문은 한국(韓國)의 장기목재수요함수(長期木材需要函數)를 추정(推定)하기 위한 목적으로 수행되었다. 1970년부터 1990년까지 21년간의 시계열자료(時系列資料)가 분석자료로서 이용되었으며, 수요전망은 2030년까지의 예측치를 제시하였다. 특히 본 연구는 침엽수와 활엽수를 구분하여 용도별로 수요함수를 추정하였으며, 더미변수(變數)의 확정방법(確定方法)에 관하여도 자세한 검토가 이루어졌다는 데 그 특징이 있다. 분석결과(分析結果)를 살펴보면 현재 활엽수에 대한 침엽수의 대체효과가 빠른 속도로 진행되고 있는데. 이러한 경향은 앞으로도 지속될 것인 바, 주로 건축 토목 등에 소요되는 일반 용재를 중심으로 나타날 것으로 예상된다. 수종을 불문하고 대부분의 용도가 증가할 것으로 예상되는 반면, 갱목용재의 경우는 오히려 감소할 것으로 예상된다. 수종별 용도별 목재수요함수(木材需要函數)에 대한 파라메타 추정결과(推定結果)를 보면 GDP에 대한 수요탄력성이 다른 설명변수의 탄력성보다도 상대적으로 높은 것으로 나타나고 있으며, 인구 및 대체재의 영향은 뚜렷하지 않은 것으로 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제16권4호
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• pp.40-47
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• 1988

Our plywood manufacturing industries which entertained prosperous stage in late 1970's have come to be in face of the problems of conceedingly obtaining good quality logs and yield up-grading, which is considered by future-replaceable forest resources. In view of this point, manufacturing characteristic on softwood plywood using Japanese larch, pitch pine as domestic plantation species, and western hemlock as foreign species was studied. In this study, veneer- and plywood manufacturing yields were discussed in relation to log properties and veneer defects (knots). The summarized conclusions were as follows: 1. The majority of sample logs belonged to second grade on the standard. And, eccentricity of larch was the highest 11%, about 2 times those of pitch pine, hemlock. 2. Knot frequency of occurrence of larch reached 19% within log height 8m, and pitch pine 13% within 4m. Correspondingly, the log height of larch available for plywood manufacture was higher by about 2 times that of pitch pine. 3. In the knot types, most of knots of larch appeared dead, whereas those of pitch pine and hemlock appeared live. In size of knots, larch and hemlock showed relatively small 1-2cm dia. by 70% or more and pitch pine did the larger 24cm by 65%. Generally the more knot emerged in the inner side of veneer than the outer. 4. Plywood manufacturing yields by peeling with spindle revolution lathe were 37% in larch > 32% in hemlock> 26% in pitch pine. S. Jointed core veneer yields by peeling with outer perimeter back-up lathe were 55% in hemlock> 53% in larch> and 48% in pitch pine.

• 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.

• 한국자원식물학회지
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• 제15권3호
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• pp.269-278
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• 2002

본 연구는 병꽃나무의 화훼작목화를 목적으로 적정 삽목번식 방법을 개발하기 위하여 실시하였다. 병꽃나무의 삽목에 적합한 삽목용토를 개발하기 위하여, 모래, 펄 라이트, 질석 단용과 질석 : 펄라이트(1:1) 혼용처리한 용토에 삽목한 결과 숙지삽, 녹지삽, 반숙지삽 공히 펄라이트 처리구에서 가장 높은 발근율을 보였다. 특히 녹지삽은 모든 처리구에서 70.0~76.7%의 발근율을 보여, 숙지삽에 비해 약2.8배 정도 높은 발근율을 보였다. 병꽃나무의 삽목발근에 미치는 생장조절제의 영향을 조사한 결과 숙지삽의 경우에는 생장조절제의 종류에 관계없이 농도가 높을수록 대조구에 비해 발근이 촉진되는 경향이었다. 특히 NAA 500mg. L$^{-1}$처리구에서 80.0%로 가장 높은 발근율을 나타냈다. 녹지삽의 경우에는 대조구를 제외한 모든 처리구에서 80%이상의 발근율을 보였으며, 특히 NAA 100, 500mg.L$^{-1}$와 IAA 1000mg.L$^{-1}$처리구에서 96.7%의 가장 높은 발근율을 보였다. 반숙지삽의 발근율 또한 생장조절제의 종류에 관계없이 농도가높을수록 발근율이 높아지는 경향을 보였던 반면 고농도인 1000mg.L$^{-1}$처리구에서는 억제되는 것으로 나타났다. NAA 농도 및 침지시간에 따른 발근율은 숙지삽의 경우 농도가 높을수록, 침지시간이 길수록 양호한 경향이었다 녹지삽은 침지 시간이 길수록 현저하게 향상되었으며, 특히 500mg.L$^{-1}$, 30분 침지처리구에서 100%의 발근을 보였다. 반숙지삽의 경우는 처리농도가 높을수록 또한 침지시간이 길수록 발근율이 양호하였으나, 녹지 및 숙지를 삽수로 했던 것에 비해 그 정도는 낮았다.

• Journal of the Korean Wood Science and Technology
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• 제15권1호
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• pp.22-55
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• 1987

본(本) 연구(硏究)는 육안적(肉眼的) 특성(特性)에 의한 목재식별(木材識別)의 속보(續報)로써 앞으로 생산가능(生産可能)한 한국산(韓國産) 단판수종(單板樹種)의 현미경적(顯微鏡的) 목재특성(木材特性)을 조사(調査)하여 합판공업(合板工業)에 필요(必要)한 기초자료(基礎資料)를 제공하기 위하여 실시(實施)하였다. 선정(選定)된 50수종(樹種)의 현미경적(顯微鏡的) 특성(特性)을 조사(調査)하여 수종별(樹種別)로 기재(記載)하였고 이를 바탕으로 하여 침엽수재(針葉樹材) 및 활엽수재별(闊葉樹材別)로 목재식별(木材識別) 검색표(檢索表)를 간략(簡略)하게 보고(報告)하면 다음과 같다.

• 건축역사연구
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• 제16권1호
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• pp.9-28
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• 2007

We investigated the changes in the species of the woods used for Korean ancient and historic architectures, which include prehistoric excavated relics and existing wooden buildings in South Korea. The species data were collected from various sources such as excavation and repair reports, journal papers, and a few unpublished documents. We divided the building Periods as Paleolithic, Neolitic, Bronze Ages, Iron Age/Three Kingdoms, Koryo, Joseon (early, middle, late) and modem periods. In prehistoric periods, hardwoods were major species. Oak (Quercus spp.) woods dominated (94 percent in average); the others (5%) were Juglans mandshurica, Platycarya strobilacea, Castanea crenata, and few softwoods(1%). During Iron Age and Three Kingdom periods, oaks remained as a major species (57%) and others Platycarya strobilacea(21%), Castanea crenata(13%), and Pinus spp. (6%). The oak woods decreased in Koryo period and they occupied only 1.1%. Instead of oaks, pine (Pinus spp., 71%) and Zelkova serrata (22%) dominated in Koryo. In early and middle Joseon periods, pine woods (73%) remain as a major species and the others were oaks (14%) and Zelkova serrata (9%). As late Joseon came, the pine woods occupied more than 88%. In the late 19th and early 20th centuries, a few boreal species such as larch (Larix spp.) and spruce (Picea spp.), which grow in cold area, were found. We believe they were transported from northern Korea. The existing buildings in Korea are mainly from Joseon period and a few from late Koryo periods. During these periods, pine woods were used for most buildings. For such reason, pine woods were known as 'representative materials for historic buildings'. but earlier times, broad-leaved trees, i.e., oak and Zelkova woods were major materials. The changes in building materials resulted from both climate and human impacts. The dry climate and disturbed forests induce more pines in the mountains. We also compared the wood qualities of the species and found that Zelkova woods were superior ones and deserved more planting for future demands in the repair for historic buildings.