• Journal of the Korean Wood Science and Technology
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• 제26권4호
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• pp.34-42
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• 1998

Three hardwood (ash, alder and black locust) and three softwood (Japanese red pine, radiata pine and Western hemlock) specimens were dried in microwave(MlW) oven and their drying rates were obtained. Their specific permeabilities were also measured by using a modified liquid permeability measuring device. The correlation between the M/W drying rates and permeabilities of six species were statistically analyzed. It was revealed that within a species there is a logarithmic relationship between the M/W drying rates and average moisture contents and that among species there is a linear relationship between the M/W maximum drying rates and the average specific permeabilities. A exception was Western hemlock, which was of low permeability and of high drying rate. A Me-time equation, which showed a good agreement with the actual data, was derived. Thus using this equation the moisture contents of wood and the drying end points of M/W drying could be predicted. Infrared images of the thermal distribution in wood were illustrated.

• Journal of the Korean Wood Science and Technology
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• 제21권1호
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• pp.15-20
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• 1993

X-ray diffractograms of the vessel elements and the wood fibers of Quercus variabilis BLUME were recorded and resolved into characteristic reflections of cellulose I. Some differences were observed in the ratio of integrated intensity and crystallinity index between vessel elements and wood fibers. Present results suggest that cellulose crystal structure in the hardwood species was varied with the elements of wood.

• 보존과학회지
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• 제5권2호
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• pp.51-56
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• 1996

This paper deals with the restoration of ancient wooden bridge foundation which excavated in Seta river Shiga Prefecture, Japan. Shiga Archeological Research started a marine archeological investigation of the bridge foundation in 1987. The bridge foundation stricture excavated and have since then recovered about a lots of woods and another materials. The bridge foundation structure constructed log, timbers and stones. The species of those waterlogged wood were identified as two types, hardwood and softwood. Hardwood(log : Cyclobalanopsis) was used for below foundation and softwood (timber' Chamaecyparis obtusa Endl. Cupreessaceae) was used for base structure. One of those timber sample dated by dendrochronology, we asked Dr. Misutani*. The softwood gave a felling date of 567 A.D. In result, the ancient Seta bridge foundation structure had constructed between Asuka and Nara period. We healed the news that ancient bridge foundation excavated at Woljyongyo site in Kyongju, Korea 1987. The bridge foundation Setakarahashi is similar in plane and structure to Woljyongyo structures. The Woljyongyo site report had be of value for reference. We had planning to restore those woods. Hardwood log was got serious damage. The water content varies from 400 to $600\%$. The other timbers water content varies about $200\%$. In the Shiga Center for Archaeological Operations and the Azuchi Castle Archaeological Museum, we set up the PEG impregnation tank. Those wooden objects treated by PEG method. PEG with a molecular weight of 4000. The treatment results may be considered satisfactory. The ancient wooden Seta bridge was reconstructed in Biwako Museum which established in Oct. 1996. We must take care of indoor exhibition environments. (*Nara National Cultual Properties Research Institute).

• 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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• 제29권4호
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• pp.67-78
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• 2001

신갈나무와 이태리포플러 칩을 25 kg/$cm^2$의 압력에서 6분간 폭쇄처리하였다. 폭쇄재는 수산화나트륨(NaOH), 차아염소산나트륨(NaClO), 아염소산나트륨($NaClO_2$)을 사용한 단독 또는 다단의 공정으로 화학처리 하였다. 폭쇄재의 다단처리는 시료중의 리그닌 제거에 상당한 효과를 나타냈다. 대조구인 폭쇄재 기질의 효소 가수분해율은 25%였지만, 다단 화학약품 처리된 폭쇄재는 약 80%에 근접하는 가수분해율을 나타냈다. 효소에 의한 분해율은 수종간에 차이가 났다. 폭쇄재의 다단 화학약품 처리는 효소 가수분해액에 있어서 글루코오스 함유 비율을 증가시켰다. Cellulase의 흡착은 기질의 리그닌 함량과 비례하여 증가하였지만, 반면에 기질의 결정화도, 공극면적 및 비표면적은 효소흡착에 큰 영향을 미치지 않았다. 본 연구에서 제시된 전처리 당화공정에 따르면, 100 kg의 활엽수재로부터 약 37~40 kg의 글루코오스 생산이 가능하리라 생각된다.

• Applied Microscopy
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• 제34권4호
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• pp.271-276
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• 2004

Biscogniauxia속에 속한 대다수의 종들은 목재를 분해균으로 알려져 있으며, 목질내지는 탄소질이며 암갈색의 자좌를 가진 Xylariales에 속하여 있다. Daldinia concentrica와 Biscogniauxia에 속한 목재부후균이 심하게 부후된 활엽수에서 분리되었으며 이는 광학현미경 및 전자현미경을 이용하여 고찰하였다. Daldinia concentrica는 국내 최초의 전자현미경을 이용한 미세구조학적 고찰이다. 또한, Biscogniauxia속 미동정 부후균은 $11.4\;15.6{\times}9.6\;12.0{\mu}m$ 크기의 자낭포자를 가지고 있으며, 국내에서 발견된 비슷한 종들과 비교 분석하였다.

• 한국가구학회지
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• 제17권3호
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• pp.37-43
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• 2006

The wood anatomy of Mangifera indica belonging to the species of Anacardiaceae native to Bangladesh was described. The species of this family was distinctive in having growth rings, thin-to thick-walled, nonseptate libriform fibres, vessels with simple perforation plate and nonvestures intervessel pittings. Paratracheal axial parenchyma was vasicentric, lozenge-aliform and confluent. Axial parenchyma band more than 3 cells wide and in marginal or in seemingly marginal bands. 3-4 cells per axial parenchyma was dominantly present. Ray height was less than 1mm. Body ray cells were procumbent with one row of upright and square marginal cells. More than one prismatic crystals of about the same size was present in upright or square ray cells.

• 한국가구학회지
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• 제17권3호
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• pp.29-36
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• 2006

Juvenile and matured wood of Populus tomentiglandulosa species of Salicaceae native grown in Korea was observed by FE-SEM and optical microscope. Species is characterized by mostly diffuse-porous, simple perforation plates, polygonal alternate non-vestured intervessel pit, medium length of vessel elements and fibres, non-septate very thin walled libriform fibres and exclusively uniseriate procumbent rays. Axial parenchyma was absent or extremely rare. Vessel and fibre length were longer in both matured and juvenile latewood than those of earlywood. Ray cell lumen diameter, ray length, number and diameter of endwall pit in ray cell, endwall pit, number and diameter of pit in lateral wall of one ray parenchyma cell, vessel ray pit number and diameter vary from juvenile early and latewood to matured wood.

• 한국산림과학회지
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• 제96권2호
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• pp.189-196
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• 2007

Allometry, basal area equations, and volume equations were developed with various tree measurement variables for the major species, Quercus mongolica and Quercus variabilis, in Korean natural hardwood forests. For allometry models, the relationships between total height-DBH, crown width-DBH, height to the widest portion of the crown-total height, and height to base of crown-total height were investigated. Multiple regression methods were used to relate annual basal area growth to tree variables of initial size (DBH, total height, crown width) and relative size (relative diameter, relative height) as well as competition measures (competition index, crown class, exposed crown area, percent exposed crown area, live crown ratio). For tree volume equations, the combined-variable and Schumacher models were fitted with DBH, total height and crown width for both species.

• 한국환경생태학회지
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• 제16권2호
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• pp.141-148
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• 2002

본 연구는 산화가 초본층의 발생 및 토양의 화학적 특성에 미친 영향을 조사하기 위해 2000년 4월 대전의 계족산에서 발생한 산화지를 대상으로 실시되었다. 식생조사는 곰솔우점림 (침엽수림)과 아까시나무우점림(활엽수림)에서 10m$\times$10m의 방형구를 설치하여 실시하였고, 초본층의 발생조사는 7월 21일 Dierssen의 우점도법을 적용하여 실시되었다. 초본층의 피도는 침\ulcorner활엽수지역 모두에서 산화지가 비산화지보다 높았으며, 출현종수는 산화지와 비산화지의 차이보다 침\ulcorner활엽수 간에 차이가 더 높았다 토양 시료는 비산화지, 그리고 산화지에서 산화 3일 후 그리고 산화 8개월 후에 0～10cm와 10～20cm 토양깊이에서 채취되었다. 토양 유기물층은 비산화지에서는 깊이가 약 1.5cm이었으나 산화지에서는 유기물층이 없었다. 산화 발생 3일 후 산화지와 비산화지 간의 토양 유기물, 전질소, 유기인산, 치환성 양이온함량, pH및 CEC는 유의적인 차이가 없는 것으로 나타났다. 또한 산화지에서 산화 3일 후와 약 8개월 후의 토양의 화학적 특성들은 일부를 제외하고는 유의적인 차이가 없었다.