• Journal of the Korean Wood Science and Technology
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• 제40권4호
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• pp.244-256
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• 2012

본 연구에서는 인도네시아의 목재자원 중 새로운 유망 목재자원을 개발하고 최근 주요 조림 수종들의 효율적 이용을 위한 기초자료를 수집하기 위해 인도네시아산 10수종의 해부학적 특성을 조사하였다. 모든 수종은 산공재로써 고립관공, 방사복합관공이 관찰되었는데, Mangium에서는 위의 특성과 더불어 접선복합관공이 관찰되었다. 접선방향의 관공 직경은 Jeunjing과 Nangka를 제외한 전 수종에서 방사방향보다 큰 값을 보였다. 특히 Nangka는 공시수종 중 가장 큰 접선방향의 관공 직경을 보였다. 단위면적($mm^2$)당 관공의 수는 Mangium, Gandaria와 Kupa가 다른 수종보다 많았으며, 특히 Kupa가 가장 많게 나타났다. 유세포의 접선방향 폭은 Gmelina, Mangium, Kupa와 Mangga가 목섬유의 접선방향 폭보다 크게 나타났으며, 그 중 Mangium이 가장 큰 폭을 보였다. 이 밖의 6수종은 반대로 목섬유의 접선방향 폭이 유세포의 접선방향 폭보다 크게 나타났으나 Durian과 Nangka는 그 차이가 타 수종에 비해 미미했다. Gmelina, Jeunjing과 Rambutan은 평복세포로 이루어진 동성방사조직이, Gandaria는 평복세포와 단열의 직립세포로 구성된 이성방사조직이, Mangium, Durian, Jengkol, Kupa, Mangga와 Nangka는 평복세포와 약 1~2열의 직립세포로 구성된 형태의 이성방사조직이 관찰되었다. Durian, Gandaria, Jengkol, Jeunjing, Mangga, Rambutan은 결정을, Jeunjing과 Mangga는 실리카를 함유하는 특징을 나타냈다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.719-725
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• 2004

Mesquite or Vilayati babul (Prosopis juliflora) is a drought resistant, evergreen, spiny tree with drooping branches and a deep laterally spreading root system. It grows in semi-arid and arid tracts of tropical and sub-tropical regions of the world and is spreading because the leaves are unpalatable and animals do not digest its seed. The mesquite has become a major nuisance; cutting or pruning its branches to form a canopy would provide shade for travelers, aid harvesting of pods, as well as make available wood for fuel. An average plant starts fruiting by 3-4 years of age and yields annually 10-50 kg pods/ tree, which can be collected from May-June and September-October. Availability of pods worldwide is estimated to be about 2-4 million metric tonnes. Ripe pods are highly palatable; on dry matter basis they contain 12% crude protein, 15% free sugar, a moderate level of digestible crude protein (7% DCP) with a high level of energy (75% TDN). The pods contain low tannin levels below those toxic to animals. Seeds contain 31-37% protein; pods should be finely ground before feeding to facilitate utilization of the seeds. Mesquite pods could replace costlier feed ingredients such as grain and bran contributing 10-50% of the diet. Phosphorus supplements need to be added when mesquite pod, exceeds 20% of animals' diet.

• Wind and Structures
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• 제37권2호
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• pp.95-104
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• 2023

The latest revision of AS/NZS 1170.2 incorporates some new research and knowledge on strong winds, climate change, and shape factors for new structures of interest such as solar panels. Unlike most other jurisdictions, Australia and New Zealand covers a vast area of land, a latitude range from 11° to 47°S climatic zones from tropical to cold temperate, and virtually every type of extreme wind event. The latter includes gales from synoptic-scale depressions, severe convectively-driven downdrafts from thunderstorms, tropical cyclones, downslope winds, and tornadoes. All except tornadoes are now covered within AS/NZS 1170.2. The paper describes the main features of the 2021 edition with emphasis on the new content, including the changes in the regional boundaries, regional wind speeds, terrain-height, topographic and direction multipliers. A new 'climate change multiplier' has been included, and the gust and turbulence profiles for over-water winds have been revised. Amongst the changes to the provisions for shape factors, values are provided for ground-mounted solar panels, and new data are provided for curved roofs. New methods have been given for dynamic response factors for poles and masts, and advice given for acceleration calculations for high-rise buildings and other dynamically wind-sensitive structures.

• 환경생물
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• 제39권2호
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• pp.218-224
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• 2021

본 연구에서는 열대우림인 브루나이 MDF와 PSF의 주요 수종(D. aromatic, D. rappa, C. arborescens)을 대상으로 초기 분해 단계의 수종별 질량 감소율과 탄질율의 변화를 파악하였다. 2019년 5월에 총 48개의 고사목 시료(15 cm ×4.8 cm ×5 cm)를 산림 지표면에 배치하고 16개월 후 수거하였다. 분해 전 수종별 고사목의 밀도(g cm^-3)는 0.64±0.01 (D. aromatic), 0.60±0.00 (D. rappa), 0.44±0.02 (C. arborescens) 등이었으며, 16개월 동안 수종별 연간 질량 감소율(%)은 6.37 (D. aromatic), 8.17 (D. rappa), 18.53 (C. arborescens) 등으로 나타났다. 부후등급은 C. arborescens에서 III등급이 약 25%로 높았으며 흰개미의 분해 흔적이 나타났다. 한편, 16개월 후 탄질율은 D. aromatic과 D. rappa에서 통계적으로 유의하게 감소하였으나, C. arborescens에서는 감소하는 경향이 유의하지 않았다. 이러한 연구 결과는 열대우림 내 고사목의 초기 분해는 밀도와 같은 수종의 물리적 특성에 따라 차이가 나타날 수 있으며, 주요 분해자의 유형에 따라 탄질율의 변화에도 상대적으로 차이가 있을 수 있음을 시사하는 것이다.

• Journal of the Korean Wood Science and Technology
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• 제34권2호
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• pp.68-77
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• 2006

The heartwood of cengal (Neobalanocarpus heimii) is known to have a high degree of decay resistance by virtue of its high extractive content. After 30 years in ground contact an utility pole of this tropical hardwood was found to be degraded only in the surface layers by cavity-forming soft rot fungi. The present work was undertaken 1) to characterize the degradation of cengal heartwood from the aspect of ultrastructure and chemistry and 2) to investigate the correlation between soft rot decay and its extractive microdistribution in wood tissues. The chemical analysis of cengal heartwood revealed the presence of a high amount of extractives as well as lignin. The wood contained a relatively high amount of condensed lignin and the guaiacyl units. Microscopic observations revealed that vessels, fibers and parenchyma cells (both ray and axial parenchyma) all contained extractives in their lumina, but in variable amounts. The lumina of fibers and most axial parenchyma were completely or almost completely filled with the extractives. TEM micrographs showed that cell walls were also impregnated with extractives and that pit membranes connecting parenchyma cells were well coated and impregnated with extractives. However, fungal hyphae were present in the extractive masses localized in cell lumina, and indications were that the extractives did not completely inhibit fungal growth. The extent of cell wall degradation varied with tissue types. The fibers appeared to be more susceptible to decay than vessels and parenchyma. Middle lamella was the only cell wall region which remained intact in all cell types which were severely degraded. The microscopic observations suggested a close correlation between extractive microdistribution and the pattern and extent of cell wall degradation. In addition to the toxicity to fungi, the physical constraint of the extractive material present in cengal heartwood cells is likely to have a profound effect on the growth and path of invasion of colonizing fungi, thus conferring protection to wood by restricting fungal entry into cell walls. The presence of relatively high amount of condensed lignin is also likely to be a factor in the resistance of cengal heartwood to soft rot decay.

• Journal of the Korean Wood Science and Technology
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• 제41권1호
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• pp.42-50
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• 2013

1980년대 중반 이후 국내 생산이 시작된 온돌마루(이하 합판마루)는 종전의 주택용 바닥재(PVC 바닥재)의 대체재로서 일반 소비자들의 폭발적인 수요를 얻어왔다. 그러나 최근 마루판 산업은 건축경기 악화 및 산업 환경의 변화로 인한 수요의 감소와 그에 따른 생산율의 저하 등의 근본적인 문제점이 있다. 최근 마루판용 합판의 원재료로 주로 사용된 동남아산 수종의 고갈 및 변화로 인한 양질의 합판원재료 확보가 어려워졌다. 이에 대한 대응책으로 중국산 유칼립투스를 원재료로 부분적으로 이용한 마루판용 합판의 대체이용이 시도되고 있다. 본 연구에서는 유칼립투스 단판을 부심판으로 제조한 복합합판의 마루판용 합판의 원재료로서의 사용 가능성을 실험을 통해 비교분석하였으며, 모든 단판이 동남아산 Meranti로 구성된 합판을 대조군으로 설정했다. 변형에 영향을 미치는 인자로 단판 간 밀도차이와 합판의 밀도경사를 이용하였다. 본 연구의 실험결과는 다음과 같다. 1) 남양재 시험편은 병판의 밀도가 다른 단판의 밀도보다 큰 M자형의 밀도경사, 유칼립투스 시험편은 반대성향의 W자형의 밀도경사를 나타내었다. 2) 종류에 따른 마루판의 변형은 마루 가공 시험편이 합판상태로 가공을 한 경우보다 최소 0.1~최대 6.25 mm 적게 나타났으며, Density Profile 측정 결과 단판 간의 밀도차가 클수록 변형이 많이 발생하였다.

• Journal of the Korean Wood Science and Technology
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• 제46권6호
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• pp.656-669
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• 2018

Tropical bamboo species, which have a very rapid growth rate, are considered as a promising non-timber forest product capable of exhibiting new functionality by carbonization technology. This study was conducted to compare the characteristics of carbonized bamboos from Andong (G. pseuudoarundinacea (Steudel) Widjaja), Hitam (G. atrovialacea), Tali (G. apus), Kuning (B. vulgaris Var. striata (Lodd. Ex Lindl)), and Ampel (B. vulgaris Scharad. ex Wendland), and Betung (D. asper). Each bamboo was carbonized at 200, 400, 600, 800, and $1,000^{\circ}C$, respectively, and their physical and anatomical characteristics were investigated. The result showed that the volume and weight of carbonized bamboo decreased with increasing carbonization temperature and showed the substantial changes of volume and weight between 200 and $400^{\circ}C$. The highest and the lowest density of carbonized samples were found in Ampel bamboo and Betung bamboo, respectively. The density of all carbonized bamboos tended to decrease after carbonization at 200 and $400^{\circ}C$ and relatively become constant afterwards. The carbonized bamboo prepared at 800 and $1,000^{\circ}C$ showed better refining degree. The results of the anatomical observation showed that the vascular diameter of carbonized bamboo decreased with increasing carbonization temperature, and the shrinkage in radial and tangential direction showed similar tendency. Statistical analysis showed that there was significant correlation between physical contraction and anatomical contraction. Based on the results of this study, comprehensive data about Indonesian bamboo charcoals could be obtained and it will be useful for future application studies.

• Journal of the Korean Wood Science and Technology
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• 제41권4호
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• pp.327-336
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• 2013

인도네시아에서 자생하는 수종인 White Jabon (Anthocephalus cadamba)과 Red Jabon (Anthocephalus macrophyllus)의 해부학적 특성을 IAWA 분류기준에 의거하여 조사 및 비교하였다. 두 수종은 산공재로서, 대부분 2~3열의 방사복합관공의 형태로 관찰되었다. 접선방향의 도관 직경은 $100{\sim}200{\mu}m$의 범위로, $mm^2$당 도관의 수는 5~20개의 범위로 분류되었고, White Jabon의 도관수가 더 많았다. 두 수종에서 $mm^2$당 고립관공의 수는 비슷했으나 복합관공은 White Jabon이 다소 많이 출현하였다. 두 수종의 횡단면에서 축방향유조직은 산재상의 형태를 보였으나, White Jabon은 그 출현빈도가 매우 낮았다. 방사단면에서 방사조직은 평복세포와 4열 이상의 직립세포로 구성된 형태가 주로 관찰되었으며, 부분적으로 직립동성형 방사조직이 관찰되었다. 접선단면상에서 White Jabon의 방사조직은 1~V3열, Red Jabon은 1~2열로 관찰되었으며, 방사조직의 높이는 White Jabon이 $420{\mu}m$, Red Jabon이 $474{\mu}m$로 나타났다. 목섬유의 평균 길이는 $900{\sim}1,600{\mu}m$의 범위였고, 수에서 수피부로 이행할수록 증가하는 방사방향 변이성을 나타냈다.

• 펄프종이기술
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• 제45권1호
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• pp.52-58
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• 2013

The effets of the pretreatments of tropical kapok fibers were evaluated in this study in terms of water sorption capacity and oil sorption capacity. The alkali treatments with NaOH resulted in the reduction of lignin, oil and hemicellulose, which were detected with FT-IR spectrum. The reduction of the lyphophilic components such as fat on kapok fiber by the ozone treatments were also measured with FT-IR spectrum. The oil sorption capacity of kapok fiber was decreased by the alkali treatments and the ozone treatments, while the water sorption capacity was increased. The liquid sorption capacity were greatly affected by the mechanical cutting of kapok fiber which exposed the big lumen of kapok fiber. The hydrophilic property of kapok fiber could be controlled by the pretreatments, which would increase the applicability of kapok fiber for preparation of various functional paper products.

• 보존과학연구
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• 통권22호
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• pp.41-52
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• 2001

The wooden building is mainly damaged by the termite which have an effect of the structure by making emptied inner part of wood. One class, Japanese termite, inhabits throughout Korea and is often detected. So the deterioration by termite attacking the wooden building needs to be controlled. Termites are over 2,800 species in the world, usually they inhabit in the tropical or subtropical region and don’t over winter in dormant condition. So their activity and distribution are chiefly restricted by temperature and humidity. The termite inhabiting in Korea is Reticulitermes speratus kyushuensis Morimoto, which known to have an optimal temperature range at $12~30^{\circ}C$ and minimum temperature at $6^{\circ}C$ for activation. These temperatures correspond to the mean temperature($5.6^{\circ}C$~$25.8^{\circ}C$) from March to November and the activity time of termitein Seoul. In addition, as a result of environmental pollution by industrial development, the climate of Korea is getting warm. The increase of mean temperature in Korea has been $1.1^{\circ}C$ for the past seventy five years, so it is expected that the damage of wooden building by termite will increase gradually. Therefore, in order to protect wooden building from damages by termite, it needs not only development of new pest control methods, but also studies on the control of environmental factors having an effect on the activity and growth of termite. For the conservation of the large cultural properties such as the wooden building in the open air, it would be effective to use the methods of fumigation, insecticidal and antiseptic chemical treatment of wood materials, soil termiticideinjection treatment, and termite colony elimination system.