• 제목/요약/키워드: wood turnery

검색결과 3건 처리시간 0.016초

단척 통나무와 선반가공목의 마이크로웨이브-진공 건조 (Microwave-Vacuum Drying of Short Roundwoods and Wood Turneries)

  • 강호양
    • Journal of the Korean Wood Science and Technology
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    • 제29권4호
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    • pp.25-32
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    • 2001
  • 관행열기건조방식으로는 결함없이 건조가 불가능한 목공예용 단척 통나무를 건조할 수 있는 마이크로파-진공 건조기를 개발하였다. 이 건조기는 크게 출력 1.5 kW와 주파수 2,450 MHz인 마그네트론 3개와 600리터/분 진공펌프, 100 kg 로드셀, 그리고 폭과 높이가 각각 580 mm, 길이가 1,360 mm인 cavity로 구성되어 있다. 목재건조속도는 마그네트론 주사시간과 정지시간의 비율에 따라 결정되도록 되어 있다. 건조기의 성능을 실험하기 위해 직경 12.5~25 cm, 길이 25~50 cm의 리기다소나무, 은사시나무, 그리고 자작나무 통나무를 건조하였다. 건조결과 약간의 건조결함이 있었으나 비교적 양호하였으며 매우 짧은 시간에 건조할 수 있었다. 또 오리나무와 물푸레나무 생재로 된 제기용 선반가공목은 함수율 4%까지 결함없이 건조할 수 있었다. 통나무길이에 따른 마이크로파-진공 건조의 속도도 은사시나무를 이용하여 비교하였다.

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Acacia mangium Willd. - A Fast Growing Tree for Tropical Plantation

  • Hegde, Maheshwar;Palanisamy, K.;Yi, Jae Seon
    • Journal of Forest and Environmental Science
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    • 제29권1호
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    • pp.1-14
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    • 2013
  • Acacia mangium is an evergreen fast-growing tropical tree, which can grow up to 30 m tall and 50 cm thick, under favorable conditions. It is a low-elevation species associated with rain forest margins and disturbed, well-drained acid soils. It is native to Papua, Western Irian Jaya and the Maluku islands in Indonesia, Papua New Guinea and north-eastern Queensland in Australia. Due to its rapid growth and tolerance of very poor soils, A. mangium was introduced into some Asian, African and western hemisphere countries where it is used as a plantation tree. A. mangium has good quality wood traits, such as a comparatively low proportion of parenchymatous cells and vessels, white and hard wood, and high calorific value. Therefore, it is useful for a variety of purposes, such as furniture, cabinets, turnery, floors, particleboard, plywood, veneer, fence posts, firewood, and charcoal. It is also being used in pulp and paper making because it has good pulp traits, with high yields of pulp, quality of kraft, and produces paper with good optical, physical and surface properties. Because there are significant provenance differences in growth rate, stem straightness, heartwood formation and frequency of multiple leaders, the productivity and quality also varies depending upon environmental conditions, so genetic improvement programmes have been undertaken in countries like Australia, India, Indonesia, Malaysia, the Philippines, Taiwan and Thailand. The programme includes provenance identifications and testing, plus tree selection and clonal multiplication, establishment of seed orchards and hybridization. The phenology, reproductive biology, fruit characteristics, silvicultural practices for cultivation, pest and diseases problems, production of improved planting stock, harvesting, wood properties and utilization have been discussed in this paper.

백제 사비기 목제유물의 수종 식별과 분석 (Species Identification of Ancient Wood Excavated from Capital Area in Sabi Era, Baekje)

  • 한상효;박원규
    • 보존과학연구
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    • 통권25호
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    • pp.197-226
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    • 2004
  • This study was made to identify species of archaeological wood products excavated from three sites(Kwunbuk-ni, Gungnamgi, Wanggung-ni) of Sabi Era, Baekje. These sitesare presumably considered as capital areas of Sabi Era, Baekje. Total of 220 specimens were identified into five softwoods and eighteen hardwoods. Pinus densiflora(or Pinusthunbergii) and Quercus spp. are the most common and occupied 32%, 28% of totalspecimen, respectively. The others are follows : Torreya nucifera(1%), Abiesholophylla(3%), Cryptomeria japonica(4%), Thuja spp.(2%), Chamaecyparisobutusa(2%), Salix spp.(1%), Platycarya strobilacea (3%), Alnus spp.(1%), Carpinusspp.(0.5%), Castanea crenata(9%), Zelkova serrata (6%), Celtis spp.(0.5%), Prunusspp.(2%), Rhus verniciflua(1%), Rhus trichocarpa(0.5%), Meliosma oldhamii(1%),Hovenia dulcis(1%), Kalopanax pictus(0.5%), Cornus walteri(0.5%), Styrax japonica(1%),Fraxinus rhynchophylla (0.5%), F. sieboldiana(1%).Most of the identified species have been growing in this area until nowadays. However,a few species(Cryptomeria japonica, Thuja spp. Chamaecyparis obutusa, Torreyanucifera) didn’t grow natively around this area at that time. Two species(Cryptomeriajaponica, Chamaecyparis obutusa) are endemic species of Japan, indicating international trade or exchange of woods between Baekje Kingdom and Japan in 6-7th century. Torreyanucifera grows in limited areas in Korea (south of $35^{\circ}$10′N), however, is widely distributed in the southern Japan. Quercus spp. was identified the most in implements of Baekje and Pinus densiflora(orPinus thunbergii) was in the second place. Zelkova serrata was mainly used for raw materials of turnery products, e.g., wooden container. This species produces one of the hardest woods as 0.7 in specific gravity. It indicates that iron technologies have reached some high level in Sabi Era, Beakje.

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