• Title/Summary/Keyword: timber species

Search Result 241, Processing Time 0.022 seconds

Isolation and Characterization of Thermostable Xylanase-producing Paenibacillus sp. DG-22. (내열성 Xylanase를 생산하는 Paenibacillus sp. DG-22 균주의 분리 및 효소 특성)

    • Microbiology and Biotechnology Letters
    • /
    • v.32 no.1
    • /
    • pp.22-28
    • /
    • 2004
  • A new moderate thermophilic bacterial strain DG-22 which produces thermostable xylanase was isolated from a timber yard soil in Kyungju, Korea. On the basis of morphological, biochemical and phylogenetic studies the new isolate was identified as a Paenibacillus species. Production of xylanase in this strain was strongly induced by adding xylan to the growth medium and repressed by glucose or xylose. No cellulase activity was detected. The temperature and pH for optimum activity were 8$0^{\circ}C$ and 5.0-5.5, respectively. The crude xylanase was stable at $60^{\circ}C$ and retained 60% of initial activity after 2h at $70^{\circ}C$. Zymogram analysis of the culture supernatant showed two xylanase active bands with molecular masses of 22 and 30 kDa.

A Study on Heat Transfer of Plywood for Wood Based Flooring by Veneer Composition (마루판용 합판의 단판 구성요소에 따른 열전달 특성에 관한 연구)

  • Pi, Duck-Won;Choi, Song-Kyu;Kang, Ho-Yang;Kang, Seog-Goo
    • Journal of the Korea Furniture Society
    • /
    • v.23 no.3
    • /
    • pp.298-304
    • /
    • 2012
  • Since 1990's, a flooring based on plywood has gotten customers' demand. Costs of raw material and production increased because of changed environment of industry. Tropical timber such as Red Meranti (Shorea acuminate) used for raw material of the floor has been depleting beside countries in South Eastern Asia changed species of afforestation. As a result, it gets hard to secure good quality of raw material for plywood. Moreover plywood price is increased suddenly after earthquake in Japan. Eucalyptus (Eucalyptus globulus) in china has been using for raw material as a countermeasure of changed environment of industry. In this study, possibility of using flooring consisted of Eucalyptus veneer as a core layer was checked by heat transfer experiments. Flooring consisted of Red Meranti was used for comparison. Two factors which impact on heat transfer are a type of density gradient and density difference between Long-grain veneer and Short-grain veneer. Red Meranti samples are 'M' type of density gradient on the other hand Eucalyptus samples are 'W' type of density gradient.

  • PDF

Development of Oriented Strand Board from Acacia Wood (Acacia mangium Willd): Effect of Pretreatment of Strand and Adhesive Content on the Physical and Mechanical Properties of OSB

  • Febrianto, Fauzi;Royama, Lincah Ida;Hidayat, Wahyu;Bakar, Edi S.;Kwon, Jin-Heon;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
    • /
    • v.37 no.2
    • /
    • pp.121-127
    • /
    • 2009
  • Acacia wood (Acacia mangium Willd.) is the most popular fast growing tree species planted in timber estate in Indonesia and is considered to be very valuable raw materials for structural composite products. The objective of the research was to evaluate the properties of OSB prepared from A. Mangium wood with or without immersing the strands to hot water at $80^{\circ}C$ for 2 hours. MDI adhesive was used in 3 levels i.e., 3%, 5%, and 7%. The moisture content of strand was 7%. The results indicated that immersing strands in hot water for 2 hours at $80^{\circ}C$ prior to manufacture OSB improved significantly the mechanical peoperties (i.e., MOR and MOE) of OSB. The higher the adhesive content resulted in the better the dimensional stabilisation (i.e., water absorption and thickness swelling) and the mechanical properties (i.e., MOR, MOE and IB) of OSB. OSB prepared from hot-water immersed strands with 5% adhesive content has met all parameters requirement on the JIS A 5908 (2003) standard.

An Application of Linear Programming to Multiple-Use Forest Management Planning (다목적(多目的) 산림경영계획(山林經營計劃)을 위한 선형계획법(線型計劃法)의 응용(應用))

  • Park, Eun Sik;Chung, Joo Sang
    • Journal of Korean Society of Forest Science
    • /
    • v.88 no.2
    • /
    • pp.273-281
    • /
    • 1999
  • In this study, linear programming (LP) was applied to solving for optimal harvesting schedules of multiple-use forest management in Mt. Kari area managed by Chunchun National Forest Station. Associated with the geographic characteristics, the study area was classified into 4 large management units or watersheds and simultaneously applied were the site-specific levels of management constraints : nondeclining yield, initial cut for existing stands, % cut area, the volume of soil erosion, timber production and carbon storage, ending inventory condition and % area species selection for regeneration. The problem was formulated using both Model I and Model II techniques. In this paper, the formulations are presented and the results of the optimal solutions are discussed for comparison purposes.

  • PDF

A Survey on the Woody Plants Introduced to the Southern Part of Korea (우리나라 남부지방(南部地方)에 분포(分布)하는 외래수목조사(外來樹木調査))

  • Kim, Sam-Sik
    • Journal of Korean Society of Forest Science
    • /
    • v.26 no.1
    • /
    • pp.31-41
    • /
    • 1975
  • This work was carried out from March 1963 to December 1974 to investigate exotic woody plants in the southern part of Korea. The author enumerated 263 kinds of woody plants; 203 species, 40 varieties, and 17 forms which belong to 136 genera and 63 families. Among 263 sorts of woody plants 99 were introduced from Japan, 87 from China, 32 from the North America, 17 from Europe, 13 from Australia, 8 from India and 8 from central part of Asia, etc. On the use of those trees of today 151 have been used for an ornamental source, 49 for timber, 22 for edible, 16 for medicinal and 22 for the others.

  • PDF

Termite Resistance of Impregnated Jabon Wood (Anthocephalus Cadamba Miq.) with Combined Impregnant Agents

  • Arsyad, Wa Ode Muliastuty;Basri, Efrida;Hendra, Djeni;Trisatya, Deazy Rachmi
    • Journal of the Korean Wood Science and Technology
    • /
    • v.47 no.4
    • /
    • pp.451-458
    • /
    • 2019
  • Jabon (Anthocephalus cadamba Miq.) is a fast-growing species that exhibits a lower natural resistance than that exhibited by the timber sourced from natural forests. Jabon's resistance to termite attack can be improved by impregnating its wood structure with poisonous organic materials. This study examined jabon's resistance to termite attack when impregnated with wood vinegar and an animal adhesive. The wood specimens were impregnated using sengon wood vinegar and an animal adhesive (8% and 10%, respectively) using a vacuum pressure machine. The specimens were tested for their resistance to subterranean and dry-wood termites according to Indonesian National Standard (SNI 7207-2014). The results denoted that jabon impregnated with wood vinegar and an animal adhesive concentration of at least 8% with the addition of 4% borate was effective to resist termite attacks. The impregnated jabon exhibited a lower weight loss and higher termite mortality when compared with those exhibited by the control specimens. Thus, the resistance class improved from class IV to class I.

Text Mining of Wood Science Research Published in Korean and Japanese Journals

  • Eun-Suk JANG
    • Journal of the Korean Wood Science and Technology
    • /
    • v.51 no.6
    • /
    • pp.458-469
    • /
    • 2023
  • Text mining techniques provide valuable insights into research information across various fields. In this study, text mining was used to identify research trends in wood science from 2012 to 2022, with a focus on representative journals published in Korea and Japan. Abstracts from Journal of the Korean Wood Science and Technology (JKWST, 785 articles) and Journal of Wood Science (JWS, 812 articles) obtained from the SCOPUS database were analyzed in terms of the word frequency (specifically, term frequency-inverse document frequency) and co-occurrence network analysis. Both journals showed a significant occurrence of words related to the physical and mechanical properties of wood. Furthermore, words related to wood species native to each country and their respective timber industries frequently appeared in both journals. CLT was a common keyword in engineering wood materials in Korea and Japan. In addition, the keywords "MDF," "MUF," and "GFRP" were ranked in the top 50 in Korea. Research on wood anatomy was inferred to be more active in Japan than in Korea. Co-occurrence network analysis showed that words related to the physical and structural characteristics of wood were organically related to wood materials.

Derivation of Basal Area Projection Function for Forest Plantation Using Medium (3-5years) Measurement Cycles (중간(中間) 측정(測定) 주기(週期) (3-5년)를 이용(利用)한 인공림(人工林)의 흉고단면적(胸高斷面績) 추정(推定) 함수(函數)의 유도(誘導))

  • Lee, Sang-Hyun
    • Journal of Korean Society of Forest Science
    • /
    • v.89 no.4
    • /
    • pp.463-469
    • /
    • 2000
  • Douglas-fir (Pseudotsuga menziesd Mirb. Franco) is highly regarded as a commercial timber species throughout the world in part due to its fast growth relative to many other species. In this study, basal area per hectare equation for Douglas-fir plantations in Southland of New Zealand has been developed based on medium measurement cycles of permanent sample plots data set. The function was developed using the algebraic difference equation method, and various sigmoid-shaped projection equations were used. Parameter estimation was obtained by non-linear routine of the SAS. As a result, of the functions tested a variant of the Schumacher polymorphic function including site index and thinning term as predictor variables showed the higher precision of the fitting. The results indicate that site index is positively correlated with basal area growth. And the thinning term was found to be useful to increase precision of the model.

  • PDF

Flora of Gitdae-bong (Gapyeong-gun, Gyeonggi-do) (깃대봉(경기.가평)의 식물상)

  • Lee, Sun-Kyoung;Han, Jun-Soo;Yoo, Ki-Oug
    • Korean Journal of Plant Resources
    • /
    • v.24 no.5
    • /
    • pp.564-583
    • /
    • 2011
  • The flora of Gitdae-bong area were investigated from March, 2009 to September, 2010. The vascular plants were summarized as 435 taxa; 90 families, 272 genera, 380 species, 3 subspecies, 45 varieties, and 7 forma. Among the investigated 435 taxa, twelve Korean endemic, eight rare plants and 68 specially designated plants by Ministry of Environment were also included. The naturalized plants were 15 taxa and percent of naturalized plant species was 3.4%. Usefulness of plants of 435 taxa listed consists of 203 taxa (46.7%) of edible plants, 141 taxa (32.4%) of medicinal plants, 64 taxa (14.7%) of pasture plants, 44 taxa (10.1%) of ornamental plants, 18 taxa (4.1%) of timber plants, 15 taxa (3.4%) of fiber plants and 4 taxa (0.9%) of industrial plants.

Floristic Study of Mt. Baegam (Hongcheon-gun, Gangwon-do) (백암산(강원, 홍천)일대의 관속식물상)

  • Cheon, Kyeong-Sik;Kim, Kyung-Ah;Yoo, Ki-Oug
    • Korean Journal of Plant Resources
    • /
    • v.29 no.2
    • /
    • pp.171-188
    • /
    • 2016
  • This study was carried out to investigate the flora of Mt. Baegam (1,099 m) from March, 2014 to July, 2015. The vascular plants were summarized as 506 taxa, including 90 families, 293 genera, 435 species, 5 subspecies, 58 varieties and 8 forms. Among the investigated 506 taxa, 14 Korean endemic, 16 rare plants and 80 specially designated plants (V degree: 3 taxa, IV degree: 7 taxa, III degree: 22 taxa, II degree: 21 taxa, I degree: 27 taxa) by the Ministry of Environment were also included. The naturalized plants were 36 taxa including 3 ecosystem disturbance wild plant. The urbanization index and percent of naturalized plants species were estimated as 11.2% and 7.1%, respectively. Useful plants of 506 taxa listed consists of 207 taxa (40.9%) of edible plants, 200 taxa (39.5%) of pasture plants, 146 taxa (28.9%) of medicinal plants, 58 taxa (11.5%) of ornamental plants and 15 taxa (3.0%) of timber plants, respectively.