• Journal of the Korean Wood Science and Technology
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• 제48권4호
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• pp.458-471
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• 2020

Effect of pre-treatment and compression ratio on specific gravity (SG) and dimensional stability improvement of three lesser-used wood species from natural forest area of North Kalimantan Province, Indonesia had been investigated. Hot soaking at 80℃ for 3 hours within 2 and 5% of boron solution was applied as pre-treatment, while compression ratio applied was 20 and 40% from the initial thickness. Densification was conducted using hot pressing machine at 30 kg/㎠ of pressure and 160℃ of temperature for 15 minutes. Specific gravity was measured gravimetrically, while dimensional stability was evaluated through thickness swelling and water absorption as the indicator. Results show that SG of densified wood was influenced by wood species and compression ratio, but not by pre-treatment applied; while dimensional stability was influenced by wood species, compression ratio, and pre-treatment. Specific gravity and water absorption of densified wood was improved significantly. Specific gravity increased 28.86-63.03%, while water absorption decreased 12.80-15.89%. Thickness swelling of 20% densified wood was lower than that of 40% densified wood.

• Journal of the Korean Wood Science and Technology
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• 제43권2호
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• pp.196-205
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• 2015

The aim of this study was to evaluate the fuel characteristics of thermally treated wood chips of the Larix kaempferi C. As torrefaction temperature was increased ($200^{\circ}C$ to $300^{\circ}C$), the carbon content, calorific value, and mass loss of torrefied wood chips increased significantly. The torrefied wood chips were shown to have hydrophobic properties even when only treated by mild torrefaction. The energy required to grind torrefied wood chips was reduced by the torrefaction process. Different sizes of wood chips were used in this study; however, this produced almost no difference in the fuel characteristics of processed Larix kaempferi C, except in the distribution of ground wood particles. Similar results were observed when the wood chips were torrefied for different lengths of time (15 min to 60 min) at a constant temperature. Torrefaction was shown to have positive effects on the fuel characteristics of Larix kaempferi C, including improved energy density, storage, and grindability.

• Journal of the Korean Wood Science and Technology
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• 제50권6호
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• pp.375-391
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• 2022

Improving public awareness of wood is crucial for expanding the use of wood and establishing a wood culture. In this study, the environment and trends of the public's wood utilization were analyzed using a questionnaire survey and online text mining at a time when eco-friendly practices are gaining popularity. As a result of reducing climatic and environmental concerns and its positive physical and psychological effects, the use of wood is predicted to rise in areas intimately connected to everyday living, such as wood furniture, wooden structures, and interior materials. Nonetheless, there was a negative awareness that wood was expensive, difficult to maintain, and associated with deforestation. The correlations between wood-related search terms on major Korean portal sites were analyzed and categorized into five groups: Wooden architecture, cultural education, woodworking, wood industry, and wood policy. As a building material, wood was seen as more traditional and friendly than reinforced concrete and stone. Eighty-six percent of respondents expected to utilize wood as a building material in the future, regardless of whether the wood is domestically produced or imported. Sixty-five percent responded favorably about the effects of wood on the health of wooden home inhabitants. It is believed that both active publicity and quantifiable value analysis of human and environmental friendliness are required to increase pro-environment awareness of wood utilization.

• 한국산림과학회지
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• 제94권3호통권160호
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• pp.135-145
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• 2005

본 논문의 목적은 1929년 일제시대 경성부에서 소비된 임산연료의 구성별 특성과 유통경로를 밝히는 것이다. 그 결과를 요약하면 첫째, 1929년 경성부에서 소비된 1호 평균 임산연료의 중량은 경기도의 일반 군에 비해 약 1/3 수준에 불과했으나 열량이 높은 장작과 숯의 소비량은 상대적으로 매우 높았다. 둘째, 임산연료의 최대 공급지는 한강 수운을 이용할 수 있는 강원도와 경기도의 한강변(42.6%)이었고, 그 다음으로 철도를 이용한 경기도 북부와 기타 지역(29.5%), 도로를 이용한 경성부 인근 지역(27.9%)의 순이었다. 셋째, 한강을 이용한 임산연료의 운송지역은 뚝섬(43.0%)과 구용산 마포(45.6%)로 이원화되어 있었고, 철도에 의한 운송은 경성역이 전체의 72.2%라는 압도적인 위치를 차지하고 있었다. 넷째, 경성부의 소비지에 도착한 임산연료의 대부분은 상설시장이 아닌 임시로 형성된 땔감 시장에서 거래되었다.

• 펄프종이기술
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• 제41권4호
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• pp.15-24
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• 2009

This paper estimates the nation wide amount of forest biomass arising from management operation for domestic forest based on the simulations that are composed of five scenarios for selecting the target area of thinning. In 2009, the forest biomass arising from thinning is estimated to be 6,642,174 $m^3$. The estimates of forest biomass in 2015 and 2018 are 5,935,140 $m^3$ and 5,682,538 $m^3$, respectively. Since the target forest for thinning policy is estimated to be decreasing, the biomass generated by thinning will decline too. The estimates of forest biomass can be used to induce more effective application of woody biomass rather than one-sided use such as raw materials for solid fuels including pellets and charcoals.

• Journal of the Korean Wood Science and Technology
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• 제44권3호
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• pp.449-456
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• 2016

본 연구의 목적은 국산 구조용 집성재를 대상으로, 제조과정의 탄소배출을 정량화하고 탄소배출 저감방안을 제시하는 것이다. 총 2개소의 구조용 집성재 제조업체를 대상으로 원료, 수송, 제조 공정, 제조에 의한 에너지소비량 등을 현장 실사하였다. 현장에서 수집한 자료 및 구축된 전과정목록과 같은 관련문헌을 토대로 단위부피당 탄소배출을 정량화하였다. 국산 구조용 집성재의 제재 및 건조, 집성 공정별 온실가스 배출결과는 각각 31.0, 109.0, 94.2 kg $CO_2eq./m^3$으로 나타났다. 수입 구조용 집성재와 비교하였을 때 약 13% 온실가스를 적게 배출하는 것으로 나타났다. 또한 기존의 건조 에너지원을 바이오매스로 전환시에는 기존 대비 37%의 온실가스를 감축하여 친환경성을 제고할 수 있을 것으로 판단되었다. 본 결과는 향후 목조주택의 환경성을 규명하기 위한 전과정평가 수행 시, 투입된 목재제품의 전과정목록분석을 위한 기초자료로 활용될 것으로 기대된다.

• 임산에너지
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• 제25권2호
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• pp.1-8
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• 2006

안동 봉정사 대웅전의 지붕구조로 사용되었던 해체부재와 새로이 벌채된 소나무재의 물리적, 기계적, 화학적 특성을 평가 분석하였다. 고목재의 해부학적 분석에 의해 만재부위에서 수지의 응고현상을 관찰할 수 있었다. 또한 열화에 의한 비중의 감소, 가도관의 미세할렬이 발생하였으며, 가도관 미세할렬은 S2층 마이크로휘브릴 경사각과 동일한 각도를 갖는 것으로 판단되었다. 고목재의 휨강도, 압축강도 및 전단강도는 모두 35-27% 가량 감소하였으며, 초음파 비파괴시험에 의한 동적탄성계수는 목재의 사용기간이 길어짐에 따라 감소하는 경향을 나타내었다. 목재의 열화는 비중과 동적탄성계수의 측정으로 확인할 수 있었다. 또한 길이방향 동적탄성계수의 측정으로부터 기계적 성능의 예측이 가능하였다. 목재의 부후를 판정할 수 있는 1% NaOH 추출 결과 고목재에서 부후가 많이 진행되었음을 확인하였다. 이에 따라 목재의 열화는 화학조성분의 분석에 의해 평가가 가능할 것으로 판단되었다. 이 연구의 결과는 시간의 경과에 따른 소나무의 물성 변화 분석으로부터 장기적으로 사용하는 목재의 물성 변화를 이해하고 예측을 가능하게 하는 자료의 활용될 수 있을 것이다.

• Journal of the Korean Wood Science and Technology
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• 제35권6호
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• pp.13-22
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• 2007

주요 조림수종으로 도입 식재된 리기다소나무의 고부가가치 이용을 위한 구조용 집성재 이용 가능성을 검토하고, 이에 적합한 기술을 개발하기 위하여 본 연구를 수행하였다. 국산 리기다소나무 제재목의 기계응력등급은 대부분 E7에서 E9등급으로 집성재 제조에는 다소 불량한 것으로 나타났다. 반면 단일수종 및 혼합수종 구조용 집성재 제조에 필수적인 리기다소나무 및 낙엽소 판재의 접착성을 평가한 결과 전단접착력, 목파율, 침지 및 삶음박리율 모두 KS기준 이상으로 나타났다. 리기다소나무 단일수종 집성재의 휨성능을 측정해본 결과 휨강도는 KS의 집성재 강도등급에 따른 휨성능 합격기준을 만족한 반면 휨 탄성계수는 기준에 다소 못 미치는 결과를 나타내었다. 그러나 낙엽송 층재와의 혼합구성을 통해 리기다소나무 집성재의 휨성능(휨강도와 휨탄성계수)을 20% 향상시킬 수 있었으며, 층재 구성방법에 있어서는 판재의 탄성계수가 높고 품질이 우수한 낙엽송 층재를 외층에 배치하는 방법이 보다 효과적인 것으로 확인되었다. 결론적으로 리기다소나무의 부가가치 증진을 위한 구조용 집성재 이용은 그 가능성이 매우 컸다.

• 펄프종이기술
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• 제37권3호
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• pp.41-49
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• 2005

Styrofoam as shock-absorbing materials for packaging has been regarded as one of non-biodegradable products leading to soil contamination at a landfill and release of dioxine during its incineration. For avoiding severe burdens on our environments by styrofoam, it must be replaced by environment-friendly materials. In order to evaluate availability of pulp fibers as a substitute for styrofoam, various extrusion processes were applied for making optimal biodegradable products. Then thermomechanical pulp fibers made of Pinus radiata and Pinus rigida were uniformly mixed with other additives such as starch and polyvinyl alcohol prior to expansion. The physical properties of the final products were examined by measuring expansion efficiency, compression strength, and elastic modulus. Wheat starch played a key role to maintain optimal flowing conditions within the barrel of the extruder irrespective of addition of soluble starch and polyvinyl alcohol. However, as the amounts of wheat starch in raw-materials increased, the elastic modulus of the expanded materials greatly increased. High elastic modulus is not suitable as shock-absorbing products for packaging. Thus the wheat starch must be added at a minimum if possible, that is, below 20% based on oven-dried weight of pulp fibers. the elastic modulus of the expanded products was decreased as their moisture contents increased. For the products containing 20% wheat starch, the lowest elastic modulus, 844.64 kPa was obtained under 10% of the moisture content. This was similar to that of styrofoam.

• Journal of Forest and Environmental Science
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• 제35권4호
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• pp.272-280
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• 2019

Forest medicinal resources, which constitute one of the non-timber forest products, have been regarded as healthy and highly valued products. To meet the increasing demand of the medicinal resources, it is necessary to improve the propagation methods of medicinal plants. In vitro propagation not only allows an opportunity for propagating plants in large numbers but also allows for enhancing the quality and quantity of the desired functional component of a plant by altering the growth factors, such as medium, carbon source, and plant growth regulators influence plant. There have been several studies of in vitro propagation methods, such as axillary bud culture, shooting, and embryogenesis, on Kalopanax septemlobus, Eleutherococcus sessiliflorus, Hovenia dulcis, and Schisandra chinensis in Korea between from 2000 through 2010. Furthermore, there have been attempts to proliferate callus and plantlets for producing useful natural compounds by using bioreactors. Here, we provide an account of the in vitro propagation methods of medicinal trees in Korea based on a review of several micropropagation studies.