• Journal of the Korean Wood Science and Technology
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• 제48권1호
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• pp.1-11
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• 2020

Indonesian log production is dominated by young trees harvested from plantation forests. The timber contains of sapwood and juvenile wood, which are not resistant to termite attack. Smoking treatment can enhance wood resistance to termite attack, but it also changes the color. Specimens of mangium (Acacia mangium) and sengon (Falcataria moluccana) wood were exposed for 1, 2, and 3 weeks to smoke produced from the pyrolysis of salam (Syzygium polyanthum) wood. The color change of the wood was measured using the CIELab method. In addition, wood specimens were exposed to subterranean termites (Coptotermes curvignathus Holmgren) under laboratory conditions. Untreated and imidacloprid-preserved wood samples were also prepared for comparison purposes. The results showed that the color of smoked wood differed from that of untreated wood, and the color change for sengon was greater than for mangium. In addition, the 1-week smoking period changed the wood color less than the 2- and 3-week periods, which did not differ. Imidacloprid-preserved wood had distinctive color changes compared to untreated wood. Untreated mangium wood had moderate resistance to subterranean termite attack (resistance class III), while sengon had very poor resistance (resistance class V). Salam wood smoke enhanced wood resistance to termite attack, and smoke treatment of 1 week for mangium and 2 weeks for sengon resulted in the wood becoming very resistant (resistance class I). Both types of smoked wood were more resistant to subterranean termite attack than imidacloprid-preserved wood (average class II resistance).

• Journal of the Korean Wood Science and Technology
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• 제47권4호
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• pp.451-458
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• 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.

• Journal of the Korean Wood Science and Technology
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• 제34권5호
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• pp.88-97
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• 2006

Wood flour (WF)-recycled polypropylene (RPP) composites composed of 50% WF of Eucalyptus deglupta Blume species, 50% RPP, various contents of maleic anhydride (MAH) modifier (0; 1; 2; 5; 5; 7.5; and lo%), and 15% dicumyl peroxide (DCP) initiator (based on MAH weight) were subjected to weather for 1 year and subterranean termite (Coptotermes cuwignathus HOLMGREN) and dry wood termite (Cryptotermes cynocephalus LIGHT) for 3 and 4 weeks, respectively. WF-RPP composites with 2.5% MA modifier had tensile strength, breaking elongation and Young's modulus about 2.2, 2.3, and 1.2 times, respectively higher compared to MAH-free composites. The WF-RPP composites with or without MAH modifier had 5.5 times higher resistance to weather compared to RPP film alone. The color of the WF-RPP composites with or without MAH modifier became lighter after exposures to the weather. The WF-RPP composites with or without MAH modifier are resistant to subterranean termite Coptotermes curvignathus HOLMGREN and dry wood termite Cryptotermecs cynocephalus LIGHT under the experimental condition adopted.

• Journal of the Korean Wood Science and Technology
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• 제46권6호
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• pp.748-755
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• 2018

Timber from fast-growing tree species is susceptible to by biodeterioration attack, particularly subterranean termites. Impregnation with methyl methacrylate (MMA) potentially increases wood resistance to subterranean termite attack. Four wood species, namely sengon (Falcataria moluccana), jabon (Anthocephalus cadamba), mangium (Acacia mangium), and pine (Pinus merkusii), were impregnated with MMA, and samples of untreated and imidacloprid-preserved wood were prepared for comparison purposes. Small stakes, sized 0.8 cm by 2 cm in cross section by 20 cm in the longitudinal direction, were inserted into the ground for 3 months, and the weight loss of each specimen was determined at the end of the test period. A factorial $4{\times}3$ completely randomized design was used for data analysis; the first factor was wood species, and the second factor was treatment. The results showed that MMA polymer loadings were 27.88%, 24.91%, 14.14%, and 17.81% for sengon, jabon, mangium, and pine, respectively, and amounts of imidacloprid retention were $7.56kg/m^3$, $5.98kg/m^3$, $5.34kg/m^3$, and $9.53kg/m^3$, respectively. According to an analysis of variance, wood species, treatment, and interaction of both factors significantly affected the weight loss of wood specimens. Mangium had the smallest weight loss, followed by pine, sengon, and jabon. MMA impregnation into the wood increased the resistance of wood samples to subterranean termite attack during in-ground testing, but the resistance level was lower than that of imidacloprid-preserved wood. Except for mangium wood, the MMA treatment did not significantly affect resistance.

• Journal of the Korean Wood Science and Technology
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• 제43권2호
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• pp.248-257
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• 2015

This research focused on the natural durability of twenty one lesser known tropical wood species planted in West Java, Indonesia against subterranean termite (Coptotermes curvignathus). It was observed that both heartwood and sapwood of Kiara payung (Filicium decipiens); heartwoods of Nangka (Arthocarpus heterophyllus), Mahoni (Swietenia macrophylla) and Simpur (Dillenia grandifolia); and sapwood of Bungur (Lagerstroemia speciosa) were rated as resistant (natural durability class II) according to Indonesian standard SNI 01.7207.2006 (BSN 2006). Both heartwood and sapwood of Salam (Syzigium polyanthum), Pasang (Lithocarpus sundaicus), Bisbul (Diospyros discolor), Rukam (Flacourtia rukam) and Trembesi (Samanea saman); heartwood of Puspa (Schima walichii), Bungur, Tanjung (Mimusops elangi) and Angsana (Pterocarpus indicus) were rated as moderately resistant (natural durability class III). Both heartwood and sapwood of Sungkai (Peronema canescens), Pine (Pinus merkusii), Mangium (Acacia mangium) and Afrika (Maesopsis eminii); sapwoods of Mahoni, Puspa and Tanjung were rated as poorly resistant (natural durability class IV). Both heartwood and sapwood of Agathis (Agathis dammara), Durian (Durio zibethinus), Ki sampang (Evodia latifolia) and Jabon (Anthocephalus cadamba); sapwoods of Nangka and Angsana were rated as very poorly resistant (natural durability class V). This reserach showed that woods with lower resistance against C. curvignathus attack (natural durability class IV and V) tend to have lower termite mortality values compared to woods with higher resistance against C. curvignathus attack (natural durability class II and III). Results of the study will provide some valuable information on termite resistance of twenty one lesser known tropical wood species planted in Indonesia.

• Journal of the Korean Wood Science and Technology
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• 제34권2호
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• pp.1-9
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• 2006

The structural wooden members of the ancient building are deteriorated by fungi and termite over time. The deteriorate of the members causes the decrease of the specific gravity and the strength of it, so the stability of the building is threatened. Therefore, in this study, the evaluation of the specific gravity, which is correlated with the strength of the wood, was conducted in the post member using Nondestructive Evaluation (NDE) - Drilling Resistance Test (DRT). For the purpose of it, the specific gravity and drilling resistance of small specimens was measured to obtain the correlation between the specific gravity and the drilling resistance. And then, the drilling resistance test of the post members, which were expected to have the deteriorated parts, was performed. Consequently, the correlation between the specific gravity and the drilling resistance was very high ($R^2=0.89$) and the distributions of the specific gravity were evaluated for the each member. Also, the results were verified by the visual inspection of the cross section of it. Especially, the various variations of the wood member such as the deteriorated parts with termite or fungi and the crack could be detected exactly but the knot couldn't because the drill could pass by or could not penetrate the knot.

• Journal of the Korean Wood Science and Technology
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• 제49권1호
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• pp.82-92
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• 2021

Nakdong technique is an unfamiliar scorching treatment using an iron heated in a kiln over 1000℃. It is a typical convention in Asian countries to treat Nakdong on the surface of paulownia species. The scorching treatment changes the surface characteristics as well as the color of the wood. This study focused on the effects of functional features such as water resistance, anti-mold, anti-termite, and sound improvement because this treatment is usually used on paulownia wood-bodied musical instruments surface. It took 28'57" for Nakdong-iron treated surface to absorb a droplet of water. The absorbance time of iron treated surface was longer than that of torch treated one. There was no noticeable effect on the anti-mold test. On the anti-termite test, there was nearly 3% more mean mass loss on the torch samples than controlled and iron treated ones. In examining the sound radiation coefficient before and after Nakdong treatment, the Nakdong-iron treated surface showed an increase in the average value of 1.2 m4/kg s, which means that it has sound quality improvement. Through this research, the Nakdong technique results are expected to be used as basic-data for further research and give a practical idea for using the traditional treatment method on the wood surface.

• Journal of the Korean Wood Science and Technology
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• 제46권4호
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• pp.323-337
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• 2018

Merkusii pine wood (Pinus merkusii) was extensively planted throughout Indonesia, where it is only indigenous in northern Sumatera, by the Dutch during colonial times. The demand for this wood species, especially in the domestic market, has increased notably, despite its limited durability regarding decay resistance. The purpose of this study was to investigate the occurrence of juvenile and mature wood on merkusii pine and to analyze its radial features from pith to bark based on density, shrinkage, static bending in modulus of rupture and modulus of elasticity, fiber length, microfibril angle, and durability. A segmented modeling approach was used to find the juvenile-mature transition. The graveyard test was performed to characterize the termite resistance from pith to bark of merkusii pine. The maturations were estimated to start at radial increments of 15 cm from the pith by fiber length and of 12 cm from the pith by microfibril angle. The projected figures for the proportion of juvenile wood at breast height were around 65%. The results also indicate that the pine wood was $0.52g/cm^3$ in density, 1.45 in coefficient of anisotropy, which indicates its good stability, 7597 MPa in modulus of elasticity, and 63 MPa in modulus of rupture. Natural durability against subterranean termite of the merkusii pine wood was rated to be grade 4 to 0 from pith to bark. However, after being treated by Entiblu and Enborer preservatives, its rating increased to grade 10 to 9.

• Journal of the Korean Wood Science and Technology
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• 제40권6호
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• pp.370-377
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• 2012

잣나무(Pinus koraiensis S. et Z.)와 로지폴소나무(Pinus contorta Dougl)를 이용하여 열처리 목재를 제조한 후 처리조건에 따른 재색변화를 조사하였다. 반응표면분석법에 따라 설정된 9가지 처리조건(처리온도 : 170, 180, 200, 220, $230^{\circ}C$, 처리시간: 90, 120, 180, 240, 270 min.)에서 열처리 시편들을 제조하였으며, 색차계를 이용하여 재색을 측정한 후 흰개미 저항성을 평가하기 위하여 진주에 설치된 흰개미 시험장에서 6개월 동안 야외노출시험을 실시하였다. 처리온도와 처리시간이 증가함에 따라 명도가 감소하였으며 감소폭은 시간보다 온도에 의한 영향이 더 큰 것으로 나타났다. 미국국립표준국(National Bureau of Standards : NBS)에서 제시된 방식에 의해 평가된 색차를 처리온도와 처리시간의 함수로 표현한 반응표면분석모델은 잣나무의 경우 $R^2$의 값이 0.92, 로지폴파인의 경우 0.88로 열처리조건에 따른 색채의 예측가능성을 보여주었다. 6개월의 야외시험결과 열처리 조건에 상관없이 흰개미 가해가 심하게 발생된 것으로 나타났는데, 이는 제조된 열처리 목재의 흰개미 저항성이 야외에 사용하기에 적합하지 않다는 것을 보여준다.

• Journal of the Korean Wood Science and Technology
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• 제45권1호
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• pp.12-19
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• 2017

황장목(黃腸木)은 적황색을 띠는 심재부의 비율이 높고 연륜폭이 매우 조밀하며 최소 수령이 100년 이상 되는 귀중한 소나무 자원이다. 조선시대에는 황장목을 궁궐, 사찰 등 중요 건축물에 사용하였다. 하지만 황장목의 재질특성에 관한 연구는 매우 부족한 실정이다. 본 연구에서는 황장목의 천연내구성을 검토하기 위하여 부후균 및 흰개미 저항성을 조사하였다. 공시균은 갈색부후균(Fomitopsis palustris)과 백색부후균(Trametes versicolor) 균주를 사용하였고, 공시 흰개미는 일본흰개미(Reticulitermes speratus)를 사용하였다. 그 결과, 갈색 및 백색부후균에 의한 중량감소율은 심재부에서 3.7~5.6%, 변재부에서는 16.1~26.3%로 나타났다. 또한, 흰개미 사충률은 심재부에서 약 47%로 매우 높게 나타났다. 이러한 결과를 통하여 황장목의 심재부는 부후균 및 흰개미에 대한 저항력이 뛰어난 것을 알 수 있었다.