• Journal of the Korean Wood Science and Technology
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• v.50 no.1
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• pp.1-11
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• 2022

To evaluate the bearing strength of red pine cross-laminated timber (CLT) with self-tapping screw (STS), which is widely used as a fastener for connection in CLT building, the bearing test was conducted. Accoring to the STS's diameters (8, 10, 12 mm), the bearing test specimens with half hole were manufactured. Bearing strength was compared and reviewed in consideration of the configuration in STS and the loading direction to the grain of red pine. As a result of the bearing test on the STS's diameter, the yield bearing load increases as the larger diameter of the STS in all directions of the red pine. The bearing strength of the thread part (thread + tip) was higher than the shank part (shank + shank cutter). In compared with the directions to the grain of red pine, the bearing strength of the cross section parallel to the loading direction was the highest, and the tangent section was the lowest bearing strength. The average bearing strength of the loading direction in parallel to the grain was 23.43 MPa, which was about 45% higher than the average 16.16 MPa in perpendicular to the grain. The predicted bearing strength calculated by Eurocode (EN) and Korean Building Code (KBC)'s equation was lower than the experimental value. It is nessesary to propose the new equations of bearing strength reflected the configuration information of STS.

• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.200-207
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• 2009

As an effort to utilize the pine woods damaged by pine wilt disease, this study analyzed the density of pine wood nematode and compressive strength of damaged trees treated through soaking and fumigating. The density of nematode in Pinus densiflora and Pinus thunbergii woods soaked in wood vinegar and nematicide, and in seawater reduced greatly in 21 days and in 30 days, respectively. When reextracted nematode was injected artificially into healthy trees, infection was not observed after the lapse of six months, and the mean density of Pinus densiflora and Pinus thunbergii was $0.47g/cm^3$ and $0.54g/cm^3$, respectively, and their compressive strengths were $304kgf/cm^2$ and $363kgf/cm^2$, respectively. As to change in the density of pine wood nematode after fumigating, pine wood nematode was detected until the third month in both species, and those detected afterwards were found to be similar nematodes. After 24 months, the mean densities of Pinus densiflora and Pinus thunbergii were $0.54g/cm^3$ and $0.52g/cm^3$, respectively, and their compressive strengths were $353kgf/cm^2$ and $370kgf/cm^2$, respectively.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.851-860
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• 2015

The objective of this study was to manufacture the wood based roughage using lumber from thinning of oak and pitch pine (Pinus rigida). And the study also aimed to investigate a feed value evaluation of wood based roughages. To investigate the optimization condition of steam-digestion treatment for roughage, the wood chips of oak and pitch pine were steam-digestion treated at $160^{\circ}C$ under pressure 6 atm depending on treatment times (60 min, 90 min and 120 min) followed by the content of essential oils analyzed. The essential oil content of steam-digestion treated roughages for 90 min and 120 min were under 0.1 mL/kg. The evaluation of feed value was carried out from steam-digestion treated roughages for 90 min through feed chemical composition analysis, NRC (National research Council) modeling, ruminal degradability analysis and relative economic value analysis. The feed chemical compositions including DM (dry mater), CP (crude protein), EE (ether extract), NDF (neutral detergent fiber), ADF (acid detergent fiber), ADL (acid detergent lignin), NFC (nonfiber carbohydrate) in oak roughage were 95.4, 1.36, 3.11, 90.05, 83.85, 17.33, 6.50%, respectively, and in pitch pine roughage were 94.37, 1.33, 5.48, 87.89, 86.88, 30.56, 6.32%, respectively. Both roughages showed low level of protein and very high level of NDF. The TDN (total digestible nutrient) levels using NRC (2001) model in oak and pitch pine roughages were 40.55, 31.22%, respectively. The ruminal in situ dry matter degradability was higher in oak roughage (23.84%) than in pitch pine roughage (10.02%). The economic values of oak and pitch pine rough-ages were 235, and 210 \, respectively.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.370-380
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• 2016

The black pine logs damaged by pine wilt disease in Jeju-do were heat-treated to extend the utilization of domestic trees damaged by pine wilt disease. The heat-treatment of wood requires wood to be heated to $56^{\circ}C$ for 30 min at the core. The average moisture content and top-diameter of the black pine logs were ranged from 46% to 141% and from 180 mm to 500 mm, respectively. And the basic specific gravity and oven-dry specific gravity of the black pine logs were 0.47 and 0.52, respectively. The time required for heat-treatment at $105^{\circ}C$ temperature was ranged from 7.7 h to 44.2 h, depending on moisture content and top-diameter. The temperature distribution was used to predict the time required for heat-treatment of black pine log with various moisture contents and top-diameters using finite difference method. The thermal properties of wood including the thermal conductivity and specific heat in accordance with moisture content were calculated. Heat transfer coefficient for mixed convection in form of adding natural convection and forced convection was used for heat transfer analysis. The error between the measured and predicted values ranged from 3% to 45%. The predicted times required for heat-treatment of black pine log with 50% moisture content and 200 mm, 300 mm, and 400 mm top-diameter were 10.9 h, 18.3 h, and 27.0 h, respectively. If the initial moisture content of black pine log is 75%, heat treatment times of 13.6 h, 22.5 h, and 32.8 h were predicted in accordance with top-diameter. And if the initial moisture content of black pine log is 100%, heat treatment times of 16.2 h, 26.5 h, and 38.2 h were predicted in accordance with top-diameter. When the physical properties of logs damaged by pine wilt disease are presented, these results can be applicable to the heat-treatment of red pine and Korean pine logs as well.

• Journal of the Korean Wood Science and Technology
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• v.40 no.3
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• pp.194-203
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• 2012

1-Ethyl-3-methylimidazolium acetate known as efficient biomass pretreatment reagent was used for the extraction of lignin from rigida pine wood (pitch pine), which was called to ionic liquid lignin (ILL), and chemical structural features of ILL were compared with the corresponding milled wood lignin (MWL). The amounts of phenolic hydroxyl groups (Phe-OH) was determined to 10.0% for ILL and 7.2% for MWL, respectively, where those of methoxyl groups (OMe) were 4.9% for ILL and 11.0% for MWL, respectively. The weight average molecular weight (Mw) of ILL (3,995) were determined to ca. 1/2 of that of MWL (8,438) and polydispersity index (PDI: Mw/Mn) suggested that the lignin fragments were more uniform in the ILL (PDI 1.36) than in the MWL (PDI 2.64). The temperature (Tm) corresponding to maximum decomposition rate (Vm) of ILL ($306.6^{\circ}C$) was ca. $35^{\circ}C$ lower than that of MWL ($341.9^{\circ}C$), suggesting that ILL was thermally unstable than MWL, as evidence from the lower Tm for ILL. Moreover, the structural characteristics of ILL and MWL were confirmed by spectroscopic analyses (FT-IR and $^{13}C$-NMR), and these results indicated ionic liquid (1-ethyl-3-methylimidazolium acetate) was chemically or physically bound to ILL.

• Journal of the Korean Wood Science and Technology
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• v.35 no.2
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• pp.79-84
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• 2007

Surface mold fungi growing on CCA-treated wood could be inhibited effectively by the incorporation of moldicide into treating solution. In this study, moldicides compatible with the CCA solutions from various commercial moldicides were screened, and then their optimum concentrations for controlling surface mold on CCA-treated radiata pine sapwood were examined through both the laboratory and the field trials. Among nine commercial moldicdes tested, two substituted isothiazolinones, moldicide A containing 2-n-octyl-4-isothiazoline-3-one and moldicide B containing 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one, were chemically compatible with CCA solution. The optimum concentration to be incorporated into 2% CCA treating solution was determined to be 0.001% for moldicide A and 0.003% for moldicide B.

• Journal of the Korean Wood Science and Technology
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• v.27 no.4
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• pp.30-37
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• 1999

The effects of heat treatment on the dimensional stability and bending properties of radiata pine sapwood were investigated. The dimensional stability was almost achieved by heat treatment though the loss of strength was accompanied as a negative effect. The improvement in dimensional stability of wood and the resultant reduction in bending properties were closely related to treatment temperature and duration. The optimum treatment conditions, which could be used to achieve a desired improvement in dimensional stability with resultant losses in modulus of rupture were proposed based on the results obtained in this study.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.56-65
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• 2016

Pine wood nematode, Bursaphlenchus xylophilus is a fatal damaging pest, infecting pinewood trees and is one of the serious forest pest in Korea. Trunk injection is one of the most effective method to protect the live pine trees from nematode infection. The aim of this research was to reveal the efficacy of the nematicidal materials from 46 Kyrgyzstan, 88 Vietnam plant materials and 21 active materials (${\alpha}$-terpinene, ${\alpha}$-pinene, ${\beta}$-thujaplicin, cinnamaldehyde, eugenol, emodin, geraniol, limonone, methyl palmitate, matrine, myrcene, methyl gallate, nicotine, quassin, resveratrol, rotenone, thymol, thujaplicin, terthiophene, tuberstemonine, ${\gamma}$-terpinene) isolated from plants for using as trunk injection agents. Eclipta prostrata extract was highly effective against pine wood nematode in plant extracts and terthiophene has the best nematicidal activity from active materials isolated from plants. Foliar spray of terthiophene on Japanese black pine (Pinus thunbergii) tree reduced proliferation of inoculated pine wood nematode at 22 days after treatment, however no efficacy was found over 22 days. Eclipta prostrata extract and terthiophene can be used as nematicide for further nematicidal efficacy test against any other plant parasitic nematodes and trunk injection efficacy against pine wood nematode.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.1
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• pp.27-36
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• 2007

Milled Korean pine (Pinus densiflora) wood was used to evaluate its adsorption capacity of Cu(II) ions from aqueous solution by running a series of batch experiments. Prior to the tests, the milled woods were pretreated with 1N NaOH, 1N $NHO_3$, and distilled water, respectively, to examine the effect of pretreatment. Within the tested pH range in this study between 3 and 6, copper adsorption efficiency of NaOH-treated wood(96~99%) was superior than $NHO_3$-treated wood(19~31%) and distilled water-treated wood(18~35%). Adsorption behavior of copper onto both raw and $NHO_3$-treated woods was mainly attributed to interaction with carboxylic acid group. For NaOH-treated wood, carboxylate ion produced by hydrolysis was a major functional group responsible for Cu sorption. NaOH treatment of wood changed the ester and carboxylic acid groups into carboxylate group, whereas $NHO_3$ treatment did not affect the production of functional groups which could bind copper. A pseudo second-order kinetic model fitted well for the sorption of copper ion onto NaOH-treated wood. A batch isotherm test using NaOH-treated wood showed that equilibrium sorption data were better represented by the Langmuir model than the Freundlich model.

• The Korean Journal of Mycology
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• v.46 no.1
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• pp.34-42
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• 2018

Tricholoma matsutake (Pine mushroom) is expensive, and its artificial cultivation has been tried in several countries. Until date, the only successful cultivation of artificial pine mushroom in pine forests uses matsutake-infected pine trees. The National Institute of Forest Science in Korea has been restudying this method since 2000. Success in fruit production and reproduction was achieved in 2010 and 2017, respectively, in the same locale. The successes proved that pine mushrooms could be cultivated artificially in the field using matsutake-infected pine trees. The fruiting of pine mushroom in October 2010 occurred 6 years, 6 months after the transplantation of matsutake-infected pine trees. Five pine mushrooms reoccurred in September 2017, 13 years, 5 months and 15 years, 5 months after the transplantation of the respective matsutake-infected pine trees. The distance between the matsutake-infected pine tree and the pine mushrooms was 12 cm at 6.6 years, 90~115 cm at 13.5 years, and 95 cm at 15.5 years. Fruiting bodies occurred 13~16 days after the underground temperature declined to below $19^{\circ}C$. In conclusion, the use of matsutake-infected pine trees remains the only way to artificially cultivate pine mushrooms. More knowledge of the environmental factors affecting matsutake fruiting would be beneficial.