• Journal of the Korean Wood Science and Technology
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• v.36 no.1
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• pp.36-44
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• 2008

It is necessary to assess wood quality and strength of the clear specimens from used members in old wooden structures for the reuse of old members on the same structure or a new structure. Wood species classification by microscope observation of each wood member that was used in truss cord and temple, and several physical and strength tests by the specification of present KS standards were conducted to compare with some references. From the comparison of strengths with references, Korean larch gives relatively better wood quality and mechanical properties than other wood species. No significant deterioration of cell wall was found by microscopic observation for the sound wood part that was selected visually. Tensile specimens with 3 mm in thickness on the middle span showed greater strength than 5 mm thick specimens, which explains that dimension of tensile specimen should be examined for evaluating precise tensile strength properties. Other tests, compression, shear, and bending, are adoptable for each strength properties. Test methods for the evaluation of basic strengths and fastener connections for old wood species should be further examined.

• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.1-8
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• 2006

The physical, mechanical and chemical properties of old and new Korean red pine (Pinus densiflora) were analyzed. The old woods were from dismantled timbers of Bonjungsa temple. The crystallized resin in the latewood was observed by microscopic analysis. Also, reduction of specific gravity, occurrence of microscopic cleavage of tracheid was observed in the old wood. The angle of microscopic cleavage of tracheid is estimated with the same angle of micro-fibril angle of 52 layer. The bending, compression and shear strength of old world were decreased about 35-27% than those of new wood. Dynamic modulus of elasticity measured by ultrasonic nondestructive test has the tendency of reducing by the time elapse of the wood usage. Therefore, deterioration of wood could be measured by reduction of specific gravity and dynamic MOE. The static MOE and mechanical properties of old wood could be predictable by measuring dynamic MOE in the longitudinal direction. Extractives of the old wood in 1-% NaOH solution are larger quantity than new wood. Therefore the decay of the wood could be evaluated by analyzing the chemical compound, especially 1-% NaOH solution. The results of this research could be used for understanding and prediction of the changing properties with elapsing time of wood.

• Journal of the Korean Wood Science and Technology
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• v.48 no.5
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• pp.618-630
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• 2020

Muna teakwood, especially from old stands, has been popular as raw material for timber industries in Indonesia for the past ten decades. Due to the scarcity of this wood, superior-grown seedlings of Muna teakwood have been developed and widely planted. Since there is no information on its characteristics, therefore, the aim of this research was to investigate wood characteristics of the 8-year-old superior-grown teak from Muna Island to ensure their proper utilization as raw material for wooden furniture. Wood discs and boards from basal area of three different trees were used as the samples. Macroscopic and microscopic anatomical characteristics were observed following the IAWA's list, while their physical-mechanical properties were measured following British Standard 373-57. Results showed that anatomical characteristics of this wood sample are similar to regular teakwood, but its heartwood portion is higher. Differences among trees are found in regards to wood texture, growth ring width, as well as early and latewood portion. The green moisture content was lower than that of fast-growing teak of a similar age. The wood is more stable than the old teakwood, but its specific gravity is lower. In general, mechanical properties of this wood were higher than those of the regular fast-growing teakwood, but lower than the old one. Based on its specific gravity, this superior Muna teakwood was categorized as a Strength Class of III. The wood is suitable enough for wooden furniture manufacturing.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.168-179
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• 1982

The first step to utilize the growing resources of Italian poplar (Populus euramericana I-476) for pulp-Woods, its characteristics and adaptabilities to the pulp industry must be investigated completely. The plantation methods are important for its fast growing in stock, and no less important is the cutting age for its utilization as pulpwood. In this paper, the stone groundwood pulping, refiner groundwood pulping and chemi-groundwood pulping characteristics by the age of tree, along with their physical and chemical characterstics were tested, and relationships between the age groups were analyzed to find out the optimum felling age. The results obtained are as follows: 1. The coefficient of pliability was a little higher in the case of younger trees. 2. The water retention value of each pulp was directly proportional to its physical strength, but this tendency was not detected between the age groups of sample woods. 3. Generally, the physical strength of younger wood pulp was lower regardless of the pulping process. But in the case of pretreatment with NaOH, Asphund and CGP pulp from 5 year old sample wood were stronger in physical strengths than those of GP and Asplund pulp with no pretreatment from 10 years old sample wood. 4. The tear factor of Asplund pulp with alkali pretreatment was higher than that of CGP pulp but the breaking length and the burst factor was similar in all processes. Considering the pulp yield and its brightness, CGP process seems to be advantageous. 5. The dissimilarity of physical strength between 7 and 10 years old wood pulp was not very large in all pulping processes but the physical strength of 5 year old wood pulp was very weak. In the of groundwood pulping from Italian poplar woods, 5 year old wood pulp should be mixed with other long fiber pulp for making a good paper.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.74-81
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• 2004

The ultrasonic non-destructive method was used for wood decay test. The temperature change and moisture contents of wood were estimated how the ultrasonic wave velocity changes. The relationship between weight loss of wood decayed by T. palustris and ultrasonic wave velocity was investigated. The non-destructive methods of different condition of logwood were estimated. Decay map of old wood was made by non destructive methods. Through these tests, we can accumulate the data to judge the degree of wood decay. The decay map of wood could be used for the analysis of old wood.

• Korean Journal of Poultry Science
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• v.32 no.2
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• pp.101-106
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• 2005

This study was designed to estimate effect of wood vinegar on meat quality in old Layer which was low production and low economic value. The old layer chickens were used to resource for income increase of layer farm and protein supply. Two hundred forty Isa Brown chickens were assigned with control(Broiler feed), Treatment 1 (Broiler feed with addition of domestic wood vinegar $0.8\%$) and Treatment 2(Broiler feed with addition of foreign wood vinegar $0.4\%$). Feed intake of control group was lower 3g than other treatments. This is the reason of result that what organic acid in wood vinegar of treatment groups affect to feed digestibility, The different of chicken production was depended on ingredient and included value of wood vinegar in domestic and foreign. Foreign wood vinegar have organic acids which that functionally act sexual Pheromone so that promote endocrine matter. This is reason that old Layer chicken increase to egg production rate. Treatment 2 group effect to thigh meat rather than breast meat and improve to value of crude fat and meat color. The Meat quality and sensory test of thigh meat of foreign wood vinegar was better appraise rather than that of domestic wood vinegar. Because foreign wood vinegar make to fine of meat tissue and to decline cooking loss and also to increase juiciness and tenderness on sensory test.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.2
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• pp.99-105
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• 2016

The increase of wet web solid content after wet press and dry compressive strength were observed in lab study by judicious application of wood flour and starch for the old corrugated container (OCC). Pearl starch was better than cationic starch in strength development, but cationic starch was better for drainage. Application of vacuum on the mixed solution of wood flour and starch helped strength development further without loss of other properties. The effect of wood flour addition on wet web solid content improved as the wet pressing pressure increased. The use of wood flour and starch mixture improved wet web solid contents further.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.5
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• pp.12-17
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• 1999

This study was to evaluate applications of the alkalophilic enzymes from Coprinus cinereus 2249 with old newsprint(ONP). A enzymatic deinking process based on alkalopholic enzymes was investigated . It was found that alkalophilic enzymes could effectively deink old newsprint. When applied on deinking of the old newsprint, it increases the freeness and brightness due to effect of hydrolysis at 0.1% enzyme concentration . Also, the physical properties of deinked pulp were improved.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.566-577
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• 2015

White Jabon (Anthocephalus cadamba Miq.) is one of the fast growing species in Indonesia and has the potential as the raw material for pulp and paper. In this research, 3, 5, and 7 years old White Jabon woods were pulped under different active alkali charge of 15%, 18%, 21%, 24%, and 27%, and its effect on delignification degree, kappa number, pulp yield, pulp viscosity, brightness, unbeaten freeness, and delignification selectivity was investigated. The results showed that tree age and active alkali concentration influenced the quality of pulp and pulping properties, except for that of unbeaten freeness. Delignification degree increased with increasing active alkali charge, and this brought about the decrease of pulp kappa number. The pulping yield tended to decrease below the Klason lignin of approximately 4%. Even though the 3 years old wood resulted in the highest brightness and highest delignification selectivity, the highest pulp viscosity was obtained with the 5 years old wood. The dominant fiber length of all wood ages was in the range of 1.2 - 2.0 mm. The 3 years old wood was considered to be the most promising raw material for kraft pulping in the view point of pulping properties, pulp quality and harvesting rotation.

• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.193-206
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• 2014

Residual performance of old architectural wood which has been damaged was measured using Nondestructive Evaluation (NDE). The wood Pole Tester was used to assess ultrasonic velocity inside wood and drill resistance was determined using an IML-resistograph. For ultrasonic measurements squared timber and circular timber's measurements were separately conducted with 1,300 m/s as the standard ultrasonic velocity. The standard wood samples divided into two parts; a non-sound area (below the standard), and a sound area (above the standard). Furthermore, schematization of wood was compared with results naked eye observation. The drilling resistance test was performed for both length and thickness direction in wood. The internal of the drilling was set at 30 cm (length direction), 5 cm (width direction) and 30cm (thickness direction). A non-sound area was defined as that 1) amplitude is below 20% and 2) carbonization and deterioration are related.