• Journal of Forest and Environmental Science
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• v.33 no.3
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• pp.233-238
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• 2017

This study was carried out to figure out the number of logs for sawtimber by DBH and height class and to compare merchantable volume ratio by categorizing into sawtimber, lagging board and pulpwood, and others for Pinus densiflora, Pinus koraiensis, and Larix kaempferi. Logs for sawtimber were hardly produced in small DBH class of three species, but produced evidently from medium DBH class. In large DBH class, the number of logs for sawtimber were noticeably different among species: 4.3 logs for L. kaempferi, 2.6 logs for P. densiflora, and 1.0 logs for P. koraiensis on average. Similarly, merchantable volume ratio for sawtimber were largely different among species in large DBH class with higher than 15 m: 82% logs for L. kaempferi, 60% logs for P. densiflora, and 44% logs for P. koraiensis. When compared to the upper diameter and upper height by species with regard to the last log of a tree produced for sawtimber, upper diameter was smallest with 14.1 cm and upper height was highest with 12.2 m in L. kaempferi. Overall, L. kaempferi was considered as the more commercial species for sawtimber production than P. densiflora and P. koraiensis.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.362-368
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• 2007

This study was conducted to estimate merchantable volume and yield per diameter (DBH) class of Pinus koraiensis and Larix kaempferi. Stem volume of trees in each diameter class was calculated using the existing equations for taper and height curve. Saw logs and pulpwood volume were then estimated from the stem volume in each diameter class. The final step was to estimate merchantable volume and yield from saw logs, assuming saw logs were used for lumber (boards or dimension products) production only. The results showed that the stem volume of Larix kaempferi was 23~38% higher than that of Pinus koraiensis at the same diameter classes. Both species were able to produce saw logs from the diameter class of 18 cm. Saw logs and pulpwood yield for both species rapidly increased due to the size limitation on small end diameter. This yield reached a maximum of 90% and 88% at 26 cm and 38cm diameter class, respectively, for Pinus koraiensis and Larix kaempferi. Lumber yield estimated for board products ranged from 23% to 56%. In the case of dimension products, Lumber yield became significantly smaller as saw logs were used for larger dimension products. These results can be used for calculating merchantable volume and economic value of trees, as well as determining final lumber products.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2003.11a
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• pp.17-26
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• 2003

Nalita wood(Trema orientalis) is one of the fastest growing woods in the world. It may be a viable species for pulpwood. The physical, chemical and morphological properties of Nalita were studied. The total lignin, pentosan and holocellulose content in Nalita wood were 24.7%, 22% and 81.2%, respectively. Its fiber length was about 0.92 mm, which are comparable to Acacia mangium. Nitrobenzene oxidation of Nalita wood meal indicated that the guaciayl and syringyl unit were the major constituent of Nalita lignin. Nalita produced 50% pulp yield at Kappa number 21 in soda-anthraquinone process. The strength properties of Nalita pulp were comparable to other tropical hardwood pulp. At $40_{\circ}$ SR, the breaking length, burst index, tear index and total energy absorption were 6000 m, $3.5kPa{\cdot}m^2/g\;and\;7.0mN{\cdot}m^2/g\;and\;75J/m^2$, respectively.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.3
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• pp.56-62
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• 2012

Recycled pulp therefore play a very important role in the paper industry today as a substitute for virgin pulp. In many countries of the world, the paper industry could not exist as it does without recycled pulp. Because, this is mainly due to economic reasons. Particularly in our country, the additional reason is the scarcity of native pulpwood resources. Therefore, the use of recycled pulp is very important. This study was aimed to apply recycled pulp to textbook paper. So we made a paper containing 30% recycled pulp and investigated about print quality, such as color reproduction, trapping, contrast, dot gain, gloss and print through. The results showed that is similar to existing textbook papers.

• KSBB Journal
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• v.32 no.1
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• pp.1-8
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• 2017

Bamboo is a plant belonging to the Gramineae family, and can be used as valuable bioresources for many industrial applications. Bamboo has some useful properties and having a lot of beneficial uses such as a bamboo ware, agriculture material, building construction material, pulpwood, etc. Bamboo stem has a large amount of active ingredients that those of bamboo leaves. The stem of bamboo can be processed into various biomaterials including cellulose and lignin, and sometimes uses as foods, cosmetics and medicines using stem extracts with polyphenol compounds. For cosmetic applications of bamboo stems, especially, the constituents of bamboo stem are suitable for inner beauty (cosmetic food) products showing antioxidant and UV-protecting activities. This review summaries the recent literature data and discusses the versatile uses of bamboo stem and its extracts mainly for cosmetic application.

• Journal of the Korean Wood Science and Technology
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• v.49 no.2
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• pp.191-209
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• 2021

Australia has significant wood resources in its native forest, but the resource available for harvest becomes lesser due to the conversion of native forest to conservation reserves. The natural occurrences of bushfires, droughts, and cyclones are highly destructive, making the situation worse. The shortage of wood resources is having a significant negative impact on Australia because wood is so scarce that they cannot meet domestic demands, especially durable wood. Australia cleared approximately 100 million hectares of its land to establish forest plantations, and two million trees were planted. However, most of these plantations are for pulpwood production; however, their application for high-value products is limited due to their undesirable properties. Wood modification is a process of improving unfavorable wood properties to be utilized for a wide range of applications. Australia has not adopted any of these modification processes; it still depends on the less toxic wood preservative to treat wood. This study focuses on the recent advancement in industrial wood modification worldwide and how it may be used to modify Eucalyptus wood for high-value applications. The opportunities and suggestions for Eucalyptus wood modification in Australia will be discussed. Before the study concludes, the future of commercial wood modification for Eucalyptus plantation in Australia will also be presented.

• 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.19 no.2
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• pp.56-64
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• 1991

The destructed chips(Pinus rigida Mill) were sulfonated under different conditions and defiberated. The yields and strengths of pulp, fatty acid and resin acid in sulfonated chips were determined. The results of this work were as follows: 1) A sulfonation caused a yield reduction to 97.9~88.2% at single stage. and to 94.9~88.2% at two stage pretreatment. The pulp yields were rapidly draped with increasing cooking temperature from $130^{\circ}C$ to $150^{\circ}C$ 2) Pulp strengths were improved with iacreasing cooking temperature. A sulfonation with 5% $Na_2SO_3$/NaOH(8/2) at single stage and 2% NaOH-5% $Na_2SO_3$ at two stage were most effective and gave the best combination of strength properteis. 3) Fatty acid esters in chips were mostly consisted of palmitic and olleic acid. During a sulfonation the former increased extensively, and the latter was lost with increase of cooking times. The amount of pimaric type in the chips was relatively decreased by the pretreatnent and abietic-type increased. But the changes between two resin acid types were insignificant. 4) The effciency of pitch removal was dependant upon cooking liquor pH. To remove sufficiently the resinous substance, the chips must be sulfonated at over pH 12. Therefore, taking account of pitch removel, two stage sulfonation is considered suitable as reinforcement pulp for newsprint manufacture from pitch pine chips : 2% NaOH($60^{\circ}C$ 1 hr) at first stage and 5% $Na_2SO_3$ ($130^{\circ}C$, 1hr) at secund stage.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.305-309
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• 2006

This paper presents and illustrates the application of a growth and yield model that supports both forest and mill side volume and value estimates. Traditional forest stand growth and yield models represent the forest landowner view of yield and economics. Predicted yields are estimates of what one would expect from a procurement cruise, and current stumpage prices are applied to investigate optimum management strategies. Optimum management regimes and rotation ages obtained from the forest side view are unlikely to be economically optimal when viewed from the mill side. The actual distribution of recoverable manufactured product and its value are highly dependent on mill technologies and configurations. Overcoming this limitation of growth and yield computer models necessitates the ability to predict and price the expected manufactured distribution of lumber, lineal meters of veneer, and tonnes of air dried pulp fiber yield. With these embedded models, users of the yield simulator can evaluate the economics of possible/feasible management regimes from both the forest and mill business sides. The simulator is a forest side model that has been modified to produce estimates of manufactured product yields by embedding models for 1) pulpwood chip size class distribution and pulp yield for any kappa number (Schultz and Matney, 2002), 2) a lumber yield and pricing model based on the Best Opening Face model developed by the USDA Forest Service Forest Products Laboratory (Lewis, 1985a and Lewis, 1985b), and 3) a lineal meter veneer model derived from peeler block tests. While the model is strictly applicable to planted loblolly pine (Pinus taeda L.) on cutover site-prepared land in the United States (US) Gulf South, the model and computer program are adaptable to any region and forest type.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.56-68
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• 1985

This study was conducted (1) to measure the nitrogen content of various parts of trees in a 24-year-old Pinus koraiensis plantation, providing a harvest method with the least impact on the self-serving mechanisms in the nitrogen status of the ecosystem and (2) to examine the seasonal changes in inorganic nitrogen (ammonium salt and nitrate, separately) at various soil depths and to study the self-serving mechanisms for nitrogen at the ecosystem, providing an appropriate method and season for the application of nitrogen fertilizers. The results obtained in this study were as follows; 1) Of the total nitrogen content of the total tree biomass (except for roots), nearly 61.5% was distributed in the needles, 20% in the branches, 5.5% in the stem bark, and 13% in the stem wood. Therefore, the harvest method of removing only wood parts for pulpwood production has little impact on the self-serving mechanisms of the site's nitrogen status. 2) Inorganic nitrogen concentrations decreased with increasing soil depths. The seasonal average concentration of inorganic nitrogen was highest in early spring and decreased in the following descending order; autumn, tollowed by mid-summer, and early summer. This pattern resulted from the fact that the loss of nitrate was greatly influenced by environmental factors. Thus, it was suggested that an application of active nitrogen fertilizer would be appropriate in spring.