• Journal of Forest and Environmental Science
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• v.31 no.4
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• pp.267-271
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• 2015

The variations of wood density and mechanical properties of Juniperus polycarpos trees were studied in a natural forest in Iran. Sample disks were taken from each tree to examine wood density and mechanical properties (MOE and MOR) from pith to bark at breast height, 50%, and 75% of total tree height. The analysis of variance (ANOVA) indicated that radial position and height significantly affected all wood properties. The wood density, MOE and MOR were decreased along horizontal position from the pith to the bark and vertical direction from base upwards. Regression analysis showed that modulus of elasticity (MOE) and modulus of rupture (MOR) had a positive correlation with wood density.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.510-515
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• 2014

The anatomical and physical properties of tension wood (TW), opposite wood (OW) and lateral wood (LW) in the branches of Korean paulownia (Paulownia coreana) were compared. The diameter of TW vessels was larger than that of OW and LW vessels. The most distinctive feature of TW fibers was the presence of a gelatinous layer (G-fiber). The cell wall of TW fibers was nearly three times as thick as that of OW and LW. TW differed from OW and LW in density, X-ray diffraction pattern and shear and compressive strengths. The results obtained in this study showed clear differences in the anatomical and physical properties of TW, OW and LW of Paulownia coreana branch woods.

• Journal of the Korean Wood Science and Technology
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• v.29 no.3
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• pp.1-13
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• 2001

Compression, lateral, and opposite woods in the stem and branch of rimu (Dacrydium cupressinum Lamb.), a softwood species indigenous to New Zealand, were described and compared in the anatomical aspects. Qualitatively, growth rings were wide in the compression wood, intermediate in the lateral wood, and narrow in the opposite wood. Tracheid transition from early wood to late wood was very gradual in the compression wood but was more abrupt in both the lateral and opposite woods. When viewed transversely, compression wood tracheids showed a roundish outline except at the growth ring boundary but lateral and opposite wood tracheids were angular to rectangular in outline. Intercellular spaces were occasionally detected in the compression wood except in the late wood at the growth ring boundary but were absent from both the lateral and opposite woods. Slit-like extensions of the bordered pit openings caused by the location of pit apertures within short and narrow helical grooves were observed in the compression wood tracheids but not in the opposite or lateral wood tracheids. In the compression wood tracheids, fine striations in the form of fine checks or grooves were observed on the lumen surfaces and the innermost $S_3$ layer of secondary wall was absent. In the tracheids of lateral and opposite woods, the $S_3$ layer was sometimes absent but occasionally highly developed. Cross-field pits in the compression wood appeared to be piceoid due to slit-like pit apertures but those in the lateral and opposite wood tracheids showed cupressoid to taxodioid. Quantitatively, compression wood tracheids were somewhat shorter than those of opposite or lateral wood in stem but not different from the opposite or lateral wood tracheids in branch. The walls were thicker in the compression wood than in the lateral or opposite wood. Uniseriate rays in the compression wood were fewer than in the lateral or opposite wood.

• Journal of the Korean Wood Science and Technology
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• v.44 no.6
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• pp.890-896
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• 2016

Paulownia tomentosa is one of fast-growing wood species in Korea. In order to evaluate the solid bioenergy properties of Paulownia tree, this study examined the heating value, moisture content (MC), pH and proximate analysis of stem, branch, root, bark and leaf. The heating values of wood parts were slightly higher than those of bark and leaf, and that of branch was the highest among all the samples. The higher moisture content of bark and leaf referred to their lower heating value. Also, the pH of stem, branch and root was similar and lower than those of bark and leaf. The ash content of bark and leaf was much higher than that of wood parts, which is the one of the reasons for effect on the lower heating value and higher pH. While, the volatile matter content (VMC) of bark and leaf was lower than those of wood parts. The bark showed the highest fixed carbon content (FCC), while the FCC of stem was the lowest among all the samples. The obtained results are encouraging that the Paulownia tree could be totally utilized as alternative fuels for bioenergy production.

• Journal of Korean Society of Forest Science
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• v.80 no.3
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• pp.296-302
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• 1991

Compression wood and opposite wood formed in a branch of Taxodium distichum Rich. is described and compared in qualitative and quantitative anatomical aspects. The qualitative features of compression wood appeared to differ from those of opposite wood in very gradual tracheid transition from earlywood to latewood, roundish tracheid shape on cross surface, tracheid tip distortion on radial surface, and existence of intercellular spaces and helical cavities. In quantitative features, compression wood tracheids showed shorter lengths than opposite wood. The ray density and the number of uniseriate rays were greater in compression wood than in opposite wood but the height of uniseriate rays in compression wood was smaller than in opposite wood.

• Journal of the Korean Wood Science and Technology
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• v.33 no.1 s.129
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• pp.38-47
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• 2005

Compression, lateral, and opposite woods in a branch of Pinus parviflora S. et Z. were described and compared in the qualitative anatomical aspects through light and scanning electron microscopy. Tracheid transition from earlywood to latewood in the compression wood appeared to be relatively more gradual than in the opposite or lateral wood. Growth ring width and proportion of latewood were thought to be greater in the compression wood than in the lateral or opposite wood. The latewood tracheids of compression wood in transverse surface were mostly round, differently from those of lateral and opposite woods with square to angular shapes. Also, intercellular spaces, helical cavities and checks, and slit-like pit apertures were observed only in the compression wood tracheids. Cross-field pitting in the compression wood appeared not to be used as diagnostic guide because of their severe alteration from normal fenestriform or window-like type to cupressoid to taxodioid types. In tangential surface, fusiform rays in the compression wood were wider but lower than those in the lateral wood or opposite wood. In conclusion, compression wood was different from lateral and opposite woods but lateral and opposite woods were almost identical in qualitative anatomical features.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.11a
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• pp.21-33
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• 2007

CPAM has been applied to the paper industry for the purpose of wet-end improvement for a long time. And molecular weight and charge density have been managed most important quality factors to make CPAM for this application. Recently branched CPAM was developed to improve retention and drainage characteristics and we considered branch degree of CPAM as important factor as molecular weight and charge density. In this experiment, we tried to investigate physical and chemical properties to determine branch degree and flocculation efficiency using Arbocell pulp which was recently developed micro size pulp and finally we applied retention and drainage test under the ONP stock condition.

• Journal of the Korean Wood Science and Technology
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• v.13 no.1
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• pp.3-18
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• 1985

In Korea, a study on the anatomical features of pitch pine (pinus rigida Miller) branch wood through photo-microscopical method was reported in 1972 by Lee. Therefore, as a further study of Lee's on the anatomical features in branch wood of pinus rigida miller that grows in Korea, compression wood, opposite wood, and side wood were selected and treated for the purpose of comparing their structures revealed on cross and radial surface through scanning electron microscope in this study. The obtained results in this study were summarized as follows; 1. The trachied transition from earlywood to late wood is very gradual and the tracheids are nearly regular in both arrangement and size in compression wood but this transition in opposite wood and side wood is abrupt and the tracheids in opposite wood and side wood are less regular than those in compression wood. Also, the annual ring width of opposite wood is narrower than that of compression wood or side wood and the rays revealed on cross surface of side wood are more distinct than compression wood and opposite wood rays. 2. The tracheids of compression wood show roundish trends especially in earlywood but those of opposite wood and side wood show some angular trends. And intercellular space, helical cavity, and spiral check are present in both earlywood and latewood of compression wood but not present in opposite wood and side wood irrespective of earlywood and latewood. 3. The wall thickness of latewood tracheid is similar to that of earlywood tracheid in compression wood whereas the wall thickness of latewood tracheid is by far thicker than that of earlywood tracheid in opposite wood and side wood and the S3 layer of secondary wall is lack in compression wood tracheid unlike opposite wood and side wood tracheid. 4. The tracheids in compression wood are often distorted at their tips unlike those in opposite wood and side wood and the bordered pit in compression wood tracheid is located at the bottom of helical groove unlike that in opposite wood and side wood tracheid. 5. The bordered pits in radial wall of opposite wood and side wood tracheids are oval in shape but those of compression wood tracheids show some modified oval shape. 6. In earlywood of side wood, the small apertures of cross-field pits are roundish triangle to rectangle and the large one are fenestriform through the coalition of two small ones. However, the small apertures of cross-field pits are upright oval and the large ones are procumbent oval shape in earlywood of opposite wood and the apertures of cross-field pits in compression wood are tilted bifacial convex lens shape in earlywood and slit in late wood because of the border on tracheid side.

• Journal of the Korean Wood Science and Technology
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• v.49 no.3
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• pp.254-266
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• 2021

Using forest resources involves solving complex and diverse tasks. At the same time, one of the key goals in the field is improving the quality of forest infrastructure. This direction requires adequate mathematical and economic justification. Moreover, creating an effective infrastructure will not only increase the accessibility and usage volumes of wood and other forest resources, but also contribute to the development of continuous and sustainable forest management. The existing practice of making decisions in terms of the organizational and technological aspects of logging, based on the personal experiences of managers or leading specialists in enterprises, hinders the achievement of constant optimal efficiency. The paper presents results that are a continuation of the research cycle of the authors' team in the fields of optimization and algorithmization of various logging processes. The focus of the study lies in the processing and movement of wood resources, the most valuable products of the investigated groups of enterprises. To this end, the paper presents a developed algorithm for determining an effective technological chain of transportation in logging operations, and for improving loading and unloading processing operations under dynamic natural and production conditions. This algorithm serves as the methodological basis for designing logging infrastructure in a dynamically changing environment.

• Journal of the Korean Wood Science and Technology
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• v.50 no.5
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• pp.338-352
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• 2022

Herein, water and ethanol extracts were obtained from the leaves, branches, kernels, and pericarp of Quercus gilva and subsequently analyzed for antioxidant activity and circadian rhythm regulation effects. Candidate components that may affect circadian rhythm and antioxidant activity were investigated to discover potential functional materials. Antioxidant activity was analyzed via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity assays, showing that the hot water extract exhibited higher activity than that of the ethanol extract. In particular, the branch extract showed high antioxidant activity. By measuring total contents of polyphenols, flavonoids, and tannins, the hot water branch extract showed the highest concentrations, highlighting their significant contribution to the antioxidant activity. Examination of the circadian rhythm regulation of each extract showed that the ethanol extract exhibited greater impacts on the circadian rhythm amplitude compared to the water extract. The branch ethanol extract induced circadian rhythm amplitude changes via clock gene Bmal1 expression regulation. Determination of 12 phenolic compound concentrations showed that the branch ethanol extract contained many phenolic compounds, including catechin. This suggests that these com- pounds affected circadian rhythm regulation. In conclusion, the hot water branch extract has potential as an natural antioxidant material, while the corresponding ethanol extract has potential as a functional material for regulating circadian rhythm.