• 보존과학연구
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• s.11
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• pp.87-105
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• 1990

Chemical and micro morphological changes of archaeological waterlogged woods from shipwrecked materials in marine situations were investigated which were submerged in seabed for over 900 years. Tested Wood species were Pinusdensiflora, Zelkova serrata, Quercus acutissima and Camellia japonica. The obtained results were summarized as follows; Chemical analysis showed that lignin content was increased, whereas the amout of holocellulose was heavily decreased in the degraded archaeological lwoods(DAW), when compared to the recent woods. The amount of alkalineextractives in the DAW was extremley high. IR spectra showed that disappearance of absortion band at $1,730㎝^-1$ intensity increase at 1,600, 1,500 and $1,270㎝^-1$ and the emergence of single band around $1,050㎝^-1$.Microscopic investigation showed that cell wall of latewood tracheids and fiber in the DAW were severely degraded while, early wood tracheids less degraded. Degradation in the cell wall was mainley occurred in $S_2$layer, while the middle lamella was the least degraded. The micro morphological characteristics of DAW were separation of secondary wall from middle lamella, cavities aligned with micro fibril angle in $S_2$layer and granular appearance of secondary wall by the bacterial attack.

• Journal of the Korean Wood Science and Technology
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• v.50 no.6
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• pp.436-447
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• 2022

Lignocellulose nanofibrils (LCNFs) were prepared using a two-step deep eutectic solvent (DES) and enzymatic pretreatment followed by mechanical defibrillation, and we examined the effects of enzymatic pretreatment conditions on different characteristics of the LCNFs thus obtained. The LCNFs yielded using the two-step DES pretreatment (Enz-LCNF) exhibited a well-defibrillated entangled web-like structure with an average fiber diameter ranging from 15.7 to 20.4 nm. Furthermore, we found that the average diameter and filtration time of the Enz-LCNFs decreased with an increase in enzyme concentration and enzymatic treatment time, whereas we detected a concomitant reduction in the tensile strength of the Enz-LCNF sheets. The Enz-LCNFs were characterized by a typical cellulose I structure, thereby indicating that the enzymatic treatment causes very little damage to the crystalline form.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.15-22
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• 2015

The crop production technologies keep in improving and the cultivation becomes more standardization owing to the significant developments of various agricultural materials. The artificial soil and base system for root could be one of the major technologies for the modern cultivation especially for controlled horticulture. Although the perlite, cocopeat, and peat moss are the major components of the artificial soil and are broadly used for various application, there is a great need for the new alternative materials for overcoming the low nutrition and the possible shortage of raw materials. In this study, the application of oil palm EFB fiber as an alternative materials for artificial soil especially for the seeding pad components was evaluated. The changes in the structural properties and the functional properties such as moisture holding properties were compared by laboratory produced seeding pads with different mixture of oil palm EFB fiber. The addition of fibrillated EFB fiber resulted in the significant increase in durability of the seeding pad, which showed the possible application of EFB fiber to the seeding pad instead of the wood fiber (UBKP). The moisture holding properties and the germination condition characteristics of the EFB fiber showed the slight less than those of the cocopeat, which require more sophisticated study for improving the functional properties of seeding pad made of the EFB fiber.

• Journal of the Korea Furniture Society
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• v.10 no.2
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• pp.17-27
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• 1999

As a countermeasure to reach self-sufficiency for wood supply and demand, we have to develop wood substitutes. Rice hull is the cheapest fiber material we can get in Korea, What is better the yield of rice hull amounts to 1 million tons per year. Before carrying out this study, new ecomaterial rice hull board for housing materials was developed successfully. In order to evaluate whether the rice hull board with or without bioceramic treatment is suitable for housing materials, we studied the environmental effect of the above materials in comparison with the polycarbonate, stainless, or concrete on the adaptation (body weight, water/feed consumption, general signs, urinalysis, autopsy, etc) and the reproduction(litter size, newborn adaptation, etc)of mice. In conclusion, the concrete cage was the worst in the adaptation and so was the stainless steel cage in the reproduction. The rice hull board cage with or without bioceramic treatment was superior or equivalent to other material cages from the standpoints of the adaptation and reproduction.

• Journal of Forest and Environmental Science
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• v.27 no.3
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• pp.183-194
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• 2011

This study reviewed on the research trend of sources and utilization of the byproducts(Lignin) from bioethanol production process with lignocellulosic biomass such as wood, agri-processing by-products(corn fiber, sugarcane bagasse etc.) and energy crops(switch grass, poplar, Miscanthus etc.). During biochemical conversion process, only Cellulose and hemicellulosic fractions are converted into fermentable sugar, but lignin which represents the third largest fraction of lignocellulosic biomass is not convertible into fermentable sugars. It is therefore extremely important to recover and convert biomass-derived Lignin into high-value products to maintain economic competitiveness of cellulosic ethanol processes. It was introduced that lignin types and characteristics were different from various isolation methods and biomass sources. Also utilization and potentiality for market of those were discussed.

• Polymer(Korea)
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• v.37 no.5
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• pp.613-617
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• 2013

The effects of nano size kenaf cellulose fiber on mechanical property of polypropylene (PP) composite were investigated. The addition of nano-kenaf in place of natural kenaf showed higher tensile strength, flexural strength, impact strength, and heat deflection temperature compared to the natural kenaf filled PP composite, while it shows lower melt flow index, elongation%, and flexural modulus. These seemed to be due to the increased surface area of nano-kenaf fiber contacting PP matrix and reduced impurities such as volatile extractives on the fiber surface.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.4
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• pp.68-74
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• 2003

Kenaf(Hibiscus cannabinus L.) cultivar, Tainung 2, had been grown for 152 days at the experimental farm of Jinju National University, Gajoa-dong, Jinju-si, Kyongnam, Korea. The planting, growth rate, fertilization and structural characteristics as well as the cultivation and growth characteristics of kenaf, and the product usage were investigated. The narrowest diameter at kenaf bottom was 10 mm, the widest 42 mm and the average about 28 mm, and the shortest height 150 cm, the tallest 480 cm and the average about 350 cm. The weight of a core fraction was 68.1％ and a bast fraction 31.9％. The weight ratio of core material to bast fiber was 2.31. The weight ratio of dry stem was 73.5％ and that of leaves 26.5％. The weight of dry plant produced in 1 $m^2$ was 1,467 g, and about 1,052 g of stem could be used for the commercial purpose, The application of fertilizers resulted in the increase of the growth rate of the diameter at plant bottom and the height. Bast fiber, phloem ray and cortex parenchyma cell were observed in bast, and vessel, wood fiber and ray in core.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.1
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• pp.47-56
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• 2011

This study was carried out to investigate the characteristics of the Hanji which had been used for movable types printing volumes of the Joseon Dynasty. A total 29 volumes which had printed with metal and wooden movable types, were examined on the physical properties, fiber morphology, and color reactions. The grammage of all of the Hanji which had been used for movable types printing volumes were $13.10-51.65g/m^2$ and on the average was $25g/m^2$. The apparent density of the Hanji was $0.23-1.65g/cm^3$ and on the average was $0.4g/cm^3$. In almost all movable types printing volumes, the Hanji had undergone Dochim which is a processing of printability improvement. Through the examination on fiber morphology and color reactions, Hanji was investigated into that all of those were made from paper mulberry bast fiber.

• Journal of the Korean Wood Science and Technology
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• v.39 no.6
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• pp.538-547
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• 2011

In this study, eco-friendly hybrid composite boards were manufactured from green tea and wood fibers for application as interior materials with various functionalities of green tea and strong strength properties of wood fibers. In this relation, the effect of green tea content on dynamic MOEs (modulus of elasticity) of these green tea and wood fibers composite boards were investigated. The dynamic MOEs of hybrid composite boards were lower than those of control boards without green tea, and the values decreased with the increase of green tea content. Also, the dynamic MOEs appeared to be somewhat different by resin type used for board manufacture. The hybrid composite boards manufactured from $E_1$ grade urea resin, which has higher molar ratio of formaldehyde to urea than that of $E_0$ grade one, were 1.06~1.54 times higher than that manufactured from $E_0$ grade. And, the differences between hybrid composite boards manufactured from both adhesive increased with the increase of green tea content. On the other hand, high correlations were found between dynamic MOE and static bending strength performances, it was concluded that static bending strength performances could be estimated from the dynamic MOE, except for a few hybrid board types with large variations.

• Journal of Korean Society of Forest Science
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• v.45 no.1
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• pp.62-67
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• 1979

Ultraviolet microscopy of ultrathin sections of wood has proved to be one of the useful means for determining the lignin distribution in the various regions of the cell wall. Also, spectral approach and quantitative analysis of isolated compound middle lamella fraction from birch xylem have revealed that the lignin associated with the vessel secondary wall and middle lamella is composed predominantly of gualacylpropane units. Lignin deposited in the fiber and ray parenchyma secondary walls is composed mostly of syringylpropane units. The middle lamella lignin around fibers and ray cells contains both guaiacyl and syringyl propane quits. On the basis of the results above, this research was carried out to clarify the origin of milled wood lignin (MWL) by analysing the chemical characteristics of ML MWLs extracted at various milling stages. The amount of phenolic hydroxyl-, ${\alpha}$-carbonyl-, and methoxyl-group in the MWL's increases the milling time. And progressive mining contributes to the merease of ratio of syringylaldehyde to vanillin(S/V ratio) after nitrobenzene oxidation of MWL. Accordingly, It could be concluded that milled wood lignin extracted at the initial milling stage derives from compound middle lamella region of cell wall, whereas, with progressive milling, lignin of secondary wall of fiber is introduced gradually to milled wood lignin. These results are suggesting that heterogeneous chemical structure of lignins in hardwood exists. Although milled wood lignin at the initial stage seems to have lower molecular weight in comparison with milled wood lignin extracted at final milling stage from the result of Gel-filtration curves, further study would be required on molecular weight distribution of milled wood lignin in future.