• 펄프종이기술
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• 제36권5호
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• pp.62-68
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• 2004

The amount of non-lignin components in unbleached and oxygen-delignified kraft pulps and their impact on lignin determinations was investigated. The lignin analyses investigated were kappa number and Klason lignin in conjunction with acid-soluble lignin. The species investigated were loblolly pine, and aspen. The non-lignin components that impacted on lignin determination were residual extractives and hexenuronic acid in unbleached and oxygen-delignified kraft pulps. In the hardwoods, significant amounts of extractives remained after kraft pulping and oxygen delignification. These residual extractives in the hardwood pulps had an impact on the lignin determination, more so on the acid lignin method than kappa number. Hexenuronic acid only impacts on kappa number determination both softwood and hardwood pulps, not on acid lignin. Hexeneuronic acid contributed as lignin content more in aspen than pine pulps, and more in oxygen-delignified than unbleached kraft pulps. Impact of hexenuronic acid on should be corrected both softwood and hardwood pulps for accurate kappa number.

• 한국가구학회지
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• 제19권6호
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• pp.420-427
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• 2008

To study the suitability of chestnut as a cask for ripening traditional liquors, the absorption property for pure water, liquor with 30% alcohol content and ethanol with 95% alcohol content were investigated for five species. Oriental oak had the greatest amount of liquid absorption while chestnut had the smallest amount. The absorption amount linearly increased with increasing soaking time. The absorption amounts for each section were greatest in RT plane, and the difference between LR plane and LT plane was very small for all soaking conditions. The anisotropy of absorption amount for five species was greatest in Japanese cedar and was smallest in white mulberry on the whole. And the change of absorption amounts according to soaking conditions tended to decrease in softwoods and increase in hardwoods, and the difference among wood species was not clear. From this result, it was found that chestnut with a small absorption amount, regarding of soaking behavior, was a good material as a cask for ripening traditional liquors, whereas small diameter oriental oak with a great absorption amount was not suitable in this purpose.

• Journal of the Korean Wood Science and Technology
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• 제22권3호
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• pp.39-44
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• 1994

This study was carried out to investigate features pertaining to spiral thickenings, which was considered one of the most important diagnostic values, for wood identification. Species, kind of cells with spiral thickening, and ridge numbers of spiral thickening per axial mm were recorded in 71 families, 144 genera, 316 species of Korean hardwoods. Spiral thickening was observed in 128 of 316 species, about 40.5 % of all the investigated, and classified into 6 types on the basis of distributional patterns and morphological features as follows: 1. Type 1, present throughout all vessel element, which was found in 14 families, 19 genera, 43 species. 2. Type 2, present only in small vessel element, which was found in 18 families, 29 genera, 41 species. 3. Type 3, present both in small vessel element and wood fibers, which was found in 8 families, 17 genera, 29 species. 4. Type 4, present in wood fibers, which was found in 1 family, 1 genus, 1 species. 5. Type 5, present only in tail of vessel element, which was found in 4 families, 5 genera, 9 species. 6. Type 6, being present in vessel element faintly or partially, which was found in 2 families, 3 genera, 5 species.

• 펄프종이기술
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• 제42권2호
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• pp.61-66
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• 2010

Corn stalk, one of the most abundant agricultural residue in the world, was examined in this study to use it as an alternative fiber source of wood fiber. In order to find the proper way to utilize corn stalk more efficiently, the morphological properties and the papermaking properties of the, bast fibers and the corn pith, were evaluated respectively. Although the bast fiber fraction showed comparable properties to those for hardwoods in the fiber properties and the papermaking properties, the pith resulted in low brightness and low drainage rate. But the short and flexible fibers in pith fraction led to dense and compact handsheet structure, correspondingly the higher sheet strength. There big differences in properties between bast fiber and pith should be considered for the fully utilization of corn stalk.

• International Journal of Concrete Structures and Materials
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• 제9권1호
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• pp.61-67
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• 2015

The concept of horizontal shear connection utilization on wood-concrete beams intends to be an alternative connection detail for composite wood-concrete decks. The volume of sawn-wood is over three times more expensive than concrete, in Brazil. In order to be competitive in the Brazilian market we need a composite deck with the least amount of wood and a simple and inexpensive connection detail. This research project uses medium to high density tropical hardwoods managed from the Brazilian Amazon region and construction steel rods. The beams studied are composed of a bottom layer of staggered wood boards and a top layer of concrete. The wood members are laterally nailed together to form a wide beam, and horizontal rebar connectors are installed before the concrete layer is applied on top. Two sets of wood-concrete layered beams with horizontal rebar connectors (6 and 8) were tested in third-point loading flexural bending. The initial results reveal medium composite efficiency for the beams tested. An improvement on the previously conceived connection detail (set with six connectors) for the composite wood-concrete structural floor system was achieved by the set with eight connectors. The new layout of the horizontal rebar connectors added higher composite efficiency for the beams tested. Further analysis with advanced rigorous numerical Finite Element Modeling is suggested to optimize the connection parameters. Composite wood-concrete decks can attend a large demand for pedestrian bridges, as well as residential and commercial slabs in the Brazilian Amazon.

• 한국균학회지
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• 제40권4호
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• pp.292-295
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• 2012

구름버섯은 온대지역에서 흔히 발견되는 목재 부후균으로서 중요한 약용버섯의 일종이다. 본 연구에서는 커피박, 과립커피 및 과립 디카페인 커피의 구름버섯 균사체 생장에 미치는 영향을 조사하였다. 그 결과, 커피박은 10% 농도에서까지 그리고 과립커피의 경우 1% 미만에서 균사체 생육을 촉진시키는 것으로 확인되었다. 1% 커피박의 경우 무처리에 비해 10배 정도의 건조중량 증가가 측정됨으로써 구름균사체의 생육촉진제로서의 커피 효능을 확인할 수 있었다. 또한 커피는 균사체의 페놀화합물 및 항산화 효능 증대를 위한 유용 물질로 판단되었다.

• Journal of the Korean Wood Science and Technology
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• 제2권2호
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• pp.13-21
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• 1974

1. In the past, the smoke-pipe type dry kiln being characterized by the low cost of installation and easy operation was only used by the small scale of wood processing enterprisers for drying softwood and finishing air-dried stocks that were belonged to easy drying properties. The smoke-pipe type dry kiln usually was not suitable for drying hardwoods and green woods because of the difficulties of controlling drying conditions. 2. However, the smoke-pipe type dry kiln heated with smokeless coal which was designed and constructed by the authers was demonstrated to maintain higher accuracy of controlling temperature and humidity than the other smillar types of kiln. Also, since it was constructed with home made equipments, it is supposed to offer the opportunity to install the kiln by the small scale of wood processing enterprisers who could not install the dry kiln because of economical and technical difficulties. Thus, it is expected that promoting the spread of installing the dry kiln will realize the rational use of wood.

• 한국가구학회지
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• 제22권3호
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• pp.199-207
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• 2011

Examined the color of ten species of Korean broadleaf trees were experimented based on $L^*a^*b^*$ values and color difference (${\Delta}E^*ab$) between sapwood and heartwood, in order to analyze and determine the color, a critical visual and decorative factor of the broadleaf trees that can be used for making woodcraft and furniture. According to the result, the entire sapwood and heartwood, except the heartwood of Populus tomentiglandulosa, showed positive value in whiteness, redness, and yellowness and therefore contained yellow and red. None of the species showed color difference between sapwood and heartwood that was trace (0~0.5), slight (0.6~1.5), or very much; whereas Populus maximowiczii showed noticeable color difference (1.5~3.0); Salix koreensis, Betula platyphylla var japonica, Carpinus laxiflora, and Castanea crenata, appreciable and Populus tomentiglandulosa, Juglans mandshurica, Betula schmidtii, Alnus japonica, and Quercus variabilis, much. The color characteristics of heartwood and sapwood of the ten Korean broadleaf tree species studied in this research can be used as basic data for woodcraft or furniture production, especially when replacing foreign woods with Korean ones, and also contribute to convergence researches for science, engineering, and design fields.

• 한국인쇄학회지
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• 제28권2호
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• pp.1-11
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• 2010

The physicochemical characteristics, adhesion power, and conservation of imported tapes repairing documents that consisted of adhesive, carrier, and masking were investigated. Materials related to pressure sensitive adhesive produced in domestic companies were examined also. And then, the performance evaluation of prototype manufactured in our laboratory was undertaken. Both the pressure sensitive tapes were compared. The polyacrylate of adhesive agents such as polyacrylate, starch, Glue, and PVA of imported tapes was best. The adhesion strength, power, reversibility, and stability (deterioration) of imported tapes were analyzed. By comparing results of imported tapes, two adhesive agents were selected finally. The carriers of imported tapes are made of one of papers, cotton sheets, and felts. Major carrier material was a paper. The jutes, conifers, and hardwoods were main ingredient of papers. The durability of Hangi($18{\pm}2g/m^2$) was one and half times superior to imported one.

• 한국산림과학회지
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• 제88권3호
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• pp.374-378
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• 1999

본(本) 연구(硏究)는 매자나무과(科)의 매발톱나무와 당매자나무 그리고 대극과(科)의 예덕나무와 사람주나무에 있어서 목부(木部) 방사조직(放射組織)내 에 천공(穿孔)을 지니는 방사조직(放射組織) 구성세포(構成細胞)가 존재(存在)함을 처음으로 보고(報告)하는 것으로써 천공(穿孔)을 지니는 이들 방사조직(放射組織) 세포(細胞)의 천공(穿孔)은 도관요소(導管要素)에 발달(發達)하는 천공(穿孔)과 동일(同一)하게 단일천공(單一穿孔)을 지니는 것으로 밝혀졌다.