• 펄프종이기술
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• 제30권2호
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• pp.74-84
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• 1998

This study was carried out to investigate the papermaking characteristics of paper mulberry(Broussonetia kazinoki) for new Korean traditional paper(Hanji). Hanji has been traditionally made only with the bast fiber of paper mulberry. Besides mulberry bast part, wood core was utilized separately or in mixed forms as raw materials for the new Hanji. Hanjis made from the solfomethylated pulp were shown higher brightness and sheet strengths than those from alkali and alkali-hydrogen peroxide pulps. The brightness of solfomethylated pulp was found to be high enough not to need additional bleaching. In the physical properties of the Hanjis mixed with bast part and wood core pulps, the handsheet strengths were decreased as the increase of the wood core pulp contents. But the sheet strengths of Hanjis containing 10∼30% of wood core pulps were higher than those of the Hanji containing bast part pulp only. The sheet formations were improved as the increase of wood core pulp contents, while the sheet strengths were decreased.

• Journal of the Korean Wood Science and Technology
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• 제9권3호
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• pp.24-30
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• 1981

This experiment was carried out to determine the drying time from green to oven dry and estimate the moisture content of wood, such as red lauan (Shorea Spp.), Douglas fir (Pseudotsuga menziesii), Birch (Betula platyphylla), and oak (Quercus aliena), at various thickness, paralleled to fiber, of specimen for M.C. by oven dry method (100-105$^{\circ}C$). The results obtained are summarized as follows: 1. The drying time from green to oven dry decreases as the thickness of specimen for M.C. becomes to be thined, and that time at 10mm thickness are 14 hrs, for birch wood and 24 hrs, for oak wood. 2. The relative formulae between thickness (X) of specimen for M.C. and drying lime (Y) from 12% to oven dry are showed in Fig. 3. 3. The M.C. based on the weight of specimen for M.C. at t% can be obtained from the formula (2), and the drying time to 1% are shorter than that time to oven dry by approximately three times.

• Journal of the Korean Wood Science and Technology
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• 제20권1호
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• pp.51-59
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• 1992

The acetylation of papermaking pulp fiber(SwBKP, SwUKP, HwBKP and HwBCTMF) is carried out to modify the characteristics of pulp and paper. The effects of the addition of acetylated pulp on the filler retention and paper properties were investigated. The acetylation depended upon pulp type and the content of short fiber and fines. The addition of acetylated SwBKP did not deteriorate the retention of clay, talc and calcium carbonate, while the retention of titanium dioxide was increased with the addition of 20% and above. The brightness opacity, air permeability and tear strength were improved, but water resistance, burst strength and folding endurance were decreased by the addition of acetylated SwBKP and SwUKP. The tensile strength of SwBKP was increased until 20% of acetylated pulp is added, and then decreased. The tensile strength of SwUKP, however, was not changed until the acetylated pulp of 25% is added. The dimensional stability was improved by the addition of acetylated pulp and showed the different response to SwBKP and SwUKP.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.265-270
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• 2006

This paper reports an improved headspace gas chromatographic method for the determination of carboxyl group content in wood fibers. Pretreatment of wood fibers was applied using dilute HCl to convert carboxyl groups to carboxylic acid groups and then using deionized water to wash fiber samples thoroughly. The samples were finally air dried. Sodium bicarbonate solution was used to react with carboxylic acid groups of the pretreated fibers in a closed testing vial to release carbon dioxide. The content of carboxyl groups in fibers was accurately quantified by determining the amount of carbon dioxide released by a headspace gas chromatograph equipped with a thermal conductivity detector. The modified process for fiber sample pretreatment increased the reliability and accuracy in measuring carboxylic acid groups. The present method is simple, accurate.

• Journal of the Korean Wood Science and Technology
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• 제44권1호
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• pp.67-74
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• 2016

유리섬유 보강집성재의 볼트접합부 항복전단내력을 예측하기 위해 인장형 전단시험을 통해 측정된 실측값과 설계기준에 의한 예측값을 비교하였다. 볼트접합부의 항복전단내력 예측식을 위해 층재의 방향별 탄성계수, 포아송비, 전단계수를 측정하였다. 설계기준의 예측식 보정을 위해 유리섬유 보강집성재의 파괴거동을 반영한 파괴인성계수($K_{ft}$)를 적용하여 보정항복전단내력을 비교하였다. 층재의 탄성계수는 섬유방향에 따라 연륜폭, 연륜각과 높은 상관관계를 보였다. 유리섬유 보강집성재의 보정항복전단내력은 직경과 보강재에 따라 실측치와 비슷한 경향을 보였으며, 직물형 유리섬유보강집성재의 볼트접합부가 가장 높은 내력성능을 보였다. 볼트직경과 보강재에 따른 유리섬유 보강집성재 볼트접합부의 항복전단내력은 건축구조설계기준의 제안식을 보정한 예측치가 가장 잘 일치하였다.

• Journal of the Korean Wood Science and Technology
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• 제51권4호
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• pp.309-319
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• 2023

Bamboo culm is in the form of a tube/pipe, composed of internodes which are bounded by a partition/diaphragm (node). Anatomically, bamboo is composed of vascular bundles and parenchyma ground tissue. One of the constituents of vascular bundles is fibers that are grouped to form a fiber sheath. The anatomical structure of the nodes and internodes is thought to influence the strength of bamboo strips, including tensile strength. This study aimed to determine the characteristics of vascular bundles (distribution and fiber percentage) and their effects on the density and tensile strength of Gigantochloa apus bamboo strips with and without nodes. The bamboo culms were divided into three parts (outer, middle, and inner) along the radial direction. The results showed that the distribution of vascular bundles and percentage of fiber sheaths decreased significantly from the outer to the inner layer. This also had a significantly decreased density and tensile strength. Furthermore, the number of vascular bundles (in the transverse plane) was greater in the internodes than in the nodes. Anatomically, the orientation of the vascular bundles at irregular nodes is observed in the radial and tangential planes, where the direction is not only in the axial direction, but also in the radial and tangential directions. This caused the tensile strength of the G. apus bamboo strips to be lower at the nodes than at the internodes.

• Journal of the Korean Wood Science and Technology
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• 제48권6호
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• pp.878-887
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• 2020

A neutral extract (NE), that is soluble in cold water and has excellent antioxidant activity, from Pinus radiata pine bark was prepared by sodium bicarbonate treatment, and its chemical characteristics were investigated. NE was prepared by treating P. radiata bark with 0.8% NaHCO₃ aqueous solution with a 5 : 1 liquor-to-bark ratio at boiling temperature for 1 h, resulting in 44% yield and final pH of 6.66. The yield of NE was 11% higher than that of the hot water extract (HWE) due to the increase in the solubility of polyphenols, the main component in the bark, by NaHCO₃ treatment. NE was characterized through FT-IR, NMR, and MALDI TOF MS analyses. The results indicated that NE is mostly composed of proanthocyanidins (PAs) consisting of procyanidin (PC) units. The acetylated neutral extract (Ac-NE) had weight average molecular weight (${\bar{M}}w$) of 5,300 Da. The Ac-NE had wide molecular weight distribution and its polydispersity (${\bar{M}}w/{\bar{M}}n$) was 6 times higher than that of pure PA. The antioxidant activity of NE was determined by 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and showed that NE had comparable antioxidant activity with pure PA.

• Journal of the Korean Wood Science and Technology
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• 제49권2호
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• pp.134-141
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• 2021

This study was conducted to investigate the potential of the neutral extract (NE) prepared by treating P. radiata bark with aqueous NaHCO3 solution as a natural dyestuff. Silk and cotton fabrics were dyed at four different NE concentrations, 0.5%, 1.0%, 1.5%, and 2.0% o.w.b. (on the weight of bath). The fabric to liquid ratio of 1 : 50, dyeing temperature of 90℃, and dyeing time of 90 min were used as the fixed condition. The appropriate NE dyeing concentration of silk and cotton fabrics was 1.5% o.w.b. Colors of the dyed silk and cotton fabrics were brown and light brown, respectively. From colorfastness assessment, both dyed silk and cotton showed good washing and rubbing fastness, but poor light fastness. NE dyed fabrics exhibited excellent ammonia deodorization property and antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae. Therefore, NE of P. radiata bark could have the potential for use as a functional brown dyestuff.

• 펄프종이기술
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• 제40권4호
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• pp.1-9
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• 2008

The utilization of non-woody fibers with the fast growing annual plants has occurred in the paper industry to replace wood and preserve environment of the earth. The non-woody fibers generally used for papermaking are paper mulberry, gampi, manila hemp, rice straw, bamboo, and coton linter etc.. Recently Kenaf has been spot-lighted for the same application. Kenaf is an annual plant of Hibiscus species of Malvaceae family. Kenaf, a rapid growing and high harvesting non-woody fiber plant, was identified as one of the promising fiber sources for the production of paper pulp. This study was carried out to investigate the pulping characteristics of Kenaf bast fiber for Hanji (traditional Korean paper) manufacturing by different pulping methods, such as alkali, alkali-peroxide and sulfomethylated pulpings. It was possible to make superior grade of Hanji. Especially sulfomethylated pulping was resulted in superior pulp in terms of higher yields and qualities in comparison to those of the other pulping methods. Hanji from sulfomethylated pulp was shown the highest brightness of over 60% and higher sheet strength. In addition, the morphological features of pulp fibers (pulp compositions) affect to the sheet properties. Therefore the effect of fiber distribution index(FDI) which was calculated from the data of Confocal laser scanning microscopy(CLSM) on the sheet properties of Kenaf Hanji was also discussed.

• Journal of Nutrition and Health
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• 제36권1호
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• pp.9-17
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• 2003

본 연구에서는 참나무(oak wood)류중 신갈나무(Querrus mongolica)로부터 수용성 식이섬유소의 제조와 제조된 수용성 식이섬유소의 생리적 기능성을 검정하고자 하였다. 신갈나무로부터 수용성 식이섬유소의 분리는 전처리 기술로써 폭쇄처리를 하였으며 최적 폭쇄전처리 조건은 25kgf/$\textrm{cm}^2$의 압력으로 6분간 처리하였다. 폭쇄시료를 탈리그닌 처리하기 위해 가장 효과적인 방법중 1% NaOH 용액으로 수회여과 처리 하였다. 앞에서 탈리그닌된 시료를 효소가수분해 처리하기 위 해 사용된 효소로는 Onnozok R-10보다 Cellusoft 효소의 가수분해율이 효과적이었다. 제조된 수용성 식이섬유소의 분자량 분포는 약 1,200-348 사이에 존재하는 oligomer 형태의 소당류로 분포되어 있었다. 제조된 수용성 식이섬유소의 생리적 기능성을 검정하기 위해 실험동물은 Sprague-Dawley종 수컷을 이용하여 정상군과 고콜레스테롤식이 실험군으로 나눈 후 고콜레스테롤 실험군을 다시 섬유소 종류와 공급수준에 따라 섬유소를 공급하지 않은 무섬유식이군 (FF군), 시판 식이섬유소를 5%공급한군 (5P군) 10%공급한군 (l0P군) 제조 식이섬유소를 5% 공급한 군 (5M군) 10% 공급한 군(10M군) 등 각 10마리씩 6군으로 나누어 4주간 사육하였다. 식이섭취량은 섬유소공급군이 FF군에 비해 증가되었으며 체중증가량은 섬유소공급군에서 FF군에 비해 유의적 (p<0.05)으로 낮았다. 식이효율은 FF군에 비해 모든 식이섬유소군에서 유의적 (p<0.05)으로 낮았으며 특히 10% 공급군에서 가장 낮았다. 간 무게근 FF군에 비하여 식이섬유소 공급군에서 유의적 (p<0.05)으로 감소되었으며 소장 및 맹장무게는 정상군과 무섬유식이군에 비하여 식이섬유소 공급군에서 증가되었다. 혁청 GOT 활성은 식이섬유소 공급군이 FF군에 비해 유의적 (p<0.05)으로 저하되었다. GPT 활성은 정상군에 비해 무섬유식이군인 FF군에서 증가되었으며 섬유소 공급관들은 다소 감소되는 경향이었다. 간조직 중 GST 활성은 FF군에 비해 식이섬 유소 공급군 모두 활성이 증가되었다. 그리고 이러한 생리적 기능은 제조된 수용성 섬유소군이 시판 수용성 섬유소와 차이가 없었다. 결론적으로 제조된 수용성 식이섬유소와 시판되는 수용성 식이섬유소가 생리져 기능이 거의 비슷하고 무독성이 관찰됨으로써 신갈나무로부터 제조된 수용성 식이섬유소의 제조 방법이 우수하다고 볼 수 있다.