• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.47-54
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• 2008

To make up original defects of the wooden materials for decks, and to supply the wooden material for outdoor, we fabricated preservative treated plywood(PTP). Copper azole (CUAZ-1) preservative was treated with a normal full-cell process. Bond Strength of PTP was not affected after the preservative treatment. The anti-fungal efficiency and dimensional stability were obtained from PTP. A little discoloration of the surface was detected, but the dimensional change or peel bonded area off were not observed after accelerated weathering test. Although some strength of PTP was reduced after 17 months of field exposure, the PTP should be applicable for outdoor applications.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.497-510
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• 2018

In this study, the decay resistance of larch wood, which was heat treated by superheated steam, was evaluated by the field decay test. During the field decay test of 12 months, non-treated wood has been severely damaged by termite, however, no visible damage has occurred in the preservative-treated wood and superheated steam heat-treated wood. Results of field decay test showed approximately 5% mass loss of the non-treated wood and the preservative-treated wood, and approximately 1% mass loss of the superheated steam heat-treated wood. After the field decay test for 12 months, the residual amount of preservatives remaining in the preservative-treated wood was lower than that before the field decay test. It was considered that the preservative was partially eluted during the field decay test, and the mass loss of the preservative-treated wood was thought to be similar to that of the non-treated wood. Through this study and additional long-term monitoring test, superheated steam heat treatment can be considered to be an environmental-friendly method to enhance the decay resistance of wood against rot fungi and/or insect without chemical treatment such as preservative injection.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.234-237
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• 2006

방부 목재는 일반 목재에 비해 사용 수명이 20-40년 정도 길기 때문에 사용이 점차 증가하고 있다 국내에서 가장 널리 사용되는 방부제는 chromate copper arsenate(CCA)이다 CCA 성분인 구리, 크롬 및 비소는 생태계 및 인체에 대한 위해성 때문에 많은 나라에서 처리 목재의 사용을 금지하거나 제한하고 있는 실정인 반면에, 국내에서의 사용은 늘어만 가고 있는 실정이다. 이 연구에서는 방부 목재를 사용하여 지은 3년 된 통나무집 한 곳과 8년 된 통나무집 두 곳에 인접한 토양시료를 채취, 분석하여 방부 목재 사용으로 인한 토양 오염도를 평가하였다. 건물에 인접한 지점부터 수평 방향으로 25cm 간격으로 100cm까지 5개의 표토 시료를 채취하였다. 또한 배경 농도를 알아보기 위해서 건물에서 조금 떨어진 곳에서 토양시료를 2개 채취하였다. 토양시료는 입도, 전기전도도, pH, 유기물 함량 등의 물리 화학적 성질에 대해 분석하였으며, CCA성분은 microwave oven을 이용하여 추출한 후 분석하였다. 0cm에서 CCA성분은 배경 농도보다. 높게 나타났다. 용출양은 3년 된 통나무집의 경우 크롬(67.2mg/kg)>구리(20.3mg/kg)>비소(4.14mg/kg)의 순으로 측정되었으며, 8년 된 통나무집의 경우 크롬(36.6mg/kg)>구리(21.3mg/kg)>비소(1.93mg/kg)의 순으로 측정되었다. 구리를 제외하고 크롬과 비소의 경우 3년 된 통나무집에서 많이 용출되는 것을 알 수 있었다. 3년 된 통나무집의 구리와 크롬은 100cm농도가 배경농도보다. 높게 나타났으며, 비소의 경우는 100cm농도가 배경농도보다. 낮게 나타났다. 이는 구리와 크롬이 100cm이상으로 이동을 한다는 것을 알려주며, 8년 된 통나무집의 경우는 크롬과 비소가 100cm이상으로 이동한다는 것을 알 수 있었다. 이 연구를 통해 CCA로 처리된 방부목재에서는 CCA성분이 용출되는 것을 알 수 있었으며, 크롬과 비소의 경우는 초기에 많이 용출되고, 구리의 경우는 꾸준히 용출되는 것을 알 수 있었다. 3년 된 통나무집이 8년 된 통나무집보다. 용출양이 더 컸으며, 이는 CCA성분이 초기에 많이 용출된다는 것을 의미한다.

• Journal of Oral Medicine and Pain
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• v.36 no.1
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• pp.1-10
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• 2011

The aims of this study were to establish the effect of gender and age on number of fungiform papillae and electrogustometric thresholds of the tongue, and to determine the relation between number of fungiform papillae and electrogustometric threshold. Sixty-two healthy subjects of 20 to 39 years old were enrolled in this study. Examination areas were defined as center, anterior, left lateral, right lateral, and posterior on the dorsal surface of the tongue, which was stained with methylene blue dye and photographed with a scale bar on it. The number of fungiform papillae within $1\; cm^2$ square area of each examination site was counted twice. The counted values were averaged to produce means. Taste thresholds were measured three times on each examination area using an electrogustometer. Means of the threshold values were calculated. 1. The number of fungiform papillae was the largest at the anterior examination area, followed by right lateral, left lateral, posterior and central. Women had more fungiform papillae than men at anterior, right lateral, and center areas. Subjects in twenties showed more fungiform papillae than those in thirties at anterior, right lateral, and left lateral areas. 2. Anterior area of the tongue measured the lowest electrogustometric threshold, followed by left lateral, right lateral, posterior and center. The threshold was higher in men at anterior and right lateral areas. The subjects in thirties had higher threshold only at right lateral area than those in twenties. 3. Electrogustometric threshold was inversely correlated with the number of fungiform papillae at anterior and posterior areas. The results showed that the number of fungiform papillae and taste threshold varied according to tongue locus, and they were influenced by age and gender. The results also suggested that the number of fungiform papillae was related to electrogustometric threshold inversely.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.101-107
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• 2005

One way of using wood safely and soundly for a long time is use of preservative-treated wood. Although, preservative-treated wood present to us durability and safety during using periods, it is also important to safe disposal after its service periods because of toxic components. Biological methods could be applicable to its disposal methods and better safe than chemical methods in the aspect of environmental problems. This study applied biological methods to remove the heavy metals from end-used CCA treated wood. The Aspergillus niger was used for this study which make black stain on the wood surface by it's spore. This study investigated the growing of A. niger on the CCA treated wood chips and the removal efficiency of heavy metals from CCA treated wood chips using immobilizing A. niger. A. niger could growing on the CCA treated wood chips and A. niger remove the effective elements of CCA treated wood effectively.

• Journal of the Korean Wood Science and Technology
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• v.39 no.6
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• pp.521-530
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• 2011

Nowadays, market demand of structural Glulam is growing and diversifying. The durability of Glulam should be significantly considered when they are intended to apply for out-door use such as timber bridge and pergola. This study was aimed to develop the manufacturing process of preservative treated structural Glulam using domestic softwood species. 10 m long structural Glulam were manufactured from domestic pitch pine logs with CuAz-3 preservative treatment. At each manufacturing process, the production yield was evaluated. Finally, bending tests were performed to verify the structural performance of manufactured Glulam. From the results, it was shown that the preservative treatment process hardly influenced on the production yield. But domestic pitch pine was proved to not be suitable for making the preservative treated Glulam due to the large difference of preservative permeability between sapwood and heartwood.

• Journal of the Korean Wood Science and Technology
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• v.31 no.4
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• pp.38-43
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• 2003

This is the second in a series of reports on the evaluation of weathering durability of waterborne preservative treated wood by accelerated weathering. The leaching of copper from ACQ-, CCA-, and CuAz-treated samples during weathering was increased by UV irradiation, when compared between full weathering and water-only weathering. The FTIR spectra of the weathered ACQ-, CCA, CuAz-treated samples at 1731 cm^-1, 1625 cm^-1, 1510 cm^-1, which are related to the fixation of copper, were different from those of unweathered controls. This result means that UV irradiation can weaken the chemical bond between lignin and copper and/or extraction of lignin-copper complex can be occured when lignin erode away by weathering.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.2
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• pp.111-115
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• 2007

It is inevitable to use germicidal agents like parabens, imidazolidinyl urea, phenoxyethanol and chlorphenesin to preserve the cosmetics. Although effective in reducing microblological contamination, chemical preservatives are irritative, allergenic and even toxic to human skin. So it is needed to decrease or eliminate usage of preservatives in cosmetic products Glycerin, butylene glycol (BG), prorylene glycol (PG), and dipropylene glycol (DPG) are widely used in cosmetics as skin conditioning agent or solvents. At high concentrations, they have antimicrobial activities, but deteriorate product quality like sensory feeling or safety. The purpose of study is to evaluate the effects of polyols on antimicrobial and preservative efficacy and confirm whether using adjusted polyols can decrease the contents of preservatives without deterioration of the quality of cosmetics. Effects of common polyols on antimicrobial activities of general preservatives were measured. BG and PG significantly (p < 0.05) increased activities of preservatives, but glycerin influenced little. It was inferred from the regression analysis of the results with S. aureus that adding 1% of PG increased activities of preservatives up to $2.1{\sim}8.4 %$ and BG improved activities of preservatives up to $1.8{\sim}8.4 %$. The challenge test results for oil in water lotions and creams showed that BG and PG improved the efficacy of preservative systems up to 40 % at a range of $5.5{\sim}9.9 %$, but glycerin had little effect on it. The measured rates of improvement were analogous to the inferences from regression analysis. It can be concluded that is possible to reduce total chemical preservatives up to 40 %, consequently improve the safety and sensory quality of cosmetics with the precision control of polyols. Added to that, using this paradigm, low preservative contents, praraben-free system, and even preservative-free systems can be expected in the near future.

• 학교보건
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• s.15
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• pp.38-40
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• 1986

• Fire Science and Engineering
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• v.25 no.3
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• pp.119-124
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• 2011

In this study, we measured the smoke density characteristics to find the fire risk of Wood-Plastic composites (WPCs) which are one of spotlighting materials for landscape architecture and residential construction material with the cone calorimeter tester (by ISO 5660-2) and the smoke density tester (by ASTM E 662). In addition, the identical test was implemented to compare the smoke density characteristics between the red pine and the antiseptic wood. The result of cone calorimeter test showed that emissions of carbon monoxide, carbon dioxide and total smoke production rate of WPCs were higher than those of red pine and antiseptic wood. And the result of smoke density test showed that maximum specific optical smoke density(Dm) of WPCs was higher than that of red pine and antiseptic wood as well.