• Title/Summary/Keyword: Extractives

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Determining the Safer Thickness of the Epoxy Coating on Wooden Utensils (식품 안전성 확보를 위한 목재 식기용 에폭시 코팅의 두께 결정)

  • 이광수;임동길;김상엽;장미란;김우성;이영자
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.2
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    • pp.447-450
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    • 2004
  • Overall migration through epoxy layer coated wood was investigated to estimate the coating thickness satisfying the regulatory limit. As an index of overall migration, KMnO$_4$ oxidizable extractives by the food simulant water solution was used. Migration pattern in interest range could described by a simple diffusion model and the temperature dependence of the permeability index could be explained by Arrhenius equation. The thickness of epoxy coating greater than 0.004 mm was analyzed to be required for satisfying the regulatory guideline.

Studies on the Utilization of Chestnut Bur(1) - Components of Chestnut Bur - (밤송이 이용(利用)에 관(關)한 연구(硏究) (1) - 밤송이 성분(成分) -)

  • Kim, Jae-Kwang;Kong, Young-To;Jo, Jae-Myeong
    • Journal of the Korean Wood Science and Technology
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    • v.15 no.4
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    • pp.59-63
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    • 1987
  • As the production of chestnuts from chestnut trees has been increased annually in the past several years in this country, developing the utilities of chestnut bur has been considered as one of main research problems. Therefore. in this paper, the chemical components were analysed to find a way of utilizing the chestnut bur. It was proved that chestnut bur is abundant in extractives (hot water 16.0%, 1%-NaOH 40.6%) and tannin content (16.5%). Of the tannin, the soluble tannin (3.2%) content is higher than condensed tannin (2.2%), and gallic acid content(3.3-3.9%) is slightly higher than ellagic acid(2.8-3.0%), For more effectively utilizing as a tannin resources, the chestnut bur should be collected immediately after yield of chestnuts, maybe in October every year.

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A study on recycling of cast as adsorbent (흡착제로서 분변토 재활용에 관한 연구)

  • 손희정;전성균;하상안
    • Journal of environmental and Sanitary engineering
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    • v.15 no.3
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    • pp.44-49
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    • 2000
  • The purpose of this research is to evaluate the adsorption capacity of casts for heavy metals. The casts were excreted by earthworm, Lumbricus rubellus, after having eaten the paper sludge. Various batch experiments on adsorption were performed to compare cast and activated carbon. The pH increase in solution due to extractives from cast was 1.3 and the cation exchange capacity which implies adsorption capacity for solubles is greater on activated carbon than on cast. According to the results of batch experiment, the removal rates of Pb, Cu, Cr, Zn using the activated carbon and casts as adsorbent were 98%, 93%, 94%, 89%, 82% and 95%, 90%, 88%,80%, 66%, respectivity, and this removal were achived less than 90 minutes. It can be said that casts is so good adsorbent as activated carbon is, although adsorption carbon was found to be some large than those of casts through Freundlich isotherm applied for adsorption of soluble. As a result on the experiment of isothermic adsorption from the mixed component solution in the batch, the order of preferable elements in heavy metal adsorption was found to be Pb>Cd>Cu>Cr>Zn on activated carbon, respectively.

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Chemical composition and Energy contents analysis of Seven Clones of Salix hultenii as short-rotation forestry candidate (단벌기 순환림 후보 호랑버들 7 클론의 화학적 조성과 에너지 함량)

  • Shin, Soo-Jeong;Kim, Yong-Sang;Yeon, Ik-Jun;Han, Sim-Hee
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.436-438
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    • 2009
  • To evaluate short rotation forestry candidates, seven clones of Salix hultenii were investigated as focused on chemical compositions and energy contents. There were significant variations in chemical compositions and energy contents among different clones. Variations in hot-water extractives content were 6.6-16.0% and 19.6-25.4% variation in lignin content. In carbohydrate compositional analysis, xylan contents were 7.5-13.1% with variation among different clones. Higher heating values were 17.69-20.02 MJ/kg.

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New Korean Traditional Papermaking from Morus spp.(I)-Anatomical and Chemical Properties and Pulping Characteristics- (뽕나물 이용한 새로운 한지의 제조(제 1보)-해부학적 , 화학적 성밀 및 펄프화 특성-)

  • 최태호
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.3
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    • pp.96-104
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    • 1999
  • Anatomical and chemical properties of three mulberry species (Morus spp) were analyzed as an alternative row material for the paper mulberry (Broussonetia kazinoki) . The pulping and papermaing characteristics of bast fiber and whole stalks by three different pulping processes, conventional alkali, alkali-hydrogen peroxide, and sulfomethylated, for the Hanji were investigated. The fiber dimension of M.bombycis was the biggest of the species. The fiber length of upper part and the fiber width and cell wall thickness of lower part were bigger than the others. The extractives and ash contents of bast fiber were higher than those of whole stalk , and holocellulose and lignin contents of whole stalk were higher than those of bast fiber. The pulp yields of M.alba bast fiber, M.bombycis whole stalk, and sufomethylated pulping were higher than the others.

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Characteristics of Traditional Papers of South China (중국 남부지역 전통종이의 이화학적 특성 비교.분석)

  • Cho, Jung-Hye;Eom, Tae-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.41 no.4
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    • pp.1-7
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    • 2009
  • One commercial Xuanji and five traditional paper which were made in south china were collected and its chemical, physical, optical properties were investigated and compared to those of Hanji. Extractives(cold, hot, 1% NaOH and Alcohol-benzene) of bamboo paper had higher contents compared with other papers. Strength properties had been highest Hanji, but had been lowest Xuanji 1 and 2. Brightness of all paper were decreased as following order; Xuanji, Hanji, Thai paper, bast paper 1, bast paper 2, Dongpa paper, bamboo paper.

Preliminary Study on Automation of Bark Peeling Process for Paper Mulberry (닥나무 흑피제거 자동화 공정 기초연구)

  • Kwon, Oh-Hun;Kim, Hyun-Chel
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.4
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    • pp.59-66
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    • 2011
  • This study was carried out to develop the automation bark peeling process of paper mulberry for making Hanji. Nowadays, almost raw material has been imported from south-east asia for making Hanji. Raw material dependence is very high for Hanji-making by low productivity in korea. This study is focused on the resolution for problem of bark peeling automation. Water and sand jet of compressed air was possible bark peeling for black bast fiber. The effect of removing black bast fiber increased the longer the steaming time. Also using drum of bark peeling showed that results under temperature $80^{\circ}C$ and Rpm 50/min were best bark peeling and separating bast fiber from stem. The contents of holocellulose, lignin, ethanol-benzene extractives, and ash were 91.63~95.55%, 1.4~2.0%, 1.12~1.65%, and 1.4~4.3%, respectively. Chemical characteristics are similar between imported raw-material with drum bark.

Flavonoid Glycosides from Needles of Taxus cuspidata(Taxaceae) (주목 잎의 후라보노이드 배당체)

  • Ham, Yeon-Ho;Park, Wan-Geun;Han, Sang-Sup;Bae, Young-Soo
    • Journal of the Korean Wood Science and Technology
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    • v.25 no.2
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    • pp.45-51
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    • 1997
  • 주목 잎을 채취하여 건조하고 아세톤-물 (7 : 3, v/v) 의 혼합액으로 추출한 후 에틸아세테이트 및 수용성 부분으로 분리하고 Sephadex-LH 20으로 충진한 칼럼을 이용하여 2개의 flavan 단량체와 2개의 후라보노이드 배당체를 단리하였다. 에틸아세테이트용성 추출물은 대부분 (+)-catechin 과 (-)-epicatechin으로 구성되어 있었으며 수용성 부분에서는 quercetin-3-0-arabinopyranosyl-($1"'{\rightarrow}6"$)-${\beta}$-D-glucoside와 quercetin-3-O-rutinoside 인 두 개의 탄수화물로 구성된 배당체를 분리하였으며 주목에서는 이들 화합물은 아직 보고된 바가 없다. 이들의 구조결정을 위하여 박층크로마토그래피를 실시하고 $^1H$-NMR과 $^{13}C$-NMR 스펙트럼을 기존의 스펙트럼과 비교, 분석하여 정확한 구조를 규명하였다.

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Flavonoid Glycosides from Needles of Larix leptolepis(Pinaceae) (일본잎갈나무 잎의 후라보노이드 배당체)

  • Kim, Jin-Kyu;Park, Wan-Geun;Bae, Young-Soo
    • Journal of the Korean Wood Science and Technology
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    • v.25 no.2
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    • pp.81-87
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    • 1997
  • 일본잎갈나무잎을 채취하여 아세톤 : 물 (7 : 3, v/v) 의 혼합용액으로 추출한 후 에틸아세테이트용성 화합물과 수용성 화합물로 분리하였으며 Sephadex LH-20으로 충진한 칼럼을 사용하여 화합물을 단리 하였다. 단리 화합물을 확인하기 위하여 셀룰로오스 박층 크로마토그래피(TLC)를 실시한 후 자외선 램프 하에서 관찰하였다. 바닐린 발색제를 분무히여 정색반응을 조사하고 $R_r$ 값을 구하였다. 단리된 화합물들의 구조는 $^1H$-NMR과 $^{13}C$-NMR 스펙트럼을 이용하여 그 구조를 규명하였으며 에틸아세테이트용성 화합물에서는 (+)-catechin, (-)-epicatechin, kaempferol-O-arabinofuranoside와 kaempferol-3-O-arabinopyranoside, 수용성 화합물에서는 apigenin-8-C-rhamnosyl-($1"'{\rightarrow}2"$)-glucoside(2"-O-rhamnosylvitexin)을 단리 하였다.

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Biodegradability and Risk Assessment of Biomass-based Polymeric Materials

  • Han, Song Yi;Park, Chan Woo;Jang, Jae Hyuk;Lee, Seung Hwan
    • Journal of Forest and Environmental Science
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    • v.31 no.4
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    • pp.297-302
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    • 2015
  • With the intention to solve environmental problems caused by synthetic plastics from petroleum resources, biodegradable polyurethane foams and thermosetting moldings were prepared from biomass, such as wood and wheat bran by liquefaction method. Biodegradability of these biomass-based polymeric materials was investigated. In activated sludge, polyurethane foams from liquefied wheat bran and thermosetting molding from phenolated wood were decomposed approximately 14% and 29% for 20 days, respectively. One of the wood fungi, Coriolus versicolor was able to grow without supplemental nutrition, only with distilled water and polyurethane foam as a nutrition source. Risk assessments were also conducted and results showed that estrogenicity, mutagenicity, and carcinogenicity were not observed in the extractives of biomass- based polymeric materials.