• Title/Summary/Keyword: Na-cellulose

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Formation Conditions of Na-cellulose II with Three Fold Helix (3회나선축을 갖는 Na-cellulose II의 형성조건에 관한 고찰)

  • Kim, Nam-Hun;Lee, Myoung-Ku
    • Journal of the Korean Wood Science and Technology
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    • v.27 no.1
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    • pp.18-23
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    • 1999
  • The formation conditions of Na-cellulose II with three fold helix were investigated by an x-ray diffraction method. Na-cellulose II was formed through Na-cellulose I. It seems that the concentration of sodium hydroxide in Na-cellulose II is higher than both those of Na-cellulose I and Na-cellulose III. Na-cellulose II was formed well by different rinsing and drying methods even though the sample treatment was carried out in very short periods of time. Metal-complexed Na-cellulose swollen in the mixture of $Cu(OH)_2$ and sodium hydroxide is stable in wet state, and changed to a different polymorph by drying.

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Mercerization of Wood: Formation and Reversibility of Na-cellulose I in Reaction Wood

  • Kim, Nam-Hun;Kim, Dae-Young
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.6
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    • pp.1-7
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    • 2003
  • The phase transformation from cellulose I into cellulose II in woods by way of Na-cellulose I was examined by x-ray diffraction analysis.The formation of Na-cellulose I in woods increased with the increase of treating time in alkali solution. When compression wood was treated with 20% NaOH solution at room temperature for 1 day, the x-ray diagram showed only Na-cellulose I. On the other hand, the x-ray diagram of tension wood showed a mixture of cellulose I and Na-cellulose I. Cellulose I of tension wood could not be transformed completely into Na-cellulose I even after 10-day treatment, but was transformed into Na-cellulose I after 30-day treatment. Na-cellulose I of compression and tension woods was converted to the cellulose I pattern and the mixture of cellulose I and cellulose II, respectively, after washing with water and drying at 20℃. Cellulose I regenerated from Na-cellulose I in wood could not be converted to cellulose II by delignification. Thus, it revealed that the delignification of the alkali-treated wood did not affect their cellulose structures. From the results, therefore, it can be concluded that lignin in woods prevents the formation of the stable Na-cellulose I and the conversion from cellulose I to cellulose II. This means that the conversion of chain polarity of wood cellulose hardly occurs during mercerization because cellulose microfibrils are fixed by lignin which not to be intermingled.

X-ray and Electron Diffraction Study of Cellulose Crystal Structures (X선 및 전자선회절법에 의한 천연셀룰로오스의 결정구조 해석)

  • Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.24 no.3
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    • pp.72-79
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    • 1996
  • Cellulose I에서 Cellulose II로의 결정변태기구를 X선 및 전자선 회절법과 현미경적 방법을 이용하여 구명하였다. X선 회절 결과, Na-cellulose I을 고온에서 수세할 경우 Cellulose I과 Cellulose II의 혼합형 회절도가, 저온에서 수세할 경우 Na-cellulose IV의 회절도가 얻어졌다. 전자선회절 결과, 고온수세의 시료는 Cellulose I과 Cellulose II의 혼합형이 저온수세의 시료는 Cellulose II의 회절도가 얻어졌다. 또한 고온수세 시료의 전자선회절도로부터 섬유벽의 내측부가 외측부보다 재생 Cellulose I의 양이 많은 것이 확인되었다. 따라서 알칼리 팽윤시 섬유벽내에는 불완전한 팽윤이 발생하는데 그 정도는 내측부가 더욱 심한 것으로 생각된다. 이때 형성되는 불완전한 Na-cellulose I 은 고온 수세의 경우는 탈수에 의해 Cellulose I로, 저온수세의 경우는 수화에 의해 Cellulose II로 변태되지만 완전히 팽윤된 Na-cellulose I은 Cellulose I로 재생될 수 없는 것으로 생각된다. 현미경적 실험결과, mercerization과정에서 cellulose 분자쇄의 packing이나 conformation의 변화와 관련하여 microfibril 의 흐트러짐은 발생하지 않는 것으로 생각되었다.

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Adsorption Behavior of Metal ions by Na-Cellulose (Na-셀룰로스에 대한 금속이온들의 흡착성에 관한 연구)

  • Lee, Tack-Hyuck;Yoon, Koog-Joong
    • Analytical Science and Technology
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    • v.7 no.3
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    • pp.271-276
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    • 1994
  • A Na-cellulose adsorbent was prepared by treating Sigma S-5504 cellulose with 2M NaOH and examined the adsorption behavior between metal ions and Na-cellulose in aqueous solution with batch method. Considering ion exchange capacity of Na-cellulose, the adsorption ratio of the Na-cellulose to metals charge equivalent indicated that the adsorption result from ion exchanging between metal ions and Na-cellulose. The enthalpy for the metal adsorption on the Na-cellulose was calculated to -18kcal/mol, which value was compared to those of carboxymethylcellulose(CMC) and Dowex 50W-X8, these result suggested that the adsorption on Na-cellulose resulted from ion exchange adsorption.

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A Study of Recycle of Waste Wood After Cultivating Oak Mushroom (II) - On the Structure of Cellulose Crystal Transformation of the Waste Wood - (표고버섯골목의 재활용에 관한 연구 (II) - 폐골목 세포벽 중의 셀룰로오스 결정의 변태구조 -)

  • Kim, Nam-Hun;Lee, Won-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.23 no.3
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    • pp.1-7
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    • 1995
  • The crystal transformation from cellulose I to cellulose II during alkaline swelling of waste wood, which has been used for cultivating oak mushroom(Cortinellus edodes (Berk.) Ito et Imai), was investigated and compared to that of normal wood by a series of X-ray diffraction analysis. When the sapwood of cultivated wood was treated with 20% NaOH solution for 2 hours, the cellulose I can be easily transformed into Na-cellulose I than normal wood or heartwood of cultivated wood. Certainly the formation of Na-cellulose in wood is proportional to alkali swelling duration, and the formation of cultivated sapwood was faster than that of the other woods. Cellulose I in the sapwood of cultivated wood was easily transformed into cellulose II during mercerization, but the sapwood of normal wood and the heartwood of cultivated wood hardly converted to cellulose II. Namely, most of Na-cellulose I in normal wood can be reconverted to cellulose I in the process of washing and drying. Therefore, it can be concluded from this study that in cell wall lignin and hemicellulose can prevent the alkaline swelling of cellulose in wood and the transformation from cellulose I to cellulose II as well.

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Preparation of Regenerated Cellulose Fiber via Carbonation (II) - Spinning and Characterization -

  • Oh Sang Youn;Yoo Dong Il;Shin Younsook;Kim Hak Yong;Kim Hwan Chul;Chung Yong Sik;Park Won Ho;Youk Ji Ho
    • Fibers and Polymers
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    • v.6 no.2
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    • pp.95-102
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    • 2005
  • Sodium cellulose carbonate (CC-Na) dissolved in $8.5\;wt\%$ NaOH/ZnO (100/2-3, w/w) aqueous solution was spun into some acidic coagulant systems. Diameter of regenerated cellulose fibers obtained was in the range of $15-50\;{\mu}m$. Serrated or circular cross sectional views were obtained by controlling salt concentration or acidity in the acid/salt/water coagulant systems. Velocity ratio of take-up to spinning was controlled up to 4/1 with increasing spinning velocity from 5 to 40 m/min. Skin structure of was developed at lower acidity or higher concentration of coagulants. Fineness, tenacity and elongation of the regenerated cellulose fibers were in the range of 1.5-27 denier, 1.2-2.2 g/d, and $8-11.3\;\%$, respectively. All of CC-Na and cellulose fibers spun from CC-Na exhibited cellulose II crystalline structure. Crystallinity index was increased with increasing take-up speed.

Morphological and Physicochemical Changes of NBKP by Alkali Pretreatment (알카리 전처리에 의한 NBKP의 형태학적 및 이화학적 변화)

  • Mun, Sung-Phil;Jang, Min-Hwan
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.41 no.4
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    • pp.58-64
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    • 2009
  • This study was carried out to prepare high porosity pulp for oil and air filter media from commercial grade NBKP with 6 - 20% NaOH treatment. The fiber width of NBKP remarkably decreased by NaOH pretreatment. The air permeability of the test sheet prepared from alkali-pretreated NBKP increased with increasing NaOH concentration up to 15%. The burst factor was greatly decreased by alkali pretreatment. By 15 - 20% NaOH pretreatment of NBKP, it could be possible to prepare a high porosity pulp. It seems that the high porosity of the pulp was due to a strong swelling and a great change of the cellulose crystalline lattice from cellulose I to cellulose II with NaOH treatment of NBKP. The study suggested that alkali- pretreated NBKP could be used for manufacturing oil and air filter media.

Combined Effects of Sodium Substitution and Addition of Cellulose or Chitosan on Quality Properties of Pork Sausages

  • Jin, Sang Keun;Hur, Sun Jin;Yim, Dong Gyun
    • Food Science of Animal Resources
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    • v.39 no.4
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    • pp.555-564
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    • 2019
  • The aim of this study was to assess the impacts of cellulose/chitosan addition in combination with sodium substitution, including KCl and $MgCl_2$, on the quality and sensory properties of sausages. Sausages (control, 100% NaCl; T1, 60% NaCl, and 40% KCl; T2, 50% NaCl, 40% KCl, and 10% $MgCl_2$) were formulated with cellulose/chitosan at concentrations of 3% and compared to control. T1 and T2 decreased the pH values (p<0.05), while the use of cellulose increased these values. Biopolymer addition reduced lipid oxidation (p<0.05). In sausages containing cellulose, volatile basic nitrogen (VBN) in T1 was lower than that in T2 (p<0.05). The use of cellulose increased L*-, a*-, and W color values in T1 (p<0.05). Furthermore, cellulose addition was associated with lower hardness (p<0.05). Cellulose addition contributed to better overall acceptability (p<0.05). Consequently, a combined mixture containing T1 and cellulose appears to be the best combination, indicating a possible synergistic effect.

Fine Structure and Physical Properties of Cotton Fibers and their Fabrics Treated with Liquid Ammonia, NaOH, and NaOH/Liquid Ammonia (액체암모니아, 수산화나트륨, 수산화나트륨/액체암모니아 처리한 면의 미세구조 및 물성)

  • 배소영;이문철;김홍성;이영희;김경환
    • Textile Coloration and Finishing
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    • v.6 no.2
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    • pp.47-54
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    • 1994
  • Cotton fiber, NaOH-mercerized cotton fiber, cotton fabric, and NaOH-mercerized cotton fabric have been treated by liquid ammonia at -33.4$^{\circ}C$. The fine structures, bending properties, tensile strengthes, shrinkages for laundering, and wrinkle recoveries were studied. The treatment of cottons with liquid ammonia brought about the transition of crystal lattice ; transforming cellulose I crystal of original cotton to cellulose I and III crystal, and cellulose II crystal of mercerized cotton to cellulose II and III crystals. The degree of crystallinities were decreased in the order of liquid ammonia>NaOH/liquid ammonia>NaOH-treated cotton. However moisture regain and water absorbency for liquid ammonia-treated cotton were lower than that of NaOH-treated cotton because of a difference in swelling actions of the agents. It seems caused by intermicrofibrillar pores produced in swelling processes. The bending rigidity and bending hysteresis were decreased remarkly by liquid ammonia treatment. Therefore softness and dimensional stability were improved. The liquid amminia and NaOH/liquid ammonia-treated cottons moreover show excellent properties in tensile strength, anti-shrinkage for laundering, and wrinkle recovery.

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Study on the Extracted Cellulose Powder from Natural Resources for Artificial Diet of Silkworm, Bombyx mori (II) (누에 인공사료의 Cellulose원 개발에 관한 연구(II))

  • 김주읍;박광의;성수일;유재복
    • Journal of Sericultural and Entomological Science
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    • v.19 no.1
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    • pp.9-13
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    • 1977
  • This experiment was carried out to know relationship between economical characters and kinds of extracted cellulose powders, extracting methods and cellulose composition. The results obtained are summarized as follows; 1. Among the matters for cellulose resources, mulberry branch is the most useful in economical characters such as larval weight, ratio of cocoon shell and mortality, followed by pine branch. 2. Though both PA-method and NaOH-treatment are equally effective in the larval growth, the latter may be more recommendable because of its economical convenience. 3, It may be desirable to add 15 to 22.5 per cent of cellulose powder per dry matter in the diet composition

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