• 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.

• 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.

• 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.

• 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.

• Analytical Science and Technology
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• v.10 no.4
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• pp.291-299
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• 1997

2,2'-iminodibenzoic acid-cellulose was prepared by reacting 2,2'-iminodibenzoic acid salt with cellulose-Cl obtained by chlorination of cellulose-OH which is the major component of sawdust. The adsorptivity of Pb(II) and Cu(II) was studied using the synthetic chelating adsorbent. The adsorption amounts of those ions increased with increasing pH and the optimum adsorption time of metal ion was about 1hr. The adsorptivity of Pb(II) was larger than that of Cu(II).

• Applied Chemistry for Engineering
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• v.35 no.4
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• pp.352-359
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• 2024

Environmental pollution from heavy metal ions (HMIs) is a global concern. Recently, biosorption methods using cellulose sorbents have gained popularity. The objective of this study was to assess the removal efficiency of Cu(II), Pb(II), and Hg(II) ions at low concentration levels (100-700 ppb) from aqueous solutions using three different cellulose fiber-based filter media. Sample A was pure cellulose fiber, Sample B was 10% activated carbon-cellulose fiber, and Sample C was cellulose fiber-glass fiber-30% activated carbon-20% amorphous titanium silicate (ATS). The samples were characterized by several physicochemical techniques. The porosity measurements using N₂ sorption isotherms revealed that Samples A and B are nonporous or macroporous materials, whereas the addition of 50% filler materials into the cellulose resulted in a microporous material. The Brunauer-Emmett-Teller (BET) surface area and pore volume of Sample C were found to be 320.34 m²/g and 0.162 cm³/g, respectively. The single ion batch adsorption experiments reveal that at 700 ppb initial metal ion concentration, Sample A had removal efficiencies of 7.5, 11.5, and 13.7% for Cu(II), Pb(II), and Hg(II) ions, respectively. Sample B effectively eliminated 99.6% of Cu(II) ions compared to Pb(II) (14.2%) and Hg(II) (31.9%) ions. Cu(II) (99.37%) and Pb(II) (96.3%) ions are more efficiently removed by Sample C than Hg(II) (68.2%) ions. The X-ray photoelectron spectroscopy (XPS) wild survey spectrum revealed the presence of Cu(II), Pb(II), and Hg(II) ions in HMI-adsorbed filter media. The high-resolution C1s spectra of Samples A and B reveal the presence of -C-OH and -COOH groups on their surface, which are essential for HMIs adsorption via complexation reactions. Additionally, the ATS in Sample C facilitates the adsorption of Pb(II) and Hg(II) ions through ion exchange.

• KSBB Journal
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• v.13 no.2
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• pp.162-167
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• 1998

The adsorption behaviors of two major cellulase components, endo I and exo II, from Trichoderma viride were investigated using $\alpha$-celluloses with different correlation crystallinity index(Cc) as substrates. The adsorption of cellulase enzyme components was significantly affected by the reaction condition and the physicochemical properties of the cellulose. The $\alpha$-cellulose was hydrolyzed in the presence of cellulase for various periods. The correlation crystallinity index of $\alpha$-cellulose increased with increasing the hydrolysis time. The adsorption was apparently found to obey the first-order kinetics, and the adsorption activation energy(Ea) was calculated from the adsorption rate constant(ka). The value of adsorption rate constant for endo I was larger than that of exo II. This means that endo I are adsorbed more rapidly than exo II. With the increase in correlation crystallinity index, the values of the adsorption rate constants for endo I and exo II decreased, respectively. The activation energy for the adsorption of exo II on the cellulose also was larger than that of endo I. Also adsorption activation energy of endo I and exo II increased with an increase in the crystallinity of sample cellulose.

• Journal of Pharmaceutical Investigation
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• v.36 no.6
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• pp.371-375
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• 2006

Neomycin coupled to a polymer matrix via a metal linker was prepared and evaluated for prolonging antibacterial activity. Microcrystallized cellulose was chemically modified to cellulose xanthate(MCX) to afford metal binding sites. MCX was treated with Cu(II), Fe(III) or Zn(II) followed by reaction with neomycin (Ne). The release of Ne from MCX-Zn(II)-Ne was investigated and its activity duration was measured by ditch plate method. The amount of metal bound to MCX was 0.36 mmol/g matrix, 0.26 mmol/g matrix and 0.56 mmol/g matrix for Cu(II), Zn(II) and Fe(III), respectively. Ne bound to MCX-metal chelates was 0.006 mmol, 0.07 mmol and 0.01 mmol per g MCX for Cu(II), Zn(II) and Fe(III), respectively. The Ne release from MCX-Zn(II)-Ne was sustained even after seven washes, whereas Ne from MC/Zn(II)/Ne mixture was almost completely released in two washes. Antibacterial activity was prolonged with MCX-Zn(II)-Ne and MCX-Fe(III)-Ne, but not with MCX-Cu(II)-Ne when compared with that of free Ne. Taken together, these results suggest that neomycin coupled to MCX via a proper metal linker has a potential as a polymeric antibacterial agent with sustained activity.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.3
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• pp.383-388
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• 1993

Three experiments were conducted to investigate the effect of cellulose addition on high (Exp. I) and low (Exp. II and III) dry matter barley straw silages. In Exp. I : 1 kg barley straw + 16 g glucose + 600 g water + 0 g as control (E0G), + 2 g (E2G), + 4 g (E4G), + 6 g (E6G), and + 8 g (E8G) of cellulose as treatments were ensiled. In Exp. II and III, 10 g glucose was and was not added, respectively, into 2 kg barley straw + 0 g (E8W, E8T) of cellulose as treatments. Samples were stored for 10 (Exp. I) and 7 (Exp. II and III) months at $21^{\circ}C$. The effect of cellulose addition on the fermentation and breakdown of the polysaccharides component in the silos at ensiling occurred more markedly at low dry matter silages rather than at the high ones. All cellulose treated silages were well preserved (pH below 5 in Exp. I and below 4 in Exp. II and III), while lactic acid and ethanol concentration increased. The fibrous fraction (ADF, NDF, crude fiber, hemicellulose, and cellulose) significantly (p<0.01) decreased (except hemicellulose content in Exp. I) compared with corresponding untreated silages. In vitro dry matter digestibility values (IVDMD) were similar for all silages. The present study showed that cellulose addition improved the potential nutritional and fermentation quality of barley straw silage.

• Textile Coloration and Finishing
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• v.5 no.2
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• pp.139-143
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• 1993

The effects of air-gap distance on properties of cellulose fiber spun from the 6 wt% solution of cellulose in monohydrate N-methylmorpholine N-oxide (NMMO) were investigated. The diameter of fiber spun was drastically reduced in 10 cm of air-gap distance at fixed drawing speed, however, no great change was observed beyond 40 cm. As the distance lengthened, the Cellulose II structure was first appeared and followed by Cellulose II and IV mixed morphology. Also the degree of crystallinity and the size of crystals were tending to decrease.