• Journal of the Korean Wood Science and Technology
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• 제31권6호
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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.

• Journal of the Korean Wood Science and Technology
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• 제24권3호
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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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• 제23권3호
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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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• 제27권1호
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• pp.18-23
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• 1999

3회축을 갖는 Na-cellulose II의 형성조건을 X선회절법을 이용하여 검토하였다. 그 결과 Na-cellulose II는 Na-cellulose I 을 거쳐서 형성되며 결정중의 알칼리농도가 Na-cellulose I 이나 III보다 높은 조건에서 형성되는 것으로 생각되었다. 2회축에서 3회축으로의 섬유주기의 급격한 변화는 알칼리 처리 후의 수분제거방법에 의해 크게 영향받는 것으로 생각되었다. 동(銅)-알칼리셀룰로오스 복합체의 결정은 팽윤상태에서 안정된 구조를 가지며 건조에 의해 결정구조가 변화되었다.

• Journal of the Korean Wood Science and Technology
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• 제20권1호
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• pp.38-45
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• 1992

Fine and alkali-swollen structures of native cellulose fibers were investigated by x-ray diffraction methods. The results of fine structures are shown in Table 1. In meridional x-ray diffractograms, the relative intensity ratio R of (002) to (004) for cellulose I was ca. 0.05 and for regenerated cellulose it was ca. 0.45. It was considered that the transformation from cellulose I to cellulose II resulted from the packing or conformational change of cellulose chain. Finally. although cellulose I was not detected in the alkali-swollen celluloses treated for 1 hr to 24 hrs, washing and drying them resulted in the generation of considerable amounts of cellulose I and the amount decreased with increasing alkali duration.

• KSBB Journal
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• 제13권2호
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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.

• Asian-Australasian Journal of Animal Sciences
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• 제6권3호
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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.

• 한국염색가공학회지
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• 제5권3호
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• pp.221-228
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• 1993

Cellulose acetate and methyl cellulose were synthesized from waste cellulose in order to make waste knit on value added highly. Crystal waste cellulose by oxidation using $HIO_4$ and then acetylation was decrystallized. A degee of crystallinity was measured by X-ray diffraction and the structure was identified by FT-IR spetroscopy, respectively. Cellulose acetate was prepared from the reaction of decrystallized cellulose with acetic acid, cone-$H_{2}SO_{4}$ and acetic anhydride. Also, structure identification by FT-IR and a degree of crystallinity by X-ray diffraction were performed. DS of the synthesized cellulose acetate was 2.8 and viscosity average molecular weight was 238,000. Also, methyl cellulose was synthesized by treating cellulose acetate with NaOH and iodomethane. DS of the synthesized methyl cellulose was 3.0. Glucose unit with three hydroxy groups was all substituted by methoxyl groups. It was identified by FT-IR spectroscopy. Also, the thermal properties of the synthesized methyl cellulose were examined by DSC. It shewed two shewed melting peaks at 22$0^{\circ}C$ and 24$0^{\circ}C$ in the 2nd scan. It proved that DS=3.0 of methyl cellulose was a thermotropic liquid crystal.

• 한국잠사곤충학회지
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• 제19권1호
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• pp.5-7
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• 1977

누에인공사료의 조성중 필수적인 cellulose성분을 천연의 자원에서 개발하기 위해 뽕나무가지, 미류나무가지, 리기다소나무와 이태리포프라의 펄프분말, 왕겨, 톱밥, 볏짚등을 대상으로 실험하였다. 실험결과 뽕나무가지와 리기다소나무펄프가 인공사료의 cellulose대치 가능 자원임이 밝혀졌다. 특히 뽕나무가지의 화학적인 처리방법에 의하여 누에성장발육에 보다 유용한 제품을 얻을 수 있었고, 나아가서 장차 인공사료개발에 cellulose원으로서의 역활을 기대할 수 있게 되었다.

• 산업기술연구
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• 제36권
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• pp.33-37
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• 2016

Cellulose binding domains (CBDs) of cellulases are thought to assist in the hydrolysis of insoluble crystalline cellulose. To gain sufficient amount of CBDs, the self-cleavable intein tag was used for expression and purification of Trichoderma reesei cellobiohydrolase I CBD in E. coli. Synthetic CBD genes, CBD or linker-CBD were cloned into expression vector pTYB11. Recombinant CBDs were successfully purified by intein mediated purification with an affinity chitin-binding domain. The final yields of recombinant CBD and linker-CBD were 3.2 mg/L and 1.4 mg/L, respectively. The functional bindings of recombinant CBDs were confirmed by Avicel binding experiments. The simple and easy purification method using self-cleavable intein tag can be further used in pretreatment of crystalline cellulose or characterization of engineered CBDs.