• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.677-680
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• 2006

Tensile as well as flexural strengths of concrete can be substantially increased by introducing closely spaced fibers that would obstruct the propagation of microcracks, therefore delaying the onset of tension cracks and increasing the tensile strength of the material. Fibers of various shapes and sizes produced from steel, plastic, glass and natural materials are being used. In this study, we used cellulose chip fiber to decrease the shrinkage crack in mortar and concrete. Specially, we have studied the dispersion characteristic of cellulose chip fiber. As a result, it was assumed that the slurry type of cellulose chip fiber is very effective to disperse the fiber in mortar and concrete.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.9_10
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• pp.1144-1152
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• 2003

Kenaf has been cultivated in Jeju Island. After being harvested at 105 DAP(day after planting) and separated from kenaf stalks , decorticated kenaf basts were treated with different concentration/temperature/time combinations in order to do chemical rotting. The following fiber properties were compared; rotting effects, colors, crystallinity, molecular structures, dyeabilities, and non-cellulose contents such as pectins, lignins, & hemicellulose. The best results of chemical rotting were obtained from the specimens treated with low concentration/ low temperature/short time. Their colors were bright yellow. The lumens of specimens diminished with the affect of NaOH. The structures of chemically rotted kenaf fibers were cellulose 1. The degree of crystallinity of chemically retted kenaf fibers were very high. Non-cellulose content, especially hemicellulose, was low in the specimens treated with the high NaOH concentration. Dyeabilities of kenaf fibers were higher among the specimens without the non-cellulose content than those with the non-cellulose content.

• International Journal of Advanced Culture Technology
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• v.3 no.1
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• pp.52-60
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• 2015

The present study aims to the use of carboxymenthyl cellulose (CMC) improving the ability of fiber in the dyeing process. Cellulose was extracted from banana leaves by NaOH and then modified by reacting with chloroacetic acid to obtain the carboxymenthyl cellulose. The effect of carboxymenthyl cellulose contents on the mechanical properties and dye absorption were also investigated. Then, CMC were blend with polypropylene (grade 561R) at 1%, 3% and 5% by weight ratio. The fibers were obtained from single screw extruder. The results show that the mechanical properties of the product decreased when increased the amount of CMC in the fiber product. After dyeing, the dye however were absorbed by the CMC-PP fibers more than the original PP fibers. The absorption of dye on the CMC-PP fibers increased significantly with the CMC ratio.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.551-559
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• 1996

To examine the effects of dietary fibers on gastrointestinal physiology, rats were fed with diets containing 10% sodium alginate,10% cellulose, or fiber-free diets for 5 weeks. The results obtained were as follows: The chronic consumption of sodium alginate induced a significant decrease in body weight gain and feeding efficiency, but a significant increase in length and weight of small intestine. Fecal bulk and weight were higher in fiber-fed group than fiber-free group. The chronic consumption of dietary fiber induced a significant increase in fecal output, resulting in tile decrease of apparent digestibility of protein and lipid. Pancreatic protease activity was lower in fiber-fed group than fiber-free group, whereas pancreatic amylase and lipase activities were not affected. Scanning electron microscopy(SEM) and light microscopy(LM) studies showed small intestine microvilli with numerous ridges and convolutions and goblet cells in fiber-fed groups. As a result of this study, it is concluded that the chronic consumption of dietary fiber decreases apparent digestibility of nutrients and induces morphological and biochemical adaptation of digestive organs.

• Carbon letters
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• v.18
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• pp.56-61
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• 2016

Cellulose fibers were stabilized by treatment with an electron-beam (E-beam). The properties of the stabilized fibers were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The E-beam-stabilized cellulose fibers were carbonized in N₂ gas at 800℃ for 1 h, and their carbonization yields were measured. The structure of the cellulose fibers was determined to have changed to hemicellulose and cross-linked cellulose as a result of the E-beam stabilization. The hemicellulose decreased the initial decomposition temperature, and the cross-linked bonds increased the carbonization yield of the cellulose fibers. Increasing the absorbed E-beam dose to 1500 kGy increased the carbonization yield of the cellulose-based carbon fiber by 27.5% upon exposure compared to untreated cellulose fibers.

• 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.

• Textile Coloration and Finishing
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• v.10 no.1
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• pp.38-42
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• 1998

Both cellulose and chitin together were dissolved in DMAc/LiCl and these solutions were extruded into coagulant of $DMAc/H_2O$. Fibers thus obtained were treated in NaOH aqueous solution. Results showed that the fiber surface contains celluose and chitosan. This means that these fibers treated are composed of three components, ie, cellulose, chitin, and chitosan. These fiber showed secure antibacterial and mechanical properties.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.215-218
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• 2001

이산화탄소($CO_2$)를 사용한 셀룰로오스 카보네이트 유도체의 제조 및 재생 셀룰로오스 섬유 제조와 관련한 기초 연구성과를 이미 발표한 바 있다[1~3]. 이번 연구에서는 일정한 조건에서 제조된 셀룰로오스 카보네이트 유도체의 용해온도, 셀룰로오스 카보네이트 함량, 10% 수산화나트륨 수용액내의 산화아연의 함량 변화에 따른 용해성을 평가하여 상그림표를 작성하였다. (중략)

• Journal of Nutrition and Health
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• v.28 no.9
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• pp.834-845
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• 1995

This study was conducted in order to establish an in vitro method simulating the physiological function of fibers along the large intestine of humans. Commercial fibers including guar gum, apple pectin, citrus pectin, CM-cellulose, alginic acid and $\alpha$-cellulose, and dietary fiber residues obtained from rice bran, barley, soybean, Korea cabbage, apple, tangerine and sea mustard were employed to determine the water-holding capacity, weight of hydrated residue and fiber content after anaerobic fermentation using human fecal inoculum for 24 hours, followed by dialysis under osmotic suction pressure. The weight of hydrated residue in commercial fibers was in the decreasing order of CM-cellulose > alginic acid, $\alpha$-cellulose > apple pectin, citrus pectin > guar gum and that in food fiber residues was in the decreasing order of rice bran, sea mustard > soybean > tangerine, Korean cabbage > barley > apple. It was demonstrated that the larger the weight of hydrated residue was, the more the weight of human stool increased. Consequently this in vitro method can be used as a preceeding test before undertaking animal or human experiment to predict the physiological effects of fiber residues from diverse food samples as well as commercially refined fibers.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.1-6
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• 1996

Cellulose fiber reinforced cement composites manufactured by the slurry-dewatering process have found broad applications in thin cement products as replacement for asbestos cement. This paper focuses on the durability characteristics of these composites under different aging conditions. The effects of wetting-drying and freezing-thaw cycles, carbonation, and exposure to hot and humid environments on the structure and properties of cellulose fiber-cement composites were investigated. The predominant mechanisms of aging in the composites were identified through investigation of structure-property relationships. Measures to control these aging mechanisms were diversed and evaluated. Refined cellulose fiber-cement composites are shown to possess excellent durability characteristics under the effects of various aging processes.