• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2004.04a
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• pp.181-191
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• 2004

• Journal of the Korean Applied Science and Technology
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• v.26 no.4
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• pp.428-433
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• 2009

Cellulose triacetate (CTA) was prepared from cotton linter and pulps which contain various contents of $\alpha$-cellulose. CTA which contains 2.8 of degree of substitution (DS) and 222 of degree of polymerization (DP) was obtained from V-81 pulp under the heterogeneous system. The DS was measured by the titration method, and the DP was obtained by measurement of viscosity. FT-IR spectometer (FT-IR 6300, JASCO) was used to analyze the chemical structure of raw materials and cellulose triacetate, and X-ray diffractometer (X-pert MPD PW3040, Philips) was used to confirm the crystal structure and to calculate the relative crystallinity index (RCI). As $\alpha$-cellulose content in pulp increased, the acetylation yield increased. Besides with a kind of pulp, it contains insoluble residue which was mainly formed due to the formation of glucomannan triacetate and xylan diacetate during the esterification.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.17-23
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• 2013

The reduction of metal ion from the cotton linter for the preparation of NMMO (N-methylmorpholine N-oxide)-based dissolving pulp was investigated. The NMMO-based dissolving pulp was usually used for the manufacture of high quality fabrics, and need to have high alpha cellulose content and high brightness. NMMO, which is environmentally friendly, and reusable after recovering process, is very sensitive to the metal ions such as Cu, Fe, Mg, and Cr. Electron beam, sulfuric acid, acetic acid, and ozone treatment before bleaching were used and the concentration changes of the metal ions were compared to that of EDTA, a chelating agent. It was found that both acid treatments (sulfuric and acetic acid) were very effective and comparable to EDTA treatment at the same dosage in metal ion reduction, but electron beam and ozone treatment were not. The sulfuric acid treatment turned out to be effective in metal ion reduction, and most inexpensive.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.157-167
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• 2011

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.4
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• pp.8-16
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• 2003

The objective of this study was to investigate the potential application of the separated refining system in the papermaking process using cotton pulps. The cotton staple and linter fibers were expected to show a great difference in their refining responses due to their morphological and physical differences. Experiments were conducted to examine the differences in flocculation tendency, CED viscosity, fiber length, handsheet properties and the SEM surface images between staple and linter fibers at a given refining degree. These fibers were also subjected to separated refining in a laboratory-scale beater and in a mill-scale refiner as well. The effect of the separated refining on the refining rates and papermaking properties were evaluated. Results obtained are summarized as follows: 1. Fiber flocculation tendency of cotton staple was estimated to be significantly greater than that of linter fibers; 2. The staple fibers showed higher cellulose DP, longer fiber length and higher sheet strength at a given refining degree compared to linter fibers, but remarkably slower refining rate was observed; 3. The separated refining system exhibited a significant increase in sheet strengths, especiauy in folding endurance, with an increase in the fibrillation on the surface of staple fibers, but slightly lower or comparable fiber length after refining to the mixed refining system; 4. Similar results were also obtained from the machine trial in which about 7-8％ energy saving effects were achived in the separated refining system. On the basis of the results observed in this study, it was concluded that a significant increase in paper strength and a substantial reduction in refining energy consumption could be achieved using the separated refining system for the cotton staple and linter fiber stock refining.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.1
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• pp.1-10
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• 2011

To investigate the combination dyeing properties of natural dyes, the combination dyeing using gallnut,-Al, Cu, Fe-sappan wood, and gallnut-Al, Cu, Fe-gardenia was performed on bast fiber of mulberry, cotton, silk, and their K/S values, colors, and sunlight fastness were measured. The gallnut-Al, Cu, Fe-gardenia dyeing showed the highest K/S values when the dyeing concentration of gallnut is 3%. It tended to show the higher K/S values than gallnut-Al, Cu, Fe-sappan wood. The silk showed the highest values of in K/S, and then followed by cotton, and bast fiber of mulberry. The mordants developed different colors on the bast fiber and the cotton treated with gallnut-Al, Cu, Fe-sappan wood. However, the silk showed a series of YR, showing no effect of the mordants on the development of color. The combination dyeing of gallnut-Al, Cu, Fe-gardenia showed a series of Y. The results showed that sappan wood could develop various colors but gardenia could develop a series of Y. No distinct improvement on sunlight fastness of the combination dyeing was observed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.2
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• pp.68-74
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• 2016

Nanofibrillated cellulose (NFC) was prepared from cotton linter after electron beam irradiation to investigate its effects on the manufacturing efficiency of the NFC preparation and the property changes by the treatment. Mechanical device (Super Masscolloider) was used to prepare the NFC and its passing frequency for each NFC preparation was recorded. More electron beam irradiation resulted in less passing frequency. Alpha cellulose content, molecular weight, crystallinity index, and thermal decomposition behavior of each treatment were lowered by electron beam treatment (10 and 100 kGy) and grinding process. NFC films were prepared to investigate their mechanical properties. There were little changes in tensile properties of the NFC films.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.133-137
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• 1982

Radiography is one of the important tool adopted in daily dental practice and medical diagnosis. To visualize soft tissuechange various contrast media has Been introduced. Any cavity or space can be easily determined by increasing the X-ray absorption of the cavity using the radiopaque contrast media which widely employed in medical radiography to show much of the digestive, cardiovascular, pulmonary, and renal system. The essential part of any radiopaque medium is a heavy element that can absoarb most of the X-ray beam. The element must be noninjurious and easily eliminated. Both aqueous and oil suspensions of iodine containing compounds' are available to the dental profession, for example Lipiodol and Dionosil. The study was designed to determine toxic effect of Lipiodol to the vital pulp and to confirm visualization ioprovement in pulp canal. 1. Thin mixture of Calcium hydroxide and Lipiodol was applied to 19 deep vital cavities for 24 hours. Only one case complained slight pain for short time. 2. Cotton pellet over-saturated in Lipiodol was inserted in coronal chamber of which 6 were non vital and 5 were vital. The transference of Lipiodol was not noticed in every case after 24 hours. 5 cases with vital pulp tissue in the canals showed no clinical symptome. 3. Extracted 20 teeth were routinely prepared for endodontic treatment and applied Lipiodol in conjunction with cotton fiber as deep as midportion of the roots. After 24, hours the medicament reached to nearly the end of apex, but there were no evidence of penetration in dentine layer and migrate into ramified canal.

• Journal of Practical Agriculture & Fisheries Research
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• v.11 no.1
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• pp.159-171
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• 2009

Required total substrates amounts for mushroom production are 212,186M/T in Korea. 80% of these total substrates amounts, 169,748 M/T is used for main substrates. Also 20%of these total substrates amounts, 42,438 M/T is used for additives. Main substrates 169,748 M/T is composed of sawdust, waste cotton, cotton seed hull, straw and com cob etc.. Additives 42,438 M/T is composed of rice bran, wheat bran and beet pulp etc. In the mushroom management, the cost of substrates purchase is composed for the most of management. Substrates amount is limited to supply, and the demand of mushroom substrates is on the increase continuously. So there is nothing but the cost of substrates are raising. Therefore the most important thing must develop the cheap substrates for the mushroom production.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.317-325
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• 2011