• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.63-66
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• 2003

최근 미래를 선도해 갈 것으로 인정받는 최첨단 기술로서 나노기술(NT), 바이오기술(BT), 정보기술(IT)이 있다. 나노기술은 원자나 분자 정도로 미세한 크기의 물질을 다루는 기술로 형태학적인 특성에 기인한 물리적 및 화학적인 장점을 활용한 연구가 활발히 이루어지고 있다. 나노섬유는 현재 섬유 관련 분야에서 가장 많은 연구가 이루어지고 있는 주제로 섬유의 직경이 수십 nm ~ 수 $\mu\textrm{m}$ 수준인 섬유를 말한다. (중략)

• Polymer(Korea)
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• v.34 no.6
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• pp.522-526
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• 2010

Bacterial cellulose is produced by the bacterium Gluconacetobacter xylinus, which forms a nanofibrous pellicle in its culture medium. We studied properties of the bacterial cellulose such as crystallinity, viscosity, morphology, and mechanical properties according to the carbon source. Static cultures of Gluconacetobacter sp. V6 were performed in three kinds of media: standard Hestrin-Schramm medium, and modified medium with either glycerol or molasses as carbon sources. Cell growth and cellulose yield were increased in the glycerol and molasses media. The culture in the glycerol medium improved the physical properties of cellulose such as crystallinity, intrinsic viscosity, and breaking stress. However, the culture in the molasses medium decreased crystallinity, crystallite size, and intrinsic viscosity of cellulose. In summary, the cellulose yield was remarkably improved in the molasses medium, but with inferior structural properties.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.302-309
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• 2013

The highly porous cellulosic aerogels were prepared by freeze-drying method using sodium hydroxide-urea aqueous solution in the process of dissolution, gelation, regeneration and organic solvent substitution. The structural characteristics of porous aerogel were analyzed using scanning electron microscopy and nitrogen adsorption apparatus. As a result, the dissolving pulp was completely dissolved, but filter papers and holocellulose were divided into two layers (dissolved and undissolved parts) in the process of centrifugation. The structure of aerogel from dissolved pulp showed porous pores in the surface and net-shaped network in the inner part. Aerogels from filter paper and holocellulose had the condensed porous network surface and the open-pore nano-fibril network inner structure. Undissolved form of fibers was observed in the aqueous solution of aerogel from holocellulose. The BET value ($S_{BET}$) of aerogel from dissolved pulp was ranged in 260~326 $m^2/g$, and it was decreased with the increase of concentration. Whereas, the $S_{BET}$ value of aerogel from filter paper (198~418 $m^2/g$) was increased with the increase of concentration. The $S_{BET}$ value of aerogel from holocellulose were 137 $m^2/g$ at 2% (w/w) of cellulose, and it was increased to maximum 401 $m^2/g$ at 4% (w/w) of cellulose. Then, it was decreased at 5% (w/w) of cellulose.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.268-277
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• 2017

In this study, lignocellulose nanofibrils (LCNFs) were prepared from Pussy willow wood powder by disk-milling after pretreatment using the cosolvent of 1-ethyl-3-methylimidazolium acetate ([EMIM]Ac) and N,N-dimethylformamide (DMF) with different mixing ratios for different time. All pretreated samples showed native cellulose I polymorph and cellulose crystallinity was lowest when cosolvent of DMF with 30% [EMIM]Ac was used. Average crystallite size of raw material and the pretreated product by MDF and its cosolvent with 10% [EMIM]Ac was found to be about 3.2 nm and decreased with increasing pretreatment time at the DMF cosolvent with 30% [EMIM]Ac. Defibrillation efficiency was improved by loosening wood cell wall structure by the pretreatment using co-solvent system of [EMIM]Ac and DMF.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.3
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• pp.175-181
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• 2008

Cellolose nanoparticles loaded with retinyl palmitate were prepared by modified spontaneous emulsification solvent diffusion method. We used polysorbate 20, polysorbate 60, and PPG-26-Buteth-26/PEG-40 Hydrogenated castor oil as dispersion medium. The optimum condition for particle size of cellulose nanoparticles was 1w/v% ethyl cellulose with, 3w/v% polysorbate 60 solution. And The optimum condition for leading amount of retinyl palmitate of cellulose nanoparticles was 2w/v% ethyl cellulose with 1w/v% polysorbate 60 solution. Also, we found that this optimum condition can be applicable to other active compounds.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.30 no.1
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• pp.1-14
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• 2024

As awareness of environmental issues continues to grow, there is an escalating demand for recycling and repurposing byproducts of agricultural and food production processes and their conversion to high-value products. Coffee is the most widely consumed beverage globally; during coffee beverage processing and consumption, byproducts such as coffee silverskin (CS), spent coffee grounds (SCGs), and oil are generated. Despite containing beneficial materials such as cellulose, hemicellulose, lignin, lipids, and bioactive substances, these byproducts are typically discarded in landfills or incinerated. The utilization of CS, SCGs, and oil in the development of packaging materials holds significant potentials toward the realization of a sustainable society. To this end, considerable research efforts have been dedicated to the development of high-value materials derived from coffee byproducts, including functional fillers, polymer composites, and biodegradable polymers. Notably, CS and SCGs have been employed as functional fillers in polymer composites. Additionally, lipids extracted from SCGs have been used as plasticizers for polymers and cultured with microorganisms to produce biodegradable polymers. This review focuses on the research and development of polymer/CS and polymer/SCG composites as well as cellulose extraction and utilization from CS and SCGs and its applications, oil extraction from SCGs, and cultivation with microorganisms using extracted oil for polyhydroxyalkanoates(PHA) production.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.11-12
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.17-18
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1553-1554
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• 2013

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.812-813
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• 2013