• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.43-48
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• 2018

An etchant capable of forming a circuit in an FTO film that can replace ITO, which depends on full imports, was prepared. The etching solution is composed of 1 to 30% by weight of fluoride, 1 to 20% by weight of acid, 0.5 to 5% by weight of surfactant, 5 to 20% by weight of solvent, 0.5 to 10% by weight of corrosion inhibitor and the balance of water. This etchant can be etched using a dry film, thereby reducing the cost, and is free from bubbles and residue of the etchant. The characteristics of the etchant were etched in a time of 2 minute with a 100 nm thick FTO, and the etchant temperature was maintained at $50^{\circ}C$. An undercut of -0.00364% was obtained when put into a 2 minute etching solution. No harmful substances such as Cd, Pb, Hg and Cr components were measured. The use of FTO in Korea where rare earths do not exist can achieve localization and import substitution effect.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.684-689
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• 2012

Poly(acrylic acid) (PAA) microspheres is one of the widely-used polymeric materials for the bio-field application and the electric materials. For the synthesis of PAA microspheres, the polymerization technique using surfactants is applied. After the synthesis, the purification and separation processes are required for the removal of surfactant. When general organic solvents were used, many problems, such as huge amount of waste solvent, additional separation processes, and the possibility of residual media, were occurred. Thus, High-pressure Soxhlet extraction using liquid $CO_2$ was developed to solve these problems. In this study, High-pressure Soxhlet extraction of the synthesized PAA microspheres using liquid $CO_2$ was conducted for the removal of Monasil PCA which is used for the dispersion polymerization of acrylic acid in compressed liquid Dimethyl ether (DME). The morphology of the extracted PAA particles was checked by field emission scanning electron microscopy (FE-SEM) and the residual concentration of Monasil PCA was analyzed by inductively coupled plasma - Optical Emission Spectrometer (ICP-OES). For studying the effect of the solvent effect, Soxhlet extraction was conducted using n-hexane, liquid DME, and liquid $CO_2$. In case of n-hexane, some extracted PAA microspheres were produced. However, deformation was also occurred due to the high thermal energy of n-hexane vapor. Liquid DME could not remove Monasil PCA. When using liquid $CO_2$, the extracted PAA microspheres which were free for the residual solvent were produced without deformation. For finding the optimum operating condition, high-pressure Soxhlet extraction was conducted for 8 hours with changing the temperature of reboiler and condenser. When the extractor temperature is $19.6{\pm}0.2^{\circ}C$ and the pressure is $51.5{\pm}0.5$ bar, the best removal efficiency was obtained.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.560-566
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• 1998

Background: Bovine pericardial bioprosthesis treated with glutaraldehyde (GA) is one of the most popular prosthetic materials, but late calcific degeneration after implantation is a problem that remains unsolved. For the purpose of mitigating the calcific degeneration, we added MgCl2 into the 0.625% GA solution to compete with calcium for binding to the free aldehyde from GA and pretreated with the surfactants like sodium dodecyl sulfate (SDS) and Triton X-100 before GA fixation for preventing the phospholipid infiltration into the pericardial tissue, the first step of the calcific degeneration. Material and Method: 40 square-shaped pieces of bovine pericardia were fixed in 0.625% GA solution with 4g/L MgCl2 6H2O as a control group (group 1). 40 pieces pretreated with 1% SDS were also fixed in the same GA solution (group 2) and other 40 pieces pretreated with 1% Triton X-100 were prepared with the same method (group 3). After 1 month of fixation these were implanted into the belly of 40 Sprague-Dawley subdermally and extracted 1 month, 2 months, 3 months and 6 months after implantation. With atomic absorption spectrophotometry we measured the deposited calcium amount. Result: 1 month after implantation we could not find any differences between the three groups, but by the 2nd month calcium deposition was 0.921$\pm$0.121 mg/g in group 1, 0.481$\pm$0.037 mg/g in group 2 and 1.369$\pm$0.200 mg/g in group 3. By the 3rd month it was 0.786$\pm$0.080 mg/g in group 1, 0.584$\pm$0.054 mg/g in group 2 and 1.139$\pm$0.188 mg/g in group 3, and on the 6th month 1.623$\pm$0.601 mg/g in group 1,0.501$\pm$0.043 mg/g in group 2 and 1.625$\pm$0.382 mg/g in group 3, with statistical significance in group 2(p<0.05). Conclusion: Pretreatment with SDS showed meaningful calcium mitigation effects on subcutaneously implanted bovine pericardium in the rat models but the neutral type surfactant, Triton X-100, had no positive mitigation effect in this experiment.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.106.2-106.2
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• 2010

동식물성 기름과 메탄올의 전이에스테르화 반응에 의해 생산되는 바이오디젤은 환경친화성과 지속가능성이 인정됨에 따라 그 생산량이 급격히 증가하고 있어 대두유, 유채유, 팜유 등의 원료유 부족과 가격 상승, 수급 불안정 등의 문제가 대두되고 있다. 이를 해결하기 위한 방안으로 유리지방산 함량이 높은 저가유지 자원(폐식용유, 폐돈지, 폐우지, soapstock, trapped grease)과 새로운 오일 작물을 이용한 생산 기술 연구가 활발히 진행되고 있다. 본 연구에서는 비활용 해외 열대작물 씨앗에서 착유한 식물성 오일을 정제하여 바이오디젤 원료유를 생산하는 과정에서 발생하는 폐기물(폐유, 폐수)의 경제적 처리 방안으로 유화유 제조 원료(벙커C유, 물)와 유화유 제조 첨가제(무기계, 유기계)로 활용 가능성을 검토하였다. 열대작물 오일의 물성 분석 결과 고형물, 수분, 인지질(phospholipid), 유리지방산(free fatty acid) 함량이 기존 원료유보다 매우 높게 나타났다. 인지질은 바이오디젤 제조 반응후 에스테르와 글리세린의 층분리를 방해하고 유리지방산은 염기촉매와 결합하여 지방산염을 생성해 생산 수율을 감소시킨다. 고형물과 수분 역시 촉매반응에 악영향을 가지나 여과와 감압증발에 의해 쉽게 제거가 가능하다. 유리지방산은 산촉매 에스테르화 반응에 의해 제거가 가능하다. 인지질은 탈검(degumming) 과정을 통해 제거하며 탈검은 수용성 탈검, 산 탈검, 세정 공정으로 구성된다. 착유한 원료유의 고형물을 제거 후 물과 수세하여 수용성 인지질을 수화하여 층 분리해 제거하고 상층의 오일은 추가적인 산 탈검을 수행한다. 그 뒤 세정을 통해 사용된 탈검제인 산과 추가적으로 수화된 인지질을 제거하게 된다. 이러한 3단계의 탈검 과정에서 하층으로 오일과 물이 폐기물로서 배출되며 본 연구에서는 배출 폐기물을 다시 층분리하여 오일층과 물 층으로 구분하여 유화유 제조에 사용되는 벙커C유, 물, 그리고 기존 유기계 및 무기계 유화제의 대체 가능성을 조사하였다. 유화 연료유는 기름과 물을 균일한 분산상으로 혼합한 연료유로 연소시 오일계 성분의 미연분을 감소시켜 연료 효율 제고와 배출가스 성상을 개선하기 위해 개발되어 왔다. 본 발표에서는 다양한 종류의 상용 첨가제 및 바이오디젤 원료유 생산 폐기물을 활용해 유화 연료유를 제조하였으며 각 유화유의 장시간의 상(phase) 안정성을 비교하였다. 바이오 폐기물 중에는 천연 계면활성제(surfactant)인 인지질이 다량 함유되어 있어 기존의 무기계 및 유기계 유화제보다 상 안정성이 우수하게 나타났으며 바이오디젤 원료유 생산 공정의 폐기물인 폐유과 폐수의 활용이 가능한 것으로 나타났다.

• Analytical Science and Technology
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• v.10 no.2
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• pp.126-130
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• 1997

Electrochemical behavior of 1.0mM bis(2,2'-bipyridyl)copper( II )(${Cu(bpy)_2}^{2+}$) in 100mM NaCl+27mM $MgCl_2$ solution with and without sodium dodecyl sulfate(SDS) is investigated. In the presence of SDS, $E_{pa}$ and $E_{1/2}$ of ${Cu(bpy)_2}^{2+/1+}$ shifts to the positive direction compared to the SDS free. Teh intersection of two lines on ${\Delta}E_p$ vs. -log[SDS] plot for 1.0mM $Cu(bpy)_2(NO_3)_2$ in 100mM NaCl+27mM $MgCl_2$ solution is a critical micelle concentration(CMC). Reduced form ${Cu(bpy)_2}^{1+}$ in the presence of $MgCl_2$ is more easily associated to dodecyl sulfate anion($DS^-$) than oxidized ${Cu(bpy)_2}^{2+}$. As the ionic strength is increased by the addition of multiply charged cations($MgCl_2$), the double layer becomes more compact and micelle formation is more difficult.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.104-115
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• 2003

A series of experiments was carried out to determine the possibility for the non-ionic surfactant (NIS) as a feed additive for ruminant animals. The effect of the NIS on (1) the enzyme distribution in the rumen fluids of Hereford bulls, (2) the growth of pure culture of rumen bacteria and (3) rumen anaerobic fungi, (4) the ruminal fermentation characteristics of Korean native cattle (Hanwoo), and (5) the performances of Holstein dairy cows were investigated. When NIS was added to rumen fluid at the level of 0.05 and 0.1% (v/v), the total and specific activities of cell-free enzymes were significantly (p<0.01) increased, but those of cell-bound enzymes were slightly decreased, but not statistically significant. The growth rates of ruminal noncellulolytic species (Ruminobacter amylophilus, Megasphaera elsdenii, Prevotella ruminicola and Selenomonas ruminantium) were significantly (p<0.01) increased by the addition of NIS at both concentrations tested. However, the growth rate of ruminal cellulolytic bacteria (Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefaciens and Butyrivibrio fibrisolvens) were slightly increased or not affected by the NIS. In general, NIS appears to effect Gram-negative bacteria more than Gram-positive bacteria; and non-cellulolytic bacteria more than cellulolytic bacteria. The growth rates of ruminal monocentric fungi (Neocallimastix patriciarum and Piromyces communis) and polycentric fungi (Orpinomyces joyonii and Anaeromyces mucronatus) were also significantly (p<0.01) increased by the addition of NIS at all concentrations tested. When NIS was administrated to the rumen of Hanwoo, Total VFA and ammonia-N concentrations, the microbial cell growth rate, CMCase and xylanase activities in the rumen increased with statistical difference (p<0.01), but NIS administration did not affect at the time of 0 and 9 h post-feeding. Addition of NIS to TMR resulted in increased TMR intake and increased milk production by Holstein cows and decreased body condition scores. The NEFA and corticoid concentrations in the blood were lowered by the addition of NIS. These results indicated that the addition of NIS may greatly stimulate the release of some kinds of enzymes from microbial cells, and stimulate the growth rates of a range of anaerobic ruminal microorganisms, and also stimulate the rumen fermentation characteristics and animal performances. Our data indicates potential uses of the NIS as a feed additive for ruminant animals.

• KSBB Journal
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• v.31 no.4
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• pp.277-283
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• 2016

In this system, rice cells were genetically modified to express human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) using RAmy3D promoter induced by sugar depletion. Even though the target protein fused with signal sequence peptide, plant cell wall can be a barrier against secretion of recombinant proteins. Therefore, hCTLA4Ig can be trapped inside cell wall or remained in intracellular space. In this study, to enhance the secretion of hCTLA4Ig from cytoplasm and cell walls into the medium, permeabilizing agents, such as dimethyl sulfoxide (DMSO), Triton X-100 and Tween 20, were applied in transgenic rice cell cultures. When 0.5% (v/v) of DMSO was added in sugar-free medium, intracellullar hCTLA4Ig was increased, on the other hand, the secreted extracellular hCTLA4Ig was lower than that of control. DMSO did not give permeable effects on transgenic rice cell cultures. And Triton X-100 was toxic to rice cells and also did not give enhancing permeability of cells. When 0.05% (v/v) Tween 20 was added in rice cell cultures, however, intracellular hCTLA4Ig was lower than that of control cultures. And the maximum 44.76 mg/L hCTLA4Ig was produced for 10 days after induction, which was 1.4-fold increase compared to that of control cultures. Especially, Tween 20 at 0.05% (v/v) showed the positive effect on the secretion of hCTLA4Ig though the decrease of intracellular hCTLA4Ig. Also, Tween 20 as a non-toxic surfactant did not affect the cell growth, cell viability and protease activity. In conclusion, secretion of hCTLA4Ig could be increased by enhancing permeability of cells regardless of the cell growth, cell viability and protease activity.

• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.595-601
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• 2014

The microstructures of NATM were examined by SEM, FT-IR spectra, tensile properties, mole % of [NCO/OH], and particle size analyzer. Growing concerns in the environment-friendly industries have led to the development of solvent-free formulations that can be cured. We had synthesized NATM(New Austria Tunnel Method) resin having the ability to protect stainless steel against corrosion. Comparing with general NATM resin and coatings, this resin that synthesized with polyurethane and epoxy was highly stronger in intensity and longer durability. Hybrid resin was composed of polyols, MDI, epoxy, silicone surfactant, catalyst and crosslink agent, and fillers. Moreover, fillers such as fume silica not only accelerated the curing rate but also improved the physical property as thermal barriers. The rigid segments of synthetic resin in mechanical properties were due to fume silica and the increase the mole% of [NCO/OH] for corrosion protection. In conclusion, the hybrid resin microstructure with crosslink agent and fume silica are good material for thermosetting coating of metal substrates such as stainless steel.

• Analytical Science and Technology
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• v.6 no.1
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• pp.1-8
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• 1993

The purpose of this study is to investigate the elution behavior of monosubstituted phenols and benzenes in micellar liquid chromatographic system, $C_{18}$ column-anionic surfactant, sodium dodecyl sulfate(SDS). The partition coefficients between the micellar pseudophase-water and modified stationary phase-water are calculated by the relationship between solute retention and micellar mobile phase(SDS) composition. The free energy of transfer of solute from water to micelle is also calculated from these values. There is a direct correlation between the hydrophobicity parameters in MLC and corresponding partition data for 1-octanol-water, which indicates that the hydrophobicity of molecules plays an important role in the partition for both systems and that quantitative structure activity relationships(QSAR) are available from studies on micellar partition. The other purpose of this study is to investigate methylene selectivity of alkyl homologous series through correlation between retention and the number of carbons. The correlation between hydrophobicity parameters in MLC and 1-octanol-water partition data was also observed when n-propanol was as a modifier in the mobile phase.

• Korean Journal of Microbiology
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• v.47 no.4
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• pp.356-363
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• 2011

The accidental releases of total petroleum hydrocarbons (TPH) due to oil spills frequently ended up with soil and ground water pollution. TPH may be degraded through physicochemical and biological processes in the environment but with relatively slow rates. In this study an attempt has been made to develop an integrated chemical and biological treatment technology in order to establish an efficient and environment-friendly restoration technology for the TPH contaminated soils. A Fenton-like reaction was employed as a preceding chemical treatment process and a bioaugmentation process utilizing a diesel fuel degrader consortium was subsequently applied as a biological treatment process. An efficient chemical removal of TPH from soils occurred when the surfactant OP-10S (0.05%) and oxidants ($FeSO_4$ 4%, and $H_2O_2$ 5%) were used. Bioaugmentation of the degrader consortium into the soil slurry led to an increase in their population density at least two orders of magnitude, indicating a good survival of the degradative populations in the contaminated soils ($10^8-10^9$ CFU/g slurry). TPH removal efficiencies for the Fenton-treated soils increased by at least 57% when the soils were subjected to bioaugmentation of the degradative consortium. However, relatively lower TPH treatment efficiencies (79-83%) have been observed in the soils treated with Fenton and the degraders as opposed to the control (95%) that was left with no treatment. This appeared to be due to the presence of free radicals and other oxidative products generated during the Fenton treatment which might inhibit their degradation activity. The findings in this study will contribute to development of efficient bioremediation treatment technologies for TPH-contaminated soils and sediments in the environment.