• 한국응용과학기술학회지
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• 제15권3호
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• pp.39-45
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• 1998

In recent years, there has been considerable interest in the development of new functional surfactant including new type of anionic surfactants. Anionic surfactants, ${\alpha}-sulfo$ fatty acids that straight long chain alkyl group having from 12 to 18 carbon atoms, were synthesized with sulfur trioxide-dioxane complex to good yield. Xylitol ${\alpha}-sulfo$ fatty acid esters were obtained by reaction that the acetification and esterification of xylitol, by addition reaction with sodium chloride and hydrolysis respectively. These compounds were a new group of destructible surfactants which readily hydrolyzed and oxidized in natural water reservoirs. Physical properties of these new compounds involved surface tension, critical micelle concentration(cmc), foaming power, emulsion power, and hydrolysis properties, were measured. The cmc values of the compounds by ring method were assumed to $7.0{\times}10^{-3}{\sim}3.0{\times}10^{-2}mol/{\ell}$ range and surface tensions at cmc were $25{\sim}31dyne/cm$ respectively.

• Fibers and Polymers
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• 제6권3호
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• pp.200-205
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• 2005

Celite powder surface-modified with cationic surfactant was used to make polyethylene (PE) specialty film that can be contrasted with ordinary film in having high odor storing capacity and long odor lasting period. Mechanical properties of the films were sacrificed as more celite particles were included, whether celite surface was modified or not. The film with CTAS-modified celite showed the best odor storing and lasting properties for five different flavors of odor, three artificial and two natural ones, among the kinds of films developed. Comparisons among the different films are made, together with brief discussion about the reason for differences in odor lasting period and possible application to packaging industry.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.15-18
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• 2001

Sorption/desorption studies were conducted to determine sorption/desorption characteristics of phenolic compounds (phenol and 4-chlorophenol) in organically modified natural bentonite. The cationic exchange capacity (CEC) of bentonite was exchanged with a cationic surfactant, hexadecyltrimethylammonium (HDTMA), to enhance the removal capacity of organic phenol contaminants dissolved in aqueous solution. This modification produces a change of the surface property of bentonite from hydrophilic to organophilic. The single-solute and bi-solute competitive adsorptions were performed In batch mode to investigate the removal of two toxic organic Phenols, chlorophenol and 4-chlorophenol on the HDTMA-bentonite. The adsorption affinity of the 4-chlorophenol was higher than phenol due to higher octanol:water partition coefficient (Kow). The single-solute and bi-solute competitive desorptions were also performed investigate the competitive desorption of the phenolic compounds from HDTMA-bentonite. Freundlich model was used to analyze the single-solute adsorption/desorption results, while the IAST model predicted the hi-solute adsorption/desorption equilibria. The IAST model well predicted hi-solute competitive adsorption/desorption behaviors.

• 한국식품과학회지
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• 제13권1호
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• pp.74-89
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• 1981

Breadmaking is a complex system in which many variables govern the production of acceptable bread. Lipids, a minor component of wheat flour, function importantly in bread-making. Shortening, or fat, is one of the essential ingredients in commercial baking. Beneficial shortening effect depends on type and quantity of lipids present in wheat flour and also on wheat flour quality. Surfactants have been used in baking industry during last decade because certrain surfactants can replace shortening and/or natural flour lipids. A proper combination of lipidshortening-surfactant is more useful in the production of specialty breads such as whole wheat breads, high protein breads, high fiber breads or even non-wheat composite breads rather than in the production of regular white breads. This presentation is a review of recent studies on the contribution of flour lipids, shortening, and surfactants, alone or in combination in the production of breads; illustrations are mainly from data obtained in the author's laboratory.

• 통합자연과학논문집
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• 제1권2호
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• pp.76-78
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• 2008

A series of the long-chain iron(II) alkylsulfonate hydrates were synthesized via self-assembly of surfactant alkyl chains in aqueous medium. Reaction of iron(II) salts with n-alkylsulfonate yields lamellar $Fe(CnH2n+1SO3)2{\cdot}4H_2O$. These compounds show a layered structure, as determined by XRD, consisting of alternating organic alkylsulfonate layers and inorganic iron(II) hydrate layers, with interlayer distances of upto 3.2 nm. This lamellar structure may be attributed to the amphiphilic nature of the surfactants, mediating the coordination and H-bionding interactions, and the hydrophobic alkyl chains. An alkyl chain packing of present system are differ from those of similar Cu(II) series, which are attributed from the size of hydrated metal(II) ions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.31-32
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• 2007

Oil-based nanofluids are prepared by dispersing spherical and fiber-shaped $Al_2O_3$ and AlN nanoparticles in transformer oil. Two hydrophobic surface modification processes are compared in this investigation. It is obvious that the combination of nanoparticle, surfactant and surface modification process is very important for the dispersity of nanofluids. For ($Al_2O_3$+AIN) particles with 1% volume fraction, the enhancement of thermal conductivity and convective heat transfer coefficient is nearly 11% and 30%, respectively, compared to pure transformer oil. The cooling effect of ($Al_2O_3$+AlN)-oil nanofluids on the heating element and oil itself is confirmed by a natural convection test using a prototype transformer.

• 대한화장품학회지
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• 제49권3호
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• pp.231-245
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• 2023

화장품 업계에서는 미백, 주름, 항산화, 항노화 등 기능성 화장품의 신소재 개발과 더불어 실제로 피부에 적용 시 피부흡수율을 높이는 기술이 중요하다. 이에 본 연구에서는 실험설계법인 반응표면분석법(RSM)을 활용하여 나노에멀젼 제형을 최적화하고자 하였다. Glabridin을 활성성분으로 하여 고압유화 방법으로 나노에멀젼을 제조하였으며, 최종적으로 최적화한 나노에멀젼의 피부흡수율을 평가하였다. RSM 인자로서 계면활성제 함량, 콜레스테롤 함량, 오일 함량, 폴리올 함량, 고압유화 압력, 고압유화 횟수를 달리하여 나노에멀젼을 제조하였다. 그 중 입자 크기에 가장 큰 영향을 미치는 인자인 계면활성제 함량, 오일 함량, 고압유화 압력, 고압유화 횟수를 독립변수로 하였고, 나노에멀젼의 입자 크기와 피부흡수율을 반응변수로 하였다. 중심점 5 회 반복실험을 포함하여 총 29 회 실험이 무작위로 수행되었으며, 제조된 나노에멀젼의 입자 크기와 피부흡수율을 측정하였다. 그 결과를 바탕으로 최소 입자 크기, 최대 피부흡수율을 갖는 제형을 최적화하였으며, 계면활성제 함량 5.0 wt%. 오일 함량 2.0 wt%, 고압유화 압력 1,000 bar, 고압유화 횟수 4 pass를 최적 조건으로 도출하였다. 최적 조건으로 제조한 나노에멀젼의 물성으로 입자 크기는 111.6 ± 0.2 nm, 다분산지수는 0.247 ± 0.014, 제타전위는 -56.7 ± 1.2 mV로 측정되었다. 나노에멀젼과 일반 에멀젼 피부흡수 시험 결과, 24 h 후 나노에멀젼의 누적 투과량은 79.53 ± 0.23%이며, 대조군으로서 에멀젼의 누적 투과량은 66.54 ± 1.45%로 나노에멀젼이 에멀젼보다 13% 높았다.

• 한국환경과학회지
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• 제20권2호
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• pp.185-197
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• 2011

Sorption of chlorinated pesticides such as 2,4-dichlorophenoxyacetic acid (2,4-D) and atrazine onto natural clays (montmorillonite and zeolite) modified with cationic surfactant, hexadecyltrimethyl-ammonium (HDTMA) and a natural soil was investigated using batch adsorbers. The clays were transformed from hydrophilic to hydrophobic by the cation exchange between clay surface and HDTMA up to 100% of the cation exchange capacity (CEC). Physicochemical characteristics of the sorbents such as pH, PZC (point of zero charge), organic carbon content ($f_{oc}$), fourier transform infrared spectroscopy (FT-IR), differential thermogravimetric analysis (DTGA) and X-ray diffraction (XRD) were analyzed. Sorption isotherm models such as Freundlich and Langmuir were fitted to the experimental data, resulting Langmuir model ($R^2$ > 0.986) was fitted better than Freundlich model ($R^2$ > 0.973). Sorption capacity ($Q^0$) for 2,4-D and atrazine was in the order of HDTMA-montmorillonite > HDTMA-zeolite > natural soil corresponding to the increase in organic carbon content ($f_{oc}$). The sorption of the pesticides was also affected by pH. The sorption of 2,4-D decreased with the increase in pH, whereas that of atrazine was not changed. This indicated that the sorption capacity ($Q^0$) of 2,4-D and atrazine was not affected by the solution pH because they exist as anionic (deprotonated) forms at pH above pKa. The results indicate that organoclay has a promising potential to reduce chlorinated pesticides in the effluent from golf courses.

• 생명과학회지
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• 제23권4호
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• pp.501-509
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• 2013

포름알데히드는 주로 산업용으로 사용되는 독성이 강한 물질로서 생체에 노출 시 염증, 산화적 스트레스, 알레르기 반응, 나아가서 암을 유발하게 된다. 불가사리에서 추출되는 saponin은 sulphated sterol glycosides 등으로서 인삼 saponin (ginsenoside)들과 화학적 구조가 비슷하여 항균 및 세포독성을 비롯한 미생물을 괴사시키는 기능을 가지고 있음이 보고되었다. 또한 손상된 불가사리의 조직에는 염증성 사이토카인이 발현되는데 TGF-${\beta}$의 증가로 손상 받은 부위를 빠르게 치료, 재생하게 된다. 본 실험은 조직손상 후 8일 된 불가사리 추출물과 포름알데히드를 IMR-90에 처리했을 때와 포름알데히드에 노출시킨 ICR 마우스에 불가사리 추출물을 흡입시켰을 때 염증성 폐 손상의 방어 및 치료에 미치는 효과를 알아보았다. 포름알데히드에 노출된 IMR-90에 조직손상 후 8일이 경과한 불가사리 추출물을 처리한 결과, 세포의 유의한 증식을 보였으며 염증 조절에 영향을 주는 TNF-${\alpha}$, NF-${\kappa}B$의 발현억제 및 $I{\kappa}-B{\alpha}$의 합성을 촉진시켰다. 포름알데히드에 노출된 ICR 마우스에 조직손상 후 8일이 경과한 불가사리 추출물을 처리한 군에서 체중의 증가, 항산화 효소의 증가, 지질과산화 작용의 감소, surfactant protein A의 증가, TNF-${\alpha}$ 및 NF-${\kappa}B$의 발현억제, $I{\kappa}-B{\alpha}$ 발현의 증가와 조직재생에 우수한 효과를 보였다. 이러한 결과는 포름알데히드로 인한 세포 및 폐 손상을 불가사리 추출물의 항염증 작용을 통하여 억제하거나 완화시킴을 확인할 수 있다.

• Journal of Microbiology and Biotechnology
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• 제10권3호
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• pp.349-354
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• 2000

Abstract A facultative alkalophilic gram-negative Vibrio metschnikovii strain RH530, isolated from the wastewater, produced several alkaline proteases (VAP) including six alkaline serine proteases and a metalloprotease. From this strain, high yielding YAP mutants were isolated by NTG treatment. The isolated mutant KS1 showed nine times more activity than the wild-type after optimization of the culture media. The production was regulated by catabolite repression when glucose was added to the medium. The effects of several organic nitrogen sources on the production of the YAP were investigated to avoid catabolite repression. The combination of 4% wheat gluten meal (WGM), 1.5% cotton seed flour (eSF), and 5% soybean meal (SBM) resulted in the best production when supplemented with 1% NaCl. The YAP showed a resistance to surfactants such as $sodium-{\alpha}-olefin$ sulfonate (AOS), polyoxy ethylene oxide (POE), and sodium dodecyl sulfate (SDS), yet not to linear alkylbenzene sulfonate (LAS). However, the activity of the YAP was restored completely when incubated with LAS in the presence of POE or $Na_2SO_4$. The YAP was stable in a liquid laundry detergent containing 6.6% SLES (sodium lauryl ether sulfate), 6.6% LAS, 19.8% POE, and stabilizing agents for more than two weeks at $40^{\circ}C$, but the stability was sharply decreased even after 1 day when incubated at $60^{\circ}C$. A washing performance test with the YAP exhibited it to be a good washing power by showing 51 % and 60% activity at $25^{\circ}C{\;}and{\;}40^{\circ}C$, respectively, thereby indicating that the YAP also has a good detergency at a low temperature. All the results suggest that the YAP produced from the mutant strain KSI has suitable properties for use in laundry detergents.rgents.