• 한국도로학회논문집
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• 제19권1호
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• pp.53-62
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• 2017

PURPOSES : This research was a fundamental study on the application of an integral $TiO_2$ solution to asphalt concrete pavement. The integral $TiO_2$ solution was produced in pilot production equipment; application of the integral $TiO_2$ solution to asphalt pavement was conducted to examine the pollution-reducing capability of photocatalytic compounds such as $TiO_2$. The photocatalytic $TiO_2$ reacted with air pollutants, converting them into small amounts of relatively benign molecules. METHODS : In this study, laboratory experiments were conducted using five various testing methods. Tensile strength ratio (TSR) and British pendulum test (BPT) were conducted in order to evaluate the properties of asphalt pavement subsequent to the integral $TiO_2$ solution coating. In addition, methylene blue testing, a measurement of nitrate on the coated pavement, and nitrogen oxide (NOx) reduction testing were conducted in order to evaluate photocatalytic reaction. Lastly, a UV-A lamp was used as a light source for photocatalytic reactions. RESULTS : Test results indicated no change in the properties of asphalt pavement following the integral $TiO_2$ solution coating. In order to evaluate the performance of asphalt pavement as a function of $TiO_2$, the moisture susceptibility and skid resistance were investigated. The moisture susceptibility and skid resistance satisfied there quirements related to pavement quality and safety specification. Furthermore, the effects of reduction of air pollution were significantly improved as determined via the methylene blue test and NOx reduction test. The $TiO_2$-paved asphalt specimen exhibited approximately 43% reduction of NOx. CONCLUSIONS : This study has suggested that applying $TiO_2$ rarely impacts asphalt pavement performance measures such as moisture susceptibility and skid resistance, and that its application may be a better means of reducing air pollution. Further studies, such as proper $TiO_2$ dosage rates and compatibility with various pavement types, are required to broaden and generalize its application.

• Natural Product Sciences
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• 제22권3호
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• pp.147-153
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• 2016

Inflammation plays an important role in host defense against external stimuli such as infection by pathogen, endotoxin or chemical exposure by the production of the inflammatory mediators that produced by macrophage. Anti-inflammatory factor is important to treat the dangers of chronic inflammation associated with chronic disease. This research aims to analyze the anti-inflammatory effects of Garcinia mangostana L. peel extract (GMPE), ${\alpha}$-mangostin, and ${\gamma}$-mangostin in LPS-induced murine macrophage cell line (RAW 264.7) by inhibiting the production of inflammatory mediators. The cytotoxic assay of G. mangostana L. extract, ${\alpha}$-mangostin, and ${\gamma}$-mangostin were performed by MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) to determine the safe and non-toxic concentration in RAW 264.7 for the further assay. The concentration of inflammatory mediators (COX-2, IL-6, and IL-$1{\beta}$) were measured by the ELISA-based assay and NO by the nitrate/nitrite colorimetric assay in treated LPS-induced RAW 264.7 cells. The inhibitory activity was determined by the reducing concentration of inflammatory mediators in treated LPS-induced RAW 264.7 over the untreated cells. This research revealed that GMPE, ${\alpha}$-mangostin, and ${\gamma}$-mangostin possess the anti-inflammatory effect by reducing COX-2, IL-6, IL-$1{\beta}$, and NO production in LPS-induces RAW 264.7 cells.

• 한국미생물·생명공학회지
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• 제47권4호
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• pp.630-638
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• 2019

아산화질소는 이산화탄소보다 약 310배 높은 지구온난화 지수를 갖는 주요 온실가스이다. 본 연구에서는 아산화질소 배출저감을 위해 고도처리슬러지를 접종원으로 이용하여 아산화질소 환원 컨소시움을 확보하였다. 이 컨소시움의 우점종은 Sulfurovum (17.95%), Geobacter (14.63%), Rectinema(11.45%)와 Chlorobium (8.24%)이었다. 아산화질소 환원 컨소시움의 활성에 미치는 C/N 비(mol·mol-1), 탄소원의 영향을 조사한 결과, C/N 비 6.3 및 아세트산을 탄소원으로 공급한 조건에서 최대 아산화질소 환원 활성을 나타냈다. 또한, 본 컨소시움의 3,000 ppm 이하의 아산화질소 농도 범위에서 아산화질소 농도가 증가할수록 환원속도도 증가하였다. 속도론적 해석 결과, 아산화질소 환원 컨소시움의 최대 아산화질소 환원 속도는 163.9 ㎍-N·g VSS^-1·h^-1이었다. 본 Consortium은 아산화질소를 N2로 환원하는데 관여를 nosZ 뿐만 아니라, 질산염을 아질산염으로 환원하는 narG, 아질산염을 일산화질소로 환원하는 nirK 유전자 및 일산화질소를 아산화질소를 환원하는 norB 유전자를 모두 보유하고 있었다. 이는 본 컨소시움은 아산화질소 제거 공정 뿐 만 아니라, 탈질공정에도 활용 가능한 유용한 미생물 자원임을 의미한다.

• 미생물학회지
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• 제39권3호
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• pp.175-180
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• 2003

Shewanella putrefaciens DK-1은 그람음성, 통성 혐기성 세균으로 $NO_{3}$, Fe(III), Mn(IV), humic acid와 같은 다양한 전자수용체를 이용한다. S. putrefaciens DK-1의 전자공여체의 이용능력은 제한적이며, lactate나 formate는 좋은 전자공여체로 이용되지만 acetate나 toluene은 이용하지 못하였다. 다양한 전자수용체간의 경쟁을 살펴보기 위해 전자수용체로 Fe(III)와 같이 $NO_{3}^{-}$, $NO_{2}^{-}$를 넣어 주었을 매 Fe(III)의 환원은 저해되었다. 또한 5. putrefaciens DK-1은 전자수용체로 토양에 광범위하게 존재하는 humic acid를 이용하였으며, 환원된 humic acid는 질산염에 의해서 다시 산화되었다. Fe(III) 환원능이 있는 환경 시료를 이용하여 탄소, 질소, 인과 같은 제한 요인이 Fe(III) 환원세균의 활성에 미치는 효과를 조사하였다. 천호지의 저질토와 대호의 농토에 각각 탄소원, 질소원, 인을 첨가해 주었을 경우 S. putrefaciens DK-1과 탄소원을 동시에 첨가해 주었을 때 가장 높은 철 환원능을 보여주었다.

• 한국입자에어로졸학회지
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• 제6권4호
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• pp.151-164
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• 2010

Inorganic ions and water are major components of ambient fine particles. Water content in fine particles is mainly determined by ambient meteorological conditions and the concentrations of hygroscopic species such as inorganic ions. Thus, to reduce fine particle mass concentration, it is important to accurately estimate the relationship between water content and the concentration of ions in fine particles. Water content in fine particles in Seoul are estimated by using a gas/particle equilibrium model to understand the characteristics of fine particle mass concentration. In addition, sensitivity of fine particle mass concentration to the changes of particulate ionic species (sulfate, nitrate, and ammonium) is estimated. It was found that water content in Seoul is mostly determined by the concentrations of the hygroscopic ionic species, especially, sulfate and ammonium, and ambient relative humidity.

• Preventive Nutrition and Food Science
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• 제17권4호
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• pp.306-309
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• 2012

This study was performed to investigate the potential use of Saussurea lappa C.B. Clarke as a source of antioxidant agents. Various solvent fractionates from S. lappa C.B. Clarke roots were investigated for their anti-oxidative effectiveness. The contents of total phenolics and flavonoids were determined by the Folin-Ciocalteu's colorimetric and the aluminum nitrate method, respectively. Total phenolic and flavonoid contents of n-butanol soluble fractionates from S. lappa C.B. Clarke, 44.43 ${\mu}g$ gallic acid equilibrium (GAE)/g extract and 92.15 ${\mu}g$ quercetin equilibrium (QE)/g extract, respectively, were higher than those of other solvent fractionates. The n-butanol soluble fractionates of S. lappa C.B. Clarke (1,000 ppm) showed the strongest inhibitory potential on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and reducing power at 92.98% and 0.38, respectively. Thus, our data shows that the S. lappa C.B. Clarke plant may help prevent antioxidative stress.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1277-1281
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• 2011

Making use of chitosan (CS) and ethylenediaminetetraacetic acid (EDTA) as a reaction system, CS-EDTA nanoparticles were synthesized through a facile counterion complex coacervation method. $Ag^+$ could enter porous CS nanoparticles synthesized with this method, allowing Ag nanoparticles within chitosan nanoparticles were synthesized by reducing silver nitrate with chitosan. Because of the noncovalent interaction between CS and EDTA, the EDTA could be easily removed via dialysis against water, and pure core/shell-type Ag/CS nanoparticles could be obtained. The nanoparticles showed higher antibacterial activity toward E. coli than the active precursor Ag nanoparticles and CS.

• 한국식품영양과학회지
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• 제11권2호
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• pp.31-35
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• 1982

폐액으로 방류되는 두부 폐수(whey)를 이용하여 alcohol 발효를 실시하였으며 다음과 같은 결과를 얻었다. whey중(中)에 함유(含有)된 환원당은 약 0.71%로서 이당(糖)을 이용(利用)하며 l당(當) 최대(最大) 1.86 g의 ethanol이 생산(生産)되었으나 수률(收率)이 낮아서 경제성은 희박하다. 그러나 발효에 의해서 단백질과 당이 각각 94%, 81%만큼이나 감소한 결과(結果)로 미루어 보아 두부 폐수중(廢水中)의 유기물(有機物)을 alcohol 발효(醱酵)에 이용(利用)할 수 있음을 확인(確認)하였다.

• 생물환경조절학회지
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• 제13권4호
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• pp.194-199
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• 2004

염류집적 토양에서 광합성균, Soil plus, 목초액, 활성탄 등 토양개량제가 오이와 토마토의 생육과 수량에 미치는 영향을 시험하였다. 그 결과 활성탄이 수량을 증진시키고 뿌리의 활력도 좋았다. 토마토 배꼽썩음병도 활성탄 처리구가 가장 낮았다. 토마토의 당도는 Soil plus구가 높았으며 질산염과 인산함량은 처리간에 차이가 없었다.

• 한국미생물·생명공학회지
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• 제14권6호
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• pp.467-471
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• 1986

Fusarium moniliforme으로부터 순모세포벽 분해효소를 생산하고 분리, 정제하여 효소특성 및 protoplast 제조실험을 하였다. Ammonium nitrate를 0.2％ 첨가한 Baker's yeast 배지에서 7일간 진탕배양으로 효소를 생산한 후 Ammonium sulfate로 분획하고 Sephadex(G-100) column chromatography하여 세개의 peak를 얻었다 첫 번째 peak는 proteolytic, lytic activity 및 laminarin 분해력가를 보였으며, 두 번째 Peak는 lytic activity와 laminarin 분해력가를 동시에 가지고 있었으며, 세 번째 peak는 lytic activity만을 가지고 있었다. 분리된 세개의 peak를 혼합하였을때 개개의 peak보다 훨씬 높은 역가을 나타내어 상승효과를 보였고 또한 환원제에 의한 효소력가의 상승효과도 있었다. protoplast 수율은 99.2％정도였다