• 대한환경공학회지
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• 제27권1호
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• pp.109-114
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• 2005

본 연구에서는 기상용 제오카본을 수처리에 적합하도록 염산으로 표면 개질 하였으며, 개질된 제오카본을 이용하여 단일 공정을 통한 암모니아성 질소와 질산성 질소 동시 제거 가능성을 평가하고자 하였다. 제오카본과 비교하여 표면 개질 제오카본의 강도가 62% 정도 증가하였으며, 암모니아성 질소와 질산성 질소 및 총질소 제거율이 약 2배 증가하였다. 또한 암모니아성 질소와 질산성 질소 제거 효율은 pH 및 온도 변화에 거의 영향을 받지 않았다. 따라서 수중에 존재하는 암모니아성 질소와 질산성 질소의 동시 제거가 매우 효과적으로 이루어질 수 있었으며, 본 연구 결과를 토대로 암모니아성 질소와 질산성 질소를 동시 제거할 수 있는 단일 공정 설계를 위한 기본 데이터 제시가 가능하였다.

• 고문화
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• 66호
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• pp.87-112
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• 2005

Stain removal on ivory has been, for a long time, considered an undesirable treatment in conservation field because ivory is hygroscopic and anisotropic, having different physical properties in different directions. Cyclododecane, which sublimes at room temperature, has been investigated for its use in conservation field since 1995, as a reversible temporary consolidant, sealing agent or coating, water repellent, and barrier layer. This research aims to remove stains on ivory, temporarily protecting the none-stained area or painted area from methanol, acetone or the aqueous cleaning system using cyclododecane as a hydrophobic sealing agent. This research also aims to obtain information regarding whether cyclododecane can be safely and effectively used on archaeological wet ivory. Melted cyclododecane and saturated solutions of cyclododecane in mineral spirits, and hexanes were applied to ivory samples. Application methods, working properties of cyclododecane on ivory, and effect of cyclododecane coating on moisture content of wet ivory were evaluated. The sealing layer formed by molten cyclododecane or by saturated cyclododecane solution in hexane or saturated cyclododecane solution in mineral spirits did not form a secure contact with the surface of the highly polished ivory. The sealing formed with two different layers, in which saturated cyclododecane solution in hexane was applied initially and then molten cyclododecane was applied over the first layer, was found to securely protect the painted area. When the wet samples were kept in 100% RH environments for a month, active mold growths were observed except in the samples sealed with molten cyclododecane. In conclusion, cyclododecane was an efficient hydrophobic sealing agent to protect painting area while cleaning stains on ivory. It also prevented mold growing on wet ivory and wet bone. Evenness of cyclododecane film on ivory will be determined in UV light. Analytical techniques will include visual observation, polarized light microscopy, Scanning Electron Microscope, and Gas Chromatography.

• 한국환경보건학회지
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• 제24권3호
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• pp.63-69
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• 1998

The treatment of soils and water contaminated with MTBE using the Fenton oxidation was investigated. The effects of dosage of $H_{2}O_{2}$, and Fe$^{2+}$ concentrations, and solution pH on transformation and mineralization in soil were evaluated. Generation of TBA and acetone following Fenton-oxidation of MTBE in water and generation of acetone following Fenton-oxidation of TBA were observed. Therefore TBA and acetone are degradation intermediates of MTBE. There was a large difference of treatment efficiency in Fenton oxidation of MTBE between soil and water system. This may be caused by the complex nature of soil, soil organic matter which can consumed OH $\cdot$ radicals, and interacting with inorganic-soil constituents. The pH of soil was observed to have a significant effect on the chemical oxidation efficient of MTBE in soil The data demonstrated that optimal pH range were pH 3~4 and around 6. The soil batch studies demonstrated that treatment efficiency of MTBE was enhanced by adding additional ferrous salts but Fenton-oxidation occurred in no additional iron which indicated that iron in soil can catalyze the Fenton-oxidation. The most effective parameter of Fentonoxidation was $H_{2}O_{2}$/Fe$^{2+}$ ratio which theocratical ratio is 0.5. The optimal range of this ratio was found to be 0.6~2.3. In evaluating effect of $H_{2}O_{2}$ dosage on treatment efficiency, the increase of $H_{2}O_{2}$ did not always lead to increase of decompositions of MTBE in soil. Fenton oxidation was effective in destroying MTBE in aqueous extracts of contaminated soil and water. Experimental data provided evidence that the Fenton oxidation can effectively remediate MTBE-contaminated water and soil.

• 자원환경지질
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• 제35권6호
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• pp.533-544
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• 2002

주요 및 미량원소들의 함량을 조절하는 반응들 동안 용존 원소들의 상대적인 유동성을 알아보기 기존에 발표된 강원도 지역 탄산수와 화강암에 대한 자료로부터 주·부·미량원소의 함량을 다시 살펴보았다. 탄산수내에 용존되어 있는 원소들의 상대적인 유동성은 Na으로 평균화한 탄산수-화강암간의 비로부터 계산하였다 계산결과는 탄산수 대수층내로 마그마에서 기원한 휘발성을 지닌 금속원소들의 가스에 의한 유입은 강원도 지역에서 무시할 만하며, 이런 유입은 상승하는 유체의 냉각에 의해 조절된다 이산화탄소가 유입된 약산성의 물에 의한 화강암의 용해반응이 금속원소들의 주요 공급원이다 유동성이 매우 낮은 원소 (Al)는 고체의 풍화산물 내에 우선적으로 잔류하는 반면, 알칼리 및 알칼리 토금속들과 OHA원소들 중 As과 U은 유동성이 있으며, 따라서 수용액계 내로 방출된다. 전이금속원소들은 중간정도의 유동특성을 보이는데, Fe와 Mn은 산화환원조건 또는 V, Zn과 Cu는 고체표면과 연관된 반응(흡착이나 침전)의해 주로 영향을 받는다.

• 한국염색가공학회지
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• 제29권4호
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• pp.247-255
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• 2017

Scutellaria Baicalensis(SB) is widely used in traditional and modern oriental medicine. It possesses several biology activities such as anti-oxidative, anti-inflammatory, antimicrobial and antiviral activities. In this study, a functional high density polyethylene (HDPE) fabric with antimicrobial properties was developed using zeolite microparticles as a SB extract delivery carrier. Zeolites loaded with SB extract were prepared by immersing in an SB extract aqueous solution. The average size of the SB extract-loaded zeolites was about 0.1 to $2.0{\mu}m$, and the morphology of the zeolites was not altered after SB extract binding. The resulting SB extract-loaded zeolites were then immobilized homogeneously onto the HDPE fabric using acrylic binder. The encapsulation efficiency of SB extract to the zeolite was more than 45%. The in vitro release test of SB extract-loaded zeolites containing HDPE fabrics showed release of 35% of the total SB extract by day 1 in a 24hours immersion study. Moreover, the SB extract-loaded zeolites containing HDPE fabrics showed effective antimicrobial activity against Streptococcus mutans, Staphylococcus aureus, and Klebsiella pneumoniae, indicating that this innovative delivery platform potently imparted antimicrobial activity to the HDPE fabric. In conclusion, the current study suggests that the HDPE fabric containing the SB extract-loaded zeolites microparticle carrier system has potential as an effective antimicrobial textile such as safety gloves, protective gloves etc.

• 대한기계학회논문집
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• 제14권1호
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• pp.241-250
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• 1990

본 연구에서는 낙구식 점도계를 이용하여 낮은 농도의 용액을 실험할 때 종말 속도측정의 어려움을 해결하기 위하여 레이저와 특수 타이머를 설치하였으며 정확한 특성시간을 결정하기 위하여 실린더 내부의 시험유체를 교란시키지 않고, 떨어뜨린 구 를 회수하는 장치를 제작하였다. 또한 주로 rheogoniometer에 의존하던 영 전단률 점성계수를 측정하기 위하여 속이 빈 알루미늄 구(hollow aluminium ball)의 밀도를 시험 유체와 거의 같은 정도까지 변화시켜가며 종말 속도를 측정하였으며 점탄성 유체 로써 Separan AP-273의 낮은 농도인 300에서 2000wppm까지의 저농도 용액에 대한 특성 시간을 여러모델에 의하여 실험적으로 결정하고 저농도 폴리머 용액에서 퇴화로 인한 점탄성유체의 특성 변화를 분석하였다.

• 한국자동차공학회논문집
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• 제18권5호
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• pp.85-90
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• 2010

As the environmental regulation of vehicle emission is strengthened, investigations for $NO_x$ and PM reduction strategies are popularly conducted. Two current available technologies for continuous $NO_x$ reduction onboard diesel vehicles are Selective Catalytic Reduction (SCR) using aqueous urea and lean $NO_x$ trap (LNT) catalysts. The experiments were conducted to investigate the $NO_x$ reduction performance of SCR system which can control the ratio of $NO/NO_2$, temperature and SV(space velocity), and the model gas was used which is similar to a diesel exhaust gas. The maximum reduction efficiency is indicated when the $NO:NO_2$ ratio is 1:1 and the SV is 30,000 $h^{-1}$ in $300^{\circ}C$. Generally, ammonia slip from SCR reactors are rooted to incomplete conversion of $NH_3$ over the SCR. In this research, slip was occurred in 6cases (except low SV and $NO:NO_2$ ratio is 1:1) after SCR. Among 6 case of slip occurrence, the maximum conversion efficiency is observed when SV is 60,000 $h^{-1}$ in $400^{\circ}C$.

• 분석과학
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• 제7권1호
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• pp.25-31
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• 1994

정지상과 이동상에 대하여 선택성의 차이가 크지 않은 알킬페놀류에 대한 2차 화학평형이론을 적용하여 분리도에 미치는 pH 영향을 연구하였다. 이동상으로는 물-아세토니트릴을 사용하였으며, pH는 탄산나트륨 완충 용액으로 조절하였다. 인접한 봉우리간의 선택성을 최대로 하는 pH 값은 $k^{\prime}_{HA}/k^{\prime}_{A-}$와 평균 해리상수값(${\Delta}pK$)으로부터 구하였으며, 이 방법에 의해 결정된 최적 pH는 11.18이었다. 선택성의 효과를 최대로 얻기 위하여 pH와 용매의 선택성을 동시에 고려하였다. 결정된 최적의 pH 조건하에서 메탄올, 아세토니트릴, 테트라히드로퓨란, 물의 4성분 혼합 용매 시스템을 이용하였고, 통계적인 심플렉스 방법인 overlapping resolution maps(ORM)을 사용하여 최적 용매 조성을 결정하였다. 이 방법에 의하여 결정된 최적 용매 조성비는 MeOH : ACN : THF = 14.4 : 81.8 : 2.8이었다.

• 한국식품과학회지
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• 제5권2호
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• pp.89-94
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• 1973

육제품(肉製品)의 착색제(着色劑)로 사용되고 있는 식용적색2호(食用赤色2號)와 황색4호(黃色4號)의 가열(加熱) 및 감마(線) 조사(照射)에 의한 변색정도(變色程度)와 첨가물(添加物)에 의한 영향을 model system 을 사용하여 관찰하였다. 황색2호(黃色2號)는 가열(加熱)에 의하여 뚜렷한 변색(變色)을 나타내지 않았으나 황색4호(黃色4號)는 Na-TPP 와 cinnamon oil 을 첨가(添加)하므로써 약간의 퇴색(褪色)을 하였다. 감마선(線) 조사(照射)에 의한 영향은 선량(線量)의 증가와 더불어 퇴색(褪色)하였으며 $NaNO_2$ 와 ascorbic acid 는 퇴색(褪色)을 억제하는 반면 Na-TPP 와 cinnamon oil 은 오히려 촉진하는 경향을 보였다. 이러한 퇴색도(褪色度)는 적색2호(赤色2號)보다는 황색4호(黃色4호(號)가 더욱 현저하였으며 $5^{\circ}C$ 보존(保存)보다는 $25^{\circ}C$보존(保存)에서 퇴색(褪色)이 촉진되었다.

• Biomolecules & Therapeutics
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• 제13권2호
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• pp.84-89
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• 2005

The purpose of this study was to characterize the putative anxiolytic-like effects of the aqueous extract of the root of Polygala tenuifolia ( AEPT) using an elevated plus maze (EPM) and hole-board apparatus in mice. The AFPT was orally administered at 50, 100, 200 or 400 mg/kg to ICR mice, 1 h before the behavioral evaluation in the EPM respectively. Control mice were treated with an equal volume of saline, and positive control mice with buspirone (2 mg/kg). Single treatments of the AEPT significantly increased the percentage of time spent and arm entries into the open arms of the EPM vedrsus saline controls (P<0.05). Moreover, there were no changes in the locomotor activity and myorelaxant effects in any group compared with the saline controls. In the hole-board test,single treatments of the AEPT (200 and 400 mg/kg) significantly increased the number of headdips versus saline controls (P<0.05). In addition, the anxiolytic-like effects of the AEPT were blocked by WAY 100635(0.3mg/kg, I.p), a5-$HT_{1A}$ receptor antagonist not by flumazenil, a $GABA_{A}$ antagonist. These results indicate that P. tenuifolia is an effective anxiolytic agent, andsuggest that the anxiolytic-like effects of P. tenuifolia is mediated via the serotonergic nervous system.