• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2644-2648
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• 2010

Catalytic conversion of structurally different epoxides to the corresponding 1,2-diacetoxy esters was carried out readily with phosphomolybdic acid alone or its supported on $SiO_2$. The reactions were carried out under solvolytic or solvent free conditions within 5-15 min at room temperature. The product 1,2-diacetates were obtained in high to excellent yields. Supporting of phosphomolybdic acid on $SiO_2$ showed the better catalytic activity than $Al_2O_3$. Conversion of optically pure R-(+)-styrene oxide to S-(+)-1,2-diacetoxy-1-phenylethane was carried with phosphomolybdic acid in high yield and stereospecificity.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.277-280
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• 2004

TCE and PCE, suspected carcinogens, are the most common groundwater pollutant from extensive use as a solvent and degreaser. Escherichia coli TGI pBSKAN TOM Green and E. coli TGI pBSKAN ToMO, which were used DNA shuffling technique, produce Toluene-o-monooxygenase(TOM) and toluene-o-xylene- monooxygenase(ToMO). These cells and enzymes are degrading TCE and PCE, TOM and ToMO are needed to cofactor, such as NADH, NADPH and other cofactors. Used TCE and PCE degrading microorganisms experiment the contaminated material removal efficiency. A shunting test used NAD and Hydrogen peroxide.

• 한국미생물·생명공학회지
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• 제27권2호
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• pp.159-165
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• 1999

Pseudomonas aeruginosa JRT-4 strain was used as a biosurfactant-producing microorganism in this study. It was one of the microorganisms isolated from the sewage sludge, the main and branch streams of Han river. The surface tension of the culture broth of P. aeruginosa JRT-4 decreased to 30mN/m. The crude biosurfactant was obtained from the culture broth by acid precipitation, solvent extraction, evaporation, and freeze drying. The CMC value of the crude biosurfactant was 0.006%(w/v). From analysis of the chemical structure of biosurfactant, it was determined as rhamnolipid 1 and 3 structures by FAB mass spectrometer. In the washing test for artificially contaminated textiles, the biosurfactant showed better bleachness than the two chemically synthesized surfactant, LAS and SLES. Finally, the biodegradation and ecotoxidolorical tests showed that the biosurfactant was readily biodegradable in the environment and a mild material for microorganisms and green algae.

• 대한가정학회지
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• 제30권2호
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• pp.35-43
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• 1992

This study is to investigate the problems of pollution caused by drycleaning solvents. From the problem of each solvents, safety count-step have to set up. It is following. 1) Solvent: Smong phenomenon of optical chemistry. It has to develop safety tumbler that is attached retrievable device. 2) Perchloroethylene: Pollution of underground water and cause of cancer. Considering the influence on environment and human bing, it has to set up more strong safty plan than now. 3) Chlorofluorocabon : Destory of ozon layer and green house effect on earth. It is being to stop the production until the early part of the year 2000. So it is developing a substitute for chlorofluorocarbon. 4) 1,1,1-trichloroethane : Pollution of underground water and destroy of ozon layzer. At the end of the year 2004, there will be end production of it.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.2871-2876
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• 2013

We present an efficient and new preparative method for the symmetric ${\beta}$-diketimines assisted by microwave. A series of N,N'-symmetrically alkyl substituted ${\beta}$-diketimines have been synthesized from the reaction of O-acylation with dimethylsulfate. Higher reproducibility and yield, lower cost and much improved green nature originated from no solvent condition and higher energy efficiency due to faster reaction time are major merits of this new method. In addition to these merits, almost every kind of ${\beta}$-diketimines including alkyl-substituted ${\beta}$-diketimines little reported yet has been successfully prepared. Much wider applications of these compounds in various fields are expected.

• 대한화학회지
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• 제53권5호
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• pp.536-541
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• 2009

무용제하에서 $\alpha$-히드록시 인산염을 합성하기 위해 술팜산은 비용효율이 높고 일반적인 산들의 친환경적인 대안으로 활용되었다. 초음파 조사를 이용하여 더 나은 수율을 얻었고 반응시간이 짧았다.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.825-828
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• 2009

Alum $(KAl(SO_4)_2{\cdot}12H_2O)$ is an inexpensive, efficient, non‐toxic and mild catalyst for the synthesis of bis(indolyl)methanes by the reaction of 1H-indole with various aldehydes/ketones under the influence of ultrasound irradiation in solvent‐free condition. The remarkable advantages of this method are the simple experimental procedures, shorter reaction times, high yields of product and green aspects by avoiding toxic catalysts and solvents.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.215-216
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• 2006

To lower the cost of MIM products, the gate and runner materials and green parts with defects are usually recycled. It is necessary to understand what causes the recycled products to deteriorate. The results show that the viscosity of the 1R (recycled once) feedstock was slightly lower than that of the fresh material. However, as the number of recyclings increased, the viscosity increased, while the density decreased, and more defects were noticed duri ng solvent debinding. These deteriorations were mainly caused by the increase of the melting point of the backbone binder and the oxidation of the filler or paraffin wax.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.282-292
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• 2018

This study aimed to compare the chemical composition of Morus nigra leaves extracts, obtained by maceration, accelerated solvent (ASE) and supercritical fluid extraction (SFE) under different extraction conditions. With regards to chemical composition, mainly phenolic acids and flavonoids were identified. HPLC-ESI-QTOF-MS allowed the identification of 13 new compounds reported in M. nigra leaves for the first time. ASE as a fast, green and innovative approach, seems to be the best choice for extracting compounds of different polarities within the shortest extraction time. The present study also highlights the potential application of M. nigra extracts as constituents of new added-value formulations.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.109-122
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• 2018

This work highlights extraction and removal of Lignosulfonate using sunflower oil-Tri-n-octylamine (TOA) system in bulk liquid membrane transport. Maximum extraction and recovery percentages of 92.4% and 75.2% were achieved. Optimum manifold operating conditions were: 4 vol.% TOA, $2{\pm}0.1$ feed phase pH, 300 rpm stirring speed, at $40^{\circ}C$ with 0.2 (M) $Na_2SO_4$ solution. 1:2 (organic/aqueous) and 1:1 (aqueous/aqueous) phase ratios produced best results. Extraction (36.85 kJ/mol) was found to be intermediate controlled and stripping (54.79 kJ/mol) was chemical reaction controlled. Kinetic estimation of data with higher rate constants for stripping vis-${\grave{a}}$-vis extraction showed latter to be rate determining.