• Journal of the Korean Applied Science and Technology
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• v.24 no.4
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• pp.383-392
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• 2007

This paper is studied on the efficient purification process of dimethyl carbonate (DMC) from the melt layer crystallization combining crystallization process, sweating process and distillation recovery process. Purity and yield of DMC crystal depended mainly on the crystallization temperature, cooling rate, sweating termperature sweating rate. Through the optimization of crystallization and sweating operation, DMC crystal can be upgraded to very high purity over 99.9% and high yield over 85%.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.330-336
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• 2014

Purification of indole contained in model coal tar absorption oil was examined by extraction-distillation-crystallization combination. The absorption oil consists of nine components such as four kinds of nitrogen heterocyclic compounds (9.2% quinoline, 2.4% iso-quinoline, 4.7% indole, 2.4% quinaldine), three kinds of bicyclic aromatic compounds (14.2% 1-methylnaphthalene, 31.8% 2-methylnaphthalene, 23.5% dimethylnaphthalene), 5.5% biphenyl and 3.3% phenyl ether. 99.5% indole was recovered by combination of formamide extraction-distillation-solute crystallization using n-hexane. Furthermore, the recovery process of indole contained in coal tar absorption oil was studied by using the experimental results obtained by each operation of this work.

• Journal of Photoscience
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• v.9 no.2
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• pp.323-325
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• 2002

Bacillus Anthracis is the causative agent of anthrax. The major virulence factors are a poly-D glutamic acid capsule and three-protein component exotoxin, which is collectively known as anthrax toxin, protective antigen (PA, 83 kDa), lethal factor (LF, 90 kDa), and edema factor (EF, 89 kDa). These three proteins individually have no known toxic activities, but in combination with PA form two toxins (lethal toxin and edema toxin), causing different pathogenic responses in animals and cultured cells. However, it remains to be elucidated for pathogenic mechanism of anthrax toxin. In this study, we constructed toxin component in bacterial overexpression system and purified the native toxin from Bacillus anthracis delta sterne F32 using FPLC system. Recombinant toxin showed high homogeneity and rapid purification processes. Also, this recombinant toxin was comparable to B. anthracis native toxin in terms of cytotoxic effects on cultured cell lines.

• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.23-28
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• 1974

1. Stage crushing by jaw crusher, steel mortar, and ball mill in turn has shown an inclination to increase the distribution of andalusite in coarse particles as well as to increase that of micas in fine particles. 2. Water elutriation was effective for the removal of muscovite and magnetic separation was effective for that of Mg-Fe micas such as biotte and chlorite. The process of concentration and that of purification are diagramatized respectively as follows: Concentration; Raw andalusite${\lightarrow}$Crushing${\lightarrow}$Screening${\lightarrow}$Water elutriation${\lightarrow}$Magnetic separation Purification; Concentrated andalusite${\lightarrow}$Calcination${\lightarrow}$Ball milling${\lightarrow}$Screening${\lightarrow}$Water elutriation${\lightarrow}$Magnetic separation${\lightarrow}$Acid washing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.4
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• pp.398-403
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• 2003

The purpose of this paper is to investigate purification characteristic of soil-bentonite landfill liner and to develop a desirable liner system. In order to clarify the purification characteristics, high pressure column tests using soil-bentonite, reactive soil-bentonite and reactive bentomat were carried out in the presence of water and leachate. The test results indicated that the significant amount of NH$_3$-N, Pb and Cu was removed through the reactive soil-bentonite liner system.

• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.176-180
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• 2000

Microbial protease has been interesting due to the biological roles in the producing microorganism. A thermophilic Actinomyces produing protease was isolated from soil. The optimal medium composition and culture conditions for maximum protease production was as follows 0.5% soluble starch, 0.5% yeast extract. 0.1% K2HPO4, 0.05% CaCl2, initial pH 8.0 at 50$^{\circ}C$ for 48hours. The protease was purified by the procedure of ammonium sulfate precipitation, anion exchange chromatography(LC), DEAE high performance liquid chromatography and GPC HPLC. The purification fold of the purified enzyme was increased about 22.6. The optimal pH and temperature for reaction of the purified enzyme were 7.5 and 60$^{\circ}C$. The purified enzyme was stable for the pH range from 6.0 to 8.5, but was unstable when treated at 80$^{\circ}C$ for 10 minutes. The activity of the enzyme was inhibited by Ag+ and Cu2+.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.06a
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• pp.27-38
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• 1995

Based on innovative membrane module concepts reverse osmosis and nanofiltration are going to become important instruments in environmental engineering. One example is the Disc-Tube-module and its application for the purification of landfill leachate. Currently over 45 different landfills are using this ROCHEM DT-module, in some cases combined with the high pressure reverse osmosis versions of this module, operating at up to 120 bar and 200 bar. This state of the art membrane technology and the DTF-module for nanofiltration, developed by ROCHEM on the basis of the DT-module and RO-systems for the purification of landfill leachate, make possible in hybrid processes permeate recovery rates of more than 97 % with concentration factors up to 40.

• Journal of Environmental Science International
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• v.16 no.2
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• pp.197-202
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• 2007

Formaldehyde is a typical indoor air pollutant that has numerous adverse health problems in modern living conditions. Phytoremediation that use plants to remove contaminants from polluted media can be applied to improve indoor air quality. Two sets of experiments; 1) two rooms in newly built auditorium and 2) a bed room in 2-year-old apartment; were performed to investigate plant effects on indoor formaldehyde concentration. It was observed from the experiments that plant can help decontaminating formaldehyde at low concentration level (0.1 ppm) but the effects decreased considerably at hish concentration (1ppm). The purification effects of indoor plant also showed the periodic pattern due to its physiological activity. More purification was observed as increasing plant density in the bed room but the formaldehyde concentration returned the original concentration level in two days after removing plants. It was suggested from the results that air purification using plants is an effective means of reduction on indoor formaldehyde level, though, reduction of source is highly desirable when the concentration level is high. The results also suggest that introducing supplementary purifying aids and/or efficient ventilation could be considered due to periodic removal pattern of plant.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.387-395
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• 2006

To isolate and purify anti-fungal active substances from immunized housefly (Musca domestica), low dose of Candida albicans was injected into the larvae of the housefly to induce the appearance of potent anti-fungal active substances in the hemolymph. This purification work was performed by the routine isolation and purification processes of protein, namely, solid phase extraction (SPE), SDS-PACE electrophoresis, HPLC purification. Three 4-16 kDa peptides which exhibited antifungal activity against Candida albican and other fungi were isolated from induced hemolymph. Consequently, further anti-fungal activity study showed that these three peptides were different either in molecular weight or in anti-fungal activity. All isolated substances were proved to be active and resistant to high-temperature. It was deduced that these peptides isolated from induced housefly were novel members of the insect defensin family and they were inducible.

• The Plant Pathology Journal
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• v.15 no.1
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• pp.34-37
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• 1999

Cymbidium mosaic virus (CyMV) was purified from CyMV infected orchid plant leaves by Sephacryl S-500 HR column chromatography. Partial purification was done by solubilization with Triton X-100 (alkylphenoxypolyethoxy ethanol) and precipitation with polyethylene glycol (PEG 6,000) followed by ultracentrifugation on 30% sucrose cushion. Based on the spectrophotometric analysis, 33 mg of CyMV could be obtained form 100 g of CyMV-infected orchid plant leaves. The purified CyMV represented one distinct homogeneous band by SDS-PAGE, and electron microscopy revealed that it was highly homogeneous and not fragmented. Bioassay demonstrated that the purified CyMV had a normal infectivity to Chenopodium amaranticolor and orchid plants. Based on these results, the purification method in this work could be served as an improved method for the purification of CyMV and similar viruses with good yield, high purity and native integrity.