• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.197-203
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• 1982

The protopectinase from the culture extract of a Verticillium sp. was purified about 1000 fold by ammonium sulfate fractionation, DEAE-Sephadex treatment and Sephadex G-75 column chromatography. The purified enzyme was homogeneous on electrophoresis and its molecular weight was estimated to be 38000 by Andrew's gel filtration, method. The enzyme was almost stable under the temperature of 4$0^{\circ}C$ and within the pH range of 3-5. Its optimum pH and temperature were 4 and 4$0^{\circ}C$, respectively. The activity was markedly inhibited by galacturonic acid. The purified enzyme was able to macerate various kinds of plant tissues, such as radish, cucumber, onion, carrot, and potato. It also reduced the viscosity of pectin solution more rapidly than that of pectic acid solution and showed no lyase or CMCase activity.

• Asian Journal of Atmospheric Environment
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• v.6 no.3
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• pp.137-146
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• 2012

Poor indoor air quality is now worldwide concern due to its adverse impacts on our health and environment. Moreover, these impacts carry a significant burden to the economy. Various technical approaches (e.g., biological, activated carbon fiber (ACF), photocatlytic oxidation (PCO), etc.) have gained popularity in controlling indoor volatile organic compounds (VOCs). This is because removing indoor VOC sources or increasing ventilation rates is often not feasible or economical. This review provides an overview of the various air purification technologies used widely to improve indoor air quality. Although most of these technologies are very useful to remove indoor VOCs, there is no single fully satisfactory method due to their diversity and presence at the low concentration. To achieve technical innovations and the development of specific testing protocols, one should possess a better knowledge on the mechanisms of substrate uptake at VOC concentrations.

• Proceedings of the PSK Conference
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• 2001.04a
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• pp.174.3-175
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• 2001

• Journal of the Korean Chemical Society
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• v.39 no.10
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• pp.799-805
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• 1995

Silane dendrimer with 96 allylic end groups has been synthesized in excellent yield using repetitive alkenylation-hydrosilylation cycles. Each of the two steps provided the products in almost quantitative yields. After a simple chromotograpic purification (silica gel, chloroform), pure dendrimers were obtained and their purity was checked with 1H, 13C NMR spectroscopic method and elemental analysis.

• Journal of the Korean Electrochemical Society
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• v.9 no.1
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• pp.10-18
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• 2006

This article is concerned with the overview of the activated carbon fibers. Firstly, this review provides a comprehensive survey of the overall processes for the synthesis of the activated carbon fibers from the carbonaceous materials. Subsequently, the physicochemical properties such as pore structures and surface oxygen functional groups of the activated carbon fibers were discussed in detail. Finally, as electrochemical applications of the activated carbon fibers to electrode materials for electric double-layer capacitor (EDLC), the electrochemical characteristics of the activated carbon fiber electrodes and the various methods to improve the capacitance and rate capability were introduced. In particular, the effect of pore length distribution (PLD) on kinetics of double-layer charging/discharging was discussed based upon the experimental and theoretical results in our work. And then we discussed in detail the applications of the activated carbon fibers to adsorbent materials for purification of liquid and gas.

• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.19-22
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• 1974

The andalusite that can be found in mica shist near YunChun deposits were studied by means of an optical microscope, X-ray diffraction, thermal analysis of DTA and TGA, chemical analysis and refractoriness test to find out an appropriate method of concentration and purification for the utilization as a raw material of high alumina refractories, with the results: 1. The andalusite are has chiefly contained andalusite, muscovite and biotitei in addition to small amounts of chlorite, kyanite, disapore, quartz, alumandite adn pyrite, which vary from sample to sample. 2. Most of andalusite have occurred as light-red colored columns which are estimated to be an average of 4 by 0.5m/m in length. 3. Samples of andalusite which were dressed by cobbing and hand picking in the deposits have contained an average of 42% andalusite.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.5
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• pp.418-423
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• 2010

Carbon nanotubes (CNTs) were synthesized by Fe-catalytic chemical vapor deposition (CVD) method about $800^{\circ}C$. The influence of process parameters such as pretreatment conditions, gas flow ratio, processing time, etc on the growth of CNTs was investigated by field emission scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. Ammonia was added to acetylene source gas before and during the CNT growth. Different types of CNTs formed depending upon the processing condition. It was found that ammonia prevented amorphous carbons from adsorbing to the outer wall of CNT, resulting in purification of CNTs during CNT growth.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.43-46
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• 2004

Multi-walled carbon nanotubes (MWNTs) produced by chemical vapor deposition were treated with acidic solution for purification and oxidization of CNTs. The surface modification of the oxidized CNTs was achieved by amine treatment and oxygen plasma treatment. The functionalized CNTs were embedded in the epoxy resin by sonication method and the resulting composite was investigated by FESEM. Rheological and mechanical properties of nanocomposites were measured by AR2000 and Instron. The rheological properties and dispersion of modified CNTs/epoxy composites were improved as CNTs were modified, because the modification of CNTs led to a improvement interaction between the CNTs and the epoxy resin. In addition to this, mechanical properties are also improved because of the effective stress transfer between the CNTs and the polymer.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.268-274
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• 2005

Novel antimicrobial substance was isolated from seed coat of Canavalia gladiata by extraction with 75% methanol. Isolation and purification were conducted with solvent fractionation and chromatography on silica gel and sephadex LH-20 columns. Each fraction of antimicrobial activity was tested by paper disc method. Single compound was obtained from the 4th fraction of sephadex LH-20 column chromatography using chloroform/methanol (1:4, v/v), and identified as 3,4,5-trihydroxybenzoic acid methyl ester (methyl gallate) based on HPLC, GC/MS, FT-IR, $^1H$ NMR, and $^{13}C$ NMR analyses. This is the first report describing the presence of methyl gallate in C. gladiata.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.281-285
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• 2001

This technology Provides an economical Production of high value added goods applicable to electro chemicals by recycling of waste products in EGL(Electro Galvanizing Line). The waste products produced in EGL contain potassium chloride (KCI), nickel and zinc. Highly pure KCI and Zinc Chloride which are raw material of electro plating, can be produced by the development of the recycling process. The scope of this study ranges from laboratory experiments to pilot test in plant. We have developed the whole process of recycling technology such as purification method of waste products, fabrication methods of electro chemicals, basic design of plant, pilot scale production and evaluation of pilot goods, Developed electro chemicals were pure enough to satisfy the specification of steel company.