• Korean journal of food and cookery science
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• v.19 no.4
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• pp.470-476
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• 2003

Daehwang (Rheum tanguticum) was extracted by methanol, and the antimicrobial activities of the extract, against some food hazardous microorganisms, were investigated by the paper disc method. The minimum inhibitory concentration (MIC) of the extract against the microorganisms was determined, and the extract components were analyzed by GC/MS. The Daehwang extract showed the strongest antimicrobial effect against P. aeruginosa. The MICs on S. aureus, P. aeruginosa and S. typhimurium were 250, 300 and 300mg/$m\ell$, respectively. In the methanol extracts from Daehwang, 120 different compounds were separated, with the extraction yield of the phenolic compounds being relatively high (29.85%). Substances with antimicrobial activity, such as 2-methoxy-phenol and 4-vinyl-2-methoxy-phenol were detected in the study.

• Journal of the Korean Ceramic Society
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• v.45 no.9
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• pp.531-536
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• 2008

Reaction bonded silicon carbide (RBSC) composite for heat-exchanger was fabricated by molten Si infiltration method. For enforcing fracture toughness to reaction bonded silicon carbide composite, the surface of carbon fiber has coating layer by SiC or pyro-carbon. For SiC layer coating, CVD method was used. And for carbon layer coating, the phenol resin was used. In the case of carbon layer coating, fracture toughness and fracture strength were enhancing to 4.4 $MPa{\cdot}m^{1/2}$ and 279 MPa.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.2
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• pp.139-148
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• 1995

This study was carried out to investigate the effects of super heated steam on the physical and chemical changes of burley cut tobacco. Total sugar, total alkaloid, ether extracts, crude ash, total nitrogen and pH for leaf chemical constituents were analyzed. Filling power and fineness index for physical properties, and carbonyl compounds, phenol compounds, amonia, pH, hydrogen cyanide nicotine, carbon monoxide, total volatile base and tar for smoke components were also analyzed. The cut tobacco treated with super heated steam showed significant decrease in total sugar and total alkaloid. The filling power of the sample treated with the super heated steam system was increased abruptly when heated at over 250℃. The fineness index showed similar tendency to that of common toast method. Super heated steam treatment slightly decreased carbonyl compounds, phenol compounds, hydrogen cyanide, nicotine, carbon monoxide and tar in the tobacco. Especially the decrease of ammonia was the most remarkable. The pH of smoke was a little different compared with that in the common toast. The sensory test results showed that, compared to the common conveyer moving system, the tobacco treated with super heated steam system brought out more roasted flavor, lowered impact, irritation, and sting, further improved aftertaste, and lowered bitterness. The super heated steam treatment method used in the studies is expected to give better filling power, mild taste and toasted odor of tobacco than that of the common method for toast treatment. Key words : burley tobacco, super heated steam, expansion, toast.

• Journal of the Korea Furniture Society
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• v.25 no.3
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• pp.207-212
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• 2014

With increased interests in environmental issues, people are looking for new materials that serve special and bio-activated functions. One of interesting materials is charcoal which has excellent adsorption ability for harmful volatile organic compounds, fireproof performance, far-infrared ray emission, and electromagnetic shielding. Since non-crack carbonized board was developed from wood-based composite materials, carbonization method might be applied to woodcraft products such as wood cup and bamboo. In this study, manufacture of wood charcoal bowl was conducted with carbonization method developed in 2009 in order to activate wood products market. Ash tree(Fraxinus rhynchophylla) cup was carbonized at $600^{\circ}C$ with two pretreatments which were phenol resin and wood tar solution treatment. After carbonization of ash tree cup, non-crack charcoal cup were successfully manufactured. Phenol resin treatment affected on charcoal cup manufacturing both positively and negatively. For a positive way, it prevented shrinkage. For a negative way, it decreased water repellency. On the contrary, wood tar treatment accelerated shrinkage a bit and increased water repellency. Based on the results, wood tar can be used as pre-treatment solution for reducing post-treatment costs. We confirmed woodcraft products can be carbonized without deformation, so carbonization may provide a high value-added products from wood.

• Journal of Environmental Science International
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• v.23 no.10
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• pp.1693-1701
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• 2014

A rapid and simple method for the quantitative determination of volatile fatty acids (VFAs; propionic acid, n-butyric acid, i-valeric acid and n-valeric acid) and indoles (phenol, p-cresol, 4-ethyl phenol, indole and skatole) in pig slurry and dog excrement using solid-phase micro-extraction (SPME) coupled to gas chromatography was evaluated. $50/30{\mu}m$ DVB/CAR/PDMS (Divinylbenzene/Carboxen/Polydimethylsiloxane) fiber was used to extract the target compounds in aqueous media. Sample amount and adsorption time was standardized for the routine analysis. Detection limits were from 0.11 to $0.15{\mu}gL$ for VFAs and from 0.12 to $0.28{\mu}gL$ for indoles and the correlations observed ($R^2$) were 0.975~1.000. This method was applied to the pig slurry, fertilizer, compost and dog excrement. In nearly all cases, the indoles were detected in concentrations of higher than their limits of detection (DOLs). But the VFAs in swine manure were below their DOLs.

• Environmental Engineering Research
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• v.10 no.3
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• pp.144-154
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• 2005

The use of ozone gained acceptance in the production of ultrapure water because of its powerful oxidizing ability. Ozone is currently used to deactivate microorganisms and remove organic contaminants. However, interest also exists in using radical species, which arc stronger oxidants than ozone, in such processes. One means of producing radical species is by corona discharge. This work investigates the use of a novel pulseless corona-discharge system for the removal of organic substances in ultrapure water production. The method combines corona discharge with electrohydrodynamic spraying of oxygen, forming microbubbles. Experimental results show that pulseless corona discharge effectively removes organics, such as phenol and methylene blue, in deionized water. The corona-discharge method is demonstrated to be comparable to the direct use of ozone at a high-applied voltage. The results also show that a minimum applied voltage exists for operation of the corona-discharge method. In this work, the minimum applied voltage is approximately 4.5 kV. The kinetic rate or phenol degradation in the reactor is modeled. Modeling results show that the dominant species of the pulseless corona-discharge reactor are hydroxyl radical and aqueous electron. Several radical species produced in the pulseless corona-discharge process are identified experimentally. The. major species are hydroxyl radical, atomic hydrogen species, and ozone.

• YAKHAK HOEJI
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• v.44 no.5
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• pp.416-423
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• 2000

There is a growing concern that a wide variety of chemicals released into the environment can disrupt the endocrine system of fish, wildlife and humans. Endocrine disrupting chemicals (EDCs) include pesticides such as DDT lindane and atrazine, the food packaging chemicals, phthalates and bisphenol A, alkylphenol ethoxylate detergents and the chemical industry by-products, dioxins. Xenoestrogens in the environment have been argued about health risk, because of estrogen mimetic chemicals are exposed only small amounts to human. A number of in vivo and in vitro assays are now in use to assess the activity of xenoestrogens in the environment. A human breast cancer cell line (MCF-7) was used to develop in vitro screening assay for the detection of xenoestrogenic environmental pollutants. The E-SCREEN (MCF7-BUS) assay is proposed as a reliable, easy and rapid-to-perform method. To optimize and validate this method before it can be used routinely, several phenol compounds and pesticides suspected to be estrogenic were tested using I-SCREEN assay. The results showed that this method is a valuable tool for screening potential estrogen-mimicking environmental pollutants and quantitative determination of estrogeniciy.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.591-597
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• 2003

To compare the quality of genomic DNA extracted from potato for PCR detection, four different methods, such as silica-based membrane method, silica-coated bead method, STE solution treatment, and CTAB-phenol/chloroform method, were evaluated. Also, to remove an excessive carbohydrate from the potato, ${\alpha}$- and ${\beta}$-amylase were used individually and in combination. When used both silica-based membrane method and silica-coated bead method combined with enzymes, the genomic DNAs were extracted from the raw potato with high purity for PCR. However, the silica-coated head method combined with enzyme treatment was the most efficient for extraction of the genomic DNA from the frozen fried potatoes. When applied with STE solution, the highly purified DNA was extracted from the raw potatoes without enzyme treatment in adequate yield for PCR. In cases of processed potatoes, such as frozen-fried potato and fabricated potato chips, CTAB-phenol/chloroform method is mostly feasible for DNA extraction and PCR efficacy at high sensitivity. As the results of PCR amplification, 216bp of PCR product was detected on 2% agarose gel electrophoresis, but any amplicons derived from New leaf and New leaf Y gene was not detected in any sample.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.129-132
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• 1991

The volatile components of Perillae folium were isolated by simultaneous steam distillation-extraction method, and analyzed by combined GC and GC-MS. Among seventeen components indentified 6 alcohols (3-octanol, 1-octen-3-ol, linalool, nerolidol, supathuleol and phytol), 2 ketones, 1 aldehyde, 1 phenol and 7 hydrocarbons were confirmed. The most abundant component was myristicin comprising about 53.4%.

• Fashion & Textile Research Journal
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• v.4 no.1
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• pp.86-91
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• 2002

To estimate dispersion stability of particles, suspending power and particle size were examined as functions of pHs, surfactants, electrolytes and ionic strengths using ${\alpha}-Fe_2O_3$ particle as the model of particulate soil. Suspending power and particle size were determined by UV-Vis spectrumeter and by light scattering using the polarization ratio method, respectively. The suspending power was relatively high with polyanion electrolytes and was low with neutral salts. The suspending power was biphasis, minimum pH 6~7, and the effect of surfactant on the suspending power was insignificant. Generally suspending power increased with decreasing the particle size governed aggregation of dispersed particles regardless of solution conditions. Hence the suspending power was inversely related to the particle size.