• 한국염색가공학회지
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• 제17권1호
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• pp.38-44
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• 2005

Oxidation method was used to extract S-keratose from wool. Wool was treated with performic acid and soluble fraction(S-keratose) was collected by evaporating the solvent. S-keratose and Nylon 6 were dissolved in formic acid at the ratio of 100/0, 80/20, 50/50, 20/80, and 0/100, and S-keratose/Nylon 6 web of sub-micron size was made by electro-spinning technique. SEM, EA, FT-IR, XRD, and TGA were used to characterize the properties of S-keratose/Nylon 6 solutions and electrospun fibers. As the Nylon 6 content increased, viscosity, conductivity of the electrospinning solution and the diameter of spun fiber increased. Electrospun nonwoven webs have the same S-keratose/Nylon 6 ratios of the spinning solutions. The crystalline structures of S-keratose and Nylon 6 existed separately in the electrospun webs. Thermal stability of the webs increased due to Nylon 6 content.

• 생약학회지
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• 제39권3호
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• pp.194-198
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• 2008

Artemisia capillaries is a major important food and medicinal resource in Korea. In order to confirm the biological activities of Artemisia capillaries, we investigated antioxidant and anticancer activities from in vitro assays. The Artemisia capillaries methanol (MeOH) extracts was used for the evaluation of DPPH scavenging, total phenolic content, total flavonoid content, hydroxyl radical (${\bullet}OH$) scavenging, reducing power assay as antioxidant activity, as well as anticancer activities as MTT assay. As a result, the Artemisia capillaries MeOH extracts showed potent antioxidative activity and anticancer activity in vitro. These results suggest that the Artemisia capillaries MeOH extracts have a potential alleviated oxidation process, cell motility activity, and tumorigenesis.

• 한국의류학회지
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• 제20권2호
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• pp.270-281
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• 1996

This study was carried to figure out the effect of bleaching on the cationic surfactant (DSDMAC) absorption by cotton fabrics. And physico-chemical change, static electricity, and fabric stiffness of bleached cotton fabrics were measured. Cotton fabrics bleached with sodium hypochlorite soluton and with sodium percarbonate solution were used to analyze the DADMAC absorption. The results were as follows: 1. As the number of bleaching cycles were increased, the degree of oxidation on cotton fabrics was increased. So their carboxyl content was increased and their tensile strength was decreased. 2. DSDMAC absorption by cotton fabrics was increased by bleaching and was in propor- tion to carboxyl content. Therefore, it was groved that DSDMAC absorption by cotton fabrics was motivated by ion exchange mechanism. 3. The static electricity of cotton fabrics almost no change when bleached and unbleached absorption had no effect on the static electricity of cotton fabrics. 4. DSDMAC which was absorbed by cotton fabrics acted as a lubricant. DSDMAC absorption reduced the friction coefficient of yarn, so stiffness of cotton fabric was decreased.

• 반도체디스플레이기술학회지
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• 제13권3호
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• pp.13-19
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• 2014

Phosphoric acid was used as etching agent instead of conventional peroxide - based chemicals for forming pattern of ultra definition display. Etchant was synthesized by mixing etching agent, oxidation agent, buffer solution, and additive into solvent, deionized water. Thicknesses of copper, main metal of ultra definition display, for etching, were 10,000 and $30,000{{\AA}}$. Etch stop of good low skew for proper pattern formation has been occurred at the content ratio of phosphoric acid 60 - 64%, nitric acid 4 - 5%, additive(potassium acetate) 1 - 3%. Buffer solution(acetic acid) decreased the metal contact angle $63.07^{\circ}$ to $42.49^{\circ}$ for benefiting pattern formation. Content variations on four components (phosphoric acid, nitric acid, acetic acid, potassium acetic acid) of the etchant with storage time were within 3 wt% after 24 hrs of etching work.

• 동아시아식생활학회지
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• 제4권2호
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• pp.51-57
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• 1994

Six sesame oils prepared from Korean and Chinese sesame were oxidized at 40$^{\circ}C$ for 16 weeks in a dark place. Effects of oxidative stability on tocopherols of those sesame oils were studied in related to chemical changes in the oils. All oil samples showed that the rate of tocopherol reduction was increased by the storage time. The changes of peroxide value, free fatty acid, carbonyl content were not caused in direct relation to the tocopherols oxidation. The amount of total tocopherol in the Korean sesame oil ranged from 48.7-50.3mg/100g and Chinese seseame oil ranged from 42.4-44.7 mg/100g According to the three individual tocopherols remaining content after 16weeks, ${\gamma}$-,${\alpha}$-,${\beta}$- tocopherol showed 70%, 30%, 20% of initial concentrations in the oils respectively. There was no significant difference between Korean and Chinese sesame oil except the higher total amount of the tocopherol in Korean sesame oil than that of Chinese.

• Korean Chemical Engineering Research
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• 제56권5호
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• pp.738-751
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• 2018

The effect of the reaction temperature and reaction time on the thermal oxidative purification quality of detonation nanodiamond (NDsoot) was investigated in a gas-solid fluidized bed reactor of a $0.10m-ID{\times}1.0m$-high stainless steel column with zirconia beads ($d_{SV}=99.2{\mu}m$). The carbon conversion increased with increasing the reaction temperature; however, when the reaction temperature was greater than 773 K, the carbon conversion did not increase. The content of $sp^3$-hybridized carbon at the reaction temperature of 703 K barely changed when the reaction time was more than 30 minutes, but at 773 K, the content decreased as preferred. At 703 K, the purification quality increased with the increasing reaction time; however, at 773 K, the purification quality increased up to 30 minutes and then decreased rapidly.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.29-30
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• 2013

Steel corrosion is the most serious problem in RC structures. Even though patch repair method is normally applied in repair system, the effectiveness is not enough. Cathodic protection in active repair method to deteriorated RC structures. FEM model was developed to simulate the optimized cathodic protection condition. Iro oxidation, hydrogen evolution and oxygen reduction were considered to expect current distribution. Moisture content in concrete which can affect the electrolyte conductivity was used as initial condition.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.144-147
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• 2000

The effect of accelerated aging test on ethylene-propylene-diene monomer(EPDM) rubber used for outdoor insulation was studied by X-ray photoelectron spectroscopy(XPS), scanning electron microscope(SEM), FFT spectrum alalysis, and electrical pulse counts using PC by oscilloscope(300 MHz). In electrical alalysis, FFT spectrum analysis indicated arcing caused a significant increase in the third harmonic content of the leakage current of polluted insulator. Also, pulse counts increased as aging time. The surface oxygen and aluminum content were found to increase and that of carbon and nitrogen were found to decrease with time. The detailed XPS analysis indicated that the concentration of carbon in C-C decreased and concentration of highly oxidized carbons increased with time, which was due to the oxidation of EPDM rubber polymer SEM analysis indicated that crack and erosion of EPDM rubber occurred with time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.243-247
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• 2003

The effect of accelerated weathering(UV) on three type of ethylene propylene diene monomer(EPDM) composite used for higher voltage insulator were investigated by weather-emoter. For weatherability of EPDM composite, surface resistance, dielectric breakdown strength, change of contact angle, surface composition were measured according to UV accelerated weathering time. From the resort of the measurement of surface resistivity, contact angle of EPDM composite decreased and showed chalking and cracking phenomenon when UV weathweing time was for 1500 h and 2000 h. The analysis of surface atomic composition indicated that surface aluminiu(Al) content was detected due to chalking phenomenon after 1500 h of UV weathering, Oxygen content of all composite increased due to the oxidation.

• 펄프종이기술
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• 제43권1호
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• pp.29-35
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• 2011

Since the role of lignin in the wood cell wall is to keep integrity and structure rigidity of lignocellulosic substrate, lignin of the cell wall has to be destroyed before enzymatic hydrolysis of wood polysaccharides. The aspen wood meals were delignified with ozone in acidic condition. The chemical characteristics of wood meal were investigated. The 60% of lignin and almost zero % of polysaccharides in aspen wood meal was degraded with 10min. ozone treatment. The phenolic hydroxyl groups of lignin in ozonated wood meal were increased with ozonation time. The sugar composition of ozonated wood meal showed that the hemicellulose was more susceptible to ozonation than cellulose. The yield of aldehyde was increased in some degree with 10min. ozone treatment and decreased with longer ozone treatment.