• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.1
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• pp.123-129
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• 2007

A 2-step process for the safe destruction of chemical wafare agents(agent hydrolysis followed by supercritical water oxidation) was studied to obtain kinetic data for the pilot plant design. This process is simple to operate by using commercial equipments and could be applied as an alternative technology to incineration. Sarin(GB) and sulfur mustard(HD) were hydrolysed in sodium hydroxide and water respectively and their hydrolysates and OPA, which is binary agent for GB were oxidized in a continuous flow supercritical water oxidation system. Destruction efficiencies of the materials were above 99.99% in supercritical water.

• Journal of the Korean Ceramic Society
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• v.29 no.6
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• pp.419-430
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• 1992

Fabrication possibility of low-shrinkage alumina without oxidation and wetting agent was presented on the basis of observation about oxidation behavior, microstructure and physical characteristics of such reaction agents free Al2O3-Al system. The composition less than Al 10w/o where Al can act as a sintering agent for Al2O3 was excluded. Under the condition of present experiments oxidation of Al2O3-Al system was dependent not on holding time but mainly on oxidation temperature. In thes case of Al powder not comminuted effectively during powder mixing of Al2O3-Al, columnar structure which would act as a hindrance to the densification during sintering developed more during oxidation with higher Al contents, and which made the fabrication of low-shrinkage Al2O3 ceramics impossible. If Al powder was comminuted effectively due to co-mixed Al2O3 characteristics, densification was improved because of no columnar structure and made the fabrication of sintered body with -2.7% dimensional change and 81% relative density possible. As a result, it is possible to fabricate dense low-shrinkage Al2O3 ceramics without oxidation and wetting agent under conditions such as smaller particle size of Al, Al contents below 50v/o, higher green density of Al2O3-Al compact and the use of Al2O3 powder used for high-density ceramics.

• Textile Coloration and Finishing
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• v.29 no.1
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• pp.11-17
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• 2017

In this study, ozone oxidation experiment was carried out for the removal of fluorescent whitening agent which is widely used in textile dyeing and paper industry. The stilbene fluorescent whitening agent has been industrialized since the earliest, and the amount of current production is the highest. Due to the characteristics of the fluorescent whitening agent that can not be removed by conventional wastewater treatment methods, the fluorescent whitening agent in wastewater treatment has difficulty in using as recycled water in the process. Pre-treatment ozone oxidation experiment was conducted prior to the introduction of Membrane Bio Reactor(MBR) treatment process by converting biodegradable materials into biodegradable materials. The removal efficiencies of fluorescent whitening agents, a diaminostilbenedisulfonic acid derivative by ozone oxidation were evaluated by $UV_{254}$ Scan, $COD_{Mn}$, T-N and color using a synthetic wastewater sample ($COD_{Mn}=433.0mg/{\ell}$) and paper and paper mill wastewater ($COD_{Mn}=157.2mg/{\ell}$).

• Journal of the Korean institute of surface engineering
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• v.47 no.4
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• pp.147-154
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• 2014

Formation behavior of PEO (Plasma Electrolytic Oxidation) films on AZ31 Mg alloy was studied in aqueous solutions containing various concentrations of hydroxide ion ($OH^-$) and silicate ion ($SiO_3{^{2-}}$) by voltage-time curves, and corrosion resistance of the PEO film-covered specimen was investigated by immersion test in 0.5 M NaCl solution. From the analyses of the voltage-time curves, it is suggested that two different types of anions are essentially needed for the formation of PEO films on AZ31 Mg alloy: film formation agent and local film breakdown agent. $SiO_3{^{2-}}$ ion acts only as a film formation agent but $OH^-$ ion acts not only as a film formation agent but also film breakdown agent. The PEO films prepared on AZ31 Mg alloy in alkaline silicate solution showed very good corrosion resistance without any pitting or filiform corrosions up to 480 h of immersion in 0.5 M NaCl.

• Textile Coloration and Finishing
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• v.30 no.1
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• pp.51-61
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• 2018

In this study, effluent water was produced through Submerged Membrane Bio-Reactor(SMBR) process, which is a simple system and decomposes organic matter contained in wastewater with biological treatment process and performs solid-liquid separation, Especially, ozone oxidation treatment process is applied to effluent water containing fluorescent whitening agent, which is a trace pollutant which is not removed by biological treatment, and influences the quality of reused water. The concentration of $COD_{Cr}$ in the SMBR was $449.3mg/{\ell}-COD_{Cr}$, and the concentration of permeate water was $100.3mg/{\ell}-COD_{Cr}$. The removal efficiency was about 70.1%. The amount of ozone required for the removal of the fluorescent whitening agent in the permeated water in SMBR was $6.67g-O_3/min$, and the amount of ozone required to remove $COD_{Mn}$ relative to the permeate water was calculated to remove $0.997mg-COD_{Mn}$ for 1mg of $O_3$.

• Journal of dental hygiene science
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• v.9 no.2
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• pp.153-160
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• 2009

The purposed of this study was to investigate the effect of Gold bonding agent as intermediate layer between metal substrate and ceramic coating. Gold bonding agent used to seal off any surface porosity, to mask the greyish color of the metal, and to provide an underlying bright golden hue to the ceramic coverage. The adhesion between metal substrate and ceramic is related to diffusion of oxygen during ceramic firing. The oxide layer produced on non-precious alloy anti titanium was considered to have a potentially adverse effect on metal-ceramic bonding. The oxidation characteristics of titanium and non-precious alloys are the main problem. Every group were divided into test and control groups. Control groups are carried out process of degassing for product oxide layer. Au coating was applied on each Ni-Cr, Co-Cr alloys and cp-Ti specimens with difference surface condition or degassing. Specimens surfaces and cutting plane was characterized by SEM/EDS. Results suggested that Au coating is effective barriers to protect metal oxidation during ceramic firing.

• The Korea Journal of Herbology
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• v.22 no.2
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• pp.51-63
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• 2007

Objectives : For the congenital feeble, the Gongjindan is useful medicine. The experiment is to estimate the value of the Gongjindan as therapeutic agent preventing against aging with an analysis of the ingredients and the bio-activating effects by enzymologic methods. Methods : General ingredients' of the Gongjindan's extract were analyzed first and the quantitative analysis of a reducing sugar, a soluble protein, an amino acid and minerals was made. The Gongjindan, which is extracted, concentrated, and freeze drying with water, ethanol and chloroform, have got applied for the experiment. The effects on electronic donating ability, SOD-like activity, nitric oxide inhibition, xanthine oxidase inhibition, whitening effect have been investigated in the physiological activity measurement of function experiment. Results : The contained amino acid, in order of high amount, is Arginine, Alanine, Glutamic acid, Proline and the contained free amino acid is Glutamic acid, Leucine, Lysine, Phenylalanine. The derivative of free amino acid is ${\gamma}-Aminoisobutyric$ acid, Phosphoserine, Taurine. And the Gongjindan is containing 13 species of minerals in order of Ca>K>Na>Mg>Fe>AI>Mn. Then, to assure of the Gongjindan's capability of anti-oxidation, these following subjects-polyphenol, electronic donating ability, SOD-like activity, nitric oxide inhibition, xanthine oxidase inhibition, tyrosinase inhibition- are analyzed and show high activity especially the most in ethanol extracts. Conclusion : With this analysis of ingredients, the Gongjindan is containing many materials functioning as anti-oxidation, anti-aging, anti-fatigue, neurotransmitter and immune agent. Moreover, In every water, ethanol, chloroform extracts, the Gongjindan's capability of anti-oxidation is confirmed so that we can apply to patients' treatment clinically.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.107-117
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• 2005

The objective of this study was to investigate the proper operation conditions of fenton oxidation such as initial pH, $H_2O_2/Fe^{2+}$ ratio, $H_2O_2/Fe^{2+}$ dosage amount, and neutralizing agent for pretreatment of the livestock wastewater. Fenton oxidation reagents were reacted with the livestock wastewater for 2 hours at 120 rpm and the settling was performed for 2 hours using jar-tester apparatus under the different experimental conditions. And then the supernatant was sampled and measured for the residual $H_2O_2$, $COD_{Cr}$, and SS. The results are as follows; optimum initial pH=4, optimum $H_2O_2/Fe^{2+}$ ratio=10:1, optimum $H_2O_2/Fe^{2+}$ dosage amount=5,000/500 mg/L and $Ca(OH)_2$ as proper neutralizing agent. The removal efficiency of $COD_{Cr}$ and SS were 43% and 84% under those optimal fenton oxidation conditions.

• Preventive Nutrition and Food Science
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• v.4 no.3
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• pp.171-174
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• 1999

For monitoring lipid oxidation development in cooked ground pork during refrigerationm, malonaldehydethiobarbituric acid(MA-TBA) contents were measured using high performance liquid chromatography(HPLC). As the oxidation proceeded during refergeration, TBA-reaction substances(TBARS) absorbances increased and the corresponding HPLC peak areas also increased proportationately. The correlation coefficient between the HPLC peak areas and MA-TBA absorbance were 0.9979. The treatemtn of cetrimide, an ion pairing agent, gave a complete resolution of the MA-TBA complex and the butanol extraction of the complex increased its recovery by 37.8%. Both cetrimide treatment and butanol extraction are essential steps for analyzing MA-TBA complex in ground pork wiht HPLC. A reliable and specific measurement of NA-TBA in ground pork was successfully performed using HPLC.

• Textile Coloration and Finishing
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• v.28 no.4
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• pp.253-270
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• 2016

In the wool textile industry, the necessity for technology development has been steadily raised to create improved fineness and yarn count of existing wool yarns with thick fineness for ensuring higher quality grades of wool yarn. Recently, through controlling fineness of wool yarn for making finer wool in relation with environmentally-friendly and high-sensitivity trend, a differentiated continuous drawing process where the quality of wool can be artificially manipulated has been suggested in the latest textile industry. This study investigated the basic conditions during the continuous drawing process which enable to manufacture wool yarn with fine count by controlling reducing agent treatment, physical drawing and drying after reducing agent treatment, and oxidizing agent post-treatment conditions. Furthermore, this study reviewed the drawing effects by applying the basic conditions for reduction and oxidation reaction in the drawing processes of wool/cashmere, wool/silk, wool/polyester blended yarns as well as such wool yarns. Also, in order to review the practicability, this study examined the physical properties and dyeability of drawn wool yarn applied textile materials in comparison with normal wool yarn applied textile materials.