• Journal of the Korean Chemical Society
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• v.8 no.2
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• pp.85-87
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• 1964

In order to stabilze alloxan as a reagent for detection of amino acids by spot test, sugars and other reductants were added to the aqueous alloxan solution. It was found that lactose was the best for the purpose. The alloxan reagent containing lactose did not give color change on blank test and was very stable that there was no color change even it was allowed to stand in room temperature for several months. The color reaction with amino acids and some amines was not affected by lactose. This spot test for amino acids is in sensitivity as comparable to that of the previously reported methods and gave color reaction with proline and hydroxyproline to 1${\gamma}$ and 5${\gamma}$ respectively.

• Korean Journal of Hazardous Materials
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• v.2 no.1
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• pp.6-11
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• 2014

There have been frequent chemical leaks over the past 10 years. Particularly, inorganic acids like sulfuric acid, nitric acid, and hydrogen chloride take up 37 % of the total chemical accidents which took place for the past 10 years. When an acid chemical leak happens, fume is generated, diffusing into the air, which might cause serious damage to health of local residents and the environment. However, most of the acid-based chemicals, detecting and analysis methods have not been settled considering the frequency of accidents. In this study, we investigated detection and analysis methods to quickly analyze accident sites and evaluate the impacts on environments. Reviewing local and international test analysis methods of acids suggested that nitric acid, sulfuric acid, hydrogen chloride and hydrogen fluoride can be analyzed with IC. It was also found that UV is better for the analysis of hydrogen fluoride and GC/MS for acrylic acid. The analytical methods suggested in the official test methods basically have limitations of consuming much time at stages of preparation and analysis. Considering prompt responses to chemical accidents, further studies should be done to compare the applicability of rapid monitoring methods such as FT-IR, IMR-MS and SIFT-MS.

• Environmental Analysis Health and Toxicology
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• v.15 no.1_2
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• pp.1-6
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• 2000

This study was designed to evaluated the ecotoxicity to Closterium ehrenbergii using Nonionic surfactants based on its chemical structure. Nonionic surfactants ecotoxicity tended to increase with decreasing the number of ethylene oxide units. The Closterium ehrenbergii test was good in sensitivity and agreement with other published results. The use of Closterium ehrenbergii test offers promising potential for ecotoxicological applications.

• Bulletin of the Korean Chemical Society
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• v.7 no.6
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• pp.444-447
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• 1986

Optically active (R,Z)-(-)-5-tetradecen-4-olide, the pheromone of Popillia japonica Newman was synthesized from (R)-2,3-O-isopropylideneglyceraldehyde as starting material. The biological activity test of the synthetic pheromone as attractant for the male Japanese beetle was tested in Korea.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.2
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• pp.173-180
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• 2005

Metakaolin is a cementitious material for producing high-strength concrete. This material is now used as substitute for silica-fume. In this paper, we did the mechanical and durability test such as compressive/tensile/flexural strength test, chloride ion diffusion, chemical attack and repeated freezing and thawing, carbonation test. In the mechanical tests, 10~15% for binder is optimum substitute rate. And, in the chloride ion diffusion test, according to the increase of substitute of metakaolin & silica-fume for binder, the diffusion coefficient was more reduced. In the chemical attack test, by the filler effect of fine powder such metakaolin and silica-fume, the resistance is more excellent than normal concrete. In the other durability test, the concrete using metakaolin also compared with those of silica-fume substitute concrete. Through these tests, we recognized that metakaolin can be used as a substitute for silica-fume.

• Journal of the Korean GEO-environmental Society
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• v.11 no.12
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• pp.13-18
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• 2010

This study was made on the fact that the environmental impact and durability of the recently developed alkali silicasol chemical grout material. The grout material used for this study was designed to understand its environmental impact and durability through the SEM, chemical resistance test, leaching test, permeability test. In order to compare with the engineering characteristics regarding alkali silicasol grout material and sodium silicate grout material. As a result of SEM, the surface and internal tissues of alkali silicasol grout material could be identified to be denser than those of sodium silicate. As a result of leaching test the adaptability was identified as grout material as it had proved to be an ecological material owing to the total amount of the element to be leached being extremely little. As a result of permeability test it is judged that it is possible to apply the silicasol to the site in the place requiring the water cut-off as the silicasol.

• Fashion & Textile Research Journal
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• v.25 no.4
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• pp.520-533
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• 2023

The present study developed a test protocol for evaluating the mobility of firefighting chemical and flame personal protective equipment (PPE) for the National 119 Rescue Headquarters in Korea and suggested ergonomic design factors to improve their mobility and performance. Six types of PPE were employed, including three types for flame protective PPE (5 ~ 6 kg excluding the self-contained breathing apparatus), and three types for chemical and flame protective PPE (8 ~ 11 kg). These PPEs are used by the 119 Rescue firefighters. Three male firefighters (34.3 ± 1.2 y in age, 175 ± 8 cm in height, 81 ± 13 kg in body weight) participated in the mobility test and interview. A mobility test protocol consisting of 16 components (nine postures and seven motions including a dexterity test) along with a visibility test were developed based on pre-interviews and literature reviews. The findings indicated that the clothing microclimate humidity on the neck and chest exceeded 85%RH on average for all the six PPE conditions, with the chest area reaching as high as 98%RH. This high humidity caused fogging inside the visor and impaired visibility. The requirements for improving the PPE design in terms of mobility varied depending on whether it was the separated types or all-in-one types, particularly regarding the hood and gloves design. The findings of this study can be applied to improve the design of Level A_PPE for firefighters. The mobility test protocol and visibility test developed in this study can also be applied to other types of Level A impermeable PPE.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.5
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• pp.148-155
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• 2017

In this study, by using the international standards ISO TS 16774, Part 2 Test method for chemical resistance as a quality control method of injection type repair material used for leakage crack of underground concrete structure, the performance requirement against of chemical environment of underground concrete structures for repair materials was tested. For this testing 3 types for each of the 2 classes of repair materials(synthetic rubber, cement), with a total of 9 types repair materials, were selected and examined. As a result, the test results showed that the smallest performance deterioration by the change in the mass was with the synthetic rubber(RG) type as opposed to the cement type system, showing that the synthetic rubber type had the strongest relative resistance to chemical exposure. Furthermore, it is necessary to investigate the material with high resistance to chemical substances and to examine the material which can increase resistance to sodium hydroxide and sodium chloride in cement system. These results can be used as a basic index for the selection of repair materials with the strongest resistance to chemical environment found in concrete structures. In addition, it is expected that the test results derived in this study can be used as reference data that can be reflected in the quality improvement of the maintenance material to be developed later.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.1
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• pp.45-50
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• 2014

Effects of wet chemical treatment and thermal cycle conditions on the quantitative interfacial adhesion energy of $Cu/SiN_x$ thin film interfaces were evaluated by 4-point bending test method. The test samples were cleaned by chemical treatment after Cu chemical-mechanical polishing (CMP). The thermal cycle test between Cu and $SiN_x$ capping layer was experimented at the temperature, -45 to $175^{\circ}C$ for 250 cycles. The measured interfacial adhesion energy increased from 10.57 to $14.87J/m^2$ after surface chemical treatment. After 250 thermal cycles, the interfacial adhesion energy decreased to $5.64J/m^2$ and $7.34J/m^2$ for without chemical treatment and with chemical treatment, respectively. The delaminated interfaces were confirmed as $Cu/SiN_x$ interface by using the scanning electron microscope and energy dispersive spectroscopy. From X-ray photoelectron spectroscopy analysis results, the relative Cu oxide amounts between $SiN_x$ and Cu decreased by chemical treatment and increased after thermal cycle. The thermal stress due to the mismatch of thermal expansion coefficient during thermal cycle seemed to weaken the $Cu/SiN_x$ interface adhesion, which led to increased CuO amounts at Cu film surface.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.353-356
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• 2006

Hardening of 2 component adhesive such as epoxy resin used in saturating FRP composite is triggered by mixing each component part within a batch. Chemical reactions occur explosively after a certain time after mixing the batch, viscosity and temperature rapidly increase. As a results, bond performance remarkably decreases and workability declines due to increase in viscosity. Therefore, adhesion should be completed before chemical hardening reaction is rapidly going on. This study examined pot life of structural adhesive for FRP composites by means of change in apparent viscosity and means of exothermic reaction temperature proposing in existing test standards. Result of each test method was compared and analyzed, and reasonable test method and evaluation method are suggested.