• Journal of the Korea Concrete Institute
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• v.25 no.3
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• pp.347-354
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• 2013

Recently, crushed fine aggregates are being widely used due to the shortage of natural sand. In Korea, the amount of fine particles under 0.08 mm contained in crushed fine aggregates is restricted to be less than 7%, which is similar to the regulations of ASTM but is still very strict compared to the regulations of the other nations. In addition, the crushed aggregates already have in them about 20% of fine particles under 0.08 mm which occurs while they are crushed. The fine particles are not easy to wash out, and also to maximize the use of resources it is deemed necessary to review the possibility of enhancing the limit of the amount of fine particles. Therefore, this study conducted experiments to analyze the characteristics of fine particles under 0.08mm and their influence on the properties of concrete. Experiments using silt and cohesive soil were also done for comparison. In the experiments on fine particles, the methylene blue value was more in the soil dust contained in silt and cohesive soil than in the stone powder contained in crushed fine aggregates. Also, the methylene blue value had a close correlation with packing density and liquid & plastic limit. In the experiments done with concrete, the quantity of high range water reducing agent demanded to obtain the same slump increased as the fine particle substitution rate heightened. However, in the experiment which used stone powder testing the compressive strength and tensile strength of concrete in the same water-cement ratio, there was little change in strength with less than 20% addition of fine particles among the fine aggregates, and no meaningful difference in the amount of drying shrinkage of concrete.

• Resources Recycling
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• v.17 no.1
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• pp.20-28
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• 2008

Leather waste discharged from Shinpyung Changrim Industrial Complex contained 46.3 percent of carbon, and weight loss of leather waste about 50 percent was observed at $500^{\circ}C$ by thermogravimetric analysis. Chemically activated carbon [LW4AC] was made at activation temperature of $800^{\circ}C$ during 30 minutes in electric furnace. Iodine value and decoloration of methylene blue was 968 mg/g and 158 mL/g, respectively. We found that pore volume was more developed according to the increase in the ratio of $K_2CO_3/LW$.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.8
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• pp.817-822
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• 2008

In this study, the photocatalytic degradation of methylene blue in TiO$_2$ particles-dispersed water solution was carried out by irradiating microwave and UV light simultaneously. A microwave-discharged electrodeless UV lamp was developed to use microwave and UV simultaneously for photocatalytic reactions. The results of photocatalytic degradation of methylene blue showed that the decomposition rate increased with the microwave intensity, the circulating fluid velocity, and the amount of TiO$_2$ particles and auxiliary oxidizing agents added. Especially, the rate constant of H$_2$O$_2$-added photocatalytic reaction increased about three times from 0.0075 min$^{-1}$ to 0.0250 min$^{-1}$ when microwave was additionally irradiated. This study demonstrates that the microwave irradiation can play a very important role in photocatalytic degradation using peroxides although it is not easy to quantitatively assess the effect of microwave on photocatalytic reactions from the experimental data of this study.

• Journal of the Korean Wood Science and Technology
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• v.34 no.1
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• pp.40-51
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• 2006

The objective of this research is to analyze a possibility for the utilization of carbonized bark and develop the technique for carbonization of bark for using as the adsorbent, the soil improvement agent, the carrier for microbial activity, health products, and so on. The properties of bark charcoals such as methylenehlue adsorption (MBA), equilibrium moisture content (EMC), far infra rad emissivity, pH, water retention and caloric value were analyzed. The MBA values of bark charcoals carbonized for 8 hr of carbonization time at $800^{\circ}C$ of carbonization temperature for Larix leptolepis, Pinus koraiensis, Pinus rigida were greater than 110 mg/g. The bark charcoals pH values of all three species that were carbonized for 4 hr of carbonization time at $400^{\circ}C$ of carbonization temperature was 6.6 and carbonized for 4 hr at 600 and $800^{\circ}C$ was about 9. Therefore the bark charcoals of those species could be used as charcoals if the carbonization temperature and time were controlled.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1063-1068
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• 2008

The photocatalytic degradation of methylene blue water solution was carried out by irradiating microwave and UV light simultaneously using $TiO_2$ photocatalyst balls prepared by Chemical Vapor Deposition method. A microwave-discharged electrodeless UV lamp was developed to use microwave and UV simultaneously for photocatalytic reactions. The results of photocatalytic degradation of methylene blue showed that the decomposition rate increased with the microwave intensity, the circulating fluid velocity and auxiliary oxidizing agents added. Especially, the rate constant of $H_2O_2$-added photocatalytic reaction increased about three times from $0.0061min^{-1}$ to $0.0197min^{-1}$ when microwave was additionally irradiated. This study demonstrates that the microwave irradiation can play a very important role in photocatalytic degradation using peroxides although it is not easy to quantitatively assess the effect of microwave on photocatalytic reactions from the experimental data of this study.

• Journal of the Korean Applied Science and Technology
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• v.38 no.2
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• pp.434-440
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• 2021

This study aimed to understand the effects on the improvement of hair texture by producing a hair texture improvement agent with milk thistle oil, and then applying it to the damaged hair. Each sample before and after application was measured. To understand the effects on the improvement of hair texture, the tensile strength, absorbance with the use of methylene blue, and gloss were measured. In the results of measuring the tensile strength to understand the effects on the improvement of hair texture, In the results of analyzing the absorbance with the use of methylene blue, the value after application was decreased than the value before application. In the results of measuring the gloss, none of the samples showed huge differences. In the results of this study, the milk thistle oil showed the effects on the texture improvement of damaged hair.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.9-18
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• 2021

This study was aimed to investigate the effects of hair dyeing and changes of hair quality by the application of indigo dye. Methods: Indigo dye was used after water bath. After application of the dye to healthy and bleached hair samples, they were treated with heat and remained naturally by different times. Each sample was measured before and after the application and compared for the analysis. To investigate the effects of dyeing, L⁎, a⁎, and b⁎ values and bleaching degree were measured using by color-difference meter. To understand the changes of hair quality, absorbance and gloss were measured using by tensile strength and methylene blue. Results: Upon the results of dyeing, all the samples showed the significant dyeing effects before and after the application in terms of L⁎, a⁎, and b⁎ values. With respect to the bleaching effects, it showed the greatest change on Day 1 and did not show any changes from Day 3. For the measurement of tensile strength, mean values of all the samples were increased. However, the results were not significant, statistically, demonstrating no change of hair quality. No statistically significant results were found in the samples except healthy 7L(3) sample upon the absorbance results using methylene blue. Gloss of samples was changed upon the statistical analysis results. Conclusion: Indigo dye showed the hair dyeing effects, significantly, while gloss was changed and tensile strength and absorbance were not changed in terms of hair quality. Further studies are required on the processing with a variety of dyes and on the measurements for reliability and objectivity.

• Journal of the Mineralogical Society of Korea
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• v.15 no.4
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• pp.259-272
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• 2002

This study was tried to interpret the important major factors controlling some physicochemical properties by comparing mineralogical and physicochemical characteristics such as pH, cation exchange capacity, Methylene Blue adsorption amount, swelling, viscosity, strength (compressional and tensile), and surface area etc. Investigated bentonite samples are five Korean samples from Dusan, Naa, Oksan, Dongyang, and Yeonil deposits and two Japanese bentonites from Tsukinuno and Tomioka deposits which were formed under a similar geological environment of the Tertiary basin. Tsukinuno bentonite is only natural Na-type bentonite and the others are all Ca-type bentonites. Most of the properties are not explained by the montmorillonite content only though the most important factor controlling the physicochemical properties is the montmorillonite content. The layer charge of montmorillonite will strongly control cation exchange capacity and Methylene Blue adsorption. Zeolite bearing bentonites show the strong alkaline character and causes the increase of cation exchange capacity, however decrease swelling, viscosity and strengths. Pyrite bearing bentonites decrease green compressional strength and wet tensile strength. The exchangeable interlayer cations control some physicochemical properties. Na-type bentonite than Ca-type shows more strong alkaline character and much more advanced swelling and viscosity. Also the size and thickness of montmorillonite flakes seem to control some physicochemical properties. Bentonite mainly composed of montmorillonite of very thin and large flakes is characterized by the very high surface area, cation exchange capacity, viscosity, swelling, Methylene Blue adsorption, green compressional strength and wet tensile strength. Domestic Dusan bentonite shows the most excellent physicochemical properties, which is due to the high content(84%) and very well crystallinity of montmorillonite.

• Analytical Science and Technology
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• v.28 no.1
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• pp.40-46
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• 2015

Hydrochar has been generated from food waste via hydrothermal carbonization (HTC) reaction. As a solid product of HTC reaction, hydrochar has a great potential as an adsorbent of pollutants from the various media. The surface area and pore volumes are very important parameters to be served as an adsorbent. It requires an expensive equipment and consumes time to measure those parameter. Therefore, titration methods including iodine and methylene blue adsorption were evaluated to be correlated with that of BET analysis. Even though the absolute values of the computed surface area and pore volumes were not able to be matched directly, the patterns of change were successfully correlated. Among the reaction conditions, the reaction time and temperature at $230^{\circ}C$ for 4 h was determined as an optimization condition, which confirmed by titration method and BET analysis. Titration method for surface area and pore volumes computed by combination of iodine and methylene blue adsorbing values would be a simple and fast way of determining the optimization condition for hydrochar as an adsorbent produced by HTC reaction.

• Journal of the Korean Applied Science and Technology
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• v.38 no.4
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• pp.986-993
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• 2021

This study was aimed to investigate the improvement effects of kelp extract on the damaged hair by manufacturing hair quality improving formulation adding kelp extract and applying that in the damaged hair. With respect to the study materials, the formulation was manufactured with different strengths of kelp extract including 0, 2, 4, and 6 grams, adding perm base material. The manufactured formulation was applied to the decolored sample hair of Level 8 and its effects were measured and compared before and after its application. Tensile strength, absorbance using methylene blue, and gloss were measured as the tools to show the improvement effects of hair quality. To check the reliability of the results, statistical analysis was performed. Tensile strength showed to be increased in the Level 8 samples applied by the formulations containing 4- and 6-gram strength. Absorbance using methylene blue showed to be decreased in all the samples after the application, based on the absorbance results before and after the application. No difference was found in all the samples on the gloss. In conclusion, this study revealed that kelp extract could improve the damaged hair. Further studies are required to check the improvement effects on the damaged hair with multiple types of extracts and study methods.