• Elastomers and Composites
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• v.48 no.1
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• pp.67-75
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• 2013

E-TPE (Engineering Thermoplastic Polyether Ester) was Ester Elastomer with functional groups as recycling and fast processability. In addition, if the car's lightweight enough to highlight eco-friendly materials that help to improve fuel economy has become. Have all the attributes of the rubber and engineering plastics E-TPE the available temperature area is spacious, heat resistance and oil resistance is excellent but getting attention as a new material in the field of auto parts in the field of electrical and electronic domestic depends entirely on imports by the lack of core technology and has been research and development is urgently needed. In this study, the hard segments, polyester (TPEE) as the base soft elastomers of the segments Ethylen-prophylene-Copolymer and CSM (Choloro sulphonated polyethylene Rubber), VAMAC (Ethylene Acrylic Rubber), NBR (Acrylonitrin Butadiene Rubber), 1, 3-Phenylene-bisoxazoline is dealing with Dynamic Vulcanized by content and added rubber properties, thermal variation observed. As a result, the properties of the dynamic vulcanization with NBR compared to other rubber heat resistance and oil resistance is on the increase.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.1
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• pp.103-110
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• 2010

Recently, reducing usage of cement and using by-product of industry such as blast furnace slag and fly-ash have been increased to reduce $CO_2$ gas emission. That apply to construction. As a result, reduction of environmental stress and recycling of resources are expected. In this study, as basic study to the reuse of resources and reduce Environmental Load, comparing and analyzing hardening characteristics and durability as using the blast furnace slag and fly-ash, examining concrete characteristics substituted the three elements for the blast furnace slag and fly-ash and evaluating the relationship as binder. Through this, it want to provide the basic data for mass utilization. Blast furnace slag powder and replaced at fly-ash compressive strength of concrete in the strength of the initial seven days material age lower level of expression significantly compared to the concrete, but, 28 days after the similar or higher compressive strength than the concrete expression of the was. In addition, the reserves replacement of blast furnace slag powder salt injury increasing resistance are seen improvements, according to the conventional blast furnace slag powder study by the chloride ions on the surface of the concrete are improved being fixation salt injury resistance is considered.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.103-106
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• 2014

Recycling of bottom ash from municipal solid waste (MSW) incinerator has been strictly limited due to its composition of high level chlorine and other unfavorable substances. The composition of MSW has been, however, changed after the introduction of garbage-bag sales system, extended producer responsibility (EPR) policy and the prohibition of direct landfill of food waste. Recent waste shows reduced moisture and chlorine content, increased calorific value due to the separation of food waste, incombustible materials and PVC. The main purpose of this study is to investigate the trend of composition changes of MSW incinerator bottom ash and to compare the analytical results with those before the separation system was introduced. CaO content of bottom ash, one of the major component of cement clinker, increased from 26.7% in 2001 to 34.0% in 2006. The chlorine content showed a dramatic decrease from 1.84% in 2001 to 0.00655% in 2006, which is closely compatible with that of the fly ash of coal-utilizing thermal power plants, which is mainly due to the changes of MSW composition. It is eventually considered that there is a possibility of utilizing the incinerator bottom ash as a raw material of cement clinker feed substances.

• Herbal Formula Science
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• v.29 no.4
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• pp.239-252
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• 2021

Objectives : This study is to effect of improving muscle atrophy through water extract on the solid-phase fermentation extraction with Phellinus linteus of discarded Schisandra chinensis in an atorvastatin-induced atrophy C2C12 cell. Methods : C2C12 myoblast were differentiated into myotube by 2% horse serum medium for 6 days, and then treated solid-phase fermentation(S-P) extract at different concentrations for 24h. To investigate the effect of S-P extract on the induction of muscle atrophy and expression of atrophy-related genes and apoptosis in differentiated C2C12 myotubes using a GSH, ROS, real-time PCR, western blots analysis. Results : As a result of treatment with atorvastatin at concentrations of 5, 10, and 20 uM on the 6th day of differentiation in C2C12 myotube cells, it was confirmed that the cell morphology was damaged in a concentration-dependent manner, and the length and thickness of the myotube also decreased in a concentration-dependent manner. Treatment with S-P extract (50, 100 and 200 ㎍/㎖) increased of GSH and inhibited ROS in the atorvastatin-induced muscle atrophy cell model at a concentration that did not induce toxicity. In addition, it was confirmed that it has an effect on muscle reduction by inhibiting apoptosis of muscle cells as well as being involved in protein production and degradation of muscle cells. Conclusions : Atorvastatin-induced atrophy C2C12 cell, S-P extract activates related to differentiation/generation and proteolysis, and inhibits cell death of atrophy in C2C12 cell. Based on this, it is necessary to prove its effectiveness through animal models and human application test, but it is considered to be discarded Schisandra chinensis can present the potential for development as a recycling industrial material.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.253-259
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• 2021

Plastic wastes generated from household waste are separated by mixed discharge with foreign substances, and recycling is relatively low. In this study, the effect of the ratio and content of mixed plastic waste coarse aggregate(MPWCA)s and mixed plastic waste fine aggregate(MPWFA)s filled with blast furnace slag fine powder on the slump and compressive strength of concrete was evaluated experimentally. The MPWCAs were found to have a similar fineness modulus, but have a single particle size distribution with a smaller particle size compared to coarse aggregates. However, the MPWFAs were found to have a single particle size distribution with a larger fineness modulus and particle size compared to fine aggregates. Meanwhile, the effect of improving the density and filling pores by the blast furnace slag fine power was found to be greater in the MPWFA compared to the MPWCA. As the amount of the mixed plastic waste aggregate(MPWA)s increased, the slump and compressive strength of concrete decreased. In particular, the lower the slump and compressive strength of concrete was found to decrease the greater the amount of MPWFA than MPWCA when the amount of MPWA was the same. This is because of the entrapped air and voids formed under the angular- and ROD-shaped aggregates among the MPWFAs. On the other hand, the addition of the admixture and the increase in the unit amount of cement were found to be effective in improving the compressive strength of the concrete with MPWAs.

• International Area Studies Review
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• v.15 no.3
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• pp.513-532
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• 2011

Green supply chain management(GSCM) has emerged as a key approach for firms seeking to become sustainable environmentally. GSCM is a system in which the firm takes life cycle responsibility of the products through material recycling, environment-friendly production, and reverse logistics in addition to the classical operations in a supply chain. This paper endeavors to identify the relationship between the GSCM practice implementation and firms' performance among a sample of Korean manufacturing firms. Based on a literature review, eight hypotheses are put forward. First of all, a factor analysis was conducted to derive groupings of GSCM practice from the survey data which included 54 responses. Then, the first regression was conducted to examine the link between GSCM practice implementation and firms' financial performance. The result shows that green purchasing and green production are significant. The second regression was conducted to examine the impact of GSCM practice implementation on the firms' competitiveness. The result reveals that green purchasing, green production, and reverse logistics are positively signifiant.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.267-274
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• 2018

Though the wet bottom ash has been used as a type of lightweight aggregate, dry bottom ash, new type bottom ash from coal combustion power plant, has scarcely researched. It is excellent lightweight aggregate in the view point of construction material. This study is performed to check the applicability of dry bottom ash as a fine aggregate in lightweight aggregate concrete, by analyzing various properties of fresh and hardened concrete. We get results that the slump of concrete is within the target range at less than 75% replacement rate of dry bottom ash, the air content is not affected by the replacement rate of dry bottom ash, the bleeding capacity is less than $0.025cm^3/cm^2$ at 75% under of the replacement rate of dry bottom ash, and the compressive strength of concrete show 90% or more comparing the base mix while initial strength development is a little low. Oven dry unit weight of concrete is reduced by 8.9% when replaced 100% dry bottom ash, and dry shrinkage tends to decrease depending on increase of replacement rate of dry bottom ash. Modulus of elasticity of concrete shows no decease at 50% over of the replacement rate of dry bottom ash, while modulus of elasticity of concrete decreases when the replacement rate increases further. The dry bottom ash, when used as a fine aggregate in lightweight concrete, can be used effectively without any deterioration in quality.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.2
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• pp.141-150
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• 2019

The purpose of this study is to investigate the effect of the pre-service teacher's maker project learning on self -directed learning ability and creative personality. This study established an eight-week period of experimental treatment from March to April 2019, and the students who participated in the study formed a research group of 75 students in three of their advanced classes who are attending the second semester of B University of Education and taking courses in 'Teaching Research 1'. The experimental treatment of research groups was conducted by the process of producing creative outputs through training of manufacturers. The experimental group of the study group was a process of producing creative output through maker education. The theme was set up to create creative output by group, worked with the main tool, 3D pen, and utilized the recycling material. When the creative output is completed, it is announced by presenting the actual product in each group. The results of the study are as follows. First, project learning by pre-service teachers had an effect on self-directed learning ability. Second, project learning by pre-service teachers had an effect on creative personality. Third, pre-service teachers was interested in learning about the project and responded positively to the students' perception.

• Journal of the Korean GEO-environmental Society
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• v.12 no.7
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• pp.23-29
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• 2011

The oxidation slag has been widely used in civil engineering project, whereas the reduced slag from electric furnace has yet to be applied. Consequently in order to find out the recycling method in civil engineering field, the mineral compositions of the reduced slag were analyzed and some tests on water quality were performed to estimate the potential release of toxic compounds. Slag-soil mixtures of 0, 10, 20 and 30%(dry weight) soil were prepared in lysimeter columns and the effluents were collected with the period of one, two and four week options in closed system, respectively. The result from qualitative and quantitative analysis using X-ray Diffraction(XRD) and X-ray Fluorescence(XRF) indicates that the main mineral of the reduced slag is $Ca_2(SiO_4)$, a kind of calcium silicate. Also, the leaching medium analyzed by Inductively Coupled Plasma Optical Emission Spectroscopy(ICP-OES) showed that main heavy metals such as Al, Fe and Mn are included in the reduced slag due to the effect of steel production process. It can be seen that the leachate does not violate the regulation guide line of waste material of heavy metal. Also the pH levels were increased from pH 6.9 for 0% soil to pH 10 for 30% soil. However the influence on leachate circulation period of one through four weeks was negligible.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3250-3259
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• 2022

A new approach to the use of rice straw as a difficult-to-recycle agricultural waste was proposed. Potassium aluminosilicate was obtained by spark plasma sintering as an effective material for subsequent immobilization of ¹³⁷Cs into a solid-state matrix. The sorption properties of potassium aluminosilicate to ¹³⁷Cs from aqueous solutions were studied. The effect of the synthesis temperature on the phase composition, microstructure, and rate of cesium leaching from samples obtained at 800-1000 ℃ and a pressure of 25 MPa was investigated. It was shown that the positive dynamics of compaction was characteristic of glass ceramics throughout the sintering. Glass ceramics RS-(K,Cs)AlSi₃O₈ obtained by the SPS method at 1000 ℃ for 5 min was characterized by a high density of ~2.62 g/cm³, Vickers hardness ~ 2.1 GPa, compressive strength ~231.3 MPa and the rate of cesium ions leaching of ~1.37 × 10^-7 g cm^-2·day^-1. The proposed approach makes it possible to safe dispose of rice straw and reduce emissions into the atmosphere of microdisperse amorphous silica, which is formed during its combustion and causes respiratory diseases, including cancer. In addition, the obtained is perspective to solve the problem of recycling long-lived ¹³⁷Cs radionuclides formed during the operation of nuclear power plants into solid-state matrices.