• 한국세라믹학회지
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• 제43권7호
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• pp.393-401
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• 2006

The development of Korean glaze originated from the development of ash glazes. Ash not only has strong solubility but also can shows the glaze a variety of different colors according to what the glaze has in it as the main component. In addition, it gives a feeling of lucidness and softness. For these reasons, there are a lot of needs for ash and many potters want to take advantage of ashes as glaze. But natural ashes have not been widely used as glaze primarily because it is relatively hard to find or manufacture. Considering the difficulty of finding or manufacturing natural ashes, this study aims to formulate synthetic ash which not only is available to the potters in general but also has the sam ε characteristics as the natural ashes. To achieve this aim, this study examines the characteristics of the pine tree ash, the main component of the glaze of celadon porcelains, and the red pepper stem ash, the main component of the brown glaze, both of which have been used by the Korean traditional potters. In this study, the alkaline component of the glaze. A important ingredient when the ashes are synthesized, was supplied by mixing of $Na_2CO_3$, Chungju limestone and rice straw ash. Furthermore, the synthetic ash, when it shows no change of pH in its composition rate of 6:2:2, was found to be usable as the most stable material. In conclusion, the formula which frits some raw $materials-Na_2CO_3$, Chungju limestone and rice straw ash-can duplicate the synthetic ash which is simila to the natural ash.

• 자원리싸이클링
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• 제10권5호
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• pp.36-43
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• 2001

The chlorine component in fly ash from municipal solid waste incineration ash was removed by water washing for the purpose of recycling fly ash as a raw material of ordinary portland cement. The samples were a different kind of 리y ashes using $Ca(OH)_2$and NaOH as media of wet scrubber for flue gas cleaning. The content of soluble salts of fly ash using $Ca(OH)_2$and NaOH was 32.8%, 50.1% and the content of chlorine component, 22.9% and 26.0% respectively, which was KCl, NaCl, CaC1OH mainly. When each fly ash was washed using water under conditions of a agitation speed of 300 rpm, a liquid to solid ratio of 10, most soluble salts in fly ash were dissolved within 30 minutes and the content of chlorine component in ash was diminished to the content of 4.4%, 2.O% at $20^{\circ}C$ and 1.7%, 0.8% at $50^{\circ}C$ respectively. And the main compound of residual chlorine component in ash after water washing was friedel`s salt ($3CaO.A1_2$$O_3$.$CaCl_2$.$10H2$O). From analysis results of water quality for wastewater by water washing, the components exceeding discharged wastewater standard were only Pb and Cd. But As pH was controlled to 10 with addition of $CO_2$(g) or $Na_2$$_CO3$in water, the concentration of heavy metals such as Pb and Cd was also under discharged wastewater standard.

• 한국세라믹학회지
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• 제49권2호
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• pp.185-190
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• 2012

The purpose of this study was to examine a possibility that fly ash could be used as raw material for carbonation by conducting the experiment on magnetic separation and hydration of fly ash that contained a large amount of CaO composite. Wet magnetic separation experiment was performed to remove the component of magnetic substance that contained fly ash, which aimed at increasing the content of CaO in the non-magnetic domain. The selected fly ash was used for hydration experiment before the TG-DTA, XRF and XRD analyses were made to confirm the Ca component that could be carbonated. Then, the fly ash was turned to a hydrate that was favorable to dissociation of $Ca^{2+}$ ion. As a result, the magnetic separation enabled detecting the content of CaO component by up to 61 wt% in the non-magnetic domain. Since the hydrate was confirmed, it is believed that the fly ash can be used as raw material for carbonation.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.176-177
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• 2021

In order to compensate for the defects of concrete made using only Portland cement, three-component powder mixed with blast slag and fly ash, and four-component powder concrete mixed with silica fume are being produced. When each of the admixtures is used alone, the above-described excellent performance is expressed and up to 70% of the powder is used. These technologies are also contributing to the reduction of greenhouse gases under Act on Low Carbon. Green Growth. However, calcium hydroxide is consumed as a stimulator or reaction in the case of silica fume, which causes latent hydroponicity of slag, pozzolane reaction, and silica mixtures represented by fly ash. It is known that the consumption of calcium hydroxide affects the alkalinity of concrete. As a result, the carbonation resistance is significantly lower among the durability of concrete. Research on quantification of such effects is insufficient. In this study, an experiment was conducted to quantify calcium hydroxide of the three-component and four-component powder paste using thermal analysis equipment (DTG), and the effect of the mixing amount was discussed.

• Korean Chemical Engineering Research
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• 제52권2호
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• pp.233-239
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• 2014

석탄 연소 시 발생하는 회가 보일러 벽면에 부착되어 일어나는 슬래깅 현상은 보일러의 열효율을 감소시키고 보일러 안정성에도 악영향을 준다. 이러한 슬래그의 유동 특성은 회의 용융 특성과 관련이 있는데 이는 회의 화학적 조성에 영향을 받는다. 본 연구에서는 회의 용융특성을 TMA(Thermo-Mechanical Analysis) 장비를 이용하여 분석하였다. 이 테스트는 회의 수축률에 따른 용융온도(T25%, T50%, T75%, T90%)를 정량적으로 측정 하는 방법이다. TMA에서 측정된 각각의 온도는 용융단계별 특성을 나타낸다. TMA로 분석된 결과 값에 XRF 장비를 이용하여 분석한 회의 성분 조성이 미치는 영향을 분석하였다. 회에 포함된 성분 중 refractory, fluxing contents가 회분의 용융온도에 미치는 영향을 확인할 수 있었다. Refractory contents 성분인 $SiO_2$, $Al_2O_3$의 함량이 많을수록 전체적인 용융온도가 올라가며 $SiO_2/Al_2O_3$가 커질수록 고온에서의 용융온도인 T75%, T90%가 낮아지는 것을 알 수 있었다. 이와 달리 fluxing contents 성분인 $Fe_2O_3$, $K_2O$, CaO의 함량이 많아질수록 전체적인 용융온도가 낮아지며 이중 $K_2O$, CaO는 초기 용융 온도인 T25%를 낮추는데 큰 역할을 하는 것으로 판단되었다. TMA 분석과 회의 조성 비교를 통하여 회의 용융 특성을 예측하고 설명할 수 있었다.

• 농업과학연구
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• 제3권1호
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• pp.53-60
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• 1976

연탄재의 삽목용토(揷木用土)로서의 이용가능성(利用可能性)을 조사(調査)하기 위해 연탄재 모래 및 Vermiculite를 몇가지 비율(比率)로 혼합(混合)한 용토(用土)를 사용하여 삽수(揷穗)의 발근(發根)에 미치는 영향(影響)을 조사(調査)하고 아울러 연탄재를 삽목용토(揷木用土)로 사용할 때 가장 적당한 용토(用土)의 준비방법을 구명(究明)하기 위하여 입자(粒子)의 크기를 몇가지 종류(種類)로 구분(區分)하여 삽수(揷穗)의 발근(發根)에 미치는 영향(影響)을 조사(調査)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 연탄재는 단용(單用)으로도 모래에 비하여 우수한 발근용토(發根用土)로 생각되며 타용토(他用土)와 혼합(混合)해서 사용하면 더욱 효과적(效果的)이다. 2. 연탄재를 삽목용토(揷木用土)로 사용할 경우 입자(粒子)의 크기는 2~3mm의 것이 가장 좋다고 생각된다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.616-620
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• 2001

The objectives of this study are to investigate the suitability of various coal fly ashes and incineration ashes for zeolite synthesis. Zeolite P and hydroxysodalite are produced from coal fly ash and paper sludge incineration ash. When soluble and acid-soluble materials in incineration fly ash are removed by the water washing or acid washing before hydrothermal synthesis, hydroxysodalite can be produced. The factors to make solid-liquid separation difficult are the calcium component and the unburned carbon in ash.

• 한국세라믹학회지
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• 제35권2호
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• pp.180-184
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• 1998

It was examined that the rheological behaviors of fly ash 70wt%-clay 30wt% slip in which nonplastic fly ash was a major component. We have systematically investigated the effects of deflocculant(Tetrasodium pyrophosphate ; Na4P2O7 nH2O Sodium silicate; Na2SiO3) and coagulant(CaSO4) on the rheological behavior of ash-clay slip. Ash-clay slip have been characterized on the basis of the time dependent rheology which was done out by the gel-curve test. Dispersion mechanism of ash-clay slip is the steric stabilization by the Na2SiO3 coating of cenospheres surface. Coagulated slip seems to have the new network structure and shows the gellation behaviors which makes it possible to direct coagulated casting(DCC).

• Journal of Forest and Environmental Science
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• 제25권2호
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• pp.127-130
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• 2009

This study has been carried out to investigate the characteristics of the commercial wood pellets such as moisture content, heating value, ash content, and chemical component. The wood pellets from national forestry cooperatives federation and China were evaluated to see if they can be 1st or 2nd class of Korea standard. Indonesian pellet was estimated to be a 3rd class because of the heating value and high ash content. It is considered that there is a quality difference in wood pellets in accordance with the production nations. It could be originated from the difference of raw materials produced in different region.

• 농업과학연구
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• 제47권1호
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• pp.67-81
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• 2020

The physicochemical parameters of honey are used to determine the botanic origin of honey and to specify the composition criteria for honey in regulations and standards. The parameters of honeydew and blossom honeys from Korean beekeepers were determined to investigate whether they complied with the composition criteria for honey in the food code legislated by Korean authority and to establish the parameters which should be subjected to principal component analysis for improved differentiation of honeys. The fructose and glucose contents of the honeydew honey did not comply with the composition criteria. The ash content of the honey was closely correlated with CIE a^* and CIE L^* The principal component analysis of fructose to glucose ratio, CIE a^*, CIE L^*, ash content, free acidity, and fructose and glucose contents enabled classification of honeydew, chestnut, multifloral, and acacia honeys. Additional advantage of the principal component analysis (PCA) is that the physicochemical parameters, such as fructose to glucose ratio (F/G) and color, can be determined using the analytical instruments for composition criteria and quality control of honey. This study suggested that composition criteria for honeydew honey should be established in the food code in accordance with international standards. The principal component analysis reported in this study resulted in improved classification of the honeys from Korean beekeepers.