• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.353-354
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• 2006

This work describes the effect of binders, such as carboxymethylcellulose (CMC), CMC+Polytetrafluoroethylene (PTFE) and PTFE, on the electrochemical and mechanical properties of activated carbon-electrode for electric double layer capacitor. The cell capacitors using the electrode bound with binary binder composed of CMC and PTFE, especially m composition CMC ; PTFE = 60 : 40 wt %, has exhibited the better rate capability and the lower internal resistance than those of the cell capacitor with CMC. On the other hand, the sheet type electrode kneaded with PTFE was bonded with conductive adhesive on Al foil. This cell capacitor using the electrode with PTFE exhibited the best mechanical properties and rate capability compared to the CMC and CMC+PTFE one These behaviors could be explained by the well-developed network structure of PTFE fibrils during the kneading process.

• 한국토양비료학회지
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• 제36권2호
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• pp.86-91
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• 2003

흑연이나 활성탄등의 탄소물질이 작물의 생육을 촉진하며 유용 토양미생물의 생육을 촉진하는것으로 알려져 있어 본 실험에는 제철공정에서 재활용, 정제된 흑연을 상토의 첨가제로 시용하여 벼의 생육과 수량에 미치는 영향에 대하여 실험하였다. 실험결과, 이앙기의 생육은 대조구와 비교하여 0.1% 흑연 첨가구에서 생육 촉진효과가 보였으며 이앙후 처리구별 생육의 차이는 그다지 보이지 않았다. 다만 0.1% 첨가구에서 육묘한 벼의 수량은 특별한 통계적 유의성을 보이지 않았으나 약 1%정도 증수되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.116-119
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• 2002

A different route to the synthesis of $Eu^{3+}$ - activated matrices such as $YAlO_{3}$ and $GdAlO_{3}$ and luminiscent properties of these compounds, were studied. The new route (Combustion method) consist of the redox reactions between the respective metal nitrates and urea in a preheated furnace at ${500^{\circ}C}$. The Phosphor thus obtained were then heated at ${1000^{\circ}C}$ for 2-3 hours to get better luminiscent properties. The incorporation of $Eu^{3+}$ activator in these phosphors were checked by luminiscence investigations. Scanning electron microscopy (SEM) studies were carried out to understand surface morphological features and the particle size. X-ray energy dispersive analysis (EDAX) was also performed for the qualitative analysis of the phosphors.

• Restorative Dentistry and Endodontics
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• 제10권1호
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• pp.145-152
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• 1984

The purpose of this study was to compare combinations of the four visible light irradiating appliances (Translux, Heliomat, Pluraflex HL 150, Omega) and the four visible light activated composite resins (Durafil, Heliosit, Plurafil-super, Silux) to determine the depth of polymerization of each combination. Twenty samples were made with Durafil. Five samples were polymerized for 20 seconds using Translux, five with Heliomat, five with Pluraflex HL 150, five with Omega. Twenty samples were made with Heliosit, twenty with Plurafil-super, and twenty samples with Silux. A 20-second polymerization time was applied with each of 4 visible light irradiating appliances to 5 samples of each material. Eighty samples were treated in a like manner, but polymerization was extended to 40 seconds. Depth of polymerization were measured with caliper. The results were as follows. 1) Of the two time exposures, 40-second exposure provided a significantly greater depth of polymerization than 20-second for each light with each material. 2) Durafill-Translux system showed minimum depth of polymerization, and Plurafil-Pluraflex system showed maximum depth of polymerization. 3) Visible light irradiating appliances were able to harden the resins cured by tire visible lights of other makers' apparatuses. 4) In all circumstances, depth of polymerization was between 3.0-3.8mm.

• 한국분말재료학회지
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• 제26권2호
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• pp.107-111
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• 2019

The activation energy to create a phase transformation or for the reaction to move to the next stage in the milling process can be calculated from the slop of the DSC plot, obtained at the various heating rates for mechanically activated Al-Ni alloy systems by using Kissinger's equation. The mechanically activated material has been called "the driven material" as it creates new phases or intermetallic compounds of AlNi in Al-Ni alloy systems. The reaction time for phase transformation by milling can be calculated using the activation energy obtained from the above mentioned method and from the real required energy. The real required energy (activation energy) could be calculated by subtracting the loss energy from the total input energy (calculated input energy from electric motor). The loss energy and real required energy divided by the reaction time are considered the "metabolic energy" and "the effective input energy", respectively. The milling time for phase transformation at other Al-Co alloy systems from the calculated data of Al-Ni systems can be predicted accordingly.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.172-173
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• 2019

As the damage to fine dust increased, the Republic of Korea designated fine dust as a social disaster. The composition of the fine dust is composed of carbon, sulfate, nitrate, ammonium and minerals. The cause of fine dust is naturally generated by dirt, pollen, etc. In addition, there are artificial causes such as gaseous vehicle exhaust gas emitted from the use of fossil fuel. When fine dust enters the human body through breathing, it causes various respiratory diseases and skin diseases. In IARC, fine dust was designated as a carcinogen group 1. In this research, we tried to adsorb fine dust by physical adsorption using powdered activate carbon. Powdered activate carbon is a powdered activated carbon activated in a carbonized state. Porous material with high specific surface area and low density. Experimental items were tested for density, water absorption, and fine dust concentration according to the PAC addition ratio. Basic experiments were carried out to fabricate the fine dust adsorption matrix.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1630-1636
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• 2009

Nine alkali-activated (AA) mortars were mixed and cured at water or air-dried conditions to explore the significance and limitation for the application of the combination of Ba and Ca ions as an alkali-activator. Ground granulated blast-furnace slag (GGBS) was used for source materials, and calcium hydroxide (Ca(OH)₂) and barium hydroxide (Ba(OH)₂) were employed as alkali activators. Test results clearly showed that the water curing condition was more effective than the air-dried curing condition for the formation of the denser calcium silicate hydrate (C-S-H) gels that had a higher molar Si/Ca ratio, resulting in a higher strength development. At the same time, the introduction of Ba(OH)₂ led to the formation of 2CaO·Al₂O₃·SiO₂·8H₂O (C₂ASH₈) hydrates with higher molar Si/Al and Ca/Al ratios. Based on the test results, it can be concluded that the developed cementless mortars have highly effective performance and high potential as an eco-friendly sustainable building material.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.77-78
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• 2020

An alkaline activator was synthesized by dissolving waste glass powder (WGP) in NaOH-4M solution to explore its effects on the Class-C fly ash (FA) and ground granulated blast furnace slag (GGBS) based alkali-activated material (AAM). The compressive strength and porosity were measured, and (SEM-EDX) were used to study the hydration mechanism and microstructure. Results indicated that the composition of alkali solutions was significant in enhancing the properties of the obtained AAM. As the amount of dissolved WGP increased in alkaline solution, the silicon concentration increased, causing the accelerated reactivity of FA/GGBS to develop Ca-based hydrate gel as the main reaction product in the system, thereby increasing the strength. Further increase in WGP dissolution led to strength loss, which were believed to be due to the excessive water demand of FA/GGBS composites to achieve optimum mixing consistency. Increasing the GGBS proportion in a composite also appeared to improve the strength which contributed to develop C-S-H-type hydration.

• 한국건설순환자원학회논문집
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• 제7권4호
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• pp.104-112
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• 2012

플라이애시의 주요 성분은 $SiO_2$, $Al_2O_3$, $Fe_2O_3$로서 이들 세 성분이 전체의 80~90%를 차지한다. 최근 알칼리 자극제를 활용하여 플라이애시를 활성화하여 제조한 결합재에 대한 연구가 활발하게 진행되고 있다. 알칼리 활성화 반응에 의한 결합재는 시멘트 수화생성물인 C-S-H와 수산화칼슘을 형성하지 않으므로 $500^{\circ}C$이상에서도 현저한 강도저하 현상이 발생하지 않기 때문에 효율적인 내화성 마감재를 제조할 수 있다. 본 연구는 플라이애시를 활용하여 알칼리 활성화 결합재를 제조하고 고온에서의 내부구조 분석을 통하여 고온에서 안정한 재료임을 확인하고 내화성 마감재로의 적용에 대한 효용성을 확인할 수 있었다.

• 대한환경공학회지
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• 제30권1호
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• pp.61-68
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• 2008

알칼리활성 플라이 애쉬 시멘트(AAFC)라 불리는 새로운 시멘트 물질을 이용하여 AAFC-콘크리트를 제조하였다. 알칼리활성 플라이 애쉬 시멘트를 사용하여 제조한 AAFC-콘크리트와 OPC-콘크리트에 대하여 산 침투, 염분, 탄산화, 동결 융해에 대한 영향과 SEM, XRD 분석을 수행하였다. 플라이 애쉬를 85$^{\circ}C$에서 24시간 동안 알칼리 활성화하여 제조한 AAFC-콘크리트(35 MPa)의 산 저항성은 OPC-콘크리트(35 MPa)보다 훨씬 뛰어난 것으로 나타났다. 또한 AAFC-콘크리트(35 MPa)는 염분용액, 탄산화 그리고 동결-융해와 같은 공격에 OPC-콘크리트(35 MPa)와 비슷한 저항성을 가지고 있는 것으로 나타났다.