• 한국세라믹학회지
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• 제26권2호
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• pp.167-170
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• 1989

Al2O3/SiC composite-material was synthesized by the birth-spread mechanism through the carbothermal reduction reaction of SiO2 in Ha-Dong Kaolin with carbon powder under H2 gas atmosphere at 1300~140$0^{\circ}C$. Average diameter of synthesized SiC whiskers were 1${\mu}{\textrm}{m}$ and aspect ratio (c/a) was 10~100. Al2O3 particles and SiC whiskers were mixed homogeneously in the reacted pellet.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.79-80
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• 2018

Recently, the interest in remodeling of new and old buildings is increasing worldwide. As a result, the frequency of use of architectural adhesives has increased. Currently, adhesives used in buildings are made of organic materials in most cases, and epoxy resin adhesives are most widely used. However, epoxy resin adhesives contain formaldehyde and VOCs in the room during construction, which can cause sick house syndrome. In case of building fire, it may cause damage due to carbon monoxide generated from organic materials. It is urgent to study the problem of epoxy fill adhesive made of such organic materials. Therefore, the purpose of this study is to investigate the effect of the adhesion of epoxy resin adhesive, which is a problem of epoxy resin adhesive, which is an existing organic adhesive by using inorganic materials such as magnesia and phosphate, And the inorganic adhesive which does not emit the release amount as an inorganic material.

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.1919-1924
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• 2012

Poly(anthranilic acid) was synthesized by rapid mixing method using 5-sulphosalicylic acid as a dopant. The synthesized polymer was characterized by various techniques like FT-IR, UV-Visible, and X-ray diffraction $etc.$, The FT-IR studies reveal that the 5-sulphosalicylic acid is well doped within the polymer. The morphological property was characterized by field emission scanning electron microscopic technique. The electrochemical properties of the polymer were studied by cyclic voltammetric method. The synthesized polymer was used to modify glassy carbon electrode (GCE) and the modified electrode was found to exhibit electrocatalytic activity for the oxidation of uric acid (UA).

• 분석과학
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• 제6권3호
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• pp.297-305
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• 1993

글로우 방전 방출원을 다색화장치에 연결시켜 개발된 글로우방전/방출분광법으로 탄소의 농도가 수 퍼센트에 이르러 스파크방출분광법으로서는 분석이 곤란한 주철시료를 분석하고 정확성을 검토하고자 하였다. 알곤가스 압력, 전압, 방전시간 등 glow discharge lamp(GDL)의 방전조건을 최적화시키고 이 조건에서 두 종류의 주철 표준시료(BAS, LECO)에 대해 원소별 방출 복사선의 세기와 농도의 상관관계를 조사하였다. Mn, Si, P, S 등 대부분 원소의 검정곡선이 양호한 직선성을 보여 주었고 탄소의 경우에는 표준시료의 종류에 따라 절편과 기울기값이 미소하게 계통적인 차이를 나타내었다.

• 환경영향평가
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• 제32권5호
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• pp.353-362
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• 2023

TOC는 수중에 있는 유기물질의 90% 이상을 측정할 수 있으며 신속하고 용이하게 측정할 수 있기 때문에 기존에 사용된 유기오염물질의 지표인 BOD와 COD를 대체하고 있다. 수질오염공정시험기준에 따라 TOC를 측정할 때, 시료의 총탄소 중 무기탄소 비율이 50% 이상일 경우 NPOC법으로 분석하고, 휘발성유기화합물이 수 mg/L 이상일 경우 가감(TC-IC)법으로 분석하도록 규정되어 있다. 이러한 분석조건의 제한성을 검증하기 위해 정제수에 총유기탄소와 무기성 탄소의 비율이 다르게 하여 시험용액에서 총유기 탄소 농도결과를 확인하였는데 가감법과 NPOC법에서 큰 차이가 나타나지 않았다. 휘발성유기화합물 표준 용액을 첨가한 시료를 측정한 결과, NPOC법으로 분석할 때에 퍼징으로 인해 유실되는 탄소량은 크지 않은 것으로 나타나 시료에 휘발성유기화합물이 존재 시 분석방법에 따른 차이는 크지 않은 것으로 판단된다. 수질오염공정시험기준과 환경측정기기의 형식승인·정도검사 등에 관한 고시의 기준에 의한 판정 결과가 달라지는 경우를 판단하기 위해 국내에서 널리 사용하고 있는 2종류의 총유기탄소분석기의 현장시료 농도값 차를 비교한 결과, 제조사에 따라 NPOC법과 가감법에서 0.02~0.83 mg/L 차이가 있었으며, 이에 따라 기기 선정시 주의가 필요할 것으로 판단되었다.

• Carbon letters
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• 제9권2호
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• pp.137-144
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• 2008

The commercial activated carbons are typically prepared by activation from coconut shell char or coal char containing lots of inorganic impurities. They also have pore structure and pore size distribution depending on nanostructure of precursor materials. In this study, two types of commercial activated carbons were applied for EDLC electrode by removing impurities with acid treatments, and controlling pore size distribution and contents of functional group with heat treatment. The effect of the surface functional groups on electrochemical performance of the activated carbon electrodes was investigated. The initial gravimetric and volumetric capacitance of coconut based activated carbon electrode which was acid treated by $HNO_3$ and then heat treated at $800^{\circ}C$ were 90 F/g and 42 F/cc respectively showing 94% of charge-discharge efficiency. Such a good electrochemical performance can be possibly applied to the medium capacitance of EDLC.

• 한국환경보건학회지
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• 제14권2호
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• pp.65-71
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• 1988

In this study, the method of adsorption by activated carbon in the removal of Hg(II) ion in waste water was treated. The influence of kinds of activated carbon and effect of temperature and the influence of coexistent salt on adsorption rates, the influence of pH in the adsorption, equilibrium and adsorption of mercury from activated carbon were investigated. From the adsorption on activated carbon of mercury(II) ion in the presence of cyanide or thiocyanate ion was found that mercury(II) was easily adsorved onto the activated carbon in the form of complex artion such as Hg(CN)$_4^{2-}$, Hg(SCN)$_4^{2-}$ respectively. ZnCl$_2$ activation method had a higher adsorptive ability than steam activation method in adsorption of Hg on activated carbon. Activated carbon adsorbed iodide ion is very effective on adsorption of Hg.

• 한국유기농업학회지
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• 제5권1호
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• pp.87-99
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• 1996

Cultural conditions for mass production of the antagonistic bacteria, Bacillus subtills CAP134 against pathogens causing major airborne diseases to apple tree, effect of temperature, pH, carbon and nitrogen source in the culture broth were investigated. The bacterial growth was most vigorous when the temperature and pH of the culture broth was 30~$35^{\circ}$C, and 7, respectively. As for carbon source, dextrose was best followed in order by dextrose(monosaccharides)>sucrose(disaccharides)$\geq$saccharose(di-saccharides)>starch (polysaccharides). Among different sugars, bacterial growth was favored by in the order of brown, black and white sugars, indicating that the bacterial growth might be promoted by the minor elements presented as impurities in the less purified sugars. As for nitrogen source, organic forms were better to bacterial growth than inorganic forms, that is polypeptone was best followed in order by soy sauce, soybeen milk and inoganic nitrogens. Differences in bacterial growth among different forms of inorganic nitrogen were negligible.

• 한국재료학회지
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• 제7권11호
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• pp.1018-1023
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• 1997

본 연구에서는 3C-SiC의 ohmic 접합에 대하여 그 전기적 특성과 미세구조의 상관관계에 대하여 분석하였다. 표준사진식각 공정을 통하여 ohmic접합 금속으로서 Ni을 진공증착시켜 일련의 TLM패턴으로 열처리에 따르는 전류-전압 특성을 조사하였고 TEM, SEM, AES, EDS를 사용하여 Ni/SiC 계면에 대한 미세구조, 화학적 특성을 분석하였다. 열처리 온도와 시간을 통한 thermal budget이 증가함에 따라서 접촉저항이 감소되었으며 그 값은 $10^{-2}$-$10^{-4}$Ω$\textrm{cm}^2$의 범위에 속하였다. EDS와 AES를 통하여 7$50^{\circ}C$이상의 열처리 후 silicide(NiSi$_{2}$)의 주변에 carbon층이 형성되는 것을 확인하였으며, 열처리 온도가 증가함에 따라서 island형 silicide의 크기가 조밀해지며 SiC와의 접착성이 향상됨을 알 수 있었다. Ni/3C-SiC ohmic 접합의 전기적 특성은 계면에 생성되는 silicide와 carbon의 형성거동에 의하여 결정되는 것으로 믿어진다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.89-90
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• 2012

This study analyzed and compared the flowing and strength properties of mortar depending on the different fine aggregate replacement ratios and whether or not the mixing of PVA fiber was applied. blast furnace slag, red mud, and silica fume that are industrial by-products were used for the analysis. The findings showed that higher replacement level of fine aggregate increased air content while decreasing the table flow. In addition, in case of the compressive strength, Plain mortar and PVA fiber with the replacement ratios of 15% and 30%, respectively showed the greatest strength development.