• 한국산학기술학회논문지
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• 제14권3호
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• pp.1527-1532
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• 2013

본 휘발성유기화합물인 아세트알데하이드와 MEK(methylethylketone)의 광촉매분해특성을 회분식 광반응기를 이용하여 연구하였다. 광촉매분해반응의 주요 반응변수인 아세트알데하이드와 MEK의 초기농도, 수분함량, 그리고 반응온도의 영향을 조사하였다. 아세트알데하이드와 MEK의 광촉매 분해속도에서 어느 일정농도까지는 초기농도가 증가할수록 증가하나, 그 이상에서는 완만한 증가형태를 보이며, 분해반응형태는 Langmuir-Hinselwood 모델이었다. 아세트알데하이드와 MEK의 광분해반응에 있어 수분은 inhibitor 역할을 수행하였다. 그리고 아세트알데하이드와 MEK 분해반응에 있어 최적의 반응온도는 $45^{\circ}C$이었다.

• 한국염색가공학회지
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• 제18권6호
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• pp.37-42
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• 2006

Researches to preserve and restore the remaining fabrics as costume heritages have been carried out. In this study, in order to artificially restore an excavated silk fabrics, degummed silk fabrics and safflower dyed silk fabrics were prepared for an experiment. These fabrics were photo-degraded by the Xenon arc beam to have various strength retention(100%, 80%, 60%, 40%, 20%). The fine structure and physical properties of Xenon arc treated fabrics were investigated with various techniques such as tensile test, weight loss, wide-angle X-ray diffraction, yellowness, color, SEM etc. Tensile strength and the crystal diffraction intensity of silk fabrics decreased as Xenon arc hem treatment time increased. Weight loss increased slightly. Strength retention was decreased as the Xenon arc beam treatment time goes by. (Yellowness of the undyed silk fabrics and $L^*$ of the dyed silk fabrics increased. Whiteness of the undyed silk fabrics and $b^* of the dyed silk fabrics decreased.) SEM results of the silk fabrics treated Xenon arc beam show that surface was a little damaged.

• Corrosion Science and Technology
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• 제15권6호
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• pp.265-270
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• 2016

The ellipso-microscopic observation of a titanium surface undergoing anodization in $0.05mol\;dm^{-3}$ of $H_2SO_4$ was conducted. During irradiation by ultra-violet (UV) light with a wavelength of 325 nm, the titanium surface allowed for the flow of a photo-induced current and showed up as a bright, patch-like image on an ellipso-microscopic view. The brightness and patch-pattern in the image changed with flowing photo-induced current. The changes in the brightness and the image corresponded to the formation and/or degradation of titanium oxide due to the photo-electrochemical reaction of the oxide. An in situ monitoring using the ellipso-microscope revealed that the film change was dependent on the irradiation light power, by UV-light increases the anodic current and results in the initiation of pitting at lower potentials as compared with the non-irradiated condition.

• 한국결정성장학회지
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• 제17권5호
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• pp.196-203
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• 2007

We have studied a method for the preparation of hybrid $carbon/TiO_2$ complexes involving pitch coating, pitch binding and the penetration of titanium n-butoxide(TNB) solution with porous carbon. The photocatalysts were investigated with surface textural properties and SEM morphology, structural crystallinity and elemental identification between porous carbon and $TiO_2$, and dye decomposition performance. For the all $carbon/TiO_2$ complexes prepared by some kinds of different methods, the excellent photocatalytic effect for dye degradation should be attributed to the both effects between photo-decomposition of the supported $TiO_2$ and adsorptivity of the porous carbons.

• Journal of Electrochemical Science and Technology
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• 제3권1호
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• pp.44-49
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• 2012

Electrochemical and photochemical techniques have been proved to be effective for the removal of organic pollutants in textile wastewater. The present study deals with degradation of synthetic textile effluents containing reactive dyes and assisting chemicals, using electro oxidation and photo catalytic treatment. The influence of various operating parameters such as dye concentration, current density, supporting electrolyte concentration and lamp intensity on TOC removal has been determined. From the present investigation it has been observed that nearly 70% of TOC removal has been recorded for electrooxidation treatment with current density 5 mA/$dm^2$, supporting electrolyte concentration of 3 g/L and in photocatalytic treatment with 250 V as optimum lamp intensity nearly 67% of TOC removal was observed. The result indicates that electro oxidation treatment is more efficient than photocatalytic treatment for dye degradation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.286-291
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• 2001

As part of fundamental studies on the degradation of the organic compounds in industrial waste water, the photocatalytic degradation properties of the organic compound by means of the UV/TiO$_2$degradation process have been investigated. The test organic compound of acetic acid was chosen in this study. The testing of photo catalytic degradation were performed under various operation conditions such as TiO$_2$dosages, initial concentration of the organic, the aqueous pH's, etc. The effects of various parameters on the short time activity of the present acetic acid-UV/TiO$_2$system could be demonstrated from this investigation.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.968-971
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• 2005

Amorphous silicon photo diodes incorporated in a polyLED stack are applied in in pixel opticalfeedback to compensate for polyLED degradation. Large quantum efficiencies and perfect linearity are demonstrated. The photosensitivity is in agreement with optical modeling of the stack. A new scheme for ambient and cross talk light cancellation is given.

• Elastomers and Composites
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• 제44권4호
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• pp.408-415
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• 2009

졸-겔 방법을 사용하여 Fe-ACF/$TiO_2$ 복합체 광촉매를 제조하였다. 여러 가지 철 전구체를 사용하여 세가지 Fe-ACF/$TiO_2$ 복합체를 제조하고 BET, SEM, XRD 및 EDX를 사용하여 특성화 하였다. UV 조사에서 Rh.B 용액의 분해에 의거하여 Fe-ACF/$TiO_2$ 복합체의 광촉매 특성을 파악 하였다. 실험 결과로부터, Fe-ACF/$TiO_2$ 복합체는 ACF/$TiO_2$ 복합체 보다 Rh.B의 제거 효과가 더 우수함을 나타내었다. 또한 여러 가지 Fe 전구체 사용으로 인한 Fe 원소의 포토-펜톤 효과는 다르게 나타났다. $FeCl_3$을 사용하여 제조된 Fe-ACF/$TiO_2$ 복합체는 가장 우수한 포토-펜톤 효과를 나타내었고, pH 변화에 의존하여 Rh.B 용액 분해에 대하여 영향을 주었다.

• Elastomers and Composites
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• 제52권2호
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• pp.131-135
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• 2017

Zinc nitrate hexahydrate [$Zn(NO_3){\cdot}6H_2O$] and sodium hydroxide [NaOH] were used as source reagents in the preparation of ZnO nanoparticles in an aqueous solution containing deionized water and ethanol in a ratio of 2:5 (v/v). ZnO nanoparticles were heated in an electric furnace at $700^{\circ}C$ for 2 h under an atmosphere of inert argon gas. The morphological and structural properties of the nanoparticles were characterized by scanning electron microscopy (SEM) and powder X-ray diffractometry (XRD). UV-vis spectrophotometry was used to analyze the photocatalytic degradation of 3-nitrophenol with ZnO nanoparticles as photocatalyst under ultraviolet irradiation at 254 nm. Evaluation of the kinetic of the photo-catalytic degradation of 3-nitrophenol indicated that the degradation of 3-nitrophenol with ZnO nanoparticles obeyed the pseudo-first order reaction rate model.

• 대한토목학회논문집
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• 제28권4B호
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• pp.441-447
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• 2008

산업현장에서 발생되는 휘발성유기화합물은 생분해 가능한 화합물과 난분해성 물질이 혼합되어 있는 경우가 많으며, 저감기술을 단독으로 적용해서는 효과적인 제어가 불가능하다. 따라서 본 연구에서는 난분해성 물질이 혼합된 휘발성유기화합물을 처리하기 위하여, 자외선(UV) 광분해 장치와 미생물 고정화 복합고분자 담체가 적용된 바이오필터 기술을 결합한 통합시스템을 구성하고 반응 특성을 검토하였다. 대상 휘발성유기화합물로는 toluene과 TCE를 선정하였다. 자외선 광산화 단독실험 결과 TCE는 99% 이상의 제거효율을 나타내었으며 수용성 중간생성물 발생량도 크게 증가하였다. 그러나 toluene과 TCE를 혼합하여 유입시키면 자외선 광분해만으로는 유기화합물 제거율이 낮아졌다. 자외선 광산화와 바이오필터를 결합한 통합시스템 실험에서는 높은 toluene 제거효율을 얻을 수 있었으며, 전처리로 자외선을 조사한 후 toluene과 TCE의 처리효율도 함께 증가하는 것을 확인하였다. 이는 자외선에 의해 일부 산화된 toluene과 TCE가 미생물에 의해 보다 효과적으로 분해될 수 있음을 보여준다. 자외선 광산화 반응은 toluene이 상대적으로 적게 존재하는 상황에서 TCE 제거효율을 효과적으로 향상시킬 수 있었으며, 본 실험에서 확인한 TCE 최대 분해능은 $18.2g/m^3/hr$이었다. 그러나 toluene 유입농도가 높았던 조건에서는 toluene의 저해작용으로 인해 TCE 분해능 변화가 적었다. 다양한 운전조건에서 통합시스템의 반응효율과 운전 안정성을 향상시키기 위해서는 각 난분해성 물질 사이의 상호 저해작용에 대한 추가 연구가 필요하다.