• 제목/요약/키워드: Light reduction rate

검색결과 236건 처리시간 0.026초

금-펩타이드 하이브리드 나노입자의 제조와 메틸렌 블루의 촉매 환원 응용 (Preparation of Gold-Peptide Hybrid Nanoparticles and Its Applications in Catalytic Reduction of Methylene Blue)

  • 허윤미;민경익
    • 공업화학
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    • 제32권2호
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    • pp.163-167
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    • 2021
  • 본 연구에서는 타이로신이 풍부한 펩타이드, Tyr-Tyr-Leu-Tyr-Tyr (YYLYY)를 이용하여 금 나노입자를 담지한 균일한 금-펩타이드 계층적 초분자 구조체의 합성에 대해 연구하였다. 펩타이드의 광가교 반응을 통해 다이타이로신 결합으로 자기조립된 펩타이드 나노입자를 합성하였고, 타이로신의 생체 광물화 특성을 이용하여 금-펩타이드 하이브리드 나노입자를 친환경적 방법으로 합성하였다. 합성된 금-펩타이드 하이브리드 나노입자는 투과 전자 현미경(TEM), 주사투과 전자 현미경(SEM), 동적 광산란(DLS), 자외선-가시광선 분광광도계(UV-Vis spectroscopy), 에너지 분산 X선 분광법(STEM-EDS), X선 회절 분석법(XRD)을 통해 분석하였다. 또한 합성된 금-펩타이드 하이브리드 나노입자는 메틸렌블루의 환원 반응에서 13.4 × 10-3 s-1의 반응속도 상수를 가지는 촉매 특성을 확인하였다.

감국 추출액으로 염색한 키토산/나노실버 복합편성물의 염착특성 (Absorption Properties of Chitosan and Nano Silver Composite knit Fabrics Dyed with Chrysanthemum indicum Linn Extract)

  • 주영주
    • 한국의류산업학회지
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    • 제12권6호
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    • pp.837-842
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    • 2010
  • This study examines the dyeability, light fastness, washing fastness, and antibacterial activity of chitosan and nano silver composite knit fabrics dyed with extracted solution from Chrysanthemum Indicum Linn. The results show that ${\Delta}E$ values of chitosan and nano silver composite knit fabrics were higher than cotton 100% knit fabrics in dyed condition with extracted solution from Chrysanthemum Indicum Linn, and mordant treatments influenced the chrominance change. Chrysanthemum indicum Linn confirmed that this could be a polygenetic colors. ${\Delta}E$ values of post-mordant treatments knit fabrics were higher than pre-mordant treatments knit fabrics in dyed condition with extracted solution from Chrysanthemum Indicum Linn., and mordant treatments method influenced the chrominance change. The dyeability of chitosan and nano silver composite knit fabrics was increased by mordant treatment. The fastness of the chitosan and nano silver composite knit fabrics was better than cotton 100% knit fabrics. In the result of antibacterial activity, the bacterial reduction rate of chitosan and nano silver composite knit fabrics was 99.9% to Staphylococcus aureus and Klebsiella pneumoniae.

마이크로터빈이 포함된 빌딩마이크로그리드시스템의 병원건물의 에너지성능평가 (Energy Performance Evaluation of Building Micro-grid System Including Micro-turbine in Hospital Buildings)

  • 김병수;홍원표
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2009년도 추계학술대회 논문집
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    • pp.279-283
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    • 2009
  • Distributed generation(DG) of combined cooling, heat. and power(CCHP)has been gaining momentum in recent year as efficient, secure alternative for meeting increasing energy demands. This paper presents the energy performance of microturbine CCHP system equipped with an absorption chiller by modelling it in hospital building. The orders of study were as following. 1)The list and schedule of energy consumption equipment in hospital were examined such as heating and cooling machine, light etc. 2) Annual report of energy usage and monitoring data were examined as heating, cooling, DHW, lighting, etc. 3) The weather data in 2007 was used for simulation and was arranged by meteorological office data in Daejeon. 4) Reference simulation model was built by comparison of real energy consumption and simulation result by TRNSYS and ESP-r. The energy consumption pattern of building were analyzed by simulation model and energy reduction rate were calculated over the cogeneration. As a result of this study, power generation efficiency of turbine was about 30% after installing micro gas turbine and lighting energy as well as total electricity consumption can be reduced by 40%. If electricity energy and waste heat in turbine are used, 56% of heating energy and 67% of cooling energy can be reduced respectively, and total system efficiency can be increased up to 70%.

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인지질(DOPC)과 지방산(8A5H)의 혼합 LB막의 광이성질화 현상과 전기화학적 특성 (Electrochemical Properties and Photoisomerization of DOPC-8A5H Mixture Langmuir-Blogett Films)

  • 박근호;최성현;김남석;김덕술
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.874-877
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    • 2004
  • We carried out this subject to observe electrochemical properties of 1,2-dioleoyl-sn- glycero-3-phosphocholine(DOPC) mixed with fatty acid containing azobenzene group by using cyclic voltammetry with a three-electrode system, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode in $NaClO_4$ solution. We investigated the photoisomerization and electrochemical property of the organic ultra thin film of fatty acid containing azobenzene was prepared on the hydrophilic ITO(idium tin oxide) glass plate by LB method. As a result, the absorption spectra of BASH and DOPC of mixture LB films was induced to photoisomerization by alternating irradiation of ultraviolet and visible light. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rate were 50, 100, 150 and 200 mV/s. As a results, LB films of BASH-DMPC appeared reversible process caused by the reduction-oxidation current from the cyclic voltammogram.

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Mannose 처리된 배추 잎의 무기인산 감소에 따른 비광화학성 소산의 증가 (Sequestration of Orthophosphate by D(+)-Mannose Feeding Increases Nonphotochemical Quenchings in Chinese Cabbage Leaves)

  • 박연일
    • Journal of Plant Biology
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    • 제34권4호
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    • pp.303-309
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    • 1991
  • Limitation of photosynthesis in detached Chinese cabbage (Brassica campestris L.) leaves was induced by feeding of mannose (25 mM) for 12 h in the light, and changes in the basic thylakoid functions under this condition were investigated. The acid soluble phosphate contend and CO2 uptake rate was decreased by 66% and 67%, respectively. However, the starch content was increased by 24% compared to those of controls. From the fast induction curves of chlorophyll fluorescence, dark level fluorescence (Fo) slightly increased while intermediate plateau fluorescence level (FI) to peak level fluorescence (Fp) transient was significantly decreased with a slight decrease in the Fo-to-FI transient. This data means that reduction of secondary electron acceptor of PSII (QB) might be more severely inhibited than that of primary electron acceptor of PSII (QA) by decrease in phosphate level. The strong decline of (Fv)m//Fm ratio suggests that efficiency of excitation energy capture by PSII was decreased markedly. The quenching of Fo (qO), an indicator of state transition, was also occurred over the slow induction kinetics of chlorophyll fluorescence. From quenching analysis, fluorescence was dominantly quenched by nonphotochemical quenchings (qE+qT). These results showed that the capture and transfer efficiency of excitation energy to PSII reaction center in thylakoid was decreased with the decline of leaf phosphate level, and that the state transition was occurred during the induction of photosynthesis under these conditions.

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N-3rP 지방산이 나이가 다른 흰주의 신장 기능에 미치는 영향 (Effects of N-3 Fatty Acids on Renal Function in Rats of Different Ages)

  • 김화영
    • Journal of Nutrition and Health
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    • 제33권2호
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    • pp.134-140
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    • 2000
  • This study was performed to investigate the effects of n-3 fatty acids on renal function in male Sprague-Dawley rats of different ages 5-, 15- and 19-months old. The rats were fed a 20%(w/w) lipid diet containing 10% fish oil, compared with control animals fed a 20% lipid diet without fish oil for 4 weeks. The results were as follows: kidney weights were significantly higher in fish oil-fed rats compared to control rats. Plasma levels of total lipid, total cholesterol, and triglyceride markedly increased, with aging and LDL-cholesterol showing a significantly lower level in fish oil-fed rats than control rats. The urinary protein and glomerular filtration rate (GFR) increased with aging. GFR was higher in fish oil-fed rats. However, urinary protein was the same in the two groups. Renal medulla thromboxane B$_2$(TXB$_2$)tended to be lower in fish oil-fed 19-month-old rats. Urinary TXB$_2$and PGE$_2$were found to be higher proteinuria. Light microscopic examination showed interstitial inflammation, tubular atrophy, interstitial fibrosis and glomerular mesangium increase. Although glomerular sclerosis increased with aging, fish oil in the diet had no effect on histological changes. In conclusion, plasma lipid, urinary protein excretion and renal histological change showed a significant increase with aging. The reduction of TXB$_2$in the medulla and increase of GFR caused by fish oil indicated n-3 fatty acid could affect renal function in line with the hypolipidemic effect.

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주택용 3kW 태양광발전시스템의 구성요소법 특성 분석 (Characteristics analysis of Residential 3kW PV System)

  • 변문걸;박정국;임홍우;이강연;조금배;백형래
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.1181-1182
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    • 2006
  • The solar power system comprises a solar battery that directly converts light energy to electrical energy with a photovoltaic effect and a power converter system, that is, inverter that converts direct current power, which is generated from solar battery to common alternating current. In this paper, database was constituted through remote monitoring supervision measurement for the long-time positive operation of 3kW solar power system installed within the solar energy positive research complex of Chosun University. As a result of analyzing the reduction of the efficiency of solar battery and inverter that are compositional components of PV system through an analysis on the acquired data, the PV output was proven over 65% of the total output when insolation intensity exceeded 600W/m2 in 2005, and the array conversion efficiency dropped much more than rating; meanwhile, insolation intensity dropped below 600W/m2. Therefore, it has been demonstrated that approximately 35% of the entire amount of PV output operated under the condition that the inverter efficiency rate dropped rapidly by 60 to 70%.

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Photocatalytic activity enhancement of TiO2 with adding Zn particles

  • Seo, Hyeon Jin;Boo, Jang Heon;Jang, Hyun Woo;Kim, Mi Jeong;Boo, Jin-Hyo
    • Applied Science and Convergence Technology
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    • 제25권6호
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    • pp.162-165
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    • 2016
  • APhotocatalysis process uses ambient oxygen from air and irradiation, fundamentally UV light, to generate oxidation and reduction which can degrade almost all harmful organic and inorganic compounds to nontoxic substances. This study was focused on enhancement of photocatalytic activity which improves the photocatlytic efficiency with $TiO_2$ particle by mixing of certain amounts of Zn particles. We analyzed degradation of organic pollutant materials such as toluene and phenol with the mixed photocatalysis by using UV-visible spectrophotometer and obtained a result that photocatalytic activity is increased with increasing amount of Zn particle. Especially, in the case of $TiO_2$ (1 mmol) and Zn (0.1 mmol) mixture photocatalyst, we obtained at least 2 times higher photocatalytic activity compared with the commercially available $TiO_2$ photocatalyst (Degussa P-25), indicating that our mixed photocatalyts (Zn-doped $TiO_2$) is very effective of removing both organic dye and pollutants and the conversion rate of toluene is much faster than that of phenol.

마그네슘용탕의 니켈 함량에 미치는 알루미늄, 망간 및 지르코늄의 영향 (Effect of Aluminum, Manganese, and Zirconium on the Content of Nickel in Molten Magnesium)

  • 정대영;문영훈;문병기;박원욱;손근용
    • 한국주조공학회지
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    • 제35권1호
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    • pp.8-14
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    • 2015
  • Variations of nickel contents and microstructures in molten magnesium alloys on the addition of aluminum, zirconium, and manganese have been investigated. Specimens were prepared by melting under $SF_6$ and $CO_2$ atmosphere and casting into a disc of 29 mm diameter with 7~10 mm thickness from the melt acquired at the top of crucible. Before casting, the molten metal was stirred for 3 minutes after each addition of alloying elements and maintained for 30 minutes for settling down. Results showed that zirconium did not significantly affect the content of nickel while aluminum remarkably reduced it by forming $Al_3Ni_2$ phase. When manganese are added to Mg-1wt%Ni alloy along with aluminum, both elements remarkably reduced the content of nickel. The addition of 1.5 wt% manganese to Mg-1wt%Ni alloy containing aluminum further reduced the content of nickel by more than 30%, during which an additional intermetallic phase $Al_{10}Mn_3Ni$ was precipitated in the molten magnesium.

Photocatalytic degradation of textile dye CI Basic Yellow 28 wastewater by Degussa P25 based TiO2

  • Konecoglu, Gulhan;Safak, Toygun;Kalpakli, Yasemen;Akgun, Mesut
    • Advances in environmental research
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    • 제4권1호
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    • pp.25-38
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    • 2015
  • Wastewaters of textile industry cause high volume colour and harmful substance pollutions. Photocatalytic degradation is a method which gives opportunity of reduction of organic pollutants such as dye containing wastewaters. In this study, photocatalytic degradation of C.I. Basic Yellow 28 (BY28) as a model dye contaminant was carried out using Degussa P25 in a photocatalytic reactor. The experiments were followed out at three different azo dye concentrations in a reactor equipped UV-A lamp (365 nm) as a light source. Azo dye removal efficiencies were examined with total organic carbon and UV-vis measurements. As a result of experiments, maximum degradation efficiency was obtained as 100% at BY28 concentration of $50mgL^{-1}$ for the reaction time of 2.5 h. The photodegradation of BY28 was described by a pseudo-first-order kinetic model modified with the langmuir-Hinshelwood mechanism. The adsorption equilibrium constant and the rate constant of the surface reaction were calculated as $K_{dye}=6.689{\cdot}10^{-2}L\;mg^{-1}$ and $k_c=0.599mg\;L^{-1}min^{-1}$, respectively.