• Journal of Biosystems Engineering
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• 제37권3호
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• pp.209-213
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• 2012

Purpose: This study was performed to develop a simple, disposable thin-film optical nitrate sensor. Methods: The sensor was fabricated by applying a nitrate-selective polymer membrane on the surface of a thin polyester film. The membrane was composed of polyvinylchloride (PVC), plasticizer, fluorescent dye, and nitrate-selective ionophore. Fluorescence intensity of the sensor increased on contact with a nitrate solution. The fluorescence response of the optical nitrate sensor was measured with a commercial fluorospectrometer. Results: The optical sensor exhibited linear response over four concentration decades. Conclusions: Nitrate ion concentrations in plant nutrient solutions can be determined by direct optical measurements without any conditioning before measurements.

• 대한화학회지
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• 제64권2호
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• pp.74-78
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• 2020

산성 영역에서 작동하는 고감도 형광 pH 센서막을 제조하기 위하여 실란화된 유리 표면 상에 push-pull 공액 염료(DCMP)를 공유결합에 의해 고정화하였다. DCMP 유도체(DCMA), 2-hydroxyethyl methacrylate (HEMA)및 triethylene glycol dimethacrylate의 혼합물을 광개시 공중합하여 pH 감응성 형광센서막을 제조하였다. 분광학적 측정 결과, pH 2.0-5.0 사이에서 pH가 증가함에 따라 센서막의 흡광도가 증가하였으며, 같은 pH 범위에서 pH 증가에 따라 센서막의 형광 세기도 약 50배 정도 증가하였다. 산성 조건에서 pH 변화에 대한 센서막의 감응은 가역적이고 재현성이 우수하였다. 또한 센서막은 20-50초 사이의 비교적 짧은 감응 시간과 여러 금속이온 존재에서 수소 이온에 대해 높은 선택성을 나타내었다.

• Current Optics and Photonics
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• 제5권1호
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• pp.1-7
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• 2021

For higher sensitivity in ultraviolet (UV) and even vacuum ultraviolet (VUV) detection of silicon-based sensors, a sandwich-structured film sensor based on Ag Localized Surface Plasmon Resonance (LSPR) was designed and fabricated. This film sensor was composed of a Ag nanoparticles (NPs) layer, SiO2 buffer and fluorescence layer by physical vapour deposition and thermal annealing. By tuning the annealing temperature and adding the SiO2 layer, the resonance absorption wavelength of Ag NPs matched with the emission wavelength of the fluorescence layer. Due to the strong plasmon resonance coupling and electromagnetic field formed on the surface of Ag NPs, the radiative recombination rate of the luminescent materials and the number of fluorescent molecules in the excited state increased. Therefore, the fluorescent emission intensity of the sandwich-structured film sensor was 1.10-1.58 times at 120-200 nm and 2.17-2.93 times at 240-360 nm that of the single-layer film sensor. A feasible method is provided for improving the detection performance of UV and VUV detectors.

• 마이크로전자및패키징학회지
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• 제25권3호
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• pp.37-41
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• 2018

본 논문에서는 UV 임프린트 기반의 평면 광 회로층을 이용한 산소농도 검출용 집적형 형광 프로브 모듈을 제안하였다. 제안된 형광 프로부 모듈은 광원과 형광 신호를 고효율로 전송할 수 있게 동일 광 경로를 가지는 비대칭 $1{\times}2$ 빔 분배기 형태로 설계되었으며, 이를 UV 임프린트 공정을 통해 제작하였다. 제작된 광 회로층의 끝단에 최적의 형광 염료 농도로 센서막을 코팅하여 산소 농도 검출용 광학 프로브 모듈을 구현하였다. 제작된 형광 프로부 모듈을 이용한 산소 농도 측정용 센서 시스템은 0%에서 20%의 가스 농도 범위에서 약 0.3%의 분해능까지 산소 농도를 검출 할 수 있었다. 이러한, 평면 광회로 기반의 형광 프로브 모듈은 저가의 집적형 산소 센서 검출 시스템을 가능하게 하여, 화학분야, 바이오 분야, 그리고 대기 및 수질 환경을 모니터링 하는 분야에 적용될 수 있을 것으로 기대된다.

• 설비공학논문집
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• 제25권12호
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• pp.668-673
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• 2013

In this study, specimens with nano-sized porous thin films were manufactured by injecting fluorescence solution into the pores. We intended to find out the difference of the fluorescence intensity in each region of the specimen through an experimental apparatus that makes a temperature field. Before conducting experiments, the optimized manufacturing conditions were determined by analysis of all parameters that influence the emission intensity, and the experiments were carried out with the specimens produced in the optimized conditions. Then, the calibration curves of the fluorescence intensity versus temperature were performed by taking the intensity distributions from the specimen in various temperature fields. The surfaces of specimens were coated with Rhodamine-B (Rh-B) fluorescent dye and measured based on the fluorescence intensity. Silica (SiO2) nanoporous structure with 1-um thickness was constructed on a cover glass, and fluorescence dye was absorbed into these porous thin films.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2001년도 Proceedings of 6th International Joint Symposium on Microeletronics and Packaging
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• pp.57-65
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• 2001

Economical consumption of energy, longer life of lamps, higher lighting comfort and new aesthetic of illumination is subject of numerous research and development works. The halogen lamps are an example of positive solution some of above mentioned problems. The electronic transformers are more frequent used for their supply. In comparison with conventional transformers they have less weight, less volume and 60% less power tosses. Their advantages are particular visible, when the hybrid technique is applied. The paper presents the results of engineering research and development works carried out ill Private Institute of Electronic Engineering, in R. & D. Center for Hybrid Microelectronics and Resistors and in Technical School of Communications in Krakow, in the field of the design and exploitation tests of hybrid converters 220V AC /12V DC (electronic transformers) and electronic ballasts destined for the supply of halogen lamps 20W to 150W and fluorescent lamps respectively. To perform the converters, thick film technology and surface mount technology were used. For the protection of converter electronic circuit the thick film temperature sensor and transistors were applied. Moreover the paper presents the base application circuits of elaborated converters, their technical parameters and exploitation results. The development perspectives of hybrid domain of hybrid circuits are also discussed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2692-2695
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• 2008

Polydiacetylene (PDA) is chemosensor materials that exhibit non-fluorescent-to-fluorescent transition as well as blue-to-red visible color change upon chemical or thermal stress. They have been studied in forms of film or microarray chip, so far. In this paper, we provide a novel technique to fabricate continuous micro-fiber PDA sensor using in-situ laser-polymerization technique and 3-D hydrodynamic focusing on a microfluidic chip. The flow of a monomer solution with diacetylene (DA) monomer is focused by a sheath flow on a 3-D microfluidic chip. The focused flow is exposed to 365 nm UV laser beam for in-situ polymerization which generates a continuous fiber containing DA monomers. Then, the fiber is exposed to 254 nm UV light to polymerize DA monomers to PDA. Preliminary results indicate that the fiber size can be controlled by the flow rates of the monomer solution and sheath flows and that a PDA sensor fiber successively responds to chemical and thermal stress.

• 마이크로전자및패키징학회지
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• 제8권2호
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• pp.43-48
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• 2001

Economical consumption of energy, longer life of lamps, higher lighting comfort and new aesthetic of illumination is subject of numerous research and development works. The halogen lamps are an example of positive solution some of above mentioned problems. The electronic transformers are more frequent used for their supply. In comparison with conventional transformers they have less weight, less volume and 60% less power losses. Their advantages are particular visible, when the hybrid technique is applied. The paper presents the results of engineering research and development works carried out in Private Institute of Electronic Engineering, in R. & D. Center for Hybrid Microelectronics and Resistors and in Technical School of Communications in Krakow, in the field of the design and exploitation tests of hybrid converters 220V AC /12V DC (electronic transformers) and electronic ballasts destined for the supply of halogen lamps 20W to 150W and fluorescent lamps respectively. To perform the converters, thick film technology and surface mount technology were used. For the protection of converter electronic circuit the thick film temperature sensor and transistors were applied. Moreover the paper presents the base application circuits of elaborated converters, their technical parameters and exploitation results. The development perspectives of such domain of hybrid circuits are also discussed.

• 센서학회지
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• 제4권4호
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• pp.81-87
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• 1995

A novel biomaterial capable of incorporating biotinylated biomolecule has been synthesized. Our strategy is to biotinylate one-dimensional electroactive polymers and use a bridging streptavidin protein on Langmuir-Blodgett (LB) organized films. These copolymers are derivatized with long alkyl chains and biotin moieties to bind, respectively, to the hydrophobic surface and the biotinylated species, through the biotin and streptavidin complexation. We utilize the polymer assembly approach to attach a signal transducing biomolecule biotinylated phycoerythrin (B-PE) into this novel biomaterial by binding the unoccupied biotin binding sites on the bound streptavidin (4 sites total). The pressure-area isotherm of the protein injected monolayer showed area expansion. A characteristic fluorescent emission peak at 576nm was detected from the monolayer transferred onto a solid substrate. These observations demonstrated the promise of the organized thin polymer assemblies for their application to the sensor system.

• 폴리머
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• 제32권2호
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• pp.189-192
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• 2008

Styrylpyrylium salt 화합물(DHSP)을 합성하고 광이량화시켜 cyclobutane형 이량체(DHSP dimer)를 합성하였다. 여기에 메타크릴레이트기를 도입하여 DMSP dimer를 합성하였다. DMSP dimer 광가교물의 FT-IR 분석 결과, 크랙 생성에 의해 cyclobutane환이 개열되어 styryl C=C 구조로 되돌아가는 것으로 판단되었다. 385 nm의 빛에 의하여 DHSP는 626 nm의 형광을 방출하는 반면 DHSP dimer는 매우 약한 형광만을 나타내었다. DMSP dimer의 광가교 필름에 microcrack을 생성시키고 $330{\sim}385\;nm$의 빛을 조사한 결과, 크랙 부분에서의 형광 방출이 확인되었다.