• 에너지공학
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• 제22권3호
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• pp.250-261
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• 2013

현대 사회에서 우리는 주로 화석 연료 인프라 위에 구축된 화석 연료 경제 시대에 살고 있다. 그 결과 발생하는 에너지 도전문제(예: 화석 연료의 자원 고갈 문제, 환경 오염 문제, 에너지 안보 문제)로 지속가능 발전은 한계에 부딪히고 있는 실정이다. 이들 도전문제를 극복하기 위해 기존 석유-기반 리파이너리, 즉 석유 정제(ORF) 역할을 대체할 바이오에너지(예: 바이오연료, 전기, 열) 및 바이오케미컬 (예: C5 계열, C6 계열) 동시-생산 시스템으로 바이오매스를 사용한 바이오리파이너리(BRF) 개념이 새롭게 출현하였다. 이는 석유 경제에서 바이오경제로 패러다임 천이(shift)가 진행되고 있음을 가리키는 지표(indicator)가 된다. 이러한 바이오매스-기반 경제는 현재 구축되어 있는 ORF 인프라를 거의 변경 없이 그대로 활용할 수 있는 높은 호환성, 적은 폐기물 발생량, 이산화탄소 중성적 친환경성, 지역 농업/임업 경제 활성화 등과 같은 매력적인 강점들을 갖고 있다. 무엇보다도 석유 자원 빈곤국이 고 석유 수입국이며 ORF 인프라를 이미 구축한 우리나라에서는 에너지 안보 및 지속가능 발전 측면에서 고가치 BRF 시스템의 연구 개발 및 기술 사업화에 국가적 차원에서 아낌없이 투자와 지원을 제공해야 할 필요성이 높아지고 있다. 이 연구에서는 바이오에너지/바이오케미컬 동시-생산용 시스템으로 활용될 BRF 기술의 국내외 동향을 소개하고자 한다.

• 공업화학
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• 제30권3호
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• pp.280-289
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• 2019

5-Hydroxymethylfurfural (HMF) 및 그 유도체들인 2,5-furandicarboxylic acid (FDCA)와 2,5-diformylfuran (DFF)는 넓은 응용 범위와 중요한 화학 물질 생산을 위한 좋은 대체 자원으로 인해 "잠자는 거인"으로 인식되고 있다. 본 미니-리뷰 논문은 과거부터 최근까지 이러한 바이오매스 유래 케미컬 플랫폼들에 대한 합성, 전환과 적용에 관해 간략히 소개한다. 많은 과학적 노력들이 자연 환경과 새로운 미래 세대를 보호하기 위해서 재생 가능한 재료들의 최대한 활용을 위한 자연친화적-적용가능한 방법들을 찾기 위한 노력이 지속적으로 행해지고 있다. 최선의 해결책 중 하나는 자연바이오매스로부터 플랫폼 케미컬을 개발하고 활용하는 것이다.

• 청정기술
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• 제17권3호
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• pp.280-282
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• 2011

광에너지를 이용하여 바이오원료 및 바이오케미컬을 생산하려는 새로운 시도가 많은 관심을 받고 있다. 특히, 광합성기작을 이용한 다양한 바이오유래 물질을 생산하려는 연구가 진행되고 있다. 본 연구에서는 광합성기작을 갖고 있는 해양 미생물인 Salinibacter ruber의 세포막에서 retinal과 salinixanthin의 작용으로 광전자를 흡수하는 역할을 하는 잔토로돕신을 수성 이상계 계면 농축법을 이용하여 효율적으로 분리하였다. 분리된 잔토로돕신을 생물학적 세포막인 레시틴으로 리포좀을 생성하여 잔토로돕신의 광전자흡수 활성을 그대로 갖는 인위적인 잔토로돕신-레시틴 리포좀을 제작하였다.

• 센서학회지
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• 제30권3호
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• pp.131-138
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• 2021

The optimization of the specifications of vertical silicon on insulator (SOI) slot optical waveguides suitable for integrated-optical biochemical sensors was performed through computational analysis of the confinement factor of the guided mode distributed in the slot in addition to analytical examination of the TE mode. The optimized specifications were confirmed based on sensitivity in terms of the change in the refractive index of the biochemical analyte. When the slot width, rail width, and height were set to 120 nm, 200 nm, and 320 nm, respectively, the confinement factor was evaluated to be about 56% and the sensitivity was at least 0.9 [RIU/nm].

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1767-1772
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• 2008

A microcantilever is a well-known MEMS structure for sensing bio-chemical molecules. When bio-chemical molecules are adsorbed on the microcantilever's surface, resonance frequency shift is generated. There are two issues in this phenomena. The first one is which one between mass change and surface stress change effects is more dominant on the resonance frequency shift. The second one is what will be the performance change when the boundary condition is changed from cantilevers to double clamped beams. We have studied the effect of surface stress change and compared it with that of mass change by using FEM analysis. Furthermore, for microstructures having different boundary conditions, we have studied Q-factor, which determines the detection limit of micro/nano mechanical sensors.

• 센서학회지
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• 제31권2호
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• pp.107-114
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• 2022

The effects of ring radius and coupling spacing on the free spectral range (FSR), full width at half maximum (FWHM), quality factor, and sensitivity of single-channel and add-drop channel slot ring resonators were systematically investigated using FIMMPROP and PICWAVE numerical software. The single-channel ring resonator exhibited better characteristics, namely, a wider FSR and narrower FWHM compared with the add-drop structure; thus, it was evaluated to be more suitable for biochemical sensors. The FSR, FWHM, quality factor, and sensitivity for a single channel ring resonator with a radius of 59.4 ㎛ and coupling gap of 0.5 ㎛ were 2.4 nm, 0.087 nm, 17677, and 550 [nm/RIU], respectively.

• 센서학회지
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• 제31권5호
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• pp.353-359
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• 2022

This study investigated via computational analysis the application utility of series-cascaded ring resonators based on silicon-on-insulator (SOI) slot optical waveguides in integrated optical biochemical sensors. The radii of the two rings in the series-cascaded ring resonators were 59.4 ㎛ and 77.6 ㎛ respectively, and the coupling distance was 0.5 ㎛. The series-cascaded ring resonators were computationally analyzed using FIMMProp and PICWave numerical software. The free spectral range (FSR), full width at half maximum (FWHM), sensitivity, and quality-factor (Q-factor) of the series-cascaded ring resonators were 12.2 nm, 0.134 nm, 4100 nm/RIU, and 11580, respectively, and the measurement range was calculated to be slightly smaller than 3×10^-3 RIU. Although the measurement range was smaller than that of the single ring resonator, upon considering other characteristic parameters, the series-cascaded ring resonators are found to be more effective as integrated sensors than single ring resonators.

• 센서학회지
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• 제30권3호
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• pp.139-147
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• 2021

Numerical analysis was performed using FIMMWAVE to optimize the specifications of Si₃N₄/SiO₂ slot and ridge-slot optical waveguides based on confinement factor and effective mode area. The optimized specifications were confirmed based on sensitivity in terms of the refractive index of the analyte. The specifications of the slot optical waveguide, i.e., the width of the slot and the width and height of the rails, were optimized to 0.2 ㎛, 0.46 ㎛, and 0.5 ㎛ respectively. When the wavelength was 1.55 ㎛ and the refractive index of the slot was 1.3, the confinement factor and effective mode area of 0.2024 and 2.04 ㎛², respectively, were obtained based on the optimized specifications. The thickness of the ridge and the refractive index of the slot were set to 0.04 ㎛ and 1.1, respectively, to optimize the ridge-slot optical waveguide, and the confinement factor and effective mode area were calculated as 0.1393 and 2.90 ㎛², respectively. When the confinement coefficient and detection degree of the two structures were compared in the range of 1 to 1.3 of the analyte index, it was observed that the confinement coefficient and sensitivity were higher in the ridge-slot optical waveguide in the region with a refractive index less than 1.133, but the reverse situation occurred in the other region. Therefore, in the implementation of the integrated optical biochemical sensor, it is possible to propose a selection criterion for the two parameters depending on the value of the refractive index of the analyte.

• 센서학회지
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• 제32권4호
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• pp.223-231
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• 2023

An integrated-optical biochemical sensor structure that can perform homogeneous and surface sensing using a 2×2 balanced-bridge Mach-Zehnder interference structure based on the optimized SOI slot optical waveguide was described, and its performance and characteristics were evaluated. Equations for the two output optical powers were derived and examined using the transfer matrices of a 3-dB coupler and phase shifter (channel waveguide). The length of the 3-dB coupler was determined such that the two output optical powers were same using these formulas. In homogeneous sensing, the effect of the refractive index of an analyte in the range of 1.33-1.36 on the two output optical power distributions was numerically derived, and the sensitivity was calculated based on each output and the difference between the two outputs, the former and the latter being 7.5796-19.0305 [au/RIU] and 15.2601-38.1351 [au/RIU], respectively. In the case of surface sensing, the sensitivity range of the refractive index of 1.337 based on each of the two outputs was calculated as -2.2490--3.5854 [au/RIU] and 1.2194-3.8012 [au/RIU], and the sensitivity range of 4.8048-7.0694 [au/RIU] was confirmed based on the difference between the two outputs.