• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3735-3737
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• 2011

We report a simple method for fabricating ZnO gas sensors via a sonochemical route and their $H_2$ gas sensing properties. Vertically aligned ZnO nanorod arrays as a sensing material were synthesized on a Pt-electrode patterned alumina substrate under ambient conditions. The advantage of the proposed method is a high speed of processing. The gas sensor based on ZnO nanorod arrays with large specific surface area showed a high response to $H_2$ and a detection limit of 70 ppm at $250^{\circ}C$. Also, their response and recovery time were relatively short and a complete regeneration was observed. A mechanism for sensing $H_2$ gas on the surface of ZnO nanorods is proposed.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2933-2937
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• 2011

A new highly selective receptor (3) based on an acridine-imidazolium functionalized cholestane for anion sensing was designed and synthesized. A binding study of 3 with various anions was assessed by UV-vis and fluorescence spectroscopies in dry CH3CN. Receptor 3 showed the highest selectivity toward hydrogen pyrophosphate (Ka = $1.5{\times}10^4M^{-1}$).

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.3123-3126
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• 2011

• 청정기술
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• 제11권2호
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• pp.75-81
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• 2005

나노기술의 발전은 기존 환경기술의 패러다임 자체를 변화시키고 있다. 나노수준에서의 환경문제의 이해를 바탕으로 하는 환경기술 정책들이 추진되고 있으며, 청정공정기술의 구현을 위한 통합환경관리로의 개념 전환이 이루어지고 있다. 본 논고에서는 이러한 개념을 바탕으로 청정기술을 위한 나노기술기반 환경 센싱 및 모니터링 기술의 필요성에 대하여 소개하고자 한다. 현재 국내의 환경 시장은 상당부분 외국기술에 의존하고 있지만, 정부의 나노기술에 대한 집중 투자로 인해 나노기술을 활용한 환경 센싱 및 모니터링 분야의 발전이 있을 것으로 기대한다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.224.1-224.1
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• 2003

Recent studies have revealed that bacterial biofilm production by the gram-negative bacteria is regulated by the quorum sensing signaling molecules, AHLs (N-acyl homoserine lactones). This suggests that inhibiting the AHLs could enhance the effects of antibacterial agents. Halogenated furanones purified from the red algae Delisea pulchra have been known to decrease quorum sensing responses by competitive inhibition of the AHLs. (omitted)

• 센서학회지
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• 제17권2호
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• pp.143-146
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• 2008

Polymer-coated film SAW sensors have been fabricated and their sensing properties for toxic chemicals have been extensively investigated. Four types of the toxic chemical compounds of hydrogen cyanide(AC), carbonyl dichloride(CG), pinacolyl methylfluorophosphonate(GD), 2,2'-dichlorodiethylthio ether(HD) were used as target gases. SAW sensors using five different kinds of polymers were used to detect toxic chemicals and their gas sensing characteristics were investigated. The polymers used as the sensing materials were polyisobutylene(PIB), polyepichlorohydrin(PECH), polydimethylsiloxane(PDMS), polybutadiene(PBD) and polyisoprene(PIP). The recommendable mixing ratio of PIB, PECH, PDMS, PBD and PIP to solvents were 1:30, 1:40, 1:10, 1:30 and 1:30, respectively. The sensing characteristics of the SAW sensors were measured by using E-5061A network analyzer.

• 센서학회지
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• 제20권6호
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• pp.428-433
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• 2011

We report on the building of a micro sensor array based on typical semiconductor fabrication processes aimed at monitoring selectively a specific gas in ambient of other gases. Chemical sensors can be applied for an electronic nose and/or robots using this technique. Microsensor array was fabricated on the same chip using 0.6${\mu}m$ CMOS technology, and unique gas sensing patterns were obtained by principal component analysis from the array. $SnO_2$/Pt sensor for CO gas showed a high selectivity to buthane gas and humidity. $SnO_2$ sensor for hydrogen gas, however, showed a low selectivity to CO and buthane gas. We can obtain more distinguishable patterns that provide the small sensing deviation(the high seletivity) toward a given analyte in the response space than in the chemical space through the specific parameterization of raw data for chemical image formation.

• 한국결정성장학회지
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• 제22권2호
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• pp.84-91
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• 2012

Single and few-layer graphene nanosheets (GNs) have successfully synthesized by a modified Hummer's method followed by chemical reduction of exfoliated graphene oxide (GO) in the presence of hydrazine monohydrate. GO and GNs were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), X-ray diffractions (XRD), Raman spectroscopy, Transmission electron microscopy (TEM), Atomic force microscopy (AFM), Optical microscopy (OM) and by electrical conductivity measurements. The result showed that electrical conductivity of GNs was significantly improved, from $4.2{\times}10^{-4}$ S/m for GO to 12 S/m for GNs, possibly due to the removal of oxygen-containing functional group during chemical reduction. In addition, the $NO_2$ gas sensing characteristics of GNs are also discussed.

• 한국전기전자재료학회논문지
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• 제25권2호
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• pp.125-128
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• 2012

We fabricated the electrolyte-insulator-semiconductor (EIS) devices with various high-k sensing membranes to realize a high quality pH sensor. The sensing properties of each high-k dielectric material were compared with those of conventional $SiO_2$ (O) and $SiO_2/Si_3N_4$ (ON) membranes. As a result, the high-k sensing membranes demonstrated better sensitivity and stability than the O and ON membranes. Especially, the $SiO_2/HfO_2$ (OH) stacked layer showed a high sensitivity and the $SiO_2/Al_2O_3$ (OA) stacked layer exhibited an excellent chemical stability. In conclusion, the high-k sensing membranes are expected to have excellent operating characteristics in terms of sensitivity and chemical stability for the biosensor application.

• 센서학회지
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• 제32권2호
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• pp.75-81
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• 2023

The significance of gas sensors has been emphasized in various industries and applications, owing to the growing significance of environmental, social, and governance (ESG) management in corporate operations. In particular, the monitoring of hazardous gas leakages and detection of fugitive emissions have recently garnered significant attention across several industrial sectors. As industrial workplaces evolve to ensure the safety of their working environments and reduce greenhouse gas emissions, the demand for high-performance gas sensors in industrial sectors dealing with toxic substances is on the rise. However, conventional gas-sensing systems have limitations in monitoring fugitive gas leakages at both critical and subcritical concentrations in complex environments. To overcome these difficulties, recent studies in the field of gas sensors have employed techniques such as mobile robotic olfaction, remote optical sensing, chemical grid sensing, and remote acoustic sensing. This review highlights the significant progress made in various technologies that have enabled accurate and real-time mapping of gas distribution and localization of hazardous gas sources. These recent advancements in gas-sensing technology have shed light on the future role of gas-detection systems in industrial safety.