• 한국진공학회:학술대회논문집
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• 한국진공학회 2005년도 제29회 학술발표회 초록집
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• pp.183-183
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• 2005

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.150.1-150.1
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• 2010

가스 하이드레이트는 물분자와 저분자량의 가스분자가 고압과 저온에서 수소결합을 이루며 형성되는 결정성 화합물을 말한다. 최근 가스 하이드레이트의 물리적 특성과 형성 원리를 이용하여 다양한 분야로의 적용 연구가 수행되고 있는데 이의 효과적 달성을 위해서는 가스 하이드레이트의 상평형 연구가 필수적이다. 기존에 수행되는 상평형 실험 방법은 온도의 변화에 따라 하이드레이트를 해리시키고 압력의 변곡점을 찾는 것으로 최소 24시간이 소요되지만, 본 연구진이 제안하는 QCM을 이용한 방법은 1 ng의 무게에 1 Hz의 변화를 나타내는 수정진동자의 민감성을 이용한 것으로 약 2~3시간 내에 상평형 실험을 수행할 수 있고, 하이드레이트의 기억효과(Memory Effect)를 이용하여 연속적인 상평형 실험도 가능하다. 본 연구에서는 QCM 반응기의 원리 및 실험 방법에 대하여 설명하고 열역학적 촉진제를 첨가한 상평형 실험결과를 제시함으로써 상대적으로 저렴한 가격으로 다양한 촉진제와 억제제 첨가 시 나타나는 상평형 효과를 빠른 시간 내에 선별할 수 있는 방법으로 QCM을 이용한 방법을 제안하고자 한다.

• 공업화학
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• 제7권2호
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• pp.334-340
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• 1996

석탄을 원료로 하는 탄화 시료로 분자체 특성을 지닌 탄소 흡착제를 제조하였다. 변형제를 사용하여 탄소 분자체를 만들었으며, 변형제 농도 변화에 따른 분자체 특성에 관해 연구하였다. 그리고 탄소 분자체의 성능을 측정키 위해 산소와 질소가스를 사용하였으며, Cahn microbalance(D-200)를 사용하여 탄소 흡착제의 흡착 속도를 측정하였다. 이 실험치를 흡착 속도식에 대입하여 탄소 분자체에 따른 가스의 확산도를 구하였으며, 분자체 성능에 대한 변형제 분자량과 농도의 영향을 나타내었다.

• E2M - 전기 전자와 첨단 소재
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• 제9권2호
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• pp.180-187
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• 1996

The use of preformed copolymers and their cross-linking have been attempted in order to improve the intrinsic fragility of monolayers and Langmuir-Blodgett (LB) films and to make their technological applications. It has shown that an imidization followed a polyion-complexation can stabilize the LB films against heat and solvents. And, when the polymer structure was properly designed, concurrent removal of the alkyl tails together with imide formation could be accomplished. In this paper, the monolayers of the polymers which were polyion-complexed with PAA at the air-water interface can be transferred onto solid substrates such as porous fluorocarbon membranes filter and quartz crystal microbalance. The properties of the monolayers and the LB films will be discussed by .pi.-A isotherms, FT-IR, DSC, deposition ratio, QCM, and SEM. In addition, it was attempted to investigate the response characteristics of polymer LB films to the organic gases by the use of QCM.

• 항공우주기술
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• 제2권2호
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• pp.45-49
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• 2003

한국항공우주연구원 위성시험동에 설치된 Bake-Out 챔버를 통하여 과학위성 1호 비행모델(STSAT-1FM)에 대한 Bake-Out 시험이 수행되었다. 본 시험은 시험 후에 장착될 FIMS라는 광학장비에 영향을 미칠 Outgassing Rate의 측정 및 고온에서의 Bake-Out을 통한 오염물질 제거에 목적을 둔 시험으로 총 10일여 동안 시험이 수행되었다. Honeycomb Panel 및 Harness에 대한 시험(Batch 1), 조립된 비행모델에 대한 Bake-Out(batch 2), 그리고 part별로 펼쳐진 상태로의 Bake-Out 시험(Batch 3), 총 세 번의 시험으로 이루어졌다. 각각의 시험에 대하여 TQCM(Thermoelectric Quartz Crystal Microbalance) 및 RGA(Residual Gas Analyzer)를 통하여 Outgassing 물질에 대한 정량적, 정성적 측정 및 분석이 이루어졌다.

• 센서학회지
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• 제16권2호
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• pp.132-141
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• 2007

The purpose this research is to develop QCM (quartz crystal microbalance) biosensor for the determination of haptoglobin. Haptoglobin is an acute-phase protein with a hemoglobin-binding activity and has a potential to be used as a biomarker for infection or cancer. Haptoglobin level in milk has been used for the diagnosis of cow mastitis. In this study, anti-bovine haptoglobin antibody or bovine hemoglobin was chemically immobilized on the surface of the QCM, and the resulting sensor chips were tested for their response to samples containing haptoglobin at different concentrations. Concentration dependent frequency change was observed with both of the sensor chips. Especially, the sensor chip containing anti-bovine haptoglobin antibody showed sufficient sensitivity in the concentrations typically observed in the cows with mastitis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 학술대회 논문집 전문대학교육위원
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• pp.44-47
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• 2000

In the recognition of the gases using the quartz crystal microbalance (QCM) coated with the film materials, it is important to obtain the recognition ability of gases, and the stability of film coated above the QCM. Especially, the thickness of film coated above the QCM is decreased according with the using circumstance and time of QCM gas sensor. Therefore, the sensing characteristics of film is changed with these. In this paper, we coated the lipid PC (Phosphatidyl Choline) materials varing with the blended amount of PVC(Poly Vinyl Chloride) and solution (Tetra Hydrofan:THF) above QCM to obtain the sensitive and the stability of lipid PC film. QCM gas sensors coated with film materials were measured the frequency change in the chamber of stationary gas sensing system injected 1-hexane, ethyl acetate, ethanol and benzene of $20{\mu}{\ell}$, respectively. We also measured the degradation characteristics of QCM gas sensor to show the properties of stability.

• 한국전기전자재료학회논문지
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• 제19권3호
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• pp.246-249
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• 2006

We fabricated self-assembled monolayers(SAMs) onto quartz crystal microbalance(QCM) using viologen, which has been widely used as electron acceptor and electron transfer mediator. We determined the time dependence on resonant frequency shift during self-assembly process and observed the morphology of self-assembled monolayers by STM and investigated the electrochemical behavior of SAMs by cyclic voltammetry. Electrochemical deposition of viologen was investigated using electrochemical quartz crystal microbalance(EQCM). The redox reactions of viologen were highly reversible and the EQCM has been employed to monitor the electrochemically induced adsorption of SAMs during the redok reactions. The total frequency change was about 9.5 Hz, and 7.1 Hz. From the data, we could know the mass change was about 10.16 ng and 7.60 ng, respectively. Finally, the EQCM has been employed to monitor the electrochemically induced adsorption of self-assembled monolayers on Au surfaces.

• Environmental Engineering Research
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• 제24권4호
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• pp.600-607
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• 2019

Volatile organic compounds (VOCs) are released from various sources and are unsafe for human health. Porous materials are promising candidates for the adsorption of VOCs owing to their increased ratio of surface area to volume. In this study, activated carbon (AC) impregnated cellulose acetate (CA) electrospun mats were synthesized using electrospinning for the removal of VOCs from the air mixture of ACs, and CA solution was electrospun at different proportions (5%, 10%, and 15%) in a single nozzle system. The different AC amounts in the electrospun mats were distributed within the AC fibers. The adsorption capacities were measured for acetone, benzene, and dichloromethane, using quartz crystal microbalance. The results elicited an increasing adsorption capacity trend as a function of the impregnation of ACs in the electrospun mats, while their capacities increased as a function of the AC concentration. Dichloromethane resulted in a faster adsorption process than acetone and benzene owing to its smaller molecular size. VOCs were desorbed with the N₂ gas purging, while VOCs were adsorbed at higher temperatures owing to the increased vapor pressures. The adsorption analysis using Dubinin-Astakhov equation showed that dichloromethane is more strongly adsorbed on mats.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.23-27
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• 2003

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electrodes as well as micellar assemblies, which can be profitably utilized for display devices, photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator. Fromherz et al studied the self-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface. The electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency$({\Delta}F)$ and resonant resistance(R). The redox process of viologen was observed with resonant frequency $({\Delta}F)$.