• 접착 및 계면
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• 제13권2호
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• pp.85-88
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• 2012

In this paper, the curing reaction of UF resins was investigated by a real time FT-IR method. The curing temperature range of the UF resin was $25{\sim}200^{\circ}C$. It was found that the reactions of UF resin at different temperatures resultedin resins with different cross-linked structures. A real time FT-IR spectroscopy can be considered as a good routine analytical tool for following the progress of UF resin curing.

• Elastomers and Composites
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• 제52권4호
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• pp.266-271
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• 2017

This study describes the influence of the amount of curing agent and curing temperature on the kinetics of polyurethane elastomers. The urethane prepolymer series was prepared by reacting toluene diisocyanate with polytetramethylene ether glycol at $80^{\circ}C$ for 1 h, and 4,4'-methylene bis(2-chloroaniline) was used as the curing agent. The ratio of the amine group of the curing agent to the isocyanate group of the urethane prepolymer was controlled from 0.85 to 1.05 at curing temperatures ranging from 80 to $120^{\circ}C$. The curing rate of the urethane prepolymer was monitored by observing the change in heat flow during the curing process using differential scanning calorimetry (DSC). As either the content of curing agent or the curing temperature was higher, the conversion rate to the polyurethane elastomer was high. The DSC results were compared with those obtained from using real-time FT-IR.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1114-1118
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• 2008

In previous fire accident of railway car, the fatality was relatively high by toxic gas poisoning cause of closed space. So the necessity of quantifying toxic gas in combustion gas was recognized and then, FT-IR spectroscopy was introduced for real-time analysis of mixed gases and stimulated analysis of the concentration of several gases. Thus, in this study, absorption bands using FT-IR were obtained by each component of combustion gases for interior materials of railway car such as flooring materials and moquette seat. And then the sample spectra were compared with the spectra of NO, $NO_2$, $SO_2$ reference gases, we could obtain some identical peaks of them.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.367-370
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• 2000

In this study, thin films of 70/30 and 80/20 mol% P(VDF-TrFE) copolymers were fabricated by physical vapor deposition method. In order to determine the optimum deposition condition, the copolymer thin films were fabricated in the heating temperature of 260$^{\circ}C$, 280$^{\circ}C$, and 300$^{\circ}C$. The deposition rate was measured in a real time by thickness monitor. The surface image of prepared thin films was analyzed by using AFM. From the results of TG-DTA,70/30 and 80/20 mol% P(VDF-TrFE) copolymers were observed the Curie transition point below the melting point. As the results of AFM and FT-IR analysis, we determined that the optimum deposition temperature was 300$^{\circ}C$.

• 분석과학
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• 제27권2호
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• pp.108-113
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• 2014

휘발성 유기 화합물(VOC)은 상온에서 가스 상태로 있거나 가스 상태가 되기 쉬운 화합물로써 유해화학물질관리법으로 관리되고 있는 유해물질이다. 이러한 휘발성 유기 화합물을 측정하기 위해서 일반적으로 측정자가 직접 현장에서 포집하는 방법을 채택하고 있으나, 이 방법은 측정자가 위험에 노출될 수 있으며, 측정자의 접근이 제한적이거나 대공간일 경우 측정이 어려운 단점을 가진다. 특히 대공간에서 포집하는 경우 샘플링에서 오는 오차 및 대공간에서 샘플링의 대표성을 확보하지 못하는 단점을 가지며, 넓은 공간을 연속하여 실시간 측정이 불가능한 점도 간과할 수 없다. 이러한 문제점을 해결하기 위하여 본 연구에서는, 주로 대기오염 등의 모니터링에 부분적으로 연구되어온 개방형적외선분광기(open path FT-IR spectrometer)를 사용하여 원거리에서 대용량, 실시간 측정을 시도하였다. 우선 VOCs 중 벤젠을 대상으로, 시스템과 VOCs 시료와의 분석 최적거리를 측정하였으며, 확인 결과 15 meter에서 가장 좋은 흡광강도(absorption intensity)를 확인하였다. 15 meter의 최적거리에서 휘발되는 7종의 VOCs를 원거리 정성분석하였으며, 벤젠을 대상으로 정량 분석을 시도하였다. 본 연구를 통해 기존에 분석방법으로 불가능하였던 대공간 VOCs의 측정 및 상시 모니터링의 가능성을 확인할 수 있었다.

• 한국전기전자재료학회논문지
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• 제35권2호
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• pp.149-154
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• 2022

In this paper, laser-induced fluorescence properties of four plastics were characterized through spectrometer analysis for real-time microplastic counting. Recently, environmental problems related to microplastics have emerged. In order to detect microplastics, analysis methods such as FT-IR and Raman are used. However, they have the disadvantages of being time-consuming and requiring a pretreatment process. In most plastic products on the market, 10% to 30% of plasticizers and reinforcing agents are added. Therefore, most microplastics present in seawater and freshwater emit fluorescence signals by 270 nm UV light source regardless of their type due to their molecular structure due to additives. Real-time microplastics counting is possible more easily by using the proposed laser-induced fluorescence detection method because of the fluorescence expression characteristic of 340 nm that appears due to the plasticizer of plastics.

• 접착 및 계면
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• 제4권4호
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• pp.22-27
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• 2003

탄소나노튜브(CNT)의 분산성을 개선하기 위하여 $HNO_3$와 $H_2SO_4$를 사용하여 표면을 개질하였고, 적외선 분광법(FT-IR)과 산-염기 적정법을 통하여 CNT의 표면에 카르복실산이 도입된 것을 확인하였다. CNT의 분산성을 확인하기 위하여 초음파를 이용하여 톨루엔, 디메틸포름아마이드 (DMF) 및 N-메틸피롤리돈(NMP) 등의 유기용매에 개질 전(rCNT) 및 개질 후(mCNT)를 각각 분산시키고, 실시간 광학현미경(real-time video microscope)으로 분산거동을 관찰하였다. rCNT에 비해 mCNT가 극성이 큰 DMF 및 NMP 용매에 분산이 잘 되었으며 비극성인 톨루엔에는 분산성이 나쁨을 알 수 있었다. 또한, DMF에 CNT를 분산시킨 후, 폴리메틸메타크릴레이트(PMMA)를 용해시키고 이를 필름으로 제조한 후 주사전자현미경(SEM)을 통하여 분산형태를 관찰한 결과 mCNT의 분산성이 우수하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1220-1223
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• 2003

The UV nanoimprint technology uses the UV light as the energy source. Because the imprint process is carried out in room temperature and low pressure, this technology has its own merits compared to the thermal nanoimprint. However, in UV nanoimprint technology, a resin which has low viscosity is essential for the improvement of accuracy. In this research, a resin (named as IMS01) which has relatively low viscosity was developed. And a measurement system was developed in order to measure the degree of cure of the resin. The measurement system which is composed of FT-IR, UV light source and optical guide can measure the degree of cure in real time. From the experimental results, it was found that the IMS01 is cured more rapidly than existing resin (PAK01).

• Mycobiology
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• 제45권2호
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• pp.73-83
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• 2017

The ability of dead cells of endophytic Drechslera hawaiiensis of Morus alba L. grown in heavy metals habitats for bioremoval of cadmium ($Cd^{2+}$), copper ($Cu^{2+}$), and lead ($Pb^{2+}$) in aqueous solution was evaluated under different conditions. Whereas the highest extent of $Cd^{2+}$ and $Cu^{2+}$ removal and uptake occurred at pH 8 as well as $Pb^{2+}$ occurred at neutral pH (6-7) after equilibrium time 10 min. Initial concentration 30 mg/L of $Cd^{+2}$ for 10 min contact time and 50 to 90 mg/L of $Pb^{2+}$ and $Cu^{2+}$ supported the highest biosorption after optimal contact time of 30 min achieved with biomass dose equal to 5 mg of dried died biomass of D. hawaiiensis. The maximum removal of $Cd^{2+}$, $Cu^{2+}$, and $Pb^{2+}$ equal to 100%, 100%, and 99.6% with uptake capacity estimated to be 0.28, 2.33, and 9.63 mg/g from real industrial wastewater, respectively were achieved within 3 hr contact time at pH 7.0, 7.0, and 6.0, respectively by using the dead biomass of D. hawaiiensis compared to 94.7%, 98%, and 99.26% removal with uptake equal to 0.264, 2.3, and 9.58 mg/g of $Cd^{2+}$, $Cu^{2+}$, and $Pb^{2+}$, respectively with the living cells of the strain under the same conditions. The biosorbent was analyzed by Fourier Transformer Infrared Spectroscopy (FT-IR) analysis to identify the various functional groups contributing in the sorption process. From FT-IR spectra analysis, hydroxyl and amides were the major functional groups contributed in biosorption process. It was concluded that endophytic D. hawaiiensis biomass can be used potentially as biosorbent for removing $Cd^{2+}$, $Cu^{2+}$, and $Pb^{2+}$ in aqueous solutions.

• 대한금속재료학회지
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• 제49권1호
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• pp.46-51
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• 2011

Real-time formation of $L1_0$ phase of FePt nanoparticles in the gas phase during ultrasonic-spray pyrolysis is first discussed in the present study. Without any post heat treatment, $L1_0$ phase of FePt nanoparticles appeared at the temperature above $900^{\circ}C$ in the gas phase synthesis. X-ray diffractometry (XRD) and transmission electron microscopy (TEM) studies revealed that FePt nanoparticles less than 10 nm in size contained small volume of $L1_0$ fct phase. However, in other samples obtained at the temperature below $900^{\circ}C$, iron oxide phase co-existed and no evidence of phase transformation was found. Thus, it is anticipated that the time of flight of particles required for crystallization and phase transformation was extended according to the increase of the collision rate. Finally, magnetic properties represented by coercivity and saturation magnetization and functional groups on the particle surface were discussed based on VSM and FT-IR results.