• Current Photovoltaic Research
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• 제10권2호
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• pp.49-55
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• 2022

With rapid growth in light-harvesting efficiency from 3.8 to 25.8%, organic-inorganic hybrid perovskite solar cells (PSCs) have attracted great attention as promising photovoltaic devices. However, despite of their outstanding performance, the commercialization of PSCs has been suffered from severe stability issues, especially for UV and humidity: (i) UV irradiation towards PSCs is able to lead UV-induced decomposition of perovskite films or catalytic reactions of charge-transporting layers, and (ii) exposure to surrounding humidity causes irreversible hydration of perovskite layers by the penetration of water molecules, resulting considerable decrease in their power-conversion efficiency (PCE). This review investigates current status of strategies to enhance UV and humidity stability of PSCs in terms of UV-management and moisture protection, respectively. Furthermore, the multifunctional approach to increase long-term stability as well as performance is discussed as advanced research directions for the commercialization of PSCs.

• 약학회지
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• 제28권6호
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• pp.299-303
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• 1984

In order to eluciate the effect of humidity and organic solvent on the decomposition of carbamide peroxide, the kinetic study was carried out. The carbamide peroxide was prepared from urea and 30%-hydrogen peroxide. The accelerated stability analysis for carbamide peroxide crystal in various relative humidity, and for 10%-carbamide peroxide solution of organic solvents were investigated. Both humidity and temperature were important factors influencing the decomposition rate of carbamide peroxide crystal. The higher the humidity and temperature, the greater was the reaction rate. The breakdown rate of crystal was observed as an apparent zero-order, and was faster than the rate of decomposition in dilute propylene glycol, glycerine or sorbitol solutioos which were measured as an apparent first-order reaction. The more dilute to 10% the organic solvents of 10%-carbamide peroxide, the slower was breakdown rate. It is, therefore, useful in the aspects of stability and economics to substitute solvent of carbamide peroxide topical solution (USP XXI) with 10%-propylene glycol or glycerine instead of anhydrous glycerine.

• 보존과학회지
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• 제27권1호
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• pp.91-100
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• 2011

본 연구에서는 열화된 소나무류를 대상으로 PEG 처리 후 조습건조시 적정 PEG농도, 습도 및 시간을 조사하고자 하였고, 조습건조과정 중 치수안정화 효과를 진공동결건조 및 자연건조한 것과 비교하였다. 조습건조에서 PEG의 농도가 높을수록 건조시간이 단축되었으며 치수안정성이 우수하였다. 저농도(40%, 50%) PEG 함침 후 조습건조는 치수안정화 효과가 적었고 목재표면 및 내부에 갈라짐이 발생하였으며 PEG의 분포가 불균일하였다. 고농도(60%, 70%) PEG 함침 후 조습건조를 하였을 때 목재의 표면은 흑화현상으로 인해 색은 어두워졌으나, 저농도(40%) PEG 함침 후 진공동결건조한 것과 비교하여 거의 동일한 치수안정화 효과를 나타내었다. 따라서 대형발굴수침고목재의 보존처리시 진공동결건조가 불가능할 경우 고농도 PEG(70%) 함침 후 조습건조하는 방법이 가능하고, 이때 건조습도와 건조시간을 충분히 고려해서 건조해야 함을 알 수 있었다.

• 공업화학
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• 제10권3호
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• pp.461-466
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• 1999

암모늄염을 포함하는 고분자 습도센서를 2-methacryloxyethyl dimethyl 2-hydroxyethyl ammonium bromide (MDHAB)/MMA/DAEMA=6/3/1의 공중합체로부터 제조하였다. 감습막은 금/알루미나 전극에 침적법에 의하여 도포하였으며 $5^{\circ}C$, 40%RH, 70%RH, 그리고 90%RH에서 전형적인 임피던스는 각각 $298k{\Omega},\;11k{\Omega}$, 그리고 $2.3k{\Omega}$을 나타내어 감습특성은 저온에서 사용되는 습도 센서로서의 특성에 적합하였다. 온도 의존성 계수는 $5{\sim}20^{\circ}C$에서 $-0.80%RH/^{\circ}C$이었으며 히스테리시스는 ${\pm}2%RH$ 이내에 존재하였다. 응답 속도는 34%RH에서 88%RH로 변화할 때 38초였다. 신뢰성 시험으로서 온도 사이클, 습도 사이클, 고온 고습 저항성, 전기 인가, 장기 방치, 그리고 내수성을 측정하여 습도센서로서의 응용성을 평가하였다.

• 한국산업보건학회지
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• 제7권1호
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• pp.21-31
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• 1997

Toluene, n-hexane, and methyl ethyl ketone(MEK) were exposed to the activated carbon fiber(ACF) and 3M(Model 3500) diffusive samplers under low and high humidity levels. In order to evaluate these two samplers, the sampling capacity, sampling rate, reverse diffusion, and storage stability were obtained. At low humidity level($8{\pm}3%RH$), the adsorption amount of all three organic vapors to the ACF diffusive sampler showed a positive linear relationship up to 8 hours. However, at high humidity level($90{\pm}5%RH$), n-hexane and MEK maintained a positive linear relationship up to 1.5 hrs, but decreased in their adsorption amounts afterwards. On the other hand, the adsorption amount of n-hexane, MEK, and toluene to 3M diffusive sampler showed almost a positive linear relationship up to 8 hours at both humidity levels. At low humidity level, there was almost no reverse diffusion for both 3M and ACF diffusive samplers. However, when the ACF diffusive sampler was used at high humidity level, there was about 52.63% of MEK sample loss and about 92.59% of n-hexane sample loss. The storage stabilities of the ACF and 3M diffusive samplers were both relative stable except for MEK. In the case of MEK, the difference between the analysis of the organic vapor right after the sampling and that of 3 weeks later at room temperature was 45% for the ACF diffusive sampler and 18% for the 3M diffusive sampler. Since the storage stability of the samples stored in a refrigerator was relatively stable, they need to be refrigerated until the analysis is done.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.421-424
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• 1996

Effects of humidity absorbing deterioration on AC dielectric breakdown characteristics of modified epoxy resin system with SN(succinonitrile) were investigated. As the forced humidity absorbing deterioration proceeded under high temperature and humidify, glass transition temperature increased. The dielectric breakdown strength increased and then decreased at deterioration cycles higher than 2. Not only, the increment of thermal stability but also, the physical detects such as Internal cracks and voids occurred during the humidity absorbing deterioration cycle were the main causes of the change in dielectric properties.

• Macromolecular Research
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• 제13권2호
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• pp.96-101
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• 2005

Thin-film humidity sensors were prepared using inorganic/organic hybrid polyelectrolytes, which were prepared from the sol-gel reaction of copolymers of [2-(methacryloyloxy)ethyl]dimethylpropylammonium bromide (MEPAB), n-butyl methacrylate (BMA), and 3-(trimethoxysilyl)propyl methacrylate (TSPM) with tetraethyl ortho-silicate (TEOS). The humidity-sensitive polyelectrolytes were composed of the copolymers having the following mole ratios of MEPAB, BMA, and TSPM: 60/30/10, 55/30/15, and 50/30/20. We found that the impedance varied with the content of MEPAB or TEOS; it ranged from $10^{7} to 10^{3}\Omega$ between 20 and $95\%$ relative humidity, which is the range required for a humidity sensor operating at ambient humidity. In addition we investigated a number of characteristics of these humidity sensors, such as their hysteresis, response time, temperature dependence, frequency dependence, water durability, and long-term stability.

• 약학회지
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• 제40권4호
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• pp.375-381
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• 1996

Five crystal modification of droperidol were prepared by recrystallization. They were characterized by UV spectrophotometer, DSC, and X-ray crystallography. Their dissolution pa tterns were also investigated. After storage of 2 months at 100% humidity, all polymorphic modifications were transformed.

• Applied Science and Convergence Technology
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• 제25권6호
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• pp.124-127
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• 2016

Humidity calibration for a temperature-stable quartz oscillator (TSQO) was investigated to exclude the influences of relative humidity on the TSQO output in order to use the corresponding devices outdoors. The TSQO output is a voltage that is inversely proportional to the electric impedance of the quartz oscillator, which depends on the viscosity and density of the measured gas. The TSQO output was humidity calibrated using its humidity dependence, which was obtained by varying the relative humidity (RH) from 0 to 100 RH% while other conditions were kept constant. The humidity dependencies of the TSQO output were fit by a linear function. Subtracting the change in the TSQO output induced by the change in humidity, calculated with the function from the experimentally measured TSQO output for a range of 0-100RH%, eliminated the influence of humidity on the TSQO output. The humidity calibration succeeded in reducing the fluctuations of the TSQO output from 0.4-3% to 0.1-0.3% of the average values for a range of 0-100RH%, at constant temperatures. The necessary stability of the TSQO output for application in hydrogen sensors was below one-third of the change observed for a hydrogen leakage of 1 vol.% hydrogen concentration, corresponding to 0.33% of the change in each background. Therefore, the results in this study indicate that the present humidity calibration effectively suppresses the influence of humidity, for the TSQO output for use as an outdoor hydrogen sensor.

• 센서학회지
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• 제12권6호
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• pp.241-248
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• 2003

An electrochemical humidity sensor was fabricated with poly(1,5-diaminonaphthalene) film coated on a gap of two splitted gold electrodes, which were made by vacuum deposition. Response currents according to humidity were measured by the potential sweep method and chronoamperometry. The stability of the polymer film was improved by double step chronoamperometry using the applied voltage of ${\pm}0.5$ Vdc. The response time determined by the pulse technique was about ${\sim}50$ msec and the relative standard deviation of current response was within ${\pm}5.0%$. The response current of the film was intrinsically humidity dependent. The film exhibited a non-linear but reproducible response in ordinary range of relative humidity. The linear equations were $I(nA)=0.28{\times}%RH-1.01$ between 10 to 70 %RH and $I(nA)=6.05{\times}%RH-403.21$ between 70 to 90 %RH.