http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : 채인창 (검색결과 1 건)
-
A study for Humidity Sensor using The Charcteristics of Sensing moisture Polyvinyl alcohol is a common hydrophilic polymer but shows a significant impedance response with changing relative humidity only above 60% RH. Fabricating simply a polyvinyl alcohol film as humidity sensor lacks durability and also shows high impedance. To overcome this problem, cross-linking of polyvinyl alcohol was done with 4-styrene sulfonate (sodium salt) in presence of ferrous ions. The best results as a humidity sensor material were obtained when polyvinyl alcohol was cross-linked with 4-styrene sulfonate in presence of ferrous ions at a temperature of 140℃ for about 1 h and when polyvinyl alcohol, 4-styrene sulfonate (sodium salt hydrate) and FeCl_2·4H_2O were taken in a weight ratio of 10:2:3 respectively. The structure of the polymeric material was established using NMR and infra-red spectroscopy, to be a co-polymeric material in presence of ferrous ions. The polymeric mixture of the three materials made in water was casted on an alumina substrate (size 7.5mm×7.2mm×0.38mm) prefabricated with interdigitated gold electrodes and was cured at a temperature of 140℃. The results demonstrate that the logarithm of the resistance decreased linearly with increase in %RH in a range of 30-92% RH. Other factors viz. stability, sensitivity and response time for the fabricated sensor were also determined, * Polyvinyl alcohol (PVA) is a cheap and common hydrophilic polymer but lacks durability against moisture and shows high impedance. In this paper, several PVA based humidity sensors cross-linking it with m-benzenedisulphonate sodium salt (MBDS) in presence of various electrolytes were prepared. However, cross-linking PVA with MBDS in presence of ferrous ions showed the maximum sensitivity against relative humidity. Best results were obtained when cross-linking was done by curing the film on an alumina substrate, printed with gold electrodes at 150-160℃ and in a weight ratio of 25:5:9 for PVA : MBDS : FeCl_2·4H_2O composition. Dependence of resistance on the relative humidity(RH) showed linearity between 35 to 85%RH. Other factors viz. temperature dependence, response time were also measured. The humidity sensitive characteristice of the sensor did not change even after soaking in water for 100 min.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
