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 : R.M. Issa (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Phosphoric acid and pH sensors based on polyaniline films
M.M. Ayad,N.A. Salahuddin,M.O. Alghaysh,R.M. Issa 한국물리학회 2010 Current Applied Physics Vol.10 No.1
Polyaniline (PANI)-chemically coated the electrode of quartz-crystal microbalance (QCM) has been developed for the determination of phosphoric acid (H3PO4) in the liquid phase. The sensing mechanism is based on the fact that the QCM devices produce a change in the oscillating frequency when the PANI coating the electrode of QCM interacts with different concentration of the acid. This was made during the subsequent redoping.dedoping processes of the PANI film in acid and ammonia solutions, respectively. Also,this was made during the successive redoping in different acid solutions. The QCM sensor demonstrated a rapid response to the acid with an excellent reversibility. A linear response of the sensor for different concentrations of H3PO4 was found in region of ≤1 M. The conductivity at different concentration of the acid was also determined. Finally, pH dependence on the electronic absorption of PANI phosphate film was studied which indicates that the film can be used as a sensor over a wider pH range of 3.12. This is in comparison to a PANI-sulphate film which shows limited pH absorption dependence (5.8).
-
Issa, A.O.,Igwe, K.N.,Akangbe, B.R.,Aliyu, M.B. Korea Institute of Science and Technology Informat 2014 Journal of Information Science Theory and Practice Vol.2 No.3
This study investigated the information environment of lecturers in Federal Polytechnic, Offa, Kwara State, Nigeria, in relation to their information seeking behavior, extent of use of the polytechnic library, perceptions of the resources and services of the library, level of awareness and extent of use of the open access model of scholarly communications, as well as the challenges of accessing and using information resources. It adopted the survey research method, using a questionnaire for data collection, while the descriptive statistics method was used to analyse the data, using tabular presentation and simple percentages. From a population of 280 lecturers for the study, a purposive sample of 164 was drawn. The findings showed that the lecturers' information needs are focused on online use; they hardly use the polytechnic library due to their perceptions of the resources and services of the library. They are, to a greater extent, aware of open access initiatives, but do not publish in open access outlets, while various challenges affect their access and use of information resources for teaching and research. A recommendation was made, among others, that the polytechnic management should pay more critical attention to the library especially in the areas of adequate, current and comprehensive collections on all the programmes of the institution, as well as the provision of wireless internet services on the campus through a public-private partnership arrangement.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
