Detail of "109-67-1"

Reference

Studies on the improvement of sensitivity and stability of fiber optic oxygen sensing based on cladding fluorescence

Studies on the improvement of sensitivity and stability of fiber optic oxygen sensing based on cladding fluorescence. Vishnoi, Gargi; Morisawa, Masayuki; Mizukami, Tatsuya; Uchiyama, Koji; Muto, Shinzo (Department of Electrical Engineering and Computer Science, Faculty of Engineering, Yamanashi University, Kofu 400, Japan). Proceedings of SPIE-The International Society for Optical Engineering, 3105(Chemical, Biochemical, and Environmental Fiber Sensors IX), 114-121 (English) 1997 SPIE-The International Society for Optical Engineering. CODEN: PSISDG. ISSN: 0277-786X. DOCUMENT TYPE: Journal CA Section: 79 (Inorganic Analytical Chemistry) Section cross-reference(s): 36, 73 An attempt was made to improve the sensitivity and stability of optical fiber sensor used for the continuous monitoring of gaseous O. It uses the quenching phenomena of cladding fluorescence. Two polymers viz. Poly Cyclohexyl Methylacrylate (PCMA) and Poly (4-Methyl-1-Pentene) (PMP) were selected which were doped with 9,10-Di-Ph-Anthracene (DPA) and sensor head was prepd. by dipcoating the polymer on a 4.2 cms length of an esp. designed ARTON plastic fiber with 1 mm core diam. For dipcoating, polymer matrix contg. 3% wt. of fluorescent dye was used. The sensor head thus prepd. was tested for various O concns. varied by mixing N. D2-lamp was used for UV side pumping and thus the fluorescence generated in the cladding was coupled to another plastic optical fiber at the output end. The change in fluorescence due to O content was recorded using a photo-multiplier at the l = 430 nm. The results obtained were tabulated as comparative studies. The response is fast, reversible and reproducible with recovery time of the order of few seconds in both the cases. The sensors detect a wide range of O concn. ranging from 0.5% to 100% of O2. In the case of PCMA, better stability in long-term was obsd. The effect of cladding thickness on the sensor performance was also explored.

1-Pentene epoxidation in titanium silicalite-1 microchannel reactor

1-Pentene epoxidation in titanium silicalite-1 microchannel reactor. Experiments and modelling. Wan, Y. S. S.; Gavriilidis, A.; Yeung, K. L. (Department of Chemical Engineering, Hong Kong University of Science and Technology, Hong Kong, Peop. Rep. China). Chemical Engineering Research and Design, 81(A7), 753-759 (English) 2003 Institution of Chemical Engineers. CODEN: CERDEE. ISSN: 0263-8762. DOCUMENT TYPE: Journal CA Section: 27 (Heterocyclic Compounds (One Hetero Atom)) A TS-1 coated, microchannel reactor was fabricated onto silicon substrate using selective seeding and regrowth. The prepn. technique's ability to engineer the zeolite film microstructure and chem. was used to prep. TS-1 coatings with different titanium-contents and crystal sizes. The zeolite microreactor was utilized for 1-pentene epoxidn. to 1,2-epoxypentane with hydrogen peroxide. This exothermic reaction can benefit by good heat transfer and containment of the oxidizing agent. A computational model was employed to simulate the reaction in the microreactor using kinetic data from batch reactor expts. The influence of reactor geometry, catalyst properties and reaction conditions was evaluated and the results compared with exptl. data.