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501.
An Erratum has been published for this article in Applied Organometallic Chemistry 2001; 15(4):317. The preparation of polyzirconoxanes (EG‐PZO) was investigated by a one‐pot reaction of zirconium oxychloride octahydrate with ethylene glycol. Triethylamine was added dropwise into a mixture of zirconium oxychloride octahydrate, ethylene glycol and methanol to give EG‐PZO with a good spinnability and stability to self‐condensation. The 1H NMR spectrum, IR spectrum, analytical data and expanded X‐ray absorption fine‐structure analysis indicated that EG‐PZO consisted of Zr < (OH)2 > Zr linkages as a main chain with pendant 2‐hydroxyethoxy groups, chloro groups and water. The 3Y2O3–97ZrO2 ceramic fibers were prepared by sintering the precursor fibers after the addition of <?tw=97%>Y(acac)3 (acac = acetoacetate) to EG‐PZO. Copy‐<?tw>­right © 2000 John Wiley & Sons, Ltd.  相似文献   
502.
The optical-limiting property of a new cyclic phenylacetylene oligomer was investigated. Toluene solutions of the oligomer contained within a quartz cell were irradiated with the pulse from frequency doubled Nd: Yag laser at 532 nm. At low input fluence, the transmittance of the toluene solution was constant and agreed well with that obtained by spectrophotometer. At high input fluence, the transmittance of the solution above a concentration of 5 wt % decreased with input fluence. The oligomer had an optical limiting property. As the concentration of the oligomer increased from 5 to 20 wt %, the threshold for optical limiting decreased. The threshold was independent of the molecular weight. The optical limiting property was analyzed by the following equation obtained according to the reverse saturable absorption mechanism; log(I0/I) = K(I0 - I) + Ag, where I0 is the input fluence, I is the output fluence, K is a parameter depending on the absorption cross section and the relaxation time, and Ag is the absorbance of the ground state. © 1996 John Wiley & Sons, Inc.  相似文献   
503.
We present an electrochemical-lossy mode resonance (LMR) sensing method that detects refractive indices and electroactive species. The LMR peaks of indium-tin-oxide in the transmittance-wavelength spectra were significantly shifted as the applied potential between 1.0 and −0.5 V at 209 nm/V. The modulation was exploited for sensing the refractive index and electroactive species (ferrocyanide and methylene blue) in two ways: peak-wavelength tracking and potential scanning. The potential-scanning technique produced clear potential LMR peaks in the transmittance-potential spectra for the first time, which were corresponded to the external refractive index. Meanwhile, the limits of detection of ferrocyanide and methylene blue were 7.5 and 25.3 μM, respectively, in peak-wavelength tracking and 18.2 and 20.8 μM, respectively, in the potential scanning technique.  相似文献   
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