A highly selective and sensitive chemiluminescence method for the determination of triclosan is proposed. The method is based on the phototransformation of triclosan to a light-emitting precursor in the presence of fluorescein in alkaline medium and the chemiluminescence reaction is then triggered by strong base or oxidants such as N-bromosuccinimide. Based on this reaction an online phototransformation-flow injection manifold was developed, in which the photoreactor comprises a 150-cm-long x 0.8-mm-i.d. piece of PTFE tubing coiled around a 25-W fluorescent lamp, and the phototransformed products were then injected into a carrier stream of borate buffer. After mixing with the oxidant stream the produced light was detected by a photomultiplier. A wide calibration range from 8.0 x 10(-8) to 1.0 x 10(-4) mol L(-1) was obtained under the optimized conditions, and the detection limit was as low as 5.0 x 10(-8) mol L(-1). The whole process of analysis, including the online phototransformation and subsequent chemiluminescence detection, could be completed in 6 min. Most of the foreign substances tested showed high tolerance levels, and the proposed method was directly applied to the determination of triclosan in toothpaste samples without any pre-separation procedure. Figure Schematic representation of the phototransformation of triclosan and subsequent chemiluminescence reaction.

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A robust particle filter (PF) and its application to fault/defect detection of nonlinear system are investigated in this paper. First, an adaptive parametric model is exploited as the observation model for a nonlinear system. Second, by incorporating the parametric model, particle filter is employed to estimate more accurate hidden states for the nonlinear stochastic system. Third, by formulating the problem of defect detection within the hypothesis testing framework, the statistical properties of the proposed testing are established. Finally, experimental results demonstrate the effectiveness and robustness of the proposed detector on real defect detection and localization in images.

In this paper, a cylindrical trimming method is applied to fit the hemisphere, and the total reflectivity on a certain boundary is analyzed through a series of derivations and calculations. An equation that is used to calculate the reflectivity of the trimming cylindrical anechoic chamber is obtained, and obviously, it has no relationship with the spherical coordinate radius r and can be utilized to optimize the trimming size. The proposed scheme of the non-standard anechoic chamber is proved to be a simplified and effective way to optimize the anechoic chamber. An anechoic chamber is constructed to illustrate the correctness of the theory. The simulation results show that S 11 has achieved good results in most frequency bands.