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51.
Electrorheological (ER) fluid is one of the popular materials used in smart materials and structures. The material properties of ER fluid can be changed markedly while an external electric field is imposed on ER fluid domain. In this paper, the optical properties of ER suspensions consisting of composite particles dispersed in silicone oil are investigated. Both dc and ac electric fields are utilized to be imposed on ER fluid. The transmissivity of light through ER fluid under various electric fields is detected and analyzed. It is shown that the transmissivity of light increases with the increasing electric field strength and time. The change of transmissivity is caused by the formation of particle chains. The higher the particle concentration, the faster the change occurs. When an ac electric field is applied, the transmissivity can be affected by the frequency of electric field. 相似文献
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A simple and sensitive method for the determination of dimethylsulfide (DMS) and dimethylselenide (DMSe) employing a gas chromatograph–photoionization detector with headspace sampling (HS-GC-PID) was developed. Parameters affecting the HS-GC-PID sensitivity including matrix effect, heating temperature, extraction time and carrier gas flow-rate were optimized. The matrix effect was required for standard addition calibration method for quantification purposes. The method has been validated when rectilinear relationship was between the concentrations of analytes and peak area in the range of 0.2–50 ng mL− 1 for DMSe and 0.5–100 ng mL− 1 for DMS, the correlation coefficients were from 0.995–0.998, and the limits of detection for DMS and DMSe were 25 pg mL− 1 and 48 pg mL− 1, respectively. The proposed method was further applied to quantification of DMS and DMSe in urine samples. 相似文献
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Protic solvents decrease the susceptibility of the thiolate ligand in Co(III) thiolato complexes toward attack by singlet oxygen, but greatly increase the conversion of the peroxidic intermediate to the sulfenato product. 相似文献
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Yanju Wang Xianhong Wang Xiaojiang Zhao Ji Li Zhishen Mo Xiabin Jing Fosong Wang 《Macromolecular rapid communications》2002,23(2):118-121
Conducting semi‐interpenetrating network composites with low conductivity percolation threshold were synthesized from waterborne conducting polyaniline (cPAn) and melamine‐urea resin. A perfect network of cPAn in the composite was observed by means of TEM (see Figure). The conductivity stability of cPAn in water was improved by confining the chain mobility of cPAn via in‐situ crosslinking of melamine‐urea resin. Cyclic voltammetry of the composites reveals electrochemical activities and reversibilities similarly to those of pure cPAn. 相似文献