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A compact dual-band antenna for ISM (2.45GHz) or WiMAX (3.15GHz) applications by low-temperature co-fired ceramic (LTCC) technology is presented in this paper. The proposed antenna is composed of multi-layer structures to reduce the sizes effectively. The simulated results show that the dimensions of the antenna are 11×4.2×1.2mm3, with the 2:1 VSWR impedance bandwidth definition, the lower and upper band have the bandwidth of 80 and 90 MHz. The novel antenna has realized miniaturization and omni-directional radiation patterns across the whole operating frequency band.

Perovskite-type oxides LaFeO3 and YFeO3 were prepared by the citrate method. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), infrared spectrometer (IR), ultraviolet visible spectrometer (UV). The results show that complex oxides LaFeO3 and YFeO3 have stable perovskite structure. The mean particle diameter of YFeO3 is about 30~40 nm, while LaFeO3 is about 50~60 nm. Photocatalytic degradation experiments of azo dye acid red 3B were done using perovskite-type oxides LaFeO3 and YFeO3 as photocatalysts. Dye Acid Red 3B solution with the LaFeO3 and YFeO3 undergone several degradation stages and the photodegradation rates were respectively 68.2% and 90.0% after irradiating 2 hours. The results show that the perovskite-type oxide YFeO3 has better photocatalytic activity, which mainly relates with the factors of position A such as the negative, the electronic structure, ion radius and so on.

A simple, rapid, and environmentally friendly method has been established for the determination of chlorpyrifos residue in green tea by dispersive liquid-liquid microextraction(DLLME) and gas chromatography-flame photometric detection (GC-FPD). Some experimental parameters that influence extraction efficiency, such as the kind and volume of disperser solvents and extraction solvents, extraction time, addition of salt and pH, were investigated. And the optimal experimental conditions were obtained, quantitative analysis was carried out using external standard method. The correlation coefficient of the calibration curves was 0.999 with in 0.05mg/kg to 5 mg/kg. The results showed that under the optimum conditions，the enrichment factors of the chlorpyrifos was about 484, the recoveries for standard addition fell in the range from 91.94% to 104.70% and the relative standard deviations (RSD) was 4.61%. The limit of quantification (LOQ) of chlorpyrifos in green tea was 0.02μg/ml at the signal/noise (S/N) ratio of 3.