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LGJ150/25 steel core aluminum stranded wires were selected as the test wires, and the aeolian vibrations which work in different cycle times of wire that is under the conditions of dry and acidic corrosion were simulated by the self-made test bed. The electronic number of corona discharge of each pre-set conductor was measured, when applying AC high voltage on the wearing wires step by step,so that the corona inception voltages of the conductors could be confirmed. And the effect of the vibration cycle times and environmental conditions on the corona discharge was researched. Taking the sum of all aluminium stands wear area of a pre-set wire as the fretting wearing capacity, the relationship between the wire wearing capacity and the corona discharge was studied. The results indicate that the corona inception voltages of the conductors decrease with the increase of the cycle times and the wires wear capacity. In general, the wear capacity of the acidic corrosion conductors is larger, and its corona inception voltage is lower. Therefore the decrease of the conductor fretting wear can effectively reduce the corona loss of transmission lines and other hazards.

A spectrophotometric method for the determination of ruthenium (III) is described, based on its catalytic effect on the oxidation reaction of switerland pigment with potassium periodate in 0.016 mol/L of hydrogen chloride medium and in the presence of OP emulsifier (p-iso-octyl phenoxy polyethoxy ethanol) at 100 °C. The above reaction is followed spectrophotometrically by measuring the decrease in the absorbance at 608 nm for the catalytic reaction of switerland pigment. The calibration curve for the recommended method was linear in the concentration range over 0.041.0 μg/L and the detection limit of the method for Ru (III) is 0.012 μg/L. The influence of the factors such as acidity, concentration of reactants, reaction time, temperature and co-existing ions on the reaction is discussed. The optimum conditions of reaction are established and some kinetic parameters are determined. The apparent activation energy of catalytic reaction is 100.48 kJ/mol. The relative standard deviation for the determination of ruthenium (III) at the concentration of 0.02 μg/25 mL is calculated to be 2.3 % (n=11). In combination with distilled separation, the method has been successfully applied for the determination of trace ruthenium (III) in some ores and metallurgy proucts with the relative standard deviations (RSD) over 2.9 %3.8 % and the recovery over 98.2 %-103.6 %.

Femtosecond laser ablation based on two-photon absorption was employed to cut ZnO nanorods into uniform ZnO nanoparticles of deep subwavelength size. The fabricated ZnO nanoparticles possess a shorter mean transport length for photons at the emission wavelength and a much smaller scattering cross section at the pump wavelength, leading to highly efficient two-photon-pumped random lasing with a low threshold of ∼8 mJ/cm2. It was demonstrated that the significant enhancement in two-photon luminescence after the irradiation of femtosecond laser pulses could also be utilized for realizing optical data storage.

A method for measuring the birefringence in planar waveguide circuits is theoretically proposed and validated. The method is based on the Mach-Zehnder interference and by measuring the spectral shift due to orthogonal polarization states. The birefringence of a silica waveguide is measured to be 2.33 × 10(-4) at nearby 1550 nm. In addition, the birefringence variations with the wavelength and its dependence on the external stress are investigated with the proposed method experimentally. The results in measuring birefringence demonstrate a high accuracy with the order of 10(-5), a wide dynamic range from 10(-5) to 10(-3), and a characteristic of multi-wavelength evaluation.

We investigated systematically the modification of the two-photon-pumped random lasing (TPPRL) behavior of ZnO nanorods through femtosecond (fs) laser ablation. The excitation wavelength dependence of the TPPRL behavior of ZnO nanorods was measured and the threshold of TPPRL before and after fs laser ablation was compared. With increasing excitation wavelength, a rapid increase in the threshold of TPPRL was observed at ∼720 nm and it offers us the opportunity to significantly modify the two-photon luminescence from ZnO nanorods by fs laser ablation. The excitation wavelength dependence of the threshold was attributed to the wavelength dependence of the mean free path of photons in ZnO nanorods. When the fs laser ablation was carried out at 720 nm, it was found that the improvement in TPPRL could be achieved at excitation wavelengths longer than 620 nm while the TPPRL behavior became deteriorated for excitation wavelengths shorter than 620 nm. If the ablation and characterization wavelengths were chosen to...

The optical trapping and manipulation of magnetic holes (MHs) dispersed in a magnetic fluid is systematically investigated. It is found that the gradient force, which tends to attract MHs to the beam center, can be completely counteracted by the repulsive force between MHs induced by a magnetic field. As a result, a depletion region is created at the laser beam spot for a sufficiently strong magnetic field. This phenomenon can be easily observed for large MHs with a diameter of 11 μm. However, it does not appear for MHs with a smaller diameter of 4.3 μm. It is revealed that the enhancement in the concentration of magnetic nanoparticles in the laser spot region as well as the clustering of these nanoparticles leads to a much stronger interaction between MHs when a magnetic field is applied. Consequently, the magnetic field strength necessary to create the depletion region is significantly reduced. We also find that the trapping behavior of MHs depends strongly on the thickness of the sample cells. For thin...