Silver nanocluster embedded ZnO composite thin film was observed to have an angle-sensitive and fast photovoltaic effect in the angle range from -90° to 90° , its peak value and the polarity varied regularly with the angle of incidence of the 1.064-μm pulsed Nd：YAG laser radiation onto the ZnO surface. Meanwhile, for each photovoltaic signal, its rising time reached -2 ns with an open-circuit photovoltage of -2 ns full width at half-maximum. This angle-sensitive fast photovoltaic effect is expected to put this composite film a candidate for angle-sensitive and fast photodetector.
The optical property and spectroscopy of selected kinds of lubricating oil are studied based on the terahertz time-domain spectroscopy (THz-TDS) in the spectral range of 0.3-1.6 THz. The samples are classified by their characteristics via the near-infrared spectrum. The experimental results reveal that lubricating oil is more sensitive in the range of terahertz than in the near-infrared,and the specific kinds of lubricating oil can be identified according to their different spectral features in the terahertz range. The THz-TDS technology applied to lubricating oil analysis has potentially significant impact on the petroleum field.
We investigate the diffusion interaction and quantitative analysis of zinc dialkyldithiophosphate （ZDDP） mixed with lube base oil （LBO） at different concentrations using terahertz time-domain spectroscopy （THzTDS）.When the concentration exceeds 6.78%,the characteristic absorption peaks exhibit significantly shift,and the absorption coefficient peak value is nonlinear against concentration.Moreover,the absorption coefficients of mixed samples follow the Beer＇s law at a concentration below 6.78%.The quantitative analysis enables a strategy for monitoring the formulation of lubricating oil in real time
