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Characteristics of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) with light-emitting wavelength around 265 nm are investigated by inserting a higher Al-content AlGaN layer within the multiple quantum wells (MQWs). It is found that there is a significant enhancement of light output power (LOP) and efficiency droop for DUV-LEDs with the inserted higher Alcontent AlGaN layer compared to those with the conventional one. The location of the AlGaN layer with higher Al-content in the MQWs is proven to greatly affect the distribution of carriers and the overlap of electron and hole wave functions. The optimal structure can be achieved when the higher Al-content layer is placed on the right side within the MQWs. The key factors for the performance improvements for this specific design is the enhanced hole transport and reduced electron leakage.

ntroduced the types of chassis dynamometer and accounted for work process of the eddy current dynamometer. We designed the three isometric for low-speed and high-power wheeled vehicles ,which to solve the three-axis dynamometer.Based on the optimized platform ,we established a dynamic model to analyze.In addition.We also optimized the test-control software,and simplified the measurement in process,to achieve a goal in good which is to detect the dynamic capability for a certain type of wheeled vehicle.

The anti-reflective SiO2 film on glass was prepared by sol-gel process and dip-coating method.The effect of drawing speed on properties of the SiO2 film was studied. The transmittance was tested by light spectrum transmittance testing system,the thickness and refractive index of SiO2 film was tested by spectroscopic ellipsometer. With increasing of the drawing speed from 100mm/min to 300 mm/min, the average of transmittance increment at first increased and then decreased, which reached the maximum 4.24% at the speed 150mm/min. The relations among transmittance, thickness (d) and refractive index (n) of the SiO2 film was dicussed.