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Indium-gallium-zinc oxide thin film transistor(IGZO-TFT) was fabricated using N2O plasma treated SiNx film as gate insulator and room-temperature deposited IGZO film as active layer.Comparing with the conventional IGZO-TFT,the saturation mobility increased from 4.5 to 8.1 cm2·V-1·s-1,threshold voltage reduced from 11.5 to 3.2 V,threshold swing varied from 1.25 to 0.9 V/dec.The trap states in the N2O plasma treated IGZO-TFT is obviously smaller than that in the conventional IGZO-TFT.Our results indicate that using N2O plasma treated SiNx film as gate insulator is an effective approach for improving IGZO-TFT performance.

The eddy covariance(EC) technique is generally regarded as a standard method for crop evapotranspiration measurements.However,the imbalance of energy closure prevails in the EC observations.Evaluating the effect of energy balance closure on EC measurement is critical for improving the accuracy of this method.In this paper,a weighting method(the Lysimeter method) was used as reference to evaluate the effect of energy balance ratio(EBR) on EC evapotranspiration.The results revealed that daytime EBR varied seasonally in the field,where wheat and maize were rotated in the winter and summer,respectively.The EBR was higher in autumn and winter but lower in the spring and summer.For the wheat field,mean daytime EBR varied from 0.26 to 2.84 with an average of 1.15.As for the maize field,EBR varied from 0.19 to 2.59 with a mean value of 0.78.The evapotranspiration(ET) using EC(ETec) was clearly lower than derived by Lysimeter(ETL).The mean ratio of ETec to ETL(ETec/ETL) was 0.61 and 0.50 during the wheat growing season and the maize season,respectively.The ET observed with these two approaches significantly correlated with each other(P 0.01),with their characteristics of seasonal variation performing in a similar manner.The ETec/ETL was found to be proportional to EBR(P 0.01) in both the winter wheat field and the summer maize field.Furthermore,the effect of the leaf area index(LAI) on the relationship between ET ratios and EBR was significant in the even crop field during the entire growing season of winter wheat and the maize growing stage when the LAI was higher than 1.However,the effect was insignificant in the uneven maize field when the LAI was less than 1.On the other hand,friction velocity(u*) exerted a strong impact on EBR and its relationship with ET ratios.EBR was observed to be proportional to u* in both the winter wheat field and the summer maize field.ET ratios were proportional to EBR when u* was small.Nonetheless,the correlation between these two parameters showed recession while u* increasing,especially in summer maize field,ETec/ETL was not significantly correlated with EBR when u* was bigger than 0.3 m/s.Due to the weak turbulent intensity and the large eddy under the condition of low friction velocity,the EC sensor could not catch enough turbulent energy in a limited observation period(30 minutes),which caused lower measured turbulent fluxes and imbalanced energy closure.The results offer a possible way to correct the underestimated ETec using EBR.

Pure Ti films were fabricated by DC magnetron sputtering. The deposition rate, surface roughness, crystal structure and stress of Ti films at different sputtering power were studied. The deposition rate in-creases with the increase of the sputtering power. The AFM images show that the films are compact and smooth, and the minimum RMS is 0.9 nm when the sputtering power is 20 W. The X-ray diffraction results indicate that the Ti films are hexagonal structure. The stress in the Ti films increases firstly and reaches a maximum stress of 945.1 MPa when the sputtering power is 60 W, then decreases with higher sputtering power.

Bottom-gate ZnO thin-film transistors(ZnO-TFTs) were fabricated with Ta2O5 film as the insulator.Ta2O5 film was grown by the radio-frequency magnetron sputtering at room temperature.The thickness of the Ta2O5 layers were 100,85,60,40 nm separately.The effect of the thickness on the performance of the ZnO-TFTs was studied.With the thickness of the insulator decreased from 100,85,60 nm to 40 nm,the field effect mobility increased from 50.5,59.3,63.8 to 71.2 cm2/V·s.The surface morphology of the Ta2O5 films were checked by the atomic force microscope,which showed that the root mean square(RMS) of the Ta2O5 films roughness decreases with decreasing the insulator thickness.The Ion/Ioff ratio and the threshold voltage are changed with the insulator thickness.

In view of pipelines laid in landslide mass,a security monitoring system is proposed.A method for evaluating maximum strain value based on strains of three points on the pipeline is presented.Temperature compensated FBG strain sensors are used in monitoring the strains of pipeline.The strain data of pipeline measured by sensors after 5.12 Wenchuan Earthquake is analyzed.The analysis results show that the earthquake has remarkable impact on landslide,which is proved by large displacement of shallow sliding plane.Strains of the pipeline increase obviously but the total value is less than pre-warning threshold, therefore,the pipeline is under security condition.

The Raman multi-channels lidar developed by Wuhan University is described.The design principles of the whole system and main technical parameters are provided.The methods for retrieving aerosols' optical properties such as atmospheric aerosol extinction coefficient,backscattering coefficient and lidar ratio are presented in detail,and the key part of retrieving the aerosol extinction coefficient is discussed and analyzed.The real-time detections of optical properties for aerosol,cloud and boundary layer in the low-altitude atmosphere are done.The experiments show that the multi-channels Raman lidar system has good performance for detecting the vertical distribution of aerosols in the night and it is reliable.