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This paper focuses on the spectral properties and the impact resistances of composite quartz tubes and cerium doped quartz tubes used in the driving optical components of Inertial Confinement Fusion (ICF) laser facility. The spectral transmittances were tested on the selected samples, new composite quartz tube, new cerium doped quartz tube, 14 000 shot composite quartz tube and 14 000 shot cerium doped quartz lamp tube and their spectral properties were compared. It show that the spectral properties of the composite quartz tube and cerium doped quartz tube have all reached spectral index of the high power pulse xenon lamp, and the spectral propeprty of cerium doped quartz tube is about 1% higher than that of composite quartz tube. A composition test of composite quartz tube and cerium doped quartz tube was carried out to verify the tested results.It indicates that the content of metal impurities in cerium doped quartz tube is lower than that of composite quartz tube, which is one of the reasons to explain the phenomenon mentioned above. Finally, the xenon lamp discharge operation was simulated, the impact resistance tests for the composite quartz tube and the cerium doped quartz tube were carried out. The experimental result demonstrates that the shock resistance of the composite quartz tube is about 6% higher than that of cerium doped quartz tube. ? 2016, Science Press. All right reserved.

InGaN/GaN multiple-quantum well(MQW) light-emitting diodes(LEDs) were fabricated,in which a SiO2 current blocking layer(CBL) was inserted underneath the p-pad electrode.Samples were divided into three groups: normal surface,surface roughing,and surface roughing plus side wall etching.Each group had two different structure devices: with and without CBL.In each group,the voltage Vf at 20 mA for the LEDs with a CBL(Vf=3.156,3.282,3.284 V) were slightly higher than those of without CBL(Vf=3.105,3.205,3.210 V).However,the luminous efficiency and the light-output power of the LEDs with CBL were better than those without CBL.At 20 mA current,the output power of the LEDs with a CBL increase 10.20%,12.19%,11.49% compared with those without CBL.It is due to the current spreading effect in CBL devices.The CBL can also reduce parasitic optical absorption in the p-pad electrode.

The demand for coal resources is increasing with economic development in China.But,the rich mineral resources along with the intensive mining activities,which have led to a lot of ecological and environmental problems,such as environmental pollution,ecological destruction and geological disasters.Eco-risk assessment is an important tool for effective ecological environment management with evaluations of the likelihood and degree of harm. Thus,this paper applied landscape eco-risk assessment methods to estimate the level of the opencast mine area eco-risk.But also the ESDA(Exploratory spatial data analysis) methods were used to analyze the spatial association characteristic of landscape eco-risk in mining area.It turned out that those high-risk areas is the core of the spatial distribution of Landscape eco-risk and from high-risk to low-risk present ring features.In addition,high-risk is mainly distributed in the mining industry and city life areas,sources of which are the mining,coal gangue tie up land and city construction activities.Medium-risk are mainly distributed in nature,half natural functional areas,the main sources of which are the city life and the agricultural production activities.Low-risk areas are covered by sparse vegetation,such as shrub and grassland.However,in research areas,vegetation degradation,soil and water loss leads to the regional ecological base quality was poor.So the ecosystems and environmental factors are fragile here.Moreover,the frequent production activities in mining areas cause more serious ecological and environment problems.The risk degree of the artificial area is higher than the half natural area,and the half natural area is higher than the natural area.It is conform to the conventional law of ecological risk level difference.At the same time,based on the ESDA of the landscape eco-risk in opencast mine area,the space correlation of the risk is up to 0.7521,which indicate that the agglomeration features of the risk obviously.Different characteristics of agglomeration provide the basis for the ecological and environment management.Space differentiation study of Landscape eco-risk in this opencast mine area shows that interference are the main driving factors in the high-risk and low-risk areas.But in the medium-risk area,fragile degree is the main driving factors.With the increase of human interference,landscape lost diversity and tend to simplification.The results of the study on the mining area provide certain data support and theoretical basis to environment management.

Scattering effects of clouds and fogs produce the backscattering signal which results in false alarm for laser fuse.Based on the Monte-Carlo technology,cloud-and-fog scattering effects are simulated,and rules of wave shape and peak power of cloud-and-fog scattering echo variable with baseline distance are qualitively given.Results show that peak power and pulse broadening extent of the laser echo goes up with pulse width increasing.However,when pulse width increases to 50 ns,peak power is saturated.Simulated results may provide target discrimination and optimized design of detecting threshold and transmitting pulse width for laser fuse with reference.

GaN-based blue light-emitting diodes were applied bias of-400,-800,-1 200 and-1 500 V electrostatic discharge in human body mode.The electrical and optical parameters of LED were characterized before and after electrostatic discharge stressing with the theoretical analysis of the influence of electrostatic on LED reliability.After human body mode static crack down on the GaN-based blue LED,the I-V characteristic curve changed,the luminous flux reduced,LED's degradation rate was also accelerated.It is deduced that the LED was hit by electrostatic generates secondary defects and melting channel inside the chip.Based on the result of I-V characteristic curve at different temperature,we assumed that the shallow level ionization is dominated in LED,while after static crack down,the deep level ionization is dominant.Therefore,a failure mechanism caused by electrostatic can be deduced as follow.The generation of secondary defects and melting channel,the shallow level/deep level carrier movement and the change of radiative/non-radiative recombination,cause the degradation of LED performance.These find make great efforts to understand the failure mechanism caused by the electrostatic discharge and anti-static design.

The cloud signals can cause severe wobble of tropospheric ozone concentration in the process of differential absorption lidar measurement of ozone concentration,and bring significant errors.A cloud elimination algorithm is presented.The algorithm effectively eliminate tropospheric ozone wobble by interpolating the ozone concentration in cloud height region.The key point of the cloud algorithm is given through expounding its theoretical basis.The key point of the cloud elimination is the discrimination of cloud signal and accurate positioning of the cloud height.The cloud height information is determined by setting the aerosol extinction coefficient threshold according to the characteristics of the cloud extinction coefficient.The cumulative average of retrieved ozone concentration reduces measurement errors caused by noise.The results show that the correction by interpolation algorithm of ozone measurements in cloud region could overcome the wobble of the ozone measurements caused by clouds.

基于六阳极结反向串联型GaAs平面肖特基二极管，设计并实现了0.2 THz大功率二倍频器。肖特基二极管倒装焊接在50m石英电路上。采用电磁场和电路联合设计仿真获得了二倍频器的倍频效率。当入射功率在100 mW时，输出频率在190~225 GHz带内效率大于5%。在小功率（Pin100 mW）和大功率（Pin300 mW）注入条件下，测试了倍频电路的输出功率和倍频效率。在100 mW驱动功率下采用自偏压测试，最大输出功率为14.5 mW@193 GHz，对应倍频效率为14%；在300 mW驱动功率下采用自偏压测试，在188~195 GHz，输出功率大于10 mW，最大输出功率为35 mW@192.8 GHz，对应倍频效率为11%。

In order to detect corona discharge in all weather situations,a three-band optical system worked at three bands of the solar blind UV,visible and the long infrared was designed for the corona detection.To reduce the system volume and improve the performance merits,a co-lens system was used for both the solar blind UV and visible bands,and an independent lens system containing aspheric surfaces and diffraction surface was adopted for the long infrared band to correct monochromatic and chromatic aberrations.Furthermore,the focusing system was designed with a single lens to ensure an excellent imaging in the temperature from-40 ℃ to 60 ℃.The image quality of the system was evaluated,and it is shown that at the temperature of 20 ℃,the MTF at the spatial frequency of 60 lp/mm is greater than 0.37 in the solar blind UV,and greater than 0.35 in the visible band for the whole fields of view;the MTF at the spatial frequency of 20 lp/mm is greater than 0.6 in the long infrared band for the whole fields of view.These results indicate that the system has excellent imaging characteristics at all three bands,and can be used in the detection of corona discharge in all weather situations.

We have discussed the proper gimbal point position in conformal optical system based on the pupil astigmatism criteria.Then,we derive the best position of the aberration correction gimbal point by using aberration correction criteria in rotationally symmetrical system.The result proves the application potential of the aberration correction criteria in conformal optical system design and the dome's image quality has been improved greatly by properly choosing the position of the gimbal point.

Based on powder sintering technology,Yb3+/Al3+ co-doped silica rods are prepared,and the concentration of Yb3+ is up to 12 000 ppm(wt).Then,with the Yb3+/Al3+ co-doped silica rods as core materials,highly doped Large-mode-area Photonic Crystal Fibers(LMA-PCF) are fabricated by stack-draw method.The mode area can reach 550 μm2,and the mode field diameter is 26 μm.The results indicate that the fiber has a broad absorption band in the near infrared wavelength(850~1 033 nm),and the main peak is at the wavelength of 976 nm where the absorption loss is higher than 10 dB/m;when the fiber is pumped by the laser with a wavelength of 971 nm,there exists a Gaussian fluorescence peak in the wavelength range of 1 150~1 125 nm,with a peak value of 1 088 nm and a half-line width of 45 nm.

The integration-test-bed (ITB) device is established for research on inertial confinement fusion(ICF) in China. The single-beam output energy reaches 19.6 kJ successfully when the fundamental frequency emission wavelength is 1053 nm and the pulsewidth is 5 ns. Experimental results of thermal effect of 400 mm* 400 mm aperture slab amplifiers in ITB devices show that the peak-to-valley value d_(PV) of pump-induced wave-distortion of the whole laser chain is about 5.3 lambda, in the revise extension of deformable mirror, when the gain coefficient is 5.28% cm~(-1). Combined with the optimizations of heat management, the thermal recovery time is about 2.5 h, which can satisfy the requirement of 4 h/shot.