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The toxicity of three kinds of insecticides on the adults of Sclerodermus sichuanensis Xiao and the sublethal effects of insecticides on their reproduction were studied under laboratory conditions, and video tracking capture system (EthoVision 3. 1) was employed to study the search behavior of S. sichuanensis adults. The results showed that Sclerodermus sichuanensis Xiao is the most susceptible one to acetamiprid. Lethal concentration of LC 50 and sublethal concentration (LC 10) values were 7. 71 mg / L and 4. 46 mg / L respectively, and it is susceptible to imidacloprid (11. 22 and 6. 68 mg / L) and cyhalothrin (27. 72 and 9. 36 mg / L) in the second place. After treated by sublethal concentration of LC 10 with acetamiprid, imidacloprid and cyhalothrin, the rate of successful parasitism for parental generation, F 1 and F 2 generation of S. sichuanensis was restrained. After treated with cyhalothrin, the amount of single fecundity of the parental was increased (P ﹤ 0. 05). After treated with acetamiprid and imidacloprid, there was no significant effect on the rate of reproduction of the parental (P ﹥ 0. 05) , but the F 1 generation was greatly affected (P ﹤ 0. 05). After treated by

A high power level ytterbium doped all-fiber laser at 1018 nm is proposed using the resonant cavity with the 125 μmdiameter double cladding fiber. The single mode high output power of 254 W is achieved with the optical-optical conversion efficiency of 81% via optimizing the length of the gain fiber and controlling wavelength of the pumping LD. The amplified spontaneous emission (ASE) is suppressed efficiently and the residual pumped light is dissipated completely, while the signal to noise ratio (SNR, RSN) is more than 35 dB. As the wavelength of the pumping LD changes with the output power, thus affecting the conversion efficiency of the fiber lasers, the wavelength of pumping LD needs to be controlled accurately for obtaining more efficient conversion efficiency. The output power instability is measured in the experiments with the value of less than 0.5% in four hours. The high efficient fiber lasers at 1018 nm with the stable output power can be applied to the tandem pumping high power fiber lasers as the excellent pump source.

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