On the basis of the data of hydraulic fracturing stress measurement and mechanical property of the drilledcore from the Maoping 800 m bore hole, the failure mechanism of disk core in the bore hole was analysed. Inthis...On the basis of the data of hydraulic fracturing stress measurement and mechanical property of the drilledcore from the Maoping 800 m bore hole, the failure mechanism of disk core in the bore hole was analysed. Inthis paper, it is considered that the disk core is caused by the declination of principal axis of crustal stress under low crustal stress value. According to the section property of disk core and stress analysis, the form of disk core is tensile failure.展开更多
We theoretically study the nonlinear compression of a 20-rnJ, 1030-nm picosecond chirped pulse from the thin-disk amplifier in a krypton gas-filled hollow-core fiber. The chirp from the thin-disk amplifier system has ...We theoretically study the nonlinear compression of a 20-rnJ, 1030-nm picosecond chirped pulse from the thin-disk amplifier in a krypton gas-filled hollow-core fiber. The chirp from the thin-disk amplifier system has little influence on the initial pulse, however, it shows an effect on the nonlinear compression in hollow-core fiber. We use a large diameter hollow waveguide to restrict undesirable nonlinear effects such as ionization; on the other hand, we employ suitable gas pressure and fiber length to promise enough spectral broadening; with 600-μm, 6-bar （1 bar = 105 Pa）, 1.8-m hollow fiber, we obtain 31.5-fs pulse. Moreover, we calculate and discuss the optimal fiber lengths and gas pressures with different initial durations induced by different grating compression angles for reaching a given bandwidth. These results are meaningful for a compression scheme from picoseconds to femtoseconds.展开更多
文摘On the basis of the data of hydraulic fracturing stress measurement and mechanical property of the drilledcore from the Maoping 800 m bore hole, the failure mechanism of disk core in the bore hole was analysed. Inthis paper, it is considered that the disk core is caused by the declination of principal axis of crustal stress under low crustal stress value. According to the section property of disk core and stress analysis, the form of disk core is tensile failure.
基金Project supported by the National Basic Research Program of China(Grant No.2011CB808101)the Funds from the Chinese Academy of Sciences,and the National Natural Science Foundation of China(Grant Nos.11127901,10734080,61221064,60908008,and 61078037)
文摘We theoretically study the nonlinear compression of a 20-rnJ, 1030-nm picosecond chirped pulse from the thin-disk amplifier in a krypton gas-filled hollow-core fiber. The chirp from the thin-disk amplifier system has little influence on the initial pulse, however, it shows an effect on the nonlinear compression in hollow-core fiber. We use a large diameter hollow waveguide to restrict undesirable nonlinear effects such as ionization; on the other hand, we employ suitable gas pressure and fiber length to promise enough spectral broadening; with 600-μm, 6-bar （1 bar = 105 Pa）, 1.8-m hollow fiber, we obtain 31.5-fs pulse. Moreover, we calculate and discuss the optimal fiber lengths and gas pressures with different initial durations induced by different grating compression angles for reaching a given bandwidth. These results are meaningful for a compression scheme from picoseconds to femtoseconds.
