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41.
A Ni-like Mo soft x-ray laser (SXRLs) operating at 18.9nm has been demonstrated by employing a grazing incidence pumping scheme with 120m^3 in the 200ps pre-pulse and 140mJ in the 200fs main pulse. The SXRL gain is estimated to be 1.5-3cm^-1 when a grazing incidence angle of 14° is applied. Numerical simulations are also performed to investigate the dynamics of the ion distribution. It is found that a high intensity at 2.4× 10^14 W/cm^2 of the 200fs main pulse could heat the pre-plasma rapidly to an appropriate temperature for population inversion, and could compensate for the shortage of the total pump energy to a certain extent.  相似文献   
42.
An experiment on a transient nickel-like Mo x-ray laser in the extreme light III (XL III) laser facility is analyzed, based on the two-dimensional hydrodynamic evolutions of a plasma under a non-uniform incident laser. Influences of the pulse duration and intensity on plasma scale length, electron density, temperature, as well as their distributions are investigated, based on which the pre-pulse character and delay time are determined according to the parameters of laser line focus on XLIII. It is found that the optimal intensity of the pre-pulse is 1.0TW/cm2 with a duration of 500ps; a well modified pre-plasma can be obtained after 1.6ns under low quality line focus in the lab.  相似文献   
43.
某型空空导弹控制部件动态测试系统,在测试过程中出现测试数据传输延迟的现象,从而影响了测试结果,为解决这一问题,本文提出了使用反射内存卡建立实时网络系统的方法解决数据传输延时问题。通过使用VMI-5565反射内存卡建立的实时网络系统实现了某型空空导弹控制部件的动态仿真测试,目前该动态测试系统已经成功用于某制导武器动态仿真测试试验中。动态测试系统在使用了反射内存卡建立实时传输网络后,保证了测量数据传输的实时性和准确性,通过实际测试使用,该系统测试效果良好,完全满足科研试验使用要求  相似文献   
44.
We present a comprehensive analysis of coherence properties of the radiation from X-ray free electron laser (XFEL). We consider practically important case when XFEL is optimized for maximum gain. Such an optimization allows to reduce significantly parameter space. Application of similarity techniques to the results of numerical simulations allows to present all output characteristics of the optimized XFEL as functions of the only parameter, ratio of the emittance to the radiation wavelength, . Our studies show that optimum performance of the XFEL in terms of transverse coherence is achieved at the value of the parameter of about unity. At smaller values of the degree of transverse coherence is reduced due to strong influence of poor longitudinal coherence on a transverse one. At large values of the emittance the degree of transverse coherence degrades due to poor mode selection. Comparative analysis of existing XFEL projects, European XFEL, LCLS, and SCSS is presented as well.  相似文献   
45.
We theoretically investigate a 13.9nm Ni-like Ag x-ray laser using a one-dimensional hydrodynamic code coupled with an atomic physics data package. The population inversion is transiently pumped by a grazing incident 0.5ps main pulse irradiating into an optimized plasma, which is generated by a normal incidence 300ps pulse and a subsequent grazing incidence 300ps pulse. The effect of the grazing-incidence angle on the source position of the output x-ray laser is investigated. Near zero deflecting angle is found for the peak output intensity of the Ni-like Ag x-ray lasers, with a small FWHM divergence of 5mrad. It is predicted that saturation can be achieved with a total pump energy of 165mJ.  相似文献   
46.
The water-soluble polysaccharides from plants have attracted ever-increasing attention in the field of food and drug due to their various activities and low toxicity. CBP50-1, as a purified fraction of polysaccharide from the rhizome of Cibotium barometz (CBP), mainly consisted of glucose (55.45%) and xylose (25.27%). CBP50-1 showed excellent antioxidant activity for scavenging 2,2?Diphenyl?1?picryl?hydrazy (DPPH) radical and hydroxyl radical, further inhibiting lipid peroxidation. CBP50-1 significantly improved the survival rate of Caenorhabditis elegans under thermal and oxidative stress. Furthermore, CBP50-1 reduced the paralysis and oxidative damage induced by amyloid-beta (Aβ) and increased the antioxidant enzyme activity in Alzheimer’s disease (AD) model C. elegans CL4176 through c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) signal pathway. Thus, CBP50-1 had a potential application in health industries.  相似文献   
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