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91.
The evolutions of the electron temperatures of Muminum plasmas produced with 0.351 μm laser are simulated by means of one-dimensional hydrodynamic code. The simulations show that the plasma geometry has strong influence on the electron temperature's evolution while the effect of the flux limiter is not so significant. The simulations are in good agreement with the experiments only at some spatial points. A full comparison between the simulations and experiments indicates that the one-dimensional code is not accurate enough to characterize the laser-produced plasmas. A post-processor code based on the hydro code is developed to generate the streak image of the Thomson scattering spectra, which can be directly compared with the experimental data. 相似文献
92.
《Materials Letters》2005,59(2-3):271-275
ZnO nanoparticles doped with nitrogen on surface were prepared by calcinating pure ZnO nanoparticles at 550 and 600 °C in NH3 atmosphere. Uniform N-doped ZnO nanocrystal was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and XPS. A Strong violet photoluminescence (PL) at 400nm was observed at room temperature when excited with 300 nm light, and the emission peak increases with the increase of nitrogen atoms concentration. The violet PL originated from the electron transition from shallow donor levels of oxygen vacancies and doping nitrogen atoms to the top of valence band level. 相似文献
93.
94.
为了提高烟火固体激光器泵浦源Zr/KClO4的泵浦效率,在烟火剂Zr/KClO4中引入具有催化性能、高比表面积、强吸附能力、高强度的碳纳米管(CNTs),借助差热分析技术和光电探测技术研究了碳纳米管对泵浦源用烟火剂Zr/KClO4(60/40)的热分解和光辐射性能的影响。结果表明:CNTs的加入对Zr/KClO4的热分解特性和光辐射能均有显著的影响。随着CNTs添加量的增加,烟火剂的燃烧速率和放热量均逐渐增加,药剂的融化吸热峰减弱,甚至趋于消失,药剂的光辐射能量却呈现出先增加后降低的趋势。当CNTs含量为体系总质量的0.50%时,药剂总光辐射能达到了1830 J·g-1,其中分布在钕(Nd):钇铝石榴石(YAG)激光增益介质的三个强吸收带(590±10)nm,(750±10)nm和(808±10)nm内的有效光辐射能分别提高了41%,25%和31%。 相似文献
95.
GAO Cong QI XiaoBo WEI Sheng ZHANG ZhanWen LI Bo SHI Tao &CHU QiaoMei Research Center of Laser Fusion China Academy of Engineering Physics Mianyang China School of Chemical Engineering Sichuan University Chengdu 《中国科学:信息科学(英文版)》2011,(9)
To fabricate thick-walled hollow glass microspheres(HGMs)for inertial confinement fusion(ICF)targets by sol-gel technology,we investigated the effects of glass composition,blowing agent,refining temperature,pressure and composition of furnace atmosphere on the wall thickness of HGMs by numerical simulation and experiments.The results showed that the residence times of the thick-walled HGMs in the encapsulating and refining phases decreased with the increase of wall thickness of HGMs.As a response to this ch... 相似文献
96.
S. V. Eskin I. D. Kosobudskiy A. B. Zhimalov N. M. Ushakov D. M. Kulbatskiy S. V. German 《Inorganic Materials》2012,48(10):1006-1011
Single-layer antireflective coatings, produced by sol-gel method on soda-lime glass substrates, were studied. Optimal parameters of the silica sols synthesis and coating procedure of the antireflective coatings based on SiO2 nanoparticles on soda-lime glasses for producing composite glasses with high optical transmittance within the visible range of wavelengths were obtained. 相似文献
97.
NaCl induced atmospheric corrosion of ZnAl2Mg2 coated, electrogalvanised (EG) and hot dipped galvanised (HDG) steel was studied using in situ infrared reflection absorption spectroscopy, XRD and SEM. Initial corrosion leads to the formation of Mg/Al and Zn/Al layered double hydroxides (LDHs) on ZnAl2Mg2, due to the anodic dissolution of Zn–MgZn2 phases and cathodic oxygen reduction on Zn–Al–MgZn2, Al-phases and on zinc dendrites. In contrast to EG and HDG, were no ZnO and Zn5(OH)8Cl2⋅H2O detected. This is explained by the buffering effect of Mg and Al which inhibit the ZnO formation, reduce the cathodic reaction and corrosion rate on ZnAl2Mg2. 相似文献
98.
Bowei Chen Xiaojun Wang Shunru Zhang Chengfu Wei Lin Zhang 《Journal of Porous Materials》2014,21(6):1035-1039
In this study, we developed the ZnO aerogel through dispersed inorganic sol–gel method using citric acid as template, which employed the properties of high apparent specific surface areas. According to the results demonstrated by nitrogen adsorption/desorption and field-emission scanning electron microscope measurements, the aerogel produces extremely porous and homogenous material and monolithic mesoporous materials featuring high surface areas (122 m2/g). The thermal stability is investigated through TGA and FTIR, respectively. When the temperature reaches up to 500 °C, all the organic absorption peaks disappear and only ZnO emerges. In summary, the attractive properties of the aerogel promote the potential applications of their nanostructures. 相似文献
99.
100.
不同硅源制备二氧化硅气凝胶的研究进展 总被引:2,自引:0,他引:2
硅源作为溶胶-凝胶法制备二氧化硅气凝胶前驱体的重要组成部分,对获得结构完整、性能优良的二氧化硅气凝胶以及构建满足不同应用需求的二氧化硅气凝胶至关重要。考察了制备二氧化硅气凝胶所用的单一硅源、复合硅源以及功能性硅源对气凝胶的形貌及物理性能的影响,并对3类不同硅源制备二氧化硅气凝胶进行了综述。 相似文献