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91.
92.
采用传统熔融法制备了Na_2O-Y_2O_3-P_2O_5-SiO_2前驱体玻璃,并对前驱体玻璃样品进行热处理,成功合成透明磷酸盐玻璃陶瓷。对玻璃陶瓷样品进行XRD分析确定玻璃基质中有Na_(3.6)Y_(1.8)(PO_4)_3晶体析出。讨论了热处理时间对玻璃陶瓷结晶度和晶粒尺寸的影响,确定热处理温度为655℃,热处理时间为2 h。比较Ho~(3+)单掺和Ho~(3+)-Yb~(3+)共掺玻璃陶瓷上转换发光强度,确定Ho~(3+)与Yb~(3+)的最佳掺杂物质的量之比为1∶2。同时讨论了Ho~(3+)-Yb~(3+)之间的能量转移。使用积分球测得样品的上转换发光量子效率。 相似文献
93.
Role of helium in the sliding and mechanical properties of a vanadium grain boundary:A first-principles study 下载免费PDF全文
The effects of helium (He) on the sliding and mechanical properties of a vanadium (V) E5(310)/[001] grain boundary (GB) have been investigated using a first-principles method. It has been found that He was energetically favorable sitting at the GB region with a segregation energy of -0.27 eV, which was attributed to the special atomic configurations and charge density distributions of the GB. The maximal sliding energy barrier of the He-doped GB was calculated to be 1.73 J/m^2, 35% larger than that of the clean GB. This suggested that the presence of He would hinder the V GB mobility. Based on the thermodynamic criterion, the total energy calculations indicated that the embrittlement of V GB would be enhanced by He segregation. 相似文献
94.
GUO Yi-Qing ZHANG Xue-Yao ZHANG Jian-Li HU Hong-Bo ZHA Min HE Hui-Hai FENG Zhao-Yang WU Chao-Yong WANG Bo ZHANG Yi A.Surdo LU Hong 《中国物理C(英文版)》2010,34(5)
'G4argo', a GEANT4-based simulation package for the ARGO-YBJ detector, is described in this paper. G4argo incorporates in the simulation the true RPC time resolution and another 0.5 ns time uncertainty which is introduced from the offline calibration of TDC. In addition, the correct RPC geometry and the true materials for the ARGO-YBJ experimental hall are implemented. As a result, G4argo simulation shows a very good agreement with real data. 相似文献
95.
The design and fabrication of graded-refractive-index (GRIN) antireflection (AR) coatings with wide-angle and broadband characteristics are demonstrated. The optimization of the graded-index profiles with a genetic algorithm is used in the design of the GRIN AR coatings. The average reflectance over a wavelength range from 400 nm to 800 nm and angles of incidence from 0° to 80° could be reduced to only 0.1% by applying an optimized AR coating onto BK7 glass. The optimization of step-graded GRIN AR coating is then further investigated in detail. A two-layer AR coating was deposited by electron beam evaporation with glancing angle deposition technology, and the positional homogeneity was improved by depositing the film from two opposite directions. The microstructure of the AR coating was investigated by scanning electron microscopy, and the residual reflectances of the coating sample are in agreement with theoretical calculations. The optimized GRIN AR coatings are beneficial to increasing the efficiency of light utilization. 相似文献
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97.
Molecular dynamics simulations along with scanning tunneling microscopy (STM) imaging demonstrate the formation of a novel type of nanorods, with a stable [permethrin(beta-CD)(2)](n) structure in which the host:guest ratio is 2:1 and n=21-27 giving a length of approximately 30.0-38.5 nm and an average diameter of approximately 1.5 nm, self-assembled from an inclusion complex composed of permethrin and biocompatible beta-cyclodextrin. 相似文献
98.
Hong-Bo Ni 《Journal of fluorine chemistry》2006,127(3):426-432
The radical reactions of polyolefin and olefin copolymers (4-9), polydienes and diene coplymers (10-15), and polysiloxane (16) with “magic blue” reagent containing H-abstracting agent-bis{perfluoro-1-[1-(2-fluorosulfonyl)ethoxy]ethyl}nitroxide [FSO2CF2CF2OCF(CF3)]2N(O) (2)and spin trap-perfluoro-1-nitroso-[1-(2-fluoro-sulfonyl)ethoxy]ethane FSO2CF2CF2OCF(CF3)NO (3) were studied by EPR detection of the spin adducts of the corresponding polymeric radicals generated in the H-abstraction step to the spin trap 3, namely, the nitroxides FSO2CF2CF2OCF(CF3)N(O) (polymer-H) 17-29. EPR studies have provided information about the regio-selectivity of H-abstraction, the subsequent radical steps followed H-abstraction and grounded a possibility of employing “magic blue” reagent in polymer modification via H-abstraction-initiated grafting polymerization. 相似文献
99.
Li Dong-Hui Xu Jie-Feng Guan Hong-Bo 《Journal of Optimization Theory and Applications》2021,190(2):628-649
Journal of Optimization Theory and Applications - We are concerned with the tensor equations whose coefficient tensors are M-tensors. We first propose a Newton method for solving the equation with... 相似文献
100.