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21.
Youming Zou Hongjuan Zhang Zheng Chen Jianwen Wang Yun Li 《Applied Surface Science》2007,253(9):4356-4360
The excess weight loss due to the evaporation of zinc compound is observed in the growth of ZnO film by trifluoroacetate metalorganic deposition (TFA-MOD) method. Higher temperature (>90 °C) aging and/or addition of monoethanolamine (MEA) are effective to prevent the evaporation of zinc compound and increase the yield of ZnO. The mechanism of preventing evaporation is that zinc trifluoroacetate is hydrolyzed into Zn4O(CF3COO)6. A three-dimensional structure of Zn4O(CF3COO)6 is proposed. It is shown that higher temperature aging does harm to the surface morphology of ZnO films. The addition of MEA reduces the required aging temperature thus improves the surface morphology. 相似文献
22.
Gumberidze A Stöhlker T Banaś D Beckert K Beller P Beyer HF Bosch F Cai X Hagmann S Kozhuharov C Liesen D Nolden F Ma X Mokler PH Orsić-Muthig A Steck M Sierpowski D Tashenov S Warczak A Zou Y 《Physical review letters》2004,92(20):203004
Radiative recombination transitions into the ground state of cooled bare and hydrogenlike uranium ions were measured at the storage ring ESR. By comparing the corresponding x-ray centroid energies, this technique allows for a direct measurement of the electron-electron contribution to the ionization potential in the heaviest He-like ions. For the two-electron contribution to the ionization potential of He-like uranium we obtain a value of 2248+/-9 eV. This represents the most accurate determination of two-electron effects in the domain of high-Z He-like ions, and the accuracy reaches already the size of the specific two-electron radiative QED corrections. 相似文献
23.
Zhongzhi Zhang Shuigeng Zhou Zhan Su Tao Zou Jihong Guan 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(1):141-147
In this paper, we define a stochastic Sierpinski gasket, on the basis of which we construct a network called random Sierpinski
network (RSN). We investigate analytically or numerically the statistical characteristics of RSN. The obtained results reveal
that the properties of RSN is particularly rich, it is simultaneously scale-free, small-world, uncorrelated, modular, and
maximal planar. All obtained analytical predictions are successfully contrasted with extensive numerical simulations. Our
network representation method could be applied to study the complexity of some real systems in biological and information
fields. 相似文献
24.
建立反相高效液相色谱-光电二极管联用法同时测定了荆芥中乌索酸和齐墩果酸的含量。色谱柱为Kromasil C18柱(250mm×4.6mm,5μm),流动相为甲醇-水(86∶14),流速0.8mL.min-1,光电二极管阵列检测器(PAD),检测波长210nm,柱温25℃。在选定色谱条件下线性范围良好,乌索酸和齐墩果酸的样品加样回收率分别为98.6%和99.2%,RSD为1.1%和1.9%。方法简便,分离效果好,可用于荆芥中乌索酸和齐墩果酸含量的测定。 相似文献
25.
正The Chang'E-3(CE-3)mission began with a smooth countdown and flawless launch on the Long March 3B rocket from the Xichang satellite launch center at 01:30 CST on December 2,2013.It landed on the northeastern Imbrium basin(340.49°E,44.12°N)at 21:11 CST on December 14,2013,and the Yutu rover was deployed from the lander the next morning at 04:35.The lander was equipped with a number of remote-sensing 相似文献
26.
B.S. Zou G.X. Peng R.G. Ping H.C. Chiang W.X. Ma P.N. Shen 《The European Physical Journal A - Hadrons and Nuclei》2001,11(3):341-344
For J/Ψ↦
pπ0 and
pπ+π-, the π0
p and pπ+π- systems are limited to be pure isospin-(1/2) due to isospin conservation. This is a big advantage in studying N* resonances from J/Ψ decays, compared with πN and γN experiments. The process J/Ψ↦
N
* or p
provides a new way to probe the internal structure of the N* resonances. Here we report a quark model calculation for J/Ψ↦
p,
N
*(1440) and
N
*. The implication for the internal structure of N
*(1440) is discussed.
Received: 1 June 2001 / Accepted: 20 June 2001 相似文献
27.
Xiaoteng Li Dongqing Zou Bin Cui Yuan Li Mei Wang Dongmei Li Desheng Liu 《Physics letters. A》2018,382(35):2475-2483
By first-principles calculations, we propose three heterojunction nanodevices based on zigzag silicene nanoribbons with different edge-hydrogenated topological line defects. The devices all present excellent spin-filtering properties with 100% spin polarization as well as remarkable rectifying effect (with rectification ratio around 102) and negative differential resistance behaviors. Our findings shed new light on the design of silicon-based nanodevices with intriguing spintronic applications. 相似文献
28.
All-reflective optical systems,due to their material absorption and low refractive index,are used to create the most suitable devices in extreme ultraviolet lithography (EUVL).In this letter,we present a design for an all-reflective lithographic projection lens.We also discuss its design idea and structural system.After analysis of the four-mirror optical system,the initial structural parameters are determined,the optical system is optimized,and the tolerances of the system are analyzed.We also show the implementation of optimal layout and desired imaging performance. 相似文献
29.
30.
In this topic, a new approach to the analysis of time-variation dynamics is proposed by use of Legendre series expansion and Legendre integral operator matrix. The theoretical basis for effective solution of time-variation dynamics is therefore established, which is beneficial to further research of time-variation science. Supported by Shanghai Key Project Research Foundation. 相似文献