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221.
Based on Ginzburg-Landau theory, we study the temperature dependence of upper critical field and London penetration depth for the superconducting crystal Lu2Fe3Si5. All the results fit the experimental data well. We also indicate that the larger gap opens in the quasi-one-dimensional part of Fermi surfaces. 相似文献
222.
Hai Wang Yong Liu Minyi Zhong Hongmei Xu Hong Huang Hui Shen 《Journal of nanoparticle research》2011,13(5):1855-1863
Various TiO2 nanomaterials, such as nanosheets, nanoflowers, and nanowires were directly self assembled on titanium substrate on a large
scale under hydrothermal conditions. The morphology of the formed TiO2 nanomaterials could be easily tuned by varying the experimental parameters of temperature, reaction time, and the NaOH concentration.
A possible formation mechanism was suggested on the basis of the shape evolution of TiO2 nanostructures by SEM images in combination with XRD patterns of as-grown samples. The optical properties of TiO2 nanosheets, nanoflowers, and nanowires were characterized by reflectance spectroscopy. The studies revealed that the absorption
capability of visible light is obviously different for TiO2 with different morphologies. Moreover, TiO2 nanosheets exhibited better light trapping than TiO2 nanoflowers and TiO2 nanowires due to their unique nanostructure. 相似文献
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Observation of Diffusion Process of a Water Droplet Immersed in Protein Solution in Microgravity 下载免费PDF全文
Pure liquid-liquid diffusion driven by concentration gradients is hard to study in a normal gravity environment since convection and sedimentation also contribute to the mass transfer process. We employ a Math Zehnder interferometer to monitor the mass transfer process of a water droplet in EAFP protein solution under micro- gravity condition provided by the Satellite Shi Jian No 8, A series of the evolution charts of mass distribution during the diffusion process of the liquid droplet are presented and the relevant diffusion coefficient is determined. 相似文献
225.
Numerical Simulation of Shear-Horizontal-Wave-Induced Electromagnetic Field in Borehole Surrounded by Porous Formation 下载免费PDF全文
Seismoelectric fieM excited by purely torsional loading applied directly to the borehole wall is considered. A brief formulation and some computed waveforms show the advantage of using shear-horizontal (SH) transverseelectric (TE) seismoelectric waves logging to measure shear velocity in a fluid-saturated porous formation. By assuming that the acoustic field is not influenced by its induced electromagnetic field due to seismoeleetric effect, the coupling governing equations for electromagnetic field are reduced to Maxwell equations with a propagation current source. It is shown that this simplification is valid and the borehole seismoelectric conversion efficient is mainly dependent on the electrokinetic coupling coefficient. The receivers to detect the conversion electromagnetic field and to obtain shear velocity can be set in the borehole fluid in the SH-TE seismoelectric wave log. 相似文献
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连续激光辐照锗材料损伤的数值模拟研究 总被引:2,自引:0,他引:2
以热传导理论和热弹应力理论为基础,建立了连续平顶激光辐照锗材料的二维非稳态物理模型。对受辐照锗材料的热-力场分布进行数值模拟,比较了激光辐照时间对靶材热-力场分布的影响,探讨了温度场及应力场空间梯度随半径的分布以及激光辐照时间对热-力场空间梯度的影响。计算结果表明,靶材中心温升效应最大,而应力最大值出现在光斑半径外侧;光斑边缘处温度场和应力场梯度绝对值均达到最大,随着辐照时间的延长,材料同一点温度场和应力场梯度均增大。在给定条件下,计算了靶材的损伤时间,应力损伤域值最先达到。 相似文献
230.
Many dark energy models fail to pass the cosmic age test because of the old quasar APM 08279+5255 at redshift z=3.91,the ΛCDMmodel and holographic dark energy models being no exception.Inthis paper,we focus onthe topic of the age problem inthe new agegraphic dark energy(NADE)model.We determine the age of the universe in the NADE model by fitting the observational data,including type Ia supernovae(SNIa),baryon acoustic oscillations(BAO)and the cosmic microwave background(CMB).We find that the NADE model also... 相似文献