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41.
In this paper,we research general Defective Cion Problem under the model S,i.e,the number d of Defective cions is not fixed. For d=O,1,or 2. we get some good results. 相似文献
42.
MPT-X是带4个内导体坏的托卡马克装置。本文用差分法计算了MPT-X磁偏滤器的平衡磁面位形。结果表明,迭加上各种强度的八极场都能形成磁偏滤器位形,形成电流的放电中心区域随八极场的增加而收缩。还模拟了从多极器运行模式向托卡马克的过渡。 相似文献
43.
王定江 《数学的实践与认识》2003,33(2):86-90
本文建立了森林发展系统的一类非线性林龄面积结构的半离散模型 ,并讨论了半离散系统解的存在唯一性 ,给出了线性半离散系统稳定的一些充分条件 相似文献
44.
Li S Wang D Wang K Akamatsu T Ma Z Han J 《The Journal of the Acoustical Society of America》2007,121(6):3938-3946
Acoustic signals from wild Neophocaena phocaenoides sunameri were recorded in the waters off Liao-dong-wan Bay located in Bohai Sea, China. Signal analysis shows that N. p. sunameri produced "typical" phocoenid clicks. The peak frequencies f(p) of clicks ranged from 113 to 131 kHz with an average of 121+/-3.78 kHz (n=71). The 3 dB bandwidths delta f ranged from 10.9 to 25.0 kHz with an average of 17.5+/-3.30 kHz. The signal durations delta t ranged from 56 to 109 micros with an average 80+/-11.49 micros. The number of cycles N(c) ranged from 7 to 13 with an average of 9+/-1.48. With increasing peak frequency there was a faint tendency of decrease in bandwidth, which implies a nonconstant value of f(p)/delta f. On occasion there were some click trains with faint click energy presenting below 70 kHz, however, it was possibly introduced by interference effect from multiple pulses structures. The acoustic parameters of the clicks were compared between the investigated population and a riverine population of finless porpoise. 相似文献
45.
46.
一种新的三维计算全息图的计算方法 总被引:1,自引:0,他引:1
介绍了一种制作真实三维物体计算全息图的新方法。用摄像机记录三维物体在非相干光照明条件下两个正交方向上不同视角的一系列投影像,将这些投影像导入计算机,在MATLAB中对其作快速傅里叶变换。对这一系列二维投影像的傅里叶变换图进行抽样,得到三维物体在透镜后焦平面上的光场分布,进而制成一张计算全息图。结果证明该方法可以实现对真实物体三维全息图的合成,并且在算法实现上更加简单,提高了程序的运行速度,有利于改善全息图再现像的质量。为解决真实物体相干全息记录中光源功率和相干长度对全息记录可行性的限制指出了一个新的方向。 相似文献
47.
In this letter, we investigate the influence of the stress on magnetoelectric (ME) effect in a magnetostrictive-PZT bilayer.
ME voltage coefficient α*E = δE / δH, where δE is the induced electric field for an applied alternating current (ac) magnetic field δH, is obtained by solving the stress-related piezoelectric constitutive equation and the conventional magnetostrictive equation
with appropriate boundary condition. Based on the free-energy density function of the PZT film in stress state, we get the
stress-related piezoelectric charge coefficient p
d*31 and dielectric permittivity pε*33. After taking the cobalt ferrite (CFO) as magnetostrictive phase, it is found that α*E increases with decreasing 2-d compressive stress for CFO-PZT, which not only is qualitatively consistent with previous experimental
measurements, but also provides a possible route to improve the ME effect.
相似文献
48.
Improving nucleation in the fabrication of high-quality 3D macro-porous copper film through the surface-modification of a polystyrene colloid-assembled template 下载免费PDF全文
A new approach is developed to the fabrication of high-quality
three-dimensional macro-porous copper films. A highly-ordered
macroporous copper film is successfully produced on a
polystyrene sphere (PS) template that has been modified by
sodium dodecyl sulfate (SDS). It is shown that this procedure
can change a hydrophobic surface of PS template into a
hydrophilic surface. The present study is devoted to the
influence of the electrolyte solution transport on the
nucleation process. It is demonstrated that the permeability of
the electrolyte solution in the nanochannels of the PS template
plays an important role in the chemical electrodeposition of
high-quality macroporous copper film. The permeability is
drastically enhanced in our experiment through the surface
modification of the PS templates. The method could be used to
homogeneously produce a large number of nucleations on a
substrate, which is a key factor for the fabrication of the
high-quality macroporous copper film. 相似文献
49.
S.-J. Ding V. Zaporojtchenko J. Kruse J. Zekonyte F. Faupel 《Applied Physics A: Materials Science & Processing》2003,76(5):851-856
The interfacial bonding and mixing between evaporated aluminum and a vapor deposited Teflon AF (abbreviated to AF) film have
been investigated with X-ray photoelectron spectroscopy. Graphite carbon (C–C), and aluminum carbide (Al–C), oxide (Al–O–C)
and fluoride (Al–F) are formed when aluminum atoms are deposited on to the AF film. With increasing deposition of aluminum,
the concentrations of these newly formed components increase gradually. Moreover, in situ annealing results in remarkable
increases in the C–C, Al–C, Al–O–C and Al–F configurations and a decrease in metallic aluminum. No significant diffusion of
aluminum into the AF film was observed during the annealing. The Al compounds form a layer at the Al/AF interface that acts
as an adhesion promoter and diffusion barrier.
Received: 21 October 2002 / Accepted: 22 October 2002 / Published online: 15 January 2003
RID="*"
ID="*"Corresponding author. Fax: +49-431/880-6229, E-mail: sjding@yahoo.com 相似文献
50.
FePt films were deposited on Cr1-xMox underlayers by dc magnetron sputtering. The effects of the Mo content in the underlayers, underlayer thickness, substrate temperature, and FePt film thickness on the structural and magnetic properties of the FePt films were studied. Experimental results showed that the (200) textured Cr90Mo10 film was a promising underlayer for promoting the growth of the L10 FePt films with (001) preferred orientation at relatively low temperatures. With the Cr90Mo10 underlayers, the ordering process of the FePt films could start at 200 °C. Both the ordering degree and the out-of-plane coercivity (Hc) of the FePt films increased with an increase in substrate temperature. When the substrate temperature was ≥250 °C, the FePt films grown on the Cr90Mo10 underlayers could have the (001) preferred orientation. The FePt films grown on the Cr90Mo10 underlayers at different temperatures showed a continuous microstructure. The out-of-plane coercivities Hc decreased while the ordering degree increased with increased FePt film thickness, which could be due to the variation of the magnetic reversal mechanism from rotation predominant mode to domain wall motion predominant mode. PACS 68.55.Jk; 75.50.Ss 相似文献