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41.
本文通过对新疆农业生产函数的分析。讨论了生产要素转移情况。得出:1 新疆的土地资源已经过度使用;2 劳动力资源潜力很大,其转移方向正从流向第三产业转向第二产业;3 新疆农业资金缺乏,部分农业资金被非农业侵占。 相似文献
42.
Existing atomistic simulation techniques to study grain boundary motion are usually limited to either high velocities or temperatures and are difficult to compare to realistic experimental conditions. Here we introduce an adapted simulation method that can access boundary velocities in the experimental range and extract mobilities in the zero driving force limit at temperatures as low as ~0.2T(m) (T(m) is the melting point). The method reveals three mechanistic regimes of boundary mobility at zero net velocity depending on the system temperature. 相似文献
43.
Xiaoming Wu Yulin Hua Zhaoqi Wang Jiajin Zheng Shougen Yin Jiachun Deng Kongwu Wu Songliu Feijian Zhu Xia Niu 《Optik》2006,117(8):373-376
A bright white organic light-emitting diode (OLED) has been successfully fabricated in which a greenish-white emitting host Bis-(2-(2-hydroxyphenyl) benzothiazole)zinc (Zn(BTZ)2) is doped with an orange-red fluorescent dye 5,6,11,12-tetraphenylnaphthacene (rubrene). The pure white light emission with CIE coordinates of (0.341, 0.334) is achieved at the driving voltage of 20 V, and the corresponding luminance and external quantum efficiency are 4000 Cd/m2 and 0.63%. On the other hand, the pure red, green, and blue (RGB) emissions are obtained from the white OLED combined well with RGB custom-built optical color filters (CFs) with peaks at 616, 556, and 456 nm, respectively. Moreover, based upon the color mixture principles, we build a model of multi-color display mixed by the pure RGB emissions under the controllable bias. 相似文献
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Applications for piezoelectric efect have grown rapidly,and piezoelectric materials play important roles in countless areas of modern life.By means of twoscale method and coupled boundary layer,some new kinds of twoscale asymptotic expansions for solutions to the electrical potential and the displacement in quasi-periodic structure under coupled piezoelectric efect are derived,and the homogenization constants of piezoelectric materials are presented.The coupled twoscale relation between the electrical potential and the displacement is set up,and some improved asymptotic error estimates are analyzed. 相似文献
47.
Solitons and intrinsic localized modes in a one-dimensional antiferromagnetic chain 总被引:3,自引:0,他引:3 下载免费PDF全文
By use of the Hartree approximation and the method of multiple scales, we
investigate quantum solitons and intrinsic localized modes in a
one-dimensional antiferromagnetic chain. It is shown that there exist
solitons of two different quantum frequency bands: i.e., magnetic optical
solitons and acoustic solitons. At the boundary of the Brillouin zone, these
solitons become quantum intrinsic localized modes: their quantum
eigenfrequencies are below the bottom of the harmonic optical frequency band
and above the top of the harmonic acoustic frequency band. 相似文献
48.
We successfully fabricated a high-performance half-wave plate for the 405 nm wavelength based on monolithic integration of two nanograting layers. Each of the nanograting layers functions as a quarter-wave plate. Both of the nanograting layers were fully filled and planarized to achieve the monolithic integration. UV-nanoimprint lithography, along with thin-film deposition, high-aspect-ratio reactive ion etching, and trench-filling technologies, was used in fabrication and integration of the individual nanograting layers. High-aspect-ratio nanogratings with sub-50 nm linewidths and 100 nm spacing were fabricated to achieve good optical performance at the near-UV wavelength. The ability to integrate multiple nanostructure-based optical layers opens a path for integrated multifunction devices, as well as a new strategy for driving both miniaturization and cost. 相似文献
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维生素A酸在银溶胶液中的表面增强拉曼散射光谱 总被引:1,自引:2,他引:1
将水中不溶的药物维生素A酸(VAA)溶于氯仿中,然后与银溶胶液混合,振摇,取静置分层后的上层溶胶液测定表面增强拉曼光谱,氯仿在银溶胶中无表面增强效应,不干扰维生素A酸的测定。与固体粉末拉曼光谱相比较,对光谱峰归属进行了解释。通过分析CO伸缩振动带和ν(COO)振动峰明显增强的现象,讨论了维生素A酸分子在银颗粒表面可能的吸附取向,并推断维生素A酸在银表面的吸附发生在COO-基团。以维生素A酸表面增强拉曼光谱在1583cm-1处的峰强度对浓度进行线性回归,求得线性回归方程Y=10×108+95585,在10×10-6~50×10-5mol·L-1范围呈良好的线性关系,最小检测限为10×10-7mol·L-1。结果表明,维生素A酸表面增强拉曼光谱峰数量少,灵敏度高,是定量分析痕量维生素A酸的很好方法。 相似文献