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961.
Ping He Huili Wang Lili Zhang Jialing Wang Changtao Mo Cheng Wang Xudong Li Deying Chen 《Optics & Laser Technology》2012,44(3):631-634
We reported a cavity-dumped operation of electro-optical Q-switched Nd:GdVO4 laser at high repetition rates for the first time. A constant 5.5 ns pulse duration was realized. The maximum average output power was 5.1 W at the highest repetition rate of 50 kHz, corresponding to a peak power of 18.5 kW. 相似文献
962.
To synthesize low-cost, highly conductive metal nanoparticles for inkjet printing materials, we synthesized Sn–Ag bimetallic
nanoparticles using a polyol process with poly(vinyl pyrrolidone). Because a surface oxidation layer forms on Sn nanoparticles,
various compositions of Sn–xAg [x = 0, 20, 40, 60, 80, 100 (wt%)] nanoparticles were synthesized and characterized for the purpose of removing the β-Sn phase.
The results of XPS, TEM, and XRD analyses confirm that the formation of a bimetallic phase, such as Ag4Sn or Ag3Sn, hinders the β-Sn phase and, consequently, leads to the removal of the surface oxidation layer. To measure the sheet resistance
of various compositions of Sn–Ag nanoparticles, we made the ink that contains Sn–Ag by dispersing 10 wt% of Sn–Ag nanoparticles
in methanol. The sheet resistance is decreased by the conductive Sn–Ag phases, such as the fcc, Ag4Sn, and Ag3Sn phases, but sharply increased by the low-conductive Sn nanoparticles and the surface oxidation layer on the Sn nanoparticles.
The sheet resistance results confirm that 80Ag20Sn and 60Ag40Sn bimetallic nanoparticles are suitable candidates for inkjet
printing materials. 相似文献
963.
Metal-induced crystallization method is one of the favorable non-laser crystallization methods for thin-film transistors in large-area displays. However, it is necessary to reduce metal contamination in the film to lower leakage current for the device applications. A new two-step crystallization method, consisting of a nucleation step by AlCl3 vapor-induced crystallization and a grain growth step by a pulsed rapid thermal annealing, has been proposed to increase the grain size and reduce the residual metal contamination in crystallized poly-Si films. The grain size of the poly-Si film crystallized by the VIC + PRTA two-step crystallization process was as large as 70 μm. Furthermore, the Al concentration in the poly-Si film was reduced by two orders of magnitude from 1 × 1020 cm?3 by VIC only process to 1.4 × 1018 cm?3 by the two-step process. As a result, the minimum leakage current of poly-Si TFTs using the poly-Si film prepared by the two-step process was reduced from 1.9 × 10?10 A/μm to 2.8 × 10?11 A/μm at a drain voltage of 5 V, without carrier mobility degradation. 相似文献
964.
Asymptotic solution of weak nonlinear model for mid-latitude stationary wind field of two-layer barotropic ocean
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The weak nonlinear model of two-layer barotropic ocean with Rayleigh dissipation is built. The analytic asymptotic solution is derived in mid-latitude stationary wind field, and the physical meaning of the corresponding problem is discussed. 相似文献
965.
Hierarchical and probabilistic quantum state sharing via a non-maximally entangled |χ〉 state
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A scheme that probabilistically realizes hierarchical quantum state sharing of an arbitrary unknown qubit state with a four-qubit non-maximally entangled |χ state is presented in this paper. In the scheme, the sender Alice distributes a quantum secret with a Bell-state measurement and publishes her measurement outcomes via a classical channel to three agents who are divided into two grades. One agent is in the upper grade, while the other two agents are in the lower grade. Then by introducing an ancillary qubit, the agent of the upper grade only needs the assistance of any one of the other two agents for probabilistically obtaining the secret, while an agent of the lower grade needs the help of both the other two agents by using a controlled-NOT operation and a proper positive operator-valued measurement instead of the usual projective measurement. In other words, the agents of two different grades have different authorities to reconstruct Alice’s secret in a probabilistic manner. The scheme can also be modified to implement the threshold-controlled teleportation. 相似文献
966.
二维平纹编织C/SiC复合材料的超高速碰撞实验 总被引:1,自引:0,他引:1
利用电炮加载聚酯薄膜飞片分别对二维平纹编织C/SiC复合材料(2D-C/SiC)和LY12硬铝材料
在3.4~9.5km/s速度下进行碰撞实验。利用光纤位移干涉仪测定了靶材的自由面速度,并对高速撞击碎片
颗粒进行了收集,采用超声波扫描系统无损检测等方法对2D-C/SiC材料在超高速冲击载荷作用下的力学响
应进行了检测。结果表明,随着冲击能量的增大,2D-C/SiC材料板自由面速度逐渐升高,损伤局部且面积逐
渐增大,碎片云团作用区域逐渐变大。与铝板相比,2D-C/SiC材料碎片云团整体能量较小、作用区域较大、能
量面密度较低,是飞行器防护结构设计中一种比较理想的防护材料。 相似文献
967.
以原子类型电拓扑状态指数(ETSI)有效表征了135 个多氯二苯并噻吩(PCDT)和135 个多氯二苯并噻吩砜(PCDTO2)的分子结构, 应用基于预测的变量选择与模型化(VSMP)方法建立PCDT 和PCDTO2 化合物在DB-5 气相色谱柱上的气相色谱保留指数(RI)与分子结构(ETSI)的定量相关模型, 模型的相关系数r2 分别为0.9939 和0.9729, LOO 交叉验证相关系数 q2 分别为0.9921 和0.9692. 为验证模型稳定性和预测能力, 应用17 个PCDT 和PCDTO2 训练集样本构建的QSRR 模型的r2 分别为0.9959 和0.9783, LOO 交叉验证相关系数 q2 分别为0.9921 和0.9740, 说明模型具有良好的稳定性. 以此模型预测外部8 个检验集及110 个预测集的RI 值, 8 个检验集样本的结果表明训练集模型具有良好预测能力. 相似文献
969.
Universality in the Two Matrix Model with a Monomial Quartic and a General Even Polynomial Potential
M. Y. Mo 《Communications in Mathematical Physics》2009,291(3):863-894
In this paper we studied the asymptotic eigenvalue statistics of the 2 matrix model with the probability measure
Z-1nexp(-n(tr(V(M1)+W(M2)-tM1M2)) dM1d M2,Z^{-1}_{n}{\rm exp}\left(-n\left({\rm tr}(V(M_1)+W(M_2)-\tau M_1M_2\right)\right) \, {\rm d}M_1{\rm d} M_2, 相似文献
970.
Contourlet变换应用于图像复原时容易引人伪吉布斯现象.非下采样Contourlet变换(NSCT)具有平移不变性,能够克服伪古布斯现象,但足由于基于学习的超分辨率复原需要建立不同分辨率的关系,而NSCT变换的结果是每一层图像大小都一样,不能像拉普拉斯金字塔那样建立高低分辨率图像的对应关系及运算量较大.针对这些问题,提出了基于改进的非下采样Contourlet变换(INSCT)的超分辨率复原算法.为了表示人脸特征,算法首先建立了INSCT金字塔.然后针对人脸的特殊性,在匹配过程中,采用对应点进行匹配的方法.实验表明该算法具有较好的性能,复原出的超分辨率人脸图像无论在主观视觉效果上还是在客观评价指标上都取得较好的结果,复原的图像具有更好的视觉效果,更逼真,更接近于原始高分辨率图像. 相似文献
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