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91.
采用直流驱动等离子体激励器并通过气流场的碘线表征法研究了边界表面放电等离子体对低气压超音速氦气流场的作用。实验结果表明,边界表面放电等离子体的阴极区对以超音速流动的氦气的控制作用在符合实际工程条件的低气压下是有效果的;等离子体激励器的驱动电压越高,气流场的流动控制效果越好;定性观察表明激励器的阴极板的面积越大,实际作用区域越大,相应的实际控制效果越好。 相似文献
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94.
Naveed Ahmad Khan Fahad Sameer Alshammari Carlos Andrs Tavera Romero Muhammad Sulaiman 《Entropy (Basel, Switzerland)》2021,23(12)
In this paper, we have analyzed the mathematical model of various nonlinear oscillators arising in different fields of engineering. Further, approximate solutions for different variations in oscillators are studied by using feedforward neural networks (NNs) based on the backpropagated Levenberg–Marquardt algorithm (BLMA). A data set for different problem scenarios for the supervised learning of BLMA has been generated by the Runge–Kutta method of order 4 (RK-4) with the “NDSolve” package in Mathematica. The worth of the approximate solution by NN-BLMA is attained by employing the processing of testing, training, and validation of the reference data set. For each model, convergence analysis, error histograms, regression analysis, and curve fitting are considered to study the robustness and accuracy of the design scheme. 相似文献
95.
超细钼丝是Z-pinch物理实验常用的材料之一。采用亚硫酸脉冲镀金技术,在超细钼丝上镀制一层均匀致密的金层来改善钼丝性能。实验研究和优化了影响镀层质量和沉积效率的主要工艺条件,优化后的阴极电流密度2 mA/cm2,溶液pH值8.5,溶液温度40°。用扫描电镜观察镀金钼丝的表面形貌及镀层质量;用划痕法测试了镀层与钼丝表面的结合力。实验结果表明,采用经过优化的镀金工艺能够在直径小于15 μm的钼丝上镀制厚度0.6~2.5 μm的致密金层,且能够有效地降低钼丝表面的粗糙度和提高抗氧化能力,满足Z-pinch实验的需要。 相似文献
96.
Electrical explosion of wires (EEW) is a promising method for nanopowders preparation and insensitive explosives ignition. Plasma radiation plays a key role in the ignition process while little attention has been paid on this phenomenon before. This letter introduces optical emission behaviors of electrical explosions for nine materials in air, Helium, and Argon with the SWE-2 platform. Experimental results indicated that the light intensity for non-refractory metals decayed rapidly after the discharge ended. In contrast, for refractory metals, the emission continued to increase and lasted for a long period after the discharge ceased. As for spectra, the emission consisted of line and continuous spectra. With the atomic number increased, the density of lines grew rapidly, leading to a “continuous” appearance. 相似文献
97.
提出了一种基于金线填充的双芯光子晶体光纤超短偏振分束器,并进行了有限元分析.金线表面激发的表面等离子激元与双芯光子晶体光纤纤芯模之间的强烈耦合,导致更短的偏振分束器长度和更大的工作带宽.与同类的偏振分束器相比,所提出的偏振分柬器能同时实现较短的长度和较高的消光比.数值结果表明,长度为0.263 mm的偏振分束器,在波长1.55 μm处消光比达-70 dB,-20 dB消光比带宽为124 nm. 相似文献
98.
Paolo Tripodi Nicolas Armanet Alessandro Avveduto Jenny Darja Vinko 《Physics letters. A》2009,373(35):3101-3108
A series of hydrogenation/dehydrogenation cycles have been performed on palladium wire samples, stressed by a constant mechanical tension, in order to investigate the changes in electrical and mechanical properties. A large increase of palladium electrical resistivity has been reported due to the combined effects of the production of defects linked to hydrogen insertion into the host lattice and the stress applied to the sample. An increase of the palladium sample strain due to hydrogenation/dehydrogenation cycles in α→β→α phase transitions is observed compared to the sample subjected to mechanical tension only. The loss of initial metallurgical properties of the sample occurs already after the first hydrogen cycle, i.e. a displacement from the initial metallic behavior (increase of the resistivity and decrease of thermal coefficient of resistivity) to a worse one occurs already after the first hydrogen cycle. A linear correlation between palladium resistivity and strain, according to Matthiessen's rule, has been found. 相似文献
99.
DAI Zhi-Yong XIE Yu-Tong LI Hong ZHANG Wen-Wei LIU Yun-Long PAN Hai-Feng ZHANG Lin-Wen DENG Jian-Jun 《中国物理C(英文版)》2009,33(9)
DRAGON-Ⅰ designed and manufactured by CAEP is a linear induction accelerator which can produce a 20 MeV-3 kA-60 us electron beam. The high performance required for the machine is determined by the beam quality and thus is greatly dependent on the accelerator alignment. In order to reduce the chromatic effect of the beam, the stretched wire technique has been developed to measure magnetic axes of the cells precisely, and the dipole steering magnets have been equipped into each cell to correct its magnetic axis misalignment. Finally, the laser tracker has been used to examine the installation error of the accelerator. In this paper, different alignment techniques and the primary results are presented and discussed. 相似文献
100.
用滑线式电桥巧测微安表的内阻 总被引:1,自引:0,他引:1
本文从讨论滑线式电桥的构成原理出发,全面分析了滑线式电桥测量的最有利条件及阻值的可信度。在此基础上详细研究了运用滑线式电桥测量微安表内阻的具体操作方法。 相似文献