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集成模块化Cantor网络的控制和光学实现 总被引:4,自引:3,他引:1
提出光学集成模块化Cantor网络,并建立了Cantor网络的快速控制体系,该网络是基于极化多通道技术,利用晶体的双折射效应和电光特性实现网络的互连变换,该网络易安装,抗干扰。 相似文献
23.
Hui Sun Jie Feng Jiajun Wang Bin Yu Jing Sheng 《Journal of Macromolecular Science: Physics》2013,52(2):328-337
Isotactic polypropylene/poly(cis-butadiene) rubber (iPP/PcBR vol%: 80/20) blends were prepared by melt mixing with various mixing rotation speeds. The effect of mixing technique on microstructure and impact property of blends was studied. Phase structure of the blends was analyzed by scanning electron microscopy (SEM). All of the blends had a heterogeneous morphology. The spherical particles attributed to the PcBR-rich phase were uniformly dispersed in the continuous iPP matrix. With increase of the mixing rotation speed, the dispersed phase particle's diameter distribution became broader and the average diameter of the separated particles increased. The spherulitic morphology of the blends was observed by small angle light scattering (SALS). Higher mixing rotation speed led to a more imperfect spherulitic morphology and smaller spherulites. Crystalline structure of the blends was measured by wide angle X-ray diffraction (WAXD) and small angle X-ray scattering (SAXS). The introduction of 20 vol% PcBR induced the formation of iPPβ crystals. Higher rotation speed led to a decrease in microcrystal dimensions. However, the addition of PcBR and the increase of mixing rotation speed did not affect the interplanar distance. The long period values were the same within experimental error as PcBR was added or the mixing rotation speed quickened. The normalized relative degree of crystallinity of the blends slightly increased under lower rotation speeds (30 and 45 rpm) and decreased under higher rotation speeds. The notched Izod impact strength of the blends was enhanced as a result of the increase of mixing rotation speed. 相似文献
24.
Defect passivation is an important strategy to achieve perovskite solar cells(PVSCs) with enhanced power conversion efficiencies(PCEs) and improved stability because the trap states induced by defects in the interfaces and grain boundaries of perovskites are harmful to both large open circuit voltage and high photocurrent of devices. Here, zinc cations(Zn~(2+)) were used as a dopant to passivate defects of the CsPbI_2Br perovskite leading to Zn~(2+)-doped CsPbI_2Br film with fewer trap states, improved charge transportation, and enhanced light-harvesting ability. Thus, the best-performance PVSC based on CsPbI2 Br with the optimal Zn~(2+)doping shows a higher PCE of 12.16% with a larger open-circuit voltage(V_(OC)) of 1.236 V, an improved shortcircuit current(J_(SC)) of 15.61 mA cm~(-2) in comparison with the control device based on the pure CsPbI_2Br which exhibits a PCE of 10.21% with a V_(OC)of 1.123 V, a J_(SC)of 13.27 mA cm~(-2). Time-resolved photoluminescence results show that the Zn~(2+)doping leads to perovskite film with extended photoluminescence lifetime which means a longer diffusion length and subsequently enhanced photocurrent and open circuit voltage. This work provides a simple strategy to boost the performance of PVSCs through Zn~(2+)doping. 相似文献
25.
Chuan Lai Xiaogang Guo Mingfeng Wang Jiajun He Zhuli Wang Bin Xie 《Phosphorus, sulfur, and silicon and the related elements》2020,195(8):651-659
AbstractThis work presents on improvement in gravimetric measurement for determining the porosity and thickness of microporous silicon. Herein, the corrosion of fresh macroporous silicon (f-MPSi) in 1.0?M NaOH with different concentrations of polyethylene glycol (PEG 200/400/600) was studied by weight loss measurement and scanning electron microscopy (SEM). The results showed that the corrosion rate decreased with increasing polyethylene glycol concentration, and increased with an increase in temperature. Polyethylene glycol can inhibit the corrosion of f-MPSi in NaOH solution. Moreover, 1.0?M NaOH/PEG 600 (10%) can be used as the optimized solution to remove f-MPSi for measuring its porosity and thickness by gravimetric measurement. 相似文献
26.
Mengmeng Zhang Dr. Jiajun Wang Hui Xue Dr. Jinfeng Zhang Prof. Dr. Shengjie Peng Dr. Xiaopeng Han Prof. Dr. Yida Deng Prof. Dr. Wenbin Hu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18621-18625
Cu2O is a typical photoelectrocatalyst for sustainable hydrogen production, while the fast charge recombination hinders its further development. Herein, Ni2+ cations have been doped into a Cu2O lattice (named as Ni-Cu2O) by a simple hydrothermal method and act as electron traps. Theoretical results predict that the Ni dopants produce an acceptor impurity level and lower the energy barrier of hydrogen evolution. Photoelectrochemical (PEC) measurements demonstrate that Ni-Cu2O exhibits a photocurrent density of 0.83 mA cm−2, which is 1.34 times higher than that of Cu2O. And the photostability has been enhanced by 7.81 times. Moreover, characterizations confirm the enhanced light-harvesting, facilitated charge separation and transfer, prolonged charge lifetime, and increased carrier concentration of Ni-Cu2O. This work provides deep insight into how acceptor-doping modifies the electronic structure and optimizes the PEC process. 相似文献
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28.
Bao Changyuan He Qingqing Han Jiajun Cheng Jinning Zhang Ruitao 《Journal of Solid State Electrochemistry》2018,22(9):2917-2928
Journal of Solid State Electrochemistry - A polyaniline/sulfonated graphene (PANI/SG) nanostructure was synthesized as electrode material for an asymmetric supercapacitor via a novel in situ... 相似文献
29.
A sensitive electrochemiluminescence (ECL) biosensor for the specific DNA sequence of hepatitis C virus (HCV) was developed based on the efficient quenching effect of the ferrocene cluster functionalized gold nanoparticles (Fc@AuNPs) on the ECL of electrodeposited silica@Ru(bpy)32+-chitosan-graphene oxide nanocomposite (SiO2@Ru−CS−GO). Graphene oxide (GO) can accelerate electron transfer rate, thus improving the ECL of Ru(bpy)32+ on electrode surface. The molecular beacons (MB) was fixed to SiO2@Ru−CS−GO by glutaraldehyde (GA) using the Schiff reaction between amino groups of chitosan (CS) and MB. The ECL of SiO2@Ru−CS−GO was depressed greatly by the Fc@AuNPs labelled at the end of MB, then, a stronger ECL was observed when the distance between Fc@AuNPs and SiO2@Ru−CS−GO increased after the hybridization of target DNA with MB. Under optimum conditions, the restored ECL intensity increased linearly with the target DNA concentration in the range of 1.0×10−16∼1.0×10−10 mol ⋅ L−1, and the limit of detection (LOD) is 1.4×10−17 mol ⋅ L−1. The proposed method exhibits acceptable stability and reproducibility. In general, the constructed HCV biosensor can be used for the sensitive detection of HCV in human serum, suggesting potential application prospects in bioanalysis. 相似文献
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