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101.
102.
Traditional photoelectric devices can generate only DC electric signals under constant illumination. In this work, a novel photoelectric metal-oxide-semiconductor field-effect transistor (MOSFET) with AC output under constant illumination is introduced, in which the channel current is modulated by the gate voltage. This virtue can greatly simplify the signal processing circuitry. This photoelectric MOSFET has been successfully fabricated using a standard 0.8 micron MOSFET process. 相似文献
103.
Jianwen Huang Yaoyao Li Yadong Zhang Gaofeng Rao Chunyang Wu Yin Hu Xianfu Wang Ruifeng Lu Yanrong Li Jie Xiong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17619-17625
The oxygen evolution reaction (OER) has been explored extensively for reliable hydrogen supply to boost the energy conversion efficiency. The superior OER performance of newly developed non‐noble metal electrocatalysts has concealed the identification of the real active species of the catalysts. Now, the critical active phase in nickel‐based materials (represented by NiNPS) was directly identified by observing the dynamic surface reconstruction during the harsh OER process via combining in situ Raman tracking and ex situ microscopy and spectroscopy analyses. The irreversible phase transformation from NiNPS to α‐Ni(OH)2 and reversible phase transition between α‐Ni(OH)2 and γ‐NiOOH prior to OER demonstrate γ‐NiOOH as the key active species for OER. The hybrid catalyst exhibits 48‐fold enhanced catalytic current at 300 mV and remarkably reduced Tafel slope to 46 mV dec?1, indicating the greatly accelerated catalytic kinetics after surface evolution. 相似文献
104.
采用国产喷雾热分解设备制备了Bi-2223 前驱粉末, 分别选用一步收集和分级收集热分解后的粉末, 对不同方式收集的粉末进行了XRD 分析、SEM 观察以及ICP-AES 分析, 对比了粉末在相成份以及含量、 外观形貌、 粒径大小和元素原子配比等方面的差别, 最终发现采用一步收集方式采集的粉末在相组成、 成分均匀度以及原子配比方面均优于分级收集粉末, 一步收集方式更适合于收集Bi-2223 喷雾热分解粉末. 相似文献
105.
Rui Wang Bo Yuan Gaofeng Wang Fan Yi 《International Journal of Infrared and Millimeter Waves》2007,28(8):639-649
An efficient approach for designing directive patch antennas using metamaterials is presented. Based on the left-handed-material
(LHM) transmission line model, circuit elements L and C of the LHM equivalent circuit model are computed in terms of the prescribed
desirable characteristics of directive patch antennas. Formulae to calculate the LHM design parameters from the circuit elements
L and C are developed. Design examples for the GSM900 and GSM1800 frequency bands in mobile communications are performed to
illustrate validation and efficiency of this design approach. 相似文献
106.
Shaoqiu Xiao Bing-Zhong Wang Gaofeng Wang 《International Journal of Infrared and Millimeter Waves》2002,23(7):1091-1099
Reconfigurable antenna is a novel concept of antenna. A novel reconfigurable millimeter-wave patch antenna is proposed and simulated by the finite-difference time-domain (FDTD) method. The simulation results demonstrate that the antenna can operate in two states and shift the operation frequency band between 22.830.8GHz and 28.737.3GHz as the state is changed. This antenna is useful for millimeter-wave wireless communication and radar systems. 相似文献
107.
边界元法中的周期旋转对称 总被引:1,自引:0,他引:1
本文证明具有周期旋转对称性的结构,在对称适应的座标架下,其边界元方程的系数矩阵具有块循环的形式,给出分块的系列子问题求解方法,适于任意形式的载荷分布。 相似文献
108.
Bing-Zhong Wang Guanqiang Zhang Gaofeng Wang 《International Journal of Infrared and Millimeter Waves》1996,17(8):1431-1439
Microstrips terminated with resistive loads in enclosures with slot apertures are studied by the FDTD method. The FDTD simulation shows that the EMI signal levels induced in the microstrip circuits are strongly affected by the orientation of the circuit related to the direction of the slot.This work was supported by the National Natural Science Fund of China, and by the Fok Ying Tung Education Foundation. 相似文献
109.
Feiyun Li Gaofeng Shi Guoying Wang Taichun Guo Xinming Lei 《Research on Chemical Intermediates》2016,42(8):6757-6767
We synthesized 5-hydroxymethylfurfural (HMF) from carbohydrates using metal chloride catalysts. A 33.2 % yield of HMF was obtained from raw Dioscorea composita biomass with high starch by using a catalyst system composed of CrCl3·6H2O and LaCl3·6H2O at 120 °C for 4 h in N,N-dimethylacetamide containing lithium chloride. The catalyst system is also cost-effective for the conversion of soluble starch into HMF. In addition, levulinic acid was not formed in the reactions. 相似文献
110.
Peng Zhongdong Wang Gaofeng Cao Yanbing Zhang Zhijian Du Ke Hu Guorong 《Journal of Solid State Electrochemistry》2016,20(10):2865-2871
Journal of Solid State Electrochemistry - Li2MnO3 coated spinel lithium manganese oxide (LiMn2O4) materials have been successfully synthesized by a sol-gel method. Scanning electron microscopy... 相似文献