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RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

《化学科学与工程前沿（英文）》 2023年第17卷第12期页码 2161-2161 doi: 10.1007/s11705-009-0143-3

摘要： RETRACTED ARTICLE: Momentum exchange coefficient for two jet flows mixing in a tee junction

关键词： tee junction Momentum exchange coefficient RETRACTED

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Developing a power monitoring and protection system for the junction boxes of an experimental seafloor

Jun WANG,De-jun LI,Can-jun YANG,Zhi-feng ZHANG,Bo JIN,Yan-hu CHEN

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1034-1045 doi: 10.1631/FITEE.1500099

摘要： A power monitoring and protection system based on an embedded processor was designed for the junction boxes (JBs) of an experimental seafloor observatory network in China. The system exhibits high reliability, fast response, and high real-time performance. A two-step power management method which uses metal-oxide-semiconductor field-effect transistors (MOSFETs) and a mechanical contactor in series was adopted to generate a reliable power switch, to limit surge currents and to facilitate automatic protection. Grounding fault diagnosis and environmental monitoring were conducted by designing a grounding fault detection circuit and by using selected sensors, respectively. The data collected from the JBs must be time-stamped for analysis and for correlation with other events and data. A highly precise system time, which is necessary for synchronizing the times within and across nodes, was generated through the IEEE 1588 (precision clock synchronization protocol for networked measurement and control systems) time synchronization method. In this method, time packets were exchanged between the grandmaster clock at the shore station and the slave clock module of the system. All the sections were verified individually in the laboratory prior to a sea trial. Finally, a subsystem for power monitoring and protection was integrated into the complete node system, installed in a frame, and deployed in the South China Sea. Results of the laboratory and sea trial experiments demonstrated that the developed system was effective, stable, reliable, and suitable for continuous deep-sea operation.

关键词： Power monitoring and protection Embedded processor Seafloor observatory network IEEE 1588 Junction boxes

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Numerical and experimental research of the characteristics of concentration solar cells

Zilong WANG, Hua ZHANG, Binlin DOU, Weidong WU, Guanhua ZHANG

《能源前沿（英文）》 2021年第15卷第2期页码 279-291 doi: 10.1007/s11708-019-0637-8

摘要： The development of automatic tracking solar concentrator photovoltaic systems is currently attracting growing interest. High concentration photovoltaic systems (HCPVs) combining triple-junction InGaP/lnGaAs/Ge solar cells with a concentrator provide high conversion efficiencies. The mathematical model for triple-junction solar cells, having a higher efficiency and superior temperature characteristics, was established based on the one-diode equivalent circuit cell model. A paraboloidal concentrator with a secondary optic system and a concentration ratio in the range of 100X–150X along with a sun tracking system was developed in this study. The GaInP/GalnAs/Ge triple-junction solar cell, produced by AZUR SPACE Solar Power, was also used in this study. The solar cells produced by Shanghai Solar Youth Energy (SY) and Shenzhen Yinshengsheng Technology Co. Ltd. (YXS) were used as comparison samples in a further comparative study at different concentration ratios (200X–1000X). A detailed analysis on the factors that influence the electrical output characteristics of the InGaP/lnGaAs/Ge solar cell was conducted with a dish-style concentrating photovoltaic system. The results show that the short-circuit current ( ) and the open-circuit voltage ( ) of multi-junction solar cells increases with the increasing concentration ratio, while the cell efficiency ( ) of the solar cells increases first and then decreases with increasing concentration ratio. With increasing solar cell temperature, increases, while and decrease. A comparison of the experimental and simulation results indicate that the maximum root mean square error is less than 10%, which provides a certain theoretical basis for the study of the characteristics of triple-junction solar cell that can be applied in the analysis and discussion regarding the influence of the relevant parameters on the performance of high concentration photovoltaic systems.

关键词： concentration three-junction solar cell mathematical model electrical properties solar energy

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FeNi doped porous carbon as an efficient catalyst for oxygen evolution reaction

Jun-Wei Zhang, Hang Zhang, Tie-Zhen Ren, Zhong-Yong Yuan, Teresa J. Bandosz

《化学科学与工程前沿（英文）》 2021年第15卷第2期页码 279-287 doi: 10.1007/s11705-020-1965-2

摘要： Polymer-derived porous carbon was used as a support of iron and nickel species with an objective to obtain an efficient oxygen reduction reaction (OER) catalyst. The surface features were extensively characterized using X-ray diffraction, X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy. On FeNi-modified carbon the overpotential for OER was very low (280 mV) and comparable to that on noble metal catalyst IrO . The electrochemical properties have been investigated to reveal the difference between the binary alloy- and single metal-doped carbons. This work demonstrates a significant step for the development of low-cost, environmentally-friendly and highly-efficient OER catalysts.

关键词： OER polystyrene salt porous carbon FeNi alloy p/n junction

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Ultrathin microcrystalline hydrogenated Si/Ge alloyed tandem solar cells towards full solar spectrum conversion

Yu Cao, Xinyun Zhu, Xingyu Tong, Jing Zhou, Jian Ni, Jianjun Zhang, Jinbo Pang

《化学科学与工程前沿（英文）》 2020年第14卷第6期页码 997-1005 doi: 10.1007/s11705-019-1906-0

摘要： Thin film solar cells have been proved the next generation photovoltaic devices due to their low cost, less material consumption and easy mass production. Among them, micro-crystalline Si and Ge based thin film solar cells have advantages of high efficiency and ultrathin absorber layers. Yet individual junction devices are limited in photoelectric conversion efficiency because of the restricted solar spectrum range for its specific absorber. In this work, we designed and simulated a multi-junction solar cell with its four sub-cells selectively absorbing the full solar spectrum including the ultraviolet, green, red as well as near infrared range, respectively. By tuning the Ge content, the record efficiency of 24.80% has been realized with the typical quadruple junction structure of a-Si:H/a-Si Ge :H/µc-Si:H/µc-Si Ge :H. To further reduce the material cost, thickness dependent device performances have been conducted. It can be found that the design of total thickness of 4 m is the optimal device design in balancing the thickness and the . While the design of ultrathin quadruple junction device with total thickness of 2 m is the optimized device design regarding cost and long-term stability with a little bit more reduction in . These results indicated that our solar cells combine the advantages of low cost and high stability. Our work may provide a general guidance rule of utilizing the full solar spectrum for developing high efficiency and ultrathin multi-junction solar cells.

关键词： thin films solar cells quadruple junction solar cell amorphous silicon silicon germanium alloy quantum efficiency