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开放的复杂巨系统 9

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Enhancement of open circuit voltage in organic solar cells by doping a fluorescent red dye

Qing LI, Junsheng YU, Yue ZANG, Nana WANG, Yadong JIANG

《能源前沿（英文）》 2012年第6卷第2期页码 179-183 doi: 10.1007/s11708-012-0177-y

摘要： The open circuit voltage ( ) of small-molecule organic solar cells (OSCs) could be improved by doping suitable fluorescent dyes into the donor layers. In this paper, 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) was used as a dopant, and the performance of the OSCs with different DCJTB concentration in copper phthalocyanine (CuPc) was studied. The results showed that the of the OSC with 50% of DCJTB in CuPc increased by 15%, compared with that of the standard CuPc/fullerene (C ) device. The enhancement of the was attributed to the lower highest occupied molecular orbital (HOMO) level in the DCJTB than that in the CuPc. Also, the light absorption intensity is enhanced between 400 and 550 nm, where CuPc and C have low absorbance, leading to a broad absorption spectrum.

关键词： organic solar cells (OSCs) open circuit voltage fluorescent dye doping 4-(dicyanomethylene)-2-t-butyl-6-(1 1 7 7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB)

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单边直线感应电机等效电路参数研究

徐伟,孙广生

《中国工程科学》 2008年第10卷第8期页码 76-80

摘要：

单边直线感应电机（SLIM）相对于旋转感应电机（RIM）存在气隙大、边缘效应等，若采用RIM开路和短路试验方法，会给参数测量带来较大误差。文章提出的一种适合SLIM参数测定的新型方案，只需测量电机输入端的总功率、相电压、相电流和频率4个量，即可计算出初级电阻、初级漏感、次级电阻、次级漏感、气隙电感和铁损电阻。电机的特性分析表明，该方法真实有效，具有一定的参考价值。

关键词：单边直线感应电机开路试验短路试验参数测量等效电路

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Experimental investigation and comparative study of inter-turn short-circuits and unbalanced voltage

Fatima BABAA, Abdelmalek KHEZZAR, Mohamed el kamel OUMAAMAR

《能源前沿（英文）》 2013年第7卷第3期页码 271-278 doi: 10.1007/s11708-013-0258-6

摘要： A transient model for an induction machine with stator winding turn faults on a single phase is derived using reference frame transformation theory. The negative sequence component and the 3rd harmonic are often considered as accurate indicators. However, small unbalance in the supply voltage and/or in the machine structure that exists in any real system engenders the same harmonics components. In this case, it is too difficult to distinguish between the current harmonics due to the supply voltage and those originated by inter-turn short-circuit faults. For that, to have the correct diagnosis and to increase the sensitivity and the reliability of the diagnostic system, it is crucial to provide the relationship between the inter-turn short-circuits in the stator winding and the supply voltage imbalance through an accurate mathematical model and via a series of experimental essays.

关键词： induction machines fault indicator inter-turn short-circuit fault unbalance supply voltage

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一种具有高电压传输比的新型Cuk矩阵变换器

张小平,朱建林,唐华平,张炳根,柳莎莎

《中国工程科学》 2008年第10卷第4期页码 78-83

摘要：

对传统矩阵变换器存在电压传输比低的缺陷进行研究，提出一种新型的称为Cuk矩阵变换器的电路拓扑结构。介绍了该拓扑结构的基本构成及其工作原理，推导了其电压传输比与占空比之间函数关系的解析表达式，阐述了所采用的双闭环控制策略的基本设计方法，并通过仿真对其有效性和可行性进行了验证。结果表明：该拓扑结构能实现输出电压和频率的任意调节，其电压传输比可大于1，也可小于1，且直接输出标准的正弦波而无需滤波环节，有效地解决了传统矩阵变换器电压传输比低的难题，具有一定的应用价值。

关键词： Cuk矩阵变换器电路拓扑电压传输比双闭环控制仿真

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低压断路器和漏电保护电器的可靠性研究

陆俭国

《中国工程科学》 2005年第7卷第6期页码 36-40

摘要：

阐述了低压断路器和漏电保护电器等低压保护类电器可靠性研究的重要性、科学意义及其社会效益，介绍了国际上权威学术机构IEEE在该方面所做工作的概况，指出了开展该方面研究工作的难度与创新意义；重点分析了低压断路器和漏电保护电器的故障模式，在此基础上，在国内外首次提出了其可靠性指标与可靠性验证试验方案，为我国电器行业开展低压保护类电器的可靠性工作提出了理论依据与具体方法。

关键词：故障模式可靠性指标可靠性验证试验方案

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基于混沌电路电容器连接的微分耦合同步 Regular Papers

Yu-meng XU, Zhao YAO, Aatef HOBINY, Jun MA

《信息与电子工程前沿（英文）》 2019年第20卷第4期页码 571-583 doi: 10.1631/FITEE.1800499

摘要：非线性振子和电路常用于研究耦合同步和一致性问题。完全同步是指所有振子保持相同幅度和相位，主要发生在完全相同振子之间。相位同步是指振子保持步调节律同步而幅度不同。对于无维动力学系统和振子，同步依赖于耦合变量的选择和耦合方式。非线性电路中电阻常用于连接两个或以上电路，触发电压耦合可对耦合电路反馈调制。本文采用电容器耦合两个Pikovsk-Rabinovich(PR)电路，这种电场耦合机制为微分耦合提供了依据。讨论了对称性和错位耦合下两个混沌电路的同步稳定性问题。在电阻耦合下，两个混沌电路容易完全同步。进一步讨论电容器耦合，发现当耦合电容器选择合适电容值时，两个耦合电路同步可被有效控制，且耦合电容器能量流有助于对同步的调控。混沌电路的同步实现和耦合通道有关，如对称性耦合容易完全同步，错位耦合有利于相位同步。电容器对应电场耦合能降低耦合器件能量（焦耳热）消耗，加强两个耦合电路能量输运和交换，从而实现混沌电路同步。

关键词：同步；电压耦合；混沌电路；电容器耦合

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Self-catalytic pyrolysis thermodynamics of waste printed circuit boards with co-existing metals

《环境科学与工程前沿（英文）》 2022年第16卷第11期 doi: 10.1007/s11783-022-1581-0

摘要：

● The co-existing metals in WPCBs has positive catalytic influence in pyrolysis.

关键词： Waste printed circuit board Catalyst Pyrolysis Kinetics

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Design and analyses of open-ended pipe piles in cohesionless soils

Yuan GUO,Xiong (Bill) YU

《结构与土木工程前沿（英文）》 2016年第10卷第1期页码 22-29 doi: 10.1007/s11709-016-0314-5

摘要： Large open-ended pipe pile has been found to be advantageous for use in transportation projects. The current design method, however, is not adequately developed. To close this practice gap, this paper first summarized different design methods for open-ended pipe piles in sandy soils. A major factor for all the design codes is to properly account for the formation and effects of soil plug. The comparison indicates that there is a large variation in the base capacity evaluation among different methods due to the complex behaviors of soil plug. To close the knowledge gap, discrete element method (DEM) was used to simulate the soil plugging process and provide insight on the plugging mechanism. The simulation results show that the arching effect significantly increases the internal unit shear resistance along pipe piles. The porosity distribution and particle contact force distribution from DEM model indicate a large stress concentration occurs at the bottom of the soil plug. Besides, nearly 90% of the plug resistance is provided by the bottom half portion of the soil column. The soil-pile friction coefficient has a significant effect on the magnitude of plug resistance, with the major transition occurred for friction coefficient between 0.3 and 0.4.

关键词： open-ended pipe pile soil plug DEM base capacity

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Thermal response of steel framing members in open car park fires

Xia YAN; Marion CHARLIER; Thomas GERNAY

《结构与土木工程前沿（英文）》 2022年第16卷第9期页码 1071-1088 doi: 10.1007/s11709-022-0879-0

摘要： For open car park structures, adopting a performance-based structural fire design is often justified and allowed because the fire does not reach flashover. However, this design approach requires an accurate assessment of temperatures in structural members exposed to car fires. This paper describes a numerical study on the thermal exposure on steel framing members in open car park fires. Steel temperatures are computed by the coupling of computational fluid dynamics and finite element modeling, and by analytical models from the Eurocodes. In addition, the influence of galvanization on the steel temperature evolution is assessed. Results show that temperatures in unprotected beams and columns are influenced by the section geometry, car fire scenario, modeling approach, and use of galvanization. Galvanization slightly delays and reduces peak temperature. Regarding the different models, CFD-FEM (CFD: computational fluid dynamics, FEM: finite-element method) coupled models predict lower temperatures than the Hasemi model, because the latter conservatively assumes that the fire flame continuously touches the ceiling. Further, the Hasemi model cannot account for the effect of reduced emissivity from galvanization on the absorbed heat flux. Detailed temperature distributions obtained in the steel members can be used to complete efficient structural fire designs based on the member sections, structure layout, and use of galvanization.

关键词： open car park localized fire steel frame numerical modeling computational fluid dynamics

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Non-toxic, high selectivity process for the extraction of precious metals from waste printed circuit

《环境科学与工程前沿（英文）》 2023年第17卷第10期 doi: 10.1007/s11783-023-1723-z

摘要：

● Au, Ag and Pd were recovered from WPCBs with high efficiencies.

关键词： Thiosulfate Printed circuit boards Precious metals Leaching Hydrometallurgy

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Equivalent circuit and characteristic simulation of a brushless electrically excited synchronous wind

Hao WANG, Fengge ZHANG, Tao GUAN, Siyang YU

《机械工程前沿（英文）》 2017年第12卷第3期页码 420-426 doi: 10.1007/s11465-017-0439-9

摘要：

A brushless electrically excited synchronous generator (BEESG) with a hybrid rotor is a novel electrically excited synchronous generator. The BEESG proposed in this paper is composed of a conventional stator with two different sets of windings with different pole numbers, and a hybrid rotor with powerful coupling capacity. The pole number of the rotor is different from those of the stator windings. Thus, an analysis method different from that applied to conventional generators should be applied to the BEESG. In view of this problem, the equivalent circuit and electromagnetic torque expression of the BEESG are derived on the basis of electromagnetic relation of the proposed generator. The generator is simulated and tested experimentally using the established equivalent circuit model. The experimental and simulation data are then analyzed and compared. Results show the validity of the equivalent circuit model.

关键词： wind power brushless electrically excited synchronous generator hybrid rotor equivalent circuit

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Analysis of the double-layer α-Si:H emitter with different doping concentrations for α-Si:H/c-Si heterojunction solar cells

Haibin HUANG,Gangyu TIAN,Tao WANG,Chao GAO,Jiren YUAN,Zhihao YUE,Lang ZHOU

《能源前沿（英文）》 2017年第11卷第1期页码 92-95 doi: 10.1007/s11708-016-0432-8

摘要： Double-layer emitters with different doping concentrations (DLE) have been designed and prepared for amorphous silicon/crystalline silicon (α-Si:H/c-Si) heterojunction solar cells. Compared with the traditional single layer emitter, both the experiment and the simulation (AFORS-HET, http://www.paper.edu.cn/html/releasepaper/2014/04/282/) prove that the double-layer emitter increases the short circuit current of the cells significantly. Based on the quantum efficiency (QE) results and the current-voltage-temperature analysis, the mechanism for the experimental results above has been investigated. The possible reasons for the increased current include the enhancement of the QE in the short wavelength range, the increase of the tunneling probability of the current transport and the decrease of the activation energy of the emitter layers.

关键词： double-layer emitter α-Si:H/c-Si heterojunction solar cell short circuit current quantum efficiency current-voltage-temperature

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Parameter identification of interconnected power system frequency after trip-out of high voltage transmission

Xuzhan ZHOU,Shanshan LIU,Mingkun WANG,Yiping DAI,Yaohua TANG

《能源前沿（英文）》 2014年第8卷第3期页码 386-393 doi: 10.1007/s11708-014-0323-9

摘要： Accurate modeling and parameters of high voltage (HV) grid are critical for stability research of system frequency. In this paper, simulation modeling of the system frequency was conducted of an interconnected power system with HV transmission lines in China. Based on recorded tripping data of the HV transmission lines, system parameters were identified by using genetic algorithm (GA). The favorable agreement between simulation results and recorded data verifies the validity of gird models and the accuracy of system parameters. The results of this paper can provide reference for the stability research of HV power grid.

关键词： high voltage (HV) grid frequency stability parameter identification primary frequency regulation (PFR)

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Recent advances toward high voltage, EC-free electrolytes for graphite-based Li-ion battery

Tong Zhang, Elie Paillard

《化学科学与工程前沿（英文）》 2018年第12卷第3期页码 577-591 doi: 10.1007/s11705-018-1758-z

摘要：

Lithium-ion batteries are a key technology in today’s world and improving their performances requires, in many cases, the use of cathodes operating above the anodic stability of state-of-the-art electrolytes based on ethylene carbonate (EC) mixtures. EC, however, is a crucial component of electrolytes, due to its excellent ability to allow graphite anode operation–also required for high energy density batteries–by stabilizing the electrode/electrolyte interface. In the last years, many alternative electrolytes, aiming at allowing high voltage battery operation, have been proposed. However, often, graphite electrode operation is not well demonstrated in these electrolytes. Thus, we review here the high voltage, EC-free alternative electrolytes, focusing on those allowing the steady operation of graphite anodes. This review covers electrolyte compositions, with the widespread use of additives, the change in main lithium salt, the effect of anion (or Li salt) concentration, but also reports on graphite protection strategies, by coatings or artificial solid electrolyte interphase (SEI) or by use of water-soluble binder for electrode processing as these can also enable the use of graphite in electrolytes with suboptimal intrinsic SEI formation ability.

关键词： lithium-ion electrolyte solid electrolyte interphase additives high voltage graphite

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NC flame pipe cutting machine tool based on open architecture CNC system

Xiaogen NIE, Yanbing LIU

《机械工程前沿（英文）》 2009年第4卷第2期页码 147-152 doi: 10.1007/s11465-009-0025-x

摘要： Based on the analysis of the principle and flame movement of a pipe cutting machine tool, a retrofit NC flame pipe cutting machine tool (NFPCM) that can meet the demands of cutting various pipes is proposed. The paper deals with the design and implementation of an open architecture CNC system for the NFPCM, many of whose aspects are similar to milling machines; however, different from their machining processes and control strategies. The paper emphasizes on the NC system structure and the method for directly creating the NC file according to the cutting type and parameters. Further, the paper develops the program and sets up the open and module NC system.

关键词： flame pipe cutting flame incision tracks CNC open architecture CNC system