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Development of electron and hole selective contact materials for perovskite solar cells 被引量:1
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作者 Yaming Yu Peng Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第6期1144-1152,共9页
Nowadays,both n-i-p and p-i-n perovskite solar cells(PSCs) device structures are reported to give high performance with photo conversion efficiencies(PCEs) above 20%.The efficiency of the PSCs is fundementally det... Nowadays,both n-i-p and p-i-n perovskite solar cells(PSCs) device structures are reported to give high performance with photo conversion efficiencies(PCEs) above 20%.The efficiency of the PSCs is fundementally determined by the charge selective contact materials.Hence,by introducing proper contact materials with good charge selectivity,one could potentially reduce interfacial charge recombination as well as increase device performance.In the past few years,copious charge selective contact materials have been proposed.Significant improvements in the corresponding devices were observed and the reported PCEs were close to that of classic Spiro-OMeTAD.This mini-review summarizes the state-of-the-art progress of typical electron/hole selective contact materials for efficient perovskite solar cells and an outlook to their development is made. 展开更多
关键词 Perovskite solar cell Charge selective contact materials Energy level HTM ETM
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A ladder conjugated polymer transducer for solid-contact Cu^(2+)-selective electrodes 被引量:1
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作者 Shun-Yang Yu Yan-Cang Li +4 位作者 Tao Xiong Qun Yuan Yong-Ming Liu Zhong-Yi Yuan Yi Xiao 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第2期364-366,共3页
In recent years, there has been a pronounced interest in solid-contact ion-selective electrodes (SC-ISEs), with emphasis on the use of conducting polymers as ion-to-electron transducer. In this work, a ladder conjug... In recent years, there has been a pronounced interest in solid-contact ion-selective electrodes (SC-ISEs), with emphasis on the use of conducting polymers as ion-to-electron transducer. In this work, a ladder conjugated polymer, thieno[3,2-b]thiophene (LCPT), was investigated in fabricating Cu2+-selective electrodes for the first time. The resulting electrodes were characterized by electrochemical impedance spectroscopy (EIS), chronopotentiometry, and the water layer test. Results proved that the active LCPT facilitates the ion-to-electron transduction, and avoids the detrimental aqueous layer formed at the interface of SC-ISEs. 展开更多
关键词 Ladder polymer Solid contact Ion-selective electrode COPPER
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A highly selective solid-contact electrode for Ag^+ based on a monoazathiacrown ether ionophore 被引量:1
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作者 Shun Yang Yu Lan Ju +2 位作者 Fu Hai Li Yong Ming Liu Jun Feng Fang 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第4期488-491,共4页
A new solid-contact Ag~+-selective electrode was prepared with 9,10,12,13,24,25-hexahydro-5H,15H,23H-dibenzo [b,q][1,7,10,13,19,4,16]-entathiadiazacyclodocosine-6,16(7H,17H)-dione as ionophore,and cc,a-dihexylsexit... A new solid-contact Ag~+-selective electrode was prepared with 9,10,12,13,24,25-hexahydro-5H,15H,23H-dibenzo [b,q][1,7,10,13,19,4,16]-entathiadiazacyclodocosine-6,16(7H,17H)-dione as ionophore,and cc,a-dihexylsexithiophene(DH- 6T) ion-to-electron transducer.The sensor exhibited a working concentration range of 10~8 to 10^(-3) mol/L,with a near-Nernstian slope of 55.1±0.2 mV/dec and detection limit of 1.7×10^(-9) mol/L.The fabricated electrodes demonstrated excellent selectivity over the most common monovalent and divalent cations. 展开更多
关键词 Solid contact SILVER Ion-selective electrodes Low detection limit
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Ohmic Contact Formation for n+4H-SiC Substrate by Selective Heating Method Using Hydrogen Radical Irradiation
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作者 Tetsuji Arai Kazuki Kamimura +8 位作者 Chiaya Yamamoto Mai Shirakura Keisuke Arimoto Junji Yamanaka Kiyokazu Nakagawa Toshiyuki Takamatsu Masaaki Ogino Masaaki Tachioka Haruo Nakazawa 《Journal of Materials Science and Chemical Engineering》 2017年第1期35-41,共7页
We developed an apparatus for producing high-density hydrogen plasma. We confirmed that the temperatures of transition-metal films increased to above 800?C within 5 s when they were exposed to hydrogen plasma formed u... We developed an apparatus for producing high-density hydrogen plasma. We confirmed that the temperatures of transition-metal films increased to above 800?C within 5 s when they were exposed to hydrogen plasma formed using the apparatus. We applied this phenomenon to the selective heat treatment of W/Ni films deposited on n+4H-SiC wafers and formed nickel silicide electrodes. To utilize this method, we can perform the nickel silicidation process without heating the other areas such as channel regions and improve the reliability. 展开更多
关键词 selectIVE Heating Nickel SILICIDE Electrode HYDROGEN Plasma Ohmic contact SiC
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选择发射极对TOPCon太阳电池性能的影响研究
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作者 章康平 孙亚楠 +3 位作者 李家栋 胥星星 廖东进 黄志平 《太阳能学报》 北大核心 2026年第1期48-54,共7页
重点分析激光功率对发射区掺杂、电池暗饱和电流、接触电阻与电性能的影响。结果表明,当激光功率输出比从73%增至78%时,选择发射区整体掺杂浓度逐渐提高,与轻扩区形成145~150Ω/□方阻差,有效少子寿命、iVoc、接触电阻率等随整体杂质浓... 重点分析激光功率对发射区掺杂、电池暗饱和电流、接触电阻与电性能的影响。结果表明,当激光功率输出比从73%增至78%时,选择发射区整体掺杂浓度逐渐提高,与轻扩区形成145~150Ω/□方阻差,有效少子寿命、iVoc、接触电阻率等随整体杂质浓度的提高明显下降,而暗饱和电流的大小则受表面杂质浓度的影响更大。因而选择发射极的使用,可通过提高光吸收区的方块电阻来降低整体掺杂浓度,从而提高少子寿命和高开路电压。当激光功率输出比为75%时,暗饱和电流密度为17.68 fA/cm^(2),接触电阻率为1.34Ωcm^(2),获得最佳电池性能开路电压为723.79 mV、填充因子为84.58%、转换效率为25.51%。 展开更多
关键词 太阳电池 选择发射极 掺杂浓度 方块电阻 暗饱和电流密度 接触电阻率 电池性能
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Lighting the way:precision doping in organic semiconductors
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作者 Niansheng Xu Feng Gao 《Science China Materials》 2026年第3期1797-1798,共2页
Doping is essential for modulating semiconductor conductivity,forming p-n junctions,and reducing contact resistance[1].Notably,as organic semiconductors(OSCs)advance toward high performance,flexibility,and miniaturiza... Doping is essential for modulating semiconductor conductivity,forming p-n junctions,and reducing contact resistance[1].Notably,as organic semiconductors(OSCs)advance toward high performance,flexibility,and miniaturization,achieving precise regionally selective doping becomes critical for building complex,highly integrated devices[2].In inorganic semiconductors(e.g.,silicon),sub-100-nanometer regional doping is achievable through photolithography and ion implantation—techniques foundational to modern complementary metaloxide-semiconductor(CMOS)technology[3]. 展开更多
关键词 reducing contact resistance notablyas organic semiconductors oscs advance precision ion implantation techniques inorganic semiconductors egsilicon sub nanometer regionally selective doping LIGHTING modulating semiconductor conductivityforming
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Microstructure and properties of Ag/SnO2 functional material manufactured by selective laser melting 被引量:7
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作者 Yuanjie Zhang Bo Song +1 位作者 Xiao Zhao Yusheng Shi 《Nano Materials Science》 CAS 2019年第3期208-214,共7页
Ag/SnO2,as a promising and environment-friendly electrical contact material,is widely applied in low-voltage apparatus.But the properties of Ag/SnO2 composites is difficult to improve due to the poor distribution phas... Ag/SnO2,as a promising and environment-friendly electrical contact material,is widely applied in low-voltage apparatus.But the properties of Ag/SnO2 composites is difficult to improve due to the poor distribution phases and difficult component design.In this work,the Ag/SnO2 composites are prepared by selective laser melting.To get better performance,Ag/SnO2 composites with different energy density were studied.The microstructure was observed by field emission scanning electron microscope.In addition,reinforced SnO2 phase was characterized by X-ray diffraction and transmission electron microscope.The results indicated that the microstructure,relative density and hardness of are influenced by energy density,while Ag/SnO2 composites with homogeneous microstructure,high relative density,higher hardness and lower electrical resistivity can be obtained by proper energy density(E?68 J/mm^3). 展开更多
关键词 selectIVE laser MELTING AG/SNO2 COMPOSITES Electrical contact material
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Distributed Contact Plan Design for Multi-Layer Satellite-Terrestrial Network 被引量:3
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作者 Wenfeng Shi Deyun Gao +4 位作者 Huachun Zhou Bohao Feng Haifeng Li Guanwen Li Wei Quan 《China Communications》 SCIE CSCD 2018年第1期23-34,共12页
In multi-layer satellite-terrestrial network, Contact Graph Routing(CGR) uses the contact information among satellites to compute routes. However, due to the resource constraints in satellites, it is extravagant to co... In multi-layer satellite-terrestrial network, Contact Graph Routing(CGR) uses the contact information among satellites to compute routes. However, due to the resource constraints in satellites, it is extravagant to configure lots of the potential contacts into contact plans. What's more, a huge contact plan makes the computing more complex, which further increases computing time. As a result, how to design an efficient contact plan becomes crucial for multi-layer satellite network, which usually has a large scaled topology. In this paper, we propose a distributed contact plan design scheme for multi-layer satellite network by dividing a large contact plan into several partial parts. Meanwhile, a duration based inter-layer contact selection algorithm is proposed to handle contacts disruption problem. The performance of the proposed design was evaluated on our Identifier/Locator split based satellite-terrestrial network testbed with 79 simulation nodes. Experiments showed that the proposed design is able to reduce the data delivery delay. 展开更多
关键词 contact GRAPH ROUTING distributedcontact PLAN multi-layered SATELLITE network inter-layer contact selection
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Effects of heat input on layer heterogeneity of selective laser melting Ti-6Al-4V components 被引量:5
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作者 陈昌荣 刘畅 +4 位作者 王乾廷 练国富 黄旭 冯美艳 戴继成 《China Welding》 CAS 2023年第3期51-66,共16页
Due to the layer-by-layer manufacturing characteristics,metallurgical process of selective laser melting(SLM)is inherently dif-ferent in the building direction because of varying conditions,thereby resulting inter-lay... Due to the layer-by-layer manufacturing characteristics,metallurgical process of selective laser melting(SLM)is inherently dif-ferent in the building direction because of varying conditions,thereby resulting inter-layer heterogeneity.To mitigate such anisotropy,it is of great significance to understand the effects of processing parameters on the property evolution and thus metallurgy of fabrication process.This research proposes one-factor-at-a-time experiment to investigate the influences of laser power and scanning speed on the surface qual-ity,microstructures and mechanical properties of selective laser melted Ti-6Al-4V parts.Surface quality is assessed by roughness around the printings while mechanical properties are evaluated through microhardness and tensile strengths.Phases in microstructure are quantified by XRD to correlate with mechanical properties.Fracture morphology is analyzed to understand the effect of defects and microstructure on mechanical performance.The optimized parameter corresponding to best surface quality and mechanical properties has been found respect-ively in laser power of 190 W and scanning speed of 800 mm/s.After optimization,surface roughness has decreased by 44.47%for upper surface.Yielding strength,tensile strength and elongation rate have improved by 13.17%,43.34%and 64.51%,respectively,with similar hardness and Young’s modulus.In addition,heterogeneity of mechanical properties has great improvement by a range of 31.63%-92.68%. 展开更多
关键词 selective laser melting TI-6AL-4V inter-layer heterogeneity tensile properties heat input
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Solid-Contact Perchlorate Sensor with Nanomolar Detection Limit Based on Cobalt Phthalocyanine Ionophores Covalently Attached to Polyacrylamide 被引量:1
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作者 Mohammad Nooredeen Abbas Abdel Lattief A. Radwan +1 位作者 Philippe Bühlmann Mahmud A. Abd El Ghaffar 《American Journal of Analytical Chemistry》 2011年第7期820-831,共12页
Novel solid-contact perchlorate sensors based on cobalt phthalocyanine-C-monocarboxylic acid (I), and cobalt phthalocyanine-C,C,C,C-tetracarboxylic acid (II) as free ionophores and covalently attached to polyacryla- m... Novel solid-contact perchlorate sensors based on cobalt phthalocyanine-C-monocarboxylic acid (I), and cobalt phthalocyanine-C,C,C,C-tetracarboxylic acid (II) as free ionophores and covalently attached to polyacryla- mide (PAA)—ionophores III and IV, respectively were prepared. The all solid-state sensors were constructed by the application of a thin film of a polymer cocktail containing a phthalocyanine ionophore and cetyltrimethylammonium bromide (CTMAB) as a lipophilic cationic additive onto a gold electrode precoated with the conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT) as an ion and electron transducer. The sensor with 10.3% of ionophore (III) covalently attached to plasticizer-free poly (butyl methacrylate-co-do- decyl methacrylate) (PBDA) exhibited a good selectivity for perchlorate and discriminated many ions, in- cluding F–, Cl–, Br–, I–, SCN–, , S2– and . The covalent attachment of the ionophore to the polymer resulted in a near-Nernstian anionic slope of –62.3 mV/decade whereas a super-Nernstian slope of –79.9 mV/ decade was obtained for the free ionophore. The sensor covered a linear concentration range of 5 × 10–9 - 1 × 10–2 mol?L–1 with a lower detection limit (LDL) of 1 × 10–9 mol?L–1 and gave a stable response over a pH range of 4 - 10.5. The all-solid state sensors were utilized for the selective flow injection potentiometric determination of perchlorate in natural water and human urine samples in the nanomolar concentration range. 展开更多
关键词 Ion-selective Electrode SOLID contact Covalent IONOPHORE Attachment PERCHLORATE FLOW-INJECTION Analysis Urine
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基于机器学习的动车传动齿轮修形仿真研究 被引量:1
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作者 刘志超 黄志辉 +2 位作者 李治桦 杨成龙 陈丙硕 《制造技术与机床》 北大核心 2025年第8期87-95,共9页
动车传动齿轮在工作过程中存在齿面偏载和啮合冲击等问题,易造成齿轮失效。为改善此类问题,以CRH3动车为例,在Romax软件中建立了包含车轴和轴承的齿轮传动系统三维模型。基于RFE-XGBoost(recursive feature elimination-extreme gradien... 动车传动齿轮在工作过程中存在齿面偏载和啮合冲击等问题,易造成齿轮失效。为改善此类问题,以CRH3动车为例,在Romax软件中建立了包含车轴和轴承的齿轮传动系统三维模型。基于RFE-XGBoost(recursive feature elimination-extreme gradient boosting)特征选取模型,从通常采用的9个修形参数中筛选出最优修形参数组合。以筛选后的最优修形参数组合为输入变量,单位长度法向载荷为响应变量,分别基于反向传播(back propagation,BP)神经网络神经网络、随机森林回归、XGBoost算法构建了代理模型,并进行对比选择。最后采用粒子群优化(particle swarm optimization,PSO)算法调用代理模型,以单位长度法向载荷最小为优化目标,对齿轮修形参数取值进行寻优计算。优化结果表明,齿向斜度为13.6μm、齿端修薄长度为18.5 mm、齿端修薄量为4.4μm时齿轮修形效果最佳。通过Romax仿真计算验证,其单位长度法向载荷下降了24.36%,传动误差值下降了69.91%,有效改善了齿轮传动性能,缓解了齿面偏载的现象。研究结果可为齿轮修形方案选择和优化设计提供参考。 展开更多
关键词 动车传动齿轮 特征选取 齿轮修形 XGBoost算法 齿面接触分析
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基于金属氧化物载流子选择性传输层的硅异质结太阳电池的研究进展
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作者 胡梦琪 苏炬 +3 位作者 王光红 刁宏伟 赵雷 王文静 《太阳能学报》 北大核心 2025年第3期342-347,共6页
晶硅异质结(HJT)太阳电池的转换效率已达到26.81%,然而其使用有毒有害气体掺杂的传输层存在不可避免的寄生吸收损失,阻止了器件性能的进一步提升。因此,宽带隙非掺杂的钝化接触太阳电池受到极大关注。该文对载流子选择性传输原理、非掺... 晶硅异质结(HJT)太阳电池的转换效率已达到26.81%,然而其使用有毒有害气体掺杂的传输层存在不可避免的寄生吸收损失,阻止了器件性能的进一步提升。因此,宽带隙非掺杂的钝化接触太阳电池受到极大关注。该文对载流子选择性传输原理、非掺杂钝化接触材料及其主要沉积方法、非掺杂空穴/电子选择性材料的研究现状及器件稳定性改善方式进行概述,并对钝化接触型非掺杂晶硅异质结太阳电池存在的问题和前景进行讨论。 展开更多
关键词 载流子传输 过渡金属氧化物 硅太阳电池 载流子选择性接触 异质结太阳电池 非掺杂 异质结太阳电池 非掺杂
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晶体硅太阳电池的BaFx电子选择性接触研究
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作者 狄翀 李文昊 +3 位作者 陈静伟 丁阳 韦德远 许颖 《太阳能学报》 北大核心 2025年第6期245-250,共6页
研究一种利用电子束蒸发方法制备的超薄氟化钡(BaF_(x))薄膜的材料特性,并将其应用为晶体硅异质结电池的新颖的、输运电子而阻挡空穴的免掺杂选择性接触传输材料。紫外光电子能谱测试表明BaF_(x)/Al界面的功函数为2.55 eV,低于铝本身的... 研究一种利用电子束蒸发方法制备的超薄氟化钡(BaF_(x))薄膜的材料特性,并将其应用为晶体硅异质结电池的新颖的、输运电子而阻挡空穴的免掺杂选择性接触传输材料。紫外光电子能谱测试表明BaF_(x)/Al界面的功函数为2.55 eV,低于铝本身的功函数(4.26 eV),可实现对电子的选择性传输功能。加入BaF_(x)导致Al电极和晶体硅之间形成欧姆接触,并实现23.98 mΩ·cm^(2)的低接触电阻率。将此异质结构作为轻掺杂n型单晶硅太阳电池的免掺杂整背面欧姆接触,使电池的填充因子和短路电流密度都有所提升,并最终实现电池的绝对能量转换效率2.53%的提升。 展开更多
关键词 太阳电池 硅异质结 免掺杂 电子选择性接触
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一种节能型异丁烯选择性叠合工艺的研究与探讨 被引量:1
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作者 刘成军 吕晓东 +3 位作者 孙龙江 周璇 李倞琛 于海霞 《中外能源》 CAS 2025年第1期85-90,共6页
提供了一种节能型异丁烯选择性叠合工艺。碳四原料与气相产物在接触式缓冲罐内逆流接触并进行传质和传热,然后触后气相产物进入反应分离塔,触后碳四原料与二异丁烯共沸物、脱氧水混合后作为反应进料一并进入接触式反应器。接触式反应器... 提供了一种节能型异丁烯选择性叠合工艺。碳四原料与气相产物在接触式缓冲罐内逆流接触并进行传质和传热,然后触后气相产物进入反应分离塔,触后碳四原料与二异丁烯共沸物、脱氧水混合后作为反应进料一并进入接触式反应器。接触式反应器设有液位调节器,用于确保叠合反应始终在液相状态下操作,反应完成后该反应器气相产物至接触式缓冲罐进行传质和传热,液相产物至反应分离塔进行分离和深度反应。反应分离塔包含反应段,反应段采用水、水与异丁烯反应生成的叔丁醇作复合抑制剂;在分馏的作用下,剩余碳四、二异丁烯共沸物,二异丁烯产品分别自塔顶、侧线、塔底分出。该异丁烯选择性叠合工艺具有接触式反应器反应效率高、反应热全部用于组分的传质传热、反应分离塔反应段不需设置叔丁醇二次注入设施等特点,可提高二异丁烯选择性并可大幅度降低装置能耗。 展开更多
关键词 选择性叠合 反应热 二异丁烯 传质传热 共沸物 复合抑制剂 物流性质 物料平衡 接触 节能
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报废银钨类合金触点回收工艺研究及设备选型 被引量:1
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作者 代林涛 周克武 +2 位作者 林应涛 王宝锋 柏小平 《电工材料》 2025年第2期34-36,共3页
以报废银钨类合金触点为原料,针对“一次酸溶—过滤清洗—破碎—氧化焙烧—二次酸溶—过滤清洗-银回收”的回收工艺,考察其工艺条件并进行设备选型。结果表明,采用电加热回转炉作为氧化焙烧设备,采用压滤机作为过滤洗涤设备,在钨氧化温... 以报废银钨类合金触点为原料,针对“一次酸溶—过滤清洗—破碎—氧化焙烧—二次酸溶—过滤清洗-银回收”的回收工艺,考察其工艺条件并进行设备选型。结果表明,采用电加热回转炉作为氧化焙烧设备,采用压滤机作为过滤洗涤设备,在钨氧化温度300℃,硝酸浓度7 mol/L,酸溶温度80℃,一次酸溶时间2 h,二次酸溶时间30 min的条件下可达到最佳回收效果,同时保证成本最低。 展开更多
关键词 报废银钨类合金触点 回收利用 设备选型
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基于过热故障仿真的高压开关柜测温点优化方法
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作者 吴小忠 甘星 +4 位作者 严亚兵 王玘 孟卓 钟家勇 谭智毅 《西安工程大学学报》 2025年第6期128-138,共11页
实际工作中,用户对高压开关柜热故障关注不足及测温点选取方法存在缺陷,无法对潜在热故障做到及时预警,使得高压开关柜过热故障事故呈逐年上升的趋势,因此提出一种基于有限元温度场仿真的测温点优化方法,以解决现有研究对散热风机故障... 实际工作中,用户对高压开关柜热故障关注不足及测温点选取方法存在缺陷,无法对潜在热故障做到及时预警,使得高压开关柜过热故障事故呈逐年上升的趋势,因此提出一种基于有限元温度场仿真的测温点优化方法,以解决现有研究对散热风机故障及测点选取关注不足的问题。首先,选用KYN28A-12型4000A开关柜为研究对象,采用CATIA建模软件搭建该型号开关柜几何模型,将几何模型导入ANSYS Workbench有限元仿真软件,对高压开关柜关键温升部位进行精细化网格划分后进行有限元温度场仿真计算;其次,仿真模拟了散热风机故障(单/双/三风机停运)与接触故障(触头氧化、母排搭接异常等)共8种故障工况下的温度场分布情况;最后,构建传感器覆盖率评价模型,采用改进粒子群算法优化测点布局。仿真结果表明:当三风机故障时,柜内最高温度达114.12℃;当发生接触故障时,柜内最高温度均有较大变化,经测温点优化后的5传感器布局方案覆盖率提升至84.7%,较传统布置方式检测效率提高16.5%。该文的测温点优化方法能精准表征故障温度场特征,优化后的测点布局兼顾成本与监测效能,为工程实践提供理论借鉴。 展开更多
关键词 高压开关柜 温度场 过热故障 测点选取 接触故障
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选择性相强化对CuCr触头材料在真空小间隙中耐电压强度的影响 被引量:14
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作者 王亚平 张丽娜 +1 位作者 丁秉钧 周敬恩 《中国电机工程学报》 EI CSCD 北大核心 1999年第3期46-49,共4页
研究了合金元素W、Co的加入对CuCr触头材料在真空小间隙中耐电压强度的影响。研究结果表明,合金元素选择强化CuCr材料的Cr相能够显著提高触头间隙的耐电压强度,而强化Cu相对间隙的耐电压强度没有明显作用。文章认为制... 研究了合金元素W、Co的加入对CuCr触头材料在真空小间隙中耐电压强度的影响。研究结果表明,合金元素选择强化CuCr材料的Cr相能够显著提高触头间隙的耐电压强度,而强化Cu相对间隙的耐电压强度没有明显作用。文章认为制备CuCr系触头材料时应选择适当的制备工艺,使合金元素能够选择强化材料中的Cr相。 展开更多
关键词 触头材料 CUCR 耐电压强度 真空 选择性相强化
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接触反应钎焊中间层材料的选择原则——接触反应共晶液相产生的方向性 被引量:7
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作者 董占贵 钱乙余 +1 位作者 马鑫 石素琴 《中国有色金属学报》 EI CAS CSCD 北大核心 2002年第2期241-244,共4页
以Al/Cu ,Al/Si接触反应偶为例 ,研究了不同基体与反应材料组合下 ,共晶液相的产生及其铺展行为。结果表明 :Al/Cu ,Al/Si接触反应偶中共晶液相的产生具有明显的方向性—优先在Al侧产生 ,这是扩散偶之间的互扩散系数不等所造成的必然结... 以Al/Cu ,Al/Si接触反应偶为例 ,研究了不同基体与反应材料组合下 ,共晶液相的产生及其铺展行为。结果表明 :Al/Cu ,Al/Si接触反应偶中共晶液相的产生具有明显的方向性—优先在Al侧产生 ,这是扩散偶之间的互扩散系数不等所造成的必然结果。而在接触反应钎焊的中间层材料选择过程中 。 展开更多
关键词 接触反应钎焊 AL/CU 接触反应偶 共晶反应 中间层选择 液相合金 Al/Si
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CuCr25W1Col合金的性能研究 被引量:11
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作者 赵峰 杨志懋 丁秉钧 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2000年第1期57-60,共4页
为节约Cr资源,提高CuCr触头材料的耐电击穿性能并满足其大规模生产的需要,根据W、Co的选择相强化作用,以纯Cu、Cr块为原料,采用Ar气保护熔炼法制备CuCr25W1Col触头合金,并对其性能进行研究。实验结果表明,该合金晶粒尺寸细小,含气量低,... 为节约Cr资源,提高CuCr触头材料的耐电击穿性能并满足其大规模生产的需要,根据W、Co的选择相强化作用,以纯Cu、Cr块为原料,采用Ar气保护熔炼法制备CuCr25W1Col触头合金,并对其性能进行研究。实验结果表明,该合金晶粒尺寸细小,含气量低,耐电压强度已达到常规触头材料的水平。 展开更多
关键词 CUCR 触头材料 选择相强化 耐电压强度
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空间机器人在轨更换ORU的力/位混合控制方法 被引量:22
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作者 徐文福 周瑞兴 孟得山 《宇航学报》 EI CAS CSCD 北大核心 2013年第10期1353-1361,共9页
针对ORU在轨更换任务,首先推导了空间机械臂末端自由、末端与环境接触等情况下的动力学方程,并提出了相应的接触力计算方法;其次,改进了传统的R-C控制方法,采用加权选择矩阵代替原有的选择矩阵,实现了力控制与位置控制之间的平滑切换;最... 针对ORU在轨更换任务,首先推导了空间机械臂末端自由、末端与环境接触等情况下的动力学方程,并提出了相应的接触力计算方法;其次,改进了传统的R-C控制方法,采用加权选择矩阵代替原有的选择矩阵,实现了力控制与位置控制之间的平滑切换;最后,开发了基于Matlab/Simulink的闭环控制仿真系统,该系统由多体动力学、接触动力学、轨迹规划、力/位混合控制、3D显示等模块组成。利用该系统开展了ORU转移与安装过程的闭环控制仿真,仿真结果校验了所提方法的有效性。 展开更多
关键词 空间机器人 位混合控制 ORU更换 接触动力学 选择矩阵
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