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骨关节炎滑液中肿瘤坏死因子α活性检测及滑膜组织超微结构观察 被引量:12
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作者 邓廉夫 柴本甫 +1 位作者 李慧 齐进 《中华外科杂志》 CAS CSCD 北大核心 1998年第2期77-79,I014,共3页
目的进一步探讨滑膜参与骨关节炎病理进程的机理。方法采用L929细胞毒活性法检测了24例急、慢性关节内损伤及晚期骨关节炎(OA)患者关节滑液中肿瘤坏死因子(TNF-α)生物活性,并用光镜和电镜观察比较三者滑膜组织间的形... 目的进一步探讨滑膜参与骨关节炎病理进程的机理。方法采用L929细胞毒活性法检测了24例急、慢性关节内损伤及晚期骨关节炎(OA)患者关节滑液中肿瘤坏死因子(TNF-α)生物活性,并用光镜和电镜观察比较三者滑膜组织间的形态学差异。结果OA滑液中所含TNF-α水平较高;OA滑膜细胞性内膜,细胞增殖与脱落同时发生,内膜下层呈现明显的纤维增生性变、滑膜增厚;B型和A型滑膜细胞的超微结构变化分别呈现旺盛的蛋白分泌相和活跃的吞噬功能。结论OA滑膜细胞的功能改变是其滑液中TNF-α升高的原因之一;滑膜的变性既可受变性软骨产物的介导,又可导致OA的进展。 展开更多
关键词 骨关节炎 滑液 肿瘤坏死因子 滑膜 超微结构
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Electrophysiology and behavior feedback of diamondback moth,Plutella xylostella,to volatile secondary metabolites emitted by Chinese cabbage 被引量:9
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作者 HAN Baoyu ZHANG Zhongning FANG Yuling 《Chinese Science Bulletin》 SCIE EI CAS 2001年第24期2086-2088,共3页
The volatiles, absorbed by Porapak Q and eluted by hexane, from Chinese cabbage, Brassica campestris chinesis (L.) Makino. van communis Tsen et Lee, have been identified as allyl isothiocyanate, Z-3-hexenyl acetate, 3... The volatiles, absorbed by Porapak Q and eluted by hexane, from Chinese cabbage, Brassica campestris chinesis (L.) Makino. van communis Tsen et Lee, have been identified as allyl isothiocyanate, Z-3-hexenyl acetate, 3,7-dimethyl-l,3,6-octatriene, 2,5-hexanediol, Z-3-hexen-l-ol, nonanol, β-myrcene, α-pinene, E-2-hexen-l-ol, D-limonene, Z-3-hexenyl propanoate, linalool, geraniol, E-4-hexen-l-ol, Z-3-hexenyl isovalerate, α-terpinene, β-caryophyllene, 3-carene and α-caryophyllene, by their mass spectra and retention times in comparison with authentic samples. The first five chemicals are the main components. All components can elicite electroantennogram (EAG) responses of dia-mondback moth (DBM), Plutella xylostella, in which allyl isothiocyanate and C6 alcohols and esters, i.e. Z-3-hexen-l-ol, E-2-hexen-l-ol, E-4-hexen-l-ol, Z-3-hexenyl isovalerate and 2,5-hexanediol elicite stronger EAG responses than other components, and EAG responses of female moths to them are slightly larger than those of male 展开更多
关键词 Chinese CABBAGE diamondback MOTH VOLATILES elec- troantennogram wind tunnel directional fly.
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CRYSTAL STRUCTURE AND ELECTROCHEMICAL PROPERTIES OF Zr(Mn_(1-x)Ni_x)_2(0.40≤x≤0.75) HYDROGEN STORAGE ALLOYS 被引量:4
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作者 W.K. Zhang, C.A. Ma, X.G. Yang, H. Huang, Y.Q. Lei and Q.D. Wang (Department of Applied Chemistry, Zhejiang University of Technology, Hangzhou 310014, China Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第1期56-62,共7页
The crystal structure, phase abundance and the electrochemical properties of Zr(Mn1-x Nix)2 (0.40 ≤x≤0.75) alloys were investigated by means of XRD, Rietveld refinement method and electrochemical measurements. The a... The crystal structure, phase abundance and the electrochemical properties of Zr(Mn1-x Nix)2 (0.40 ≤x≤0.75) alloys were investigated by means of XRD, Rietveld refinement method and electrochemical measurements. The alloys are multiphase. C15 Laves phase occurs as a main phase accompanying with C14 phase and other minor phases, indicating that Ni element is C15-stabilized element for ZrMn2 alloy. The phase abundance and lattice parameters of Laves phase are influenced significantly by Ni substitution. The Zr(Mn0.45 Ni0.55)2 alloy with the highest amount of C15 phase exhibits the maximum electrochemical capacity of 242m Ah/g. C14 phase occurring in Zr-Mn-Ni alloys is beneficial for the electrochemical kinetics of hydride electrodes. 展开更多
关键词 hydrogen storage alloy crystal structure phase abundance elec- trochemical property
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Developing a Nano-Biosensor for DNA Hybridization Using a New Electroactive Label 被引量:2
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作者 Raoof, Jahan Bakhsh Ojani, Reza Ebrahimi, Maryam Hamidi-Asl, Ezat 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第11期2541-2551,共11页
Development of electrochemical DNA hybridization biosensors based on carbon paste electrode (CPE) and gold nanoparticle modified carbon paste electrode (NGMCPE) as transducers and ethyl green (EG) as a new elect... Development of electrochemical DNA hybridization biosensors based on carbon paste electrode (CPE) and gold nanoparticle modified carbon paste electrode (NGMCPE) as transducers and ethyl green (EG) as a new electroac- tive label is described. Electrochemical impedance spectroscopy and cyclic voltammetry techniques were applied for the investigation and comparison of bare CPE and NGMCPE surfaces. Our voltammetric and spectroscopic studies showed gold nanoparticles are enable to facilitate electron transfer between the accumulated label on DNA probe modified electrode and electrode surface and enhance the electrical signals and lead to an improved detection limit. The immobilization of a 15-mer single strand oligonucleotide probe on the working electrodes and hybridiza- tion event between the probe and its complementary sequence as a target were investigated by differential pulse voltammetry (DPV) responses of the EG accumulated on the electrodes. The effects of some experimental variables on the performance of the biosensors were investigated and optimum conditions were suggested. The selectivity of the biosensors was studied using some non-complementary oligonucleotides. Finally the detection limits were calculated as 1.35×10^-10 mol/L and 5.16×10^-11 mol/L on the CPE and NEGCPE, respectively. In addition, the bio-sensors exhibited a good selectivity, reproducibility and stability for the determination of DNA sequences. 展开更多
关键词 ethyl green hybridization detection DNA recognition gold nanoparticle modified carbon paste elec- trode biosensors NUCLEOTIDES
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Voltammmetric Determination of Uric Acid in the Presence of Ascorbates Using Overoxidized Polypyrrole Film Coated Glassy Carbon Electrodes 被引量:2
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作者 KANG Tian-fang , SHEN Guo-li, YU Ru-qin (Department of Chemistry and Chemical Engineering,Hunan University, Changsha, , 410082) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第3期207-214,共8页
The voltammetric behaviour of uric acid at overoxidized polypyrrole (OPPY ) film-coated glassy carbon (GC ) electrodes was investigaied. The chemically modi- fied electrodes exhilbited an excellent permselectivity for... The voltammetric behaviour of uric acid at overoxidized polypyrrole (OPPY ) film-coated glassy carbon (GC ) electrodes was investigaied. The chemically modi- fied electrodes exhilbited an excellent permselectivity for uric acid of undissociated form in an acidic medium. The current response sensitivity of uric acid at the modi- fied electrodes was markedly increased by properly anodizing activation of underly- ing electrodes and overoxidizing treatment of polypyrrole film. The voltammetric response of uric acid at the chemically modified electrode was linearly related to itinvestigatedtion in the range of 4. 0 ×10-7 -8. 0 ×10-5 mol/L in pH 5 buffer solu- tions. Ascorbic acid in less than 150-fold excess did not interfere with the voltam- metric determination of uric acid. The proposed procedure was utilized to determine uric acicl in human urine and serum samples without any pretreatment. 展开更多
关键词 Voltammetry . Uric acid Overoxidized polypyrrole film modified elec- trode
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Development of a human computer Interface system using EOG 被引量:1
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作者 Zhao Lv Xiao-Pei Wu +1 位作者 Mi Li De-Xiang Zhang 《Health》 2009年第1期39-46,共8页
Bio-based human computer interface (HCI) has attracted more and more attention of researches all over the world in recent years. In this paper, a HCI system which based on electrooculogram (EOG) is proposed. It transf... Bio-based human computer interface (HCI) has attracted more and more attention of researches all over the world in recent years. In this paper, a HCI system which based on electrooculogram (EOG) is proposed. It transforms electrical po-tentials recorded by horizontal and vertical EOG into a computer in order to control external equipment. The system consists of EOG acqui-sition unit, EOG pattern recognition part and control command output unit. Three plane elec-trodes are employed to detect EOG signals, which contain the information related to the eye blinking and vertical (or horizontal) eye move-ments referred to pre-designed command table. An online signal processing algorithm is de-signed to get the command information con-tained in EOG signals, and these commands could be used to control the computer or other instruments. Based on this HCI system, the remote control experiments driven by EOG are realized. 展开更多
关键词 HUMAN COMPUTER INTERFACE (HCI) elec- trooculogram (EOG) BLINKING Eye Movements
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Investigation of the mode splitting induced by electro-optic birefringence in a vertical-cavity surface-emitting laser by polarized electroluminescence 被引量:1
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作者 章杰 俞金玲 +2 位作者 程树英 赖云锋 陈涌海 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期457-460,共4页
The mode splitting induced by electro-optic birefringence in a P-I-N InGaAs/GaAs/A1GaAs vertical-cavity surface- emitting laser (VCSEL) has been studied by polarized electroluminescence (EL) at room temperature. T... The mode splitting induced by electro-optic birefringence in a P-I-N InGaAs/GaAs/A1GaAs vertical-cavity surface- emitting laser (VCSEL) has been studied by polarized electroluminescence (EL) at room temperature. The polarized EL spectra with E||[110] and E || [150] directions, are extracted for different injected currents. The mode splitting of the two orthogonal polarized modes for a VCSEL device is determined, and its value increases linearly with the increasing injected current due to electro-optic birefringence; This article demonstrates that the polarized EL is a powerful tool to study the mode splitting and polarization anisotropy of a VCSEL device. 展开更多
关键词 mode splitting electro-optic birefringence vertical-cavity surface-emitting laser polarized elec- troluminescence
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煤矿机电设备技术故障及对策 被引量:3
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作者 杨建伟 《机械管理开发》 2017年第6期171-172,共2页
从机电设备在煤矿企业中重要性角度出发,针对煤矿机电设备故障,阐述了煤矿机电设备的技术故障诊断方式,并分析了煤矿机电设备技术故障解决对策。只有降低煤矿机电设备技术故障发生的概率,才能提高生产效率和保证生产安全。
关键词 故障与对策 机电设备 煤矿
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Following Electricity Price cut,Enterprises are Still Trapped in Dilemma
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《China Nonferrous Metals Monthly》 2015年第7期1-3,共3页
The executive meeting of the State Council made the decision on April 8 to reduce price of coal-fired power generation grid-entry electricity and prices of industrial and commercial use electricity,wherein,nationwide ... The executive meeting of the State Council made the decision on April 8 to reduce price of coal-fired power generation grid-entry electricity and prices of industrial and commercial use electricity,wherein,nationwide coal-fired power generation gridentry electricity price is reduced by about 0. 展开更多
关键词 electricity EXECUTIVE NATIONWIDE STILL PRICES elec
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SMS在电子政务中的应用 被引量:1
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作者 尤永涛 《鞍山师范学院学报》 2004年第4期56-58,共3页
提出了将SMS应用于电子政务系统的一种方案 ,可以实现点到多点的会议通知、信息播报等功能 ,解决了传统电子政务系统中此类功能实时性不足、不够方便等问题 .同时引入了对重要信息的重发控制机制 ,保证了在GSM网络时延较大、短消息丢失... 提出了将SMS应用于电子政务系统的一种方案 ,可以实现点到多点的会议通知、信息播报等功能 ,解决了传统电子政务系统中此类功能实时性不足、不够方便等问题 .同时引入了对重要信息的重发控制机制 ,保证了在GSM网络时延较大、短消息丢失或者用户关机等情况下 。 展开更多
关键词 SMS 电子政务 SMSS 数据库
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南昌市一起肠侵袭性大肠杆菌(EIEC)致感染性腹泻病爆发的临床与实验室研究 被引量:1
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作者 陈海婴 邹国和 范义兵 《现代诊断与治疗》 CAS 1999年第B12期83-84,共2页
关键词 肠侵袭性 大肠杆菌 腹泻 elec
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薄壁管类零件数控弯管加工技术研究
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作者 陈睿 《科教导刊(电子版)》 2018年第21期266-266,275,共2页
本文通过我公司实际生产中使用VB25 ELEC单层模的实际加工情况进行探索研究,简单介绍数控弯管数据描述输入,分析管路形状特点,阐述工装设计要求,通过某型号航空发动机管件进行实例验证。
关键词 薄壁 管件 VB25 elec 数控弯管
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5个改变太阳能利用的技术
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作者 海洋 《英语自学》 2008年第11期20-24,共5页
1.后接点的硅光电电池板提到太阳能技术,没有人比(美国)能源部更有能力清楚地将真正的潜能和厂家的虚假宣传区分开来。能源部是全国太阳能研究的先锋部队。所以,能源部选择将9月份刚刚发布的全新的 205
关键词 太阳能利用 后接点 虚假宣传 华盛顿特区 CIGS RACING 太阳能公司 plenty elec
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Henan's Aluminum Industry Basked In Warm Breeze of Policy
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《China Nonferrous Metals Monthly》 2014年第5期1-3,共3页
Recently,the National Development and Reform Commission and the Ministry of Industry and Information Technology announced that in order to better bring out the positive role of price lever in diffusing
关键词 HENAN elecTRICITY lever considerably SHANDONG elec
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电子媒介言语痕迹的侦查解读
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作者 袁瑛 周洲 《贵州警官职业学院学报》 2014年第6期97-101,共5页
网络,为人们带来方便快捷的同时,也为犯罪分子提供了实施违法犯罪的平台、载体和工具。随着信息技术的飞速发展,传统的"痕迹"已经远远不能满足侦查破案。随着犯罪手段的信息化、专业化、流窜化和智能化的加剧,"动态的电... 网络,为人们带来方便快捷的同时,也为犯罪分子提供了实施违法犯罪的平台、载体和工具。随着信息技术的飞速发展,传统的"痕迹"已经远远不能满足侦查破案。随着犯罪手段的信息化、专业化、流窜化和智能化的加剧,"动态的电子痕迹"的作用将凸显出来。如何从电子媒介言语轨迹中捕捉相关犯罪痕迹,这将为侦查破案开拓新路径。 展开更多
关键词 电子言语 电子痕迹 侦查解读
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采用改进层次分析法综合评估 500 kV 输电线路防雷改造效果 被引量:73
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作者 段若晨 王丰华 +3 位作者 顾承昱 满玉岩 傅正财 刘亚东 《高电压技术》 EI CAS CSCD 北大核心 2014年第1期131-137,共7页
为提高输电线路的防雷性能,提出了基于改进层次分析法(IAHP)和模糊综合评估法(FECM)的500 kV输电线路防雷改造评估方案。根据"初选—优选—验证"的评估流程,对几种典型防雷改造措施进行经济技术性分析,验证其有效性并得到备... 为提高输电线路的防雷性能,提出了基于改进层次分析法(IAHP)和模糊综合评估法(FECM)的500 kV输电线路防雷改造评估方案。根据"初选—优选—验证"的评估流程,对几种典型防雷改造措施进行经济技术性分析,验证其有效性并得到备选方案。根据目标与准则之间的关系,采用改进层次分析法计算各措施相对于目标的权重值。在此基础上,采用模糊综合评估法对各个方案进行评估计算,由评价因素矩阵得出相应隶属度,从而确定各防雷措施的评价等级。结果表明,采用改进层次分析法能够较为快速、准确地得到各防雷改造措施的评估权重值,进而利用模糊综合评估法划分其隶属等级,可直接查看防雷改造效果的优劣。对某500 kV输电线路进行了防雷改造效果评估,结果与实际统计数据基本相符。 展开更多
关键词 500 KV输电线路 防雷措施 技术经济有效性 电气几何模型 改进层次分析法 模糊综合评价 防雷效果评估
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(一)表没食子儿茶素没食子酸酯对活性氧自由基的清除作用机制 被引量:53
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作者 杨贤强 沈生荣 +2 位作者 候京武 赵保路 忻文娟 《中国药理学报》 CSCD 1994年第4期350-353,共4页
本文研究了(一)表没食子儿茶素没食子 酸酯[(—)-EGCG]清除O_(?)和·OH的半数清除率SC_(50)、清除速率常数k和清除反应的化学计量因子n,用体外模型分析了药物对活性氧自由基的清除机制和(—)-EGCG自由基的启动及结构特点,推论药物... 本文研究了(一)表没食子儿茶素没食子 酸酯[(—)-EGCG]清除O_(?)和·OH的半数清除率SC_(50)、清除速率常数k和清除反应的化学计量因子n,用体外模型分析了药物对活性氧自由基的清除机制和(—)-EGCG自由基的启动及结构特点,推论药物的清除反应中心为B、D和A环,每分子药物可捕捉6个O_(?)或·OH,与化学计量因子n=6相符。 展开更多
关键词 没食子酸酯 儿茶素 自由基
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电导法鉴定黄瓜抗寒性的研究 被引量:41
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作者 刘建辉 崔鸿文 《西北农业大学学报》 CSCD 1995年第4期74-77,共4页
用抗寒性不同的黄瓜品种,在子叶期和三片真叶期,研究了不同低温胁迫、低温胁迫不同时间以及不同渗透时间对叶片电解质渗出率的影响。结果表明:子叶期幼苗在一3℃低温下处理 18 h、渗透 90 min,是用电导法鉴定黄瓜品种抗寒... 用抗寒性不同的黄瓜品种,在子叶期和三片真叶期,研究了不同低温胁迫、低温胁迫不同时间以及不同渗透时间对叶片电解质渗出率的影响。结果表明:子叶期幼苗在一3℃低温下处理 18 h、渗透 90 min,是用电导法鉴定黄瓜品种抗寒性的适宜条件,三片真叶期与子叶期的鉴定结果一致。 展开更多
关键词 黄瓜 抗寒性 鉴定 低温胁迫 电解质渗出率 育种
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基于多维细粒度行为数据的居民用户画像方法研究 被引量:38
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作者 徐涛 黄莉 +1 位作者 李敏蕾 朱明杰 《电力需求侧管理》 2019年第3期47-52,58,共7页
以电网供需互动为目标,基于非入户终端的细粒度用电行为量测数据及营销系统的网络行为统计数据,开展居民用户画像方法研究。从用户行为、用电特性、消费习惯三大维度建立用户多源特征标签体系,并提出各个特征标签的萃取方法;基于欧式距... 以电网供需互动为目标,基于非入户终端的细粒度用电行为量测数据及营销系统的网络行为统计数据,开展居民用户画像方法研究。从用户行为、用电特性、消费习惯三大维度建立用户多源特征标签体系,并提出各个特征标签的萃取方法;基于欧式距离和曼哈顿距离提出改进K均值聚类算法,并应用此方法进行电力客户总体调控簇别分析,作为互动目标用户精准定位的依据;应用特征标签体系及总体调控簇别的划分结果,对居民用户进行综合画像及可视化呈现。最后以苏州金鸡湖示范区的1500户居民用户进行画像及应用效果分析。 展开更多
关键词 细粒度 特征标签 用户行为 用电特性 消费习惯 密度聚类 用户画像
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风力发电机状态监测与故障诊断技术综述 被引量:38
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作者 赵勇 韩斌 房刚利 《热力发电》 CAS 北大核心 2016年第10期1-5,共5页
本文阐述了风力发电机常见运行故障监测与诊断技术现状,并分别介绍风力发电机故障仿真及实验模拟方法、故障模拟实验平台、风力发电机状态监测系统,对风力发电机状态监测及故障诊断技术发展方向进行了展望。研究表明,基于多参量(如电信... 本文阐述了风力发电机常见运行故障监测与诊断技术现状,并分别介绍风力发电机故障仿真及实验模拟方法、故障模拟实验平台、风力发电机状态监测系统,对风力发电机状态监测及故障诊断技术发展方向进行了展望。研究表明,基于多参量(如电信号、振动信号、功率信号等)的故障监测诊断技术将成为风力发电机组状态监测与故障诊断领域未来发展的方向之一。 展开更多
关键词 风力发电 发电机 状态监测 故障诊断 机械故障 电气故障 振动故障
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