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高压直流接触器磁吹系统的优化设计

电器与能效管理技术 2024年第1期 43-46页

作者：蔡明马伟王建雄贵州振华群英电器有限公司贵州贵阳550018

在高压直流接触器的磁吹灭弧系统中,当电弧燃烧时常采用永磁体拉长电弧致其熄灭,而熄弧时间又直接影响到产品的寿命次数。研究表明永磁体磁感应强度越强,熄弧时间越短,但触点中心磁感应强度与永磁体的几何中心磁感应强度有直接关系。通... 详细信息

在高压直流接触器的磁吹灭弧系统中,当电弧燃烧时常采用永磁体拉长电弧致其熄灭,而熄弧时间又直接影响到产品的寿命次数。研究表明永磁体磁感应强度越强,熄弧时间越短,但触点中心磁感应强度与永磁体的几何中心磁感应强度有直接关系。通过仿真优化常用磁吹灭弧系统结构形式,减小单个永磁体几何中心磁感应强度,提高磁吹灭弧系统空间磁感应强度,以提升高压直流接触器产品的生产效率及寿命次数。

关键词：高压直流接触器磁吹灭弧磁感应强度

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基于PVDF的三维指尖力传感器设计

传感器与微系统 2019年第6期38卷 96-98,101页

作者：魏健雄万舟单阳祝奔奔昆明理工大学信息工程与自动化学院云南昆明650504

在智能机械手控制过程中,为了获取指尖力三维信息,设计了一种基于聚偏二氟乙烯(PVDF)压电薄膜的指尖力触觉传感器,并通过数学模型描述了压电薄膜及传感探头原理,设计了相应的调理电路。以和接触面所呈不同角度的指尖力为测试对象。测试... 详细信息

在智能机械手控制过程中,为了获取指尖力三维信息,设计了一种基于聚偏二氟乙烯(PVDF)压电薄膜的指尖力触觉传感器,并通过数学模型描述了压电薄膜及传感探头原理,设计了相应的调理电路。以和接触面所呈不同角度的指尖力为测试对象。测试结果显示:所设计的指尖力传感器能准确检测指尖力的三维信息,可用于实际的指尖力检测。

关键词：指尖力三维聚偏二氟乙烯触觉传感器

驱动压指导PEEP滴定用于术中机械通气的meta分析

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重庆医学 2024年第5期53卷 760-765页

作者：周建雄刘春雨魏闯重庆大学附属肿瘤医院麻醉科重庆400030

目的系统评价驱动压指导固定呼气末正压(PEEP)滴定用于术中机械通气的有效性与安全性。方法计算机检索PubMed、Web of Science、the Cochrane Library、Embase、中国知网(CNKI)、万方和维普数据库,检索驱动压指导PEEP滴定用于术中机... 详细信息

目的系统评价驱动压指导固定呼气末正压(PEEP)滴定用于术中机械通气的有效性与安全性。方法计算机检索PubMed、Web of Science、the Cochrane Library、Embase、中国知网(CNKI)、万方和维普数据库,检索驱动压指导PEEP滴定用于术中机械通气的随机对照研究(RCT),检索时间为建库至2023年11月8日。由2名研究者独立筛选文献、提取资料并评价纳入研究的偏倚风险后,采用RevMan 5.4软件进行meta分析。结果共纳入19篇文献,共计患者2 906例,研究组采用驱动压指导PEEP滴定的肺保护通气策略,共计患者1 440例,对照组采用传统肺保护通气策略,共计患者1 466例。与对照组比较,研究组在非胸科手术中术后肺部并发症(PPCs)发生率更低(RR=0.53,95%CI:0.43~0.65,P<0.001),而在胸科手术中差异无统计学意义(RR=0.89,95%CI:0.78~1.02,P=0.09)。与对照组比较,研究组术中肺顺应性升高(MD=6.90 L/cmH_(2)O,95%CI:5.80~7.99,P<0.001),住院时间缩短(MD=-0.27 d, 95%CI:-0.43~-0.12,P<0.001),而术中平均动脉压(MAP)差异无统计学意义(MD=0.36 mmHg, 95%CI:-1.30~2.01,P=0.67)。结论与传统肺保护通气比较,驱动压指导PEEP滴定通气能够提高患者术中肺顺应性,降低非胸科手术PPCs发生率,缩短住院时间,且不增加血流动力学紊乱的风险。

关键词：驱动压肺保护性通气术后肺部并发症 meta分析

An Experimental Investigation on Low Load Combustion Stability and Cold-Firing Capacity of a Gasoline Compression Ignition Engine

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Engineering 2019年第3期5卷 558-567页

作者： Lei Zhou jianxiong Hua Haiqiao wei Yiyong Han State Key Laboratory of Engines Tianjin University Tianjin 300072 China Guangxi Yuchai Machinery Co. Ltd. Yulin 537005 China

Gasoline compression ignition (GCI) is one of the most promising combustion concepts to maintain low pollutant emissions and high efficiency. However, low load combustion stability and firing in cold-start operations are two major challenges for GCI combustion. Strategies including negative valve overlap (NVO), advanced injection strategies, fuel reforming, and intake preheating have been proposed in order to solve these difficulties;however, the cold start is still an obstacle. The objective of this work is to study effective methods to achieve GCI engine cold start-up. This work combines NVO, in-cylinder fuel reforming, and intake preheating to achieve quick firing under cold-start conditions and the subsequent warmup conditions. The results show that start of injection (SOI) during the intake stroke yields the best fuel economy, and injection during the compression stroke has the potential to extend the low load limit. Furthermore, SOI during the NVO period grants the ability to operate under engine conditions with cold intake air and coolant. With highly reactive products made by in-cylinder fuel reforming and fast heat accumulation in the combustion chamber, the NVO injection strategy is highly appropriate for GCI firing. An additional assisted technical method, such as intake preheating, is required to ignite the first firing cycle for a cold-start process. With the combination of NVO, in-cylinder fuel reforming, and intake preheating, the GCI engine successfully started within five combustion cycles in the experiment. After the firing process, the engine could stably operate without further intake preheating;thus, this method is appropriate for engine cold-start and warm-up.

关键词： Gasoline compression ignition Cold start Warm-up condition Fuel-injection strategy Combustion stability

直流接触器触头倒角及中心磁感应强度对电寿命的影响

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电器与能效管理技术 2024年第4期 53-56页

作者：蔡明马伟王建雄李超贵州振华群英电器有限公司贵州贵阳550018

密封直流接触器开断负载时,灭弧室内触头喷溅不可避免。通过分组试验的方法来验证触头倒角及中心磁感应强度对电寿命的影响。结果表明,增大触头中心磁感应强度,总开断负载的次数会增加,喷溅也会增多,从而导致介质耐电压和绝缘电阻降低;... 详细信息

密封直流接触器开断负载时,灭弧室内触头喷溅不可避免。通过分组试验的方法来验证触头倒角及中心磁感应强度对电寿命的影响。结果表明,增大触头中心磁感应强度,总开断负载的次数会增加,喷溅也会增多,从而导致介质耐电压和绝缘电阻降低;增大触头倒角,喷溅会减少,介质耐电压和绝缘电阻会提高,但总开断负载的次数会减少。

关键词：直流接触器直流开断磁吹灭弧电寿命触头倒角

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参芪真武汤加味治疗原发性肾病综合征疗效及对患者肾功能、微炎状态、凝血纤溶功能的影响

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陕西中医 2024年第8期45卷 1052-1055,1060页

作者：任剑雄韦淇元梁建亮佛山市中医院广东佛山528000

目的:探讨参芪真武汤加味治疗原发性肾病综合征效果及对患者肾功能、微炎状态、凝血纤溶功能的影响。方法:选取脾肾阳虚证原发性肾病综合征患者110例,根据治疗方案分为两组,观察组和对照组各55例。对照组给予常规对症治疗,观察组在对照... 详细信息

目的:探讨参芪真武汤加味治疗原发性肾病综合征效果及对患者肾功能、微炎状态、凝血纤溶功能的影响。方法:选取脾肾阳虚证原发性肾病综合征患者110例,根据治疗方案分为两组,观察组和对照组各55例。对照组给予常规对症治疗,观察组在对照组基础上给予参芪真武汤加味治疗,两组均连续治疗8周。比较两组治疗总有效率及不良反应发生情况,同时观察治疗前后中医证候积分、肾功能[24 h尿蛋白定量(24 hTP)、血白蛋白(ALB)、尿素氮(BUN)、血清肌酐(Cr)]、微炎状态[高敏-C反应蛋白(hs-CRP)、白细胞介素-21(IL-21)、白细胞介素-13(IL-13)]、凝血纤溶功能[纤维蛋白原(FIB)、D-二聚体(D-D)]变化情况。结果:观察组临床总有效率为90.91%,高于对照组的76.36%(P0.05)。结论:参芪真武汤加味治疗原发性肾病综合征脾肾阳虚证可提高临床效果,降低中医证候积分,促进肾功能和凝血纤溶功能改善,减轻机体微炎症状态,且安全性佳。

关键词：原发性肾病综合征参芪真武汤脾肾阳虚证肾功能微炎症状态凝血纤溶功能

Synergistic modulation of Li nucleation/growth enabled by CNTswrapped lithiophilic CoP/Co_(2)P decorated hollow carbon polyhedron host for stable lithium metal anodes

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Nano Research 2023年第4期16卷 4961-4969页

作者： Zhicui Song Yuchi Liu Zihao Wang jianxiong Xing Chaohui wei wei Zou Aijun Zhou Jingze Li School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Research and Development Center Tianqi Lithium Co.Ltd.Chengdu 610093China Lithium Resources and Lithium Materials Key Laboratory of Sichuan Province Tianqi Lithium CorporationChengdu 610000China

Infinite volume expansion and uncontrolled lithium dendrite growth are the main bottlenecks that greatly hinder the commercial application of lithium metal ***,derived from zeolitic imidazolate framework(ZIF)-67,carbon nanotubes(CNTs)-wrapped and CoP/Co_(2)P uniformly distributed nitrogen-doped hollow porous polyhedron carbon(CNT-CoP@NC)is elaborately designed as lithium metal host.A hybrid of N-doping and metallic phosphides modifications improves the lithiophilicity and reduces the nucleation barrier,consequently leading to homogeneous nucleation and smooth deposition of metallic lithium,thus suppresses the growth of Li ***,self-generated CNTs arrays efficiently reduce the local current ***,the reduced lithium is preferentially deposited into the hollow structure of CNT-CoP@NC and then filled the voids among the CNT-CoP@NC *** all-pervasive Li plating design can not only alleviate the volume effect,but also maximize the anode space *** from these synergistic modulations,even with an ultra-thin(7.2μm)anode layer of CNT-CoP@NC host,a high Coulombic efficiency for more than 400 cycles and an extended lifespan of 1,700 h under 1 mA·cm^(−2)can be *** paired with a competitive high mass loading(17.1 mg·cm^(−2))LiFePO4 cathode,a superb cycling stability(126.7 mAh·g^(−1)over 550 cycles)is recorded at 1 C.

关键词： lithium metal anodes metal organic framework hollow structure dendrite-free synergistic modulations

The theory and practice in the evolution of trusted computing

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Chinese Science Bulletin 2014年第32期59卷 4173-4189页

作者： Dengguo Feng Yu Qin wei Feng jianxiong Shao Trusted Computing and Information Assurance Laboratory Institute of Software Chinese Academy of Sciences State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences

Trusted computing(TC)is an emerging technology to enhance the security of various computing platforms by a dedicated secure chip(TPM/TCM),which is widely accepted by both the industrial and academic *** paper attempts to sketch the evolution of TC from the view of our theoretical and engineering *** theory,we focus on protocol design and security *** have proposed the first ECDAA protocol scheme based on q-SDH assumption,which highlights a new way to design direct anonymous attestation *** technical evolution,we discuss the key technologies of trust chain,trusted network connection and TC testing and *** break through several key technologies such as trusted boot,OS measurement and remote attestation,and implement a TC system from TPM/TCM to *** also design and implement a testing and evaluation system of TC platform,which is the first one put into practical application in ***,with the rapid development of cloud computing and mobile applications,TC is moving toward some new directions,such as the trust in cloud and mobile environments,new TPM standard,and flexible trust execution environment trust establishment method.

关键词：可信计算 TCM 计算平台移动应用 TPM 安全芯片安全分析匿名认证

陶然亭公园野生地被植物资源综合评价分析与应用研究

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绿色科技 2024年第13期26卷 8-13页

作者：徐小云于佳杨威李剑雄北京市陶然亭公园管理处北京100050

以陶然亭公园内七大景区的野生地被植物为研究对象,调查了野生地被植物的种类、生长势、观赏部位、适应力、株高等基本信息,并采用层次分析法(AHP)构建了野生地被植物资源评价体系。结果表明:陶然亭公园共有野生地被植物52种,隶属24科47... 详细信息

以陶然亭公园内七大景区的野生地被植物为研究对象,调查了野生地被植物的种类、生长势、观赏部位、适应力、株高等基本信息,并采用层次分析法(AHP)构建了野生地被植物资源评价体系。结果表明:陶然亭公园共有野生地被植物52种,隶属24科47属,其中多年生植物占比最高,达到44.23%;通过K-means聚类分析法,最终评选出Ⅰ级地被植物15种,Ⅱ级地被植物15种,Ⅲ级地被植物19种,Ⅳ级地被植物3种。该评价体系更强调野生地被植物的观赏性,与公园景观需求相符。

关键词：野生地被植物综合评价层次分析法园林应用