检索结果-南通市图书馆

Research on active disturbance rejection control method for turbine blade tip clearance

Science China(Technological Sciences) 2019年第10期62卷 1795-1804页

作者： WANG WeiMin Shao Xing LI QiHang Gao JinJi hao zerui Beijing Key Laboratory of Health Monitoring and Self-Recovery for High-End Mechanical Equipment Beijing University of ChemicalTechnologyBeijing100029China Department of Mechanical Engineering Tsinghua UniversityBeijing100084China

Blade tip clearance(BTC) is one of the key factors affecting the efficiency and reliability of high performance turbomachinery such as heavy duty steam turbines, aircraft engines and other gas turbo machines. The self-adjusting ability of BTC according to the operation condition changing is important to meet the requirement of performance. In this paper, the principle and method of adjusting the BTC by controlling the axial displacement of the rotor were proposed and studied. The basic principle is that the BTC of the turbomachinery with a conical tail shroud will be affected by the axial displacement of rotor and thereby can be adjusted by controlling the axial position of rotor, which can be adjusted by the controllable oil pressure acting on the thrust bearing. To reach a higher control precision, lower noise and model perturbation, an adaptive quasi-sliding mode control(AQSMC) algorithm based on the disturbance observer(DOB) was designed, and numerical and experimental investigations were carried out. The numerical simulation results show that this algorithm can not only effectively suppress the disturbance, but also, compared with the general reaching law, effectively reduce the chattering and transient high gain switching effect of the closed-loop controller system and avoid the instability caused by the controller. Based on the DOB-AQSMC algorithm, the BTC was stabilized within 2 s with no overshoot and no misalignment in the test rig, and this algorithm achieves a better control performance than the proportion-integral-differential(PID) algorithm. These achievements can be used to push forward the intelligent turbomachinery development.

关键词： blade tip clearance turbomachinery active disturbance rejection control DOB-AQSM method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

戒烟联合氟替美维对稳定期慢性阻塞性肺疾病合并呼吸衰竭患者的改善效果

引用

中国临床研究 2023年第6期36卷 867-871页

作者：李书阅董亮亮童春堂郝泽蕊冯淬灵聊城市第二人民医院呼吸内科山东聊城252600 北京大学人民医院中医科北京100000

目的对稳定期慢性阻塞性肺疾病(COPD)合并呼吸衰竭患者采用戒烟联合氟替美维,分析对其肺功能、运动功能的改善效果。方法通过便利抽样、对照原则回顾性研究2020年1月至2022年1月聊城市第二人民医院接诊的100例稳定期COPD合并呼吸衰竭患... 详细信息

目的对稳定期慢性阻塞性肺疾病(COPD)合并呼吸衰竭患者采用戒烟联合氟替美维,分析对其肺功能、运动功能的改善效果。方法通过便利抽样、对照原则回顾性研究2020年1月至2022年1月聊城市第二人民医院接诊的100例稳定期COPD合并呼吸衰竭患者,给予氟替美维治疗的为对照组(n=50),给予戒烟联合氟替美维治疗的为观察组(n=50),比较两组临床疗效、肺功能指标、6分钟步行试验(6WMT)、呼吸困难评分(mMRC)、血清炎症指标。结果观察组临床总有效率(94.00%)高于对照组(72.00%)(P<0.01),治疗后,观察组用力肺活量(FVC)、第1秒用力呼气容积(FEV_(1))、FEV_(1)/FVC均高于对照组(P<0.05),6WMT高于对照组(P<0.05),mMRC评分低于对照组(P<0.05),血清肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-8、IL-6均低于对照组(P<0.05)。结论戒烟联合氟替美维可有效改善稳定期COPD合并呼吸衰竭患者肺功能、运动功能,减轻呼吸困难程度与机体炎症反应。

关键词：戒烟氟替美维慢性阻塞性肺疾病,稳定期呼吸衰竭肺功能运动功能炎症反应

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical Study on the Effect of Vortex Generators on the Aerodynamic Drag of a High-Speed Train

引用

Fluid Dynamics & Materials Processing 2024年第2期20卷 463-473页

作者： Tian Li hao Liang zerui Xiang Jiye Zhang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu610031China School of Design Southwest Jiaotong UniversityChengdu610031China

A relatively high aerodynamic drag is an important factor that hinders the further acceleration of high-speed *** the shear stress transport(SST)k-ωturbulence model,the effect of various vortex generator types on the aerodynamic characteristics of an ICE2(Inter-city Electricity)train has been *** results indi-cate that the vortex generators with wider triangle,trapezoid,and micro-ramp arranged on the surface of the tail car can signiﬁcantly change the distribution of surface pressure and affect the vorticity intensity in the *** alteration effectively reduces the resistance of the tail ***,the micro-ramp vortex generator with its convergent structure at the rear exhibits enhancedﬂow-guiding capabilities,resulting in a 15.4%reduction in the drag of the tail car.

关键词： Vortex generator aerodynamic drag reduction numerical simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Janus Quasi‑Solid Electrolyte Membranes with Asymmetric Porous Structure for High‑Performance Lithium‑Metal Batteries

引用

Nano-Micro Letters 2024年第6期16卷 221-232页

作者： zerui Chen Wei Zhao Qian Liu Yifei Xu Qinghe Wang Jinmin Lin hao Bin Wu Institute for Composites Science Innovation(InCSI)and State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China

Quasi-solid electrolytes(QSEs)based on nanoporous materials are promising candidates to construct high-performance Limetal batteries(LMBs).However,simultaneously boosting the ionic conductivity(σ)and lithium-ion transference number(t^(+)) of liquid electrolyte confined in porous matrix remains ***,we report a novel Janus MOFLi/MSLi QSEs with asymmetric porous structure to inherit the benefits of both mesoporous and microporous *** Janus QSE composed of mesoporous silica and microporous MOF exhibits a neat Li^(+) conductivity of 1.5.10^(–4)S cm^(−1) with t^(+) of 0.71.A partially de-solvated structure and preference distribution of Li^(+)near the Lewis base O atoms were depicted by MD ***,the nanoporous structure enabled efficient ion flux regulation,promoting the homogenous deposition of Li^(+).When incorporated in Li||Cu cells,the MOFLi/MSLi QSEs demonstrated a high Coulombic efficiency of 98.1%,surpassing that of liquid electrolytes(96.3%).Additionally,NCM 622||Li batteries equipped with MOFLi/MSLi QSEs exhibited promising rate performance and could operate stably for over 200 cycles at 1 *** results highlight the potential of Janus MOFLi/MSLi QSEs as promising candidates for next-generation LMBs.

关键词： Metal-organic frameworks Mesoporous silicas Quasi-solid electrolytes Janus structure Lithium-metal battery

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Solvent sieving separators implement dual electrolyte for highvoltage lithium-metal batteries

引用

Nano Research 2023年第4期16卷 4901-4907页

作者： Yan Liu Qianqian Liu Youran Hong Yifei Xu zerui Chen Wei Zhao Zhikun Hu Jiangwei Wang hao Bin Wu School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China

Lithium-metal batteries(LMBs)based on high-voltage cathodes would deliver high specific energy density to meet the demand of future energy ***,developing liquid electrolytes with wide electrochemical window for high-energy LMBs is intrinsically ***,we demonstrate metal-organic framework-functionalized separators(PE@MOF)with solvent sieving capability that implement dual electrolyte for *** capability of PE@MOF separator to block the diffusion of liquid electrolytes has been *** PE@MOF separator notably suppresses solvents shuttling,enabling the independent optimization of cathode-electrolyte and anode-electrolyte *** adapting commercial carbonate and ether electrolytes on cathode and anode sides,respectively,robust cathode-electrolyte interphase(CEI)and solid electrolyte interface(SEI)have been built on both *** lifespan of LiCoO_(2)(LCO)|Li full cell has been notably extended when using dual electrolyte and the solvent-sieving PE@MOF *** work demonstrates a new strategy to separately optimize the local environments at electrodes and to develop high-energy LMBs using low-cost and commercially available electrolytes.

关键词： dual electrolyte metal-organic framework lithium metal battery

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Morphology evolution and breakdown mechanism of cross-linked polyethylene(XLPE)-silicone rubber(SiR)interface induced by silicone grease diffusion

引用

High Voltage 2022年第4期7卷 802-811页

作者： zerui Li Kai Zhou Pengfei Meng hao Yuan Zikang Wang Yidong Chen Yuan Li Guangya Zhu College of Electrical Engineering Sichuan UniversityChengduSichuanChina

Silicone grease(SG)is used for lubrication during cable accessory installation and can penetrate into the silicone rubber(SiR),leading to properties deterioration of the *** this study,the effects of SG on the breakdown characteristics of the cross-linked poly-ethylene(XLPE)-SiR interface are ***,the variation of the XLPE-SiR interface breakdown voltage with SG coating time is experimentally *** interface breakdown voltage significantly increases after SG is applied,remains stable for coating times of up to approximately 144 h and then rapidly decreases;the minimum interface breakdown voltage is lower than that without the SG ***,the effects of SG on the chemical composition and surface topography of the SiR are examined by infrared spectroscopy and optical profilometry,*** SG penetration does not change the functional groups of the SiR but significantly increases its surface ***,the interface electric-field distribution after coating with SG is analysed by finite-element simulation,revealing that the residual SG at the interface distorts the interface electric field after a long coating *** increase in the SiR surface roughness caused by SG diffusion and the interface electric-field distortion caused by the residual SG together lead to the decrease of the interface breakdown voltage.

关键词： coating interface diffusion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

新辅助免疫治疗及联合化疗在NSCLC中的研究进展

引用

中国肺癌杂志 2021年第4期24卷 284-292页

作者：陈思赵泽锐龙浩中山大学肿瘤防治中心胸外科广州510060

非小细胞肺癌(non-small cell lung cancer,NSCLC)患者在接受标准治疗后仍有较高的复发、转移风险。免疫检查点抑制剂治疗在晚期肺癌患者中获得巨大进展,临床前研究及部分II期临床研究为新辅助免疫治疗局部晚期NSCLC提供理论支持和临床... 详细信息

非小细胞肺癌(non-small cell lung cancer,NSCLC)患者在接受标准治疗后仍有较高的复发、转移风险。免疫检查点抑制剂治疗在晚期肺癌患者中获得巨大进展,临床前研究及部分II期临床研究为新辅助免疫治疗局部晚期NSCLC提供理论支持和临床证据。本篇综述阐述了免疫治疗的机制及新辅助治疗的理论优势,总结现已发表前期数据和中期分析的多篇临床研究,分析了新辅助免疫单药治疗对比免疫联合化疗的病理缓解率和安全性。NCT02259621、NEOSTAR、LCMC3及ChiCTR-OIC-17013726分别报告了新辅助应用纳武利尤单抗、阿替利珠单抗和信迪利单抗单药的有效性和安全性,同时NEOSTAR双药免疫组的数据显示双药免疫相较于单药可以获得更高的病理缓解率,双药免疫的高不良反应发生率也引起研究者的担忧。NCT02716038、SAKK 16/14和NADIM研究的数据提示新辅助免疫联合化疗的病理缓解率高于新辅助单药免疫抑制剂治疗,且不良反应可耐受。本文进一步阐述了化疗联合免疫抑制剂治疗的作用机制,并就新辅助免疫治疗后的疗效评估进行讨论。

关键词：肺肿瘤免疫治疗新辅助综述

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Lattice-mismatch-induced formation of defect-rich Pd–Cu alloy nanocages for enhanced formic acid oxidation activity

引用

Science China Chemistry 2024年

作者： Zhaojun Liu Zhengyan Wang Zhaoyu Wang hao Yuan Yuke Bai Xiaoxiao Wang zerui Mu Chunxia Wu Kai Liu Zhun Hu Chuanbo Gao Sate Key Laboratory of Multiphase Flow in Power Engineering Frontier Institute of Science and Technology Xi'an Jiaotong University Institute of Industrial Catalysis School of Chemical Engineering and Technology Xi'an Jiaotong University

Crystallographic defects in noble metal nanocrystals are recognized as highly active catalytic sites, significantly enhancing activities in many important reactions. Despite their importance, synthesizing noble metal nanocrystals with a high density of defects poses a considerable synthetic challenge. Here, we present a novel lattice mismatch-induced formation mechanism to create high-density defects in noble metal nanocrystals. This approach takes advantage of lattice mismatch to enable nonepitaxial nucleation and growth of a noble metal on a foreign metal substrate, forming abundant noble metal crystallites with random lattice orientations not dictated by the substrate lattice. As these crystallites grow extensively, they merge, forming numerous grain boundaries and yielding defect-rich noble metal nanocrystals. Defect-rich alloy nanocrystals can also be synthesized through a subsequent vacancy-diffusion alloying process. We take defective PdCu alloy nanocages as an example and demonstrate the effectiveness of crystallographic defects in enhancing catalytic performance of noble metal *** nanocages exhibit superior activity in the electrocatalytic formic acid oxidation reaction, which is 1.6 times greater than their defect-free counterparts. Our strategy offers a new avenue for creating defect-rich noble metal nanocrystals as highly efficient catalysts for a wide array of catalytic applications.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

基于路网拓扑的尾气遥测设备的布点策略

引用

大气与环境光学学报 2020年第5期15卷 365-371页

作者：李泽瑞康宇谢皓中国科学技术大学信息科学技术学院自动化系安徽合肥230027 合肥综合性国家科学中心人工智能研究院安徽合肥230088 中国科学技术大学火灾科学国家重点实验室安徽合肥230027 中国科学技术大学先进技术研究院安徽合肥230088 中国科学院合肥物质科学研究院安徽光学精密机械研究所中国科学院环境光学与技术重点实验室安徽合肥230031 中国科学技术大学安徽合肥230027

建设城市路网机动车尾气遥测系统可实现对城市区域在路车辆尾气排放状况的全面监控,而在遥测系统中,尾气遥测设备在路网中的布设位置直接影响设备的监测效果,因此设备的布点选址问题是遥测系统构建的关键之一。针对该问题,提出基于路网... 详细信息

建设城市路网机动车尾气遥测系统可实现对城市区域在路车辆尾气排放状况的全面监控,而在遥测系统中,尾气遥测设备在路网中的布设位置直接影响设备的监测效果,因此设备的布点选址问题是遥测系统构建的关键之一。针对该问题,提出基于路网拓扑的遥测设备布点策略。在该方法中,首先建立了这一问题的数学模型,并借助交通路网图线图的可达矩阵来描述路段之间的连接程度,进而使用基于二重结构编码的遗传算法来求解模型。实验研究结果表明,相对于传统的布点方案,本文所提出的布点策略可截获更多数量的个体车辆。

关键词：尾气遥测设备布点路网拓扑遗传算法

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

安徽某铁矿酸性矿山废水夏季和秋季微生物群落结构特征

引用

环境科学学报 2016年第7期36卷 2397-2407页

作者：裴理鑫鲁青原郝春博杜泽瑞鲁艳春张帆中国地质大学(北京) 水资源与环境学院北京100083 中国市政工程东北设计研究总院有限公司长春130021

分别采集了夏秋两季安徽某铁矿的酸性矿山废水样品,分析其物理化学参数,并利用分子生物学方法研究了该酸性矿山废水中微生物群落结构随时间和空间的变化规律.结果表明:该矿山废水酸性极强,夏季所采样品pH在2.80左右,且阴阳离子含量很高,... 详细信息

分别采集了夏秋两季安徽某铁矿的酸性矿山废水样品,分析其物理化学参数,并利用分子生物学方法研究了该酸性矿山废水中微生物群落结构随时间和空间的变化规律.结果表明:该矿山废水酸性极强,夏季所采样品pH在2.80左右,且阴阳离子含量很高,Al^(3+)为1108~1138mg·L^(-1),SO_4^(2-)则高达19.80~23.79 g·L^(-1).秋季样品p H没有明显变化,但由于两次采样期间的大量降水,样品中各离子含量明显低于夏季.值得注意的是,该极端酸性的矿山废水中叶绿素a含量较高,夏季达63.8~94.2μg·L^(-1),秋季则降至16.6~32.7μg·L^(-1).无论是在夏季还是秋季,Alphaproteobacteria在绝大多数位点的细菌群落中占据着优势地位.化能异养菌Acidiphilium是最主要的细菌菌属,它在夏季和秋季各位点群落中所占比例都达20%左右,这应该与其丰富的代谢方式有关.对于真核微生物群落,夏季主要为尖毛虫和小球藻,秋季主要为棕鞭藻和小球藻.小球藻是该酸性生态系统主要的生产者,尖毛虫和棕鞭藻则扮演着顶级消费者的角色.该酸性废水应处于酸水形成末期,所以细菌群落中化能异养菌占据着优势地位,化能自养菌比例较少.由于温度等理化性质的不同,微生物群落结构随时间和空间发生了一定变化,其中以真核微生物群落结构变化最为显著.

关键词：酸性矿山废水嗜酸微生物群落结构多样性

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：