检索结果-南通市图书馆

润滑与密封 2014年第11期39卷 118-120页

作者：朱军赵飞虎刘龙全成都一通密封有限公司四川成都610100

对真空耙式干燥工艺及设备特点进行分析,以轴径为320 mm的某型号真空耙式干燥器为例,设计其密封结构,探讨其冲洗方案及摩擦副、辅助密封和结构件的选材。模拟实际工况对设计的样机进行的运转试验,结果表明该密封结构密封效果良好。

关键词：真空干燥器机械密封泄漏

Conformation and Counterion Distribution of Polyelectrolyte in Solution as Viewed from Dielectric Approach

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第9期42卷 1278-1301,I0005页

作者： Kong-Shuang zhao College of Chemistry Beijing Normal UniversityBeijing 100875China

Polyelectrolyte solutions are more variable than uncharged macromolecule due to electrical interaction between charged molecules and surrounding ***,the subject of polyelectrolyte solutions has attracted a wide range of interests in both basic and applied research,and has also been extensively ***,the understanding of the molecular dynamics and conformation of polyelectrolytes in solution remains to be deepened,and universal consensus on some key issues have not been *** methods have contributed to solving the above problems in different ways,including dielectric relaxation spectroscopy(DRS).In this perspective,we briefly reviewed the history of dielectric spectroscopic research on polyelectrolyte solution,with emphasis on summarizing our *** particular,we expound the characteristics of DRS and its ability to obtain the internal information of the system of ***,we evaluate the advantages and limitations of the dielectric method and discussed future prospects of this field.

关键词： Polyelectrolyte Dielectric relaxation spectroscopy Chain conformation Thermosensitive microgel PNIPAM microgel Spherical polyelectrolyte brushes

One dimensional CeO_(2) nanorods/poly(ethylene oxide) solid composite electrolyte for all-solid-state lithium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第3期42卷 570-577,I0005页

作者： Yudi Guo Erqing zhao Xiaofang zhao Shuailei Liu School of Chemistry and Materials Engineering Xinxiang UniversityXinxiang453003China School of Chemistry and Chemical Engineering Henan Institute of Science and TechnologyXinxiang453003China

The research of poly(ethylene oxide)(PEO)-based solid composite electrolyte with high ionic conductivity and excellent interfacial stability is the key to the development of all-solid-state lithium-ion batteries(ASSLIBs). Herein, uniform nanorod structured CeO_(2) fillers were controllably synthesized by electrospinning, which were subsequently filled into PEO polymer to prepare CeO_(2)/PEO solid composite electrolyte. The addition of CeO_(2) nanorods can reduce both the glass transition temperature and the melting point of PEO polymer, and also interact with PEO and lithium bis(trifluoromethanesulphonyl)imide(LITFSI) by Lewis acid—base reaction. Therefore, the solid composite electrolyte exhibits a high ionic conductivity of 4.52 × 10^(-4)S/cm, a wide electrochemical stability window of about 4.8 V, and a good interfacial stability with Li at 55℃. Moreover, the LiFePO_4/Li ASSLIB divulges the discharging specific capacity of 165, 162, 156 and 146 mA,h/g at 0.2, 0.5, 1 and 2 C, respectively, and achieves the capacity retention of 90.3% after 150 cycles at 0.5 C. Consequently, one dimensional CeO_(2) nanorods can be considered as an alternative filler for polymeric solid electrolyte.

关键词： Poly(ethylene oxide) Solid composite electrolyte CeO_(2)nanorods Ionic conductivity Rare earths

The trajectory of rice from wild to domesticated:A new chapter in the study of origins of agriculture

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第9期67卷 3011-3012页

作者： Zhijun zhao Institute of Cultural Heritage Shandong UniversityQingdao 266237China

Rice(Oryza sativa)is one of the most important food crops in the world today,feeding more than one-third of the global *** domestication of rice has always been an international research topic(Gross and zhao,2014).When,where,and how rice was cultivated and eventually domesticated has been a hot issue in many research fields such as archaeology,biology,and agronomy(Fuller et al.,2009).

关键词： sativa Oryza crops

(Pb,Sr)Nb_2O_6-NaNbO_3薄膜的制备与介电性能研究

在线全文

学校读者我要写书评

暂无评论

稀有金属 2017年第7期41卷 826-830页

作者：谭飞虎赵鸿滨于军洋张庆猛魏峰杜军北京有色金属研究总院先进电子材料研究所北京100088 北京有色金属研究总院智能传感功能材料国家重点实验室北京100088

采用脉冲激光技术(PLD)在p+-Si上沉积了(Pb,Sr)Nb2O6-Na Nb O3介质薄膜,介质薄膜在氧化气氛下进行不同温度的热处理,进行光刻图形化、磁控溅射沉积电极之后,形成Al/p+-Si/(Pb,Sr)Nb2O6-Na Nb O3/Au结构的MIM(金属-绝缘体-金属)电容器。... 详细信息

采用脉冲激光技术(PLD)在p+-Si上沉积了(Pb,Sr)Nb2O6-Na Nb O3介质薄膜,介质薄膜在氧化气氛下进行不同温度的热处理,进行光刻图形化、磁控溅射沉积电极之后,形成Al/p+-Si/(Pb,Sr)Nb2O6-Na Nb O3/Au结构的MIM(金属-绝缘体-金属)电容器。通过X射线衍射(XRD)、原子力显微镜(AFM)和高分辨透射电子显微镜(HRTEM)对介质薄膜的微观形貌及结构进行分析。通过测试不同温度热处理后薄膜电容器的I-V和C-V电学特性,研究了不同温度热处理对薄膜电容器漏电流密度、电容、介电损耗及物相的影响,并对电容器电容和损耗的偏压特性进行了分析,结果表明,800℃热处理能显著提高薄膜的介电常数并降低漏电流密度。在偏压为-1 V,频率为1 k Hz的测试环境下,其介电常数为33,漏电流密度约为4.104×10-9A·cm-2,满足微电子领域内对漏电流小于1×10-8A·cm-2的要求;对薄膜电容器特性曲线拟合后得到其二次项电压系数为188,符合国际半导体技术蓝图(ITRS)对未来MIM电容提出的要求,具有良好的应用前景,是制备无机薄膜电容器理想的介质材料。

关键词： (Pb,Sr)Nb2O6-NaNbO3薄膜脉冲激光沉积法微晶玻璃薄膜 MIM 介电性能

在线全文

学校读者我要写书评

暂无评论

深海水下装备水润滑轴承研究现状与进展

船舶工程 2019年第11期41卷 125-130,136页

作者：宋强范华涛王瑞赵飞虎中国船舶科学研究中心深海载人装备国家重点实验室

阐述了国内外水润滑轴承的技术现状与发展动态,介绍了国内外主要供应商的水润滑轴承产品的技术特点和独特优势,对比分析了不同水润滑轴承的性能参数,总结了水润滑轴承在选型时需要重点考虑的问题,重点介绍了水润滑轴承的关键技术,在此... 详细信息

阐述了国内外水润滑轴承的技术现状与发展动态,介绍了国内外主要供应商的水润滑轴承产品的技术特点和独特优势,对比分析了不同水润滑轴承的性能参数,总结了水润滑轴承在选型时需要重点考虑的问题,重点介绍了水润滑轴承的关键技术,在此基础上提出深海水润滑轴承设计流程,可为深海水下装备水润滑轴承的选型和设计提供参考。

关键词：深海潜水器水润滑轴承低噪声

A DIRECT DISCONTINUOUS GALERKIN METHOD FOR TIME FRACTIONAL DIFFUSION EQUATIONS WITH FRACTIONAL DYNAMIC BOUNDARY CONDITIONS

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2024年第1期42卷 156-177页

作者： Jingjun zhao Wenjiao zhao Yang Xu School of Mathematics Harbin Institute of TechnologyHarbin 150001China

This paper deals with the numerical approximation for the time fractional diffusion problem with fractional dynamic boundary *** well-posedness for the weak solutions is studied.A direct discontinuous Galerkin approach is used in spatial direction under the uniform meshes,together with a second-order Alikhanov scheme is utilized in temporal direction on the graded mesh,and then the fully discrete scheme is ***,the stability and the error estimate for the full scheme are analyzed in *** experiments are also given to illustrate the effectiveness of the proposed method.

关键词： Time fractional diffusion equation Numerical stability Convergence

Finite-Time Thermodynamic Simulation of Circulating Direct Condensation Heat Recovery on Chillers

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

Journal of Power and Energy Engineering 2024年第1期12卷 1-14页

作者： Zhixin Yang feihu Chen Liping Wang Guangcai Gong Changsha Maxxom High-Tech Ltd. Changsha China College of Civil Engineering Hunan University Changsha China School of Civil Engineering Hefei University of Technology Hefei China

A time series model is used in this paper to describe the progress of circulating direct condensation heat recovery of the compound condensing process (CCP) which is made of two water cooling condensing processes in series for a centrifugal chiller in the paper. A finite-time thermodynamics method is used to set up the time series simulation model. As a result, an upper bound of recoverable condensation heat for the compound condensing process is obtained which is in good agreement with experimental result. And the result is valuable and useful to optimization design of condensing heat recovery.

关键词： Condensation Heat Recovery Compound Condensing Process Time Series Finite-Time Thermodynamics

A water-stable high-voltage P3-type cathode for sodium-ion batteries

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

Chinese Chemical Letters 2024年第9期35卷 507-513页

作者： Shengyu zhao Xuan Yu Yufeng zhao Institute for Sustainable Energy&College of Sciences Shanghai UniversityShanghai 200444China

The Na-deficient P3-type layered oxide cathode material usually experience complex in-plane Na^(+)/vacancy ordering rearrangement and undesirable P3-O3 phase transitions in the high-voltage region,leading to inferior cycling ***,they exhibit unsatisfactory stability when exposed to water for extended *** address these challenges,we propose a Cu/Ti co-doped P3-type cathode material(Na_(0.67)Ni_(0.3)Cu_(0.03)Mn_(0.6)Ti_(0.07)O_(2)),which effectively mitigates Na^(+)/vacancy ordering and suppresses P3-O3 phase transitions at high *** a result,the as-prepared sample exhibited outstanding cyclic performance,with 81.9%retention after 500 cycles within 2.5–4.15 V,and 75.7%retention after300 cycles within 2.5–4.25 ***,it demonstrates enhanced Na^(+)transport kinetics during desodiation/sodiation and reduced growth of charge transfer impedance(R_(ct))after various ***,the sample showed superb stability against water,exhibiting no discernible degradation in structure,morphology,or electrochemical *** co-doping strategy provides new insights for innovative and prospective cathode materials.

关键词： Sodium ion batteries P3-type materials Phase transition Na^(+)/vacancy ordering Water-stable cathode

Resilient control of flexible hypersonic vehicles against unmatched distributed faults

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第5期37卷 60-70页

作者： Dong zhao Wenjing REN School of Artificial Intelligence Anhui UniversityHefei 230601China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

This paper studies a robust fault compensation and vibration suppression problem of flexible hypersonic *** controlled plant is represented by a cascade system composed of a nonlinear Ordinary Differential Equation(ODE)and an Euler-Bernoulli Beam Equation(EBBE),in which the vibration dynamics is coupled with the rigid dynamics and suffers from distributed faults.A state differential transformation is introduced to transfer distributed faults to an EBBE boundary and a longitudinal dynamics is refined by utilizing T-S fuzzy IF-THEN rules.A novel T-S fuzzy based fault-tolerant control algorithm is developed and related stability conditions are *** robust exponential stability and well-posedness are proved by using the modified l_(0)-semigroup based Lyapunov direct approach.A simulation study on the longitudinal dynamics of flexible hypersonic vehicles effectively verifies the validity of the developed theoretical results.

关键词： Flexible hypersonic vehicles ODE-EBBE cascade Robust exponential stability Unmatched distributed fault compensation Vibration suppression