检索结果-南通市图书馆

A novel method to prepare metal oxide electrode:Spin-coating with thermal decomposition

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第3期22卷 354-357页

作者： Hao Xu Wei yan cheng li Tang Department of Environmental Science and Technology Xi'an Jiaotong University Xi'an 710049 China

In this work,we propose a new spin-coating method coupling with high thermal decomposition,to prepare the tin-antimony（Sn-Sb） oxide *** character of the spin-coating electrode was compared with the dip-coating electrode through X-ray diffraction（XRD）,scanning electron microscopy（SEM）,accelerated life test,cyclic voltammetry,and electrolytic degradability. The results showed that the spin-coating electrode had a better defined crystal form,a smoother and more compact surface than that of the dip-coating *** time of the spin-coating electrode was determined to be longer than 15 h,and it was less than 2 min for the dip-coating *** characterization analysis showed that the electrolytic degradability of the spin-coating electrode is better than that of the dip-coating electrode.

关键词： Spin-coating Dip-coating Thermal decomposition Electro properties

Modeling of air quality with a modified two-dimensional Eulerian model: A case study in the Pearl River Delta (PRD) region of China

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2007年第5期19卷 572-577页

作者： cheng yan-li BAI Yu-hua li Jin-long liU Zhao-rong College of Environmental Sciences Peking University Beijing 100871 China

A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta （PRD） region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols （SOA） concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3^-, NH4^＋, SO4^2-, and SOA were calculated in the fine particle size range （〈2.5 μm）. The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign （IMC）. Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio.

关键词： air quality model numerical simulation secondary organic aerosol inorganic aerosol

在线全文

学校读者我要写书评

暂无评论

聚合物荧光材料的合成与应用

广州化工 2024年第3期52卷 4-7页

作者：成莉燕李芸菲冯丹陶小娟兰州资源环境职业技术大学环境与化工学院甘肃兰州730021

聚合物荧光材料克服了小分子荧光分子的缺点,在实际应用过程具有明显的特性,应用越来越广泛系统总结水溶性、非水溶性和两亲性三大类荧光聚合物材料的合成方法,归纳了荧光聚合物材料在光电器件、防伪材料、检测材料和生物医药材料领域... 详细信息

聚合物荧光材料克服了小分子荧光分子的缺点,在实际应用过程具有明显的特性,应用越来越广泛系统总结水溶性、非水溶性和两亲性三大类荧光聚合物材料的合成方法,归纳了荧光聚合物材料在光电器件、防伪材料、检测材料和生物医药材料领域的应用,最后对未来发展趋势进行了预测。

关键词：荧光荧光聚合物合成应用

Fault Detection for a Class of Impulsive Switched Systems

在线全文

学校读者我要写书评

暂无评论

International Journal of Automation and computing 2014年第2期11卷 223-230页

作者： Qing-Yu Su yan-cheng li Xing-Ze Dai Jian li School of Automation Engineering Northeast Dianli University

The problem of fault detection for a class of nonlinear impulsive switched systems is investigated in this paper. Fault detection filters are designed such that the augmented systems are stable, and the residual error signal generated by the filters guarantees the H∞ performance for disturbances and faults. Sufficient conditions for the design of fault detection(FD) filters are presented by linear matrix inequalities. Moreover, the filter gains are characterized according to a solution of a convex optimization. Finally, an example derived from a pulse-width-modulation-driven boost converter is given to illustrate the effectiveness of the FD design approach.

关键词： Impulsive switched systems fault detection(FD) H∞ performance dwell time filter design.

Two-way shape memory effect in a Ti-Zr-Nb-Ta high-temperature shape memory alloy

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1257-1262页

作者： cheng-yang Xiong Tuo li Jun Wang yan li School of Materials Science and Engineering Beihang UniversityBeijing100191China

The two-way shape memory effect in a Ti-18.5Zr-10Nb-3.5Ta high-temperature shape memory alloy was investigated.X-ray diffraction measurem ent shows that the alloy is composed of orthorhombicα"-martensite.ωphase is not found in Ti-18.5Zr-10Nb-3.5Ta alloy due to the suppressing effect of Ta ***α"-martensite laths are found in the transmission electron microscope observation;after the bending deformation,there appear a lot of *** alloy exhibits a shape memory strain of 3.8%aud a high reverse martensite transformation start temperature of 464 *** maximum two-way shape memory strain of 1.2%is obtained in the alloy with the prebending training strain of 10%.The mechanism can be ascribed to the effect of internal stress field caused by dislocations.

关键词： Ti-Zr Shape memory alloys Two-way shape memory effect

Random gradient-free method for online distributed optimization with strongly pseudoconvex cost functions

在线全文

学校读者我要写书评

暂无评论

Control Theory and Technology 2024年第1期22卷 14-24页

作者： Xiaoxi yan cheng li Kaihong Lu Hang Xu School of Electrical and Information Engineering Jiangsu UniversityZhenjiang212013JiangsuChina College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao266590ShandongChina

This paper focuses on the online distributed optimization problem based on multi-agent systems. In this problem, each agent can only access its own cost function and a convex set, and can only exchange local state information with its current neighbors through a time-varying digraph. In addition, the agents do not have access to the information about the current cost functions until decisions are made. Different from most existing works on online distributed optimization, here we consider the case where the cost functions are strongly pseudoconvex and real gradients of the cost functions are not available. To handle this problem, a random gradient-free online distributed algorithm involving the multi-point gradient estimator is proposed. Of particular interest is that under the proposed algorithm, each agent only uses the estimation information of gradients instead of the real gradient information to make decisions. The dynamic regret is employed to measure the proposed algorithm. We prove that if the cumulative deviation of the minimizer sequence grows within a certain rate, then the expectation of dynamic regret increases sublinearly. Finally, a simulation example is given to corroborate the validity of our results.

关键词： Multi-agent system Online distributed optimization Pseudoconvex optimization Random gradient-free method

Scenarios analysis and performance assessment of blockchain integrated in 6G scenarios

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

Science China(Information Sciences) 2024年第7期67卷 5-26页

作者： Bo li Guanjie cheng Honghao GAO Xueqiang yan Shuiguang DENG College of Computer Science and Technology Zhejiang University College of Computer Science and Technology Shanghai University 2012 Lab Huawei Technologies Co. Ltd.

Emerging applications such as smart city infrastructures and virtual reality landscapes are setting rigorous benchmarks for 6G mobile networks, requiring elevated levels of confidentiality, integrity, nonrepudiation, authentication, and stringent access controls. Blockchain technology is heralded as a transformative enabler for meeting 6G standards, owing to its intrinsic attributes. However, a gap exists in the holistic investigation of blockchain's applicability in 6G realms, particularly addressing the “whether”, “when”, and“how” of its deployment. Present research trails in developing robust methodologies to gauge blockchain's efficacy within 6G use cases. Addressing this, our study introduces a novel confluence of blockchain with 6G networks, where data resides in distributed Hash tables(DHTs) while their hashes are secured in distributed ledger technology(DLT), harnessing blockchain's core strengths-immutability, traceability, and fortified security. We delineate seven specific 6G use cases poised for enhancement through blockchain integration,and scrutinize the rationale, nature, and timing of this convergence. Furthermore, we devise a comprehensive methodology for assessing blockchain's performance metrics and scalability in 6G environments. Our extensive experimental analyses evaluate the synergistic performance of this integration, revealing that the Quorum blockchain satisfactorily supports 80% of 6G scenarios. The findings suggest that, with appropriate configurations, consortium blockchains are well-equipped to fulfill the demanding performance and scalability requisites of 6G networks.

关键词： blockchain distributed ledger technology (DLT) 6G performance assessment 6G scenarios analysis transaction arrival rate

Sustainable production of high-energy-density jet fuel via cycloaddition reactions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第8期95卷 712-722,I0016页

作者： yan-cheng Hu Yingying Zhao Ning li Jing-Pei Cao School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou 221116JiangsuChina School of Education Science Jiangsu Normal UniversityXuzhou 221116JiangsuChina CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Developing an energy supply-chain based on renewable biomass holds great potential to build a low carbon ***-energy-density(HED)jet fuel,featuring unique fused/strained cycloalkanes,is of great significance for volume-limited military aircrafts,as their high density and combustion heat can extend flight duration and increase the ***,the exploration of biomass-based routes towards HED fuel has drawn much attention over the past *** reaction features rapid construction of various carbocycles in an atom-and step-economical *** elegant strategy has been widely applied in the manufacture of sustainable HED *** we carefully summarize the progress achieved in this fascinating area and the review is categorized by the cycloaddition patterns including[4+2],[2+2],[4+4],and[2+1]***,the energy densities of the as-prepared biofuels and petroleumbased fuels(conventional Jet-A and advanced JP-10)are also *** review will provide important insights into rational design of new HED fuel with different ring-types/sizes and inspire the chemists to turn those literature studies into practical applications in military field.

关键词： High-energy-density fuel Biomass-based chemicals Cycloaddition Cycloalkanes Catalysis

在线全文

学校读者我要写书评

暂无评论

西安市0~2岁婴幼儿睡眠状况调查分析

海南医学 2024年第15期35卷 2217-2221页

作者：任姣姣程艳丽高红李红娟王朝晖西安市人民医院(西安市四医院)儿童保健科陕西西安710004

目的了解西安市0~2岁婴幼儿睡眠状况,为婴幼儿睡眠问题的防治提供参考依据。方法于2022年10月1日至2023年10月1日调查在西安市人民医院(西安市第四医院)儿童保健科接受儿童保健服务的0~2岁婴幼儿13831例。按年龄分为0~3月龄组、4~11月... 详细信息

目的了解西安市0~2岁婴幼儿睡眠状况,为婴幼儿睡眠问题的防治提供参考依据。方法于2022年10月1日至2023年10月1日调查在西安市人民医院(西安市第四医院)儿童保健科接受儿童保健服务的0~2岁婴幼儿13831例。按年龄分为0~3月龄组、4~11月龄组和1~2岁组。由家长现场完成婴幼儿简明睡眠问卷。采用Kruskal-wallis秩和检验和χ~2检验进行统计学分析。结果发放问卷13831份,有效问卷13565份,有效问卷率为98.1%。其中,男童6991例(51.5%),女童6574例(48.56%);0~3月龄组、4~11月龄组、1~2岁组分别为3018例、7018例、3529例。西安市0~2岁婴幼儿睡眠问题的发生率为58.1%(7882/13565),夜醒问题的发生率最高(32.9%),其次为入睡困难(31.7%)。各年龄组婴幼儿睡眠时间、睡眠问题、睡眠习惯比较差异均有统计学意义(P0.05),不同睡眠地点的入睡时间比较差异无统计学意义(P>0.05)。结论西安市0~2岁婴幼儿睡眠问题发生率较高,需加强对照护者进行婴幼儿睡眠知识的宣教,减少婴幼儿睡眠问题的发生,促进婴幼儿睡眠健康。

关键词：婴幼儿睡眠时间睡眠问题夜醒睡眠习惯

维普期刊数据库博看期刊