检索结果-南通市图书馆

文化资本视野下的农村中小学现代远程教育工程

在线全文

学校读者我要写书评

暂无评论

现代教育技术 2012年第7期22卷 73-77页

作者：俞树煜李禹杉杨莉娟西北师范大学教育技术与传播学院甘肃兰州730070

文化资本理论是法国社会学家皮埃尔.布迪厄(Pierre Bourdieu)的社会学理论的重要内容,文化资本理论为全面审视农村中小学现代远程教育工程提供了全新的视角。文章从文化资本的视角对"农远工程"进行了全面的审视,经过分析发现,"农远工程... 详细信息

文化资本理论是法国社会学家皮埃尔.布迪厄(Pierre Bourdieu)的社会学理论的重要内容,文化资本理论为全面审视农村中小学现代远程教育工程提供了全新的视角。文章从文化资本的视角对"农远工程"进行了全面的审视,经过分析发现,"农远工程"除了为农村基础教育提供优质教育资源外,更重要的是"农远工程"重构了农村的教育文化资本,直接增加了农村学校文化资本,直接或间接地发展了家庭文化资本和农村社区文化资本,从而推动了农村基础教育的发展。但也要看到,"农远工程"也强化了农村教育文化资本的"主流化"倾向,会影响到农村基础教育的均衡发展。

关键词：文化资本农村中小学现代远程教育工程重构农村基础教育

A self-adaptive inorganic in-situ separator by particle crosslinking for nonflammable lithium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 469-480页

作者： Jiarui Yang Jiuzhou liu Wenrui Cai Ziyu Zhao shan Wang Lu He shanshan Lv Zhiwei Zhu Zhongfeng Ji Guojiang Wen Hua li yuanming Zhai Xuewei Fu Wei Yang yu Wang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University

All-safe liquid-state lithium-ion batteries(ASLS-liBs) is of great interest as they can potentially combine the safety of all-solid-state batteries with the high performance and low manufacturing cost of traditional liquid-state liBs. However, the practical success of ASLS-liBs is bottlenecked by the lack of advanced separator technology that can simultaneously realize high performances in puncturing-tolerability,fire-resistance, and importantly, wetting-capability with non-flammable liquid-electrolytes. Here, we propose a concept of inorganic in-situ separator(IISS) by hybrid-sol physical crosslinking directly onto the electrode surface to address the above challenges. Particularly, the hybrid-sol is designed with silica nanoparticles as the building block and poly(vinylidene difluoride) nanoparticles as the crosslinking agent. The critical factors for controlling the IISS microstructures and properties have been systematically investigated. The advantages of the IISS have been confirmed by its fast wetting with various fireresistant liquid-electrolytes, customizable thickness and porous structures, robust interface with planar or three-dimensional(3D)-structured electrodes, and importantly, unexpected self-adaptability against puncturing. Enabled by the above merits, a fire-resistant ASLS-liB is successfully assembled and demonstrated with stable electrochemical performance. This sol-crosslinked IISS may open an avenue for the studies on the next-generation separator technology, cell assembling, solid electrolyte processing as well as non-flammable secondary batteries.

关键词： Silica nanoparticles

Crop Yield Response to Water and Fertilizer in Loess Tableland of China：A Field Research

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 1995年第3期5卷 259-266页

作者： liU WEN-ZHAO and li yu-shan(State Key Laboratory of Soil Erusion and Dryland Farming on Loess Plateau, Northwest Institute of Soiland Water Conservation, Chinese Academy of Sciences, Yangling 712100 (China) )

This paper describes a field research on crop yield response to water and fertilizer in Changwu tablelandof the Loess Plateau. Under the current level of land management in this areai low fertility of soil is thefirst yield-limiting factor and water deficit is the second. At a given fertility level, the relationship betweencrop yield and its water consumption is parabolic. Within a certain range of soil moisture, the soil wateravailability to crop is not sharply decreased with its markedly decreasing content. Because of this relativelyhigh availability and the high reserve of soil water at the early stage of crop growth, drought due to inadequateor poorly distributed rainfall becomes less serious. High fertilizer input, improved crop variety and optimumcnltivation techniqne can give a 50-100% yield increment of dryland crops in the loess tableland.

关键词： grain yield Loess Plateau soil fertility soil moisture

在线全文

学校读者我要写书评

暂无评论

耦合微带线的散射参数特性分析

电子与信息学报 2008年第11期30卷 2755-2758页

作者：李丽平李玉山贾琛潘健张木水西安电子科技大学电路CAD研究所西安710071

针对耦合微带线的散射参数在一些频率点处呈现出波峰、波谷现象,该文根据微波网络理论,从两根平行微带线的奇模和偶模的散射参数出发,推导出四端口网络散射参数的波峰、波谷处频率与并行长度和线间距的关系。同时分别在频域和时域研究... 详细信息

针对耦合微带线的散射参数在一些频率点处呈现出波峰、波谷现象,该文根据微波网络理论,从两根平行微带线的奇模和偶模的散射参数出发,推导出四端口网络散射参数的波峰、波谷处频率与并行长度和线间距的关系。同时分别在频域和时域研究了两根平行微带结构的插入损耗对信号传输的影响。经分析发现,由于微带线间的耦合,波峰、波谷处的频率随线间距增大而提高,随长度增大而降低;而且在串扰产生的同时,所传输的信号也有一定程度的衰减。

关键词：微带线散射参数(S参数) 奇模偶模

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen Hu Xinwei li Qianqian liang li Xu Changsheng Ding yu liu Yanfeng Gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies

Nanostructured ZnO/BiVO_(4)I-scheme heterojunctions for piezocatalytic degradation of organic dyes via harvesting ultrasonic vibration energy

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 488-497页

作者： Yiling li Xiaoyao yu Yingjie Zhou Yao lin Ying Wu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004China

BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step *** resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine B(RhB)unde mechanical vibrations,they exhibit superior activity compared to pure *** 40wt%ZnO/BiVO_(4)heterojunction composite displayed the highest activity,along with good stability and *** enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole ***,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active ***,ZnO/BiVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.

关键词： piezoelectric catalytic heterojunction dye degradation ultrasonic vibration

基于PCA/Snake混合模型的运动目标外轮廓求解

在线全文

学校读者我要写书评

暂无评论

模式识别与人工智能 2007年第3期20卷 313-318页

作者：李春明李玉山张大朴刘洋西安电子科技大学计算机辅助设计研究所

提出一种基于 PCA/Snake 混合模型的运动目标外轮廓求解算法.该算法首先基于改进的主成分分析(PCA)模型和特征前景进行运动目标检测.然后根据目标的检测结果,基于 Snake 模型精确求解出运动目标的外轮廓.实验结果表明,本文算法提取的运... 详细信息

提出一种基于 PCA/Snake 混合模型的运动目标外轮廓求解算法.该算法首先基于改进的主成分分析(PCA)模型和特征前景进行运动目标检测.然后根据目标的检测结果,基于 Snake 模型精确求解出运动目标的外轮廓.实验结果表明,本文算法提取的运动目标位置较精确,可同时提取图像序列中的多运动目标,且运算速度较快.

关键词：主成分分析(PCA) 动态轮廓模型(Snake) 运动目标外轮廓提取特征前景

电子电路板级模块高效设计环境参数库共享技术

在线全文

学校读者我要写书评

暂无评论

计算机集成制造系统-CIMS 2001年第4期7卷 62-65页

作者：扈婉丽杨莉李玉山西安电子科技大学电路CAD所陕西西安710071

提出了器件符号对应法 ,实现电子电路板级模块高效设计环境中各种EDA工具的参数库的转换和共享 ,并给出了PROTEL的原理图在VIEWLOGIC和PSPICE中进行仿真的应用实例。实践证明。

关键词：电子电路板级模块高效设计环境参数库共享仿真

在线全文

学校读者我要写书评

暂无评论

芯片动态门限静态功耗的优化技术

电子科技大学学报 2009年第3期38卷 443-446页

作者：李先锐葛海波来新泉李玉山西安电子科技大学电路设计研究所西安710071 西安邮电学院电信系西安710061

提出了一种双阈值电压的动态门限静态功耗优化算法。该算法通过直接统计电路门级节点的松弛裕度,利用静态时序分析其最大松弛裕度及邻节点松弛裕度特征,区分电路中的关键与非关键节点并分步调整其相应的阈值电压,从而有效地实现了对CMO... 详细信息

提出了一种双阈值电压的动态门限静态功耗优化算法。该算法通过直接统计电路门级节点的松弛裕度,利用静态时序分析其最大松弛裕度及邻节点松弛裕度特征,区分电路中的关键与非关键节点并分步调整其相应的阈值电压,从而有效地实现了对CMOS电路静态功耗的优化设计。基于ISCA85基准实验电路集,采用该技术和以往的算法进行了对比验证。结果表明,该算法在不降低静态功耗优化效率的同时,优化时间缩短了95%以上,适合于超大规模电路静态功耗优化。

关键词：双阈值动态门限静态功耗优化静态时序分析