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飞机拦阻网微机自动立网系统的设计
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作者 钟子晶 王德功 常硕 《计算机测量与控制》 CSCD 2006年第4期545-547,共3页
分析了所研制的飞机拦阻网微机自动立网系统的工作原理、组成和功能;该立网系统是飞机拦阻设备中自动立网的控制部分, 能够计算飞机在跑道终端的滑跑速度,在飞机的滑跑速度不符合安全规定的情况下,可以快速、准确地做出判断,产生立网控... 分析了所研制的飞机拦阻网微机自动立网系统的工作原理、组成和功能;该立网系统是飞机拦阻设备中自动立网的控制部分, 能够计算飞机在跑道终端的滑跑速度,在飞机的滑跑速度不符合安全规定的情况下,可以快速、准确地做出判断,产生立网控制信号, 立起拦阻网拦截飞机,同时发出报警信号;在飞机拦阻网中应用该自动立网系统能够提高飞机安全着陆的可靠性,有着重要的军事意义和经济效益。 展开更多
关键词 微机 拦阻 激光 自动立网
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论南丝绸之路四位一体多渠道的立网模式
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作者 吴克烈 《国内外经济管理》 1992年第5期26-29,共4页
关键词 对外贸易 丝绸 中国 立网模式
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涂覆式阻燃密目立网
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《江苏科技信息》 2002年第12期50-50,共1页
江苏省江都市第一绳网厂研制生产的涂覆式阻燃密目立网及材料丝采用国产化纤原料,涂层由多种化工原料配制,形成内外两层结构的新材料,经织造模压成网片,具有强力高、韧性好、阻燃性能强、抗紫外线辐射、耐腐蚀、不易老化且质优价廉... 江苏省江都市第一绳网厂研制生产的涂覆式阻燃密目立网及材料丝采用国产化纤原料,涂层由多种化工原料配制,形成内外两层结构的新材料,经织造模压成网片,具有强力高、韧性好、阻燃性能强、抗紫外线辐射、耐腐蚀、不易老化且质优价廉等特点,产品质量、生产工艺处于国内领先位,填补国内空白,并获国家专利。 展开更多
关键词 涂覆式阻燃密目立网 化纤原料 织造 模压 应用 复合材料
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北斗卫星导航定位基准实时服务格网化方法——以山东省为例
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作者 高士民 袁锐 +2 位作者 田茂荣 刘植 徐亚力 《山东国土资源》 2024年第1期58-64,共7页
当前,北斗卫星导航定位基准实时服务以虚拟参考站定位模式为主,随着用户的不断增加,导致平台端运算压力陡增。针对该问题,提出了一种融合格网与地形信息的立体格网定位方法,并对格网划分策略进行了系统性研究。以山东省北斗卫星导航定... 当前,北斗卫星导航定位基准实时服务以虚拟参考站定位模式为主,随着用户的不断增加,导致平台端运算压力陡增。针对该问题,提出了一种融合格网与地形信息的立体格网定位方法,并对格网划分策略进行了系统性研究。以山东省北斗卫星导航定位基准站网为例,选择16个野外测试点对格网化后的实时服务进行了实测验证,平面外符合定位精度优于1.5cm,高程外符合定位精度优于2.0cm。实现了厘米级增强定位,在满足网络实时定位精度的前提下,大幅降低数据中心的运算压力。 展开更多
关键词 卫星导航 基准站 体格定位 RTK
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现代林果科技示范园采用矮砧密植立格架网高纺锤形栽培技术的优势特点分析
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作者 刘建华 杨晓慧 《新农村(黑龙江)》 2018年第6期117-117,共1页
涿鹿县现代林果科技示范园建设,采用矮砧密植立格架网高纺锤形栽培技术,具有高品质、高产出、早挂果、早收回投资、便于机械化、设施化、标准化作业的突出优点.有利于推动基地及涿鹿县苹果栽培制度与国际的接轨。
关键词 涿鹿县 现代林果 科技示范园 矮砧密植 格架 高纺锤形 优势特点
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安全网产品2001年3季度抽查结果分析
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作者 赵留根 《中国个体防护装备》 2002年第1期18-19,共2页
安全网产品包括平网、立网和密目式安全立网,是建筑、矿山、造船等行业高空作业场所防止人员坠落或坠物伤害必须使用的劳动保护用品,尤以建筑业的用量最大.据有关部门统计,近几年北京市建筑市场的年均开竣工建筑面积在6000万平方米左右... 安全网产品包括平网、立网和密目式安全立网,是建筑、矿山、造船等行业高空作业场所防止人员坠落或坠物伤害必须使用的劳动保护用品,尤以建筑业的用量最大.据有关部门统计,近几年北京市建筑市场的年均开竣工建筑面积在6000万平方米左右,由此推算,仅北京建筑行业的安全网年需求量近100万张.面对全国城市、乡镇和农村随处可见的房地产开发,建筑业必须使用的安全网需求量大幅增加,刺激了安全网市场的升温.一些原来生产渔网、养殖网和民用窗纱的企业见到安全网市场的利好,也生产安全网.据不完全统计,全国目前已有近200家取得生产许可证的安全网生产企业,而无证企业更不计其数. 展开更多
关键词 安全产品 2001年3季度 质量抽查分析 商空作业 立网 密日式安全立网
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一网听天下——中国广播网2010年改版解读
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作者 隋欣 《中国广播》 2011年第5期83-85,共3页
中国广播网的改版历史在一定程度上记录了中央电台"重塑"广播的探索实践。再次改版后的中国广播网定位于打造全球最大的中文音频网络门户,使网友在便捷中享受"一网听天下";秉承新闻立网的理念,在网络中放大民声与民... 中国广播网的改版历史在一定程度上记录了中央电台"重塑"广播的探索实践。再次改版后的中国广播网定位于打造全球最大的中文音频网络门户,使网友在便捷中享受"一网听天下";秉承新闻立网的理念,在网络中放大民声与民意;重视分享与互动,从而提升受众的主体地位。 展开更多
关键词 中国广播 听天下 新闻立网 受众主体
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帝枇建筑模网在我国建筑工程中的应用 被引量:3
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作者 刘岩 荣利民 王来福 《施工技术》 CAS 北大核心 2001年第8期29-30,共2页
关键词 建筑模 施工方法 拼缝
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“网红现象”下农村青少年价值观教育困境与突围——基于Z村田野调研的思考 被引量:2
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作者 许慧妍 《中小学德育》 2021年第1期16-20,共5页
后疫情时代,互联网经济催生的"网红现象"走入农村青少年视野,手机成瘾的现象呈上升趋势。基于教育人种志的研究方法与同一性理论,在珠三角Z村进行长达2年的田野调研发现,网红经济从内容引导、社群运营等方面影响青少年的价值... 后疫情时代,互联网经济催生的"网红现象"走入农村青少年视野,手机成瘾的现象呈上升趋势。基于教育人种志的研究方法与同一性理论,在珠三角Z村进行长达2年的田野调研发现,网红经济从内容引导、社群运营等方面影响青少年的价值取向和价值标准,多渠道影响其价值选择。价值观教育需从社会参与、学校指导、家庭实施方面,有针对性地通过加强网络监管机制,营造积极向上的媒体舆论氛围,创新德育课程内容与活动形式,重视家风家规传承,提升家长网络媒介素养等方式寻求突围。 展开更多
关键词 家校同构 家校合力 教育治理 德树人“红”现象 农村青少年价值观教育 田野调研
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切顶留巷成套支护设备的研究与应用 被引量:5
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作者 孙如钢 刘国柱 钱洋喜 《煤矿机械》 2016年第2期108-110,共3页
介绍了一种应用切顶泄压短悬臂梁留巷矿压理论,全新思路的沿空留巷支护方式—切顶留巷成套支护设备,切顶留巷成套支护设备是一种具有支护、防护、挡矸、切顶、清矸、铺设立网及导网、自移自调等多种功能的,适用性强、适用范围广的全新... 介绍了一种应用切顶泄压短悬臂梁留巷矿压理论,全新思路的沿空留巷支护方式—切顶留巷成套支护设备,切顶留巷成套支护设备是一种具有支护、防护、挡矸、切顶、清矸、铺设立网及导网、自移自调等多种功能的,适用性强、适用范围广的全新型留巷支护设备,包括留巷端头支架和留巷切顶支架两部分。该设备的应用比传统的沿空留巷支护方式投资少、操作简单、安全可靠、可完全重复利用,是当前无煤柱沿空留巷开采较为先进有效的支护方式。 展开更多
关键词 切顶留巷 全封闭挡矸 立网铺设 锚索避让 支护力调配 切顶支架
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自旋流刷洗式地表水处理过滤器的设计与试验 被引量:1
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作者 王超 胡斌 +3 位作者 王佳萍 潘峰 范文波 何浩猛 《农机化研究》 北大核心 2020年第10期145-151,共7页
过滤器是灌溉系统进行表面水处理的关键设备,其过滤性能直接影响灌溉系统的灌溉能力。为此,针对地表水处理过滤器的研究现状,在不影响过滤器过滤效率的前提下设计了一种自旋流刷洗式地表水处理过滤器,并提出了一种水力驱动代替传动电机... 过滤器是灌溉系统进行表面水处理的关键设备,其过滤性能直接影响灌溉系统的灌溉能力。为此,针对地表水处理过滤器的研究现状,在不影响过滤器过滤效率的前提下设计了一种自旋流刷洗式地表水处理过滤器,并提出了一种水力驱动代替传动电机驱动的立网刷洗式,能够提高防盗系数、安全系数,且能够降低成本。同时,详细介绍了过滤器自旋流泵的结构及工作原理,确定了自旋流泵具体结构参数和传动机构的结构。通过对过滤器过滤前后的水中杂质含量的对比,确定杂质处理效率,并应用Design expert进行数据分析,对设计数值进行优化,确定该过滤器的自旋流泵性能与杂质处理效果的最佳组合值。 展开更多
关键词 地表水处理 立网过滤器 旋流驱动 优化
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HARDWARE-BASED VOXELIZATION FOR TRUE 3-D DISPLAY 被引量:5
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作者 谭皓 杨忠 +1 位作者 李玉峰 沈春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第1期59-64,共6页
An efficient voxelization algorithm is presented for polygonal models by using the hardware support for the 2 D rasterization algorithm and the GPU programmable function to satisfy the volumetric display system. The v... An efficient voxelization algorithm is presented for polygonal models by using the hardware support for the 2 D rasterization algorithm and the GPU programmable function to satisfy the volumetric display system. The volume is sampled into slices by the rendering hardware and then slices are rasterated into a series of voxels. A composed buffer is used to record encoded voxels of the target volume to reduce the graphic memory requirement. In the algorithm, dynamic vertexes and index buffers are used to improve the voxelization efficiency. Experimental results show that the algorithm is efficient for a true 3-D display system. 展开更多
关键词 computer graphics VOXELIZATION volumetric display mesh model
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Study on Guidance Law of UAV Net Recovery System
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作者 张怡 赵少松 +1 位作者 王永生 张玉琢 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第1期64-67,共4页
The design and realization of a net recovery system is introduced, which can recover UAV (unmanned aerial vehicle) reliably and safely. The mathematical model is built, and the horizontal and vertical guidance law is ... The design and realization of a net recovery system is introduced, which can recover UAV (unmanned aerial vehicle) reliably and safely. The mathematical model is built, and the horizontal and vertical guidance law is studied based on the aerodynamic parameters and actual flying trial data of a certain UAV. The simulation result shows that this system can realize the recovery safely, stably and accurately. 展开更多
关键词 无人飞行器 立网回收系统 制导律 模拟 气动力学
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Semantics-Based Compliance An a lys is o f N e two rk S e cu rity Policy Hie ra rch ie s 被引量:1
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作者 Yao Shan Xia Chunhe +2 位作者 Hu Junshun Jiao Jian Li Xiaojian 《China Communications》 SCIE CSCD 2012年第7期22-35,共14页
Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflect... Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflects the validity of the policy hierarchies yielded by the automated policy refinement process. However, little attention has been paid to the evaluation of the compliance between the derived lower level policy and the higher level policy. We present an ontology based on Ontology Web Language (OWL) to describe the semantics of security policy and their implementation. We also propose a method of estimating the semantic similarity between a given 展开更多
关键词 policy refinement network security policy semantic similarity ontology
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Modelling and Implementation of Multi-source Isolated Microgrid Using Virtual Synchronous Generator Technology
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作者 CHEN Xing QIAN Shengnan +2 位作者 LI Fei GE Zhaohui CAO Xin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第5期747-757,共11页
To improve the living standards,economical efficiency and environmental protection of isolated islands,remote areas and other areas with weak electric power facilities construction,a multi-source independent microgrid... To improve the living standards,economical efficiency and environmental protection of isolated islands,remote areas and other areas with weak electric power facilities construction,a multi-source independent microgrid system is studied,including diesel generators,photovoltaic power generation system,wind power generation system and energy storage unit.Meanwhile,in order to realize the voltage and frequency stability control of AC bus of multisource microgrid,the virtual synchronous generator technology is introduced into the energy storage unit,and the charge and discharge control of the energy storage battery are simulated as the control behavior characteristics of synchronous motors,so as to provide damping and inertia support for the microgrid.The operation mode and control principle of each energy subsystem are expounded and analyzed.The algorithm principle of virtual synchronous generator and the control method of energy storage unit are given.Then,the working modes of the microgrid system under different environmental conditions are analyzed,and the multi-source microgrid system simulation model is built based on MATLAB/Simulink.The simulation results show that the microgrid system can run stably under different working modes and the energy storage unit using the virtual synchronous generator technology can provide good voltage and frequency support for the microgrid system.Finally,experiments verify the supporting function of energy storage unit on the voltage and frequency of the microgrid system. 展开更多
关键词 isolated microgrid wind/solar/diesel/storage virtual synchronous generator MODELLING
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On Restricted Connectivity and Extra Connectivity of Hypercubes and Folded Hypercubes 被引量:13
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作者 徐俊明 朱强 +1 位作者 侯新民 周涛 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期203-207,共5页
Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whos... Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whose deletion disconnects G and every remaining component has the minimum degree of vertex at least h; and the h-extra connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, if any, whose deletion disconnects G and every remaining component has order more than h. This paper shows that for the hypercube Qn and the folded hypercube FQn, κ1(Qn)=κ(1)(Qn)=2n-2 for n≥3, κ2(Qn)=3n-5 for n≥4, κ1(FQn)=κ(1)(FQn)=2n for n≥4 and κ(2)(FQn)=4n-4 for n≥8. 展开更多
关键词 CONNECTIVITY conditional connectivity restricted connectivity extra connectivity HYPERCUBE folded hypercube
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Influence of site conditions on ground motion at far field loess sites during strong earthquake 被引量:2
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作者 WU Zhi-jian WANG Lan-min +3 位作者 WANG Ping CHEN Tuo SHI Hang YANG Xiao-peng 《Journal of Central South University》 SCIE EI CAS 2013年第8期2333-2341,共9页
Loess is widely distributed in China and the Loess Plateau is one of the major areas where strong earthquakes often take place. The seismic amplification effects were discovered in the Plateau during the Wenchuan Ms8.... Loess is widely distributed in China and the Loess Plateau is one of the major areas where strong earthquakes often take place. The seismic amplification effects were discovered in the Plateau during the Wenchuan Ms8.0 earthquake and some other strong events. Based on earth tremor observation, borehole exploration and site seismic response analysis, the site effects of topography of Loess Yuan on ground motion were investigated in details. The earth tremor investigation shows that predominant frequencies at the bottom sites of Loess Yuan are greater than those at the top obviously. The sites seismic response analysis shows that the Loess Yuan may amplify peak ground acceleration (PGA) by 1.44 2.0 times. Therefore, site effects of mountains and loess topography on ground motion should be taken account into in seismic design in loess regions. 展开更多
关键词 earth tremor borehole exploration site effects seismic response
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MGB probe assay for rapid detection of mtDNA11778 mutation in the Chinese LHON patients by real-time PCR 被引量:2
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作者 Jian-yong WANG Yang-shun GU +4 位作者 Jing WANG Yi TONG Ying WANG Jun-bing SHAO Ming QI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第8期610-615,共6页
Objective: Leber's hereditary optic neuropathy (LHON) is a maternally inherited degeneration of the optic nerve caused by point mutations of mitochondrial DNA (mtDNA). Many unsolved questions regarding the penet... Objective: Leber's hereditary optic neuropathy (LHON) is a maternally inherited degeneration of the optic nerve caused by point mutations of mitochondrial DNA (mtDNA). Many unsolved questions regarding the penetrance and pathophysiological mechanism of LHON demand efficient and reliable mutation testing. This study aims to develop a minor groove binder (MGB) probe assay for rapid detection of mtDNA11778 mutation and heteroplasmy in Chinese LHON patients by real-time polymerase chain reaction (PCR). Methods: Forty-eight patients suspected of having LHON and their maternal relatives underwent a molecular genetic evaluation, with 20 normal individuals as a control group at the same time. A real-time PCR involving two MGB probes was used to detect the mtDNA 1 1778 mutation and heteroplasmy. A linear standard curve was obtained by pUCmLHONG and pUCmLHONA clones. Results: All 48 LHON patients and their maternal relatives were positive for rntDNA11778 mutation in our assay, 27 heteroplasmic and 21 homoplasmic. Eighteen cases did not show an occurrence of the disease, while 9 developed the disease among the 27 heteroplasmic mutation cases. Eleven did not show an occurrence of the disease, while 10 cases developed the disease among 21 homoplasmic mutation cases. There was a significant difference in the incidence between the heteroplasmic and the homoplasmic mutation types. The time needed for running a real-time PCR assay was only 80 min. Conclusion: This real-time PCR assay is a rapid, reliable method for mtDNA mutation detection as well as heteroplasmy quantification. Detecting this ratio is very important for predicting phenotypic expression of unaffected carriers. 展开更多
关键词 Leber's hereditary optic neuropathy (L HON) Mitochondrial DNA (mtDNA) MtDNA 11778 mutation Minor groove binder (MGB) orobe. Real-time oolvmerase chain reaction (PCR)
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Extracting invariable fault features of rotating machines with multi-ICA networks 被引量:1
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作者 焦卫东 杨世锡 吴昭同 《Journal of Zhejiang University Science》 EI CSCD 2003年第5期595-601,共7页
This paper proposes novel multi-layer neural networks based on Independent Component Analysis for feature extraction of fault modes. By the use of ICA, invariable features embedded in multi-channel vibration measureme... This paper proposes novel multi-layer neural networks based on Independent Component Analysis for feature extraction of fault modes. By the use of ICA, invariable features embedded in multi-channel vibration measurements under different operating conditions (rotating speed and/or load) can be captured together.Thus, stable MLP classifiers insensitive to the variation of operation conditions are constructed. The successful results achieved by selected experiments indicate great potential of ICA in health condition monitoring of rotating machines. 展开更多
关键词 Independent Component Analysis (ICA) Mutual Inform ation (MI) Principal Component Analysis (PCA) Multi-Layer Perceptron (MLP) R esidual Total Correlation (RTC)
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Charge transport in conducting polyaniline co-doped with sulfosalicylic acid and dodecylbenzoyl sulfonic acid
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作者 马利 《Journal of Chongqing University》 CAS 2009年第3期170-174,共5页
We prepared conducting polyaniline (PAn) co-doped with sulfosalicylic acid (SSA) and dodecylbenzoyl sultonic acid (DBSA) in micro-emulsive polymerization, and studied its charge transport behaviors based on the ... We prepared conducting polyaniline (PAn) co-doped with sulfosalicylic acid (SSA) and dodecylbenzoyl sultonic acid (DBSA) in micro-emulsive polymerization, and studied its charge transport behaviors based on the measurement of its electrical conductivity in the temperature range between 203 K and 298 K. The conductivity was found to increase with temperature, similar to the case in semiconductors. Analyzing the experimental data with three models, namely the charge-energy-limitedtunneling model, Kivelson model and the three-dimensional variable range hopping (3D-VRH) model demonstrated that these models all describe well the charge transport behaviors of PAn co-doped with SSA and DBSA within the mentioned temperature range. From calculation with the 3D-VRH model, the hopping distance of the conducting PAn is obviously larger than its localization length. The PAn doped with SSA and DBSA enjoys desirable crystallinity due to the co-doping of two functional sulfonic acids. The macroscopic conductivity may correspond to three-dimensional transport in the network of the bundles, and the metallic islands may be attributed to quasi-one-dimensional bundles. 展开更多
关键词 conducting polymer conductive materials DOPING POLYANILINE charge transport variable range hopping
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