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Gapless Genome Assembly of ZH8015 and Preliminary Multi-Omics Analysis to Investigate ZH8015's Responses Against Brown Planthopper Infestation
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作者 LI Dian DUAN Wenjing +5 位作者 LIU Qun’en WU Weixun ZHAN Xiaodeng SUN Lianping ZHANG Yingxin CHENG Shihua 《Rice science》 SCIE CSCD 2024年第3期317-327,I0042-I0045,共15页
Accurate genomic information is essential for advancing genetic breeding research in specific rice varieties.This study presented a gapless genome assembly of the indica rice cultivar Zhonghui 8015(ZH8015)using Pac Bi... Accurate genomic information is essential for advancing genetic breeding research in specific rice varieties.This study presented a gapless genome assembly of the indica rice cultivar Zhonghui 8015(ZH8015)using Pac Bio HiFi,Hi-C,and ONT(Oxford Nanopore Technologies)ultra-long sequencing technologies,annotating 43037 gene structures.Subsequently,utilizing this genome along with transcriptomic and metabolomic techniques,we explored ZH8015's response to brown planthopper(BPH)infestation.Continuous transcriptomic sampling indicated significant changes in gene expression levels around 48 h after BPH feeding.Enrichment analysis revealed particularly significant alterations in genes related to reactive oxygen species scavenging and cell wall formation.Metabolomic results demonstrated marked increases in levels of several monosaccharides,which are components of the cell wall and dramatic changes in flavonoid contents.Omics association analysis identified differentially expressed genes associated with key metabolites,shedding light on ZH8015's response to BPH infestation.In summary,this study constructed a reliable genome sequence resource for ZH8015,and the preliminary multi-omics results will guide future insect-resistant breeding research. 展开更多
关键词 brown planthopper gapless genome genome assembly multi-omics Nilaparvata lugens rice
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Spin gapless armchair graphene nanoribbons under magnetic field and uniaxial strain
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作者 侯海平 谢月娥 +3 位作者 陈元平 欧阳滔 葛青霞 钟建新 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期596-600,共5页
Using Green's function method, we investigate the spin transport properties of armchair graphene nanoribbons (AG- NRs) under magnetic field and uniaxial strain. Our results show that it is very difficult to transfo... Using Green's function method, we investigate the spin transport properties of armchair graphene nanoribbons (AG- NRs) under magnetic field and uniaxial strain. Our results show that it is very difficult to transform narrow AGNRs directly from semiconductor to spin gapless semiconductors (SGS) by applying magnetic fields. However, as a uniaxial strain is exerted on the nanoribbons, the AGNRs can transform to SGS by a small magnetic field. The combination mode be- tween magnetic field and uniaxial strain displays a nonmonotonic arch-pattern relationship. In addition, we find that the combination mode is associated with the widths of nanoribbons, which exhibits group behaviors. 展开更多
关键词 GRAPHENE spin gapless spin transport TIGHT-BINDING
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Theoretical description of electron-phonon Fock space for gapless and gapped nanowires
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作者 Ashrafalsadat Shariati Hassan Rabani Mohammad Mardaani 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第3期404-409,共6页
We study the effect of electron-phonon (e-ph) interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The... We study the effect of electron-phonon (e-ph) interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The model is constructed using Green's function and multi-channel techniques, taking into account the local and nonlocal e-ph interactions. Then, we examine the model for the gapless (simple chain) and gapped (PA-like nanowire) systems. The results show that the tunneling conductance is improved by the e-ph interaction in both local and nonlocal regimes, while for the resonance conductance, the coherent part mainly decreases and the incoherent part increases. At the corresponding energies which depend on the phonon frequency, two dips in the elastic and two peaks in the inelastic conductance spectra appear. The reason is the absorption of the phonon by the electron in transition into inelastic channels. 展开更多
关键词 Theoretical description of electron phonon Fock space for gapless and gapped nanowires
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Three-Dirac-fermion approach to unexpected universal gapless surface states in van der Waals magnetic topological insulators 被引量:2
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作者 Dinghui Wang Huaiqiang Wang +1 位作者 Dingyu Xing Haijun Zhang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2023年第9期79-85,共7页
Layered van der Waals(vdW) topological materials, especially the recently discovered MnBi_(2)Te_(4)-family magnetic topological insulators(TIs), have aroused great attention. However, there has been a serious debate a... Layered van der Waals(vdW) topological materials, especially the recently discovered MnBi_(2)Te_(4)-family magnetic topological insulators(TIs), have aroused great attention. However, there has been a serious debate about whether the surface states are gapped or gapless for antiferromagnetic(AFM) TI MnBi_(2)Te_(4), which is crucial to the prospect of various magnetic topological phenomena. Here, a minimal three-Dirac-fermion approach is developed to generally describe topological surface states of nonmagnetic/magnetic vdW TIs under the modulation of the interlayer vdW gap. In particular, this approach is applied to address the controversial issues concerning the surface states of vdW AFM TIs. Remarkably, topologically protected gapless Dirac-cone surface states are found to arise due to a small expansion of the interlayer vdW gap on the surface, when the Chern number equals zero for the surface ferromagnetic layer;while the surface states remain gapped in all other cases. These results are further confirmed by our first-principles calculations on AFM TI MnBi_(2)Te_(4). The theorectically discovered gapless Dirac-cone states provide a unique mechanism for understanding the puzzle of the experimentally observed gapless surface states in MnBi_(2)Te_(4).This work also provides a promising way for experiments to realize the intrinsic magnetic quantum anomalous Hall efect in MnBi_(2)Te_(4) films with a large energy gap. 展开更多
关键词 magnetic topological insulator van der Waals gap Dirac-fermion model gapless surface state
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Investigation of Acoustomagnetoelectric Effect in Bandgap Graphene by the Boltzmann Transport Equation
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作者 Raymond Edziah Samuel S. Bentsiefi +6 位作者 Kwadwo Dompreh Anthony Twum Emmanuel Kofi Amewode Patrick Mensah-Amoah Ebenezer T. Tatchie Cynthia Jebuni-Adanu Samuel Y. Mensah 《World Journal of Condensed Matter Physics》 CAS 2024年第1期10-20,共11页
We study the acoustomagnetoelectric (AME) effect in two-dimensional graphene with an energy bandgap using the semiclassical Boltzmann transport equation within the hypersound regime, (where represents the acoustic wav... We study the acoustomagnetoelectric (AME) effect in two-dimensional graphene with an energy bandgap using the semiclassical Boltzmann transport equation within the hypersound regime, (where represents the acoustic wavenumber and is the mean free path of the electron). The Boltzmann transport equation and other relevant equations were solved analytically to obtain an expression for the AME current density, consisting of longitudinal and Hall components. Our numerical results indicate that both components of the AME current densities display oscillatory behaviour. Furthermore, geometric resonances and Weiss oscillations were each defined using the relationship between the current density and Surface Acoustic Wave (SAW) frequency and the inverse of the applied magnetic field, respectively. Our results show that the AME current density of bandgap graphene, which can be controlled to suit a particular electronic device application, is smaller than that of (gapless) graphene and is therefore, more suited for nanophotonic device applications. 展开更多
关键词 Boltzmann Transport Equation Acoustomagnetoelctric Effect Surface Acoustic Wave gapless Graphene Weiss Oscillations
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Gapless indica rice genome reveals synergistic contributions of active transposable elements and segmental duplications to rice genome evolution 被引量:13
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作者 Kui Li Wenkai Jiang +5 位作者 Yuanyuan Hui Mengjuan Kong Li-Ying Feng Li-Zhi Gao Pengfu Li Shan Lu 《Molecular Plant》 SCIE CAS CSCD 2021年第10期1745-1756,共12页
The ultimate goal of genome assembly is a high-accuracy gapless genome.Here,we report a new assembly pipeline that is used to produce a gapless genome for the indica rice cultivar Minghui 63.The resulting 397.71-Mb fi... The ultimate goal of genome assembly is a high-accuracy gapless genome.Here,we report a new assembly pipeline that is used to produce a gapless genome for the indica rice cultivar Minghui 63.The resulting 397.71-Mb final assembly is composed of 12 contigs with a contig N50 size of 31.93 Mb.Each chromosome is represented by a single contig and the genomic sequences of all chromosomes are gapless.Quality evaluation of this gapless genome assembly showed that gene regions in our assembly have the highest completeness compared with the other 15 reported high-quality rice genomes.Further comparison with the japonica rice genome revealed that the gapless indica genome assembly contains more transposable elements(TEs)and segmental duplications(SDs),the latter of which produce many duplicated genes that can affect agronomic traits through dose effect or sub-/neo-functionalization.The insertion of TEs can also affect the expression of duplicated genes,which may drive the evolution of these genes.Furthermore,we found the expansion of nucleotide-binding site with leucine-rich repeat disease-resistance genes and cis-zeatin-O-glucosyltransferase growth-related genes in SDs in the gapless indica genome assembly,suggesting that SDs contribute to the adaptive evolution of rice disease resistance and developmental processes.Collectively,our findings suggest that active TEs and SDs synergistically contribute to rice genome evolution. 展开更多
关键词 EVOLUTION gapless GENOME rice segmental duplications transposable elements
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Gapless spin-liquid ground state in the S=1/2 kagome antiferromagnet 被引量:5
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作者 Xiang Tao (向涛) Bruce Normand 《Science Foundation in China》 CAS 2017年第3期42-42,共1页
Subject Code:A04Frustrated quantum magnets have developed into one of the hottest topics in condensed matter physics because of the wide range of novel physical phenomena they exhibit,which includes quantum spin-liqui... Subject Code:A04Frustrated quantum magnets have developed into one of the hottest topics in condensed matter physics because of the wide range of novel physical phenomena they exhibit,which includes quantum spin-liquid states,fractionalized spin degrees of freedom,and exotic topological properties.This trend is 展开更多
关键词 gapless spin-liquid ground state in the S APS TRG
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磨削高精度薄壁气缸套座圈及端面用夹具设计
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作者 章祥宝 张建宇 +4 位作者 吕俊杰 董博 张文斗 王婷 赵方毅 《内燃机与配件》 2024年第15期64-66,共3页
针对薄壁气缸套精加工座圈及端面时定位精度低、装夹变形,造成的座圈尺寸形位公差超差问题,通过设计制造一种适合的夹具,在保证使用安全、方便操作的情况下,更好地解决气缸套装夹变形问题,保证某型号发动机高精度薄壁气缸套座圈及端面... 针对薄壁气缸套精加工座圈及端面时定位精度低、装夹变形,造成的座圈尺寸形位公差超差问题,通过设计制造一种适合的夹具,在保证使用安全、方便操作的情况下,更好地解决气缸套装夹变形问题,保证某型号发动机高精度薄壁气缸套座圈及端面的加工精度和加工稳定性要求。 展开更多
关键词 座圈 磨削 装夹变形 无间隙配合
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一起500kV变电站避雷器异常发热分析
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作者 谭超 陈上豪 《科学技术创新》 2024年第22期81-84,共4页
在电力系统中,避雷器是保护设备免受雷电过电压和操作过电压损害的重要设备。其中,500 kV变电站所使用的无间隙金属氧化物避雷器在运行过程中出现异常发热现象,严重影响了设备的正常运行和电网的安全。本文通过对一起500 kV变电站无间... 在电力系统中,避雷器是保护设备免受雷电过电压和操作过电压损害的重要设备。其中,500 kV变电站所使用的无间隙金属氧化物避雷器在运行过程中出现异常发热现象,严重影响了设备的正常运行和电网的安全。本文通过对一起500 kV变电站无间隙金属氧化物避雷器异常发热的案例分析,探讨了发热的原因,并提出了相应的处理措施和防范策略。 展开更多
关键词 500 kV变电站 无间隙金属氧化物避雷器 异常发热 带电检测
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A high-quality genome of Actinidia eriantha provides new insight into ascorbic acid regulation
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作者 LIAO Guang-lian HUANG Chun-hui +4 位作者 JIA Dong-feng ZHONG Min TAO Jun-jie QU Xue-yan XU Xiao-biao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第11期3244-3255,共12页
Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecula... Actinidia eriantha is one of the species of kiwifruit with a particularly high ascorbic acid (AsA) content.However, the molecular mechanism driving AsA richness in fruit remains unclear.In order to reveal the molecular mechanism of AsA richness in A. eriantha, this study constructed a regulatory network related to AsA metabolism by combining genomics,metabolomics and transcriptomics.We assembled a high-quality genome of A. eriantha ‘Ganlv 1’ with only five remaining gaps.The assembly is comprised of 29 pseudochromosomes with a total size of 615.95 Mb, and contig N50 of 20.35 Mb.Among them,24 of the pseudochromosomes were obtained directly from telomere-to-telomere.The LTR assembly index score and consensus quality value were 21.34 and 39.90%, respectively.Subsequently, 61 metabolites and 2 092genes were found to be differentially accumulated/expressed during fruit development by metabolome and transcriptome assays, respectively.AsA metabolism and the cyclic regeneration pathway were found to have high expression levels throughout fruit growth and development,suggesting its crucial role in the regulation of AsA.Furthermore,the AsA contents are highly associated with ascorbate peroxidase genes.The genome obtained in this study provides genomic resources for the genetic and breeding research ofA. eriantha, and the constructed regulatory network can provide a public data platform for future research on kiwifruit. 展开更多
关键词 Actinidia eriantha ascorbic acid non-targeted metabolome gapless genome TRANSCRIPTOME
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短波红外成像技术及其军事应用 被引量:39
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作者 蔡毅 胡旭 《红外与激光工程》 EI CSCD 北大核心 2006年第6期643-647,共5页
短波红外可以提供可见光、微光夜视、中波、长波红外所不能提供的信息。实现短波红外成像,填补微光夜视和中波红外成像之间的光谱空缺,实现在三个大气红外透射窗口的“无缝隙探测,”对在红外波段全面获取目标的信息具有重要意义,可应用... 短波红外可以提供可见光、微光夜视、中波、长波红外所不能提供的信息。实现短波红外成像,填补微光夜视和中波红外成像之间的光谱空缺,实现在三个大气红外透射窗口的“无缝隙探测,”对在红外波段全面获取目标的信息具有重要意义,可应用于夜视、侦察与监视、遥感、遥感系统、红外成像制导、光电对抗等领域。 展开更多
关键词 短波红外 红外成像 无缝隙探测
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坡度对长大坡道桥上无缝道岔的影响分析 被引量:13
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作者 颜乐 熊震威 +1 位作者 魏贤奎 王平 《铁道标准设计》 北大核心 2013年第9期33-36,共4页
为探讨制动工况下,坡度对长大坡道桥上无缝道岔受力与变形的影响,以国内某一坡度为17.2‰新建铁路线上的桥上无缝道岔为例建立力学分析模型,运用"等效轮轨黏着系数",建立了有砟轨道"岔-桥-墩"相互作用的一体化模型... 为探讨制动工况下,坡度对长大坡道桥上无缝道岔受力与变形的影响,以国内某一坡度为17.2‰新建铁路线上的桥上无缝道岔为例建立力学分析模型,运用"等效轮轨黏着系数",建立了有砟轨道"岔-桥-墩"相互作用的一体化模型,分析不同坡度下列车制动时,钢轨纵向力、钢轨位移、墩台纵向力、心轨和尖轨位移以及间隔铁纵向力的变化。分析结果表明:坡度的增大对桥上无缝道岔的受力与变形都是不利的;侧股间隔铁的纵向力比直股间隔铁小,但是其受坡度的影响却较大;长大坡道上容易产生爬行现象,应加强无缝道岔防爬锁定,并加密防爬观测次数。 展开更多
关键词 坡度 长大坡道 桥上无缝道岔 制动
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大功率电力电子装置过电压保护技术综述 被引量:7
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作者 蓝元良 印永华 周孝信 《电力电子技术》 CSCD 北大核心 2005年第3期123-125,共3页
概要回顾和比较了几种常用于电力系统高压装置中的传统过电压保护设备如保护间隙、阀型避雷器和无间隙氧化锌避雷器等;简单叙述了无间隙氧化锌避雷器和晶闸管各自的过电压保护特点。在了解国内外一些大功率电力电子装置如直流输电装置... 概要回顾和比较了几种常用于电力系统高压装置中的传统过电压保护设备如保护间隙、阀型避雷器和无间隙氧化锌避雷器等;简单叙述了无间隙氧化锌避雷器和晶闸管各自的过电压保护特点。在了解国内外一些大功率电力电子装置如直流输电装置、静止无功补偿装置、可控串联补偿装置等过电压保护技术发展现状的基础上,从电力电子装置本身的过电压保护技术,用电力电子技术对其他设备进行过电压保护两个方面,论述了当今大功率电力电子装置过电压保护的一些措施及其分类。最后,对大功率电力电子装置过电压保护技术进行总结和展望。 展开更多
关键词 晶闸管 无间隙避雷器 金属氧化物避雷器 过电压保护/大功率电力电子装置
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大气PM2.5遥感制图研究进展 被引量:15
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作者 沈焕锋 李同文 《测绘学报》 EI CSCD 北大核心 2019年第12期1624-1635,共12页
遥感技术具有时空大范围、低成本的独特优势,已经成为定量监测大气PM2.5污染时空分布的重要手段。本文综述了大气PM2.5遥感制图的进展:首先,对大气PM2.5遥感反演方法进行了归纳,以及总结了现有大气PM2.5遥感反演验证方法的适用条件与局... 遥感技术具有时空大范围、低成本的独特优势,已经成为定量监测大气PM2.5污染时空分布的重要手段。本文综述了大气PM2.5遥感制图的进展:首先,对大气PM2.5遥感反演方法进行了归纳,以及总结了现有大气PM2.5遥感反演验证方法的适用条件与局限性;其次,对卫星反演大气PM2.5合成产品偏差校正和大气PM2.5无缝制图进行了梳理;最后总结了大气PM2.5遥感制图的前沿研究方向。 展开更多
关键词 大气PM2.5制图 卫星遥感 星-地融合 精度验证 无缝监测
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特高压直流线路限制操作过电压用无间隙避雷器的安装方式 被引量:7
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作者 杨博 孙成贤 +2 位作者 王宁宁 孙传政 赵庆周 《电力科学与技术学报》 CAS 北大核心 2021年第4期188-195,共8页
当前架空输电线路主要安装限制雷电过电压避雷器,限制操作过电压无间隙避雷器的安装及应用仍是空白,这种避雷器在±1100 kV昌吉—古泉特高压直流输电线路上首次安装,可将全线操作过电压限制在1.5 p.u.以下,从而缩减间隙值、减少杆... 当前架空输电线路主要安装限制雷电过电压避雷器,限制操作过电压无间隙避雷器的安装及应用仍是空白,这种避雷器在±1100 kV昌吉—古泉特高压直流输电线路上首次安装,可将全线操作过电压限制在1.5 p.u.以下,从而缩减间隙值、减少杆塔尺寸及交叉跨越距离,大大节省工程投资。该文提出在线路直线塔和耐张塔上安装避雷器的多种方案;通过对比分析,选用外挑支架悬挂式安装避雷器方案为最佳方案;并在此基础上分析避雷器静、动态荷载,创新设计塔头布置型式、选型引流线及设计连接金具。通过实际工程中的安装和运行,首次验证特高压直流线路安装无间隙避雷器的可行性,为线路安装避雷器提供范例。 展开更多
关键词 无间隙 避雷器 限制操作过电压 特高压直流 直线塔 耐张塔
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动词短语的名词化与饱和关系子句的句法分析 被引量:5
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作者 熊仲儒 刘凡 《华文教学与研究》 CSSCI 2013年第1期70-79,共10页
汉语动词短语可以转类为名词短语,其主要表现是主语或宾语获得属格标记"的",增添了限定范畴,缺失了时制-时体-情态形态与评价性副词修饰等。在缺失属格标记或限定范畴的情况下,由动词短语转类的名词短语取子句形式。饱和关系... 汉语动词短语可以转类为名词短语,其主要表现是主语或宾语获得属格标记"的",增添了限定范畴,缺失了时制-时体-情态形态与评价性副词修饰等。在缺失属格标记或限定范畴的情况下,由动词短语转类的名词短语取子句形式。饱和关系子句是名词短语,而非子句。这不仅使饱和关系子句具有名词短语的属性,也使它跟中心语不能通过空位发生关联。饱和关系子句是其所在的名词性短语的中心语的论元。 展开更多
关键词 动词短语 名词化 饱和关系子句 功能范畴
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直线电机轨道交通的轨道结构 被引量:4
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作者 高亮 郝建芳 《都市快轨交通》 2006年第4期59-61,共3页
对国外直线电机轨道交通主要采用的轨道结构形式进行分析,针对直线电机轨道交通轨道结构形式的力学特点,就我国在发展该种轨道交通时在轨道结构设计与施工中需要研究的关键技术进行初步探讨。
关键词 直线电机 轨道交通 轨道结构 无缝线路 无碴轨道
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城市轨道交通连续梁桥上无缝线路伸缩力计算 被引量:3
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作者 李保友 唐进锋 刘亚敏 《都市快轨交通》 2006年第6期42-45,共4页
在总结既有文献的基础上,分析现场测试数据,根据梁轨相互作用原理,提出一种以边界和变形协调条件为基础来计算城市轨道交通连续梁上伸缩力的模型,解决了采用常量阻力无法得出城市轨道交通长连续梁伸缩力的问题。采用C++语言编程计算。
关键词 桥上无缝线路 伸缩力 连续梁桥 城市轨道交通 模型
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Translohr有轨电车轨道结构 被引量:21
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作者 高江宁 《城市轨道交通研究》 北大核心 2012年第4期98-102,共5页
Translohr新型有轨电车系统已经得到较为广泛的应用。该系统导轨的轨道结构与传统有轨电车的轨道结构有着很大区别。结合上海浦东张江有轨电车工程导轨的轨道结构设计实践,简介了该类有轨电车正线导轨的轨道结构的设计概况,详细介绍了... Translohr新型有轨电车系统已经得到较为广泛的应用。该系统导轨的轨道结构与传统有轨电车的轨道结构有着很大区别。结合上海浦东张江有轨电车工程导轨的轨道结构设计实践,简介了该类有轨电车正线导轨的轨道结构的设计概况,详细介绍了树脂浇注工艺特点和道岔设备特点。 展开更多
关键词 新型有轨电车 Translohr系统 轨道结构 无缝 线路 树脂浇注 道岔
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超声波检测无缝钢轨热应力研究 被引量:4
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作者 孟立凡 王恩怀 齐红丽 《华北工学院学报》 2005年第1期50-52,共3页
 介绍了超声波无损探伤用于无缝钢轨纵向应力的检测,在轨温变化时,超声波在相同长度的钢轨里传递时间随着轨温的变化而变化,而轨温与所检测的无缝钢轨纵向应力成正比,原理可行.其装置的特点是简单,便携,方便使用,便于日常维护使用,不...  介绍了超声波无损探伤用于无缝钢轨纵向应力的检测,在轨温变化时,超声波在相同长度的钢轨里传递时间随着轨温的变化而变化,而轨温与所检测的无缝钢轨纵向应力成正比,原理可行.其装置的特点是简单,便携,方便使用,便于日常维护使用,不受使用时间和地点的限制. 展开更多
关键词 钢轨 无缝 纵向应力 超声波检测 使用时间 无损探伤 原理 热应力 装置
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