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大跨度部分地锚式斜拉桥抗风稳定性参数研究

桥梁建设 2016年第3期46卷 23-28页

作者：张新军姚美浙江工业大学建筑工程学院浙江杭州310014

为了解大跨度部分地锚式斜拉桥的抗风性能,以一座主跨1 400m的部分地锚式斜拉桥方案为背景,采用大跨度桥梁三维非线性抗风稳定性分析方法,将地锚段主梁长度、辅助墩数量、主梁宽度和高度及桥塔高跨比等影响因素对结构自振频率、颤振临... 详细信息

为了解大跨度部分地锚式斜拉桥的抗风性能,以一座主跨1 400m的部分地锚式斜拉桥方案为背景,采用大跨度桥梁三维非线性抗风稳定性分析方法,将地锚段主梁长度、辅助墩数量、主梁宽度和高度及桥塔高跨比等影响因素对结构自振频率、颤振临界风速和跨中处主梁位移的影响进行分析。结果表明:增大地锚段主梁长度、边跨设置辅助墩有利于提高结构自振频率和颤振临界风速,减小跨中处主梁位移,但地锚段主梁长度和辅助墩数量存在最优合理值;增加主梁宽度可以有效提高结构自振频率和颤振临界风速,减小跨中处主梁位移;增加主梁高度可以有效提高结构的颤振临界风速,但对自振频率和跨中处主梁位移影响不大;增加桥塔高度可以有效提高结构自振频率和颤振临界风速,减小跨中处主梁位移。

关键词：部分地锚式斜拉桥抗风稳定性影响因素自振频率颤振临界风速主梁位移

价值判断、问题反思与走出困境——近35年来公众历史教育思想的演进

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四川师范大学学报（社会科学版） 2016年第3期43卷 53-58页

作者：刘开军四川师范大学历史文化与旅游学院成都610066

近35年来,有关公众历史教育的认识与反思包含了价值判断、问题反思与走出困境三个主要层次。研究者从培养国人、传承文明、认识国家前途等角度衡量公众历史教育的价值,给历史教育赋予了人文情怀和政治担当。面对历史知识传播中史实讹误... 详细信息

近35年来,有关公众历史教育的认识与反思包含了价值判断、问题反思与走出困境三个主要层次。研究者从培养国人、传承文明、认识国家前途等角度衡量公众历史教育的价值,给历史教育赋予了人文情怀和政治担当。面对历史知识传播中史实讹误、史观混乱、语言媚俗、过度追逐利润而忽视教化等问题,史学界开展了深刻的反思与批判,并形成了一些共识:第一,树立公众历史教育的原则,更新传播手段;第二,提高公众历史教育主体的素质,培养专门人才;第三,借鉴国外经验,发展公共史学。今后,有关公众历史教育的批判仍是必要的;各级政府、学术机构、学术团体在公众历史教育中要担负起各自的职责,发挥其应有的作用;公众历史教育要为公众服务,但不能抛弃历史和教育的双重底线;史学工作者与非史学专业出身的从业者需互相学习,取彼之长补己之短,共同推动公众历史教育朝着繁荣、健康的方向发展。

关键词：公众历史教育通俗历史公共史学

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玉米与花生间作的根际互惠方式及其机制

福建农林大学学报（自然科学版） 2019年第4期48卷 409-417页

作者：林伟伟罗晓棉林文雄福建农林大学生命科学学院福建省农业生态过程与安全监控重点实验室福建福州350002

采用两种间作比例(3:8和3:12)和3种种间根系间隔方式(无隔、网隔、全隔)双因素随机试验设计,运用生态位理论与方法,对玉米和花生复合群体的产量、系统生产力(SPI)及根际生态位效益进行分析.结果表明,玉米和花生以3:8和3:12间作在无隔和... 详细信息

采用两种间作比例(3:8和3:12)和3种种间根系间隔方式(无隔、网隔、全隔)双因素随机试验设计,运用生态位理论与方法,对玉米和花生复合群体的产量、系统生产力(SPI)及根际生态位效益进行分析.结果表明,玉米和花生以3:8和3:12间作在无隔和网隔处理下的土地当量比(LeR)均大于1,且3:8间作在无隔和网隔处理下的SPI显著高于3:12间作的相应处理和单作对照.在相同间作比例下,全隔处理的实际产量损失指数(AYL)、区域时间等价率(ATeR)和农田利用效率(LUe)均明显低于无隔和网隔处理.在单作环境下,作物群体占据的营养生态位宽度最窄(Bm=0.0785,Bp=0.0893),重叠度最高(Omp=0.9956);3:8间作的营养生态位宽度和重叠度的变化幅度大于3:12间作.此外,3:8间作的玉米和花生土壤生境生态位适宜度均比3:12间作高,单作最低;3:8和3:12间作在无隔处理下的根系生态位指数显著高于单作、全隔和网隔处理.

关键词：玉米花生间作土地当量比生态位

石墨烯线缺陷的电子valley滤波特性的数值模拟研究

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南京大学学报（自然科学版） 2014年第1期50卷 14-22页

作者：肖灿俊董锦明南京大学物理学院固体微结构国家重点实验室南京210093

基于紧束缚近似哈密顿模型,运用波包动力学方法,数值模拟研究了石墨烯电子穿越线缺陷的输运性质和相应的透射率,着重探讨线缺陷对于电子Valley赝自旋的滤波特性.模拟结果表明:(1)石墨烯线缺陷对于电子valley赝自旋具有半透性;(2)电子的... 详细信息

基于紧束缚近似哈密顿模型,运用波包动力学方法,数值模拟研究了石墨烯电子穿越线缺陷的输运性质和相应的透射率,着重探讨线缺陷对于电子Valley赝自旋的滤波特性.模拟结果表明:(1)石墨烯线缺陷对于电子valley赝自旋具有半透性;(2)电子的透射率与入射角度和能量都有关;(3)在某个临界角度θc,透射率出现峰值,其大小随着能量的增加而增大,而|θc|的绝对值却随能量的增加而减小;(4)当入射角|θ|大于|θc|时,透射率将急剧地降为0.进一步的理论分析指出,这是由于透射率能量关系中的非线性项所造成的.最后,我们的数值模拟结果进一步地证明了石墨烯线缺陷未来作为valley赝自旋滤波器件的实用可能性.

关键词：石墨烯线缺陷 valley滤波波包动力学模拟 KPM方法

Characterization of endophytic Microorganisms of Rice(Oryza sativa L.)Potentials for Blast Disease Biocontrol and Plant Growth Promoting Agents

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Phyton-International Journal of experimental Botany 2023年第11期92卷 3021-3041页

作者： Shugufta Parveen Fayaz A.Mohiddin M.Ashraf Bhat Zahoor Ahmed Baba Fehim Jeelani M.Anwar Bhat Sajad un Nabi Burhan Hamid Saba Bandey Farhanaz Rasool Zakir Amin Ibrahim Al-Ashkar Muhammad Adnan Ayman el Sabagh Division of Plant Pathology Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Mountain Research Centre for Field Crops SKUAST-KashmirKhudwaniIndia Division of Genetics and Plant Breeding Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Division of Microbiology Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Division of Statistics Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Division of Agronomy Faculty of AgricultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirWaduraIndia Indian Council of Agricultural Research-Central institute of Temperate Horticulture(ICAR-CITH) Old AirportRangrethSrinagarIndia Division of Plant Pathology Faculty of HorticultureSher-e-Kashmir University of Agricultural Sciences and Technology of KashmirShalimarIndia Directorate of extension Sher-e-Kashmir University of Agricultural Sciences and Technology of KashmirShalimarIndia Department of Plant Production College of Food and Agriculture SciencesKing Saud UniversityRiyadhSaudi Arabia College of Food Agricultural and Environmental SciencesThe Ohio State UniversityColumbusOHUSA Department of Agronomy Faculty of AgricultureUniversity of KafrelsheikhKafrelsheikhEgypt

One hundred twenty-five endophytic microorganisms were isolated from the roots,stems,and leaves of four prominent rice cultivars growing in temperate *** potential to combat rice blast disease and promote plant growth was *** dual culture tests highlighted the strong antagonistic activity of five fungal(ranging from 89%–70%)and five bacterial(72%–61%)*** examination focused on volatile compounds produced by selected isolates to counter the blast *** these,the highest chitinase(13.76μg mL−1)and siderophore(56.64%),was exhibited by Aspergillus flavus,and the highest HCN production was shown by Stenotrophomonas maltophilia(36.15μM mL−1).In terms of growth promotion traits,Aspergillus flavus and enterobacter cloacae excelled in activities viz,phosphorous solubilization,ammonia production,auxin and gibberellic acid production,and nitrogen *** Identity of these endophytes was confirmed through molecular analysis as Trichoderma afroharzianum,Trichoderma harzianum,Penicillium rubens,Aspergillus flavus,Stenotrophomonas rhizophila,Stenotrophomonas maltophilia,Bacillus cereus,enterobacter cloacae,and Bacillus *** greenhouse conditions,the highest disease control was shown by isolate Bacillus licheniformis and *** with an inhibition of 79%,followed by ***(77%)and ***(73%).The overall results of this study showed that Bacillus licheniformis and Stenotrophomonas rhizophila have great potential to be used as bio-stimulant and biocontrol agents to manage rice blast disease.

关键词： endophytes phylogeny antagonistic activity Pyricularia phytohormones

基于电压偏差向量2-范数的主动配电网故障定位新方法

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电力系统自动化 2015年第15期39卷 96-102页

作者：戴志辉崇志强李川李芷筠华北电力大学电气与电子工程学院河北省保定市071003

随着分布式电源在配电网中渗透率的提高,现有的一些故障定位算法可能失效,对此,提出了一种基于最小电压偏差向量2-范数的故障定位算法。首先,根据配电网各节点注入的等效故障电流计算各电源处电压变化值,并比较各电源处电压变化测量值... 详细信息

随着分布式电源在配电网中渗透率的提高,现有的一些故障定位算法可能失效,对此,提出了一种基于最小电压偏差向量2-范数的故障定位算法。首先,根据配电网各节点注入的等效故障电流计算各电源处电压变化值,并比较各电源处电压变化测量值与电压变化计算值之差,搜索差值向量最小2-范数对应的故障电流注入节点从而确定故障区段的第一个节点,其次,通过该节点两侧电压差值变化确定故障区段的另一节点,实现故障区段定位。最后,利用Ieee 34节点三相不平衡系统进行了故障定位分析,结果表明算法物理意义明确、计算过程简单且具有良好的故障定位准确度。

关键词：故障区段定位配电网分布式发电 2-范数

ReHABILITATION OF A LARGe DAM BY CONSTRUCTION OF eMeRGeNCY SPILLWAY

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REHABILITATION OF A LARGE DAM BY CONSTRUCTION OF EMERGENCY S...

The Construction , expression and Characteristic of Penicillium expansum lipase Mutant P239A

International Symposium on Modern Technology of Dams--The 4th eADC Symposium

作者： Jeon,Tae Myoung Oh,Cheol Gyu Baek,un Il Kim,Chu Hwa Daelim Industrial Co. Ltd.146-12Susong-DongJongno-GuSeoul 110-732Korea Daelim Industrial Co. Ltd.146-12Susong-DongJongno-GuSeoul 110-732Korea Daelim Industrial Co. Ltd.146-12Susong-DongJongno-GuSeoul 110-732Korea Daelim Industrial Co. Ltd.146-12Susong-DongJongno-GuSeoul 110-732Korea

＜正＞Recently unexpected severe rainfall has frequently come due to the climate change. During the last decade,Korea has suffered from extreme floods such as typhoon‘Rusa（2002）’and ‘Maemi（2003）’.The rapid increase of rainfall intensity became a threat to the safety of existing ***,the standard of dam design to cope with the extreme floods has been changed from Frequency Flood to Probable Maximum Flood（PMF）to secure the safety of *** hydrological assessment for the safety of existing dams was conducted by Kwater in 2004 with consideration on the recent extreme *** result of the hydrological assessment shows that the enhancement of the flood control capacity of most of existing large dams is required to prevent disasters from excessive *** measures to enhance the flood control capacity of existing dams are categorized into two ways,i.e.,non-structural and structural *** of dam height and construction of the upper dam or emergency spillway belong to the structural measures. This report mainly introduces the rehabilitation of a large dam by construction of emergency spillway using the case of Imha multipurpose *** enlarge the flood control capacity of Imha dam,a tunnel type emergency spillway was designed according to the newly calculated *** this report,the progress of the project and the detailed design of the spillway are *** the optimized design of the spillway,several considerations were *** primary considerations can be classified as follow. √ Is the location and the type of spillway suitable? √ Is there any damage to the downstream? √ Is the geological features considered enough? √ Is the damage of environment and ecosystem minimized? √ Is the regional culture property considered? Turn-key（design-build bid）on Imha dam emergency spillway was noticed in *** design was completed in 2006 and the spillway is now under construction.

关键词： rehabilitation of a large dam emergency spillway PMP Imha multipurpose dam

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The Construction , Expression and Characteristic of Penicill...

华东六省一市生物化学与分子生物学会2003年学术交流会

作者： LIN Jun-Han, un Lin (Bioengineering college,Fujian Normal university, Fuzhou 350007}

In some industrial application, people need cold-active lipase which has the higher activity in the lower tem-perature. According to three-dimensional structure modeling, we replaced the 239th Pro residues of the lipase withAla residues to imProve its Property by Site-direeted Mutagensis. We hope to obtain the mutant which has a low op-timum *** first, with the application of computer assistant design, we synthesized the mutant primer, and obtain thefull PeL gene lipP239A which contained the mutant site using megaprimer PCR. The second, we ligased lipP239Awith vector pBluescript ⅡSk(+ ) to form recombinant Plamid pSK-PeL-P239A which then was transformed into e.

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“依视路”杯全国法语文学翻译竞赛原文

法语学习 2008年第1期 8-11页

作者： un PRSeNT TeRNeL

Lire , c'est obir à l'injonction des morts . Le texte littraire cependant n'est pas la parole d'un sujet ,aujourd'hui disparu,et qui s'y serait conserve ;lire n'est pas entendre :personne ne parle . Ne

关键词： “依视路”杯中国法语文学翻译竞赛原文文学翻译