检索结果-南通市图书馆

Cryptic diversity and rampant hybridization in annual gentians on the Qinghai-Tibet Plateau revealed by population genomic analysis

引用

Plant Diversity 2024年第2期46卷 194-205页

作者： Peng-cheng Fu Qiao-Qiao Guo Di Chang Qing-Bo Gao shan-shan Sun School of Life Science Luoyang Normal UniversityLuoyang 471934PR China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001PR China

Understanding the evolutionary and ecological processes involved in population differentiation and speciation provides critical insights into biodiversity formation. In this study, we employed 29,865 single nucleotide polymorphisms(SNPs) and complete plastomes to examine genomic divergence and hybridization in Gentiana aristata, which is endemic to the Qinghai-Tibet Plateau(QTP) region. Genetic clustering revealed that G. aristata is characterized by geographic genetic structures with five clusters(West, East, Central, South and North). The West cluster has a specific morphological character(i.e., blue corolla) and higher values of FSTcompared to the remaining clusters, likely the result of the geological barrier formed by the Yangtze River. The West cluster diverged from the other clusters in the Early Pliocene;these remaining clusters diverged from one another in the Early Quaternary. Phylogenetic reconstructions based on SNPs and plastid data revealed substantial cyto-nuclear conflicts. Genetic clustering and D-statistics demonstrated rampant hybridization between the Central and North clusters,along the Bayankala Mountains, which form the geological barrier between the Central and North clusters. Species distribution modeling demonstrated the range of G. aristata expanded since the Last Interglacial period. Our findings provide genetic and morphological evidence of cryptic diversity in G. aristata, and identified rampant hybridization between genetic clusters along a geological *** findings suggest that geological barriers and climatic fluctuations have an important role in triggering diversification as well as hybridization, indicating that cryptic diversity and hybridization are essential factors in biodiversity formation within the QTP region.

关键词： Gentiana aristata Hybrid zone Qinghai-Tibet Plateau Plastome Nuclear SNPs

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A method for extracting the preseismic gravity anomalies over the Tibetan Plateau based on the maximum shear strain using GRACE data

引用

Earth and Planetary Physics 2024年第4期8卷 589-608页

作者： Hui wang DongMei Song XinJian shan Bin wang College of Oceanography and Space Informatics China University of Petroleum(East China)Qingdao 266580China PCI Technology Group Co. Ltd.Guangzhou 510660China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266200China State Key Laboratory of Earthquake Dynamics Beijing 100029China

The occurrence of earthquakes is closely related to the crustal geotectonic movement and the migration of mass,which consequently cause changes in *** Gravity Recovery And Climate Experiment(GRACE)satellite data can be used to detect gravity changes associated with large ***,previous GRACE satellite-based seismic gravity-change studies have focused more on coseismic gravity changes than on preseismic gravity ***,the noise of the north–south stripe in GRACE data is difficult to eliminate,thereby resulting in the loss of some gravity information related to tectonic *** explore the preseismic gravity anomalies in a more refined way,we first propose a method of characterizing gravity variation based on the maximum shear strain of gravity,inspired by the concept of crustal *** offset index method is then adopted to describe the gravity anomalies,and the spatial and temporal characteristics of gravity anomalies before earthquakes are analyzed at the scales of the fault zone and plate,*** this work,experiments are carried out on the Tibetan Plateau and its surrounding areas,and the following findings are obtained:First,from the observation scale of the fault zone,we detect the occurrence of large-area gravity anomalies near the epicenter,oftentimes about half a year before an earthquake,and these anomalies were distributed along the fault ***,from the observation scale of the plate,we find that when an earthquake occurred on the Tibetan Plateau,a large number of gravity anomalies also occurred at the boundary of the Tibetan Plateau and the Indian ***,the aforementioned experiments confirm that the proposed method can successfully capture the preseismic gravity anomalies of large earthquakes with a magnitude of less than 8,which suggests a new idea for the application of gravity satellite data to earthquake research.

关键词： Gravity Recovery And Climate Experiment(GRACE)data maximum shear strain offset index K preseismic gravity anomalies Tibetan Plateau fault zone

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Decentralized Primary Frequency Regulation for Hybrid Multi-terminal Direct Current Power Systems Considering Multi-source Enhancement

引用

Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 958-970页

作者： Jialiang Wu Zhen wang Ruixu Liu Yu shan Chenxuan wang the College of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China

Hybrid multi-terminal direct current(MTDC)transmission technology has been a research focus,and primary frequency regulation(FR)improvement in the receiving-end system is one of the problems to be *** paper presents a decentralized primary FR scheme for hybrid MTDC power systems considering multi-source enhancement to help suppress frequency disturbance in the receiving-end *** the converters only need local frequency or DC voltage signal input to respond to system disturbance without communication or a control center,i.e.,a decentralized control *** proposed scheme can activate appropriate power sources to assist in FR in various system disturbance severities with fine-designed thresholds,ensuring sufficient utilization of each power *** better balance FR performance and FR resource participation,an evaluation index is proposed and the parameter optimization problem is further ***,the validity of the proposed scheme is verified by simulations in MATLAB/Simulink.

关键词： Decentralized control scheme primary frequency regulation(FR) rate of change of frequency(ROCOF) system frequency disturbance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Triple reverse order law for the Drazin inverse

引用

Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： wang Hua ZHONG cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation ***,the Drazin invertibility of sum is also obtained for two bounded linear operators and... 详细信息

关键词： Drazin inverse reverse order law space decomposition

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhancing Low-Frequency Microwave Absorption Through Structural Polarization Modulation of MXenes

引用

Nano-Micro Letters 2024年第10期16卷 435-452页

作者： Bo shan Yang wang Xinyi Ji Yi Huang College of Light Industry Science and Engineering State Key Laboratory of Biobased Fiber Manufacturing TechnologyTianjin University of Science and TechnologyTianjin 300457People's Republic of China National Institute for Advanced Materials Tianjin Key Laboratory of Metal and Molecule Based Material ChemistryKey Laboratory of Functional Polymer MaterialsCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)School of Materials Science and EngineeringNankai UniversityTianjin 300350People's Republic of China

Two-dimensional carbon-based materials have shown promising electromagnetic wave absorption capabilities in mid-and high-frequency ranges,but face challenges in low-frequency absorption due to limited control over polarization response mecha-nisms and ambiguous resonance *** this study,we pro-pose a novel approach to enhance absorption efficiency in aligned three-dimensional(3D)MXene/CNF(cellulose nanofibers)cavities by modifying polarization properties and manipulating resonance response in the 3D MXene *** controlled polarization mechanism results in a significant shift of the main absorption region from the X-band to the S-band,leading to a remarkable reflection loss value of-47.9 dB in the low-frequency ***,our findings revealed the importance of the oriented electromagnetic coupling in influencing electromagnetic response and microwave absorption *** present study inspired us to develop a generic strategy for low-frequency tuned absorption in the absence of magnetic element participation,while orientation-induced polarization and the derived magnetic resonance coupling are the key controlling factors of the method.

关键词： Hierarchical structure MXene Microwave absorption Low-frequency

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhanced visible light absorption of Bi_(2)WO_(6)/SiO_(2) with abundant adsorbed oxygen for the degradation of organic pollutant

引用

Particuology 2024年第5期88卷 210-217页

作者： Yuanting Wu Xiaoying wang Wenlong Zhong shan Zhang School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China

Heterogeneous photocatalysts exhibit high catalytic efficiency in the degradation of pollutants,but their stability and repeatability is not very good and requires high structural *** by nanosizing the pure Bi_(2)WO_(6)(BWO)photocatalyst without constructing a heterojunction,there is a significant improvement in its performance,with an enhancement effect of about 2.3 times(99.43%).The high photocatalytic degradation efficiency of the material can be attributed to the enhanced light absorption effect brought by the three-dimensional inverse-opal structure SiO_(2)(IS)and the abundant surface adsorbed oxygen generated after the formation of Si–O–W *** addition,the introduction of IS greatly increases the surface area of nanostructured BWO,which accelerates the charge transfer process,while the adsorbed oxygen promotes the participation of·O^(2−) in the photocatalytic reaction,thereby accelerating the consumption of photo-generated electrons and ultimately improving the separation of charge ***,the matched photonic bandgap further improves the absorption and utilization of light of the *** this work,we constructs Si–O–W bonds to obtain inverse-opal SiO_(2)/Bi_(2)WO_(6) with uniformly growth of pure phase nano BWO,which provides a feasible strategy for the preparation of high-performance pure-phase photocatalysts.

关键词： Bi_(2)WO_(6) SiO_(2) inverse-opal structure Photocatalysis Adsorbed oxygen

来源：

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

双重故障模式下基于证据理论和功能组分解的N-k事故辨识方法

引用

中国电机工程学报 2008年第28期28卷 47-53页

作者：宋毅王成山电力系统仿真控制教育部重点实验室(天津大学)

根据不同阶段的特点,连锁故障可以分解为源发性故障阶段和相继故障阶段。该文分析了不同类型的保护装置隐性故障在源发性故障阶段的故障后果,指出断路器失灵故障在连锁故障研究中的重要性,提出一种由源发性故障和断路器失灵故障组成的... 详细信息

根据不同阶段的特点,连锁故障可以分解为源发性故障阶段和相继故障阶段。该文分析了不同类型的保护装置隐性故障在源发性故障阶段的故障后果,指出断路器失灵故障在连锁故障研究中的重要性,提出一种由源发性故障和断路器失灵故障组成的双重故障模式,并基于证据理论和功能组分解思想,给出了该故障模式下的N-k事故辨识方法。算例分析表明,双重故障模式下的N-k事故辨识与源发性故障、故障断路器以及相关母线的接线方式有关,而变电站发电厂主接线对N-1事故扩大为N-k事故有直接影响。

关键词：连锁故障源发性故障相继故障证据理论功能组分解 N-k事故辨识

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

考虑时间延迟影响的电力系统稳定器设计

引用

中国电机工程学报 2007年第10期27卷 1-6页

作者：王成山石颉天津大学电气与自动化工程学院天津市南开区300072 天津大学电气与自动化工程学院

采用广域信息可有效地提高大型互联系统的动态性能。由于距离远,信号传输的时间延迟不可忽略,而时延的存在对电力系统稳定器(PSS)的性能有很大的影响。该文提出了一种考虑时延影响设计PSS的方法。该方法根据留数矩阵确定PSS控制回路;采... 详细信息

采用广域信息可有效地提高大型互联系统的动态性能。由于距离远,信号传输的时间延迟不可忽略,而时延的存在对电力系统稳定器(PSS)的性能有很大的影响。该文提出了一种考虑时延影响设计PSS的方法。该方法根据留数矩阵确定PSS控制回路;采用Pade逼近法近似时间延迟,并写成状态空间形式,与PSS一同形成了时延控制器,同时使系统变为不显含时延项的控制系统;再应用进化策略整定PSS参数。文章以4机系统为例,比较了考虑时延与不考虑时延设计的PSS的性能,说明了该方法的有效性。

关键词：广域信息时间延迟电力系统稳定器 Pade逼近进化策略

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Multimodal Social Media Fake News Detection Based on Similarity Inference and Adversarial Networks

引用

Computers, Materials & Continua 2024年第4期79卷 581-605页

作者： Fangfang shan Huifang Sun Mengyi wang College of Computer Zhongyuan University of TechnologyZhengzhou450007China Henan Key Laboratory of Cyberspace Situation Awareness Zhengzhou 450001China

As social networks become increasingly complex, contemporary fake news often includes textual descriptionsof events accompanied by corresponding images or videos. Fake news in multiple modalities is more likely tocreate a misleading perception among users. While early research primarily focused on text-based features forfake news detection mechanisms, there has been relatively limited exploration of learning shared representationsin multimodal (text and visual) contexts. To address these limitations, this paper introduces a multimodal modelfor detecting fake news, which relies on similarity reasoning and adversarial networks. The model employsBidirectional Encoder Representation from Transformers (BERT) and Text Convolutional Neural Network (Text-CNN) for extracting textual features while utilizing the pre-trained Visual Geometry Group 19-layer (VGG-19) toextract visual features. Subsequently, the model establishes similarity representations between the textual featuresextracted by Text-CNN and visual features through similarity learning and reasoning. Finally, these features arefused to enhance the accuracy of fake news detection, and adversarial networks have been employed to investigatethe relationship between fake news and events. This paper validates the proposed model using publicly availablemultimodal datasets from Weibo and Twitter. Experimental results demonstrate that our proposed approachachieves superior performance on Twitter, with an accuracy of 86%, surpassing traditional unimodalmodalmodelsand existing multimodal models. In contrast, the overall better performance of our model on the Weibo datasetsurpasses the benchmark models across multiple metrics. The application of similarity reasoning and adversarialnetworks in multimodal fake news detection significantly enhances detection effectiveness in this paper. However,current research is limited to the fusion of only text and image modalities. Future research directions should aimto further integrate f

关键词： Fake news detection attention mechanism image-text similarity multimodal feature fusion

来源：

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

Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

引用

Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng wang Xiaoqi wang Shuiyuan cheng Jiaxian Zhu Xinyu Zhang Long cheng Kai wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in *** estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research ***,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was ***,priority control routes for VOC emission sources were proposed for different *** VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main *** protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and *** in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in *** addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：