检索结果-南通市图书馆

Patterns and drivers of avian taxonomic and phylogenetic beta diversity in China vary across geographical backgrounds and dispersal abilities

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2024年第1期45卷 125-135页

作者： jian-Chao Liang Zhi-Feng Ding Chun-Lin Li Yi-ming Hu Zhi-Xin Zhou Gan-Wen Lie Xiao-Nan Niu Wen-Bin Huang Hui-jian Hu Xing-Feng Si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong 510260China School of Resources and Environmental Engineering Anhui UniversityHefeiAnhui 230601China Guangdong Eco-Engineering Polytechnic GuangzhouGuangdong 510520China Huizhou Institute of Forestry(Huizhou Botanical Garden Management Service Center) HuizhouGuangdong 516001China Administration of National Nature Reserve for Marine Ecology of Guangdong Nanpeng Islands ShantouGuangdong 515900China Zhejiang Zhoushan Archipelago Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity ***,we examined whether the patterns and drivers of taxonomic beta diversity(TBD)and phylogenetic beta diversity(PBD)of breeding birds in China vary across(1)regions on both sides of the Hu Line,which demarcates China’s topographical,climatic,economic,and social patterns,and(2)species with different dispersal *** and PBD were calculated and partitioned into turnover and nestedness components using a moving window *** representing climate,habitat heterogeneity,and habitat quality were employed to evaluate the effects of environmental *** distance was considered to assess the impact of dispersal *** partitioning analysis was applied to assess the relative roles of these *** general,the values of TBD and PBD were high in mountainous areas and were largely determined by environmental ***,different dominant environmental filters on either side of the Hu Line led to divergent beta diversity ***,climate-driven species turnover and habitat heterogeneity-related species nestedness dominated the regions east and west of the line,***,bird species with stronger dispersal ability were more susceptible to environmental filtering,resulting in more homogeneous *** results indicated that regions with distinctive geographical backgrounds may present different ecological factors that lead to divergent assemblage dissimilarity patterns,and dispersal ability determines the response of assemblages to these ecological *** a single universal explanation for the observed pattern without considering these aspects may lead to simplistic or incomplete ***,a comprehensive understanding of large-scale beta diversity patterns and effective pla

关键词： Beta diversity Environmental filtering Dispersal limitation Hu Line Species dispersal ability Breeding birds

Short-term displacement prediction for newly established monitoring slopes based on transfer learning

在线全文

学校读者我要写书评

暂无评论

China Geology 2024年第2期7卷 351-364页

作者： Yuan Tian Yang-landuo Deng ming-zhi Zhang Xiao Pang Rui-ping Ma jian-xue Zhang Institute of Remote Sensing and Geographical Information Systems Peking UniversityBeijing 100871China Beijing Key Laboratory of Spatial Information Integration and Its Applications Beijing 100871China Institute of Public Safety Research Department of Engineering PhysicsTsinghua UniversityBeijing 100084China China Institute of Geo-Environment Monitoring Beijing 100081China Technology Innovation Center for Geohazard Monitoring and Risk Early Warning Ministry of Natural ResourcesBeijing 100081China

This study makes a significant progress in addressing the challenges of short-term slope displacement prediction in the Universal Landslide Monitoring Program,an unprecedented disaster mitigation program in China,where lots of newly established monitoring slopes lack sufficient historical deformation data,making it difficult to extract deformation patterns and provide effective predictions which plays a crucial role in the early warning and forecasting of landslide hazards.A slope displacement prediction method based on transfer learning is therefore ***,the method transfers the deformation patterns learned from slopes with relatively rich deformation data by a pre-trained model based on a multi-slope integrated dataset to newly established monitoring slopes with limited or even no useful data,thus enabling rapid and efficient predictions for these ***,as time goes on and monitoring data accumulates,fine-tuning of the pre-trained model for individual slopes can further improve prediction accuracy,enabling continuous optimization of prediction results.A case study indicates that,after being trained on a multi-slope integrated dataset,the TCN-Transformer model can efficiently serve as a pretrained model for displacement prediction at newly established monitoring *** three-day average RMSE is significantly reduced by 34.6%compared to models trained only on individual slope data,and it also successfully predicts the majority of deformation *** fine-tuned model based on accumulated data on the target newly established monitoring slope further reduced the three-day RMSE by 37.2%,demonstrating a considerable predictive *** conclusion,taking advantage of transfer learning,the proposed slope displacement prediction method effectively utilizes the available data,which enables the rapid deployment and continual refinement of displacement predictions on newly established monitoring slopes.

关键词： Landslide Slope displacement prediction Transfer learning Integrated dataset Transformer Pre-trained model Universal Landslide Monitoring Program(ULMP) Geological hazards survey engineering

Dinitrophenyl-oxadiazole compounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang Cong Li Mou Sun Qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu jian-guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering Group CO. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military composite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole compounds were designed and *** compounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 J,friction sensitivity>360 N).All these compounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectroscopy,elemental *** 2,3 were unambiguously confirmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

An improved analysis method for assessing the nuclear-heating impact on the stability of toroidal field magnets in fusion reactors

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第6期35卷 163-176页

作者： Yu-Dong Lu Jin-Xing Zheng Xu-Feng Liu Huan Wu jian Ge Kun Xu ming Li Hai-Yang Liu Lei Zhu Fei Liu Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin of superconducting magnets during normal operation is the nuclear heating caused by D-T *** study investigates the impact of nuclear heat-ing on a superconducting magnet system by employing an improved analysis method that combines neutronics and thermal *** the magnet system,toroidal field(TF)magnets are positioned closest to the plasma and bear the highest nuclear-heat load,making them prime candidates for evaluating the influence of nuclear heating on *** enhance the modeling accuracy and facilitate design modifications,a parametric TF model that incorporates heterogeneity is established to expedite the optimization design process and enhance the accuracy of the computations.A comparative analysis with a homogeneous TF model reveals that the heterogeneous model improves accuracy by over 12%.Considering factors such as heat load,magnetic-field strength,and cooling conditions,the cooling circuit facing the most severe conditions is selected to calculate the temperature of the *** selection streamlines the workload associated with thermal-hydraulic *** approach enables a more efficient and precise evaluation of the temperature margin of TF ***,it offers insights that can guide the optimization of both the structure and cooling strategy of superconducting magnet systems.

关键词： Superconducting magnet Nuclear heating Neutronics Thermal hydraulics

Interaction mechanism between BaZrO_(3)/Y_(2)O_(3) refractory and Ti_(2)Ni alloy melts

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1376-1388页

作者： Xiao Hou Guang-yao Chen jian Liu ming-rui Lv Fei-hai Yu Qi-sheng Feng Rong-bin Li Xiong-gang Lu Chong-he Li State Key Laboratory of Advanced Special Steel and shanghai Key Laboratory of Advanced Ferromeallurgy and School of Materials Science and Engineering Shanghai UniversityShanghai 200072China shanghai Special Casting Engineering Technology Research Center Shanghai 201605China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314100ZhejiangChina School of Materials Science and Engineering Shanghai DianJi UniversityShanghai 201306China

The titanium alloys with highly chemical activity require stable crucible refractories that can withstand the erosion of alloy *** phase composition and microstructure are crucial factors that affect the stability of the refractory *** effect of Y_(2)O_(3) on the composition and microstructure of BaZrO_(3) crucible was systematically investigated,and the improved mechanism of the stability of BaZrO_(3)/Y_(2)O_(3) crucible was clarified in comparison with the BaZrO_(3) *** results showed that the erosion layer thickness of the BaZrO_(3)/Y_(2)O_(3) crucible was only 63μm,which was far less than that in the BaZrO_(3) crucible(485μm),and the erosion layer in the BaZrO_(3)/Y_(2)O_(3) crucible also exhibited a higher density than that in the BaZrO_(3) *** the sintering,Y_(2)O_(3) could improve the densification of the BaZrO_(3) crucible due to the solid solution effect between Y_(2)O_(3) and ZrO_(2),which also caused the evaporation of BaO,resulting in the generation of a Y_(2)O_(3)(ZrO_(2))film on the surface of the ***,the Y_(2)O_(3)(ZrO_(2))had higher thermodynamic stability than Y_(2)O_(3),confirming that the BaZrO_(3)/Y_(2)O_(3) crucible with high density exhibited a superior erosion resistance to titanium *** dual-phase structure provides a strategy to design a long-life and stable refractory for melting titanium alloys.

关键词： Barium zirconate Yttrium oxide Dual-phase refractory Titanium alloy Interaction

Portable fluorogenic probe for monitoring of volatile amine vapour and food spoilage

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

Chinese Chemical Letters 2024年第3期35卷 257-261页

作者： jian-Hao Zhao Wen-Xing Xu Bin Li Wei Xu Wu-Kun Zhang ming-Shuai Yuan Hui-Zi Li Qing-Guo He Xiang Ma jian-Gong Cheng Yan-Yan Fu State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of the Chinese Academy of SciencesBeijing 100039China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

There are urgent needs of volatile amine gas sensors with high-performance in food quality control,disease monitoring and environmental ***-film fluorescent probe is suitable for amine vapour sensing due to its high sensitivity,high selectivity,and no polluting ***,a novel fluorescent probe based on indacenodithiophene structure withπconjugated system was designed and *** experimental results show that the films prepared by this material exhibit rapid and distinct fluorescence quenching after being exposed to saturated vapours of primary amine,secondary amine and tertiary amine represented by n-propylamine,diethylamine and trimethylamine,*** quenching of fluorescence is 84%,87%and 96%,respectively,within 10 *** detection mechanism of probe for primary amine is based on specific chemical reaction,while the detection mechanism for secondary amine and tertiary amine is intramolecular charge *** experiments show that the detection limit of the fluorescent probe for trimethylamine,an important marker of food spoilage,could reach 4.610 ***-site detection based on spoilage of small yellow croaker suggests the material possesses the potential for food freshness *** simple fluorogenic probe is an original approach to simplify real-time visual monitoring of volatile amine vapour.

关键词： Fluorescent probe Volatile amine Gas sensing Trimethylamine Food spoilage

Enhanced cycling stability and rate performance of Co-doped and La_(2)O_(3)-coated LiNi_(0.9)Mn_(0.1)O_(2) toward power battery

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 658-670页

作者： Jia-Qi Peng Yuan-Yuan Wei Dong-ming Liu Yun Li Bin Hu Bin Huang jian-Wen Yang Shun-Hua Xiao Ren-Heng Wang Guangxi Key Laboratory of Electrochemical and Magneto-Chemical Functional Materials College of Chemistry and BioengineeringGuilin University of TechnologyGuilin541004China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China

Ultra-high nickel layered oxide cathode material with high energy density is the most promising material to improve the electrochemical performance of lithium-ion batteries(LIBs).However,the poor structural stability and severe surface/interface side reactions of the material lead to poor rate performance and cyclic stability,which limits its application in *** this paper,the dual-modification strategy of Co doping and La_(2)O_(3) coating is used to meet the above *** doping can effectively widen layer spacing and reduce Li^(+)/Ni^(2+) mixing,and La_(2)O_(3) coating can effectively eliminate the residual alkali on the surface of active material,inhibit the thickening of cathode electrolyte interphase(CEI)film and reduce surface/interface side ***,the modified material(NM90-CL)with excellent electrochemical properties is achieved through the synergistic enhancement of Co doping and La_(2)O_(3) *** capacity retention rate can reach 77.9%after 200 cycles at 1.0℃ and 75.7%after 200 cycles at 5.0℃.Its reversible capacity can up to 153.5 mAh·g^(–1) at 10.0℃.This dual-modification strategy will provide theoretical guidance and technical support for the synthesis of other high-performance electrode materials.

关键词： High nickel cathode material Co doping La_(2)O_(3) coating Electrochemical performance Electrochemical mechanism

国家的城市及其限度——从政治仪轨到人民至上

在线全文

学校读者我要写书评

暂无评论

理论与改革 2024年第1期 72-84,166页

作者：姚尚建华东政法大学政府管理学院

在城市发展史中,城市参与了现代国家的建构,现代城市从单一的国家权力表征逐步嬗变为资本与社会的空间结果。基于工商业的快速推动,国家对于城市的控制开始松动,城市在世界范围的增长也把大大小小的城镇纳入基于全球价值链的城市体系之... 详细信息

在城市发展史中,城市参与了现代国家的建构,现代城市从单一的国家权力表征逐步嬗变为资本与社会的空间结果。基于工商业的快速推动,国家对于城市的控制开始松动,城市在世界范围的增长也把大大小小的城镇纳入基于全球价值链的城市体系之中。但是不受控制的、基于资本的权力同样支配了城乡之间和城市内部的空间分布,进而损害了城市的核心价值。人民国家意味着人民主权,国家的城市与人民的城市拥有一致的政治目标;城市增长到城市高质量发展的转变,高水平的城市治理和高标准的公共生活,正是这一目标的体现。而实现这一目标仍然需要国家以妥善的形式重新进入城市,在权力自我约束的前提下,以人民性统领城市性,以人民性规范城市发展路径。

关键词：国家城市城市政治国家仪轨人民至上高质量发展

维普期刊数据库博看期刊

在线全文

学校读者我要写书评

暂无评论

风洞尺寸对高速列车气动性能的影响

中南大学学报（自然科学版） 2024年第5期55卷 1880-1888页

作者：张业杜健尚克明中车青岛四方机车车辆股份有限公司山东青岛266111

采用单因素变量法则,研究风洞尺寸对高速列车气动性能的影响。基于DDES湍流模拟方法采用不可压缩Navier−Stokes方程求解三维非定常流场,得到不同风洞尺寸下1꞉8缩比的高速列车气动性能,并通过与风洞试验结果的对比验证仿真结果的可靠性... 详细信息

采用单因素变量法则,研究风洞尺寸对高速列车气动性能的影响。基于DDES湍流模拟方法采用不可压缩Navier−Stokes方程求解三维非定常流场,得到不同风洞尺寸下1꞉8缩比的高速列车气动性能,并通过与风洞试验结果的对比验证仿真结果的可靠性。研究结果表明:随着风洞尺寸的减小,风洞的阻塞比增大,列车周围气流加速效应更加明显,导致列车表面正负压强均增大,涡强度增加,所受气动阻力、升力增大,当风洞阻塞比从0.61%增加到4.17%时,列车气动阻力增加15%。为获得更好的试验结果,应尽量在大尺寸风洞中进行风洞试验,以减小风洞阻塞效应对实验结果的干扰。

关键词：高速列车气动特性风洞尺寸分离涡方法(DES)