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Science China Chemistry 2024年第10期67卷 3432-3437页

作者： Xianzhe Wei Jincheng Liu Yan Su weitao wang Guixiang wang Gen Zhang Ping wang Cheng Gu State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of TechnologyGuangzhou 510640China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China

Designing efficient proton-conductive materials is crucial in fuel ***,it remains a substantial challenge because of the issues in proton mobility,proton-carrier amount,and orientation of proton host ***,we report an in-situ protonation strategy to produce a locally flexible porous coordination polymer(PCP)to enhance the proton-carrier loading and proton *** local dipole flipping of the ligand allows effective proton exchange with low activation energy,promoting interpore proton transport through the pore apertures and pore *** protonation induces substantial charges to the frameworks and enhances the interaction with proton carriers,thereby increasing the loading of the proton *** this design strategy,the resulting PCP exhibits enhanced phosphoric acid loading and extraordinary proton conductivities under both aqueous and anhydrous conditions compared to its isoreticular analog that features rigidity without proton-exchange *** work provides a new avenue for designing proton-conductive materials that combine structural dynamics with performance merits.

关键词： porous coordination polymers in-situ protonation local flexibility proton-exchange mechanism proton conduction

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CREDIT-X1local:A reference dataset for machine learning seismology from ChinArray in Southwest China

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Earthquake Science 2024年第2期37卷 139-157页

作者： Lu Li weitao wang Ziye Yu Yini Chen Institute of Geophysics China Earthquake AdministrationBeijing 100081China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China Zhejiang Earthquake Agency HangzhouZhejiang 310013China

High-quality datasets are critical for the development of advanced machine-learning algorithms in ***,we present an earthquake dataset based on the ChinArray Phase I records(X1).ChinArray Phase I was deployed in the southern north-south seismic zone(20°N-32°N,95°E-110°E)in 2011-2013 using 355 portable broadband seismic ***-X1local,the first release of the ChinArray Reference Earthquake Dataset for Innovative Techniques(CREDIT),includes comprehensive information for the 105,455 local events that occurred in the southern north-south seismic zone during array observation,incorporating them into a single HDF5 *** 100-Hz sampled three-component waveforms are organized by event for stations within epicenter distances of 1,000 km,and records of≥200 s are included for each *** types of phase labels are *** first includes manually picked labels for 5,999 events with magnitudes≥2.0,providing 66,507 Pg,42,310 Sg,12,823 Pn,and 546 Sn *** second contains automatically labeled phases for 105,442 events with magnitudes of−1.6 to *** phases were picked using a recurrent neural network phase picker and screened using the corresponding travel time curves,resulting in 1,179,808 Pg,884,281 Sg,176,089 Pn,and 22,986 Sn ***,first-motion polarities are included for 31,273 Pg *** event and station locations are provided,so that deep learning networks for both conventional phase picking and phase association can be trained and *** CREDIT-X1local dataset is the first million-scale dataset constructed from a dense seismic array,which is designed to support various multi-station deep-learning methods,high-precision focal mechanism inversion,and seismic tomography ***,owing to the high seismicity in the southern north-south seismic zone in China,this dataset has great potential for future scientific discoveries.

关键词： earthquake dataset machine learning Pg/Sg/Pn/Sn phase picking P-wave first-motion polarity

Accurate crop row recognition of maize at the seedling stage using lightweight network

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 189-198,I0001页

作者： Jian Wei Mengfan Zhang Caicong Wu Qin Ma weitao wang Chuanfeng Wan College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Agricultural Machinery Monitoring and Big Data Applications Ministry of Agriculture and Rural AffairsBeijing 100083China

Accurate extraction of crop row is very important for automation of agricultural *** rows are required for accurate machine guidance in agricultural production such as fertilization,plant protection,weeding and *** this study,an efficient crop row detection algorithm called Crop-BiSeNet V2 was proposed,which combined BiSeNet V2 with a spatial convolutional neural *** proposed Crop-BiSeNet V2 detected crop rows in color images without the use of threshold and other pre-information such as number of rows.A data set had 2697 maize crop images was constructed in challenging field trial conditions such as variable light,shadows,presence of weeds,and irregular crop *** proposed system was experimentally determined to overcome the interference of different complex *** it can be applied to crop rows of different numbers,straight lines and *** analyses were performed to check the robustness of the *** this algorithm with the Fully Convolutional Networks(FCN)algorithm,it exhibited superior performance and saved 84.85 *** accuracy rate reached 0.9811,and the detection speed reached 65.54 ms/*** Crop-BiSeNet V2 algorithm proposed in this study show strong generalization performance for seedling crop row *** provides high-reliability technical support for crop row detection research and assists in the study of intelligent field operation machinery navigation.

关键词： computer vision crop row detection precision agriculture semantic segmentation

A phylogenetic approach identifies patterns of beta diversity and floristic subregions of the Qinghai-Tibet Plateau

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Plant Diversity 2024年第1期46卷 59-69页

作者： Haibin Yu Man Yang Zixin Lu weitao wang Fangyuan Yu Yonghua Zhang Xue Yin Hongjun Yu Junjie Hu David C.Deane Key Laboratory of Conservation and Application in Biodiversity of South China School of Life SciencesGuangzhou UniversityGuangzhou 510006China School of Ecology Sun Yat-Sen UniversityShenzhen 510275China School of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006China College of Life and Environmental Science Wenzhou UniversityWenzhou 325035China Centre for Future Landscapes and Department of Environment and Genetics La Trobe UniversityBundooraVIC 3083Australia

Patterns of taxonomic and phylogenetic beta diversity and their relationships with environmental correlates can help reveal the origin and evolutionary history of regional *** Qinghai-Tibet Plateau(QTP)harbors an exceptionally diverse flora,however,a phylogenetic perspective has rarely been used to investigate its beta diversity and floristic *** this study,we used a phylogenetic approach to identify patterns of beta diversity and quantitatively delimit floristic regions on the Qinghai-Tibet *** also examined the relationships between multifaceted beta diversity,geographical distance,and climatic difference,and evaluated the relative importance of various factors(i.e.,climate,topography and history)in shaping patterns of beta diversity.Sørensen dissimilarity indices indicated that patterns of species turnover among sites dominated the *** also found that patterns of both taxonomic and phylogenetic beta diversity were significantly related to geographical distance and climatic *** environmental factors that contributed most to these patterns of beta diversity include annual precipitation,mean annual temperature,climatic gradients and climatic *** dendrograms of dissimilarity and non-metric multidimensional scaling ordination based on phylogenetic beta diversity data identified ten floristic subregions in the *** results suggest that the contemporary environment and historical climate changes have filtered species composition among sites and eventually determined beta diversity patterns of plants in the QTP.

关键词： Biogeographical regionalization Phylogenetic beta diversity Seed plants Sørensen dissimilarity Qinghai-Tibet Plateau

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论云冈第13窟窟顶图像的来源与传播

艺术探索 2024年第4期38卷 78-85页

作者：王韦韬南京艺术学院美术与书法学院江苏南京210013

云冈第13窟窟顶图像由依附于主尊身光上方的弧状纹样带与两条交缠的龙组成。窟顶依附于主尊身光上缘的弧状纹样带,最早可追溯至犍陀罗、秣菟罗地区佛教造像中尊像身后的树木,被称为“华盖式圣树”。此窟窟顶纹样带内部忍冬枝藤所结果实... 详细信息

云冈第13窟窟顶图像由依附于主尊身光上方的弧状纹样带与两条交缠的龙组成。窟顶依附于主尊身光上缘的弧状纹样带,最早可追溯至犍陀罗、秣菟罗地区佛教造像中尊像身后的树木,被称为“华盖式圣树”。此窟窟顶纹样带内部忍冬枝藤所结果实或代表了兜率天中“果如颇黎色”的七宝行树,与同样位于窟顶的交龙(或为护树、为树布雨的龙王)共同构成了兜率天胜景。豫北北魏背屏式造像侧面纹饰及龙门石窟北魏晚期圆楣龛圆楣、部分造像龛主尊内层身光顶部的忍冬纹都与云冈第13窟窟顶图像存在不同程度的亲缘关系。

关键词：圣树弧状纹样带忍冬纹龙

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西秦岭造山带晚中生代-新生代陆内构造演化

科学通报 2024年第18期69卷 2568-2586页

作者：张逸鹏张培震王岳军许斌斌王伟涛中山大学地球科学与工程学院广东省地球动力作用与地质灾害重点实验室珠海519080 南方海洋科学与工程广东省实验室(珠海) 珠海519080 广东省地震局广州510070

晚中生代以来,东亚大陆处于太平洋和特提斯构造域多向汇聚的叠加区域,其陆内变形过程与陆缘板块的俯冲和碰撞作用紧密相连.西秦岭造山带位于中国大陆中部,是理解东亚大陆内部构造演化与动力学过程的关键区域.在对西秦岭造山带晚中生代-... 详细信息

晚中生代以来,东亚大陆处于太平洋和特提斯构造域多向汇聚的叠加区域,其陆内变形过程与陆缘板块的俯冲和碰撞作用紧密相连.西秦岭造山带位于中国大陆中部,是理解东亚大陆内部构造演化与动力学过程的关键区域.在对西秦岭造山带晚中生代-新生代陆内构造格架划分和主要构造形迹及其运动学特征观测的基础上,本文基于断层滑动矢量应力反演理论和方法,在露头尺度获取了1215组断层滑动矢量数据,共划分出四期古构造应力场序列,整体表现为最大主应力方向顺时针旋转的过程,表明西秦岭陆内变形受太平洋构造域的影响逐渐减弱,而相应受特提斯构造域的作用逐渐增强.西秦岭早白垩世以NW-SE向伸展应力场为主(D1,约145~105 Ma),造山带内部发育一系列断陷盆地,这与东亚同汇聚背景下的造山带伸展构造作用息息相关.之后,西秦岭以N-S向伸展与EW向弱挤压共存的应力场为主(D2,约105~65 Ma),造山带内部的构造变形幅度较弱,西秦岭向着稳定的克拉通方向逐渐发展,同时广泛的剥蚀作用使得区域开始形成准平原化的地貌.继而,西秦岭逐渐受NW-SE向和N-S向叠加的挤压应力场所影响(D3,约50~30 Ma),导致全区以广泛的收缩构造变形为主,揭示出区域受到太平洋和特提斯构造域多向汇聚作用的共同影响.最后,西秦岭以NE-SW向挤压应力为主(D4,约22~5 Ma),区域新生代盆地整体抬升,缺乏显著的收缩构造变形,这是由于青藏高原侧向生长导致高原中部至西秦岭的中-下地壳和岩石圈地幔挤出的构造作用所致.这种“伸展垮塌-剥蚀夷平-活化隆升”是陆内造山带受多个构造域控制和发展的一般规律,并且陆内变形总是受控于最为活动的构造域,其转变过程是渐变的.

关键词：中央造山带西秦岭造山带陆内变形应力反演古构造应力场

全球近期“非典型”海啸源事件机制分析及其对南海海啸研究的启示

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科学通报 2024年第18期69卷 2480-2497页

作者：李琳琳胡桂王伟涛张坎杜朋李志刚王培涛王大伟邱强张培震中山大学地球科学与工程学院南方海洋科学与工程广东省实验室(珠海)广东省地球动力作用与地质灾害重点实验室珠海519080 国家海洋环境预报中心北京100081 中国科学院深海科学与工程研究所三亚572000 中国科学院边缘海与大洋地质重点实验室中国科学院南海海洋研究所广州510301

2018年以来,全球发生了多起“非典型”海啸源事件,其中包括2018年9月印度尼西亚Sulawesi岛Mw 7.5走滑地震在Palu湾引发的灾害链事件、2018年12月印度尼西亚巽他海峡Anak Krakatau海啸事件、2020年10月欧洲东爱琴海Samos岛北部海域Mw 6.... 详细信息

2018年以来,全球发生了多起“非典型”海啸源事件,其中包括2018年9月印度尼西亚Sulawesi岛Mw 7.5走滑地震在Palu湾引发的灾害链事件、2018年12月印度尼西亚巽他海峡Anak Krakatau海啸事件、2020年10月欧洲东爱琴海Samos岛北部海域Mw 6.9正断层地震海啸事件和2022年1月15日南太平洋汤加火山海啸事件等.目前科学家对这些“非典型”海啸源触发海啸机制与过程的认知非常有限,现有灾害防御系统也很难对这些“出人意料”的极端灾害事件作出及时响应,从而造成重大人员伤亡和经济损失.本文针对“非典型”海啸事件的触发机制深入剖析,揭示地震导致沿岸/海底砂土液化,继而触发滑坡并产生海啸的链生效应;沿海特殊岸线形态;火山剧烈活动引起的大气-海洋-火山固体物质多相耦合作用等是“非典型”海啸源触发机制复杂化的主要原因.这些机制挑战了海啸形成需伴随海域地震造成的大规模垂向形变这一传统认识,发现海域的正断型和走滑型地震、陆地近岸地震、剧烈火山喷发均可触发链生海啸灾害.结合我国南海及其周边海域的构造特征与历史“非典型”海啸源事件分析,文章指出了南海“非典型”海啸源(南海北部板内地震、周缘火山等)分布特点和致灾机制,提出未来南海“非典型”海啸源灾害的重点研究方向.

关键词：海啸灾害致灾机制板内地震火山活动链生效应

前庭性偏头痛的自然-人文-环境胁迫因素研究进展

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中华耳科学杂志 2024年第2期22卷 267-270页

作者：王理想王伟涛张道培张怀亮河南中医药大学第一附属医院脑病科河南中医药大学第一临床医学院郑州450000 北京中医药大学河南省眩晕病诊疗中心河南中医药大学眩晕病研究所

前庭性偏头痛(vestibular migraine,VM)是一种以前庭症状为主,临床常见的反复发作性眩晕类疾病。自然环境和社会人文环境的变化常能胁迫VM的发作。环境胁迫诱发VM的机制可能与脑肠轴、神经环路、神经解剖以及感觉整合异常等多方面有关... 详细信息

前庭性偏头痛(vestibular migraine,VM)是一种以前庭症状为主,临床常见的反复发作性眩晕类疾病。自然环境和社会人文环境的变化常能胁迫VM的发作。环境胁迫诱发VM的机制可能与脑肠轴、神经环路、神经解剖以及感觉整合异常等多方面有关。环境胁迫因素诱发VM发病机制的揭示,对VM的防治具有重要的临床意义。

关键词：前庭性偏头痛偏头痛环境胁迫环境因素诱发疾病脑肠轴

微波照射下附着砂浆对再生混凝土粗骨料强度的影响

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材料科学与工程学报 2024年第1期42卷 27-34页

作者：邵珠山王维涛赵冬袁媛郭轩西安建筑科技大学理学院陕西西安710055 陕西省岩土与地下空间工程重点实验室陕西西安710055

微波照射回收废弃混凝土中的粗骨料是一种高效、节能、环保的混凝土再资源化技术。粗骨料表面附着砂浆耗散的微波能量对于回收粗骨料的质量有显著影响。本实验选取了两种常见的粗骨料,花岗岩和玄武岩,制成表面包裹均匀厚度砂浆的试样进... 详细信息

微波照射回收废弃混凝土中的粗骨料是一种高效、节能、环保的混凝土再资源化技术。粗骨料表面附着砂浆耗散的微波能量对于回收粗骨料的质量有显著影响。本实验选取了两种常见的粗骨料,花岗岩和玄武岩,制成表面包裹均匀厚度砂浆的试样进行微波加热试验,研究了不同的砂浆厚度和含水率下试样表面的温度变化,并对微波照射后砂浆失水特性、裂纹扩展及破坏特征进行了分析。微波加热结束后剔除粗骨料表面剩余的附着砂浆,选取形状完整未发生熔融的粗骨料进行单轴抗压强度测试,研究包裹砂浆对微波照射粗骨料强度折减的影响。结果表明:微波照射后花岗岩和玄武岩骨料的强度随粘结砂浆含水量的增加而增加;微波照射后花岗岩骨料强度随黏附砂浆厚度增加而增加,玄武岩骨料强度随黏附砂浆厚度增加呈下降趋势。与厚度相比,砂浆的含水率对微波加热后粗骨料的强度影响更大。

关键词：混凝土微波加热砂浆厚度含水率强度弱化

基于分离源矩阵变换器的PMSM无源动态演化控制策略

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高电压技术 2024年第5期50卷 2030-2041页

作者：程启明罗力珲沈治超王为涛张梁王海伦上海市电站自动化技术重点实验室(上海电力大学自动化工程学院) 上海200090

为了改进传统的永磁同步电机驱动器系统及其PID控制的不足,提出了一种无源动态演化控制策略,并应用于永磁同步电机(permanent magnet synchronous motor,PMSM)和分离源矩阵变换器(split source matrix con-verter,SSMC)中。为打破传统... 详细信息

为了改进传统的永磁同步电机驱动器系统及其PID控制的不足,提出了一种无源动态演化控制策略,并应用于永磁同步电机(permanent magnet synchronous motor,PMSM)和分离源矩阵变换器(split source matrix con-verter,SSMC)中。为打破传统矩阵变换器电压传输比0.866的限制,采用电感、电容和3个二极管代替了双级矩阵变换器中间的支流链路部件,并且证明了分离源网络的升压能力。另外,在矢量控制中,永磁同步电机的转速外环和电流内环都使用了传统PID控制器,但由于PID控制器的参数调节比较困难、控制精度不高、超调量较大和抗干扰能力不强等问题,为此提出了基于动态演化理论和无源理论的控制策略,设计了分离源矩阵变换器和永磁同步电机系统基于互联和阻尼分配(the interconnection and damping assignment,IDA)的无源控制器(passivity-based control,PBC)和动态演化控制器(dynamic evolution controller,DEC)。仿真与实验的结果表明,基于该控制策略的SSMC-PMSM驱动系统能够使永磁同步电机稳定运行在额定转速,并且具有稳定性强、抗干扰能力强和动态响应好等特点。

关键词：分离源矩阵变换器电压传输比永磁同步电机无源理论动态演化理论 PID控制