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分级车辆火灾下吊索系统的抗火性能计算方法

中国公路学报 2024年第9期37卷 1-16页

作者：刘志李国强同济大学土木工程学院上海200092 同济大学土木工程防灾减灾全国重点实验室上海200092

为计算车辆火灾下悬索桥吊索系统的抗火性能,将桥梁车辆火灾分为五级:第一、二级为乘用车火灾,第三、四级为货车火灾,第五级为油罐车火灾,采用不同的最大热释放速率和最大燃烧时长对其进行表征。根据已有的车辆火灾试验,验证该分级方法... 详细信息

为计算车辆火灾下悬索桥吊索系统的抗火性能,将桥梁车辆火灾分为五级:第一、二级为乘用车火灾,第三、四级为货车火灾,第五级为油罐车火灾,采用不同的最大热释放速率和最大燃烧时长对其进行表征。根据已有的车辆火灾试验,验证该分级方法的合理性,并结合车辆火灾事故,建立第三、四、五级车辆火灾火源的几何特征。采用圆柱火焰辐射体模型,计算乘用车火灾的空间辐射热流密度,并得到3例足尺汽车火灾试验的验证;采用棱柱火焰辐射体模型,计算货车火灾的空间辐射热流密度;采用经液化天然气池火试验验证的计算流体动力学方法,计算有横风时油罐车火灾下吊索表面的空间热流密度包络;推导了吊索截面在辐射热流密度边界条件下的增量法升温计算公式,并得到了有限元模型的验证。根据已有的高强钢丝高温力学性能试验,基于吊索在火灾下的承载能力极限状态,提出了吊索临界温度与吊索设计安全系数的函数关系。最后,整合上述研究结果,提出了分级车辆火灾下吊索系统抗火性能的五步计算方法,可为悬索桥吊索系统的抗火安全评定与设计提供参考。

关键词：桥梁工程车辆火灾理论分析吊索系统抗火性能悬索桥

基于车轮-桥面相干激励的大跨连续梁桥振动响应

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吉林大学学报（工学版） 2024年第2期54卷 436-444页

作者：韩智强谢刚卓亚娟骆佐龙李华腾太原科技大学车辆与交通工程学院太原030024 太原科技大学先进控制与装备智能化山西省重点实验室太原030024 山西大学电力与建筑学院太原030024

为获取桥面相干激励下大跨连续梁桥动力响应规律,基于虚功原理,建立五轴重载车辆动力学模型,采用模态叠加法建立桥梁动力方程,通过谐波叠加法建立桥面相干激励模型,根据轮-桥间几何和力学耦合关系,组建车轮-桥面相干激励模型,采用Matla... 详细信息

为获取桥面相干激励下大跨连续梁桥动力响应规律,基于虚功原理,建立五轴重载车辆动力学模型,采用模态叠加法建立桥梁动力方程,通过谐波叠加法建立桥面相干激励模型,根据轮-桥间几何和力学耦合关系,组建车轮-桥面相干激励模型,采用Matlab软件编译大跨连续梁桥车桥耦合振动分析系统,并开展不同等级的相干桥面激励模型对大跨连续梁桥动力响应影响研究。结果表明:当未考虑桥面不平顺影响时,桥梁冲击系数均小于规范取值,但随着桥面状况的恶化,结构典型截面的动力响应增长较快,且完全相干模型对桥梁动力响应的影响均大于部分相干激励模型,均超过规范值,其中挠度幅值最大偏差约为7.7%,弯矩幅值最大偏差约为20%,挠度冲击系数相对误差为4%~34%,弯矩冲击系数相对误差为2%~43%;随着车速的增大,桥梁冲击系数呈先增大后减小变化。最后,给出了大跨连续梁桥挠度和弯矩冲击系数包络图。相关研究成果可为连续梁桥的结构动力响应的分析与研究提供参考。

关键词：桥梁工程桥面相干激励模型车桥耦合动力响应冲击系数

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What Controls the Distribution of Ore Veins in Quartz Vein-type Tungsten Deposits: Constrains from Fan-shaped Mineralization in SE China

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Journal of Earth Science 2024年

作者： Gui-Cong Fang Deng-Hong Wang Fu-qiang Yang Zhan-Xu Ni Chang-Shuai Huang Ping Wang Meng Feng zuo-Hai Feng Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration， College of Earth Science， Guilin University of Technology Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources By the Province and Ministry，Guilin University of Technology Institute of Mineral Resources， Chinese Academy of Geological Sciences Guangxi Zhuang Autonomous Region Institute of Geophysical Exploration Geological Team No.271 of Guangxi Zhuang Autonomous Region China Nonferrous Metal Guilin Research Institute of Geology for Mineral Resources Co.， Ltd Guangdong Geologic Survey Institute

Quartz vein-type tungsten deposits are a common W deposit type. Their ore vein distribution was previously considered to be controlled by regional horizontal tectonic stress. In this paper， 14 tungsten deposits with fan-shaped mineralization in SE China are summarized， and the relations between their ore veins and granite and the ore-forming structural stress field are analyzed. These deposits have a post-magmatic hydrothermal genesis and involve the formation of two sets of veins with similar strike and opposite dips at the top of the ore-causative granite bodies， forming a vertical fan-shaped profile. Their ore veins were coeval with the underlying granite bodies， and generally extend along the long axis of the granite. In such fan-shaped ore formation， the stress is highly focused at the top of the granite and gradually weakens outward. The maximum principal stress (σ1) is perpendicular to the granite contact surface， and radiates outward from the pluton. Meanwhile， the minimum principal stress (σ3) forms an arc-shaped band parallel to the contact surface. Our findings， together with published numerical modeling indicate that the emplacement dynamics of granitic magma (rather than regional horizontal tectonic stress) are essential controls on the distribution of ore veins in quartz vein-type tungsten deposits.

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Chromosome-level genome assembly of the glass catfish(Kryptopterus vitreolus)reveals molecular clues to its transparent phenotype

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Zoological Research 2024年第5期45卷 1027-1036页

作者： Chao Bian Rui-Han Li zhi-qiang Ruan Wei-Ting Chen Yu Huang Li-Yue Liu Hong-Ling Zhou Cheong-Meng Chong Xi-Dong Mu Qiong Shi Laboratory of Aquatic Genomics College of Life Sciences and OceanographyShenzhen UniversityShenzhenGuangdong 518057China Key Laboratory of Prevention and Control for Aquatic Invasive Alien Species Ministry of Agriculture and Rural AffairsGuangdong Modern.Recreational Fisheries Engineering Technology CenterPearl River Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhouGuangdong 510380China Shenzhen Key Lab of Marine Genomics Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic AnimalsBGI Academy of Marine SciencesBGI MarineShenzhenGuangdong 518081China CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengduSichuan 610041China School of Life Sciences Jiaying UniversityMeizhouGuangdong 514015China China Zebrafish Resource Center National Aquatic Biological Resource CenterState Key Laboratory of Freshwater Ecology and BiotechnologyInstitute of HydrobiologyChinese Academy of ScienceWuhanHubei 430072China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong 518116China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacaoMacao 999078China Center for Aquatic Genomics College of Life SciencesNeijiang Normal UniversityNeijiangSichuan 641100China

Glass catfish(Kryptopterus vitreolus)are notable in the aquarium trade for their highly transparent body *** transparency is due to the loss of most reflective iridophores and light-absorbing melanophores in the main body,although certain black and silver pigments remain in the face and *** date,however,the molecular mechanisms underlying this transparent phenotype remain largely *** explore the genetic basis of this transparency,we constructed a chromosome-level haplotypic genome assembly for the glass catfish,encompassing 32 chromosomes and 23344 protein-coding genes,using PacBio and Hi-C sequencing technologies and standard assembly and annotation *** revealed a premature stop codon in the putative albinism-related tyrp1b gene,encoding tyrosinase-related protein 1,rendering it a nonfunctional ***,a synteny comparison with over 30 other fish species identified the loss of the endothelin-3(edn3b)gene in the glass catfish *** investigate the role of edn3b,we generated edn3b^(−/−)mutant zebrafish,which exhibited a remarkable reduction in black pigments in body surface stripes compared to wild-type *** findings indicate that edn3b loss contributes to the transparent phenotype of the glass *** high-quality chromosome-scale genome assembly and identification of key genes provide important molecular insights into the transparent phenotype of glass *** findings not only enhance our understanding of the molecular mechanisms underlying transparency in glass catfish,but also offer a valuable genetic resource for further research on pigmentation in various animal species.

关键词： Glass catfish Whole-genome sequencing edn3b−/−mutant Transparent phenotype

Magnetostratigraphy and paleoenvironmental record of late Cenozoic sediments in the Taiyuan Basin,North China

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Journal of Palaeogeography 2024年第4期13卷 971-992页

作者： zhi-qiang Feng Qian LI Wei Han Kun-Yuan Ma Yong-Jiang Liu Rong-Zhu Wei Yan-Wei Du Yong Lei Guang-Hui Li College of Geoscience and Geomatics Engineering Taiyuan University of Technology Shanxi Institute of Geological Survey Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Lab of Submarine Geoscience and Prospecting TechniquesCollege of Manine GeosciencesOcean University of China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology College of Resources and Environment Shanxi Agricultural University Department of Information Engineering Shanxi University

The Taiyuan Basin is of importance for intraplate tectonic deformation in North China and contains Cenozoic strata with a maximum thickness of 3800 m.A～853.5-m-deep borehole (ZK01) with an overall core recovery rate of 85.09%was drilled at Yuci (37°35'37?N,112°39'47?E) in the central Taiyuan Basin,to obtain high-resolution records of paleomagnetism,paleoclimatic and paleoenvironmental conditions,and depositional environment of the *** obtained magnetic polarity sequence consists of 13 normal and 12 reverse zones,which correspond to C1n-C4An.2n of the geomagnetic polarity time *** data show that the evolution of ZK01 core covers the interval from 8.1 Ma to the present,and the bottoms of Pliocene,Quaternary,and Middle Pleistocene were identified in Taiyuan Basin,with a sedimentary accumulation rate ranging from 62.5 m/Ma to 175.9 m/*** data reveal that the source rocks in the study area underwent intense weathering and the sediments mainly formed in a semi-arid and oxygen-rich *** addition,paleoclimatic changes occurred at～7 Ma,3.8 Ma,and 1.7 Ma,which can be closely related to the tectonic uplift of the Loess Plateau and Tibetan Plateau,as well as the variations in the Asian monsoon and associated regional and global climatic change.

关键词： Taiyuan Basin Core sediment Magnetostratigraphy Climate change Paleoenvironment Quaternary

High-speed GeSn resonance cavity enhanced photodetectors for a 50 Gbps Si-based 2 μm band communication system

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Photonics Research 2024年第4期12卷 767-773页

作者： JINLAI CUI JUN ZHENG YUPENG ZHU XIANGQUAN LIU YIYANG WU QINXING HUANG YAZHOU YANG zhiPENG LIU zhi LIU YUHUA zuo BUWEN CHENG Key Laboratory of Optoelectronic Materials and Devices Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Expanding the optical communication band is one of the most effective methods of overcoming the nonlinear Shannon capacity limit of single *** this study,GeSn resonance cavity enhanced(RCE)photodetectors(PDs)with an active layer Sn component of 9%–10.8%were designed and fabricated on an SOI *** GeSn RCE PDs present a responsivity of 0.49 A/W at 2μm and a 3-dB bandwidth of approximately 40 GHz at 2μ***,Si-based 2μm band optical communication with a transmission rate of 50 Gbps was demonstrated by using a GeSn RCE *** work demonstrates the considerable potential of the Si-based 2μm band photonics in future high-speed and high-capacity optical communication.

关键词： resonance system approximate

Broadband third-order optical nonlinearities of layered franckeite towards mid-infrared regime

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Chinese Physics B 2024年第10期33卷 275-281页

作者： zhi-qiang Xu Tian-Tian Zhou Jie Li Dong-Yang Liu Yuan He Ning Li Xiao Liu Li-Li Miao Chu-Jun Zhao Shuang-Chun Wen Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China School of Mechanical and Electrical Engineering Heze UniversityHeze 274015China

The study of nonlinear optical responses in the mid-infrared(mid-IR)regime is essential for advancing ultrafast mid-IR laser ***,nonlinear optical effects under mid-IR excitation are rarely reported due to the lack of suitable nonlinear optical *** natural van derWaals heterostructure franckeite,known for its narrow bandgap and stability in air,shows great potential for developing mid-IR nonlinear optical *** have experimentally demonstrated that layered franckeite exhibits a broadband wavelength-dependent nonlinear optical response in the mid-IR spectral *** nanosheets were prepared using a liquid-phase exfoliation method,and their nonlinear optical response was characterized in the spectral range of 3000 nm to 5000 *** franckeite nanosheets exhibit broadband wavelengthdependent third-order nonlinearities,with nonlinear absorption and refraction coefficients estimated to be about 10^(-7)cm/W and 10^(-11)cm^(2)/W,***,a passively Q-switched fluoride fiber laser operating around a wavelength of 2800 nm was achieved,delivering nanosecond pulses with a signal-to-noise ratio of 43.6 dB,based on the nonlinear response of *** findings indicate that layered franckeite possesses broadband nonlinear optical characteristics in the mid-IR region,potentially enabling new possibilities for mid-IR photonic devices.

关键词： third-order optical nonlinearities franckeite mid-infrared Q-switching

Irreducible anteromedial radial head dislocation without fracture caused by transposed biceps tendon in an adult:A case report and literature review

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Chinese Journal of Traumatology 2024年第3期27卷 180-186页

作者： Ming-Fu Fu Hai-Ning zuo Tao Sun Ming-Zhang Mu zhi-Yong Zhou Department of Orthopedic Surgery Yantaishan HospitalYantaiShandong Province264003China

Irreducible anteromedial radial head dislocation(IARHD)caused by transposed biceps tendon is *** diagnosis and surgical failure often occur.A 46-year-old fisherman presented with 10 days history of painful swelling and restricted movement of his right elbow due to strangulation injury by a fishing boat *** examination,the images of the right elbow reveals in a"semi-extended and pronated"elastic fixation *** and 3-dimensional reconstruction CT reveals an isolated anteromedial radial head dislocation with extreme protonation of the radius and the bicipital tuberosity towards the posterior aspect of the elbow joint,and MRI shows biceps tendon wrapping around the radial neck,similar to umbilical cord wrapping seen in *** Henry approach was applied for the first time to reduce the biceps *** patient achieved a good functional recovery at 26 months,which represents the first reported case of IARHD without fracture caused by biceps tendon in an *** treatment of IARHD,attention should be paid to the phenomenon of biceps tendon *** clinical examination,comprehensive imaging modalities,and appropriate surgical approach are the keys to successful management.

关键词： Biceps tendon Henry approach Irreducible Anteromedial dislocation Radial head Elbow Adult

Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

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Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang Yong-Qing Liu qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang Da-Wei Qiao Xiao-Shuai Chen Li-zhi Wu Meng Tian Long Chen Yi Wei Liao-Yuan Song Jian Li Zi-Gang Wu Yun-Qian Liu Xuan-Chun Liu An-Qing Chen zhi-Wei Liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original Chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating