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Optoelectronics Letters 2024年第3期20卷 135-141页

作者： PAN Honggang ZHANG Bo SONG Dianyou CHEN Zhipan CHEN Chunqi li Rupeng School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin 300384China

In this paper, an actively Q-switched wavelength injection locking random fiber laser(RFL) based on random phase-shifted fiber Bragg grating(RPS-FBG) is proposed, and the performance of the laser is verified by experiments. Within the reflection bandwidth range of RPS-FBG, spanning from 1 549.2 nm to 1 549.9 nm, different laser modes with stable central wavelength and peak power can be selectively chosen by varying the injected light wavelength. The power fluctuation within 1 h is less than 0.1 d Bm, and the central wavelength drift is less than 0.02 nm. When the pump power increases from 90 mW to 300 mW, the pulse width decreases from 3.2 μs to 1.5 μs, and the pulse repetition frequency is 20 kHz. The RFL can reach a stable locking state at the lowest pump power of 100 mW and the lowest injection power of 3 d Bm. When the wavelength is locked, the output pulse is a single pulse. On the contrary, the unlocked output pulse is multi-pulse. The laser has the characteristics of high wavelength tunability in the reflection range of RPS-FBG and it can be an ideal light source in the fields of laser imaging and pulse coding.

关键词： fiber switched modulator

Natural Disaster Risk Monitoring for Immovable Cultural Relics Based on Digital Twin

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Journal of Geodesy and Geoinformation Science 2024年第1期7卷 90-104页

作者： li Bolun DONG Youqiang QIAO Yunfei HOU Miaole WEN Caihuan The International Joint Laboratory of Safety and Energy Conservation for Ancient Buildings Beijing University of Civil Engineering and ArchitectureBeijing 102616China China Cultural Heritage Information and Consulting Center Beijing 100029China Hebei Institute of Geological Surveying and Mapping Langfang 065000China

Natural disaster risk monitoring is an important task for disaster prevention and *** the case of immovable cultural relics,however,the feedback mechanism,risk factors,monitoring logic,and monitoring indicators of natural disaster risk monitoring are *** to achieve intelligent perception and monitoring of natural disaster risk for immovable cultural relics has always been a focus and a challenge for *** on the analysis of the concepts and issues related to the natural disaster risk of immovable cultural relics,this paper proposes a framework for natural disaster risk monitoring for immovable cultural relics based on the digital *** framework focuses on risk monitoring,including the physical entities of natural disaster risk for immovable cultural relics,monitoring indicators,and virtual entity construction.A platform for monitoring the natural disaster risk of immovable cultural relics is *** the Puzhou Ancient City Site as a test bed,the proposed concept can be used for monitoring the natural disaster risk of immovable cultural relics at different scales.

关键词： immovable cultural relics natural disaster risk digital twin risk monitoring

Thermal decomposition mechanism and kinetics of bastnaesite in suspension roasting process:A comparative study in N2 and air atmospheres

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Journal of Rare Earths 2024年第9期42卷 1809-1816页

作者： Wenbo li Jijia Chen Shaokai Cheng Junyan Sun Xiaolong Zhang School of Resources and Civil Engineering Northeastern University National-Local Joint Engineering Research Center of High-Efficient Exploitation Technology for Refractory Iron Ore Resources

To investigate the thermal decomposition behavior and reaction kinetics of bastnaesite in suspension roasting,the gas and solid products of bastnaesite roasted in N2 and air atmospheres were examined using a gas analyzer,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,and energy dispersive spectrometry（EDS）.Subsequently,the kinetic parameters of bastnaesite in the suspension roasting process were derived and calculated using the isothermal *** results show that the decomposition product of bastnaesite in N2is ***,once the roasting temperature exceeds 600℃,CO is generated in addition to CO2,and all the XRD diffraction peaks of CeOF are shifted to the right,indicating that CO2can oxidize CeOF and lead to the transformation of Ce（Ⅲ） into Ce（Ⅳ）.When roasted in air,the decomposition product CeOF can be completely converted to CeF3 and Ce7O12as it easily ***,the reaction rate of bastnaesite in air is higher than that of N2,and the starting reaction temperature is lower than that of N2.A large number of irregular cracks and holes appear on the surface of solid-phase products following suspension roasting,which are due to the thermal decomposition of bastnaesite that produces CO2as well as the reconstruction of the lattice of the solid-phase *** reaction kinetic model of bastnaesite roasted in N2（temperature range 600-750℃） and air（temperatu re range 500-575℃） confo rms to the A3/2model with the mechanism function G（α）=-ln（1-α）2/3,and the reaction activation energy is 59.78 kj/mol and lnA is 1.65 s-1in *** air,the reaction activation energy is 100.30 kj/mol and lnA is 9.63 s-1.

关键词： Rare earths Bastnaesite Suspension roasting Thermal decomposition mechanism Reaction kinetics

Automatic recognition of landslides based on YOLOv7 and attention mechanism

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Journal of Mountain Science 2024年第8期21卷 2681-2695页

作者： SONG Yewei GUO Jie WU Gaofeng MA Fengshan li Fangrui Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Sciences Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Landslide disasters comprise the majority of geological incidents on slopes,posing severe threats to the safety of human lives and property while exerting a significant impact on the geological *** rapid identification of landslides is important for disaster prevention and control;however,currently,landslide identification relies mainly on the manual interpretation of remote sensing *** interpretation and feature recognition methods are time-consuming,labor-intensive,and challenging when confronted with complex ***,automatic landslide recognition has emerged as a pivotal avenue for future *** this study,a dataset comprising 2000 landslide images was constructed using open-source remote sensing images and *** YOLOv7 model was enhanced using data augmentation algorithms and attention *** optimization models were formulated to realize automatic landslide *** findings demonstrate the commendable performance of the optimized model in automatic landslide recognition,achieving a peak accuracy of 95.92%.Subsequently,the optimized model was applied to regional landslide identification,co-seismic landslide identification,and landslide recognition at various scales,all of which showed robust recognition ***,the model exhibits limitations in detecting small targets,indicating areas for refining the deep-learning *** results of this research offer valuable technical support for the swift identification,prevention,and mitigation of landslide disasters.

关键词： Deep learning Landslide detection Natural disasters Attention mechanism Remote sensing

Effects of nitrogen deposition on the carbon budget and water stress in Central Asia under climate change

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Journal of Arid Land 2024年第8期16卷 1118-1129页

作者： HAN Qifei XU Wei li Chaofan School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing 210044China

Atmospheric deposition of nitrogen(N)plays a significant role in shaping the structure and functioning of various terrestrial ecosystems ***,the magnitude of N deposition on grassland ecosystems in Central Asia still remains highly *** this study,a multi-data approach was adopted to analyze the distribution and amplitude of N deposition effects in Central Asia from 1979 to 2014 using a process-based denitrification decomposition(DNDC)*** showed that total vegetation carbon(C)in Central Asia was 0.35(±0.09)Pg C/a and the averaged water stress index(WSI)was 0.20(±0.02)for the whole *** N deposition led to an increase in the vegetation C of 65.56(±83.03)Tg C and slightly decreased water stress in Central *** of this study will expand both our understanding and predictive capacity of C characteristics under future increases in N deposition,and also serve as a valuable reference for decision-making regarding water resources management and climate change mitigation in arid and semi-arid areas globally.

关键词： carbon dynamics climate change grassland ecosystems nitrogen deposition water stress index

Acculturation and translation:Modern architectural heritage of Zhongshan Park in Xiamen from typological perspective

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Frontiers of Architectural Research 2024年第3期13卷 613-624页

作者： Xufang li Xiangpin Zhou Feifan Weng Fanzhuo Ding Zhenxin Yi Department of Landscape Architecture College of Architecture&Urban PlanningTongji UniversityShanghai 200092China Department of Landscape Architecture College of Landscape Architecture&ArtFujian Agriculture and Forestry UniversityFuzhou 350002China Academy of Art&Design Tsinghua UniversityBeijing 100084China Graduate School of Techno Design Kookmin UniversitySeoulRepublic of Korea

The modern architectural heritage is the core carrier of city’s historical inheritance and *** value is related to the spatial and temporal evolution of the urban landscape,along with the collective memory of society and transformation in public *** contradiction between high-speed urban construction and architectural heritage preservation has proliferated,and the problems of loss of heritage culture and fading of relics are very significant,but there is a lack of research on modern architectural *** study analysed indepth the artistic archetypes and evolutionary characteristics of the architecture of Zhongshan Park in Xiamen through field research and historical data collation,adopting the theory method of architectural ***,we analysed the architectural typology of Zhongshan Park in Xiamen and the process of acculturation and translation with foreign cultures,explored the motives of its formation and the cultural meanings of the public space embodied in *** on this,we proposed a sustainable development heritage approach for the modern architectural heritage of Zhongshan Park in *** results indicate that modern architectural art has inherited classical Chinese historical and cultural traditions and ideological *** unique characteristics reflect the spirit of the times and result from the gradual development of Western ***,it embodies a strong sense of national *** findings enrich the academic research on the cultural interaction between Chinese and Western architecture,offering valuable insights for the conservation and living heritage of modern architectural heritage in other regions.

关键词： Modern architectural heritage Acculturation translation Architectural typology Sun Yat-sen culture Xiamen Zhongshan Park

Ecology and risks of the global plastisphere as a newly expanding microbial habitat

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The Innovation 2024年第1期5卷 49-58页

作者： Changchao li Michael RGillings Chao Zhang Qinglin Chen Dong Zhu Jie Wang Kankan Zhao Qicheng Xu Polly Hangmei Leung Xiangdong li Jian liu ling Jin Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina Environment Research Institute Shandong UniversityQingdao 266237China State Key Laboratory of Marine Pollution City University of Hong KongKowloon TongHong KongChina ARC Centre of Excellence in Synthetic Biology Faculty of Science and EngineeringMacquarie UniversitySydneyNSW 2109Australia Key Laboratory of Urban Environment and Health Ningbo Urban Environment Observation and Research StationInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Institute of Soil and Water Resources and Environmental Science College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization Nanjing Agricultural UniversityNanjing 210095China Department of Health Technology and Informatics and Research Institute for Future Food The Hong Kong Polytechnic UniversityKowloonHong KongChina Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China

Plastic offers a new niche for microorganisms,the *** everincreasing emission of plastic waste makes it critical to understand the microbial ecology of the plastisphere and associated ***,we present a global fingerprint of the plastisphere,analyzing samples collected from freshwater,seawater,and terrestrial *** plastisphere assembles a distinct microbial community that has a clearly higher heterogeneity and a more deterministically dominated assembly compared to natural *** coexistence patterns—loose and fragile networks with mostly specialist linkages among microorganisms that are rarely found in natural habitats—are seen in the *** microbiomes generally have a great potential to metabolize organic compounds,which could accelerate carbon *** involved in the nitrogen cycle are also altered in the plastisphere,especially in freshwater plastispheres,where a high abundance of denitrifiers may increase the release of nitrite(aquatic toxicant)and nitrous oxide(greenhouse gas).Enrichment of animal,plant,and human pathogens means that the plastisphere could become an increasingly mobile reservoir of harmful *** findings highlight that if the trajectory of plastic emissions is not reversed,the expanding plastisphere could pose critical planetary health challenges.

关键词： reservoir mostly habitat

Strengthening-softening transition and maximum strength in Schwarz nanocrystals

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Nano Materials Science 2024年第3期6卷 320-328页

作者： Hanzheng Xing Jiaxi Jiang Yujia Wang Yongpan Zeng Xiaoyan li Center for Advanced Mechanics and Materials Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijing100084China Institute of High Performance Computing(IHPC) Agency for ScienceTechnology and Research(A*STAR)Singapore138632Singapore

Recently,a Schwarz crystal structure with curved grain boundaries(GBs)constrained by twin-boundary(TB)networks was discovered in nanocrystalline Cu through experiments and atomistic *** Cu with nanosized Schwarz crystals exhibited high strength and excellent thermal ***,the grainsize effect and associated deformation mechanisms of Schwarz nanocrystals remain ***,we performed large-scale atomistic simulations to investigate the deformation behaviors and grain-size effect of nanocrystalline Cu with Schwarz *** simulations showed that similar to regular nanocrystals,Schwarz nanocrystals exhibit a strengthening-softening transition with decreasing grain *** critical grain size in Schwarz nanocrystals is smaller than that in regular nanocrystals,leading to a maximum strength higher than that of regular *** simulations revealed that the softening in Schwarz nanocrystals mainly originates from TB migration(or detwinning)and annihilation of GBs,rather than GB-mediated processes(including GB migration,sliding and diffusion)dominating the softening in regular *** analyses of simulation data further showed that compared with those in regular nanocrystals,the GB-mediated processes in Schwarz nanocrystals are suppressed,which is related to the low volume fraction of amorphous-like GBs and constraints of TB *** smaller critical grain size arises from the suppression of GB-mediated processes.

关键词： Schwarz nanocrystal Curved grain boundary Atomistic simulation Grain size effect Maximum strength

Safety and efficacy of omalizumab for antihistamine-resistant chronic urticaria in children:a case series and literature review

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World Journal of Pediatrics 2024年第3期20卷 294-298页

作者： Wei-Fang Zhu Chen Wang Jian-Jun Qiao Lan-Juan li Department of Dermatology First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Chronic urticaria(CU)is a common skin disease characterized by the occurrence of wheals,with or without angioedema,lasting more than 6 *** prevalence of CU is about 0.7%[1],but higher in children,with an incidence of 1.38%[1].The occurrence of severe pruritus and unpredictable wheals may severely impact patients'quality of life,cause psychological problems,including sleep disorders and depression,and lead to economic burden due to limitation on daily life and work[2,3].

关键词： edema prevalence children

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