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The Optical Variability Properties of TeV Blazars

Research in Astronomy and Astrophysics 2024年第9期24卷 66-75页

作者： Zi-An Su Wen-Xin Yang xiang-tao zeng Le-Jian Ou Ze-Lin Li Jiang-He Yang Jun-Hui Fan Department of Physics School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Greater Bay Brand Center of the National Astronomical Data Center Guangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China College of Microelectronics Feicuihu Campus of Hefei University of TechnologyHefei 230601China College of Mathematics and Physics Science Hunan University of Arts and ScienceChangde 415000China

Variability is one of the typical observational properties of blazars and the spectral changes are usually associated with variability,although this kind of association is unclear *** this work,we used data from the Steward Observatory blazar monitoring program to investigate the optical variability properties including the short-term timescale,the brightness-dependent spectral property,the correlation between the the brightness variation and the polarization,and then estimate the Doppler factors based on the obtained short timescale to study the polarization property for a sample of 20 TeV *** analyses arrive at the following results:(1)The largest variation amplitude in R-band,ΔR_(M),covers a range from ΔR_(M)=0.29 mag(1ES 2344+514)to ΔR_(M)=4.66 mag(3C 279).(2)Intra-day variability was found from five sources with timescales from 0.14 day for S50716+714 to 0.98 day for PKS *** sources show spectra that are bluer when they become brighter,suggesting a common bluer-when-brighter property.(3)The plot of the polarization versus estimated Doppler factor is consistent with the Doppler factor dependent formula of polarization.(4)The largest polarization is correlated with the largest optical variation,suggesting that the high polarization and high amplitude variation are both the indicator of beaming effect.

关键词： galaxies:active galaxies:jets radiation mechanisms:non-thermal

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Parameterization of height-diameter and crown radius-diameter relationships across the globe

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Journal of Plant Ecology 2024年第2期17卷 36-48页

作者： xiang Song Jinxu Li Xiaodong zeng International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of Mathematics and Statistics North China University of Water Resources and Electric PowerZhengzhou 450046China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The tree height-diameter at breast height(H-DBH)and crown radius-DBH(CR-DBH)relationships are key for forest carbon/biomass estimation,parameterization in vegetation models and vegetation-atmosphere *** the H-DBH relationship has been widely investigated on site or regional scales,and a few of studies have involved CR-DBH relationships based on plot-level data,few studies have quantitatively verifed the universality of these two relationships on a global *** study evaluated the ability of 29 functions to ft the H-DBH and CR-DBH relationships for six different plant functional types(PFTs)on a global scale,based on a global plant trait *** showed that most functions were able to capture the H-DBH relationship for tropical PFTs and boreal needleleaf trees relatively accurately,but slightly less for temperate PFTs and boreal broadleaf trees(BB).For boreal PFTs,the S-shaped Logistic function ftted the H-DBH relationship best,while for temperate PFTs the Chapman-Richards function performed *** tropical needleleaf trees,the fractional function of DBH satisfactorily captured the H-DBH relationship,while for tropical broadleaf trees,the Weibull function and a composite function of fractions were the best *** CR-DBH,the ftting capabilities of all the functions were comparable for all PFTs except *** Logistic function performed best for two boreal PFTs and temperate broadleaf trees,but for temperate needleleaf trees and two tropical PFTs,some exponential functions demonstrated higher *** work provides valuable information for parameterization improvements in vegetation models and forest feld investigations.

关键词： tree height diameter at breast height crown radius ftting function parameterization vegetation model

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Multicolor circularly polarized phosphorescence of axially chiral binuclear platinum(Ⅱ) complexes

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Science China Chemistry 2024年第11期67卷 3757-3766页

作者： Jintong Song Rui zeng Hui Xiao Hailiang Ni Zong-xiang Xu Haifeng xiang College of Chemistry and Materials Science Sichuan Normal University Department of Chemistry Southern University of Science and Technology College of Chemistry Sichuan University

D-A charge transfer, including through-bond charge transfer and through-space charge transfer between two different electron donors（D） and electron acceptors（A）, is a fundamental and powerful tool to tune the optical properties of organic dyes. Herein,we demonstrate a unique strategy to tune phosphorescence and circularly polarized luminescence properties of axially chiral binuclear Pt（Ⅱ） complexes through long-range charge transfer, even though these molecules have two totally identical segments on either side of the chiral core. The presence of axial chirality would break not only the symmetry of molecular structure and π-conjugation system but also the symmetry of charge distribution for long-range charge transfer. These binaphthyl-based Pt（Ⅱ）complexes bearing coordinated atoms far away from chiral axis exhibit no Pt-Pt interactions but colorful concentrationdependent phosphorescence with quantum yield up to 86.4% and could be applied as emitters in highly efficient solutionprocessed organic light-emitting diodes to achieve luminance, luminance efficiency, power efficiency, external quantum efficiency, and asymmetry factor up to 8.94 × 10～3cd m-2, 41.9 cd A-1, 18.8 lm W-1, 12.6% and 2.98 × 10-3, respectively. Therefore,the present work affords a new and simple way to utilize the inherently asymmetric advantage of chirality for the design of D-Abased organic dyes.

关键词： Pt(II) complexes organic light-emitting diodes circularly polarized phosphorescence axial chirality

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Wetting-drying effect on the strength and microstructure of cementphosphogypsum stabilized soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1049-1058页

作者： Lingling zeng Xia Bian Jiaxing Weng tao Zhang College of Civil Engineering Zhejiang University of TechnologyHanzhou310014China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China Jiangsu Water Source Company Ltd.of the Eastern Route of the South-to-North Water Diversion Project Nanjing210000China Power China Zhongnan Engineering Corporation Limited Changsha410027China

Phosphogypsum has often been used as an effective and environmentally friendly binder for partial replacement of cement,improving the engineering properties of slurries with high water ***,the influence of phosphogypsum on the physicomechnical properties of stabilized soil subjected to wettingedrying cycles is not well understood to *** this study,the effect of phosphogypsum on the durability of stabilized soil was studied by conducting a series of laboratory experiments,illustrating the changes in mass loss,pH value and unconfined compressive strength(qu)with wettingdrying *** test results showed that the presence of phosphogypsum significantly restrained the mass loss in the early stage(lower than the 4th cycle),which in turn led to a higher qu of stabilized soil than that without *** the 4th cycle,a sudden increase in mass loss was observed for stabilized soil with phosphogypsum,resulting in a significant drop in qu to a value lower than those without phosphogypsum at the 6th *** addition,the qu of stabilized soils correlated well with the measured soil pH irrespective of phosphogypsum content for all wettingedrying *** to the microstructure observation via scanning electron microscope(SEM)and X-ray diffraction(XRD)tests,the mechanisms relating the sudden loss of qu for the stabilized soils with phosphogypsum after the 4th wetting-drying cycle are summarized as follows:(i)the disappearance of ettringite weakening the cementation bonding effect,(ii)the generation of a larger extent of microcrack,and(iii)a lower pH value,in comparison with the stabilized soil without phosphogypsum.

关键词： Wetting-drying Phosphogypsum Microstructure Durability

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Study on theoretical model for electrical explosion resistivity of Al/Ni reactive multilayer foil

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Defence Technology（防务技术） 2024年第2期32卷 348-356页

作者： Zehao Wang tao Wang Pengfei Xue Mingyu Li Qingxuan zeng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China China Ship Development and Design Center Wuhan 430064China

Al/Ni reactive multilayer foil(RMF)possesses excellent comprehensive properties as a promising substitute for traditional Cu bridge.A theoretical resistivity model of Al/Ni RMF was developed to guide the optimization of ***/Ni RMF with different bilayer thicknesses and bridge dimensions were prepared by MEMS technology and electrical explosion tests were carried *** to physical and chemical reactions in bridge,the electrical explosion process was divided into 5 stages:heating of condensed bridge,vaporization and diffusion of Al layers,intermetallic combination reaction,intrinsic explosion,ionization of metal gases,which are obviously shown in measured voltage *** of interface and grain boundary scattering on the resistivity of film metal were *** on variations of substance and state,the resistivity was developed as a function of temperature at each *** explosion curves were calculated by this model at different bilayer thicknesses,bridge dimensions and capacitor voltages,which showed an excellent agreement with experimental ones.

关键词： Al/Ni reactive multilayer foil Electrical explosion Resistivity model Phase transition Calculation

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The Early Mesozoic NE-SW Extensional Model and Exhumation Processes at the Southeastern Margin of the Central Asian Orogenic Belt: Insights from the Strain and Kinematic Vorticity Analysis of the Sonid Zuoqi Ductile Detachment Zone

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ACTA GEOLOGICA SINICA-ENGLISH EDITION 2024年第5期98卷 1141-1153页

作者： Li, Jianbo Song, Zhijie Lei, Hengcong zeng, tao East China Univ Technol Nanchang 344000 Peoples R China

The Sonid Zuoqi ductile detachment zone is located at the southeastern margin of the Central Asian orogenic belt (CAOB), striking EW and dipping to the S. The major rock type of the Sonid Zuoqi ductile detachment zone is mylonite derived from granite. The sequence of mylonite features is: (1) S and C foliations of mylonite, and (2) extensional crenulation cleavage (ecc) or C and the kinematic vorticity (Wk) value changed from 0.70 to 0.95 and from 0.37 to 0.69, respectively; the strain type of the mylonites within the Sonid Zuoqi ductile detachment zone is compressional to planar strain. The strong deformation mylonite and Halatu plutons yielded a zircon U-Pb age of 244 Ma and a zircon (U-Th)/He age of 214 Ma, respectively. Based on the strain and kinematic vorticity analysis, together with the zircon U-Pb and zircon (U-Th)/He ages and the regional tectonic background, the study area experienced three stage evolution: tangential simple-shear (244 Ma), simple-shear-dominated general shear represented by upper crustal extension (224 Ma) and pure-shear-dominated general shear represented by the Halatu pluton doming (214 Ma), which constrained the early Mesozoic NE-SW crustal extension at the southeastern margin of the CAOB. This NE-SW extension probably originated from the post-orogenic extensional collapse of the CAOB, subsequent exhumation being controlled by the far afield effects of the closure of the Mongol-Okhotsk belt.

关键词： strain simple shear pure shear kinematic vorticity ductile detachment zone METAMORPHIC CORE COMPLEX ANGLE NORMAL FAULTS INNER-MONGOLIA CRUSTAL GROWTH NORTH CHINA EVOLUTION ORIGIN REGION AGE

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Achieving single-cell-resolution lineage tracing in zebrafish by continuous barcoding mutations during embryogenesis

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Journal of Genetics and Genomics 2024年第9期51卷 947-956页

作者： Zhan Liu Hui zeng Huimin xiang Shanjun Deng Xionglei He State Key Laboratory of Biocontrol School of Life SciencesSun Yat-Sen UniversityGuangzhouGuangdong 510275China

Unraveling the lineage relationships of all descendants from a zygote is fundamental to advancing our understanding of developmental and stem cell ***,existing cell barcoding technologies in zebrafish lack the resolution to capture the majority of cell divisions during embryogenesis.A recently developed method,a substitution mutation-aided lineage-tracing system(SMALT),successfully reconstructed high-resolution cell phylogenetic trees for Drosophila ***,we implement the SMALT system in zebrafish,recording a median of 14 substitution mutations on a one-kilobase-pair barcoding sequence for one-day post-fertilization *** this system,we reconstruct four cell lineage trees for zebrafish fin cells,encompassing both original and regenerated *** tree consists of hundreds of internal nodes with a median bootstrap support of 99%.Analysis of the obtained cell lineage trees reveals that regenerated fin cells mainly originate from cells in the same part of the *** multiple times sampling germ cells from the same individual,we show the stability of the germ cell pool and the early separation of germ cell and somatic cell *** system offers the potential for reconstructing high-quality cell phylogenies across diverse tissues,providing valuable insights into development and disease in zebrafish.

关键词： Lineage tracing Cellular barcoding Zebrafishcell phylogeny Fin regeneration Germcell lineage

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Gbps key rate passive-state-preparation continuous-variable quantum key distribution within an access-network area

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Photonics Research 2024年第7期12卷 1485-1493页

作者： FEIYU JI PENG HUANG tao WANG XUEQIN JIANG GUIHUA zeng State Key Laboratory of Advanced Optical Communication Systems and Networks Center for Quantum Sensing and Information ProcessingSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Research Center for Quantum Sciences Shanghai 201315China Hefei National Laboratory Hefei 230088China College of Information Science and Technology Donghua UniversityShanghai 201620China

The conventional Gaussian-modulated coherent-state quantum key distribution(QKD) protocol requires the sender to perform active modulations based on a true random number generator. Compared with it, the passive-state-preparation(PSP) continuous-variable quantum key distribution(CVQKD) equivalently performs modulations passively by exploring the intrinsic field fluctuations of a thermal source, which offers the prospect of chip integration QKD with low cost. In this paper, we propose and experimentally demonstrate a high-rate PSP-CVQKD scheme within an access-network area using high-bandwidth detectors in a continuous wave encoding and decoding way. By proposing effective methods for suppressing the noises during the PSP process and polarization multiplexing to decrease the photon leakage noises, we realize the high-intensity local oscillator transmission, thereby achieving coherent detection with high efficiency, low noise, and high bandwidth. The secure key rates over transmission distance of 5.005 km with and without consideration of the finite-size effect are 273.25 Mbps and 1.09 Gbps. The use of the PSP method boosts the asymptotic secret key rate of CVQKD to Gbps level for the first time, to our knowledge, within the range of the access network, which provides an effective and secure key distribution strategy for high-speed quantum cryptography access communication.

关键词： passive network distribution

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Machine Learning-Aided Data Analysis in Single-Protein Conductance Measurement with Electron Tunneling Probes

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Chinese Journal of Chemistry 2024年第1期42卷 67-72页

作者： Yuxin Yang tao Jiang Ye Tian Biaofeng zeng Longhua Tang State Key Laboratoryof Extreme Photonics and Instrumentation College of Optical Science and EngineeringZhejiang University HangzhouZhejiang 310027China Nanhu Brain-computer Interface Institute HangzhouZhejiang 311100China State Key Laboratory of Fluid Power and Mechatronic Systems College of Mechanical EngineeringZhejiang University HangzhouZhejiang 310027China

The electrical tunneling sensors have excellent potential in the next generation of single-molecule measurement and sequencing technologies due to their high sensitivity and spatial resolution *** tunneling signals that have been measured at a high sampling rate may provide detailed molecular *** the extraordinarily large amount of data that has been gathered,it is still difficult to correlate signal transformations with molecular processes,which creates great obstacles for signal *** learning is an effective tool for data analysis that is currently gaining more *** has demonstrated promising results when used to analyze data from single-molecule electrical *** order to extract meaningful information from raw measurement data,we have combined intelligent machine learning with tunneling electrical *** the purpose of analyzing tunneling electrical signals,we investigated the clustering approach,which is a classic algorithm in machine learning.A clustering model was built that combines the advantages of hierarchical clustering and Gaussian mixture model ***,customized statistical algorithms were *** has been proven to efficiently gather molecular information and enhance the effectiveness of data analysis.

关键词： Tunneling sensor Single-molecule measurement Machine learning Single-protein conductance Molecular electrochemistry Nanotechnology Molecular electronics

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A folic acid-decorated nanoparticles loaded JQ1 for oral squamous cell carcinoma therapy

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Chinese Chemical Letters 2024年第3期35卷 332-336页

作者： Dequan zeng Zhongkai Ma Xin Zan Ting Luo xiang Wang xiang Gao xianghui Fu School of Health Management Xihua UniversityChengdu 610039China State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China College of StomatologySichuan UniversityChengdu 610041China Department of Neurosurgery and Institute of Neurosurgery State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalWest China Medical SchoolSichuan University and Collaborative Innovation Center for BiotherapyChengdu 610041China Breast Disease Center Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China

Oral squamous cell carcinoma(OSCC)is known as one of the most malignant tumors with high recurrence and fatality *** poor tumor-targeting ability of traditional chemotherapeutic drugs has been a grand challenge for anti-OSCC *** that,a large quantity of tumor associated macrophages in OSCC tissues further diminish the anti-tumor effects of these ***,we produced a therapeutic nano drug delivery system(FA-PEG-PLA-JQ1)through encapsulating JQ1[a small-molecule inhibitor of bromodomain containing protein 4(BRD4)]into the folic acid(FA)-modified nanoparticle(PEG-PLA),which could prolong the half-life of JQ1 and target the tumor *** then,JQ1 released from this nanoparticle could prevent OSCC growth inducing tumor cell apoptosis,inhibiting tumor angiogenesis and the polarization of M2 type *** conclusion,our date demonstrated the therapeutic benefits of FA-PEG-PLA-JQ1 against OSCC in vivo or in vitro,which could be a novel treatment strategy for OSCC in coming days.

关键词： Folic acid Nanoparticles JQ1 Oral squamous cell carcinoma Macrophages

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