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Detection of UAV Target Based on Continuous Radon Transform and matched Filtering Process for Passive Bistatic Radar

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Journal of Beijing Institute of Technology 2024年第1期33卷 9-18页

作者： Luo Zuo Yuefei Yan Jun wang xin Sang Yan wang Dongming Ge Lihao Ping Zhihai wang Congsi wang Guangzhou Institute of Technology Xidian UniversityGuangzhou 510555China National Laboratory of Radar Signal Processing Xidian UniversityXi’an710071China School of Information and Control Engineering Xi’an University of Architecture and TechnologyXi’anShaanxi 710055China CETC Wuhu Diamond Aircraft manufacturing Co. LtdWuhuAnhui 241000China Beijing Space Vehicle General Design Department Beijing 100094China CETC No.38 Research Institute Hefei 230088China

Long-time integration technique is an effective way of improving target detection performance for unmanned aerial vehicle(UAV)in the passive bistatic radar(PBR),while range migration(Rm)and Doppler frequency migration(DFm)may have a major effect due to the target *** paper proposed an innovative long-time coherent integration approach,regarded as Continuous Radon-matched filtering process(CRmFP),for low-observable UAV target in passive bistatic *** not only mitigates the Rm by collaborative research in range and velocity dimensions but also compensates the DFm and ensures the coherent integration through the matched filtering process(mFP).Numerical and real-life data following detailed analysis verify that the proposed method can overcome the Doppler mismatch influence and acquire comparable detection performance.

关键词： passive bistatic radar unmanned aerial vehicle long-time coherent integration Radon-matched filtering process

Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

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Biomedical and Environmental Sciences 2024年第2期37卷 196-203页

作者： wang Dan Dan wang An xin ZHANG Xiao Li WEI Wen Bin WU Shou Ling ZHAO xing Quan Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China China National Clinical Research Center for Neurological Diseases Beijing 100070China Beijing Tongren Eye Center Beijing Key Laboratory of Ophthalmology and Visual ScienceBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Department of Cardiology Kailuan HospitalTangshan 063001HebeiChina

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population *** study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular *** We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or *** regression was used to analyze the relationship between retinal metrics and cognitive *** stratified by different vascular statuses were also *** RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(Pmall vessel change in RNFL and CI should be investigated in the future.

关键词： Retinal nerve fiber layer Cognitive impairment Polyvascular abnormality

An Assembly of Pyrano[3,2-b]indol-2-ones via NHC-Catalyzed[3+3]Annulation of Indolin-3-ones with Ynals

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Chinese Journal of Chemistry 2024年第13期42卷 1487-1492页

作者： Xia wang Shulei Zhang Shao-Jie wang Hao An Xiaolan xin Haonan Lin Zhifeng Tu Shenci Lu Frontiers Science Center for Flexible Electronics(FSCFE) Shaanxi Institute of Flexible Electronics(SIFE)&Shaanxi Instituteof Biomedical Materials and Engineering(SiBME)Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China School of Chemistry and Chemical Engineering Northwestern Polytechnical University(NPU)127 West Youyi RoadXi'anShaanxi 710072China

We report herein an unprecedented N-heterocyclic carbene-catalyzed formal[3+3]annulation of ynals with N-Ts indolin-3-ones under the oxidation condition affording the functionalized pyrano[3,2-b]*** alkynyl acylazoliums via the combination of a carbene with ynals in the presence of oxidate proved to be the important intermediates for the success of this *** method features a broad substrate scope and mild conditions,including axially chiral skeletons with suitable substitutions.

关键词： N-Heterocyclic carbene Annulation Organocatalysis Atropisomerism Carbazole Aldehydes Heterocycles Asymmetric catalysis

Non-transcriptional regulatory activity of SmAX1 and SmXL2 mediates karrikin-regulated seedling response to red light in Arabidopsis

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molecular Plant 2024年第7期17卷 1054-1072页

作者： Wenwen Chang Qiao Qiao Qingtian Li xin Li Yanyan Li Xiahe Huang Yingchun wang Jiayang Li Bing wang Lei wang Key Laboratory of Seed Innovation Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuangHebei050021China Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyThe Innovative Academy for Seed DesignChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing 100049China Yazhouwan National Laboratory SanyaHainan 572024China

Karrikins and strigolactones govern plant development and environmental responses through closely related signaling *** transcriptional repressor proteins SUPPRESSOR OF mAX21(SmAX1),SmAX1-like2(SmXL2),and D53-like SmXLs mediate karrikin and strigolactone signaling by directly binding downstream genes or byinhibiting the activities of transcription *** this study,we characterized the non-transcriptional regulatory activities of SmXL proteins in *** discovered that SmAX1 and SmXL2 with mutations in their ethylene-responsefactor-associated amphiphilic repression(EAR)motif had undetectable or weak transcriptional repression activities but still partially rescued the hypocotyl elongation defects and fully reversed the cotyledon epinasty defects of the smax1 smxl2 ***1 and SmXL2 directly interact with PHYTOCHROmE INTERACTION FACTOR4(PIF4)and PIF5 to enhance their protein stability by interacting with phytochrome B(phyB)and suppressing the association of phyB with PIF4 and *** karrikin-responsive genes were then identified by treatment with GR24ent-ssa,GR24 analog showing karrikin ***,INDOLE-3-ACETIC ACID INDUCIBLE 29(IAA29)expression was repressed by GR24^(ent-5D)streatment in a PIF4-and PIF5-dependent and EARindependent manner,whereas KARRIKIN UPREGULATED F-BOX 1(KUF1)expression was induced in a PIF4-and PIF5-independent and EAR-dependent ***,the non-transcriptional regulatory activity of SmAX1,which is independent of the EAR motif,had a global effect on gene *** together,these results indicate that non-transcriptional regulatory activities of SmAX1 and SmXL2 mediate karrikin-regulated seedling response to red light.

关键词： karrikin signaling SmAX1 and SmXL2 non-transcriptional repression activity PIF4 and PIF5 gene expression red light

modification of BCC phase and the enhanced reversible hydrogen storage properties of Ti-V-Fe-mn alloys with varied V/Fe ratios

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China Foundry 2024年第5期21卷 546-554页

作者： Xiang-feng ma xin Ding En-lai Liu Rui-run Chen xin-xiu wang Yong Zhang and Jing-jie Guo National Key Laboratory for Precision Hot Processing of metals Harbin Institute of TechnologyHarbin 150001China School of materials Science and Engineering Shandong University of Science and TechnologyQingdao 266500ShandongChina AECC Harbin Dongan Engine Co.Ltd.Harbin 150001China

Ti-V-based alloys are proved of huge potential in storing hydrogen,but the incomplete reversible hydrogen storage capacity caused by overstability of V hydride has limited the large-scale *** this study,Ti_(32)V_(40+x)Fe_(23-x)mn_(5)(x=0,4,8,12,at.%)alloys were designed,and the effects of V/Fe ratio on phase constitution and hydrogen storage properties were *** main phase of the alloys is body-centered cubic(BCC)phase,and the lattice constants of the BCC phase decrease with the decrease of V/Fe ***,C14 Laves phase exists in alloys with a Fe content of 19at.%to 23at.%.For hydrogenation,the C14 Laves phase can accelerate the hydrogen absorption rate,but the hydrogen absorption capacity is *** the decrease of V/Fe ratio,the hydride gradually *** to its large lattice constant and high hydrogen absorption phase content,the Ti_(32)V_(52)Fe_(11)mn_(5)alloy shows the most enhanced hydrogen storage properties with hydrogenation and dehydrogenation capacities of 3.588wt.%at 298 K and 1.688wt.%at 343 K,*** hydrogen absorption capacity of this alloy can be reserved to 3.574wt.%after 20 cycles of hydrogen absorption and desorption.

关键词： hydrogen storage Ti-based alloy lattice constant BCC phase

Cloning, Characterization and Transformation of methyltransferase 2a Gene (Zmet2a) in maize (Zea mays L.)

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1767-1779页

作者： xin Qi Yu wang xing Zhang Xiaoshuang Wei xinyang Liu Zhennan wang Zhenhui wang Fenglou Ling Faculty of Agronomy Jilin Agricultural UniversityChangchun130118China Rice Research Center Jilin Agricultural UniversityChangchun130118China

DNA methylation is an important epigenetic regulatory mechanism,it regulates gene expression by recruiting proteins involved in gene repression or by inhibiting the binding of transcription factor(s)to *** this study,a novel methyltransferase 2a gene(Zmet2a)was cloned in maize and identiﬁed by polymerase chain reaction-base(PCR-base)using a bioinformatics *** Zmet2a cDNA sequence is 2739 bp long and translates to 912 amino acid *** Zmet2a protein revealed that it contains BAH and CHROmO structural domains,is a non-transmembrane protein that is hydrophilically unstable,and has no signal peptide ***,we veriﬁed the biological roles of Zmet2a using transgenic Arabidopsis overexpressing Zmet2a and Zmet2a-knockout *** Zmet2a Arabidopsis thaliana showed highly signiﬁcant advancement inﬂowering time,and Zmet2a-knockout maize showed advancement inﬂowering time,with signiﬁcant changes in several ***,these report the role of Zmet2a in the regulation ofﬂowering time,which will lay a foundation for revealing the biological function and epigenetic regulation mechanism of Zmet2a in the growth,development andﬂowering of maize.

关键词： DNA methylation methyltransferase Zea mays L ﬂowering time functional analysis

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-Qing Li Wen-Hao wang Yuan-Da Su Jun-xin Guo Xiao-ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation microcracked porous background FB-WIFF Elastic scattering Squirt flow

Delving into the dissimilarities in electrochemical performance and underlying mechanisms for sodium and potassium ion storage in N-doped carbon-encapsulated metallic Cu_(2)Se nanocubes

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Journal of Energy Chemistry 2024年第8期95卷 336-347,I0008页

作者： xinyu wang Yanan Xu Xiaofeng Liu Lei Tan Huaiqiang Gu xin Du Dan Li College of Chemistry Zhengzhou UniversityZhengzhou 450001HenanChina Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001HenanChina Institute of Theoretical Physics Lanzhou UniversityLanzhou 730000GansuChina School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000GansuChina Key Laboratory of Advanced Energy materials Chemistry(ministry of Education) College of ChemistryNankai UniversityTianjin 300071China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830046XinjiangChina

The large volumetric variations experienced by metal selenides within conversion reaction result in inferior rate capability and cycling stability,ultimately hindering the achievement of superior electrochemical ***,metallic Cu_(2)Se encapsulated with N-doped carbon(Cu_(2)Se@NC)was prepared using Cu_(2)O nanocubes as templates through a combination of dopamine polymerization and hightemperature *** unique nanocubic structure and uniform N-doped carbon coating could shorten the ion transport distance,accelerate electron/charge diffusion,and suppress volume variation,ultimately ensuring Cu_(2)Se@NC with excellent electrochemical performance in sodium ion batteries(SIBs)and potassium ion batteries(PIBs).The composite exhibited excellent rate performance(187.7 mA h g^(-1)at 50 A g^(-1)in SIBs and 179.4 mA h g^(-1)at 5 A g^(-1)in PIBs)and cyclic stability(246,8 mA h g^(-1)at 10 A g^(-1)in SIBs over 2500 cycles).The reaction mechanism of intercalation combined with conversion in both SIBs and PIBs was disclosed by in situ X-ray diffraction(XRD)and ex situ transmission electron microscope(TEm).In particular,the final products in PIBs of K_(2)Se and K_(2)Se_(3)species were determined after discharging,which is different from that in SIBs with the final species of Na_(2)*** density functional theory calculation showed that carbon induces strong coupling and charge interactions with Cu_(2)Se,leading to the introduction of built-in electric field on heterojunction to improve electron ***,the theoretical calculations discovered that the underlying cause for the relatively superior rate capability in SIBs to that in PIBs is the agile Na~+diffusion with low energy barrier and moderate adsorption *** findings offer theoretical support for in-depth understanding of the performance differences of Cu-based materials in different ion storage systems.

关键词： Cu_(2)Se nanocubes DFT calculations Ion storage mechanism Potassium ion batteries Sodium ion batteries

An Innovative Coupled Common-Node Discrete Element method-Smoothed Particle Hydrodynamics model Developed with LS-DYNA and Its Applications

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China Ocean Engineering 2024年第3期38卷 467-482页

作者： SHEN Zhong-xiang wang Wen-qing XU Cheng-yue LUO Jia-xin LIU Ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this study,a common-node DEm-SPH coupling model based on the shared node method is proposed,and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics(DS-SPH)method is developed using LS-DYNA *** DEm and SPH are established on the same node to create common-node DEm-SPH particles,allowing for fluid–structure *** simulations of various scenarios,including water entry of a rigid sphere,dam-break propagation over wet beds,impact on an ice plate floating on water and ice accumulation on offshore structures,are *** interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also *** results are compared with available data to verify the proposed coupling ***,the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.

关键词： common-node DEm-SPH fluid-structure interaction discrete element method smoothed particle hydrodynamics