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Research on Pulsar Time Steered Atomic Time Algorithm Based on DPLL

Research in Astronomy and Astrophysics 2024年第3期24卷 237-248页

作者： Ze-Hao Zheng Yang Liu Dan shen Fan Feng Jiu-Long Liu Yue-Xin Ma Xiang-wei Zhu School of Electronic and Communication Engineering Sun Yat-sen UniversityShenzhen 518107China School of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107China School of Systems Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

In today’s society,there is a wide demand for high-precision and high-stability time service in the fields of electric power,communication,transportation and *** present,the time standard in various countries is mainly based on atomic clocks,but the frequency drift of atomic clocks will affect the long-term stability *** with atomic clocks,millisecond pulsars have better long-term stability and can complement with the excellent short-term stability of atomic *** order to improve the long-term stability of the atomic timescale,and then improve the timing accuracy,this paper proposes an algorithm for steering the atomic clock ensemble(ACE)by ensemble pulsar time(EPT)based on digital phase locked loop(DPLL).First,the ACE and EPT are generated by the ALGOS algorithm,then the ACE is steered by EPT based on DPLL to calibrate the long-term frequency drift of the atomic clock,so that the generated steered atomic time follows both the short-term stability characteristics of ACE and the long-term stability characteristics of EPT,and finally,the steered atomic time is used to calibrate the local cesium *** experimental results show that the long-term stability of atomic time after steering is improved by 2 orders of magnitude compared with that before steering,and the daily drift of a local cesium clock after calibration is less than 9.47 ns in 3 yr,3 orders of magnitude higher than that before calibration on accuracy.

关键词： (stars) pulsars general-time-methods data analysis-instabilities

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STING mediates microglial pyroptosis via interaction with NLRP3 in cerebral ischaemic stroke

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Stroke & Vascular Neurology 2024年第2期9卷 153-164页

作者： Wenyu Li Nan shen Lingqi Kong hongmei Huang Xinyue Wang Yan Zhang Guoping Wang Pengfei Xu wei Hu Department of Neurology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhuiChina

background Ischaemia-evoked neuroinflammation is a critical pathogenic event following ischaemic *** D(GSDMD)-associated pyroptosis represents a type of inflammation-associated programmed cell death,which can exacerbate neuroinflammatory responses and brain *** of interferon genes(STING)was recently described as a vital innate immune adaptor protein associated with ***,the regulatory effects of STING on microglial pyroptosis post-stroke have not been well *** STING-knockout and wild-type(WT)mice were subjected to middle cerebral artery occlusion(MCAO).STING small interfering RNA(siRNA)was transfected into BV2 cells before oxygen-glucose deprivation/reoxygenation(OGD/R).STING-overexpressing adeno-associated virus(AAV)and NOD-like receptor family pyrin domain containing 3(NLRP3)siRNA were administered by stereotaxic injection.2,3,5-Triphenyl tetrazolium chloride(TTC)staining,TdT-mediated dUTP nick end labeling(TUNEL)staining,Fluoro-Jade C(FJC)staining,neurobehavioural tests,immunohistochemistry,cytokine antibody array assay,transmission electron microscopy,immunoblot,Enzyme-linked immunosorbent assay(ELISA)and quantitative real-time polymerase chain reaction(qRT-PCR)were carried ***-immunoprecipitation assays were used to investigate the interplay between STING and *** STING expression was increased after MCAO and mainly detected on *** deletion alleviated brain infarction,neuronal damage and neurobehavioural impairment in mice subjected to *** knockout suppressed microglial activation and the secretion of inflammatory chemokines,accompanied by mitigation of microglial *** upregulation of microglial STING by AAV-F4/80-STING aggravated brain injury and microglial ***,co-immunoprecipitation showed that STING bound to NLRP3 in *** of NLRP3 siRNA reversed AAV-F4/80-STING-induced deterioration of microglial pyropt

关键词： NLRP3 cerebral inflammation

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A direct polymeric carbon nitride/tungsten oxide Z-scheme heterostructure for efficient photocatalytic hydrogen generation via reforming of plastics into value-added chemicals

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Rare Metals 2024年第8期43卷 3771-3783页

作者： Rui-Zhe Wang Zhi Lin Yi-Qing Wang Kai-Ni Zhang Ge-hong Zhang Jie Zhang Samuel S.Mao Shao-Hua shen International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an 710049China School of Civil and Architecture Engineering Xi'an Technological UniversityXi'an 710021China Department of Mechanical Engineering University of California at BerkeleyBerkeleyCA94720USA

To promote charge transfer and separation for efficient photocatalysis,a direct Z-scheme heterostructure was constructed by coupling polymeric carbon nitride(PCN) and WO_(3).Interestingly,the obtained PCN/WO_(3)Z-scheme heterostructure could photocataly tic ally produce hydrogen and value-added chemicals(e.g.,formate and acetate) by reforming of plastic polylactic acid(PLA) in alkaline aqueous *** optimizing WO_(3) contents and reaction conditions,the obtained PCN/WO_(3)heterostructure exhibits much increased photocatalytic activity for PLA photoreforming under visible light,with hydrogen evolution rate reaching 402.90 μmol·g~(-1)·h~(-1),which is 3.5 times that of *** is revealed that the Z-scheme charge transfer between PCN and WO_(3) mainly contributes to the promoted charge separation and thus the improved photocatalytic ***,with h+and·OH experimentally evidenced as the predominant active species,a possible reaction pathway for the reforming of PLA into value-added chemicals(e.g.,formate and acetate)over PCN/WO_(3) Z-scheme heterostructure is cleared by monitoring the reaction intermediates and *** work paves a carbon neutrality and scalable route toward the synergistical production of hydrogen and value-added chemicals by utilizing and recycling plastic waste.

关键词： Carbon nitride Z-scheme heterojunction Plastic waste conversion Photocatalytic H_(2)production Value-added chemicals

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Symmetry breaking of highly symmetrical nanoclusters for triggering highly optical activity

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Fundamental Research 2024年第1期4卷 63-68页

作者： Xiao wei Hao Li honglei shen Chuanjun Zhou Shuxin Wang Xi Kang Manzhou Zhu Department of Chemistry and Centre for Atomic Engineering of Advanced Materials Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationInstitutes of Physical Science and Information Technology and Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials.Anhui UniversityHefei 230601China

Developing new approaches to fulfill the enantioseparation of nanocluster racemates and construct cluster-based nanomaterials with optical activity remains highly desired in cluster science,because it is an essential prerequisite for fundamental research and extensive applications of these *** herein propose a strategy termed“active-site exposing and partly re-protecting”to trigger the symmetry breaking of highly symmetrical nanoclusters and to render cluster crystals optically *** vertex PPh_(3)of the symmetrical Ag_(29)(SSR)_(12)(PPh_(3))_(4)(SSR=1,3-benzenedithiol)nanocluster was firstly dissociated in the presence of counterions with large steric hindrance,and then the exposed Ag active sites of the obtained Ag_(29)(SSR)_(12)nanocluster were partly re-protected by Ag^(+),yielding an Ag_(29)(SSR)_(12)-Ag_(2)nanocluster with a symmetry-breaking ***_(29)(SSR)_(12)-Ag_(2)followed a chiral crystallization mode,and its crystal displayed strong optical activity,derived from CD and CPL ***,this work presents a new approach(i.e.,active-site exposing and partly re-protecting)for the symmetry breaking of highly symmetrical nanoclusters,the enantioseparation of nanocluster racemates,and the achievement of highly optical activity.

关键词： Atomically precise nanocluster Symmetry breaking Enantioseparation Circularly polarized luminescent Photoluminescence

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Global epidemiology of mental disorder in atrial fibrillation between 1998-2021:A systematic review and meta-analysis

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World Journal of Psychiatry 2024年第1期14卷 179-193页

作者： Shuai Zhang Na Zhang Liu Liu Wang Zheng Zi-Lin Ma Si-Yu Qiao Ying-Li Zhao Yi-hong wei Gang Wu Qiu-Ting Yu Bing Deng Lin shen Department of Cardiology LongHua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200032China Department of Dermatology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China

BACKGROUND As the burden of mental disorders among patients with atrial fibrillation(AF)increases,researchers are beginning to pay close attention to the risk and prevalence of these *** studies have independently analyzed the risk of comorbidity with depression and anxiety in patients with AF,no study has systematically focused on the global epidemiology of these two mental *** To explore the prevalence of depression and anxiety in patients with *** Five databases were searched from their date of establishment until January *** studies reporting the comorbidity of AF with depression and anxiety,were included in this *** information,such as the first author/publication year,study year,study type,and prevalence of depression and anxiety,were *** SE 15.1 was used to analyze the ***,meta-regression,and sensitivity analyses were performed to estimate study *** After a thorough search,26 studies were identified and included in this *** prevalence rates of depression and anxiety in adults with AF were 24.3%and 14.5%,*** adult males with AF,the prevalence was 11.7%and 8.7%,respectively,whereas in females it was 19.8%and 10.1%,*** older adults with AF,the prevalence rates of depression and anxiety were 40.3%and 33.6%,*** highest regional prevalence of depression and anxiety was observed in European(30.2%)and North American(19.8%)patients with *** In this study,we found that the prevalence of depression and anxiety among patients with AF varies with sex,region,and evaluation scales,suggesting the need for psychological interventions for patients with AF in clinical practice.

关键词： Atrial fibrillation Depression Anxiety Prevalence

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High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： Man Zhang Xiao-Xu Liu Tian-Yi Ji Yang Li Da-wei sheng Shao-Dong Li Pei-Pei Ren Ze-Xiang shen School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone(ZIF) and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber(CoP@CF) were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g^(-1) at 0.1 A·g^(-1)after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·g^(-1).The sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Freestanding anodes Sodium-ion batteries

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Influence of erosion voids and traffic loads on buried large-diameter reinforced concrete pipes

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Underground Space 2024年第4期17卷 120-131页

作者： Ming Xu Dawei shen Department of Civil Engineering Tsinghua UniversityBeijing 100084China Beijing Institute of Technology Beijing 100081China

Geotechnical centrifuge tests were conducted to examine the influence of invert voids and surface traffic loads on 1400 mm diameter reinforced concrete pipes buried with a shallow soil cover depth of 700 *** formation beneath the pipe was simulated during centrifuge *** test results revealed that before void formation,the surface load directly above the middle of the pipe caused a significant increase in not only the circumferential bending moments but also the longitudinal bending moments,the latter of which was considerable and could not be *** formation beneath the middle of the pipe led to a reduction in both the circumferential bending moments and longitudinal bending moments at all measuring positions,i.e.,crown,springline,and *** most significant reduction occurred at the invert,and there was even a reversal in the sign of the invert longitudinal bending moment.A comparison was made between centrifuge tests with erosion voids and surface loads at different horizontal positions,which had a marked influence even when the positions differed by half a pipe *** rotation played an important role in relieving large bending moments of pipe barrels in a jointed pipeline when the void and surface load were located at the joint.

关键词： Centrifuge test Erosion void Reinforced concrete pipe Traffic loading Longitudinal bending moment Joint rotation

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A full solid-state conceptual magnetocaloric refrigerator based on hybrid regeneration

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The Innovation 2024年第4期5卷 94-101,93页

作者： Yuan Lin Jing Wang wei Dai Kaiming Qiao Houbo Zhou Tongyun Zhao Fengxia Hu Baogen shen Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 101408China Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China

The environmental friendliness and high efficiency of magnetocaloric refrigeration make it a promising substitute for vapor compression ***,the common use of heat transfer fluid in conventional passive magnetic regenerators(PMRs)and active magnetic regenerators(AMRs)makes only partial materials contribute to the regeneration process,which produces large regeneration loss and greatly limits the regeneration effi-ciency and refrigeration performance at high ***,we propose a new conceptual hybrid magnetic regenerator(HMR)composed of multiple solid-state high thermal conductivity materials(HTCMs)and magnetocaloric materials(MCMs),in which both HTCM and MCM elements participate in the regeneration *** novel working mode could greatly reduce regeneration losses caused by dead volume,pressure losses,and temperature nonuniformity in heat transfer substances to markedly improve regeneration efficiency at high working *** the experimentally obtained adiabatic temperature change and magnetic work and with the help of finite element simulation,a maximum temperature of 26 K,a dramatically large cooling power of 8.3 kW/kg,and a maximum ideal exergy efficiency of 54.2%are achieved at the working frequency of 10 Hz for an ideal prototype device of a rotary HMR magnetocaloric refrigerator,which shows potential for achieving an integrative,advanced performance against current AMR/PMR systems.

关键词： solid state magnetic

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Design of bionic water jet thruster with double-chamber driven by electromagnetic force

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International Journal of Mechanical System Dynamics 2024年第3期4卷 292-302页

作者： Chong Cao Yasong Zhang Chengchun Zhang Chun shen Wen Cheng Zhenjiang wei Zhengyang Wu Luquan Ren Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchunChina weihai Junming Power Technology Co.Ltd. WeihaiChina

In response to the limitations of the single-chamber water jet thruster used in underwater vehicles mimicked by natural cephalopods,a novel approach involving a double-chamber water jet thruster has been *** thruster utilizes electromagnetic force to manipulate the diaphragm,thereby altering the volume of the upper and lower chambers to achieve water jet *** investigations were conducted to determine the tensile length-force characteristics of the diaphragm made of ***,key parameters of essential propulsion components,such as solenoid coils,electromagnets,and currents,were established based on the tensile length-force curve,and the propulsion capabilities of the system were evaluated through theoretical *** assessments indicate that the system does not produce reverse thrust regardless of whether the coil moves up or *** experimental results demonstrate that the maximum peak propulsion force generated by the dual-chamber water jet thruster within a 3-s cycle is 0.253N.

关键词： water jet thruster diaphragm electromagnetic force

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Allelopathic potentials of surrounding vegetation on seedling establishment of alpine cushion Arenaria polytrichoides

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Journal of Plant Ecology 2024年第2期17卷 146-160页

作者： Xu-Fang Chen Li-shen Qian hong-Hua Shi Ya-Zhou Zhang Min-Shu Song Hang Sun Jian-Guo Chen Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 101408China

When facilitating other species and sustaining plant community structures and biodiversity,alpine cushion plants simultaneously experience negative feedback effects from surrounding ***,the impact of surrounding vegetation on cushion dynamics remains poorly understood,particularly in terms of allelopathic *** investigate the allelopathic potentials of surrounding vegetation on seedling establishment of the typical cushion plant Arenaria polytrichoides *** an elevational gradient,we extracted potential allelopathic compounds and tested their impacts on seed germination and seedling growth of *** addition,exclusion experiments using activated carbon were conducted to further elucidate these *** results demonstrate that surrounding vegetation exhibits certain allelopathic potentials on *** seedling establishment,with variations observed based on elevation,source and concentration of allelopathy compounds,as well as growing ***,low-elevation vegetation exerts pronounced suppression on seedling ***,higher-elevation vegetation generally shows no effect on seed germination but stimulates seedling growth through allelopathy ***,aboveground vegetation predominantly inhibits both seed germination and seedling growth in low-elevation communities;however,the effects of belowground vegetation depend on elevation and extract concentration *** identifed allelopathic potentials of surrounding vegetation signifcantly infuence the population dynamics of cushion *** by potentially accelerating population degeneration in lower-elevation communities while ensuring consistent population recruitment and expansion in higher-elevation communities.

关键词： allelopathic potential community dynamic cushion plant seed germination seedling growth

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