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Quantum key distribution over a mimicked dynamic-scattering channel

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Science China(Information Sciences) 2024年第4期67卷 323-330页

作者： Qi-Hang LU fang-Xiang WANG Wei chen Hai-Yang fu Yin-Jie LU Shuang WANG De-Yong HE Zhen-Qiang YIN Guang-Can GUO Zheng-fu HAN CAS Key Laboratory of Quantum Information University of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China

Free-space quantum key distribution(QKD) plays an important role in the global quantum network. However, free space channels suffer from the atmospheric turbulence and scattering effects of haze,fog, and dust, which significantly weaken the performance of QKD or even block the secure quantum ***, we prove the performance of QKD over a dynamic scattering channel can be enhanced significantly using a fast wavefront shaping technique. The system achieves on average 10-dB enhancement of quantum transmission efficiency and establishes a secure quantum link for QKD. Our work demonstrates the feasibility of QKD through free-space dynamic scattering channels and enhances the deployment capability of complex-channel QKD system.

关键词： quantum key distribution free space channel channel turbulence channel scattering wavefront shaping

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

Observing eddy dye patches induced by shear instabilities in the surf zone on a plane beach

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Acta Oceanologica Sinica 2024年第3期43卷 15-29页

作者： Chunping Ren Nannan fu Chong Yu Yuchuan Bai Kezhao fang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China College of Water Resource Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The effects of surf zone eddy generated by alongshore currents on the deformation and transport of dye are still poorly understood,and related tracer release experiments are ***,a tracer release laboratory experiment was conducted under monochromatic,unidirectional incident waves with a large incident angle(30°)on a plane beach with a 1:100 slope in a large wave basin.A charge-coupled device suspended above the basin recorded the dye patch *** evolution of eddy dye patch was observed and the transport and diffusion were analyzed based on the collected ***,a linear instability numerical model was adopted to calculate the perturbation velocity field at the initial *** observation and image processing results show that surf zone eddy patches occurred and were separated from the original dye *** numerical analysis results demonstrate that the structure of the perturbation velocity field is consistent with the experimental observations,and that the ejection of eddy patches shoreward or offshore may be ascribed to the double vortex.

关键词： surf zone tracer release experiment evolution of eddy patch shear instability of alongshore currents

Relationship between structure and microwave dielectric properties of Li_(3)Mg_(4)Nb_(1-x)Ta_(x)O_(8)ceramics

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Journal of Materiomics 2024年第1期10卷 245-252页

作者： Chongsheng Wu Kui Liu Honglan Lai fang xu School of Mechanical and Electrical Engineering Chengdu University of TechnologyChengduSichuan610059China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China State Key Laboratory of Environment-friendly Energy Materials Southwest University of Science and TechnologyMianyang621010China

Herein,the sintering behavior and dielectric properties of Ta5+-doped Li3Mg4NbO8 ceramics were investigated by solid-phase reactions in combination with first-principles *** particular,Li_(3)Mg_(4)Nb_(0.96)Ta_(0.04)O_(8)illustrates the best dielectric properties after sintering at 1,175℃withεr=13.71±0.20,Q×f=(132,112±2,391)GHz(increased by 25%)andτf=(25.07±1.36)×10^(−6)℃^(−1).The non-intrinsic factors reflect that a small amount of Ta^(5+)doping produces a secondary phase,increased densification,and grain size,all of which optimize the dielectric *** dominant intrinsic factors indicate that the increase in bond ionicity,the greater polarization of Ta^(5+),and the blueshift of the Raman characteristic peak all lead to an increase inε*** increase in lattice energy and the decrease in the damping behavior of the Nb/Ta-O bond vibrations lead to an increase in Q×*** weakening of the Nb/TaO_(6) octahedral distortion leads to an optimization ofτ*** modified Li_(3)Mg_(4)Nb_(0.96)Ta_(0.04)O_(8) ceramics have promising applications in microwave communications.

关键词： First-principles Li_(3)Mg_(4)NbO_(8),dielectric properties Lattice vibration

Strong electron correlation-induced Mott-insulating electrides of Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)

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Matter and Radiation at Extremes 2024年第3期9卷 74-82页

作者： Ya xu Lu Zheng Yunkun Zhang Zhuangfei Zhang QianQian Wang Yuewen Zhang Liangchao chen Chao fang Biao Wan Huiyang Gou Key Laboratory of Material Physics of Ministry of Education School of Physics and Laboratory of Zhongyuan LightZhengzhou UniversityZhengzhou 450052China School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan 056038China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

The presence of interstitial electrons in electrides endows them with interesting attributes,such as low work function,high carrier concentration,and unique magnetic *** knowledge and understanding of electrides are thus of both scientific and technological ***,we employ first-principles calculations to investigate Mott-insulating Ae_(5)X_(3)(Ae=Ca,Sr,and Ba;X=As and Sb)electrides with Mn_(5)Si_(3)-type structure,in which half-filled interstitial electrons serve as ions and are *** Mott-insulating property is induced by strong electron correlation between the nearest interstitial electrons,resulting in spin splitting and a separation between occupied and unoccupied *** half-filled antiferromagnetic configuration and localization of the interstitial electrons are critical for the Mott-insulating properties of these *** with that in intermetallic electrides,the orbital hybridization between the half-filled interstitial electrons and the surrounding atoms is weak,leading to highly localized magnetic centers and pronounced correlation ***,the Mott-insulating electrides Ae_(5)X_(3)have very large indirect bandgaps(0.30 eV).In addition,high pressure is found to strengthen the strong correlation effects and enlarge the *** present results provide a deeper understanding of the formation mechanism of Mott-insulating electrides and provide guidance for the search for new strongly correlated electrides.

关键词： intermetallic filled occupied

Building stabilized Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode enables an outstanding room‐/low‐temperature aqueous Zn‐ion batteries

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Carbon Energy 2024年第8期6卷 25-35页

作者： Ao Wang Dai‐Huo Liu Lin Yang fang xu Dan Luo Haozhen Dou Mengqin Song Chunyan xu Beinuo Zhang Jialin Zheng Zhongwei chen Zhengyu Bai Key Laboratory of Green Chemical Media and Reactions Ministry of EducationCollaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenanChina The State Key Laboratory of Catalysis(SKLC) Power Battery and System Research CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina

Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+)storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion *** this work,a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium *** pre‐intercalated Cu ions act as pillars to pin the vanadium oxide(V‐O)layers,establishing stabilized two‐dimensional channels for fast Zn^(2+)*** occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects(Od),which boosts the Zn^(2+)diffusion *** a result,as‐prepared Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode shows outstanding Zn‐storage capabilities under room‐and lowtemperature environments(e.g.,440.3 mAh g^(−1)at room temperature and 294.3 mAh g^(−1)at−60°C).Importantly,it shows a long cycling life and high capacity retention of 93.4%over 2500 cycles at 2 A g^(−1)at−60°***,the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman *** strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/lowtemperature vanadium‐based cathode materials.

关键词： aqueous zinc‐ion batteries Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O oxygen defects room‐/lowtemperature performance stabilized nanostructure

A Methodology for Assessing Axial Compressor Stability with Inlet Temperature Ramp Distortion

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Journal of Thermal Science 2024年第3期33卷 856-871页

作者： SUN Dakun GU Benhao NING fangfei fang Yibo DONG xu xu Dengke SUN Xiaofeng School of Energy and Power Engineering Beihang UniversityBeijing102206China Research Institute of Aero-engine Beihang UniversityBeijing102206China

Based on a small perturbation stability model for periodic flow,the effects of inlet total temperature ramp distortion on the axial compressor are investigated and the compressor stability is quantitatively *** the beginning,a small perturbation stability model for the periodic flow in compressors is proposed,referring to the governing equations of the Harmonic Balance *** stability model is validated on a single-stage low-speed compressor TA36 with uniform inlet ***,the unsteady flow of TA36 with different inlet total temperature ramps and constant back pressure is simulated based on the Harmonic Balance *** on these simulations,the compressor stability is analyzed using the proposed small perturbation ***,the Dynamic Mode Decomposition method is employed to accurately extract pressure *** two parameters of the temperature ramp,ramp rate and Strouhal number,are discussed in this *** results indicate the occurrence and extension of hysteresis loops in the rows,and a decrease in compressor stability with increasing ramp *** performance is divided into two phases,stable and limit,based on the ramp ***,the model predictions suggest that a decrease in period length and an increase in Strouhal number lead to improved compressor *** DMD results imply that for compressors with inlet temperature ramp distortion,the increase of high-order modes and oscillations at the rotor tip is always the signal of decreasing stability.

关键词： axial compressor stability small perturbation model inlet temperature ramp distortion harmonic balance method dynamic mode decomposition method

Prediction of suitable water content in granulation of sintering mixture based on Litster's model

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Journal of Iron and Steel Research International 2024年第3期31卷 552-560页

作者： fang-lei Dai Xiao-hui Fan Xiao-xian Huang xu-ling chen Min Gan Zhi-yun Ji Zeng-qing Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Suitable water content plays a decisive role in the granulation of sintering ***,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation *** granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were *** results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water *** an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation ***,as the amount of concentrates increased,the suitable water content first increased and then remained *** influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.

关键词： Adhesive particle Sintering mixture Granulation effectiveness Suitable water content

A Dietary Source of High Level of Fluoroquinolone Tolerance in mcr-Carrying Gram-Negative Bacteria

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Research 2024年第3期2023卷 105-121页

作者： Tianqi xu Dan fang fulei Li Zhiqiang Wang Yuan Liu Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses College of Veterinary MedicineYangzhou UniversityYangzhou 225009China. Joint International Research Laboratory of Agriculture and Agri-Product Safety the Ministry of Education of ChinaYangzhou UniversityYangzhou 225009China. Institute of Comparative Medicine Yangzhou UniversityYangzhou 225009China.

The emergence of antibiotic tolerance,characterized by the prolonged survival of bacteria following antibiotic exposure,in natural bacterial populations,especially in pathogens carrying antibiotic resistance genes,has been an increasing threat to public ***,the major causes contributing to the formation of antibiotic tolerance and underlying molecular mechanisms are yet poorly ***,we show that potassium sorbate(PS),a widely used food additive,triggers a high level of fluoroquinolone tolerance in bacteria carrying mobile colistin resistance gene *** studies demonstrate that PS treatment results in the accumulation of intracellular fumarate,which activates bacterial two-component system and decreases the expression level of outer membrane protein OmpF,thereby reducing the uptake of *** addition,the supplementation of PS inhibits aerobic respiration,reduces reactive oxygen species production and alleviates DNA damage caused by bactericidal ***,we demonstrate that succinate,an intermediate product of the tricarboxylic acid cycle,overcomes PS-mediated ciprofloxacin *** multiple animal models,ciprofloxacin treatment displays failure outcomes in PS preadministrated animals,including comparable survival and bacterial loads with the vehicle *** together,our works offer novel mechanistic insights into the development of antibiotic tolerance and uncover potential risks associated with PS use.

关键词： overcome thereby additive