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Photoionisation detection of a single Er3+ ion with sub-100-ns time resolution

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National Science Review 2024年第4期11卷 38-45页

作者： Yangbo zhang wenda Fan Jiliang Yang Hao Guan Qi zhang Xi Qin changkui Duan Gabriele G.de Boo Brett c.Johnson Jeffrey c.Mc callum Matthew J.Sellars Sven Rogge chunming Yin Jiangfeng Du cAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences 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 centre of Excellence for Quantum computation and communication Technology School of Physics University of New South Wales centre of Excellence for Quantum computation and communication Technology School of Engineering RMIT University centre of Excellence for Quantum computation and communication Technology School of Physics University of Melbourne centre of Excellence for Quantum computation and communication Technology Research School of Physics and Engineering Australian National University

Efficient detection of single optical centres in solids is essential for quantum information processing, sensing and single-photon generation *** this work,we use radio-frequency（RF） reflectometry to electrically detect the photoionisation induced by a single Er3+ion in *** high bandwidth and sensitivity of the RF reflectometry provide sub-100-ns time resolution for the photoionisation *** this technique,the optically excited state lifetime of a single Er3+ion in a Si nano-transistor is measured for the first time to be 0.49±0.04μ*** results demonstrate an efficient approach for detecting a charge state change induced by Er excitation and *** approach could be used for fast readout of other single optical centres in solids and is attractive for large-scale integrated optical quantum systems thanks to the multi-channel RF reflectometry demonstrated with frequency multiplexing techniques.

关键词： single optical centres erbium ions RF reflectometry photoionisation detection

Distinct Electrical and Mechanical Responses of a cu-10Fe composite Prepared by Hot-Pressed Sintering and Post Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.Y.Yue S.Y.Peng X.zhang c.N.He Y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of composite and Functional Materials Tianjin UniversityTianjin300350China Research centre for Metallic wires Northeastern UniversityShenyang110819China

A cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the cu-10wt%Fe *** cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IAcS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance cu-based in-situ composites by post treatment.

关键词： cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Microstructure evolution and strengthening mechanism of high -performance powder metallurgy TA15 titanium alloy by hot rolling

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1426-1436页

作者： Ying Gao ce zhang Jiazhen zhang Xin Lu Beijing Advanced Innovation center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsInstitute for Advanced Ma-terials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Engineering Research center for Advanced Rolling Technology National Engineering Research Center for Flat Rolling EquipmentInstitute of Engin-eering TechnologyUniversity of Science and Technology BeijingBeijing 100083China

Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying *** this study,Ti–6.5Al–2Zr–Mo–V(TA15)titanium alloy plates were prepared by cold press-ing sintering combined with high-temperature hot *** microstructure and mechanical properties under different process paramet-ers were *** microscope,electron backscatter diffraction,and others were applied to characterize the microstructure evolution and mechanical properties strengthening *** results showed that the chemical compositions were uniformly dif-fused without segregation during sintering,and the closing of the matrix craters was accelerated by increasing the sintering *** block was hot rolled at 1200℃ with an 80%reduction under only two passes without *** strength and elongation of the plate at 20–25℃ after solution and aging were 1247 MPa and 14.0%,respectively,which were increased by 24.5%and 40.0%,respect-ively,compared with the as-sintered alloy at 1300℃.The microstructure was significantly refined by continuous dynamic recrystalliza-tion,which was completed by the rotation and dislocation absorption of the substructure surrounded by low-angle grain *** hot rolling combined with heat treatment,the strength and plasticity of PM-TA15 were significantly improved,which resulted from the dense,uniform,and fine recrystallization structure and the synergistic effect of multiple slip systems.

关键词： elemental powder powder metallurgy titanium alloy hot rolling strength and plasticity

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Reliable Data collection Model and Transmission Framework in Large-Scale wireless Medical Sensor Networks

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computer Modeling in Engineering & Sciences 2024年第7期140卷 1077-1102页

作者： Haosong Gou Gaoyi zhang RenêRipardo calixto Senthil Kumar Jagatheesaperumal Victor Hugo c.de Albuquerque china Mobile Group Sichuan co. Ltd.Chengdu640041China Department of Teleinformatics Engineering Federal University of CearáFortaleza60455-970Brazil Department of Electronics&communication Engineering Mepco Schlenk Engineering CollegeSivakasi626005India

Large-scale wireless sensor networks(wSNs)play a critical role in monitoring dangerous scenarios and responding to medical ***,the inherent instability and error-prone nature of wireless links present significant challenges,necessitating efficient data collection and reliable transmission *** paper addresses the limitations of existing data transmission and recovery protocols by proposing a systematic end-to-end design tailored for medical event-driven cluster-based large-scale *** primary goal is to enhance the reliability of data collection and transmission services,ensuring a comprehensive and practical *** approach focuses on refining the hop-count-based routing scheme to achieve fairness in forwarding ***,it emphasizes reliable data collection within clusters and establishes robust data transmission over multiple *** systematic improvements are designed to optimize the overall performance of the wSN in real-world *** results of the proposed protocol validate its exceptional performance compared to other prominent data transmission *** evaluation spans varying sensor densities,wireless channel conditions,and packet transmission rates,showcasing the protocol’s superiority in ensuring reliable and efficient data *** systematic end-to-end design successfully addresses the challenges posed by the instability of wireless links in *** prioritizing fairness,reliability,and efficiency,the proposed protocol demonstrates its efficacy in enhancing data collection and transmission services,thereby offering a valuable contribution to the field of medical event-drivenwSNs.

关键词： wireless sensor networks reliable data transmission medical emergencies cluster data collection routing scheme

Effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens

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Eye and Vision 2024年第3期10卷 31-40页

作者： Lingling Niu Zhe zhang Huamao Miao Jing Zhao Xiaoying wang Ji c.He Xingtao Zhou Department of Ophthalmology and Optometry Eye&ENT HospitalFudan UniversityShanghaiChina NHc Key Laboratory of Myopia(Fudan University) ShanghaiChina Key Laboratory of Myopia Chinese Academy of Medical SciencesShanghaiChina Shanghai Research center of Ophthalmology and Optometry ShanghaiChina New England college of Optometry MABostonUSA

Background To investigate the effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens(IcL V4c).Methods This observational study recruited 62 eyes of 31 myopia patients underwent IcL V4c *** segment optical coherence tomography(AS-OcT)assessed the anterior chamber depth(AcD),AcD-IcL(distance from the corneal endothelium to anterior surface of the IcL V4c),vault(distance between the posterior IcL V4c surface and anterior crystalline lens surface),and crystalline lens tilt under various lighting conditions and accommodation relative to the corneal topographic axis at one year after IcL V4c *** was defined as the scotopic condition,which was also the non-accommodative stimulus *** IcL V4c tilt was analyzed using *** significance level was set at PcD-IcL values were similar under various lighting conditions(P=0.978)but decreased during accommodation(Pwas significantly smaller under mesopic and photopic conditions than the baseline(P=0.044 and Pctively)but remained unchanged during accommodation(P=0.058).The inferotemporal proportion of IcL V4c(88.7%,55 eyes)and crystalline lens(74.2%,46 eyes)tilts were not significantly different(P=0.063).crystalline lens under various lighting conditions and accommodation exhibited similar *** vertical tilt of IcL V4c was significantly larger under photopic conditions than the baseline(P=0.038).The horizontal and total tilts were significantly decreased during accommodation(P=0.043 and 0.013,respectively).conclusions The axial position of IcL V4c in the anterior chamber was stable under various lighting *** conditions and accommodation may influence vertical,horizontal and total tilts of IcL V4c.

关键词： Implantable collamer lens Anterior segment optical coherence tomography Myopia Tilt

Dynamic Modeling and Experimental Verification of an RPR Type compliant Paralle Mechanism with Low Orders

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chinese Journal of Mechanical Engineering 2024年第3期37卷 83-94页

作者： Shuang zhang Jingfang Liu Huafeng Ding Yanbin zhang School of Mechatronics Engineering Henan University of Science and TechnologyLuoyangHenanChina Faculty of Materials and Manufacturing College of Mechanical Engineering and Applied Electronics TechnologyBeijing University of TechnologyBeijingChina Key laboratory of advanced manufacturing technology Beijing University of TechnologyBeijingChina School of Mechanical Engineering and Electronic Information China University of Geosciences(Wuhan)WuhanChina center of Machinery Equipment Advanced Manufacturing of Henan Province LuoyangChina

Efficiency of calculating a dynamic response is an important point of the compliant mechanism for posture *** modeling with low orders of a 2R1T compliant parallel mechanism is studied in the *** mechanism with two out-of-plane rotational and one lifting degrees of freedom(DoFs)plays an important role in posture *** on elastic beam theory,the stiffness matrix and mass matrix of the beam element are established where the moment of inertia is *** improve solving efficiency,a dynamic model with low orders of the mechanism is established based on a modified modal synthesis ***,each branch of the RPR type mechanism is divided into a ***,a set of hypothetical modes of each substructure is obtained based on the c-B ***,dynamic equation of the whole mechanism is established by the substructure assembly.A dynamic experiment is conducted to verify the dynamic characteristics of the compliant mechanism.

关键词： compliant parallel mechanism Dynamic model Modal synthesis method Dynamic experiment

cF-DAN: Facial-expression recognition based on cross-fusion dual-attention network

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computational Visual Media 2024年第3期10卷 593-608页

作者： Fan zhang Gongguan chen Hua wang caiming zhang Shandong Technology and Business University Shandong 264005China School of Information and Electrical Engineering Ludong UniversityYantai 264025China Shangdong University Shandong 250100China

Recently, facial-expression recognition (FER)has primarily focused on images in the wild, includingfactors such as face occlusion and image blurring, ratherthan laboratory images. complex ﬁeld environmentshave introduced new challenges to FER. To addressthese challenges, this study proposes a cross-fusion dualattention network. The network comprises three parts:(1) a cross-fusion grouped dual-attention mechanism toreﬁne local features and obtain global information;(2) aproposed c2 activation function construction method,which is a piecewise cubic polynomial with threedegrees of freedom, requiring less computation withimproved ﬂexibility and recognition abilities, whichcan better address slow running speeds and neuroninactivation problems;and (3) a closed-loop operationbetween the self-attention distillation process andresidual connections to suppress redundant informationand improve the generalization ability of the *** recognition accuracies on the RAF-DB, FERPlus,and AffectNet datasets were 92.78%, 92.02%, and63.58%, respectively. Experiments show that this modelcan provide more effective solutions for FER tasks.

关键词： facial-expression recognition(FER) cubic polynomial activation function dualattention mechanism interactive learning self-attention distillation

Using Natural Radionuclides to Trace Sources of Suspended Particles in the Lower Reaches of the Yellow River

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Journal of Ocean University of china 2024年第1期23卷 99-108页

作者： zhang Han BURNETT cwilliam zhang Xiaojie ZHAO Shibin YANG Disong NAN Haiming YU Zhigang XU Bochao Frontiers Science center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China college of chemistry and chemical Engineering Ocean University of ChinaQingdao 266100China Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahasseeFL 32306USA North china Sea Environmental Monitoring center State Oceanic AdministrationKey Laboratory of Ecological Prewarning and Protection of Bohai SeaMNRQingdao 266033China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266033China

Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and *** analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic Station(Huanghe or Yellow River)every month over a one-year *** showed that medium silt(16–32µm)was the main *** expected,the activity of each radionuclide decreased with an increase of particle *** examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different *** results indicate that fine SPM(was mainly from the erosion of soil along the lower reaches of the Yellow River,while coarse SPM(>32µm)was mainly derived from resuspension of riverbed *** high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream *** occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea.

关键词： the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator

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Facilitating prelithiation of silicon carbon anode by localized high-concentration electrolyte for high-rate and long-cycle lithium storage

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carbon Energy 2024年第6期6卷 216-233页

作者： Yuanxing zhang Borong wu Jiaying Bi Xinyu zhang Daobin Mu Xin-Yu zhang Ling zhang Yao Xiao Feng wu School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina chongqing Innovation center Beijing Institute of TechnologyChongqingChina college of New Energy Xi′an Shiyou UniversityXi′anChina Institute for carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhouChina Key Laboratory of Advanced Energy Materials chemistry(Ministry of Education) Nankai UniversityTianjinChina

The commercialization of silicon-based anodes is affected by their low initial coulombic efficiency(IcE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)***,a feasible and cost-effective prelithiation method under a localized highconcentration electrolyte system(LHcE)for the silicon-silica/graphite(Si-SiO_(2)/c@G)anode is designed for stabilizing the SEI layer and enhancing the *** thin SiO_(2)/c layers with-NH2 groups covered on nano-Si surfaces are demonstrated to be beneficial to the prelithiation process by density functional theory calculations and electrochemical *** SEI formed under LHcE is proven to be rich in ionic conductivity,inorganic substances,and flexible organic ***,faster Li+transportation across the SEI further enhances the prelithiation effect and the rate performance of Si-SiO_(2)/c@G *** also leads to uniform decomposition and high stability of the SEI with abundant organic *** a result,the prepared anode shows a high reversible specific capacity of 937.5 mAh g^(-1)after 400 cycles at a current density of 1 *** 811‖Li-SSGLHcE full cell achieves a high-capacity retention of 126.15 mAh g^(-1)at 1 c over 750 cycles with 84.82%IcE,indicating the great value of this strategy for Si-based anodes in large-scale applications.

关键词： localized high-concentration electrolytes prelithiation SEI layer silicon anode