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Design and fabrication of button-style beam position monitors for the HEPS synchrotron light facility

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Nuclear Science and Techniques 2022年第11期33卷 61-78页

作者： Jun He Yan-Feng Sui Yong Li Xu-Hui Tang Lin Wang Fang Liu Zhi Liu Ling-Da Yu Xiao-Yu Liu Tao-Guang Xu jian-she cao Jun-Hui Yue Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

At the High Energy Photon Source (HEPS),a high orbital stability of typically 10% of the beam size and angular divergence must be *** beam size at the insertion devices is 10μm horizontally and 1μm vertically,which implies that the beam orbit must be stabilized to the sub-micrometer *** results in stringent tolerance and quality control requirements for the series production of beam position monitor (BPM) *** this study,analytical formulas were used and CST simulations were performed to analyze the effects of the mechanical tolerances of BPM pickups on beam position *** results of electromagnetic?eld simulations revealed how various mechanical errors,such as button size and location accuracy,as well as the related button capacitance,exert different in?uences on the beam position *** performance of an actual BPM pickup was measured,along with an assessment of the error on the beam position ***,a wake?eld analysis,including an investigation of trapped resonant modes and related thermal deformation,was conducted.

关键词： High energy photon source BPM Error CST Tolerances

维普期刊数据库

A high sensitivity tune measurement system for BEPCII

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Radiation Detection Technology and Methods 2022年第1期6卷 88-96页

作者： Jun He Yan-feng Sui Yan-hua Lu Yao-yao Du Lin Wang Hui-zhou Ma Yong Li Ying Zhao Ling-da Yu Tao-guang Xu Jun-hui Yue jian-she cao Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

Background The tune is one of the most important parameters of the storage ring which play a crucial role in the brightness *** synchrotron radiation will suppress the oscillation and make the detection unusual difficulty without any kicker *** A new high sensitivity tune measurement system is developed to show the real-time tune during the *** Peak diode detectors are used to convert short beam pulses from a button BPM into slowly varying *** DC components,constituting a large background related to beam offsets,are suppressed by series capacitors,while the small signals related to beam oscillations are passed to the subsequent stages for amplification and *** A direct diode detection technique based on the diode peak hold circuit could increase the sensitivity by hundreds time which gets a clearly tune peak even with synchrotron radiation and bunch-by-bunch feedback damping.

关键词： Collider High sensitivity Direct diode detection Real-time tune Red Pitaya

Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： jian cao Yong-jiang GUO Kai-ming YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation *** convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal *** is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in *** the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive *** LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the *** external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation

维普期刊数据库

Fabrication of a novel electrochemical sensor based on MnFe_(2)O_(4)/graphene modified glassy carbon electrode for the sensitive detection of bisphenol A

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Journal of Central South University 2024年第6期31卷 1856-1869页

作者： GAO Si-lei TANG jian-she XIANG Li LONG Jin-wei Department of Environmental and Energy Engineering Anhui Jianzhu UniversityHefei 230601China Anhui Provincial Key Laboratory of Environmental Pollution Control and Resource Reuse Hefei 230601China

Manganese ferrite(MnFe_(2)O_(4))has the advantages of simple preparation,high resistivity,and high crystal ***,we have developed an electrochemical sensor utilizing graphene and MnFe_(2)O_(4) nanocomposites modified glassy carbon electrode(GCE),which is very efficient and sensitive to detect bisphenol A(BPA).MnFe_(2)O_(4)/graphene(GR)was synthesized by immobilizing the MnFe_(2)O_(4) microspheres on the graphene nanosheets via a simple one-pot solvothermal *** morphology and structure of the MnFe_(2)O_(4)/GR nanocomposite have been characterized through scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).In addition,electrochemical properties of the modified materials are comparably explored by means of cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS)and differential pulse voltammetry(DPV).Under the optimal conditions,the proposed electrochemical sensor for the detection of BPA has a linear range of 0.8-400μmol/L and a detection limit of 0.0235μmol/L(S/N=3)with high sensitivity,good selectivity and high *** addition,the proposed sensor was used to measure the content of BPA in real water samples with a recovery rate of 97.94%-104.56%.At present,the synthesis of MnFe_(2)O_(4)/GR provides more opportunities for the electrochemical detection of BPA in practical applications.

关键词： MnFe_(2)O_(4) graphene electrochemical sensor bisphenol A

Numerical Simulation of Wet Particles Motion in a Vertical Powder Dryer

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Fluid Dynamics & Materials Processing 2024年第8期20卷 1823-1846页

作者： Long Yu Dongdong Pang Minmin she Hongwei Qiu Ping cao Xiongwei You School of Petrochemical Engineering Lanzhou University of TechnologyLanzhou730050China

In this study,the motion of wet particles in the drying unit of a vertical powder dryer is investigated by using a Discrete element method(DEM)coupled with a liquid bridge *** particular,by varying parameters such as the particle mass flow rates,the superficial gas velocities,and superficial gas temperatures,the influence of the moisture content on the flow behavior is *** results show that when the moisture content increases,the mean particle velocity decreases while the bed mean solid“holdup”and the mean residence time(MRT)of particles *** is also found that the local solid holdup is relatively higher in the near-wall region and decreases towards the near-fluid *** regression models are introduced accordingly for the mean particle velocity and the bed mean solid holdup by means of the RSM-BBD(Response surface methodology-Box-Behnken design)method to obtain the optimal combination of parameters for flooding ***,the optimal results are compared with numerical *** the relative error is less than 10%,this demonstrates that the proposed methodology can accurately describe the particle flow dynamics in the drying unit.

关键词： Counter-current gas-solid flow moisture content flow characteristics RSM-BBD

Two-layer Lagrange-based relay network topology and trajectory design for solar system explorations

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Science China(Information Sciences) 2024年第6期67卷 342-358页

作者： Jun cao jian JIAO Hao LIU Rongxing LU Qinyu ZHANG Guangdong Provincial Key Laboratory of Aerospace Communication and Networking Technology Harbin Institute of Technology (Shenzhen) Faculty of Computer Science (FCS) University of New Brunswick

Exploration targeting outer planets and even the edge of the solar system is an emerging direction for the deep-space exploration in the next decades. To address this challenge, a novel two-layer Lagrangebased relay network topology is proposed in this study. Specifically, we utilize the Sun-Mars and Sun-Saturn Lagrange points(LPs) L4 and L5 to build a two-layer backbone relay network, which ensures continuous and high-efficiency communication capability for the exploration of the solar system. Furthermore, we utilize the planetary gravity assist and design the transfer trajectory of backbone relays with the help of planetary celestial body motion equations and Kepler's laws. Moreover, we conduct link budget analysis for multihop relay transmission under Gamma-Gamma distribution, shadowed Rician fading, and additive white Gaussian noise channels in several typical exploration scenarios and validate that the LP relays can effectively support future deep-space exploration missions.

关键词： deep-space communication Lagrangian points backbone relay network transfer trajectory relay selection

同方期刊数据库

Leader-follower Optimal Selection Method for Distributed Control System in Active Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 314-323页

作者： jian Le Liangang Zhao cao Wang Qian Zhou Yang Wang School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China

Aiming at the shortcomings of a traditional centralized control in an active distribution network(AND),this paper proposes a leader-follower distributed group cooperative control strategy to realize multiple operation and control tasks for an *** distributed information exchange protocols of the distributed generation(DG)group devoted to node voltage regulation or exchange power control are developed using a DG power utilization ratio as the consensus *** these bases,this study further investigates the leader optimal selection method for a DG group to improve the response speed of the distributed control ***,a single or multiple leader selection model is established to minimize the constraints of the one-step convergence factor and the number of leaders to improve the response speed of the distributed control *** simulation results of the IEEE 33 bus standard test system show the effectiveness of the proposed distributed control *** addition,the response speed of a DG control group can be improved effectively when the single or multiple leaders are selected optimally.

关键词： Active distribution1network consensus algorithm leader-follower system mixed-integer semidefinite programming optimal distributed control

Difference in microstructural characteristics of stamp-charged coke and gravity-charged coke with approximate macroscopic performance

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1050-1062页

作者： Chong Zou Zheng-yan Huang jian-yun Li Bin Li Shi-wei Liu Yuan she School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710311ShaanxiChina Technical Center of Shandong Iron and Steel Co. Ltd.(Laiwu Branch)Jinan271104ShandongChina

The microstructural characteristics including optical texture,porosity and pore structure and chemical structure of stamp-charged coke(SCC)and gravity-charged coke(GCC)with similar conventional macro-indicators were investigated,and the properties including micro-strength,reactivity of coke matrix and that after alkali enrichment were comparatively studied by various characterization *** anisotropic structure of SCC is composed of high content of fine mosaic texture,while the content of medium mosaic texture,coarse texture and fibrous texture is *** statistical average shows that the fine mosaic average of SCC(24.89%)is 3.78 times the GCC average(6.58%),and the coarse mosaic average(1.24%)is only about 1/3 of the GCC average(3.43%).The porosity of SCC is lower than that of GCC,but tamping process does not lead to the fact that the number of closed pores of SCC is significantly lower than that of *** the structure of SCC is compact,its pore number is large and the pore wall is *** of coke with diameter less than 150 nm seem unaffected by tamping *** aromatic structure of SCC was less ordered than that of GCC,which was speculated to be related to the addition of more low metamorphic coal in *** microscopic strength and structural strength of SCC are lower than those of *** reactivity of coke matrix is affected by the specific surface area,but it is not the determining factor of its *** improvement in dissolution reactivity of coke after potassium enrichment is independent of coke type.

关键词： Stamp-charged coke Optical texture Porosity Microstructure Reactivity

Non-ionizing radiation-induced cellular senescence and age-related diseases

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Radiation Medicine and Protection 2024年第2期5卷 118-123页

作者： Haiying Wang jian Tong Yi cao School of Public Health Suzhou Medical College of Soochow UniversitySuzhou 215123China

Cellular senescence has emerged as an important contributor to aging and age-related ***-ionizing radiation(NIR),including ultraviolet radiation and electromagnetic fields,has been increasingly recognized as a key inducer of premature *** this review,we discuss the molecular mechanisms of NIR-induced cellular senescence and its effects on aging and age-related *** also summarize the modulation strategies for NIR-induced cellular senescence.A better understanding of the complex relationship between nonionizing radiation,cellular senescence and age-related pathology may lead to interventions to ameliorate radiation damage and delay *** research is still needed to elucidate the precise mechanisms,dose-response effects,and to develop protective strategies against radiation-induced senescence.

关键词： Non-ionizing radiation Cellular senescence Aging Age-related diseases DNA damage Oxidative stress Intervention strategies