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Preliminary study on detection and cleaning of parasitic bunches

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Nuclear Science and Techniques 2021年第10期32卷 1-11页

作者： jun He Yan-Feng Sui Yan-Hua Lu Di Yin Zhe Duan Sai-Ke Tian De-Chong Zhu Ying Zhao jun-hui yue Jian-She Cao Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

To establish a nuclear resonant scattering beamline at the High Energy Photon Source(HEPS),it is essential to develop tools for detection and cleaning of parasitic bunches,for meeting the stringent demands on bunch *** this end,a novel time-correlated single-photon counting system was implemented at the electron storage ring of the Beijing Electron–Positron Collider II(BEPCII).The purity deterioration process over a week-long operation was recorded by the *** this study,the mechanism of impurity growth was analyzed by numerical methods and validated on *** agreement between the experimental results and the cal-culation was fairly *** main sources of parasitic bunches,pre-accelerators and the Touschek scattering were confirmed.A bunch-cleaning technique,based on a sinu-soidal signal mixed with a pseudo-square wave,was also developed and implemented,and its capability to improve the bunch purity to the level of 10–7 was experimentally *** present the experimental setup,princi-ple,and measurement results of a system for detection and cleaning of parasitic bunches.

关键词： Parasitic bunches Impurity growth High energy photon source(HEPS)

Highly Red Emissive Conjugated Homopolymers Based on Double B←N Bridged Bipyridine Unit

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Chinese Journal of Polymer Science 2024年第8期42卷 1029-1037页

作者： Yu-yue Gao Kai-Yuan Zhang Shu-Meng Wang hui Tong jun Liu State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Conjugated homopolymers based on six-member rings,e.g.,polyfluorene,always exhibit blue emission and conjugated homopolymers based on five-member rings,e.g.,polythiophene,can give red emission with low *** this work,we report a series of new conjugated homopolymers based on six-member rings with high-efficiency deep-red *** repeating units of the red light emitting homopolymers are double B←N bridged bipyridine(BNBP)with the boron atoms functionalized with diphenyl,borafluorene,and 2,7-di-tert-butyl-borafluorene groups,*** relationship between the chemical structures and the opto-electronic properties of the monomers and the homopolymers has been systematically *** three polymers emit pure red light(λ_(max)=656 nm)or deep red light(λ_(max)=693 nm)with fluorescence quantum efficiency in solution higher than 60%.The polymers can be used as the emitters in solution-processed organic light-emitting diodes with red emission and decent device *** work indicates a new strategy to design highly efficient light emitting conjugated polymers.

关键词： Conjugated homopolymers Double B←N bridged bipyridine(BNBP) Deep-red emission High fluorescent efficiency

Lath-like phases formed at an extremely high temperature in a Mg-RE(RE=rare earth)-Al alloy

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Rare Metals 2024年第8期43卷 3937-3945页

作者： Bo Deng Shu-hui Lv Qiang Yang Dong-yue Zhao jun-Yuan Fan Xin Qiu School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Chongqing Research Institute Changchun University of Science and TechnologyChongqing 401135China

Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)*** this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at 873 ***-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM) characterizations indicate that most of them are Mg-containing Al_(2)(Gd,Sm),with the atomic ratio of Mg:Al:(Gd,Sm) being ~1:1:1;a small part of them with relatively wider thickness are long-period stacking ordered(LPSO) phases simultaneously containing both 14H and 18R *** followed common orientation relationships with Mg matrix as those reported in previous *** addition,many Mg laths were observed in the primary blocky Al_(2)(Gd,Sm) phase at grain boundaries,where the atomic ratio of Al:(Gd,Sm) in the Al_(2)(Gd,Sm) matrix was 2:***,density functional theory(DFT) calculations illustrated the detail structure of the re-constructed Mg/Al_(2)RE interface and simultaneously deduced the underlying reason for the re-dissolution of the newly formed Mg-containing Al_(2)(Gd,Sm) plates in α-Mg matrix.

关键词： Magnesium alloy HAADF-STEM Microstructures Intermetallic particles Orientation relationships Interfaces

Sora for foundation robots with parallel intelligence:three world models,three robotic systems

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Frontiers of Information Technology & Electronic Engineering 2024年第7期25卷 917-923页

作者： Lili FAN Chao GUO Yonglin TIAN hui ZHANG jun ZHANG Fei-yue WANG School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China School of Electrical Engineering Wuhan UniversityWuhan 430072China

This paper outlines the initial steps and basic framework for developing foundation/infrastructure robots/robotics based on foundation models and parallel intelligence,as well as the potential applications of new art... 详细信息

关键词： artificial foundation intelligence

Adhesion Performances Between Two Orthotropic Solids Influenced by Temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： Qing-hui Luo yue-Ting Zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models belong to isothermal adhesion theories,where the effect of temperature on adhesion was ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,which are solved analytically with the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors between orthotropic solids is *** is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model Temperature Griffith energy balance

Nanopore design of sulfur doped hollow carbon nanospheres for superior potassium-ion battery anodes

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Rare Metals 2024年第5期43卷 2103-2114页

作者： Zhen-Dong Liu hui-Yan Feng Yu-Chen Wang Fei Wang yue Liu Jian-Xiao Yang yue Gu jun Tan Chong Ye Cheng-Zhi Zhang Ji Hua Laboratory Foshan 528000China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology College of Materials Science and EngineeringHunan UniversityChangsha 410082China

Sulfur doped carbonaceous materials are promising anodes for potassium-ion batteries because of their ability to bridge active sites and induce C/S electron coupling,resulting in increased ion storage capacitance However,the large potassium ions could cause significant volume expansion and structure collapse during operation in sulfur doped carbonaceous anodes,which lead to rapidly capacity sacrifice during long-term *** design for anchoring sulfur atom in carbon skeleton is a novel way to alleviate the structure collapse and maintain the cycling ***,this study developed a controlled nanopore and sulfur doped carbon sphere structure(S-NPHCSs).In potassium-ion batteries S-NPHCSs anode demonstrated exceptional performance with a high reversible capacity of 247 mAh·g^(–1)after 50 cycles at 0.2 A·g^(–1)and delivered a long cycle stability of 600 cycles at a high current density of 1.0 A·g^(–1).Interconnected nanopores and doped sulfur structure not only expand the accumulation space and offer ample active sites for diffusion and adsorption of potassium ions,but also build stable channels through nanopore structure to ensure the cyclic *** finding provides a fundamental theory for designing nanopore structures and introducing sulfur doped carbonaceous materials to enhance capacitive potassium storage and long cycle stability.

关键词： Nanopore Carbon materials Sulfur doping Anode Potassium-ionbatteries

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

Performance of beam size monitor based on Kirkpatrick–Baez mirror at SSRF

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Nuclear Science and Techniques 2018年第10期29卷 236-244页

作者： De-Chong Zhu jun-hui yue Yan-Feng Sui Da-Heng Ji Jian-She Cao Kai-Rong Ye Shun-Qiang Tian Jie Chen Yong-Bin Leng 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 Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

High-energy photon source(HEPS) is a 6 GeV ultralow emittance storage ring light source to be built in Beijing, China. Both the horizontal and vertical beam sizes of the HEPS storage ring are below 10 lm. It is a challenge to measure such a small beam size in both directions. To this end, measurement by a Kirkpatrick–Baez(KB) mirror imaging system was evaluated. A test KB system for the Shanghai Synchrotron Radiation Facility storage ring was designed and tested. Two crossed cylindrical mirrors were used to image the dipole source point. Both mirrors can be moved in and out so that the monitor is interchangeable with the original X-ray pinhole monitor. The aberration and point spread function, which would cause image blur, were evaluated. A beam-based calibration scheme was used by varying the beam size with different quadrupole settings and fitting them with the corresponding theoretical *** updated the original X-ray camera with a new camera having a 5-lm-thick LuAG/Ce scintillator, and the imaging result shows greatly decreased image blur.

关键词： KB mirror Beam size measurement Beam diagnostic Emittance Synchrotron radiation

MoS2 as a cocatalyst applied in advanced oxidation processes for enhancing degradation of organic pollutants: a review

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Tungsten 2024年第3期6卷 473-487页

作者： Ming-Hao Fan Cong-hui Wang Xiang Yu jun Ding Ao-Qi Xiao yue Li Wei-Ya Huang School of Material Science and Engineering Henan Polytechnic University School of Chemical and Printing-Dyeing Engineering Henan International Joint Laboratory of Rare Earth Composite Materials Henan University of Engineering School of Chemistry and Chemical Engineering Jiangxi University of Science and Technology Department of Chemical and Environmental Engineering University of Cincinnati

Fenton technology,as a typical advanced oxidation processes（AOPs）,can generate reactive oxygen species（ROS） of strong oxidation capacity to degrade organic pollutants,which has attracted wide ***,it is accompanied by the slow Fe3+/Fe2+cycle rate,easy to generate iron sludge and so ***,it has been proven that the inorganic cocatalysts represented by MoS2can effectively solve the above ***,MoS2can accelerate the activation of peroxy mono sulfate（PMS） and peroxodisulfate（PDS） by Fe2+.In this paper,MoS2as the cocatalyst in H2O2+Fe2+,PMS+Fe2+and PDS+Fe2+were comprehensively ***,the cycling processes of Fe3+/Fe2+in different systems,the cocatalytic effect of MoS2by the exposed active sites,the ROS generation mechanism as well as the microscopic mechanism during the reaction were elaborated *** results indicate that the reductive active sites on the surface of MoS2can promote the regeneration of Fe2+through the cycle between Fe3+/Fe2+and Mo4+/Mo5+/Mo6+.Thus,ROS such as ·OH,SO4·-and1O2with strong oxidizing property can be produced to improve the degradation efficiency of organic *** last,the challenges and developments of MoS2cocatalysts in AOPs for practical applications were *** review contributes to a deeper understanding of the cocatalytic effect of two-dimensional metal sulfides in AOPs and facilitates their industrial application.

关键词： Cocatalyst Fenton reaction Degradation of organic pollutant Molybdenum disufide Reactive oxygen species