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Ultrahigh spatiotemporal resolution beam signal reconstruction with bunch phase compensation

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Nuclear Science and Techniques 2024年第5期35卷 99-108页

作者： You-Ming Deng Yong-Bin Leng Xing-yi Xu Jian Chen yi-mei Zhou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of the Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

Various electromagnetic signals are excited by the beam in the acceleration and beam-diagnostic elements of a particle *** is important to obtain time-domain waveforms of these signals with high temporal resolution for research,such as the study of beam–cavity interactions and bunch-by-bunch parameter ***,a signal reconstruction algorithm with ultrahigh spatiotemporal resolution and bunch phase compensation based on equivalent sampling is proposed in this *** with traditional equivalent sampling,the use of phase compensation and setting the bunch signal zero-crossing point as the time reference can construct a more accurate reconstructed *** basic principles of the method,simulation,and experimental comparison are also *** on the beam test platform of the Shanghai Synchrotron Radiation Facility(SSRF)and the method of experimental verification,the factors that affect the reconstructed signal quality are analyzed and discussed,including the depth of the sampled data,quantization noise of analog-to-digital converter,beam transverse oscillation,and longitudinal *** results of the beam experiments show that under the user operation conditions of the SSRF,a beam excitation signal with an amplitude uncertainty of 2%can be reconstructed.

关键词： Turn-by-turn bunch phase compensation technique Equivalent sampling Signal reconstruction algorithm Ultrahigh spatiotemporal resolution SSRF

Determining beam transverse absolute position by triangulation of multi-electrode signal phase differences

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Nuclear Science and Techniques 2024年第8期35卷 38-47页

作者： Xing Yang Hong‑Shuang Wang yi‑mei Zhou Yong‑Bin Leng Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China

Accurate measurement of the transverse position of a beam is crucial in particle accelerators because it plays a key role in determining the beam *** methods for beam-position measurement rely on the detection of image currents induced on electrodes or narrow-band wake field induced by a beam passing through a cavity-type ***,these methods have *** indirect measurement of multiple parameters is computationally complex,requiring external calibration to determine the system parameters in ***,the utilization of the beam signal information is ***,this study proposes a novel method for measuring the absolute electron beam transverse *** utilizing the geometric relationship between the center position of the measured electron beam and multiple detection electrodes and by analyzing the differences in the arrival times of the beam signals detected by these electrodes,the absolute transverse position of the electron beam crossing the electrode plane can be *** method features absolute position measurement,a position sensitivity coefficient independent of vacuum chamber apertures,and no requirement for a symmetrical detector electrode *** feasibility of this method is validated through numerical simulations and beam experiments.

关键词： Electron beam bunch-by bunch diagnostics Bunch position measurement Triangulation method Bunch phase Bunch-by-bunch Transverse position Pickup signal

Bunch-length measurement at a bunch-by-bunch rate based on time–frequency-domain joint analysis techniques and its application

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Nuclear Science and Techniques 2024年第4期35卷 165-175页

作者： Hong-Shuang Wang Xing Yang Yong-Bin Leng yi-mei Zhou Ji-Gang Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage *** technique uses the time–frequency-domain joint analysis of the bunch signal to obtain bunch-by-bunch and turn-by-turn longitudinal parameters,such as bunch length and synchronous *** bunch signal is obtained using a button electrode with a bandwidth of several *** data acquisition device was a high-speed digital oscilloscope with a sampling rate of more than 10 GS/s,and the single-shot sampling data buffer covered thousands of *** bunch-length and synchronous phase information were extracted via offline calculations using Python *** calibration coefficient of the system was determined using a commercial streak ***,this technique was tested on two different storage rings and successfully captured various longitudinal transient processes during the harmonic cavity debugging process at the Shanghai Synchrotron Radiation Facility(SSRF),and longitudinal instabilities were observed during the single-bunch accumulation process at Hefei Light Source(HLS).For Gaussian-distribution bunches,the uncertainty of the bunch phase obtained using this technique was better than 0.2 ps,and the bunch-length uncertainty was better than 1 *** dynamic range exceeded 10 *** technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings.

关键词： Bunch-by-bunch diagnostic Bunch-length measurement Synchronous phase measurement Joint time–frequency-domain analysis Longitudinal instability

Simultaneous removal of sulfur dioxide and nitrogen oxide from flue gas by phosphorus sludge:The performance and absorption mechanism

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Chinese Journal of Chemical Engineering 2024年第1期65卷 212-221页

作者： Yuanyuan yin Xujun Wang Lei Xu Binbin He Yunxiang Nie yi mei Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials Kunming 650500China The Higher Educational Key Laboratory for Phosphorus Chemical Engineering of Yunnan Province Kunming 650500China

Developing low-cost and green simultaneous desulfurization and denitrification technologies is of great significance for sulfur dioxide(SO_(2))and nitrogen oxide(NO_(x))emission control at low temperatures,especially for small and medium-sized coal-fired boilers and ***,phosphorus sludge,an industrial waste from the production process of yellow phosphorus,has been developed to simultaneously eliminate SO_(2)and NO_(x)from coal-fired flue *** key factors affecting the experimental results indicate that desulfurization and denitrification efficiency of over 95%can be achieved at a low temperature of 55℃.Further,the absorption mechanism was investigated by characterizing the solid and liquid phases of the phosphorus sludge during the absorption *** efficient removal of SO_(2)is attributed to the abundance of iron(Fe^(3+))and manganese(Mn^(2+))in the ***_(2)can be rapidly catalyzed and converted to SO_(4)^(2-)by *** key to NOx removal is the oxidation of NO toward watersoluble high-valent nitrogen oxides by oxidizing reactive substances induced via yellow phosphorus,which are then absorbed by water and converted to NO_(3)^(-).Meanwhile,yellow phosphorus is oxidized to phosphoric acid(H_(3)PO_(4)).The spent absorption slurry can be reused through wet process phosphoric acid production,as it contains sulfuric acid(H_(2)SO_(4)),nitric acid(HNO_(3)),and H_(3)PO_(4).Accordingly,this is a technology with broad application prospects.

关键词： Absorption Oxidation Multiphase reaction Phosphorus sludge Yellow phosphorus Low temperature

Leakage Proof,Flame-Retardant,and Electromagnetic Shield Wood Morphology Genetic Composite Phase Change Materials for Solar Thermal Energy Harvesting

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Nano-Micro Letters 2024年第10期16卷 99-120页

作者： Yuhui Chen Yang Meng Jiangyu Zhang Yuhui Xie Hua Guo Mukun He Xuetao Shi yi mei Xinxin Sheng Delong Xie Yunnan Provincial Key Laboratory of Energy Saving in Phosphorus Chemical Engineering and New Phosphorus Materials The International Joint Laboratory for Sustainable Polymers of Yunnan ProvinceThe Higher Educational Key Laboratory for Phosphorus Chemical Engineering of Yunnan ProvinceFaculty of Chemical EngineeringKunming University of Science and TechnologyKunming 650500People's Republic of China Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006People's Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi'anShaanxi 710072People's Republic of China

Phase change materials(PCMs)offer a promising solution to address the challenges posed by intermittency and fluctuations in solar thermal ***,for organic solid-liquid PCMs,issues such as leakage,low thermal conductivity,lack of efficient solar-thermal media,and flamma-bility have constrained their broad ***,we present an innova-tive class of versatile composite phase change materials(CPCMs)developed through a facile and environmentally friendly synthesis approach,leveraging the inherent anisotropy and unidirectional porosity of wood aerogel(nanowood)to support polyethylene glycol(PEG).The wood modification process involves the incorporation of phytic acid(PA)and MXene hybrid structure through an evaporation-induced assembly method,which could impart non-leaking PEG filling while concurrently facilitating thermal conduction,light absorption,and ***,the as-prepared wood-based CPCMs showcase enhanced thermal conductivity(0.82 W m^(-1)K^(-1),about 4.6 times than PEG)as well as high latent heat of 135.5 kJ kg^(-1)(91.5%encapsula-tion)with thermal durability and stability throughout at least 200 heating and cooling cycles,featuring dramatic solar-thermal conversion efficiency up to 98.58%.In addition,with the synergistic effect of phytic acid and MXene,the flame-retardant performance of the CPCMs has been significantly enhanced,showing a self-extinguishing ***,the excellent electromagnetic shielding of 44.45 dB was endowed to the CPCMs,relieving contemporary health hazards associated with electromagnetic ***,we capitalize on the exquisite wood cell structure with unidirectional transport inherent in the development of multifunctional CPCMs,showcasing the operational principle through a proof-of-concept prototype system.

关键词： Wood PCMs MXene Solar thermal storage and conversion Flame-retardant Electromagnetic shielding

Electrocatalysis for sustainable nitrogen management:materials innovation for sensing,removal and upcycling technologies

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Science China Chemistry 2024年

作者： mei yi Hongmei Li Minghao Xie Panpan Li Zhaoyu Jin Guihua Yu Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China College of Materials Science and Engineering and College of Chemistry Sichuan University Materials Science and Engineering Program and Walker Department of Mechanical Engineering The University of Texas at Austin

The global nitrogen cycle holds immense importance due to its crucial role in supporting life, supplying vital nutrients for plant growth, preserving environmental balance, and enabling the proper functioning of ecosystems. However, human activities frequently disrupt this cycle, leading to the accumulation of nitrates and nitrites in water bodies. This accumulation causes environmental pollution and health risks. Traditional methods for treating nitrogen pollution, including biological, physical, and chemical approaches, have inherent limitations. In recent years, electrocatalysis has emerged as a promising and sustainable approach for nitrogen management. This technology offers superior efficiency, high selectivity, and environmental *** not only enables accurate detection of nitrogen pollutants in the environment but also facilitates their conversion into harmless nitrogen gas. Moreover, recent advancements have focused on the upcycling of nitrogen pollutants into valuable compounds,such as ammonia and urea. In this comprehensive review, we showcase the applications of electrocatalysis in sustainable nitrogen management. Specifically, we highlight its use in the sensing, removal, and upcycling of major nitrogen pollutants,including nitrate（NO3-）, nitrite（NO2-）, and nitric oxide（NO）. We discuss the use of catalysts, such as Pd alloys, Cu-based, and Fe-based materials, in electrochemical sensing and catalysis. Additionally, we explore recent advancements in the conversion of nitrogen pollutants into valuable compounds like ammonia and urea. The review also addresses current challenges and future opportunities in the field, including innovations in sensor and catalyst design, as well as large-scale treatment strategies. We anticipate that these perspectives will provide profound insights for effective nitrogen pollution control and sustainable utilization of nitrogen resources.

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Effects of Helicobacter pylori and Moluodan on the Wnt/β-catenin signaling pathway in mice with precancerous gastric cancer lesions

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 979-990页

作者： yi-mei Wang Zheng-Wei Luo Yu-Lin Shu Xiu Zhou Lin-Qing Wang Chun-Hong Liang Chao-Qun Wu Chang-Ping Li Department of Gastroenterology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina

BACKGROUND Helicobacter pylori(***)is the primary risk factor for gastric cancer(GC),the Wnt/β-Catenin signaling pathway is closely linked to *** has a high mortality rate and treatment cost,and there are no drugs to prevent the progression of gastric precancerous lesions to ***,it is necessary to find a novel drug that is inexpensive and preventive to against *** To explore the effects of *** and Moluodan on the Wnt/β-Catenin signaling pathway and precancerous lesions of GC(PLGC).METHODS Mice were divided into the control,N-methyl-N-nitrosourea(MNU),***+MNU,and Moluodan *** first created an *** infection model in the ***+MNU and Moluodan groups.A PLGC model was created in the remaining three groups except for the control *** was fed to mice in the Moloudan group ad *** general condition of mice were observed during the whole experiment *** tissues of mice were grossly and microscopically *** quantitative real-time PCR(qRT-PCR)and Western blotting analysis,the expression of relevant genes were *** Mice in the ***+MNU group showed the worst performance in general condition,gastric tissue visual and microscopic observation,followed by the MNU group,Moluodan group and the control ***-PCR and Western blotting analysis were used to detect the expression of relevant genes,the results showed that the ***+MNU group had the highest expression,followed by the MNU group,Moluodan group and the control *** *** can activate the Wnt/β-catenin signaling pathway,thereby facilitating the development and progression of *** suppressed the activation of the Wnt/β-catenin signaling pathway,thereby decreasing the progression of PLGC.

关键词： Helicobacter pylori Gastric cancer Wnt/β-catenin signaling pathway Moluodan

MIL-101(Cr)吸附/热脱附-气相色谱-质谱法检测苯系和氯代VOCs

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分析测试学报 2024年第6期43卷 875-882页

作者：张玉崔进梅连瑞史芯沂美天津市产品质量监督检测技术研究院天津300384

以金属有机骨架材料MIL-101(Cr)为填料构建了一种新型吸附采样管,将其与热脱附-气相色谱-质谱联用实现了15种典型苯系和氯代挥发性有机物(VOCs)的检测。结果显示,15种VOCs在0~100 ng范围内呈良好的线性关系,相关系数(r2)达到0.99以上,... 详细信息

以金属有机骨架材料MIL-101(Cr)为填料构建了一种新型吸附采样管,将其与热脱附-气相色谱-质谱联用实现了15种典型苯系和氯代挥发性有机物(VOCs)的检测。结果显示,15种VOCs在0~100 ng范围内呈良好的线性关系,相关系数(r2)达到0.99以上,检出限为0.7~1.9 ng。在5、30、70 ng添加量下,15种VOCs的平均回收率分别为86.0%~126%、91.7%~133%和77.6%~135%,相对标准偏差(RSD)分别为6.6%~18%、2.9%~20%和1.3%~20%。MIL-101(Cr)填料吸附管测试稳定性和不同批次吸附管重复性的RSD分别为0.50%~14%和0.30%~18%。MIL-101(Cr)填料吸附管基于质量更少的填料实现了对苯系和氯代VOCs更高效的吸附、富集和热脱附,有助于降低吸附采样管的气体穿透风险。该研究拓展了MOFs材料在环境检测领域的实际应用场景。

关键词：金属有机骨架 MIL-101(Cr) 热脱附-气相色谱-质谱法吸附管挥发性有机物

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入口颗粒对旋流除砂器壁面磨损的影响研究

石油化工设备 2024年第2期53卷 18-22页

作者：梅毅刘杨罗元刘祎汉正检测技术有限公司四川广汉618300

基于计算流体动力学方法,采用Fluent软件中的雷诺应力模型和颗粒随机轨道模型,选取旋流除砂器常见工作状态,数值模拟研究了颗粒入口速度在5~15 m/s、质量浓度在10~30 kg/m^(3)变化时对旋流除砂器壁面磨损的影响,得到了旋流除砂器内壁磨... 详细信息

基于计算流体动力学方法,采用Fluent软件中的雷诺应力模型和颗粒随机轨道模型,选取旋流除砂器常见工作状态,数值模拟研究了颗粒入口速度在5~15 m/s、质量浓度在10~30 kg/m^(3)变化时对旋流除砂器壁面磨损的影响,得到了旋流除砂器内壁磨损分布规律。模拟结果表明,旋流除砂器壁面磨损分布并不均匀,入口环形空间以及底流口附近磨损率较大。颗粒入口速度和质量浓度的变化对旋流除砂器壁面磨损整体分布影响较小,但入口速度的变化会改变各磨损区域内磨损最严重点的位置,入口环形空间壁面磨损位置变化最为明显,而颗粒质量浓度的变化则对壁面磨损最严重点的位置影响较小。颗粒入口速度和质量浓度的增大都会使旋流除砂器最大磨损率增大,入口速度对旋流除砂器最大磨损率的影响比质量浓度更大。

关键词：旋流除砂器磨损颗粒入口速度质量浓度数值模拟