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Design and commissioning of Brav measurement system for SC200 superconducting cyclotron

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Nuclear Science and Techniques 2019年第6期30卷 57-62页

作者： Man-Man Xu Yun-Tao Song Gen Chen Yong-Hua Chen kai-zhong ding Heng-Bo Li Jun Wang Jian Zhou School of Mechanical and Automotive Engineering Anhui Polytechnic University Wuhu 241000 China Institute of Plasma Physics Chinese Academy of Sciences Hefei 230026 China Hefei CAS Ion Medical and Technical Devices Co. Ltd Hefei 230088 China

The SC200 proton therapy superconducting cyclotron was developed by ASIPP (Hefei, China) and JINR (Dubna, Russia). A measurement system was designed to assess the average radial component of the magnetic field (Brav) with 15 search coils in the median plane. The winding differences of the search coils affect the measurement accuracy of the Brav. Based on the electromagnetic induction principle, to measure the Brav accurately, this paper focuses on the design and commissioning of the Brav measurement system. The preliminary results confirm that the system design is reasonable and suitable. After testing the search coil at different speeds, the optimal speed was determined as 2.5 mm/s. The relative error was approximately 0.1% under the maximum radial component of the magnetic field Br of 7 G. The measurement precision was up to 1.0×10^-3, which can provide the required measurement tolerance of 3–7 G for Br in the median plane. The commissioning of the Brav measurement system is an important step for Br measurement. It can check and adjust the asymmetry of the superconducting coils (SCs).

关键词： Superconducting cyclotron Magnetic field Measurement system Commissioning

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang kai Zhang Liping ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng ding Yue Hu Jin Zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-Mei Wang Mei-Xia Tao kai-Ming Mo Xu Chen Shu-Hua zhong Elena S Shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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罐头涂料铁罐双酚A二缩水甘油醚及其衍生物迁移规律研究

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食品工业科技 2017年第1期38卷 87-91,96页

作者：黄文仇凯钟其顶吴刚孟镇高红波肖冬光天津科技大学生物工程学院天津300457 中国食品发酵工业研究院北京100015 全国食品发酵标准化中心北京100015

研究了罐头涂料铁罐双酚A二缩水甘油醚及其衍生物在特定食品模拟物中的迁移规律。采用50%(v/v)乙醇溶液为食品模拟物,应用高效液相色谱-串联质谱法进行双酚A二缩水甘油醚及其衍生物的定性定量分析,并应用基于Fick扩散第二定律的***模型... 详细信息

研究了罐头涂料铁罐双酚A二缩水甘油醚及其衍生物在特定食品模拟物中的迁移规律。采用50%(v/v)乙醇溶液为食品模拟物,应用高效液相色谱-串联质谱法进行双酚A二缩水甘油醚及其衍生物的定性定量分析,并应用基于Fick扩散第二定律的***模型和基于概率与数理统计方法的Weibull模型进行了预测。结果表明:贮存条件对迁移总量变化影响显著,温度越高越快达到平衡,迁移平衡值为1.28 mg/kg;***模型中扩散系数D与贮存温度符合阿伦尼乌斯动力学模型,该模型预测值与实验值的拟合优度(R^2)小于0.23,而Weibull模型拟合优度(R^2)能达到0.90以上。因此,Weibull模型比***模型更接近实际迁移结果,为评估涂料铁罐的安全性提供参考。

关键词：涂料铁罐双酚A二缩水甘油醚高效液相色谱-串联质谱法迁移模型

A general methodology to measure the light-to-heat conversion efficiency of solid materials

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Light(Science & Applications) 2023年第6期12卷 1051-1060页

作者： kai Gu Haizheng zhong Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic Systems School of Materials Sciences&EngineeringBeijing Institute of Technology100081 BeijingChina

Light-to-heat conversion has been intensively investigated due to the potential applications including photothermal therapy and solar energy *** a fundamental property of materials,accurate measurement of light-to-heat conversion efficiency(LHCE)is of vital importance in developing advanced materials for photothermal ***,we report a photothermal and electrothermal equivalence(PEE)method to measure the LHCE of solid materials by simulating the laser heating process with electric heating *** temperature evolution of samples during electric heating process was firstly measured,enabling us to derive the heat dissipation coefficient by performing a linear fitting at thermal *** LHCE of samples can be calculated under laser heating with the consideration of heat dissipation *** further discussed the effectiveness of assumptions by combining the theoretical analysis and experimental measurements,supporting the obtained small error within 5%and excellent *** method is versatile to measure the LHCE of inorganic nanocrystals,carbon-based materials and organic materials,indicating the applicability of a variety of materials.

关键词： solid versatile supporting

RFID-based Production Data Analysis in an IoT-enabled Smart Job-shop

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 128-138页

作者： kai ding Pingyu Jiang state key laboratory for manufacturing systems engineering xi’an jiaotong university Xi'an 710054 China

Under industry 4.0, internet of things(IoT), especially radio frequency identification(RFID) technology, has been widely applied in manufacturing environment. This technology can bring convenience to production control and production transparency. Meanwhile, it generates increasing production data that are sometimes discrete, uncorrelated, and hard-to-use. Thus,an efficient analysis method is needed to utilize the invaluable data. This work provides an RFID-based production data analysis method for production control in Io T-enabled smart *** physical configuration and operation logic of Io T-enabled smart job-shop production are firstly described. Based on that,an RFID-based production data model is built to formalize and correlate the heterogeneous production data. Then, an eventdriven RFID-based production data analysis method is proposed to construct the RFID events and judge the process command execution. Furthermore, a near big data approach is used to excavate hidden information and knowledge from the historical production data. A demonstrative case is studied to verify the feasibility of the proposed model and methods. It is expected that our work will provide a different insight into the RFIDbased production data analysis.

关键词： Data analysis internet of things(IoT) production control radio frequency identification(RFID) smart jobshop

Summer extreme precipitation patterns and synoptic-scale circulation precursors over the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1625-1638页

作者： Zhiyuan ding Yao HA zhong zhong College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In the context of global warming,the extreme summer precipitation over the Tibetan Plateau(TP)has changed *** this study,the summer(June–August)extreme precipitation on the TP was classified into three spatial types by applying the K-means clustering method to the Third Pole Region long time-series high-resolution(1/30°)precipitation dataset(TPHi Pr,1979–2020).The characteristics of the circulation anomalies and precursors corresponding to the extreme precipitation on the TP in summer during 1979–2020 were *** results showed that the summer extreme precipitation of the TP can be categorized into northwestern(NW),southeastern(SE),and southern Himalayan(HS)types based on extreme precipitation *** NW and SE types are mainly influenced by anomalous signals in the mid-to-high latitude regions upstream of them,whereas the HS type is controlled by the localized subtropical anomalous *** the 8th day before the onset of the NW type,an anomalous cyclone was observed in the western Atlantic Ocean(60°W,50°N),which triggered the west-to-east quasi-latitudinal propagation of Rossby *** the onset day of the NW type,the upper troposphere showed positive-negative-positive geopotential height anomalies along the latitudinal 40°N from the Caspian Sea,the western part of Xinjiang,to the northeastern *** entered from the Arabian Sea along the southeastern edge of the anomalous cyclone on the southwestern TP and converged in the northwestern *** to the NW type,the precursors of the SE type appeared at higher latitudes and were more *** the 8th day before the onset of the SE type,an anomalous cyclone occurred near Greenland(60°W,70°N)and excited Rossby waves propagating *** the onset day of the SE type,the upper troposphere showed negative-positive-negative geopotential height anomalies across Eurasia from the Ural Mountains and the Iranian Plateau to the northern TP in the northwest-southeast directi

关键词： Tibetan Plateau Summer extreme precipitation Atmospheric circulation anomaly Precursor Teleconnection wave train

Advanced Policy Learning Near-Optimal Regulation

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 743-749页

作者： ding Wang Xiangnan zhong IEEE the Faculty of Information Technology Beijing University of Technology and also with the Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing University of Technology the Department of Electrical Engineering University of North Texas

Designing advanced design techniques for feedback stabilization and optimization of complex systems is important to the modern control field. In this paper, a near-optimal regulation method for general nonaffine dynamics is developed with the help of policy learning. For addressing the nonaffine nonlinearity, a pre-compensator is constructed, so that the augmented system can be formulated as affine-like form. Different cost functions are defined for original and transformed controlled plants and then their relationship is analyzed in detail. Additionally, an adaptive critic algorithm involving stability guarantee is employed to solve the augmented optimal control problem. At last, several case studies are conducted for verifying the stability, robustness, and optimality of a torsional pendulum plant with suitable cost.

关键词： Adaptive critic algorithm learning control neural approximation nonaffine dynamics optimal regulation

Biocompatible organic dots with aggregation-induced emission for in vitro and in vivo fluorescence imaging

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Science China Chemistry 2013年第9期56卷 1228-1233页

作者： LI kai ding Dan ZHAO QiuLi SUN JingZhi TANG Ben zhong LIU Bin Institute of Materials Research and Engineering 3 Research Link Department of Chemical and Biomolecular Engineering National University of Singapore4 Engineering Drive 4 MOE Key Laboratory of Macromolecule Synthesis & Functionalization Institute of Biomedical MacromoleculesDepartment of Polymer Science & EngineeringZhejiang University Department of Chemistry The Hong Kong University of Science & Technology SCUT-HKUST Joint Research Laboratory State Key Laboratory of Luminescent Materials and Devices South China University of Technology

Fluorescent probes play a key role in modern biomedical research. As compared to inorganic quantum dots (QDs) composed with heavy metal elements, organic dye-based fluorescent nanoparticles have higher biocompatibility and are richer in variety. However, traditional organic fluorophores tend to quench fluorescence upon aggregation, which is known as aggregation-caused quenching (ACQ) effect that hinders the fabrication of highly emissive fluorescent nanoparticles. In this work, we demonstrate the synthesis of organic fluorescent dots with aggregation-induced emission (AIE) in far-red/near-infrared (FA/NIR) region. A conventional ACQ-characteristic fluorescent dye, 3,4:9,10-tetracarboxylic perylene bisimide (PBI), is converted into an AIE fluorogen through attaching two tetraphenylethylene (TPE) moieties. The fluorescent dots with surface folic acid groups are fabricated from PBI derivative (DTPEPBI), showing specific targeting effect to folate receptor-overexpressed cancer cells. In vivo studies also suggest that the folic acid-functionalized AIE dots preferentially accumulate in the tumor site through enhanced permeability and retention (EPR) effect and folate receptor-mediated active targeting effect. The low cyto-toxicity, good FR/NIR contrast and excellent targeting ability in in vitro/in vivo imaging indicate that the AIE dots have great potentials in advanced bioimaging applications.

关键词： aggregation-induced emission AIE dots targeted imaging fluorescence imaging