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Nuclear Science and Techniques 2023年第10期34卷 91-102页

作者： Yuan-Qiao Li Bao-ji Zhu Yang Lv Heng Zhu min Lin Ke-Sheng Chen Li-jun Xu China Institute of Atomic Energy Beijing 102413China National Key Laboratory for Metrology and Calibration Techniques Beijing 102413China

To enhance the accuracy of 2πα and 2πβ particle surface emission rate measurements and address the identification issues of nuclides in conventional methods, this study introduces two artificial neural network(ANN) algorithms: back-propagation(BP) and genetic algorithm-based back-propagation(GA-BP). These algorithms classify pulse signals from distinct α and β particles. Their discrimination efficacy is assessed by simulating standard pulse signals and those produced by contaminated sources, mixing α and β particles within the detector. This study initially showcases energy spectrum measurement outcomes, subsequently tests the ANNs on the measurement and validation datasets, and contrasts the pulse shape discrimination efficacy of both algorithms. Experimental findings reveal that the proportional counter's energy resolution is not ideal, thus rendering energy analysis insufficient for distinguishing between 2πα and 2πβ particles. The BP neural network realizes approximately 99% accuracy for 2πα particles and approximately 95% for 2πβ particles, thus surpassing the GA-BP's performance. Additionally, the results suggest enhancing β particle discrimination accuracy by increasing the digital acquisition card's threshold lower limit. This study offers an advanced solution for the 2πα and 2πβ surface emission rate measurement method, presenting superior adaptability and scalability over conventional techniques.

关键词： Pulse shape discrimination Artificial neural networks Alpha and beta sources Multi-wire proportional counter Surface emission rate

Study on the Surface Photovoltage and Fluorescence Properties of N, N-Bis(4-aminopheny)-1, 4 quinonenediimine Doped with H_4SiW_(12)O_(40)

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Chinese Chemical Letters 2002年第3期13卷 266-268页

作者： jian GONG ji Hua YANG Xiu jun CUI Zhong min SU Lun Yu QU Faculty of Chemistry Northeast Normal UniversityChangchun 130024

Aniline oligomer composite materials using heteropolyacid H4SiW12O40 as dopant was synthesized, and the effect of the doping concentration on the photoluminescence and surface photovoltaic properties were investigated.

关键词： Fluorescence property surface photovoltage spectra aniline oligomer heteropoly acid.

Synchronization of networked multibody systems using fundamental equation of mechanics

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Applied Mathematics and Mechanics(English Edition) 2016年第5期37卷 555-572页

作者： jun LIU jinchen ji jin ZHOU Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072China Department of Mathematics Jining UniversityQufu 273155Shandong ProvinceChina Faculty of Engineering and Information Technology University of Technology SydneyNSW 2007Australia Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai 200072China

From the analytical dynamics point of view, this paper develops an optimal control framework to synchronize networked multibody systems using the fundamental equation of mechanics. A novel robust control law derived from the framework is then used to achieve complete synchronization of networked identical or non-identical multibody systems formulated with Lagrangian dynamics. A distinctive feature of the developed control strategy is the introduction of network structures into the control requirement. The control law consists of two components, the first describing the architecture of the network and the second denoting an active feedback control strategy. A corresponding stability analysis is performed by the algebraic graph theory. A representative network composed of ten identical or non-identical gyroscopes is used as an illustrative example. Numerical simulation of the systems with three kinds of network structures, including global coupling, nearest-neighbour, and small-world networks, is given to demonstrate effectiveness of the proposed control methodology.

关键词： fundamental equation of mechanics analytical dynamics synchronization,networked multibody system gyrodynamics coordinate control

Improved Soft Abrasive Flow Finishing Method Based on Turbulent Kinetic Energy Enhancing

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Chinese Journal of Mechanical Engineering 2017年第2期30卷 301-309页

作者： jun LI Shiming ji Dapeng TAN Key Laboratory of E&M Zhejiang University of Technology of Ministry of Education and Zhejiang Province School of Information Science and Engineering Hangzhou Normal University

Soft abrasive flow（SAF） finishing can process the irregular geometric surfaces, but with the matter of low processing efficiency. To address the issue, an improved SAF finishing method based on turbulent kinetic energy enhancing is proposed. A constrained flow passage with serration cross-section is constructed to increase the turbulence intensity. Taking the constrained flow passage as the objective, a two-phase fluid dynamic model is set up by using particle trajectory model and standard k-ε turbulence model, and the flow field characteristics of the flow passage are acquired. The numerical results show that the serration flow passage can enhance the turbulence intensity, uniform the particles distribution, and increase the particle concentration near the bottom wall. The observation results by particle image velocimetry（PIV） show that the internal vortex structures are formed in flow passage, and the abrasive flow takes on turbulence concentrating phenomenon in near-wall region. The finishing experiments prove that the proposed method can obtain better surface uniformity, and the processing efficiency can be improved more 35%. This research provides an abrasive flow modeling method to reveal the particle motion regulars, and canoffer references to the technical optimization of fluid-based precision processing.

关键词： Soft abrasive flow Serration flow passage ·Kinetic energy enhancing Particle image velocimetry

Towards designing efficient catalyst for hydrogen oxidation reaction

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Rare Metals 2020年第10期39卷 1107-1109页

作者： Rui-jie Gao ji-jun Zou Key Laboratory for Green Chemical Technology of the ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

Anion exchange membrane fuel cells(AEMFCs)have attracted increasing research efforts in the past decade due to the advantageous nature of using Pt-free catalysts and cheap components that bring its cost closer to the ... 详细信息

关键词： catalyst closer designing

A Multifrequency Cloak with a Single Shell of Negative Index Metamaterials

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Chinese Physics Letters 2011年第6期28卷 134-136页

作者： LI Pei-Ning LIU You-Wen MENG Yun-ji ZHU min-jun College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016

We propose an invisibility multifrequency cloak with a single shell of negative index metamaterials(NIMs)based on the scattering cancellation cloaking *** and simulation results show that the cloak can reduce the total scattering cross section at multiple frequencies by exploiting the frequency dispersion of the permittivity and permeability *** may provide a potential way to design a multifrequency cloak.

关键词： theory visibility scattering

Abandonment and Recovery Operation of Steel Lazy-Wave Riser in Deepwater by Controlled Vessel and Cable Velocity Rate

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China Ocean Engineering 2023年第1期37卷 29-41页

作者： GU ji-jun HUANG jun GAO Lei CHEN Lei-lei jiA ji-chuan WANG Shu-jiang College of Mechanical and Transportation Engineering China University of Petroleum-BeijingBeijing 102249China CNOOC Research Institute Beijing 100028China

Evaluation of abandonment and recovery operation of steel lazy-wave riser in deepwater is presented in this *** calculation procedure includes two single continuous SLWR and cable segments, which are coupled together to form the overall mathematical model. Then the equilibrium equations of SLWR and cable are established based on minimum total potential energy principle. The coupled equations are discretized by the finite difference method and solved by Newton-Raphson technique in an iterative manner. The present method is validated by well-established commercial code OrcaFlex. Recovery methods by considering different ratios of vessel’s moving velocity to cable’s recovery velocity are evaluated to optimize the abandonment and recovery operation. In order to keep the tension more stable during the recovery process, the rate ratio before leaving the seabed is increased, and the rate ratio after leaving the seabed is reduced.

关键词： steel lazy-wave riser abandonment recovery

Identification of Quantitative Trait Loci for Lipid Metabolism in Rice Seeds

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Molecular Plant 2012年第4期5卷 865-875页

作者： jie-Zheng Ying jun-Xiang Shan ji-Ping Gao Mei-Zhen Zhu min Shi Hong-Xuan Lin National Key Laboratory of Plant Molecular Genetics and National Center for Plant Gene Research(Shanghai) Shanghai Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesThe Chinese Academy of SciencesGraduate School of the Chinese Academy of Sciences300 Fenglin RoadShanghai 200032China National Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006China

Plant seed oil is important for human dietary consumption and industrial application. The oil trait is controlled by quantitative trait loci （QTLs）, but no QTLs for fatty acid composition are known in rice, the monocot model plant. QTL analysis was performed using F2 and F2：3 progeny from a cross of an indica variety and a japonica variety. Gas chroma- tography-mass spectrometry （GC-MS） analysis revealed significant differences between parental lines in fatty acid com- position of brown rice oil, and 29 associated QTLs in F2 and/or F2：3 populations were identified throughout the rice genome, except chromosomes 9 and 10. Eight QTLs were repeatedly identified in both populations across different envi- ronments. Five loci pleiotropically controlled different traits, contributing to complex interactions of oil with fatty acids and between fatty acids. Nine rice orthologs of Arabidopsis genes encoding key enzymes in lipid metabolism co-localized with 11 mapped QTLs. A strong QTL for oleic （18：1） and linoleic （18：2） acid were associated with a rice ortholog of a gene encoding acyI-CoA：diacylglycerol acyltransferase （DGAT）, and another for palmitic acid （16：0） mapped similarly to the acyl- ACP thioesterase （FatB） gene ortholog. Our approach rapidly and efficiently identified candidate genes for mapped QTLs controlling fatty acid composition and oil concentration, providing information for improving rice grain quality by marker assisted selection.

关键词： Rice fatty acid seed oil lipid metabolism QTL.

Highly Stretchable,Compressible,Adhesive,Conductive Self-healing Composite Hydrogels with Sensor Capacity

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Chinese Journal of Polymer Science 2020年第11期38卷 1221-1229,I0007页

作者： ji-jun Wang Qiang Zhang Xing-Xiang ji Li-Bin Liu State Key Laboratory of Biobased Material and Green Papermaking School of Chemistry and Pharmaceutical EngineeringQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

The design and fabrication of conductive hydrogels with high stretchability,compressibility,self-healing properties and good adhesion remains a significant *** have fabricated composite hydrogels by random polymerization of acrylic acid(AA)and dopamine(DA)in the presence of multi-walled carbon nanotubes(MWCNTs).The π-π interaction between DA and MWCNTs makes MWCNTs stably and homogenously dispersed in *** fabricated PAA-PDA/CNT composite hydrogels possess relatively high mechanical strength(maximum Youngzs modulus:800 kPa)and can be stretched to 1280%strain and compressed to 80%*** multiple hydrogen bonding formed between functional groups of PAA-PDA and MWCNTs can effectively dissipate energy and quickly achieve *** composite hydrogels also show good adhesion and can easily adhere to various inorganic or organic *** addition,the hydrogel reveals stable strain sensitivity and can be used as skin sensors.

关键词： Hydrogels Self-healing Conductivity Sensor

Multiple exciton generation effect in photocatalytic overall water splitting

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Science China Chemistry 2024年第2期67卷 424-425页

作者： Xiaolei Guo ji-jun Zou Key Laboratory for Green Chemical Technology of ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China

This highlight is based on recent research published in Nature Energy by Li and co-workers [1] from Northwestern Polytechnology University, reporting an exceeding 100% internal quantum efficiency(IQE) in photocatalytic overall water splitting. This breakthrough promises a bright future for efficient photocatalyst design by utilizing the multiple exciton effect(MEG).

关键词： splitting effect utilizing