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Probing the Non-equilibration Component of Tilting Spin Mode

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Chinese journal of nuclear physics 1994年第2期16卷 108-111页

作者： Liu, Zuhua Zhang, Huanqiao Xu, Jincheng Qian, XIng Qiao, Yu lin, chengjian Xu, Kan China Inst of Atomic Energy Beijing China

-The probabilities PNCNE of non-equilibration component of tilting spinmode have been extracted from the experimental fragment anisotropies for thesystems of 16O+232Th,19F+232Th,and 16O+238*** is found that as a function ofBf（〈L〉）/Tsad,the values of PNCNF observed experimentally and expected on the ba-sis of fission before equilibration model have opposite trends.

关键词： Fission Tilting spin mode Non-equilibration

Construction and Application of Identifier Resolution in Automotive Industrial Internet

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ZTE Communications 2020年第1期18卷 55-65页

作者： lin chengjian LIU Xinwei Foton Motor Inc. Beijing 102206China School of Electronic and Computer Engineering Peking UniversityShenzhenGuangdong 518055China

Identifier resolution system in the automotive industrial Internet is necessary for building a fully interconnected infrastructure with people,machines,factories,products and *** resolution system can not only ensure the comprehensive interconnection and efficiency of research and development,procurement,production,sales,and after-sales service in automotive industry,but also promote the integration of automotive industrial data,which facilitates the integrated development of traditional automotive manufacturing and the industrial *** paper focuses on processes and methods of building identifier resolution system for the automotive industry and summarizes the construction and development of secondary node in the automotive industrial Internet in order to explore a suitable road to a rich and completed application ecosystem.

关键词： industrial Internet identifier resolution secondary node auto industry

On the size generalizibility of graph neural networks for learning resource allocation

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Science China(Information Sciences) 2024年第4期67卷 239-254页

作者： Jiajun WU chengjian SUN Chenyang YANG Beihang University School of Electronics and Information Engineering

Size generalization is important for learning resource allocation policies in wireless systems with time-varying scales. If a neural network for learning a wireless policy is not generalizable to the size of its input, it has to be re-trained whenever the system scale changes, which hinders its practical use due to the unaffordable training costs. Graph neural networks(GNNs) have been shown with size generalization ability empirically when optimizing resource allocation. Yet, are GNNs naturally size generalizable? In this paper,we argue that GNNs are not always size generalizable for resource allocation. We find that the aggregation and activation functions of the GNNs for learning a class of wireless policies play a key role in their size generalization ability. We take the GNN with the mean aggregator, called mean-GNN, as an example to reveal a size generalization condition. To demonstrate how to satisfy the condition, we learn power and bandwidth allocation policies for ultra-reliable low-latency communications and show that selecting or pretraining the activation function in the output layer of mean-GNN can make the GNN size *** results validate our analysis and evaluate the performance of the learned policies.

关键词： size generalization graph neural networks resource allocation permutation equivariance

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质子滴线核在近垒能区的反应机制研究进展

原子核物理评论 2024年第1期41卷 141-147页

作者：尹诚杨磊林承键马南茹贾会明温培威杨峰骆天鹏常昶黄志杰段海锐杨炅和中国原子能科学研究院北京102413

质子滴线核在近垒能区的反应机制,尤其是破裂机制,是当前核物理领域的前沿热点问题。为了深入考察质子滴线核的反应动力学,基于日本东京大学的CRIB终端开展了^(8)B+^(120)Sn和^(17)F+^(58)Ni体系在近垒能区的完全运动学测量。本工作在... 详细信息

质子滴线核在近垒能区的反应机制,尤其是破裂机制,是当前核物理领域的前沿热点问题。为了深入考察质子滴线核的反应动力学,基于日本东京大学的CRIB终端开展了^(8)B+^(120)Sn和^(17)F+^(58)Ni体系在近垒能区的完全运动学测量。本工作在综述前期研究结果的基础上,首次展示了^(8)B+^(120)Sn测量中的熔合截面结果。实验设置方面,针对各自反应体系产物的特点,分别设计了高效率的硅探测器阵列STARE和基于电离室的多层望远镜阵列MITA,实现了反应产物的完全鉴别。对于质子晕核8B+120Sn体系首次实现了破裂碎片的符合测量,重构了完整的破裂过程,揭示了^(8)B出射道瞬时破裂为主的弹性破裂机制。对于质子滴线核^(17)F+^(58)Ni体系则首次实现了全反应道测量,提取了准弹、破裂和总熔合反应的信息,并发现在垒下能区存在熔合截面增强的现象。理论分析表明,这主要是由于破裂连续态的耦合效应所导致,并且8B和17F存在不同的直接反应机制,表明质子晕结构对反应机制存在显著影响。

关键词：质子滴线核库仑势垒能区反应机制

ONE-PARAMETER FINITE DIFFERENCE METHODS AND THEIR ACCELERATED SCHEMES FOR SPACE-FRACTIONAL SINE-GORDON EQUATIONS WITH DISTRIBUTED DELAY

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Journal of Computational Mathematics 2024年第3期42卷 705-734页

作者： Tao Sun chengjian Zhang Haiwei Sun School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics University of MacaoMacaoChina

This paper deals with numerical methods for solving one-dimensional(1D)and twodimensional(2D)initial-boundary value problems(IBVPs)of space-fractional sine-Gordon equations(SGEs)with distributed *** 1D problems,we construct a kind of oneparameter finite difference(OPFD)*** is shown that,under a suitable condition,the proposed method is convergent with second order accuracy both in time and *** implementation,the preconditioned conjugate gradient(PCG)method with the Strang circulant preconditioner is carried out to improve the computational efficiency of the OPFD *** 2D problems,we develop another kind of OPFD *** such a method,two classes of accelerated schemes are suggested,one is alternative direction implicit(ADI)scheme and the other is ADI-PCG *** particular,we prove that ADI scheme can arrive at second-order accuracy in time and *** some numerical experiments,the computational effectiveness and accuracy of the methods are further ***,for the suggested methods,a numerical comparison in computational efficiency is presented.

关键词： Fractional sine-Gordon equation with distributed delay One-parameter finite difference methods Convergence analysis ADI scheme PCG method

Neutron halo state of ^(13)C

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Chinese Science Bulletin 2001年第1期46卷 43-45页

作者： LIU Zuhua, lin chengjian, LI Zhichang, ZHANG Huanqiao, CHEN Baoqiu, MA Zhongyu, WU Yuewei, LIU Jiancheng & LI ShuyuanChina Institute of Atomic Energy, Beijing 102413, China China Institute of Atomic Energy Beijing China

Angular distributions for the 12C(d, p)13C transfer reactions have been measured at Ed = 11.8 MeV, and compared with those of the DWBA calculations. By means of this comparison, density distributions of the last neutron in the ground state and the first 1/2+ state of 13C are extracted. The properties of these states in 13C have also been studied in the framework of the nonlinear relativistic mean-field theory with NL-SH parameters. It is found that the first l/2+ state in 13C is a neutron halo state shown by both the experimental and theoretical density distributions of the last neutron.

关键词： transfer reaction DWBA relativistic mean-field theory nucleon density distributions neutron halo of excited state.

Decarboxylative Amination with Nitroarenes via Synergistic Catalysis

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Chinese Journal of Chemistry 2024年第4期42卷 351-355页

作者： Meiling Ding Sitian Zhou Shunruo Yao chengjian Zhu Weipeng Li Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan450001 China

In this paper,we have developed a decarboxylative amination of carboxylic acids with nitroarenes for the synthesis of secondary *** protocol is performed at mild conditions without the use of noble metals as catalysts.A wide range of structurally diverse secondary amines could be obtained in good yields(up to 94%)with good functional group *** transformation shows good to excellent selectivity,avoiding the generation of over alkylated byproducts.

关键词： Nitroarenes Amines Synergistic catalysis Carboxylic acids Radical alkylation Amination Photocatalysis Steric hindrance

Enhanced monopole transition strength from the cluster decay of ^(13)C

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Science China(Physics,Mechanics & Astronomy) 2019年第1期62卷 49-55页

作者： Jun Feng Yanlin Ye Biao Yang chengjian lin HuiMin Jia DanYang Pang ZhiHuan Li Jianling Lou QiTe Li XiaoFei Yang Jing Li HongLiang Zang Qiang Liu Wei Jiang ChenGuang Li Yang Liu ZhiQiang Chen HongYi Wu ChunGuang Wang Wei Liu Xiang Wang JingJing Li DiWen Luo Ying Jiang ShiWei Bai JinYan Xu NanRu Ma LiJie Sun DongXi Wang School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University China Institute of Atomic Energy School of Physics and Nuclear Energy Engineering Beihang University Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang University

The inelastic excitations and cluster decay of ^(13)C have been measured using the reaction,9Be(^(13)C, ^(13)C* →~9Be + α)~9Be. We observe strong excitation to the 14.3-MeV(1/2-) resonant state from the cluster-decay channel, leading to an enhanced monopole matrix element of(6.3 ± 0.6) fm^2. This large cluster-related monopole strength is a clear indication of the cluster-structure domination of this state and is consistent with the recent prediction of the orthogonality condition model(OCM). It would be interesting to further explore the three-center molecular rotational band that is initiated from the observed band-head.

关键词： inelastic excitation monopole transition cluster decay

^(17)F+^(58)Ni弹性散射和破裂反应实验装置的设计

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北京航空航天大学学报 2015年第9期41卷 1708-1713页

作者：郑垒林承键张高龙贾会明张焕乔北京航空航天大学物理科学与核能工程学院北京100191 中国原子能科学研究院核物理研究所北京102413

近库仑位垒能区弱束缚原子核的动力学效应研究是当前热点问题之一.但是由于缺乏对其实验方面的研究,没有系统性的结论,因此需要大力开展实验方面的研究工作.针对质子滴线核17F在中重靶核58Ni上的弹性散射和破裂反应设计了实验装置.根据... 详细信息

近库仑位垒能区弱束缚原子核的动力学效应研究是当前热点问题之一.但是由于缺乏对其实验方面的研究,没有系统性的结论,因此需要大力开展实验方面的研究工作.针对质子滴线核17F在中重靶核58Ni上的弹性散射和破裂反应设计了实验装置.根据反应运动学,利用蒙特卡罗程序模拟计算了散射的17F分布,以及破裂产生的16O和质子分布.根据模拟计算,得到了实验装置的参数,包括探测几何效率,覆盖的立体角,反应产物17F、16O和质子的能量沉积和几何关系等.这套装置对16O和质子的符合效率为4.7%±0.1%,这为实验的开展打好了基础.用此装置,将可以在一系列国际大科学装置上开展实验.

关键词：奇特核弹性散射破裂反应探测器模拟符合效率实验装置