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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao zhang Yu-Hai zhang Ying Zou xiu-xiu Yang Gen zhang Feng-Shou zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

A bifunctional POM-based Cu-viologen complex with mixed octamolybdate clusters for rapid oxidation desulfurization and effective photogeneration of hydrogen

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Rare Metals 2024年第1期43卷 236-246页

作者： Lin Yang Zhong zhang Chao-Nan zhang xiu-Li Wang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell Bohai UniversityJinzhou 121013China

The design and synthesis of catalysts for the oxidation desulfurization and production of hydrogen are extremely important for solving environmental pollution and energy ***,a novel bifunctional [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)-based Cu-viologen complex H_(4)[Cu_(2)~ⅠCl_(2)(Hbcbpy)_(4)] [α-Mo_(8)O_(26)] [β-Mo8O_(26)]·H_(2)O(BHU-2,Hbcbpy=1-(4-carboxybenzyl)-4,4'-bipyridinium) was synthesized and characterized by single-crystal X-ray diffraction(XRD),infrared radiation spectra,powder X-ray diffraction(PXRD) and X-ray photoelectron spectroscopy(XPS) *** structural characteristic of BHU-2 is the presence of two types of octamolybdate clusters [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)and a new binuclear Cu~Ⅰ-Hbcbpy complex linked by Cl-bridges[Cu_(2)ⅠCl_(2)(Hbcbpy)_(4)]^(4+).BHU-2 as a heterogeneous catalyst exhibits excellent activities to the oxidation desulfurization and photocatalytic hydrogen *** room temperature,BHU-2 can catalyze 96% conversion of methyl phenyl sulfide with 98% selectivity,and the process obeys the pseudo-first-order reaction kinetic with the half-life of9.6 *** notorious 2-chloroethyl ethyl sulfide can achieve 99% conversion with 98% selectivity within only1 min at the presence of BHU-2,and the turnover frequency(TOF) is up to 7400 h^(-1).BHU-2 also exhibits high catalytic activity for the oxidation of other aromatic and aliphatic thioethers within short time at room ***,BHU-2 shows a high catalytic activity for visible-light-driven hydrogen evolution with an H_(2) evolution rate of 1677.85 μmol·g^(-1)·h^(-1) within 10 ***,the catalytic activities do not decrease evidently after three cycles,revealing the prominent structural stability and recyclability.

关键词： Polyoxometalate Metal-organic complex Viologen Oxidation desulfurization Photocatalytic hydrogen production

Linear Quadratic Optimal Control for Systems Governed by First-Order Hyperbolic Partial Differential Equations

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Journal of Systems Science & Complexity 2024年第1期37卷 230-252页

作者： xue Xiaomin XU Juanjuan zhang Huanshui School of Control Science and Engineering Shandong UniversityJinan 250061China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266000China

This paper focuses on linear-quadratic(LQ)optimal control for a class of systems governed by first-order hyperbolic partial differential equations(PDEs).Different from most of the previous works,an approach of discretization-then-continuousization is proposed in this paper to cope with the infinite-dimensional nature of PDE *** contributions of this paper consist of the following aspects:(1)The differential Riccati equations and the solvability condition of the LQ optimal control problems are obtained via the discretization-then-continuousization method.(2)A numerical calculation way of the differential Riccati equations and a practical design way of the optimal controller are ***,the relationship between the optimal costate and the optimal state is established by solving a set of forward and backward partial difference equations(FBPDEs).(3)The correctness of the method used in this paper is verified by a complementary continuous method and the comparative analysis with the existing operator results is *** is shown that the proposed results not only contain the classic results of the standard LQ control problem of systems governed by ordinary differential equations as a special case,but also support the existing operator results and give a more convenient form of computation.

关键词： Discretization-then-continuousization method first-order hyperbolic partial differential equations forward and backward partial difference equations linear quadratic optimal control.

Experimental Study on Wire Melting Control Ability of Twin-Body Plasma Arc

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 184-194页

作者： Ruiying zhang Fan Jiang Long xue School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Beijing Academy of Safety Engineering and Technology Beijing 102617China College of Mechanical and Energy Engineering Beijing University of TechnologyBeijing 100124China

The twin-body plasma arc has the decoupling control ability of heat transfer and mass transfer,which is beneficial to shape and property control in wire arc additive *** this paper,with the wire feeding speed as a characteristic quantity,the wire melting control ability of twin-body plasma arc was studied by adjusting the current separation ratio(under the condition of a constant total current),the wire current/main current and the position of the wire in the arc axial *** results showed that under the premise that the total current remains unchanged(100 A),as the current separation ratio increased,the middle and minimum melting amounts increased approximately synchronously under the effect of anode effect power,the first melting mass range remained constant;the maximum melting amount increased twice as fast as the middle melting amount under the effect of the wire feeding speed,and the second melting mass range was *** the wire current increased,the anode effect power and the plasma arc power were both factors causing the increase in the wire melting amount;however,when the main current increased,the plasma arc power was the only factor causing the increase in the wire melting *** average wire melting increment caused by the anode effect power was approximately 2.7 times that caused by the plasma arc *** minimum melting amount was not affected by the wire-torch distance under any current separation ratio *** the current separation ratio increased and reached a threshold,the middle melting amount remained constant with increasing wire-torch *** the current separation ratio continued to increase and reached the next threshold,the maximum melting amount remained constant with the increasing wire-torch *** effect of the wire-torch distance on the wire melting amount reduced with the increase in the current separation *** this study,the decoupling mechanism and ability of this innovative

关键词： Twin-body plasma arc Melting control ability Melting amount Current separation ratio

A Detailed Thermal Resistance Network Analysis of FCBGA Package

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Journal of Thermal Science 2024年第1期33卷 18-28页

作者： DANG Hao LU Yang DU Yanzheng zhang xiu zhang Qian MA Weigang zhang Xing Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Zhongxing Telecom Equipment Corporation Shanghai 201203China

Using thermal models to describe the heat dissipation process of FCBGA is a significant topic in the field of ***,the thermal resistance model considering the structure of each part of the chip is still ambiguous and rare,but it is quite desirable in *** this work,we propose a detailed thermal resistance network model,and describe it by using thermal conduction resistance and thermal spreading *** a striking FCBGA case,we calculated the thermal resistance of each part of the structure according to the temperature field simulated by *** thermal resistance network can be used to predict the temperatures in the chip under different *** example,when the power changes by 40%,the relative error of junction temperature prediction is only 0.24%.The function of the detailed thermal resistance network in evaluating the optimization space and determining the optimization direction is *** work illustrates a potential thermal resistance analysis method for electronic devices such as FCBGA.

关键词： FCBGA package thermal resistance network thermal spreading resistance junction temperature

Testing Linearity in Functional Partially Linear Models

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 875-886页

作者： Fan-rong ZHAO Bao-xue zhang School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China School of Statistics Capital University of Economics and BusinessBeijing 100070China

For the functional partially linear models including flexible nonparametric part and functional linear part,the estimators of the nonlinear function and the slope function have been studied in existing *** to test the correlation between response and explanatory variables,however,still seems to be ***,a test procedure for testing the linearity in the functional partially linear models will be proposed in this paper.A test statistic is constructed based on the existing estimators of the nonlinear and the slope ***,we prove that the approximately asymptotic distribution of the proposed statistic is a chi-squared distribution under some regularity ***,some simulation studies and a real data application are presented to demonstrate the performance of the proposed test statistic.

关键词： asymptotic theory functional partially linear model Nadaraya-Watson estimate test statistic

ContextAug:model-domain failing test augmentation with contextual information

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Frontiers of Computer Science 2024年第2期18卷 43-60页

作者： Zhuo zhang Jianxin xue Deheng YANG Xiaoguang MAO School of Information Technology and Engineering Guangzhou College of CommerceGuangzhou 511363China School of Computer and Information Engineering Institute for Artificial IntelligenceShanghai Polytechnic UniversityShanghai 201209China College of Computer National University of Defense TechnologyChangsha 410073China

In the process of software development,the ability to localize faults is crucial for improving the efficiency of *** speaking,detecting and repairing errant behavior at an early stage of the development cycle considerably reduces costs and development *** have tried to utilize various methods to locate the faulty ***,failing test cases usually account for a small portion of the test suite,which inevitably leads to the class-imbalance phenomenon and hampers the effectiveness of fault ***,in this work,we propose a new fault localization approach named *** obtaining dynamic execution through test cases,ContextAug traces these executions to build an information model;subsequently,it constructs a failure context with propagation dependencies to intersect with new model-domain failing test samples synthesized by the minimum variability of the minority feature *** contrast to traditional test generation directly from the input domain,ContextAug seeks a new perspective to synthesize failing test samples from the model domain,which is much easier to augment test *** conducting empirical research on real large-sized programs with 13 state-of-the-art fault localization approaches,ContextAug could significantly improve fault localization effectiveness with up to 54.53%.Thus,ContextAug is verified as able to improve fault localization effectiveness.

关键词： context fault localization test cases

Surface iodine and pyrenyl-graphdiyne co-modified Bi catalysts for highly efficient CO_(2) electroreduction in acidic electrolyte

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Nano Research 2024年第4期17卷 2381-2387页

作者： Min zhang Juan Wang Xin Rong xiu-Li Lu Tong-Bu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

CO_(2) electroreduction to formic acid/formate would contribute to alleviating the energy and climate *** work reports a Bi-based catalyst derived from the in-situ electroreduction of Bi_(2)O_(2)CO_(3) modified with iodine and pyrenyl-graphdiyne(PGDY)on the surface for efficient electroreduction of CO_(2) in acidic electrolyte,with a high partial current density of 98.71 mA·cm^(-2) and high Faradaic efficiency(FE)>90%over the potential range from^(-1).2 to-1.5 V *** hydrogen electrode(RHE),as well as the long-term operational stability over 240 h without degradation in H-type *** results and density function theory calculations show that the synergistic effect of surface iodine and PGDY is responsible for this active and extremely stable process of CO_(2) electroreduction via lowering the energy barriers for formation of*OCHO intermediate,suppressing the competitive HER by enhancing the concentration of both K+and CO_(2) at reaction interface,as well as preventing the dissolution and re-deposition of active Bi atoms on surface during catalytic *** work provides new insight into designing highly active and stable electrocatalysts for CO_(2) reduction.

关键词： CO_(2) reduction electrocatalysis Bi-based catalysts acidic electrolyte

Improving fault localization with pre-training

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Frontiers of Computer Science 2024年第1期18卷 247-249页

作者： Zhuo zhang Ya LI Jianxin xue Xiaoguang MAO School of Information Technology and Engineering Guangzhou College of CommerceGuangzhou 511363China Ningbo Artificial Intelligence Institute Shanghai Jiao Tong UniversityNingbo 315000China Institute for Artificial Intelligence Shanghai Polytechnic UniversityShanghai 210209China College of Computer National University of Defense TechnologyChangsha 410073China

1 Introduction For developers,fault localization is the most tedious and time-consuming *** order to reduce the burden of developers,researchers have developed various techniques to help reduce the cost of locating faults based on possibility of containing a fault in program statements[1].Among them,coverage-based fault localization is one of the most studied automated fault localization ***-based fault localization methods utilize a type of preliminary information to localize the faults in programs,which is a matrix of statements’coverage *** value of each element is 1 or 0,in which 1 means a statement is executed and 0 denotes a statement is not executed[1].

关键词： fault statement utilize