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Muon anomalous Muon anomalous Muon anomalous magnetic dipole moment in theμνSSM

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Chinese Physics C 2022年第9期46卷 103-114页

作者： Hai-Bin Zhang Chang-Xin Liu jin-lei yang Tai-Fu Feng Department of Physics Hebei UniversityBaoding 071002China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding 071002China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China College of Physics Chongqing UniversityChongqing 400044China Department of Physics Guangxi UniversityNanning530004China

Recently,the Muon g-2 experiment at Fermilab measured the muon anomalous magnetic dipole moment(MDM),aμ=(gμ-2)/2,and reported that the new experimental average increases the difference between the experiment and the standard model(SM)prediction to 4.2σ.In this work,we reanalyze the muon anomalous MDM at the two-loop level in theμfrom theνSupersymmetric Standard Model(μνSSM)combined with the updated experimental ***μνSSM can explain the current difference between the experimental measurement and the SM theoretical prediction for the muon anomalous MDM,constrained by the 125 GeV Higgs boson mass and decays,the rare decayˉB→Xsγ,and so *** also investigate the anomalous MDM of the electron and tau lepton,ae=(ge-2)/2 and aτ=(gτ-2)/2,at the two-loop level in theμν*** addition,the decaying of the 125 GeV Higgs boson into a pair of charged leptons in theμνSSM is analyzed.

关键词： supersymmetry magnetic dipole moment Higgs boson decays

Catalytic Reaction Kinetics of Propylene Dimerization to 4-Methyl-1-Pentene Using Cu-K/K_(2)CO_(3) Solid Base Catalyst

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 78-87页

作者： jin Haibo Chai jing yang Suohe He Guangxiang Ma lei Guo Xiaoyan College of New Materials and Chemical Engineering Beijing Institute of Petrochemical Technology/Beijing Key Laboratory of Fuel Cleaning and Efficient Catalytic Emission Reduction TechnologyBeijing102617China

The catalysis technology of propylene dimerization to form 4-methyl-1-pentene(4MP1)using a Cu-K/K_(2)CO_(3) solid base catalyst is a well-known heterogeneous catalytic *** this study,the intrinsic kinetics of propylene dimerization were studied in a fixed-bed continuous *** and external diffusion during the dimerization reaction experiments were eliminated by adjusting the flow rate of the carrier gas and the particle size of the catalyst ***,the concentration changes of each substance at the outlet of the catalyst bed under different residence times were ***,the suitable reaction kinetics equations was derived using the Langmuir Hinshelwood-Hougen-Watson kinetic ***,the activation energy for each reaction involved in the dimerization reaction was *** activation energies of 4MP1,branched by-products,and 1-hexene were 115.0,150.8,and 177.4 kJ/mol,*** effect of process conditions on propylene dimerization with solid base catalysts was studied through kinetic model *** comparing the theoretical values obtained from the simulation with the experimental results,the applicability and accuracy of the kinetic model were verified.

关键词： propylene dimerization 4-methyl-1-pentene intrinsic kinetics surface reaction

Tuning interfacial charge transfer for efficient visible-light-driven photodegradation and simultaneous H_(2)evolution

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Journal of Materials Science & Technology 2024年第1期168卷 35-49页

作者： Zhiyang Li Yaogang Chen Yinghe Zhang Wei Ai Qian lei Tingjun Yao Dan Zhong Wenjie Liu Wenbiao jin lei yang State Key Laboratory of Urban Water Resource and Environment Shenzhen Key Laboratory of Organic Pollution Prevention and ControlSchool of Civil and Environmental EngineeringHarbin Institute of Technology ShenzhenShenzhen 518055China Key Laboratory of Northwest Water Resources Environment and EcologyMinistry of EducationSchool of Environmental and Municipal EngineeringXi’an University of Architecture and TechnologyXi’an 710055China CNAS Accredited Test Center Guangdong Engineering Technology Research Center of Air PurificationHealthlead Co.Ltd.Shenzhen 518055China School of Science Harbin Institute of Technology ShenzhenShenzhen 518055China

The edge-graphitized carbon nitride(C_(3)N_(4)-C g)was prepared by secondary pyrolysis to construct ZnO/C_(3)N_(4)-C g(ZCN)type-Ⅱheterojunction photocatalyst via a facile sonication dispersion method,which achieved∼7.04-fold and∼18.3-fold enhanced visible-light-driven photocatalytic performance for refrac-tory micropollutant removal and simultaneous hydrogen(H_(2))evolution respectively compared to con-ventional ZnO/g-C_(3)N_(4)Step-scheme *** apparent quantum efficiency of the ZCN_(0.4)het-erojunction reaches 0.92%(λ=420 nm).Such excellent performance stems from that the edge-graphene moieties stitched onto the interface of heterojunction extend light absorption to the full visible spec-trum,meanwhile,the built-in electric field generated during Fermi level alignment accompanying fa-vorable band-bending structure provides an effective pathway for the rapid migration of photoinduced electrons via the edge graphene channel to improve interfacial charge separation ***,the midgap states introduced in ZCN heterojunction could temporarily retain photoexcited electrons to effectively inhibit the in situ carrier recombination for improved photocatalytic H_(2)***,ZCN/peroxymonosulfate system exhibited excellent anti-interference performance against complex water bodies under visible illumination due to the synergistic effect between the co-existing anions and organic ***,the eco-friendly nature of the ZCN/peroxymonosulfate system showed no biotoxicity of reaction filtrate on cell proliferation after treatment,which avoided secondary ***-ering the outstanding performance in photocatalysis,the ZCN system exhibits broad potential for practical applications in water pollution control and green energy production.

关键词： ZnO C_(3)N_(4)-C g Heterojunction Photodegradation Hydrogen evolution

Evolution of inclusions in vacuum induction melting of superalloys containing 70%return material

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Journal of Iron and Steel Research International 2024年第3期31卷 719-728页

作者： jin-guo Gao Shu-lei yang Shu-feng yang jing-she Li Wei Liu Meng-jing Zhao An-ren Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Metallurgical and Building Materials Business Department China International Engineering Consulting CorporationBeijing 100048China

The variation law of inclusions type and size in the vacuum induction melting process and ingot of Ni-based superalloy containing 70%return material was studied by industrial test sampling,and the mechanism of inclusions formation was analyzed with thermodynamic *** results show that there are mainly two types of composite inclusions in the vacuum induction melting of Ni-based superalloys,which are nitride-and oxide-based composite inclusions,like Al_(2)O_(3)-SiO_(2)-Cr_(2)O_(3),TiN-(Mo,Nb)C,*** type and proportion of inclusions from the center to the edge of the vacuum induction ingot did not change *** number density of inclusions from the center to the edge of the ingot varied less,and the size of inclusions became smaller from the center to the *** addition,thermodynamic calculations show that oxides(M_(2)O_(3))are present in the liquid phase and mainly contain Al,Ti,Cr,Fe and O *** nitride consists mainly of Ti and N and contains small amounts of Cr,C,Nb,and Mo *** is consistent with the results of industrial *** the temperature decreases,the precipitation phases such as M_(2)O_(3),MN,γ,MC,δ,γ'andμphases are gradually precipitated,where oxides and nitrides are present in the liquid *** contents of O and N elements are the main influencing factors for the inclusions content and precipitation temperature;when the nitrogen content is reduced to below 0.0015%,it can make MN precipitate below the liquid-phase line.

关键词： Ni-based superalloy Vacuum induction melting Return material Inclusion Thermodynamic

Comparative Experimental Study on Heat Transfer Characteristics of Building Exterior Surface at High and Low Altitudes

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Journal of Thermal Science 2024年第3期33卷 1119-1131页

作者： JIA Yonghong GUO Shurui LI jin GUO lei CHENG Zhu ZHANG Yin yang Hanyu LONG Enshen Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu610065China

The external surface heat transfer coefficient of building envelope is one of the important parameters necessary for building energy saving design,but the basic data in high-altitude area are ***,the authors propose a modified measurement method based on the heat balance of a model building,and use the same model building to measure its external surface heat transfer coefficient under outdoor conditions in Chengdu city,China at an altitude of 520 m and Daocheng city at an altitude of 3750 m *** results show that the total heat transfer coefficient(h_(t))of building surface in high-altitude area is reduced by 34.48%.The influence of outdoor wind speed on the convective heat transfer coefficient(h_(c))in high-altitude area is not as significant as that in low-altitude *** fitting relation between convection heat transfer coefficient and outdoor wind speed is also *** the same heating power,the average temperature rise of indoor and outdoor air at highaltitude is 41.9%higher than that at low altitude,and the average temperature rise of inner wall is 25.8%higher than that at low *** shows that high-altitude area can create a more comfortable indoor thermal environment than low-altitude area under the same energy consumption *** is not appropriate to use the heat transfer characteristics of the exterior surface of buildings in low-altitude area for building energy saving design and related heating equipment selection and system terminal matching design in high-altitude area.

关键词： altitude heat transfer characteristics convective heat transfer coefficient(h_(c)) radiative heat transfer coefficient(h_(r)) external building envelope

Inhibiting shuttle effect of lithium polysulfides by double metal selenides for high-performance lithium-sulfur batteries

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Rare Metals 2024年第6期43卷 2546-2559页

作者： lei Li Xue-jing yang Yi-yang Li Bo jin Hui Liu Meng-yang Cui Dong-Bo Guan Xing-You Lang Qing Jiang Key Laboratory of Automobile Materials Ministry of Educationand College of Materials Science and EngineeringJilin UniversityChangchun 130022China

Lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production ***,the low electronic conductivity of active material and shuttling effect of lithium polysulfides(LiPSs)limit the commercial development of *** solve these problems,we design a core-shell composite with nitrogen-doped carbon(NC)and two types of selenides(FeSe_(2)-NC@ZnSe-NC).The FeSe_(2)-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb *** the same time,it also effectively alleviates the shuttling effect of LiPSs,and improves the utilization of the active substance during the charge/discharge reaction *** mechanism involved in FeSe_(2)-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory(DFT)*** electrochemical test results indicate that LSB with S/FeSe_(2)-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g^(-1)at *** after 500 cycles at 1C,the capacity decay rate per cycle is 0.031%,and the capacity retention rate is 85%.The FeSe_(2)-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.

关键词： Lithium-sulfur batteries Shuttling effect Metal selenide Nitrogen-doped carbon Lithium polysulfides

Extended finite element-based cohesive zone method for modeling simultaneous hydraulic fracture height growth in layered reservoirs

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2960-2981页

作者： lei yang Baixi Chen Hopkins Extreme Materials Institute Johns Hopkins UniversityBaltimoreMD21218USA School of Civil Engineering The University of SydneyNSW2006Australia Department of Mechanical Engineering University of Wisconsin-Madison1513 University AvenueMadisonWI53706-1572USA Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

In this study,a fully coupled hydromechanical model within the extended finite element method(XFEM)-based cohesive zone method(CZM)is employed to investigate the simultaneous height growth behavior of multi-cluster hydraulic fractures in layered porous reservoirs with modulus *** coupled hydromechanical model is first verified against an analytical solution and a laboratory ***,the fracture geometry(***,aperture,and area)and fluid pressure evolutions of multiple hydraulic fractures placed in a porous reservoir interbedded with alternating stiff and soft layers are investigated using the *** stress and pore pressure distributions within the layered reservoir during fluid injection are also *** simulation results reveal that stress umbrellas are easily to form among multiple hydraulic fractures’tips when propagating in soft layers,which impedes the simultaneous height *** is also observed that the impediment effect of soft layer is much more significant in the fractures suppressed by the preferential growth of adjoining *** that,the combined effect of in situ stress ratio and fracturing spacing on the multi-fracture height growth is presented,and the results elucidate the influence of in situ stress ratio on the height growth behavior depending on the fracture ***,it is found that the inclusion of soft layers changes the aperture distribution of outmost and interior hydraulic *** results obtained from this study may provide some insights on the understanding of hydraulic fracture height containment observed in filed.

关键词： Hydraulic fracturing Layered reservoir Simultaneous height growth In situ stress Fracture spacing Extended finite element method(XFEM) Cohesive zone method(CZM)

The Short-Duration Heavy Rainfall in Different Quadrants of Northeast China Cold Vortices

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Journal of Meteorological Research 2024年第2期38卷 321-338页

作者： lei yang Yongguang ZHENG Liaoning Meteorological Disaster Monitoring and Early Warning Center Shenyang 110166 National Meteorological Centre China Meteorological AdministrationBeijing 100081 China Meteorological Administration Tornado Key Laboratory Foshan 528315

The Northeast China cold vortex(NCCV)is one of the main synoptic-scale systems causing short-duration heavy rainfall(SDHR)in Northeast *** conditions(e.g.,water vapor,instability,and vertical wind shear)are known to be distinctly different over the four quadrants of NCCVs,rendering prediction of the SDHR related to NCCVs(NCCV_SDHR)more *** on 5-yr hourly rainfall observations from 3196 automatic weather stations and ERA5 reanalysis data,10,232 NCCV_SDHR events were identified and divided into four quadrant groups according to their relative position to the center of the NCCV(CVC).The results show that the southeast quadrant features the highest frequency of SDHR,with stronger intensity,longer duration,and wider coverage;and the SDHR in different quadrants presents different formation mechanisms and varied temporal evolution.A new coordinate system is established relative to the CVC that uses the CVC as the origin and the radius of the NCCV(r CV)as the unit *** this new coordinate system,all of the NCCV_SDHR events in the 5-yr study period are *** is found that the occurrence frequency of NCCV_SDHR initially increases and then decreases with increasing distance from the *** highest frequency occurs mainly between 0.8 and 2.5 times r CV from the CVC in the southeast *** can be attributed to the favorable conditions,such as convergence of the low-level shear line and abundant water vapor,which are concentrated in this ***,high-frequency NCCV_SDHR larger than 50 mm(NCCV_SDHR50)is observed to be closer to the *** NCCV_SDHR50occurs,the NCCV is in closer proximity to the subtropical high,resulting in stronger low-level convergence and more abundant water ***,there are lower lifting condensation levels and stronger 0-6-and 0-1-km vertical wind shears in these *** findings provide a valuable reference for more accurate prediction of NCCV_SDHR.

关键词： Northeast China cold vortex short-duration heavy rainfall statistical characteristics environmental conditions

Improvement of the piezoelectricity of PVDF-HFP by CoFe_(2)O_(4)nanoparticles

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Nano Materials Science 2024年第2期6卷 201-210页

作者： Dan lei Ning Hu Liangke Wu Alamusi Huiming Ning yang Wang Zhaonan jin Yaolu Liu College of Aerospace Engineering Chongqing UniversityChongqing400044China State Key Laboratory of Reliability and Intelligence Electrical Equipment School of Mechanical EngineeringHebei University of TechnologyTianjin300401China

High piezoelectric composite films composed of poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)and ferromagnetic cobalt ferrite(CoFe_(2)O_(4))(0.00 wt%to 0.2 wt%)are prepared by a solution casting method accompanied by uniaxial stretching and high electric field *** decisive effect of the poling electric field on the power generating capability was confirmed by the *** pure PVDF-HFP films,when the maximum electric field Emax is 120 MV/m,the calibrated open circuit voltage reaches 2.93 V,which is much higher than those poled at lower electric fields(70 MV/m:1.41 V;90 MV/m:2.11 V).Furthermore,the addition of CoFe_(2)O_(4)also influences the piezoelectricity *** the samples containing 0.15 wt%CoFe_(2)O_(4),the calibrated open circuit voltage increases to the maximum value of 3.57 ***,the relative fraction of theβ-phase and the crystallinity degree are 99%and 48%,*** effects of CoFe_(2)O_(4)nanoparticles on initial crystallization,uniaxial stretching and high electric field poling are investigated by XRD,FTIR and DSC.

关键词： PVDF-HFP CoFe_(2)O_(4)nanoparticles Piezoelectricity Nanocomposite