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Unparticle Effects on Top Quark Pair Production at Photon Collider

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Communications in Theoretical Physics 2009年第4期51卷 707-712页

作者： li hai-Feng li hong-Lei SI Zong-Guo YANG Zhong-Juan Department of Physics Shandong University Jinan 250100 China

The unparticle effects on tt^- production at the future photon collider are investigated. Distributions of tt^- invariant mass and that for transverse momentum of top quark with respect to Standard Model and unparticle production are predicted. An odd valley with scalar unparticle contribution appears for some values of du, which is due to the big cancellation between the contribution from SM and that from unparticle. This character may be used to study the properties of scalar unparticle. Our investigations also show that scalar unparticle may play a significant role in tt^- production at the photon collider if it exists.

关键词： unparticle top quark linear collider

Water and sediment evolution in areas with high and coarse sediment yield of the Loess Plateau

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International Journal of Sediment Research 2013年第4期28卷 448-457页

作者： Jia-hong liU Guang-qian WANG hai-hong li Jia-guo GONG Jing-yi HAN State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research State Key Lab of Hydroscience and Engineering Tsinghua University

In the past few years,the amount of sediment entering the Yellow River decreased significantly in areas with high and coarse sediment yield of the Loess *** researchers considered that it was owing to the soil and water conservation project,while others believed that it was caused by the low *** observation data showed that the ultimate soil erosion modulus in 1960s could reach 150,000 t km".However some experts preferred to believe that the ultimate soil erosion modulus in 1960s was wrong due to some uncertain *** paper quantitatively analyzed the spatial-temporal evolution pattern of sediment yield in areas with high and coarse sediment yield of the Loess Plateau over the past 50 years,by simulating the precipitation-runoff and soil erosion in12 sample years with the digital watershed *** preliminary conclusions have been drawn as following:since the 1960s and 1970s,the rainstorm center had moved southward and the intensity of rainfall center became weaker and spread into dispersed rainfall distribution in areas with high and coarse sediment yield;the decrease of the amount of sediment entering the Yellow River was caused by the changes of rainfall type in recent years;the rainstorm of 1967 was concentrated in the region nearby "Shenmu-Fugu" in Shaanxi Province,and the annual maximum transport modulus(150,000 t km) measured in Bullpen Ditch of the left bank tributary between"Shenmu" and "Fugu" in 1967 is reasonable.

关键词： Areas with high and coarse sediment yield Digital watershed model Water and sediment evolution Yellow River

Chimera dynamics in nonlocally coupled moving phase oscillators

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Frontiers of physics 2019年第4期14卷 109-116页

作者： Wen-Hao Wang Qiong-lin Dai hong-Yan Cheng hai-hong li Jun-Zhong Yang School of Science Beijing University of Posts and Telecommunications Beijing 100876 China

Chimera states,a symmetry-breaking spatiotemporal pattern in nonlocally coupled dynamical units,prevail in a variety of ***,the interaction structures among oscillators are static in most of studies on chimera *** this work,we consider a population of *** agent carries a phase *** assume that agents perform Brownian motions on a ring and interact with each other with a kernel function dependent on the distance between *** agents are motionless,the model allows for several dynamical states including two different chimera states (the type-Ⅰ and the type-Ⅱ chimeras).The movement of agents changes the relative positions among them and produces perpetual noise to impact on the model *** find that the response of the coupled phase oscillators to the movement of agents depends on both the phase lag α,determining the stabilities of chimera states,and the agent mobility *** low mobility,the synchronous state transits to the type-Ⅰ chimera state for α close to π/2 and attracts other initial states *** intermediate mobility,the coupled oscillators randomly jump among different dynamical states and the jump dynamics depends on α.We investigate the statistical properties in these different dynamical regimes and present the scaling laws between the transient time and the mobility for low mobility and relations between the mean lifetimes of different dynamical states and the mobility for intermediate mobility.

关键词： chimera states Brownian motion nonlocal coupling phase oscillators

Production of light-flavor and single-charmed hadrons in pp collisions at√s=5.02 TeV in an equal-velocity quark combination model

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Chinese Physics C 2021年第11期45卷 60-71页

作者： hai-hong li Feng-lan Shao Jun Song School of Physical Science and Intelligent Engineering Jining UniversityShandong 273155China School of Physics and Physical Engineering Qufu Normal UniversityShandong 273165China

We apply an equal-velocity quark combination model to study the production of light-flavor hadrons and single-charmed hadrons at midrapidity in the pp collisions at √s= 5.02 TeV. We find that the experimental data for the pT spectra of Ω and φ exhibit the quark number scaling property, which clearly indicates the quark combination mechanism at hadronization. Experimental data for the pT spectra of p,Λ,Ξ,Ω,φ and K^(+0) are systematically described by the model. The non-monotonic pT dependence of the Ω/φ ratio is naturally explained, and we find that it is closely related to the shape of the logarithm of the strange quark pT distribution. Using the pT spectra of light-flavor quarks obtained from light-flavor hadrons and the pT spectrum of charm quarks, which is consistent with perturbative QCD calculations, the experimental data for differential cross-sections of D^(0,+), D^(+)_s), and Λ^(+)_(c) as functions of p are systematically described. We predict the differential cross-sections of Ξ^(0,+)_(c) and Ω^(0)_(c) . The ratio Ξ^(0,+)_(c) /D^0) in our model is approximately 0.16, and Ω^(0)_(c) /D^(0) is approximately 0.012, owing to the cascade suppression of *** addition, the predicted Ξ^(0,+)_(c) /D^0) ratios exhibit the non-monotonic dependence on pT in the low pT range.

关键词： hadronization quark combination mechanism heavy-flavor

Application of rare-earth element Y in refining impure copper

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 453-459页

作者： hai-hong li Xue-qin Sun Shang-zhou Zhang Qin-yi Zhao Guang-zhen Wang School of Environment and Materials Engineering Yantai University

The effects of rare-earth element Y in refining impure copper were investigated in this paper. The composition, microstructures, and corrosion resistance properties of impure copper before and after refinement with Y were investigated using direct-reading spectrometry, inductively coupled plasma atomic emission spectrometry, optical microscopy, scanning electron microscopy, and potentiodynamic polariza- tion measurements. The results show that the concentrations of impurities S, As, Sb, Bi, A1, Cd, and Se are remarkably decreased. Adding an appropriate amount of Y refines the microstructure and enhances the corrosion resistance properties of impure copper in HC1 solution via a purification effect. The formation enthalpies of compounds formed between Y and various impurity elements were calculated on the basis of Miedema＇s theory. The thermodynamic mechanisms of the refinement of impure copper by Y were also discussed.

关键词： copper refining yttrium addition impurities removal microstructure corrosion resistance

Chimera states in bipartite networks of FitzHugh-Nagumo oscillators

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Frontiers of physics 2018年第2期13卷 43-50页

作者： Zhi-Min Wu hong-Yan Cheng Yuee Feng hai-hong li Qiong-lin Dai Jun-Zhong Yang School of Science Beijing University of Posts and Telecommunications Beijing 100876 China Basic Education Department Jiangsu Aviation Technical College Zhenjiang 212134 China

Chimera states consisting of spatially coherent and incoherent domains have been observed in differ- ent topologies such as rings, spheres, and complex networks. In this paper, we investigate bipartite networks of nonlocally coupled FitzHugh-Nagumo （FHN） oscillators in which the units are allocated evenly to two layers, and FHN units interact with each other only when they are in different lay- ers. We report the existence of chimera states in bipartite networks. Owing to the interplay between chimera states in the two layers, many types of chimera states such as in-phase chimera states, an- tiphase chimera states, and out-of-phase chimera states are classified. Stability diagrams of several typical chimera states in the coupling strength-coupling radius plane, which show strong multistability of chimera states, are explored.

关键词： chimera states bipartite networks FitzHugh-Nagumo oscillators

Entangled chimeras in nonlocally coupled bicomponent phase oscillators:From synchronous to asynchronous chimeras

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Frontiers of physics 2020年第6期15卷 115-123页

作者： Qiong-lin Dai Xiao-Xuan liu Kai Yang hong-Yan Cheng hai-hong li Fagen Xie Jun-Zhong Yang School of Science Beiing University of Posts and TelecommunicationsBeijing 100876China Department of Research and Eoaluation Kaiser Permanente Southern CaliforniaPasadenaCA 91101USA

Chimera states,a symmetry-breaking spatiotemporal pattern in nonlocally coupled identical dynamical units,have been identified in various systems and generalized to coupled nonidentical *** has been shown that strong heterogeneity in the frequencies of nonidentical oscillators might be harmful to chimera *** this work,we consider a ring of nonlocally coupled bicomponent phase oscillators in which two types of oscillators are randomly distributed along the ring:some oscillators with *** w1 and others with *** this model,the heterogeneity in frequency is measured by frequency mismatch|w1-w2|between the oscillators in these two *** report that the nonlocally coupled bicomponent phase oscillators allow for chimera states no matter how large the frequency mismatch *** bicomponent oscillators are composed of two chimera states,one supported by oscillators with natural frequency wI and the other by oscillators with natural frequency *** two chimera states in two subpopulations are synchronized at weak frequency mismatch,in which the coberent oscillators in thern share similar mean phase velocity,and are desynchronized at large frequency mismatch,in which the coherent oscillators in different subpopulations have distinct mean phase *** synchronization-desynchronization transition between chimera states in these two subpopulations is observed with the increase in the frequency *** observed phenomena are theoretically analyzed by passing to the continuum limit and using the Ott-Antonsen approach.

关键词： chimera states bicomponent phase oscillators nonlocal coupling desynchronization transition

Microstructure and properties of TP2 copper tube with La microalloying by horizontal continuous casting

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China Foundry 2018年第1期15卷 31-36页

作者： Jin-hu Wu Shi-hong Zhang Yan Chen hai-hong li hong-wu Song Ming Cheng Jin-song liu Institute of Metal Research Chinese Academy of Sciences Shenvang 110016 China University of Chinese Academy of Sciences Beijing 100049. China School of Environment and Materials Engineering Yantai University Yantai 264005 China

The TP2 copper tube was prepared with La microalloying by horizontal continuous casting(HCC). The absorptivity of La and its effects on microstructure, tensile and corrosion properties of HCC TP2 copper tube were studied by means of the inductively coupled plasma optical emission spectrometer(ICP-OES), optical microscope(OM), scanning electron microscope(SEM) and potentiodynamic polarization measurements. The results show that the absorptivity of La in the HCC TP2 copper tube is about 15% under antivacuum conditions due to the good chemical activities of La. The impurity elements in copper tube such as O, S, Pb and Si can be significantly reduced, and the average columnar dendrite spacing of the copper tube can also be reduced from 2.21 mm to 0.93 mm by adding La. The ultimate tensile strength and the elongation with and without La addition are almost unchanged. However, the annual corrosion rate of the HCC TP2 copper tube is reduced from 10.18 mm·a^(-1) to 9.37 mm·a^(-1) by the purification effect of trace La.

关键词： rare earth microstructure mechanical properties corrosion resistance HCC TP2 copper tube

Constituent quark number scaling from strange hadron spectra in pp collisions at ■=13 TeV

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Chinese Physics C 2020年第1期44卷 86-98页

作者： Jian-Wei Zhang hai-hong li Feng-Lan Shao Jun Song School of Physics and Engineering Qufu Normal UniversityShandong 273165China Department of Physics Jining UniversityShandong 273155China

We show that the p_T spectra ofΩ^-andφat midrapidity in the inelastic events in pp collisions at■=13 TeV exhibit a constituent quark number scaling property,which is a clear signal of quark combination mechanism at *** use a quark combination model with equal velocity combination approximation to systematically study the production of identified hadrons in pp collisions at■=13 *** midrapidity spectra for protons,∧,Ξ^-,Ω^-,φand K~*in the inelastic events are simultaneously fitted by the *** multiplicity dependence of the yields of these hadrons are also well *** strong p_T dependence of the p/φratio is well explained by the model,which further suggests that the production of two hadrons with similar masses is determined by their quark content at *** p_T spectra of strange hadrons at midrapidity in different multiplicity classes in pp collisions at■=13 TeV are predicted for further tests of the *** midrapidity p_T spectra of soft(p_Tlisions at■=13 TeV are extracted.

关键词： strange hadron production quark combination hadronization quark-gluon plasma