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Precise determination of the pole position of the exotic Zc（3900）

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Science China(Physics,Mechanics & Astronomy) 2024年第9期Mechanics & Astronomy) .卷 88-94页

作者： yun-hua chen Meng-Lin Du Feng-Kun Guo School of Mathematics and Physics University of Science and Technology Beijing School of Physics University of Electronic Science and Technology of China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences School of Physical Sciences University of Chinese Academy of Sciences Peng huanwu Collaborative Center for Research and Education Beihang University

We perform a unified description of the experimental data of the π+π-and J/ψπ±invariant mass spectra for e+e-→J/ψπ+π-and the D0D*-mass spectrum for e+e-→D0D*-π+at e+e-center-of-mass energies 4.23 and 4.26 *** analysis takes into account open-charm meson loops that contain triangle singularities,the J/ψπ-■ coupled-channel interaction respecting unitarity,and the strong ππ-■ final state interaction using dispersion *** analysis leads to a precise determination of the Zc（3900） pole with the pole mass and width (3880.7±1.7stat±22.4syst) MeV and (35.9±1.4stat±15.3syst) MeV,respectively,and hints at that the ■ molecular and non-molecular components are of similar importance in the Zc（3900） formation.

关键词： exotic hadrons dispersion relations final state interaction triangle singularity

Predictions of γ(4S)→h_b(1P,2P)π^+π^- transitions

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Chinese Physics C 2020年第2期44卷 42-50页

作者： yun-hua chen School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China

We study the contributions of intermediate bottomonium-like Zb states and the bottom meson loops in the heavy quark spin flip transitionsγ(4 S)→hb(1 P,2 P)π+π-.Depending on the constructive or destructive interferences between the Zb-exchange and the bottom meson loops mechanisms,we predict two possible branching ratios for each process:BRγ(4 S)→hb(1 P)π+π-≈(1.***.40.8×10^-6)or(0.5-0.20.5×10^-6),and BRγ(4 S)→(2 P)π+π-≈(7.1-1.1+1.7×10^-10)or(2.4-0.10.2×10^-10)).The contribution of the bottom meson loops is found to be considerably larger than that of the Zbexchange in the T(4 S)→hb(1 P)ππtransitions,while its decay rates are not comparable to those of heavy quark spin conservedγ(4 S)→γ(1 S,2 S)ππ*** also predict the contribution of the charm meson loops in the branch fractions ofΨ(3 S,4 S)→hc(1 P)ππ.

关键词： quarkonium exotic states nonrelativistic effective field theory

Improvement, Comparison, and Application of Field Measurement Methods for Grassland Vegetation Fractional Coverage

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Journal of Integrative Plant Biology 2005年第9期47卷 1074-1083页

作者： Xiao-Bing LI yun-Hao chen hua YANG yun-Xia ZHANG College of Resources Sciences and Technology Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education Beijing Normal University Beijing 100875 China

As one of the important vegetation parameters, vegetation fractional coverage （VFC） is more difficult to measure accurately among a good many parameters of plant communities. The temperate typical steppe in the north of China was chosen for investigation in the present study and a digital camera was used to measure herb community coverage in the field, adopting methods of ocular estimation, gridding measurement, visual interpretation, supervised classification, and information extraction of color spatial transformation to calculate the VFC of images captured by the digital camera. In addition VFC calculated by various methods was analyzed and compared VFC, enabling us to propose an effective method for measuring VFC using a digital camera. The results of the present study indicate that：（i） as two common useful and effective methods of measuring VFC with a digital camera, not only does the error of estimated values of visual estimation and supervised classification vary considerably, but the degree of automatization is very low and depends, to a great extent, on the manipulator; （ii） although the method of visual interpretation may assure the precision of the calculated VFC and enable the precision of results obtained using other methods to be determined, as far as large quantities of data are concerned, this method has the disadvantages of wasting time and energy, and the applications of this method are limited; （iii） the precision and stability of VFC calculated using the grid and node method are superior to those of visual estimation and supervised classification and inferior to those of visual interpretation, but, as for visual interpretation and supervised classification, gridding measurements are difficult to apply in practice because they are not time efficient; and （iv） in terms of the precision of calculation of the VFC, an information-extracting model based on an intensity, hue, saturation （IHS） color space-multi-component series segmentation strategy is s

关键词： color space transformation digital camera field measurement grassland vegetationfractional coverage.

A Study of ρ-ω Mixing in Resonance Chiral Theory

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Communications in Theoretical Physics 2018年第1期69卷 50-58页

作者： yun-hua chen De-Liang Yao Han-Qing Zheng School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China Instituto de Fisica Corpuscular(Centro Mixto CSIC-UV) Institutos de Investigaci6n de PaternaApartado 2208546071 ValenciaSpain Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

The strong and electromagnetic corrections toρ-ωmixing are calculated using an SU(2)version of resonance chiral theory up to next-to-leading orders in 1/N_(C)expansion,*** to our accuracy,the effect of the momentum dependence ofρ-ωmixing is incorporated due to the inclusion of loop *** analyze the impact ofρ-ωmixing on the pion vector form factor by performing numerical fit to the data extracted from e^(+)e^(-)→π^(+)π^(-)andτ→ν_(τ)2π,while the decay width ofω→π^(+)π^(-)is taken into account as a *** is found that the momentum dependence is significant in a good description of the experimental *** addition,based on the fitted values of the involved parameters,we analyze the decay width ofω→π^(+)π^(-),which turns out to be highly dominated by theρ-ωmixing effect.

关键词： Chiral Lagrangians vector mesons 1/N_(C)expansion

Momentum dependence ofρ−ωmixing in the pion vector form factor and its effect on(g−2)μ

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Chinese Physics C 2023年第10期47卷 10-21页

作者：陈云华秦梦歌 School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China

The inclusion of theρ−ωmixing effect is essential for a precise description of the pion electromagnetic form factor in the e+e−→π+π−process,which quantifies the two-pion contribution to the anomalous magnetic moment of muon aμ.In this study,we analyze the momentum dependence ofρ−ωmixing by considering loop contributions at the next-to-leading order in 1/NC expansion within the framework of resonance chiral *** revisit a previous study[***,***,and ***,***.69,1(2018)]and consider the contribution arising from the kaon mass splitting in the kaon loops and latest experimental *** perform two types of fits(with momentum-independent or momentum-dependentρ−ωmixing amplitude)to describe e+e−→π+π−andτ→ντ2πdata within the energy region of 600−900 MeV and decay width ofω→π+π−.Furthermore,we compare their *** findings indicate that the momentum-independent and momentum-dependentρ−ωmixing schemes provide appropriate descriptions of the ***,the momentum-dependent scheme exhibits greater self-consistency,considering the reasonable imaginary part of the mixing matrix elementΠρω*** the contribution to the anomalous magnetic moment of the muon,aππμ|[0.6,0.9]GeV,the results obtained from the fits considering the momentum-dependentρ−ωmixing amplitude are in good agreement with those obtained without incorporating the momentum dependence ofρ−ωmixing,within the margin of ***,based on the fitted values of the relevant parameters,we observe that the decay width ofω→π+π−is predominantly influenced by theρ−ωmixing effect.

关键词： hadron physics chiral effective theory rho-omega mixing g-2

Propagation and Dispersion Characteristics of Scholte Wave in VTI Media with the Presence of Irregular Seabed

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Journal of Earth Science 2024年第2期35卷 722-725页

作者： Xiaobo Liu yun Wang Jianlei Zhang Haifeng chen hua Zhang School of Ocean Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Polar Geology and Marine Mineral Resources China University of GeosciencesBeijing 100083China School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China Research&Development Center BGP IncCNPCZhuozhou 072751China National Engineering Research Center for Oil and Gas Exploration Computer Software Beijing 100080China

INTRODUCTION Surface waves propagating along the seafloor are general ly called Scholte waves,and were first discovered and studied in the early 1950s(Kugler et al.,2005;Buchen and Ben-Hador,1996).Scholte waves exhibit a dispersion phenomenon,which implies that their velocity varies with ***-frequency Scholte waves can propagate over long distances on the seabed with little attenuation(Bohlen et al.,2004).The particle mo tion of Scholte waves in a solid medium changes from a retro grade to a prograde ellipse(Klein et al.,2005;McMechan and Yedlin,1981).

关键词： seabed Dispersion implies

High-resolution remote thermometry based on Bi^(3+)-doped 0D zinc halide hybrids

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Science China Chemistry 2024年第8期67卷 2599-2605页

作者： Cui-Mi Shi Shu-hua Xue Jin-yun Wang Liang-Jin Xu Zhong-Ning chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science Technology Innovation Laboratory for Optoelectronic Information of ChinaFuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Developing highly sensitive optical thermometers is of great significance due to their capability to enable remote and non-contact temperature measurements, rendering them highly applicable in diverse and harsh environments. Herein we report a temperature-dependent phosphor of 0D metal halide hybrid by incorporating Bi^(3+)into the(MePPh_(3))_(2)ZnCl_(4) matrix. Through Bi^(3+)doping,the initially non-luminescent(MePPh_(3))_(2) ZnCl_(4) matrix exhibits a deep-blue emission centered at 453 nm, with a photoluminescence quantum yield(PLQY) of 5.71% and a Stokes shift of 75 nm at room temperature. Experimental characterization demonstrates that exciton-like luminescence of Bi^(3+)is mainly responsible for the blue emission. Single crystals of Bi^(3+)-doped(MePPh_(3))_(2)ZnCl_(4) show an unusual correlation between photoluminescence(PL) lifetime and temperature. Particularly, the dependence of luminescence lifetime on temperature is most remarkable in the temperature range of 80 to 100 K with an exceptional sensitivity up to 0.09 K^(-1), representing one of the best levels for thermometry based on PL decay lifetime. Our work not only provides a viable strategy for designing a novel, environmentally friendly, and stable blue emitter, but also paves the way for precise thermometric application at low temperature.

关键词： lead-free hybrids Bi^(3+)doping blue emission temperature sensing

Palladium-Carbon Composite Nanoparticle Films with Enhanced Electrocatalytic Activity for Hydrogen Peroxide Sensors

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Chinese Journal of Chemical Physics 2019年第2期32卷 218-222,I0003页

作者： yun-hua chen Wei-feng Luo Ji-an chen Jue Wang National Laboratory of Solid State Microstructures Department of Materials Science and Engineering Collaborative Innovation Centre of Advanced Microstructures Nanjing University Nanjing 210093 China Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province Yancheng Institute of Technology Yancheng 224051 China

A nanocomposite electrocatalyst was prepared with the method of cluster beam deposition of palladium nanoparticle thin lms on carbon nanoparticle supporting layers and used as sensitive nonenzyme hydrogen peroxide sensors. An enhancement on the electrocatalytic activity of the palladium nanoparticles toward H2O2 reduction was observed, which was related to the coverage of the carbon nanoparticles. With one monolayer of carbon nanoparticles, the H2O2 detection sensitivity reached the maximum, which was more than twice of that of the pure Pd nanoparticles.

关键词： Carbon nanoparticles Palladium nanoparticles Electrocatalyst Gas phase cluster beam deposition H2O2 detection

Individualized intensive insulin therapy of diabetes: Not only thegoal, but also the time

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World Journal of Diabetes 2024年第1期15卷 11-14页

作者： yun Hu Hong-Jing chen Jian-hua Ma Department of Endocrinology The Affiliated Wuxi People's Hospital of Nanjing Medical UniversityWuxi People's HospitalWuxi Medical CenterNanjing Medical UniversityWuxi 214023Jiangsu ProvinceChina Department of Endocrinology Nanjing First HospitalNanjing 210000Jiangsu ProvinceChina

Intensive insulin therapy has been extensively used to control blood glucose levels because of its ability to reduce the risk of chronic complications of *** to current guidelines,intensive glycemic control requires individu-alized glucose goals rather than as low as *** intensive therapy,rapid blood glucose reduction can aggravate microvascular and macrovascular complications,and prolonged overuse of insulin can lead to treatment-induced neuropathy and retinopathy,hypoglycemia,obesity,lipodystrophy,and insulin antibody ***,we need to develop individualized hypoglycemic plans for patients with diabetes,including the time required for blood glucose normalization and the duration of intensive insulin therapy,which deserves further study.

关键词： Diabetes Intensive therapy Insulin Treatment-induced neuropathy