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Estimating the production rates of D-wave charmed mesons via the semileptonic decays of bottom mesons

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Chinese Physics C 2019年第2期43卷 53-76页

作者： Kan Chen hong-wei ke Xiang Liu Takayuki Matsuki School of Physical Science and Technology Lanzhou University Research Center for Hadron and CSR Physics Lanzhou University and Institute of Modern Physics of CAS School of Science Tianjin University Tokyo Kasei University Theoretical Research Division Nishina CenterRIKEN

Using the covariant light-front approach with conventional vertex functions, we estimate the production rates of D-wave charmed/charmed-strange mesons via the B_((s)) semileptonic decays. As the calculated production rates are significant, it seems possible to experimentally search for D-wave charmed/charmed-strange mesons via semileptonic decays, which may provide an additional approach for exploring D-wave charmed/charmed-strange mesons.

关键词： light-front quark model semileptonic decay charmed/charmed-strange meson

Study on the possible molecular state composed of D^∗sD^¯s1 within the Bethe-Salpeter framework

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Chinese Physics C 2020年第9期44卷 40-52页

作者： hong-wei ke Xiao-Hai Liu Xue-Qian Li School of Science Tianjin UniversityTianjin 300072China School of Physics Nankai UniversityTianjin 300071China

Recently,a vector charmonium-like state Y(4626)was observed in the portal of D+sDs1(2536)−.This intrigues an active discussion on the structure of the resonance because it has obvious significance for gaining a better understanding on its hadronic structure that contains suitable inner ***,this observation concerns the general theoretical framework about possible structures of exotic *** the mass of Y(4626)is slightly above the production threshold of D+sDs1(2536)−,whereas it is below that of D^∗sD^¯s1(2536)with the same quark contents as that of D+sDs1(2536)−,it is natural to conjecture that Y(4626)is a molecular state of D^∗sD^¯s1(2536),as suggested in the *** or negating this allegation would shed light on the goal we are concerned *** calculate the mass spectrum of a system composed of a vector meson and an axial vector i.e.,D^∗sD^¯s1(2536)within the framework of the Bethe-Salpeter *** numerical results show that the dimensionless parameterλin the form factor,which is phenomenologically introduced to every vertex,is far beyond the reasonable range for inducing even a very small binding energyΔ*** implies that the D^∗sD^¯s1(2536)system cannot exist in the nature as a hadronic molecule in this ***,we may not be able to assume the resonance Y(4626)to be a bound state of D^∗sD^¯s1(2536),and instead,it could be attributed to something else,such as a tetraquark.

关键词： molecular states Bethe-Salpeter equation strong decay

Expression and Characterization of a Thermostable Xylanase Gene xynA from a Themophilic Fungus in Pichia pastoris

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Agricultural Sciences in China 2011年第3期10卷 343-350页

作者： ZHAO Nan GUO Run-fang YU hong-wei, ke Xiao-jing, JIA Ying-min ke Xiao-jing JIA Ying-min BAIYu Department of Bioengineering College of Food Science and Technology Hebei Agricultural University Baoding 071001 P.R.China

The gene of xylanase （xynA） was amplified by RT-PCR from the total RNA of a themophilic fungus Thermomyces lanuginosus SY2. The sequence analysis showed that gene coding region of mature peptide contained 0.585 kb, which coded 194 amino acids. The putative amino acid sequence and DNA sequence of xylanase from T. lanuginosus SY2 （GenBank no.： GU166389） were 98.97 and 99.49% identical to the other T. lanuginosus （GenBank no.： U35436）. A recombinant plasmid pPIC9K-xynA was constructed by inserting gene xynA into Pichia pastoris secretory vector pPIC9K. Linearized pPIC9K-xynA was transformed into P. pastoris GS115 with the method of electroporation. The recombinant strain was identified by G418 selection and confirmed by PCR analysis. It was induced by 1.0% methanol at 28°C to express the recombinant xylanase. The results showed that the recombinant xylanase was secreted into extracellular fermentation liquid. The highest enzyme activity of 113.5 IU mL-1 and protein content of 889.7 μg mL-1 were detected for 216 h of induction. The optimal pH value and temperature of the enzyme activity was 5.5 and 65°C, respectively. The xylanase activity retained above 80% from pH value 2.5 to 8.5 for 48 h. The enzyme activity was above 85% at incubation temperature of 55°C.

关键词： Thermomyces lanuginosus xylanase Pichia pastoris expression

Weak decays ofΞ^((′))_(c)→Ξin the light-front quark model

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Chinese Physics C 2021年第11期45卷 34-44页

作者： hong-wei ke Qing-Qing Kang Xiao-Hai Liu Xue-Qian Li School of Science Tianjin UniversityTianjin 300072China School of Physics Nankai UniversityTianjin 300071China

Without contamination from the final state interactions,the calculation of the branching ratios of semileptonic decays Ξ^((′))_(c)→Ξ+e^(+)ν_(e) may provide further information about the inner structure of charmed ***,by studying such processes,one can better determine the form factors of Ξ_(c)→Ξ that can be further applied to relevant *** this study,we used the light-front quark model to carry out computations where the three-body vertex functions forΞ_(c) and Ξ are *** fit the new data of the Belle II,we re-adjusted the model parameters to obtain β_(s[sq])=1.07 GeV,which is 2.9 times larger than β_(ss)=0.366 *** value may imply that the ss pair in Ξ constitutes a more compact ***,we investigated the non-leptonic decays of Ξ^((′))_(c)→Ξ,which will be experimentally measured ***,our model will be tested in terms of consistency with the new data.

关键词： charmed baryon weak decay relativistic quark model

Revisiting the determining fraction of glueball component in f_(0) mesons via radiative decays of J/ψ

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Chinese Physics C 2021年第2期45卷 133-143页

作者： Xing-Dao Guo hong-wei ke Ming-Gang Zhao Liang Tang Xue-Qian Li College of Physics and New Energy Xuzhou University of TechnologyXuzhou 221111China School of Science Tianjin UniversityTianjin 300072China Department of Physics Nankai UniversityTianjin 300071China College of Physics Hebei Normal UniversityShijiazhuang 050024China

QCD theory predicts the existence of glueballs,but so far all experimental endeavors have failed to identify any such *** remedy this discrepancy between QCD,which has proven to be a successful theory for strong interactions,and the failure of experimental searches for glueballs,one is tempted to accept the promising interpretation that the glueballs mix with regular qq states of the same quantum *** lattice estimate of the masses of pure 0++ glueballs ranges from 1 to 2 GeV,which is the region of the f_(0)*** many authors suggest that the f_(0) mesonic series is an ideal place to study possible mixtures of glueballs and *** this paper,following the strategy proposed by Close,Farrar and Li,we try to determine the fraction of glueball components inf_(0)mesons using the measured mass spectra and the branching ratios of J/ψ radiative decays intof_(0)*** the pioneering papers by Close et al.,more than 20 years have elapsed and more accurate measurements have been done by several experimental collaborations,so it is time to revisit this interesting topic using new *** suppose f_(0)(500)and f_(0)(980)to be pure quark states,while for f_(0)(1370),f_(0)(1500)and f_(0)(1710),to fit both the experimental data of J/ψradiative decay and their mass spectra,glueball components are ***,the mass of the pure 0++ glueball is phenomenologically determined.

关键词： glueball f_(0) J/ψradiative decay

Applying the Kalman filter particle method to strange and open charm hadron reconstruction in the STAR experiment

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Nuclear Science and Techniques 2023年第10期34卷 148-157页

作者： Xin-Yue Ju Yue-Hang Leung Sooraj Radhakrishnann Petr Chaloupka Xin Dong Yury Fisyak Pavol Federic Ivan Kisel hong-wei ke Michal Kocan Spyridon Margetis Ai-hong Tang Iouri Vassiliev Yi-Fei Zhang Xiang-Lei Zhu Maksym Zyzak University of Science and Technology of China Hefei 230026China Lawrence Berkeley National Laboratory BerkeleyCA 94720USA University of Heidelberg 69120 HeidelbergGermany kent State University KentOH 44242USA Czech Technical University in Prague PragueCzech Republic Brookhaven National Laboratory UptonNY 11973USA Nuclear Physics Institute of the Czech Academy of Sciences PragueCzech Republic Goethe-Universitat Frankfurt Frankfurt am MainGermany Frankfurt Institute for Advanced Studies Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH DarmstadtGermany Tsinghua University Beijing 100084China

We applied KF Particle, a Kalman Filter package for secondary vertex finding and fitting, to strange and open charm hadron reconstruction in heavy-ion collisions in the STAR experiment. Compared to the conventional helix swimming method used in STAR, the KF Particle method considerably improved the reconstructed Λ, Ω, and D~0 significance. In addition, the Monte Carlo simulation with STAR detector responses could adequately reproduce the topological variable distributions reconstructed in real data using the KF Particle method, thereby retaining substantial control of the reconstruction efficiency uncertainties for strange and open charm hadron measurements in heavy-ion collisions.

关键词： Heavy-ion collisions Secondary vertex finding Kalman filter

Temporal Stability of Sward Dry Matter and Nitrogen Yield Patterns in a Temperate Grassland

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Pedosphere 2006年第6期16卷 735-744页

作者： XU hong-wei WANG ke J. S. BAILEY C. JORDAN A. WITHERS College of Environment and Resources Zhejiang University Hangzhou 310029 China Department of Agriculture and Rural Development Agricultural Food and Environmental Science Division Newforge Lane Belfast BT9 5PX （United Kingdom） Department of Agriculture and Rural Development Plant Testing Station 50 Houston Road Crossnacreevy Belfast BT6 9SH （United Kingdom）

The objectives of the present study were to examine the spatial patterns of sward dry matter (DM) and nitrogen (N) yields in a grass silage field at first, second, and third cuts over a 3-year period; quantify their temporal stabilities with temporal stability maps; and assess the potential for site-specific management in each pasture-growing period using classified management maps. At cut 1, the spatial patterns of DM and N yields proved to be well defined and temporally stable and were likely to be due to differences in the net N mineralization rates across the field during spring. In contrast, at cut 2, the patterns of DM production were patchy and temporally unstable. It was concluded that, in principle, a simple site-specific approach to N fertilization would be possible in this field during spring at cut 1. At later harvests, the rationale for a site-specific approach to fertilizer management was less clear with logistics appearing to be more complex and less feasible.

关键词： cool temperate grassland dry matter yield spatial variability temporal stability

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骚扰阿蚊生物学的实验室研究

昆虫学报 1989年第1期32卷 74-79页

作者：宋关鸿柯伟第二军医大学寄生虫学教研室

选育采自上海的骚扰阿蚊实验室品系,成蚊可在26×20×20cm蚊笼内饲养繁殖。该品系蚊虫在实验室养殖条件下:卵、幼虫及蛹期分别为4.02天、9.79天和3.99天。孵化、化蛹及羽化率分别为80.25％、82.66％和97.42％。成蚊的性比为1.00。喂糖... 详细信息

选育采自上海的骚扰阿蚊实验室品系,成蚊可在26×20×20cm蚊笼内饲养繁殖。该品系蚊虫在实验室养殖条件下:卵、幼虫及蛹期分别为4.02天、9.79天和3.99天。孵化、化蛹及羽化率分别为80.25％、82.66％和97.42％。成蚊的性比为1.00。喂糖水雌蚊、喂鼠血雌蚊和雄蚊的寿命分别为29.27天、61.96天和28.75天。成蚊一生平均产卵1.4次,每蚊平均产卵163.28粒。各变态期转换时间具有明显的昼夜节律,孵化和羽化主要在白昼而产卵,蜕皮及化蛹集中在黑夜。

关键词：骚扰阿蚊生物学昼夜节律

离轴平顶高斯涡旋光束形成的合成光涡旋及其在自由空间中的传输

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物理学报 2008年第9期57卷 5542-5549页

作者：闫红卫程科吕百达四川大学激光物理与化学研究所成都610064

对两束拓扑电荷m1,2=±1的平行、离轴平顶高斯涡旋光束在束腰面叠加形成的合成光涡旋及其在自由空间的传输做了研究.详细的数值计算和分析表明,合光涡旋的位置、数目和净拓扑电荷与光束的控制参数,包括相对位相,振幅比,束腰宽度比,相对... 详细信息

对两束拓扑电荷m1,2=±1的平行、离轴平顶高斯涡旋光束在束腰面叠加形成的合成光涡旋及其在自由空间的传输做了研究.详细的数值计算和分析表明,合光涡旋的位置、数目和净拓扑电荷与光束的控制参数,包括相对位相,振幅比,束腰宽度比,相对离轴参数,光束阶数,以及传输距离有关,但拓扑电荷不总是守恒.

关键词：奇点光学合成光涡旋平顶高斯涡旋光束拓扑电荷