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Weak decays of heavy baryons in the light-front approach

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Chinese Physics C 2018年第9期42卷 1-14页

作者： zhen-xing Zhao INPAC.Shanghai Key Laboratory for Particle Physics and Cosmology MOE Key Lahoratory for Particle PhysicsAstrophysics and CosmologySchool of Physics and AstronomyShanghai Jiao-Tong UniversityShanghai 200240China

In this work, we analyse semi-leptonic and non-leptonic weak decays of the heavy baryons： Λ_b,Ξ_b,Ωb and Λ_c,Ξ_c,Ωc. For non-leptonic decay modes, we study only the factorizable channels induced by the external Wemission. The two spectator quarks in the baryonic transitions are treated as a diquark and form factors are calculated in the light-front approach. Using the results for form factors, we also calculate some corresponding semi-leptonic and non-leptonic decay widths. We find that our results are comparable with the available experimental data and other theoretical predictions. Decay branching fractions for many channels are found to reach the level 10^（-3）~10^（-2）,which is promising for discovery in future measurements at BESIII, LHCb and Belle II. The SU（3） symmetry in semi-leptonic decays is examined and sources of symmetry breaking are discussed.

关键词： heavy baryons weak decay light-front approach

Spatial patterns of leaf nitrogen and phosphorus stoichiometry across southeast to central Tibet

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Journal of Mountain Science 2022年第9期19卷 2651-2663页

作者： WANG Wei ZHAO Jia-min xing zhen College of Resources and Environmental Sciences Tibet Agriculture&Animal Husbandry UniversityNyingchi 860000China Research institute of Tibet Plateau Ecology Tibet Agriculture&Animal Husbandry UniversityNyingchi 860000China

Leaf N and P stoichiometry in terrestrial ecosystems has been widely investigated in recent years owing to the importance of these elements in improving the predicted vegetation responses to global *** vertical distribution of leaf N and P stoichiometry has attracted increasing attention because of the dramatic changes in environmental factors at regional ***,the characteristics of leaf N and P stoichiometry in the southeast Qinghai–Tibet plateau(SET)are not clear,although this area is sensitive to global ***,we analyzed the leaf N and P concentrations in dominant plant species on natural altitudinal gradients on the Duoxiongla(DXL),Sejila(SJL),Mila(ML),and Gangbala(GBL)mountains across the SET all the way to central *** results showed that the leaf N concentrations were comparable among the regions,whereas the leaf P concentrations dramatically decreased from SET to central Tibet(CT).The leaf N concentrations were 23.6,21.3,20.8,and 22.4 g kg^(-1),and the leaf P concentrations were 2.40,2.49,1.94,and 1.59 g kg^(-1) on the SJL,DXL,ML and GBL mountains,*** leaf N/P ratios on the DXL,SJL,ML,and GBL mountains were 8.81,10.3,11.2,and 14.2,*** the increasing trend of the leaf N/P ratio from southeast Qinghai–Tibet plateau to central Tibet,N limitation might widely exist in well vegetated ecosystems in the Qinghai–Tibet plateau.

关键词： Leaf N and P concentration Southeast Tibet Stoichiometry Spatial variations

Theoretical and numerical study of hydraulic characteristics of orifice energy dissipator

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Water Science and Engineering 2010年第2期3卷 190-199页

作者： Ning HE zhen-xing ZHAO Institute of High Energy Physics CAS Beijing 100049 R R. China College of Mechanics and Materials Hohai University Nanjing 210098 P. R. China

Different factors affecting the efficiency of the orifice energy dissipator were investigated based on a series of theoretical analyses and numerical simulations. The main factors investigated by dimension analysis were identified, including the Reynolds number （Re）, the ratio of the orifice diameter to the inner diameter of the pipe （ did ）, and the ratio of distances between orifices to the inner diameter of the pipe （ LID ）. Then, numerical simulations were conducted with a k-ε two-equation turbulence model. The calculation results show the following： Hydraulic characteristics change dramatically as flow passes through the orifice, with abruptly increasing velocity and turbulent energy, and decreasing pressure. The turbulent energy appears to be low in the middle and high near the pipe wall. For the energy dissipation setup with only one orifice, when Re is smaller than 105, the orifice energy dissipation coefficient K increases rapidly with the increase of Re. When Re is larger than l05, K gradually stabilizes. As diD increases, K and the length of the recirculation region L1 show similar variation patterns, which inversely vary with diD. The function curves can be approximated as straight lines. For the energy dissipation model with two orifices, because of different incoming flows at different orifices, the energy dissipation coefficient of the second orifice （K2） is smaller than that of the first. If LID is less than 5, the K value of the LID model, depending on the variation of/（2, increases with the spacing between two orifices L, and an orifice cannot fulfill its energy dissipation function. If LID is greater than 5, K2 tends to be steady; thus, the K value of the LID model gradually stabilizes. Then, the flow fully develops, and L has almost no impact on the value of K.

关键词： orifice energy dissipator theoretical analysis numerical simulation k-ε two-equation turbulent model hydraulic characteristics

Uncertain Multidisciplinary Design Optimization on Next Generation Subsea Production System by Using Surrogate Model and Interval Method

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China Ocean Engineering 2021年第4期35卷 609-621页

作者： WU Jia-hao zhen xing-wei LIU Gang HUANG Yi School of Naval Architecture and Ocean Engineering Dalian University of TechnologyDalian 116024China

The innovative Next Generation Subsea Production System(NextGen SPS)concept is a newly proposed petroleum development solution in ultra-deep water *** definition of NextGen SPS involves several disciplines,which makes the design process *** this paper,the definition of NextGen SPS is modeled as an uncertain multidisciplinary design optimization(MDO)*** deterministic optimization model is formulated,and three concerning disciplines—cost calculation,hydrodynamic analysis and global performance analysis are *** model technique is applied in the latter two *** optimization(CO)architecture is utilized to organize the concerning disciplines.A deterministic CO framework with two disciplinelevel optimizations is proposed *** the uncertainties of design parameters and surrogate models are incorporated by using interval method,and uncertain CO frameworks with triple loop and double loop optimization structure are established *** optimization results illustrate that,although the deterministic MDO result achieves higher reduction in objective function than the uncertain MDO result,the latter is more reliable than the former.

关键词： next generation subsea production system multidisciplinary design optimization uncertain optimization collaborative optimization surrogate model interval method

Study of the Authenticity and Credibility of QQ Chat Records

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Journal of Harbin Institute of Technology(New Series) 2014年第6期21卷 63-66页

作者： zhen-xing Dong Long Chen Institute of Computer Forensics Chongqing University of Posts and Telecommunications School of Information Science and Technology Southwest Jiaotong University

Digital evidence investigation in QQ software is the current research *** order to identify the authenticity and credibility of QQ chat records,the method based on attacking QQ chat records is ***,an evaluation model on checking the authenticity of QQ chat records is *** cases on kinds of changing QQ chat records are *** challenge in identifying the authenticity of QQ chat records is ***,case study on attacking QQ chat records is proposed to check the relationship between the authenticity of QQ chat records and the difficulty of changing them.A couple of experiments on changing QQ chat records are finished to find how difficult changing records is and whether there are clues left on changing them or ***,a kind of QQ chat forensic process is presented,which can help for digital evidence investigation in the authenticity and credibility of QQ chat *** practices in QQ forensic cases show that it works well.

关键词： digital evidence investigation in QQ forensic identification QQ chat records authenticity credibility

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research International 2024年第2期31卷 329-341页

作者： Jin-sheng Liu zhen-xing xing Gong-jin Cheng Xue-yong Ding Xiang-xin Xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree Phase transformation Micromorphology Oxidation path Pore structure

Study of the s → dv■ rare hyperon decays in the Standard Model and new physics

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Chinese Physics C 2019年第9期43卷 26-32页

作者： Xiao-Hui Hu zhen-xing Zhao INPAC Shanghai Key Laboratory for Particle Physics and Cosmology MOE Key Laboratory for Particle Physics Astrophysics and CosmologySchool of Physics and Astronomy Shanghai Jiao-Tong University

FCNC processes offer important tools to test the Standard Model（SM）and to search for possible new *** this work,we investigate the s→dvv rare hyperon decays in SM and *** find that in SM the branching ratios for these rare hyperon decays range from 10-14 to *** all the errors in the form factors are included,we find that the final branching ratios for most decay modes have an uncertainty of about 5% to 10%.After taking into account the contribution from new physics,the generalized SUSY extension of SM and the minimal 331 model,the decay widths for these channels can be enhanced by a factor of 2～7.

关键词： branching ratios rare hyperon decays form factors light-front approach new physics

Relative Singularity Categories with Respect to Gorenstein Flat Modules

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Acta Mathematica Sinica,English Series 2017年第11期33卷 1463-1476页

作者： zhen xing DI Zhong Kui LIU Xiao Xiang ZHANG Department of Mathematics Northwest Normal University Department of Mathematics Southeast University

Let R be a right coherent ring and D^b（R-Mod） the bounded derived category of left R-modules. Denote by D^b（R-Mod）[GF,C] the subcategory of D^b（R-Mod） consisting of all complexes with both finite Gorenstein flat dimension and cotorsion dimension and K^b（F∩C） the bounded homotopy category of flat cotorsion left R-modules. We prove that the quotient triangulated category D^b（R-Mod）[GF,C]/K^b（F∩C,） is triangle-equivalent to the stable category GF∩C of the Frobenius category of all Gorenstein fiat and cotorsion left R-modules.

关键词： Triangle equivalence Gorenstein flat dimension cotorsion dimension stable category,derived category homotopy category

Completeness of Induced Cotorsion Pairs in Representation Categories of Rooted Quivers

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Acta Mathematica Sinica,English Series 2024年第10期40卷 2436-2452页

作者： zhen xing DI Li Ping LI Li LIANG Fei XU School of Mathematical Sciences Huaqiao UniversityQuanzhou 362021P.R.China LCSM(Ministry of Education) School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081P.R.China Department of Mathematics Lanzhou Jiaotong UniversityLanzhou 730070P.R.China Gansu Provincial Research Center for Basic Disciplines of Mathematics and Statistics Lanzhou 730070P.R.China Department of Mathematics Shantou UniversityShantou 515063P.R.China

This paper focuses on a question raised by Holm and Jorgensen,who asked if the induced cotorsion pairs(Φ(X),Φ(X)^(⊥))and(^(⊥)Ψ(Y),Ψ(Y))in Rep(Q,A)—the category of all A-valued representations of a quiver Q—are complete whenever(X,Y)is a complete cotorsion pair in an abelian category A satisfying some mild *** give an affirmative answer if the quiver Q is *** an application,we show under certain mild conditions that if a subcategory L,which is not necessarily closed under direct summands,of A is special precovering(resp.,preenveloping),thenΦ(L)(resp.,Ψ(L))is special precovering(resp.,preenveloping)in Rep(Q,A).

关键词： Rooted quiver complete cotorsion pair special precovering(preenveloping)subcategory