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Regularization dependence of pion generalized parton distributions

Chinese Physics C 2022年第6期46卷 66-87页

作者： Jin-Li Zhang guang-zhen kang Jia-Lun Ping Department of Physics Nanjing Normal UniversityNanjing 210023China School of Science Yangzhou Polytechnic InstituteYangzhou 225127China

Pion generalized parton distributions are calculated within the framework of the Nambu-Jona-Lasinio model using different regularization schemes,including the proper time regularization scheme,the three-dimensional(3D)momentum cutoff scheme,the four-dimensional momentum cutoff scheme,and the Pauli-Villars regularization ***,we check the theoretical constraints of pion generalized parton distributions required by the symmetries of quantum chromodynamics in different regularization *** diagrams of pion parton distribution functions are plotted,in addition,we evaluate the Mellin moments of generalized parton distributions,which are related to the electromagnetic and gravitational form factors of *** generalized parton distributions are continuous but not differential at x=±ξ,when considering the effect of the contact contribution term,generalized parton distributions become not continuous at x=±ξin all the four regularization *** parton distributions in impact parameter space are considered,the width distribution of u quark in the pion and the meansquaredπu are *** light-front transverse-spin distributions are studied when quark polarized in the light-front-transverse+x direction,the transverse-spin density is no longer symmetric around(bx=0,by=0),the peaks shift to(bx=0,by>0),we compare the average transverse shift1u and2u in different regularization *** light-cone energy radius rE,LC and the light-cone charge radius rc,LC are also evaluated,we found that in the proper time regularization scheme the values of these quantities were the largest,in the 3 D momentum cutoff scheme they were the smallest.

关键词： generalized parton distributions form factors parton distribution functions

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Fine tuning problem of the cosmological constant in a generalized Randall-Sundrum model

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Chinese Physics C 2020年第12期44卷 210-214页

作者： guang-zhen kang De-Sheng Zhang Li Jun Hong-Shi Zong School of Science Yangzhou Polytechnic InstituteYangzhou 225127China Department of Physics Nanjing UniversityNanjing 210093China School of Science Changzhou Institute of TechnologyChangzhou 213032China Joint Center for Particle Nuclear Physics and CosmologyNanjing 210093China State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsCASBeijing 100190China

To solve the cosmological constant fine tuning problem,we investigate an(n+1)-dimensional generalized Randall-Sundrum brane world scenario with two(n−1)-branes instead of two *** an anisotropic metric ansatz,we obtain the positive effective cosmological constantΩeff of order 10−124 and only require a solution≃50−***,both the visible and hidden branes are stable because their tensions are ***,the fine tuning problem can be solved quite ***,the Hubble parameter H1(z)as a function of redshift z is in good agreement with the cosmic chronometers *** evolution of the universe naturally shifts from deceleration to *** suggests that the evolution of the universe is intrinsically an extra-dimensional *** can be regarded as a dynamic model of dark energy that is driven by the evolution of the extra dimensions on the brane.

关键词： cosmological constant fine tuning extra dimensions Hubble parameter

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Anisotropic evolution of 4-brane in a 6D generalized Randall-Sundrum model

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Chinese Physics C 2019年第9期43卷 101-107页

作者： guang-zhen kang De-Sheng Zhang Long Du Jun Xu Hong-Shi Zong School of Science Yangzhou Polytechnic InstituteYangzhou 225127China Department of Physics Nanjing UniversityNanjing 210093China School of Science Changzhou Institute of TechnologyChangzhou 213032China School of Science Guangxi University of Science and TechnologyLiuzhou 545006China Joint Center for Particle Nuclear Physics and CosmologyNanjing 210093China State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsCASBeijing 100190China

We investigate a 6 D generalized Randall-Sundrum brane world scenario with a bulk cosmological *** stress-energy tensor Tabi on the brane is shown to be similar to a constant vacuum *** is consistent with the Randall-Sundrum model,in which each 3-brane Lagrangian yielded a constant vacuum *** adopting an anisotropic metric ansatz,we obtain the 5 D Friedmann-Robertson-Walker field *** a slightly later period,the expansion of the universe is proportional to the square root of time,t1/2,which is similar to the period of the radiation-dominated ***,we investigate the case with two a（t） and two b（t）.In a large range of t,we obtain the 3 D effective cosmological constant Λeff=-2Ω/3>0,which is independent of the integral ***,the scale factor is an exponential expansion,which is consistent with our present observation of the *** results demonstrate that it is possible to construct a model that solves the dark energy problem,while guaranteeing a positive brane tension.

关键词： brane induced cosmological constants anisotropy

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Cosmic acceleration caused by the extra-dimensional evolution in a generalized Randall-Sundrum model

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Chinese Physics C 2020年第11期44卷 213-219页

作者： guang-zhen kang De-Sheng Zhang Chao Shi Long Du Dan Shan Hong-Shi Zong School of Science Yangzhou Polytechnic InstituteYangzhou 225127China Department of Physics Nanjing UniversityNanjing 210093China School of Science Changzhou Institute of TechnologyChangzhou 213032China Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Science Guangxi University of Science and TechnologyLiuzhou 545006China Department of Physics Anhui Normal UniversityWuhu 241000China Nanjing Proton Research and Design Center Nanjing 210093China

We investigate an(n+1)-dimensional generalized Randall-Sundrum model with an anisotropic metric which has three different scale *** obtains a positive effective cosmological constant Ωeff∼10^−124(in Planck units),which only needs a solution kr≃50−80 without fine *** the visible and hidden brane tensions are positive,which renders the two branes ***,we find that the Hubble parameter is close to a constant in a large region near its minimum,thus causing the acceleration of the ***,the scale of extra dimensions is smaller than the observed scale but greater than the Planck *** may suggest that the observed present acceleration of the universe is caused by the extra-dimensional evolution.

关键词： Hubble parameter extra dimensions anisotropic

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Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑Yuan Yu Jing Wu guang Yin Fan‑zhen Jiao Zhong‑zhen Yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

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The tangential k-Cauchy-Fueter type operator and Penrose type integral formula on the generalized complex Heisenberg group

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 181-190页

作者： REN guang-zhen SHI Yun kang Qian-qian Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023China Department of Mathematics Zhejiang University of Science and TechnologyHangzhou 310023China

The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,*** this paper,we introduce a Lie group that the Heisenberg group can be imbedded into and call it generalized complex *** investigate quaternionic analysis on the generalized complex *** also give the Penrose integral formula for k-CF functions and construct the tangential k-Cauchy-Fueter complex.

关键词： the generalized complex Heisenberg group the tangential k-Cauchy-Fueter type operator Penrose-type integral formula

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《沧浪诗话》“正法眼”说的诗学意义——兼论“法眼”与“诗眼”

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三峡大学学报（人文社会科学版） 2025年第1期47卷 7-12页

作者：康光磊山西警察学院基础部山西太原030401

在《沧浪诗话》中,“正法眼”及相近表述所蕴含的诗学主张构成了严羽独特的“正法眼”说,它将难以琢磨、言说和触摸的最高诗道以禅喻的方式揭示出来,丰富了中国传统诗学话语体系,提升了古典诗学对于诗歌难言之妙的阐释力,在诗学史上有... 详细信息

在《沧浪诗话》中,“正法眼”及相近表述所蕴含的诗学主张构成了严羽独特的“正法眼”说,它将难以琢磨、言说和触摸的最高诗道以禅喻的方式揭示出来,丰富了中国传统诗学话语体系,提升了古典诗学对于诗歌难言之妙的阐释力,在诗学史上有着不容忽视的意义。通过厘定“正法眼”说相关术语的内涵,阐释“正法眼”说与严羽“诗识观”“妙悟说”等诗学主张有机融合的内在理路,进而提出“正法眼”说是逻辑自洽、内证严密的完整体系。通过“法眼”与“诗眼”的辨析,指出严羽既重视“诗中之眼”的局部锤炼,更重视“诗家之眼”的整体观照,从而彰显“正法眼”说在严羽“以禅喻诗”体系中独特的诗学意义。

关键词： “正法眼”说《沧浪诗话》诗学价值法眼诗眼

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Influence of coupled characteristics on the internally-staged combustor under low-power operation

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航空动力学报 2017年第1期32卷 42-52页

作者： kang Yao LIN Yu-zhen Hunan Aviation Powerplant Research Institute Aero Engine(Group)Corporation of China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeijing University of Aeronautics and Astronautics

An ultra-low emissions combustor,namely low emission stirred swirl(LESS)combustor was studied,based on a scheme of internally-staged/lean premixed and prevaporized(LPP)*** LESS combustor consists of central pilot stage and outer surrounded coaxially main stage,between which there exists aphysical isolation,namely the step *** existence of step height delayed the pilot and main jets *** and numerical studies were carried out to investigate the influence of the step height on the combustion performance.A single dome rectangular combustor was utilized to conduct the lean lightoff and blowout experiments,and pollutant emission *** experimental results showed that with the increase of step height by 38%,the lean lightoff and blowout fuel air ratio decreased by 57.4% and 37.5%,the NOx emission increased by 35.1%,and the combustion efficiency increased by 1.78%;while the CO,unburned hydrocarbons(UHC)emissions ***,the total pressure loss was kept nearly ***-reacting and reacting flow fields were numerically investigated to analyze the coupled characteristics of pilot and main jets with different step heights.A comparison of flow characteristics,spray structure,and combustion component as well as temperature field with different step heights was *** numerical results showed that the increase of the step height shifted the peak velocity *** enlargement of the primary recirculation zone(PRZ)resulted in the increase of the combustion efficiency and NOx emission,while the CO,UHC emissions decreeased.

关键词：航空动力编辑研究工作

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Evolutions of CHCN abundance in molecular clumps

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Research in Astronomy and Astrophysics 2021年第8期21卷 245-252页

作者： zhen-zhen He guang-Xing Li Chao Zhang Department of Astronomy Yunnan UniversityKunming 650091China South-Western Institute For Astronomy Research Yunnan UniversityKunming 650091China

To investigate the effects of massive star evolution on surrounding molecules,we select nine massive clumps previously observed with the Atacama Pathfinder Experiment(APEX) telescope and the Submillimeter Array(SMA) *** on the observations of APEX,we obtain luminosity to mass ratios Lclump/Mclump that range from 10 to 154 L_(⊙)/M_(⊙),where some of them embedded ultra compact(UC) H Ⅱ *** the SMA,CH3CN(12K-11K) transitions were observed toward nine massive starforming *** derive the CH3CN rotational temperature and column density using the XCLASS program,and calculate its fractional *** find that CH3CN temperature seems to increase with the increase of Lclump/Mclump when the ratio is between 10 to 40 L_(⊙)/M_(⊙),then decrease when L_(clump)/M_(clump)≥ 40 L_(⊙)/M_(⊙).Assuming that the CH3CN gas is heated by radiation from the central star,the effective distance of CH3CN relative to the central star is *** distance ranges from - 0.003 to - 0.083 pc,which accounts for - 1/100 to - 1/1000 of clump *** effective distance increases slightly as Lclump/Mclump increases(Reff-(L_(clump)/M_(clump))0.5±0.2).Overall,the CH3 CN abundance is found to decrease as the clumps evolve,e.g.,XCH3CN -(L_(clump)/M_(clump))-1.0±*** steady decline of CH3CN abundance as the clumps evolution can be interpreted as a result of photodissociation.

关键词： line:identification stars:evolution stars:formation ISM:molecules submillimeter:ISM

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Regulation of intestinal stem cell fate specification

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Science China(Life Sciences) 2015年第6期58卷 570-578页

作者： QI zhen CHEN Ye-guang State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua-Peking Center for Life Sciences School of Life SciencesTsinghua University

The remarkable ability of rapid self-renewal makes the intestinal epithelium an ideal model for the study of adult stem cells. The intestinal epithelium is organized into villus and crypt, and a group of intestinal stem cells located at the base of crypt are responsible for this constant self-renewal throughout the life. Identification of the intestinal stem cell marker Lgr5, isolation and in vitro culture of Lgr5+ intestinal stem cells and the use of transgenic mouse models have significantly facilitated the studies of intestinal stem cell homeostasis and differentiation, therefore greatly expanding our knowledge of the regulatory mechanisms underlying the intestinal stem cell fate determination. In this review, we summarize the current understanding of how signals of Wnt, BMP, Notch and EGF in the stem cell niche modulate the intestinal stem cell fate.

关键词： intestinal stem cells Wnt BMP Notch EGF fate specification

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