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Nuclear Science and Techniques 2024年第6期35卷 114-119页

作者： Chun-Wang Ma Yi-Jie Duan ya-fei guo Chun-Yuan Qiao Yu-Ting Wang Jie Pu Kai-Xuan Cheng Hui-Ling Wei College of Physics Henan Normal UniversityXinxiang 453007China Institute of Nuclear Science and Technology Henan Academy of SciencesZhengzhou 450015China

Neutron-skin thickness is a key parameter for a neutron-rich nucleus;however,it is difficult to *** the framework of the Lanzhou Quantum Molecular Dynamics(LQMD)model,a possible probe for the neutron-skin thickness(δ_(np))of neutron-rich ^(48)Ca was studied in the 140A MeV ^(48)Ca+^(9)Be projectile fragmentation reaction based on the parallel momentum distribution(p∥)of the residual fragments.A Fermi-type density distribution was employed to initiate the neutron density distributions in the LQMD simulations.A combined Gaussian function with different width parameters for the left side(Γ_(L))and the right side(Γ_(R))in the distribution was used to describe the p∥of the residual *** neutron-rich sulfur isotopes as examples,Γ_(L) shows a sensitive correlation withδ_(np) of ^(48)Ca,and is proposed as a probe for determining the neutron skin thickness of the projectile nucleus.

关键词： Neutron-skin thickness Projectile fragmentation Parallel momentum distribution Neutron-rich nucleus Quantum molecular dynamics model

Non-frozen process of heavy-ion fusion reactions at deep sub-barrier energies

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Nuclear Science and Techniques 2022年第10期33卷 117-125页

作者： Kai-Xuan Cheng Jie Pu Yu-Ting Wang ya-fei guo Chun-Wang Ma School of Physics Henan Normal UniversityXinxiang 453007China

The hindrance in heavy-ion fusion reactions a deep sub-barrier energies is investigated using the double folding model with a hybrid method between the frozen and adiabatic density *** this method,the density distributions of the projectile and the target depend closely on the distance between *** the distance decreased,the half-density radii of the colliding nucle gradually increased to the half-density radius of the compound *** total potential based on this non-frozen approximation generates a slightly shallower pocket and becomes more attractive inside the pocket compared to that obtained from the frozen approximation.A damping factor was used to simulate the decline of the coupled channel effects owing to the density rearrangement of the two colliding *** calculated fusion cross-sections and astrophysical S factors at the deep sub-barrier energies are both in good agreement with the experimental data for the medium-heavyNi+Ni and medium-lightMg+Si mass *** addition,it was concluded that the apparent maximum of the S factors most likely appears in fusion systems with strong coupling effects.

关键词： Adiabatic approximation Double folding model Fusion hindrance

Multiple-models predictions for drip line nuclides in projectile fragmentation of^(40,48)Ca,^(58,64)Ni,and^(78,86)Kr at 140 MeV/u

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Nuclear Science and Techniques 2022年第12期33卷 49-58页

作者： Xiao-Bao Wei Hui-Ling Wei Yu-Ting Wang Jie Pu Kai-Xuan Cheng ya-fei guo Chun-Wang Ma College of Physics Henan Normal UniversityXinxiang 453007China

Modern rare isotope beam(RIB)factories will significantly enhance the production of extremely rare isotopes(ERI)at or near drip *** one of the most important methods employed in RIB factories,the production of ERIs in projectile fragmentation reactions should be theoretically improved to provide better guidance for experimental *** cross-sections of ERIs produced in 140 MeV/u^(78,86)Kr/^(58,64)Ni/^(40,48)Ca+9Be projectile fragmentation reactions were predicted using the newly proposed models[i.e.,Bayesian neural network(BNN),BNN+FRACS,and FRACS,see ***.C,46:074104(2022)]and the frequently used EPAX3 *** a minimum cross-section of 1015 mb,the possibilities of ERIs discovery in a new facility for rare isotope beams(FRIB)are discussed.

关键词： Bayesian neural network(BNN) FRACS Drip line Extremely rare isotope Projectile fragmentation

SPAGINS:semiempirical parameterization for fragments in gamma-induced nuclear spallation

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Nuclear Science and Techniques 2023年第12期34卷 112-122页

作者： Hui‑Ling Wei Meng‑Die Zhou Pu Jiao Yu‑Ting Wang Jie Pu Kai‑Xuan Cheng ya‑fei guo Chun‑Yuan Qiao Gong‑Tao Fan Hong‑Wei Wang Chun‑Wang Ma Institute of Particle and Nuclear Physics College of PhysicsHenan Normal UniversityXinxiang 453007China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China Institute of Nuclear Science and Technology Henan Academy of ScienceZhengzhou 450046China

From the empirical phenomena of fragment distributions in nuclear spallation reactions,semiempirical formulas named SPAGINS were constructed to predict fragment cross-sections in high-energyγ-induced nuclear spallation reactions(PNSR).In constructing the SPAGINS formulas,theoretical models,including the TALYS toolkit,SPACS,and Rudstam formulas,were employed to study the general phenomenon of fragment distributions in PNSR with incident energies ranging from 100 to 1000 *** the primary characteristics of PNSR,the SPAGINS formulas modify the EPAX and SPACS formulas and efficiently reproduce the measured *** SPAGINS formulas provide a new and effective tool for predicting fragment production in PNSR.

关键词： High-energy gamma-rays Spallation reaction Fragment cross-section Empirical formula EPAX SPACS TALYS

Nuclear dynamics in multinucleon transfer reactions near Coulomb barrier energies

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Nuclear Science and Techniques 2018年第12期29卷 128-133页

作者： Peng-Hui Chen fei Niu ya-fei guo Zhao-Qing Feng Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 China University of Chinese Academy of Sciences Beijing 100190China South China University of Technology Guangzhou 510641China

The mechanism of multinucleon transfer reactions has been investigated within the dinuclear system model, in which the sequential nucleon transfer is described by solving a set of microscopically derived master equations. The transfer dynamics in the reaction of^(136)Xe+^(208)Pb near Coulomb barrier energies is thoroughly analyzed. It is found that the total kinetic energies of primary fragments are dissipated from the relative motion energy of two touching nuclei and exhibit a symmetric distribution along the fragment mass. The angular distribution of the projectile-like fragments moves forward with increasing beam energy. However, the target-like fragments exhibit an opposite trend. The shell effect is pronounced due to the fragment yields in multinucleon transfer reactions.

关键词：原子动力学转移反应精力库仑相对运动显微镜子转移原子核

Homoclinic Solutions for a Class of Perturbed Fractional Hamiltonian Systems with Subquadratic Conditions

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1177-1196页

作者： Ying LUO fei guo yan LIU School of Mathematics Tianjin UniversityTianjin 300354P.R.China Tianjin Key Laboratory of Brain-Inspired Intelligence Technology Tianjin300354P.R.China

In this paper,we consider the following perturbed fractional Hamiltonian systems{tD_(∞)^(α)(_(-∞)D_(t)^(α)u(t))+L(t)u(t)=■_(u)W(t,u(t))+■(u)G(t,u(t)),t∈R,u∈H^(α)(R,R^(N)),whereα∈(1/2,1],L∈C(R,R^(N×N))is symmetric and not necessarily required to be positive definite,W∈C1(R×R^(N,R))is locally subquadratic and locally even near the origin,and perturbed term G∈C1(R×R^(N,R))maybe has no parity in *** the perturbed method improved by the authors,a sequence of nontrivial homo clinic solutions is obtained,which generalizes previous results.

关键词： Perturbed fractional Hamiltonian systems subquadratic condition perturbed method homoclinic solutions multiplicity

Impacts of pancreatic exocrine insufficiency on gut microbiota

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 271-279页

作者： Yulin guo Feng CAO fei LI Department of General Surgery Xuanwu Hospital of Capital Medical UniversityBeijing 100053China Acute Pancreatitis Clinical Center of Capital Medical University Beijing 100053China

Pancreatic exocrine insufficiency(PEI)can be induced by various kinds of diseases,including chronic pancreatitis,acute pancreatitis,and *** main pathogenetic mechanism of PEI involves the decline of trypsin synthesis,disorder of pancreatic fluid flow,and imbalance of secretion *** studies have shown that PEI could induce gut bacterial overgrowth and dysbiosis,with the abundance of Lactobacillus and Bifidobacterium increasing the most,which could be partially reversed by pancreatic enzyme replacement *** studies have also confirmed the association between PEI and the dysbiosis of gut *** exocrine secretions and changes in duodenal p H as well as bile salt malabsorption brought about by PEI may affect and shape the abundance and composition of gut *** turn,the gut microbiota may impact the pancreatic exocrine acinus through potential bidirectional *** forward,more and higher-quality studies are needed that focus on the mechanism underlying the impact of PEI on the gut microbiota.

关键词： Pancreatic exocrine insufficiency Gut microbiota Gut microbiome Pancreatic enzyme replacement therapy

Weighted Composition Operators That Preserve Frames On Weighted Hardy Spaces

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1645-1654页

作者： ya Li Dong Rui Liu guo Xiang Lu School of Mathematical Sciences and LPMC Nankai UniversityTianjin300071P.R.China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan430073P.R.China

In this paper, we characterize weighted composition operators that preserve frames on the weighted Hardy spaces in the unit disk. In particular, we obtain the symbol properties of the bounded invertible weighted composition operators. Moreover, we establish the equivalence between bounded invertible operators and frame-preserving operators. Furthermore, we show that weighted composition operator preserves frames if and only if it preserves the Riesz bases property. Additionally,we investigate the weighted composition operators that preserve tight or normalized tight frames on the Dirichlet space.

关键词： Weighted composition operators Weighted Hardy spaces frames invertible

A novel strategy for in situ maskless synthesis of biochips:Self-driving micro-fluid porous type printing (SMPTP)

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Chinese Chemical Letters 2007年第1期18卷 111-114页

作者： Nong Yue He ya fei guo Song Li Jian-Xin Tang State Key Laboratory of Bioelectronics Southeast University Nanjing 210096 China Key Laboratory of Green-Packaging and Application of Bionanotechnology of Hunan Province Zhuzhou Institute of Technology Zhuzhou 412008 China

A novel maskless technique, self-driving micro-fluid porous type printing （SMPTP）, was reported to in situ synthesize oligonucleotide arrays on glass slide, which has the merits of low cost, high quality and simple craft. In SMPTP for fabricating gene- chips, porous fiber tubes with a number of nanometric or micron channels functioned as ＂active letters＂ and were assembled in designed patterns, which are identical to the distribution of monomers in each layer of the array, and four patterns were needed for each layer. By means of capillarity, the synthesis solution was automatically taken into porous tubes assembled in a printing plate and reached the surface. An oligonucleotide array of 160 features with four different 15-mer probes was in situ synthesized using this technique. The four specific oligonucleotide probes, including the matched and the mismatched by the fluorescent target sequence, gave obviously different hybridization fluorescent signals.

关键词： Typography Oligonucleotide In situ synthesis DNA microarrays Biochips

Teukolsky-like equations with various spins in spherically symmetric spacetime

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Chinese Physics C 2024年第8期48卷 213-223页

作者： ya guo Hiroaki Nakajima Wenbin Lin School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Mathematics and Physics University of South ChinaHengyang 421001China

We study wave equations with various spins on the background of a general spherically symmetric *** obtain the unified expression of the Teukolsky-like master equations and the corresponding radial equations with the general *** also discuss the gauge dependence in the gravitational-wave equations,which have appeared in previous studies.

关键词： gravitational wave effective one-body dynamics Teukolsky equation wave equations Klein-Gordon equation Weyl equation Maxwell equation