检索结果-南通市图书馆

Spherical-like spectra for the description of the normal states of ^(108-120)Cd in the SU3-IBM and the Q2_(1)^(+) anomaly

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese physics C 2025年第1期49卷 255-268页

作者： Tao Wang Xin Chen Yu Zhang College of physics Tonghua Normal UniversityTonghua 134000China department of physics Liaoning Normal UniversityDalian 116029China

The Cd puzzle implies that the phonon excitation of a spherical nucleus should be questioned and *** understand the newly and experimentally discovered spherical-like γ-soft mode,the SU3-IBM was recently proposed In this study,the evolutions ofthe normal states in ^(108-120)Cd are investigated and compared with the experimental *** better explain the nearly zero B(E2)values between the O_(2)^(+) and 2_(1)^(+) states,SU(3)higherorder interactions except for the SU(3)second-order and third-order Casimir operators are also considered in *** find that the results of theoretical fitting and experimental data agree well with simple parameter selection,and the spherical-like spectra truly *** deficiency may arise from the lack of configuration *** realistic spectra characteristicsof thespherical-like spectrare found for ^(118,120)Cd,and the electricquadrupole moments of the 2_(1)^(+) state are *** Q2_(1)^(+)anomaly in ^(108-116)Cd is also discussed.

关键词： SU3-IBM Cd puzzle ^(108-120)Cd spherical-like spectrum Q2_(1)^(+)anomaly

Solving the relativistic Hartree-Bogoliubov equation with the finite-difference method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese physics C 2025年第1期49卷 245-254页

作者： Yiran Wang Xiaojie Cao Jinniu Hu Ying Zhang department of physics Faculty of ScienceTianjin UniversityTianjin 300354China School of physics Nankai UniversityTianjin 300071China

The relativistic Hartree-Bogoliubov(RHB)theory is a powerful tool for describing exotic nuclei near drip *** key technique is to solve the RHB equation in the coordinate space to obtain the quasi-particle *** this paper,we solve the RHB equation with the Woods-Saxon-type mean-field and Delta-type pairing-field potentials by using the finite-difference method(FDM).We inevitably obtain spurious states when using the common symmetric central difference formula(CDF)to construct the Hamiltonian matrix,which is similar to the problem resulting from solving the Dirac equation with the same *** problem is solved by using the asymmetric difference formula(ADF).In addition,we show that a large enough box is necessary to describe the continuum quasi-particle *** canonical states obtained by diagonalizing the density matrix constructed by the quasi-particle states are not particularly sensitive to the box *** of the asymptotic wave functions can be improved by applying the ADF in the FDM compared to the shooting method with the same box boundary condition.

关键词： relativistic Hartree-Bogoliubov equation spurious state finite-difference method

Pulsar scintillation reveals the Gum Nebula as a scattering screen

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(physics,Mechanics & Astronomy) 2025年第3期68卷 192-192页

作者： Dan Stinebring department of physics and Astronomy Oberlin CollegeOberlinOH44074USA

Since soon after the discovery of radio pulsars in 1968,their scintillation due to multi-path scattering in the interstellar medium(ISM)emerged as a useful tool in studying the *** example,a recent study with the Five-hundred-metre Aperture Spherical Telescope(FAST)by Yao et al.[1]has demonstrated scattering due to a 100K-year-old supernova remnant(the Monogem Ring)as well as close alignment of the pulsar spin axis and its velocity vector.

关键词： scattering supernova pulsar

维普期刊数据库

同方期刊数据库

Systematic study of cross section for proton-induced reactions on neodymium up to 65 MeV using TALYS-1.96 code

在线全文

学校读者我要写书评

暂无评论

Chinese physics C 2025年第1期49卷 195-206页

作者： A.Saha department of physics ICFAI University TripuraKamalghatTripura 799210India

A systematic study was conducted on the theoretical estimation of the nuclear cross sections of charged particle induced reactions on rare earth *** production cross sections of the ^(150,149,148,146,144,143,141)Pm and ^(149,147)Nd nuclei were calculated theoretically via proton induced reactions on neodymium using TALYS(version 1.96)code in the default mode,with different combinations of nuclear models as well as adjusted nuclear model parameters from the reaction threshold up to a proton energy of 65 *** theoretically computed results were compared with the experimental results taken from the EXFOR database and literature reported by various research ***,the effects of various level density models,preequilibrium models,optical model potentials,and gamma strength functions on the cross section calculation were *** theoretical analysis will help elucidate the theory of nuclear reaction models and improve the evaluated nuclear data libraries.

关键词： nuclear reaction cross section TALYS code level density models compound nucleus mechanism

Axial coordinated iron-nitrogen-carbon as efficient electrocatalysts for hydrogen evolution and oxygen redox reactions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2025年第1期36卷 637-642页

作者： Yanan Zhou Li Sheng Lanlan Chen Wenhua Zhang Jinlong Yang School of Material Science and Chemical Engineering Institute of Mass SpectrometryNingbo UniversityNingbo 315211China department of Chemical physics University of Science and Technology of ChinaHefei 230026China department of Material Science and Engineering University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy Conversion and Synergetic Innovation Centre of Quantum Information and Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Designing highly active electrocatalysts for the hydrogen evolution reaction(HER)and oxygen evolution and reduction reactions(OER and ORR)is pivotal to renewable energy ***,based on density functional theory(DFT)calculations,we systematically investigate the catalytic activity of iron-nitrogen-carbon based covalent organic frameworks(COF)monolayers with axially coordinated ligands(denotes as Fe N_(4)-X@COF,X refers to axial ligand,X=-SCN,-I,-H,-SH,-NO_(2),-Br,-ClO,-Cl,-HCO_(3),-NO,-ClO_(2),-OH,-CN and-F).The calculated results demonstrate that all the catalysts possess good thermodynamic and electrochemical *** different ligands axially ligated to the Fe active center could induce changes in the charge of the Fe center,which further regulates the interaction strength between intermediates and catalysts that governs the catalytic ***,FeN_(4)-SH@COF and Fe N_(4)-OH@COF are efficient bifunctional catalysts for HER and OER,FeN_(4)-OH@COF and FeN_(4)-I@COF are promising bifunctional catalysts for OER and *** findings not only reveal promising bifunctional HER/OER and OER/ORR catalysts but also provide theoretical guidance for designing optimum ironnitrogen-carbon based catalysts.

关键词： Axial coordinated ligands DFT calculation Hydrogen evolution reaction Oxygen evolution reaction Oxygen reduction reaction

维普期刊数据库

Revealing Light-Induced Charge Density Wave Melting and Carrier Redistribution in 1T-TiSe_2

在线全文

学校读者我要写书评

暂无评论

Chinese physics Letters 2025年第1期42卷 123-133页

作者： Wanying Chen Haoyuan Zhong Changhua Bao Fei Wang Xuanxi Cai Chenxia Yun Hao Teng Zhiyi Wei Shuyun Zhou State Key Laboratory of Low-Dimensional Quantum physics and department of physics Tsinghua UniversityBeijing 100084China Beijing National Laboratory for Condensed Matter physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Frontier Science Center for Quantum Information Beijing 100084China

Capturing ultrafast dynamics over a large momentum space is critical for revealing the relationship between the electronic and structural modulations in quantum ***,by performing time-and angle-resolved photoemission spectroscopy measurements at the Synergetic Extreme Condition User Facility(SECUF)equipped with an extreme ultraviolet light source,we reveal the ultrafast dynamics of a charge-density wave(CDW)material,1T-TiSe_(2),upon ***-induced CDW melting is revealed from two aspects:gap closing of the CDW at the Brillouin zone(BZ)center and weakening of the CDW folded band at the BZ *** comparing the transient electronic structure and spectral weight over a large momentum space,we further reveal the carrier redistribution involving the excitation of electrons from theГpoint to the M *** study provides a comprehensive picture of the physics and ultrafast dynamics of a CDW material across the entire BZ.

关键词： momentum equipped distribution

维普期刊数据库

Comprehensive Analysis of the Ionospheric Response to the 2015 Geomagnetic Storms over Different Station

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Climate Sciences 2025年第1期15卷 175-186页

作者： Aidashisha Bareh Bornali Chetia physics department The Assam Royal Global University Guwahati India

The fundamental problem of ionospheric physics lies in understanding and modeling the ionosphere’s dependence on solar activity. This challenge encompasses such as Variables across Solar Cycles, Response to Solar Flares and CMEs, Daily and Seasonal Effects, Spatial Variability and long term prediction models. This dependency on solar activity helps provide information that is fundamental to comprehend the changes in the ionosphere and its processes. In this work, the ionospheric critical frequency foF2 and electron density are applied to characterize large-scale ionosphere responses during the 2015 geomagnetic storm. Using data from the International Reference Ionosphere (IRI-2016 model), an empirical standard model of the Ionosphere, this work tries to construct a correspondence between the solar activity and the change in the Ionosphere’s characteristics across three different stations at different altitudes. It has been observed that the electron density decreases from (1.098E + 12 to 7.844E + 11) for low latitude, (6.358E + 11 to 3.650E + 11.) for mid latitude and (4.765E + 11 to 2.740E + 11) for high latitude on the day of the solar event. A similar decrease in foF2 by 40% - 70% can also be seen for the three different stations on the geomagnetic storm day.

关键词： Electron Density foF2 Geomagnetic Storm IRI 2016

Phase saddle point transformation-enabled mode-adaptive detection of acoustic orbital angular momentum with high efficiency and low crosstalk

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(physics,Mechanics & Astronomy) 2025年

作者： Kai Wu Yang Tan Jingjing Liu Bin Liang Jianchun Cheng Collaborative Innovation Center of Advanced Microstructures and Key Laboratory of Modern Acoustics MOE Institute of AcousticsDepartment of Physics Nanjing University

Acoustic orbital angular momentum (OAM) provides an infinite set of orthogonal bases in Hilbert space and significantly boosts the link capacity and data transmission rate. High-capacity and low-crosstalk OAM detection within compact physical space is highly desired to effectively harness this spatial dimension of sound wave, but the existing mechanisms generally either operate only for finite OAMs with predetermined mode orders or rely on complicated active devices. Here, we propose a phase saddle point (PSP) transformation mechanism for distinguishing and demultiplexing acoustic OAM modes in a passive, mode-adaptive,high-efficiency, and high-accuracy paradigm. The phase mask characterized by a PSP in the specific area is created through the single-pass log-polar transformation without prior information of incident modes, whose interaction with incident vortex beams of different OAM modes will yield the translation of the stationary phase point and thereby generate the corresponding focused line spots at distinct lateral positions. We theoretically elucidate the mode-adaptive response of PSP transformation by deriving the quantitative relationship between the OAM order and line spot offset. This mode adaptability enables our mechanism to detect OAM of arbitrary mode orders and mode numbers with the inter-mode crosstalk being effectively suppressed, beyond attainable with the existing methods. The effectiveness of our proposed mechanism is validated by demonstrating several distinct examples of single-mode OAM sorting and multi-mode synthesized vortex beam demultiplexing. We anticipate this modeadaptive methodology, designed for compact dimensions and featuring with low crosstalk and uniform efficiency, will find important applications in OAM information processing.

关键词：

Stability on a 3D incompressible Oldroyd-B model with mixed partial dissipation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Mathematics 2025年

作者： Hongxia Lin Jiahong Wu Nicki Boardman Geomathematics Key Laboratory of Sichuan Province College of Mathematics and PhysicsChengdu University of Technology department of Mathematics University of Notre Dame (USA) department of Mathematics Oklahoma State University

The Oldroyd-B equations model viscoelastic fluids. Attention here is focused on a three-dimensional（3D） Oldroyd-B system with mixed dissipation, horizontal velocity dissipation and vertical diffusion for the nonNewtonian stress tensor τ. The equation of τ has no damping, a setup relevant to high Weissenberg viscoelastic flows. In this paper, we solve the small-data global well-posedness and the stability problem in the Sobolev space H2（R3）. The lack of the horizontal dissipation or damping in the equation of τ makes the problem almost impossible. This paper discovers that the coupling and interaction of the fluid velocity u and τ generates extra smoothing and stabilization. Mathematically, u and P▽·τ satisfy a system of wave equations, which provides the desired enhanced dissipation. Here, P = I-▽△-1▽· denotes the projection onto divergence-free vector *** addition, time-weighted energy functionals are introduced to control low-regularity terms. The second major result of this paper establishes optimal decay rates by making use of the aforementioned enhanced dissipation and the integral representation.

关键词：