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Statistical Research on Megahertz-peaked Spectra Pulsars

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Research in Astronomy and Astrophysics 2025年第1期25卷 116-134页

作者： Hong-Bing Cai Li Chen Shi-Dang Li Kai Wang Hang Liu JSNU SPBPU Institute of engineering & SINO RUSSIAN Institute Jiangsu Normal University school of physics and Electronic engineering Jiangsu Normal University

Megahertz-peaked spectra(MPS) pulsars are referred as cases whose radio spectra turn over around 100 MHz. We identified 53 MPS pulsars based on the spectral data from the literature, and statistically analyzed the spatial location distribution, the magnetic field-period distribution, peak frequencies, spectral indices, and dispersion measures of these MPS pulsars. We found that there is a strong positive correlation between the dispersion measures and the peak frequencies of MPS pulsars, and negative correlations of the dispersion measures with spectral indices and the ages are also found. Such correlations suggest that the interstellar medium is an important factor that affects observational properties of MPS pulsars.

关键词： (stars:) pulsars: general ISM: general radio continuum: general

Phonon-mediated superconductivity in orthorhombic XS(X=Nb,Ta or W)

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Chinese physics B 2025年第2期34卷 419-423页

作者： Guo-Hua Liu Kai-Yue Jiang Yi Wan Shu-Xiang Qiao Jin-Han Tan Na Jiao Ping Zhang Hong-Yan Lu school of physics and Physical engineering Qufu Normal UniversityQufu 273165China Institute of Applied physics and Computational Mathematics Beijing 100088China

The unique three-dimensional orthorhombic NbS(o-NbS)compound synthesized in 1969 has recently been experimentally confirmed to be a superconductor[***.B 108174517(2023)].However,there is currently no theoretical research on its superconducting *** this work,we investigate the superconducting properties of o-Nb S from first-principles *** on the Eliashberg equation,it is found that the superconductivity mainly originates from the coupling between the electrons of Nb-4d orbitals and the vibrations of Nb atoms in the low-frequency region and those of S atoms in the high-frequency region.A superconducting transition temperature(T_c)of 10.7 K is obtained,which is close to the experimental value and higher than most transition metal chalcogenides(TMCs).The calculated thermodynamic properties in the superconducting state,such as specific heat,energy gap,isotope coefficient,etc.,also indicate that o-NbS is a conventional phonon-mediated *** results are consistent with recent experimental reports and provide a good understanding of the superconducting mechanism of o-Nb ***,the TMCs of o-TaS and o-WS are also investigated;these belong to the same and neighboring groups of Nb,and we find that o-TaS and o-WS are also phonon-mediated superconductors with T_c of 8.9 K and 7.2 K,respectively.

关键词： first-principles calculations phonon-mediated superconductivity orthorhombic transition metal chalcogenides

On load dependence of detachment rate of kinesin motor

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Chinese physics B 2025年第1期34卷 498-505页

作者： Xiao-Xuan Shi Yao Wang Yu-Ru Liu Ping Xie school of Pharmaceutical engineering Chongqing Chemical Industry Vocational CollegeChongqing 401220China Laboratory of Soft Matter physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Kinesin is an archetypal microtubule-based molecular motor that can generate force to transport cargo in cells. The load dependence of the detachment rate is an important factor of the kinesin motor, the determination of which is critically related to the chemomechanical coupling mechanism of the motor. Here, we use three models for the load dependence of the detachment rate of the kinesin motor to study theoretically and numerically the maximal force generated and microtubuleattachment duration of the motor. By comparing the theoretical and numerical results with the available experimental data,we show that only one model can explain well the available experimental data, indicating that only this model can be applicable to the kinesin motor.

关键词： kinesin detachment rate generated force chemomechanical coupling mechanism optical trapping

Bound state noise-like pulses generation from composite filtering effects

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Optoelectronics Letters 2025年第3期21卷 142-148页

作者： CHANG Qingyu ZHANG Caishi College of physics & Optoelectronic engineering Jinan University Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology School of Physics and Optoelectronic EngineeringMacau University of Science and Technology school of Innovation engineering Macau University of Science and Technology

This paper demonstrated the generation of multi-wavelength bound state noise-like pulse (BNLP) in a dispersion-managed composite-filtered fiber laser consisting of nonlinear polarization rotation (NPR) and *** the case of BNLP,the generation is caused by the interaction between two noise-like pulses (NLPs) induced by the comb-filtering effect,and bound state level can be artificially controlled in the *** work provides a new method for generating low-coherence pulses and establishes a research idea for the study of the comb-filtering effects.

关键词： A

Magnetically-responsive phase change thermal storage materials:Mechanisms,advances,and beyond

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Journal of Energy Chemistry 2025年第2期101卷 485-510页

作者： Yan Gao Yang Li Jinjie Lin Panpan Liu Xiao Chen Ge Wang Beijing Advanced Innovation Center for Materials Genome engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing school of physics and Astronomy Beijing Normal University Shunde Graduate school University of Science and Technology Beijing

Rapid advances in thermal management technology and the increasing need for multi-energy conversion have placed stringent energy efficiency requirements on next-generation shape-stable composite phase change materials(PCMs).Magnetically-responsive phase change thermal storage materials are considered an emerging concept for energy storage systems,enabling PCMs to perform unprecedented functions(such as green energy utilization,magnetic thermotherapy,drug release,etc.).The combination of multifunctional magnetic nanomaterials and PCMs is a milestone in the creation of advanced multifunctional composite ***,a timely and comprehensive review of composite PCMs based on magnetic nanoparticle modification is still ***,we furnish an exhaustive exposition elucidating the cutting-edge advancements in magnetically responsive composite *** delve deeply into the multifarious roles assumed by distinct nanoparticles within composite PCMs of varying dimensions,meticulously scrutinizing the intricate interplay between their architectures and thermophysical ***,we prognosticate future research trajectories,delineate alternative stratagems,and illuminate prospective *** review is intended to stimulate broader academic interest in interdisciplinary fields and provide valuable insights into the development of next-generation magnetically-responsive composite PCMs.

关键词： Magnetic nanoparticles Magnetic-thermal conversion Phase change materials Response mechanism Thermal energy storage

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang Jia-Jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Structural,optical,and photocatalytic properties of Bi_(1-x)RE_(x)FeO_(3)(RE=La,Ce,Pr,Nd,Sm;x=0,0.05,0.1) thin films

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Journal of Rare Earths 2025年第1期43卷 81-88,I0004页

作者： Ahmad Gholizadeh Sakineh Hosseini school of physics Damghan UniversityDamghanIran

Bismuth ferrite perovskite materials have recently attracted great attention because of their unique *** this study,Bi_(1-x)RE_(x)FeO_(3)(RE=La,Ce,Pr,Nd,Sm;x=0,0.05,0.1)thin films were deposited on glass substrates via low-temperature sol-gel assisted spin coating *** is found that in the presence of light rare-earth ions as the substitutions,the structural,morphological,and optical properties of the thin films are changed in the prepared thin *** find that the thin films have rhombohedral structures,and from field emission scanning electron microscopy(FESEM)images,it is observed that the substitution of light rare-earth ions for Bi^(3+)affects the surface morphology and grain size of the BiFeO_(3)(BFO)thin ***,the optical properties of prepared films were investigated via UV-visible *** all samples,the bandgap energy values are between 1.22 and 1.65 ***,the refractive index and extinction coefficient of samples are about 1.14-1.41 and 0.1-0.6,*** properties of the samples were investigated by measuring the degradation of methylene blue(MB)dye under irradiation of *** find that the light rare-earth substituted BFO thin films have better photocatalytic activity compared to pure BiFeO_(3) thin film,the reason can be described as the band gap varied between 1.20 and 1.65 eV for different rare earth ions which directly influences the photocatalytic properties of the investigated *** is observed that the prepared thin films can remove between 37.18%and 69.14%of dye after 180 min of *** study confirms that prepared thin films are a suitable candidate for photocatalytic applications.

关键词： Bismuth ferrite thin film Sol-gel spin coating Substitution effect Rareearth ions Photocatalytic activity

Recent development in electrode design for wide-temperature supercapacitors

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Science China Chemistry 2025年第1期68卷 96-117页

作者： Jianhong Liu Qiang Zhou Yuxiao Lin Xinsheng Zhao Guangmin Zhou Xiaoxiao Li school of physics and Electronic engineering Jiangsu Normal UniversityXuzhou 221116China Tsinghua-Berkeley Shenzhen Institute&Tsinghua Shenzhen International Graduate school Tsinghua UniversityShenzhen 518055China

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(SCs).The active electrode is one of the most important parts of SC,which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature *** with the SC electrodes aimed for room-temperature application,the SC electrodes for operating at wide-temperature scene often face greater *** this review,the main challenges of SC electrodes under various temperature conditions,including low,high and cross-fade temperatures,are *** relevant performance decay and failure mechanisms of wide-temperature SC electrodes are *** addition,this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active ***,the future directions for exploring reliable wide-temperature SCs are also proposed.

关键词： supercapacitor wide-temperature electrode design active materials

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(physics,Mechanics & Astronomy) 2025年第1期68卷 136-143页

作者： Di-Chao Chen Xie Liu Changqing Xu Da-Jian Wu Ying Cheng Xiao-Jun Liu school of physics and Technology Nanjing Normal UniversityNanjing 210023China Key Laboratory of Modern Acoustics School of PhysicsNanjing UniversityNanjing 210093China

Vortex transmutation utilizes a periodic system,which not only enables the alteration of the topological charge(TC)of unstable input vortices but also facilitates their transformation into stable *** approach is crucial for investigating the characteristics of vortices in various wave ***,we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES).The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete *** results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures,enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure