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激光与光电子学进展 2024年第5期61卷 397-403页

作者： Hao Lili Wang Zhen Tang Hongxia Zhang Xiaoyang Yang Qi Wang Qiang department of physics College of physics and Electronic EngineeringNortheast Petroleum UniversityDaqing 163318HeilongjiangChina department of physics College of Electrical EngineeringSuihua UniversitySuihua 152000HeilongjiangChina

We present a theoretical study of the one-dimensional modulational instability of a broad optical beam propagating in a biased photorefractive crystal with both linear and quadratic electro-optic effects(Kerr effect)under steadystate ***-dimensional modulational instability growth rates are obtained by treating the space-charge field equation globally and *** theoretical reasoning and numerical simulation show that both the global and local modulational instability gains are governed simultaneously by the strength and the polarity of external bias field and by the ratio of the intensity of the broad beam to that of the dark *** a strong bias field,the results obtained using these two methods are in good agreement in the low spatial frequency ***,the instability growth rate increases with the bias field,and the maximum instability growth occurs when ratio of light intensity to dark irradiance is 0.88.

关键词： nonlinear optics photorefractive effects spatial soliton modulational instability

Tuning structural,electrical,dielectric and magnetic properties of Mg-Cu-Co ferrites via dysprosium(Dy^(3+))doping

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Journal of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： Maria Akhtar M.S.Hasan Nasir Amin N.A.Morley Muhammad Imran Arshad department of physics Government College UniversityFaisalabad38000Pakistan department of physics The University of Lahore53700Pakistan department of Materials Science and engineering The University of SheffieldS13JDUK department of physics&Astronomy University College LondonUK

In current research work,Dy3+substituted Mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step interval of 0.01)soft ferrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared(FTIR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(VSM)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=*** non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from EDX *** DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 *** minimum dielectric loss at high frequency is found for sample x=*** coercivity(Hc)and saturation magnetization(Ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations confirm that dysprosium(x=0.03)doped MCC-soft ferrites may be applicable in transformer cores,microwave absorbance,and telecommunication devices.

关键词： Soft ferrites DC resistivity Dielectric loss Impedance Coercivity Rare earths

Cr-induced fusion reactions to synthesize superheavy elements

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Nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.Madhu H.C.Manjunatha N.Sowmya B.M.Rajesh L.Seenappa R.S.Susheela department of physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India department of physics Government First Grade CollegeSrinivasapurKarnataka 563135India department of physics Government First Grade CollegeDevanahallyKarnataka 562110India department of physics Government First Grade CollegeMulbagalKarnataka 563131India department of physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)Cr+^(243)Am,23.2 fb at 236 MeV for ^(54)Cr+^(247)Cm,95.6 fb at 240 MeV for ^(53)Cr+248Bk,and 1.33 fb at 242 MeV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability Survival probability Evaporation residue cross sections

Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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Science China(Technological Sciences) 2024年第5期67卷 1297-1316页

作者： CHEN Jie GUO RuiLong GUO HengYu college of physics and Electronic engineering Chongqing Normal UniversityChongqing 401331China department of Applied physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies

Reconstructing coherent dynamics of bound states induced by strong attosecond XUV pulses

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Chinese Optics Letters 2024年第2期22卷 56-63页

作者：贾利娟刘明清王新强徐龙闫培光姜维超傅立斌 Institute of Quantum Precision Measurement College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China department of physics Xiamen UniversityXiamen 361005China Graduate School of China Academy of engineering physics Beijing 100193China

We propose a scheme that utilizes weak-field-induced quantum beats to investigate the electronic coherences of atoms driven by a strong attosecond extreme ultraviolet(XUV)*** technique involves using a strong XUV pump pulse to excite and ionize atoms and a time-delayed weak short pulse to probe the photoelectron *** theoretical analysis demonstrates that the information regarding the bound states,initiated by the strong pump pulse,can be precisely reconstructed from the weak-field-induced quantum beat *** examine this scheme,we apply it to the attosecond XUV laser-induced ionization of hydrogen atoms by solving a three-dimensional time-dependent Schr?dinger *** work provides an essential reference for reconstructing the ultrafast dynamics of bound states induced by strong XUV attosecond pulses.

关键词： attosecond pulse bound-state dynamics quantum beats

MEMS-actuated terahertz metamaterials driven by phase-transition materials

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Frontiers of Optoelectronics 2024年第2期17卷 23-32页

作者： Zhixiang Huang Weipeng Wu Eric Herrmann Ke Ma Zizwe A.Chase Thomas A.Searles M.Benjamin Jungfleisch Xi Wang department of Materials Science and engineering College of EngineeringUniversity of DelawareNewarkDE 19716USA department of physics and Astronomy College of Arts and SciencesUniversity of DelawareNewarkDE 19716USA department of Electrical and Computer engineering College of EngineeringUniversity of Illinois ChicagoChicagoIL 60607USA

The non-ionizing and penetrative characteristics of terahertz(THz)radiation have recently led to its adoption across a variety of *** effectively utilize THz radiation,modulators with precise control are *** most recent THz modulators manipulate the amplitude,frequency,or phase of incident THz radiation,considerably less progress has been made toward THz polarization *** methods for polarization control suffer from high driving voltages,restricted modulation depth,and narrow band capabilities,which hinder device performance and broader ***,an ideal THz modulator that offers high modulation depth along with ease of processing and operation is *** this paper,we propose and realize a THz metamaterial comprised of microelectromechanical systems(MEMS)actuated by the phase-transition material vanadium dioxide(VO_(2)).Simulation and experimental results of the three-dimensional metamaterials show that by leveraging the unique phase-transition attributes of VO_(2),our THz polarization modulator offers notable advancements over existing designs,including broad operation spectrum,high modulation depth,ease of fabrication,ease of operation condition,and continuous modulation *** enhanced features make the system a viable candidate for a range of THz applications,including telecommunications,imaging,and radar systems.

关键词： Metamaterials MEMS THz VO_(2) Phase-transition material

Detailed characterization of kHz-rate laser-driven fusion at a thin liquid sheet with a neutron detection suite

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High Power Laser Science and engineering 2024年第1期12卷 13-23页

作者： Benjamin M.Knight Connor M.Gautam Colton R.Stoner Bryan V.Egner Joseph R.Smith Chris M.Orban Juan J.Manfredi Kyle D.Frische Michael L.Dexter Enam A.Chowdhury Anil K.Patnaik department of engineering physics Air Force Institute of TechnologyWPAFBOHUSA physics department Marietta CollegeMariettaOHUSA department of physics The Ohio State UniversityColumbusOHUSA department of Materials Science and engineering and Department of Electrical and Computer ScienceThe Ohio State UniversityColumbusOHUSA Intense Energy Solutions LLCPlain CityOHUSA

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(<1 μm) D_2O liquid sheet employing a measurement suite. At relativistic intensity(~ 5 × 10^(18)W/cm^(2))and high repetition rate(1 kHz), the system produces deuterium±deuterium(D-D) fusion, allowing for consistent neutron generation. Evidence of D-D fusion neutron production is verified by a measurement suite with three independent detection systems: an EJ-309 organic scintillator with pulse-shape discrimination, a ~3He proportional counter and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 MeV. Particle-in-cell simulations using the WarpX code support significant neutron production from D-D fusion events in the laser±target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-demand test bed for radiation hardening and imaging applications.

关键词： high-repetition-rate laser-driven fusion laser-plasma interaction liquid target neutron detectors

Origin of tradeoff between movement velocity and attachment duration of kinesin motor on a microtubule

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Chinese physics B 2024年第2期33卷 557-566页

作者：刘玉颖张志强 department of physics College of ScienceChina Agricultural UniversityBeijing 100083China Basic Ministry Space Engineering UniversityBeijing 101416China

Kinesin-1 motor protein is a homodimer containing two identical motor domains connected by a common long coiledcoil stalk via two flexible neck linkers. The motor can step on a microtubule with a velocity of about 1 μm·s-1and an attachment duration of about 1 s under physiological conditions. The available experimental data indicate a tradeoff between velocity and attachment duration under various experimental conditions, such as variation of the solution temperature,variation of the strain between the two motor domains, and so on. However, the underlying mechanism of the tradeoff is unknown. Here, the mechanism is explained by a theoretical study of the dynamics of the motor under various experimental conditions, reproducing quantitatively the available experimental data and providing additional predictions. How the various experimental conditions lead to different decreasing rates of attachment duration versus velocity is also explained.

关键词： motor protein velocity detachment time processivity

Recent Developments in Authentication Schemes Used in Machine-Type Communication Devices in Machine-to-Machine Communication: Issues and Challenges

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Computers, Materials & Continua 2024年第4期79卷 93-115页

作者： Shafi Ullah Sibghat Ullah Bazai Mohammad Imran Qazi Mudassar Ilyas Abid Mehmood Muhammad Asim Saleem Muhmmad Aasim Rafique Arsalan Haider Ilyas Khan Sajid Iqbal Yonis Gulzar Kauser Hameed department of Computer engineering Balochistan University of Information TechnologyEngineering and Management SciencesQuetta87300Pakistan department of Information Technology Balochistan University of Information TechnologyEngineeringand Management SciencesQuetta87300Pakistan department of Information Systems College of Computer Sciences and Information TechnologyKing Faisal UniversityHofuf in Al-Ahsa31982Saudi Arabia department of management Information Systems College of Business AdministrationKing Faisal UniversityHofuf in Al-Ahsa31982Saudi Arabia department of Software engineering College of ComputingRiphah International UniversityFaisalabad44000Pakistan department of Electrical engineering Balochistan University of Information Technology Engineeringand Management SciencesQuetta87300Pakistan department of Mathematics College of Science Al-ZulfiMajmaah UniversityAl-Majmaah11952Saudi Arabia

Machine-to-machine (M2M) communication plays a fundamental role in autonomous IoT (Internet of Things)-based infrastructure, a vital part of the fourth industrial revolution. Machine-type communication devices(MTCDs) regularly share extensive data without human intervention while making all types of decisions. Thesedecisions may involve controlling sensitive ventilation systems maintaining uniform temperature, live heartbeatmonitoring, and several different alert systems. Many of these devices simultaneously share data to form anautomated system. The data shared between machine-type communication devices (MTCDs) is prone to risk dueto limited computational power, internal memory, and energy capacity. Therefore, securing the data and devicesbecomes challenging due to factors such as dynamic operational environments, remoteness, harsh conditions,and areas where human physical access is difficult. One of the crucial parts of securing MTCDs and data isauthentication, where each devicemust be verified before data transmission. SeveralM2Mauthentication schemeshave been proposed in the literature, however, the literature lacks a comprehensive overview of current M2Mauthentication techniques and the challenges associated with them. To utilize a suitable authentication schemefor specific scenarios, it is important to understand the challenges associated with it. Therefore, this article fillsthis gap by reviewing the state-of-the-art research on authentication schemes in MTCDs specifically concerningapplication categories, security provisions, and performance efficiency.

关键词： Authentication cyber security internet of things machine-type communication devices machine-to-machine communication

A dynamic exploratory hybrid modelling framework for simulating complex and uncertain system

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Journal of Safety Science and Resilience 2024年第2期5卷 167-178页

作者： Gangqiao Wang Han Xing Yongqiang Chen Yi Liu Institute of Big Data Inteligent management and Decision-making College of ManagementShenzhen UniversityShenzhen 518060China School of Safety Science Tsinghua UniversityBejing 100084China department of Mechanics and engineering Science College of EngineeringPeking UniversityBejing 100871China

Complex disaster systems involve various components and mechanisms that could interact in complex ways and change over time,leading to significant deep *** to deep uncertainty,decision-makers have severe inadequacy of knowledge and often encounter unpredictable surprises that may emerge in the future,thus making it difficult to specify appropriate models and parameters to describe the system of *** this paper,we propose a dynamic exploratory hybrid modeling framework that fits data,models,and computational ex-periments together to simulate complex systems with deep *** the framework,one needs to develop multiple plausible models from a hybrid modeling perspective and perform enormous computational experi-ments to explore the diversity of future ***-time data is then incorporated into diverse forecasts to dynamically adjust the simulation *** ultimately enables an ongoing modeling and analysis process in which deep uncertainty would be gradually *** approach has been applied to a human-involved car-following system simulation under complex traffic *** results show that the proposed approach can improve the prediction accuracy while enhancing the sensitivity of the simulation system to uncertain changes in the system of interest.

关键词： Disaster modeling and analysis Deepuncertainty Hybrid modeling Adaptivesimulation