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Nuclear science and Techniques 2024年第8期35卷 1-4页

作者： marcus Bleicher Institute for Theoretical Physics Goethe-University FrankfurtMax‑von‑Laue‑Str.160438 FrankfurtGermany Helmholtz Research Academy Hesse for FAIR(HFHF) GSI HelmholtzzentrumCampusFrankfurtGermany

A new approach based on relativistic kinetic equations is proposed to solve the long-standing puzzle of light cluster formation, also called nucleosynthesis, in high-energy heavy-ion collisions. This method addresses the tension between sTAR data and previous studies relying on either statistical equilibrium or coalescence approaches.

关键词： synthesis relativistic cluster

Comparison of a spectral Bin and Two Multi-Moment Bulk Microphysics schemes for supercell simulation:Investigation into key Processes Responsible for Hydrometeor Distributions and Precipitation

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Advances in Atmospheric sciences 2024年第5期41卷 784-800页

作者： marcus JOHNsON Ming XUE Youngsun JUNG Center for Analysis and Prediction of storms University of OklahomaNormanOK 73072USA school of Meteorology University of OklahomaNormanOK 73072USA Office of science and Technology Integration National Weather ServiceSilver SpringMD 20910USA

There are more uncertainties with ice hydrometeor representations and related processes than liquid hydrometeors within microphysics parameterization(MP)schemes because of their complicated geometries and physical *** supercell simulations are produced using the WRF model coupled with“full”Hebrew University spectral bin MP(HU-sBM),and NssL and Thompson bulk MP(BMP)***-sBM downdrafts are typically weaker than those of the NssL and Thompson simulations,accompanied by less rain ***-sBM produces more cloud ice(plates),graupel,and hail than the BMPs,yet precipitates less at the *** limiting mass bins(and subsequently,particle size)of rimed ice in HU-sBM and slower rimed ice fall speeds lead to smaller melting-level net rimed ice fluxes than those of the *** from plates in HU-sBM,together with snow–graupel collisions,leads to a greater snow contribution to rain than those of the *** HU-sBM’s fall speeds using the formulations of the BMPs after aggregating the discrete bin values to mass mixing ratios and total number concentrations increases net rain and rimed ice ***,they are smaller in magnitude than bulk rain,NssL hail,and Thompson graupel net fluxes near the ***,the melting-layer net rimed ice fluxes are reduced when the fall speeds for the NssL and Thompson simulations are calculated using HU-sBM fall speed formulations after discretizing the bulk particle size distributions(PsDs)into spectral *** results highlight precipitation sensitivity to storm dynamics,fall speed,hydrometeor evolution governed by process rates,and MP PsD design.

关键词： precipitation spectral bin microphysics bulk microphysics parameterization microphysics processes WRF model supercell storm

Insights into the hydrogen evolution reaction in vanadium redox flow batteries:A synchrotron radiation based X-ray imaging study

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Journal of Energy Chemistry 2024年第4期91卷 132-144页

作者： kerstin köble Alexey Ershov kangjun Duan Monja schilling Alexander Rampf Angelica Cecilia TomášFaragó marcus Zuber Tilo Baumbach Roswitha Zeis Helmholtz Institute Ulm Karlsruhe Institute of Technology89081 UlmGermany Laboratory for Applications of synchrotron Radiation Karlsruhe Institute of Technology76131 KarlsruheGermany Institute for Photon science and synchrotron Radiation Karlsruhe Institute of Technology76344 Eggenstein-LeopoldshafenGermany Department of Electrical Electronicsand Communication EngineeringFaculty of EngineeringFriedrich-Alexander-Universität Erlangen-Nürnberg(FAU)91058 ErlangenGermany Department of Mechanical and Industrial Engineering University of TorontoToronto M5S 3G8OntarioCanada

The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency ***,a deeper understanding of this process and the accompanying bubble formation is *** benchmarking study locally analyzes the bubble distribution in thick,porous electrodes for the first time using deep learning-based image segmentation of synchrotron X-ray *** large three-dimensional data set was processed precisely in less than one minute while minimizing human errors and pointing out areas of increased HER activity in *** study systematically varies the electrode potential and material,concluding that more negative electrode potentials of-200 m V *** hydrogen electrode(RHE)and lower cause more substantial bubble formation,resulting in bubble fractions of around 15%–20%in carbon felt ***,the bubble fractions stay only around 2%in an electrode combining carbon felt and carbon *** detected areas with high HER activity,such as the border subregion with more than 30%bubble fraction in carbon felt electrodes,the cutting edges,and preferential spots in the electrode bulk,are potential-independent and suggest that larger electrodes with a higher bulk-to-border ratio might reduce HER-related performance *** described combination of electrochemical measurements,local X-ray microtomography,AI-based segmentation,and 3D morphometric analysis is a powerful and novel approach for local bubble analysis in three-dimensional porous electrodes,providing an essential toolkit for a broad community working on bubble-generating electrochemical systems.

关键词： Vanadium redox flow battery synchrotron X-ray imaging Tomography Hydrogen evolution reaction Gas bubbles Deep learning

Feature extraction for machine learning-based intrusion detection in IoT networks

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Digital Communications and Networks 2024年第1期10卷 205-216页

作者： Mohanad sarhan siamak Layeghy Nour Moustafa marcus Gallagher Marius Portmann University of Queensland BrisbaneQLD4072Australia University of New south Wales CanberraACT2612Australia

A large number of network security breaches in IoT networks have demonstrated the unreliability of current Network Intrusion Detection systems(NIDss).Consequently,network interruptions and loss of sensitive data have occurred,which led to an active research area for improving NIDs *** an analysis of related works,it was observed that most researchers aim to obtain better classification results by using a set of untried combinations of Feature Reduction(FR)and Machine Learning(ML)techniques on NIDs ***,these datasets are different in feature sets,attack types,and network ***,this paper aims to discover whether these techniques can be generalised across various *** ML models are utilised:a Deep Feed Forward(DFF),Convolutional Neural Network(CNN),Recurrent Neural Network(RNN),Decision Tree(DT),Logistic Regression(LR),and Naive Bayes(NB).The accuracy of three Feature Extraction(FE)algorithms is detected;Principal Component Analysis(PCA),Auto-encoder(AE),and Linear Discriminant Analysis(LDA),are evaluated using three benchmark datasets:UNsW-NB15,ToN-IoT and *** PCA and AE algorithms have been widely used,the determination of their optimal number of extracted dimensions has been *** results indicate that no clear FE method or ML model can achieve the best scores for all *** optimal number of extracted dimensions has been identified for each dataset,and LDA degrades the performance of the ML models on two *** variance is used to analyse the extracted dimensions of LDA and ***,this paper concludes that the choice of datasets significantly alters the performance of the applied *** believe that a universal(benchmark)feature set is needed to facilitate further advancement and progress of research in this field.

关键词： Feature extraction Machine learning Network intrusion detection system IoT

Transforming nanoscale VO_(2)(B) into a scalable sodium-ion electrode

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Nano Research 2024年第10期17卷 8809-8818页

作者： Yunkai Luo swetha Chandrasekaran Bintao Hu Randy Chen marcus Worsley Bruce Dunn Department of Materials science and Engineering University of CaliforniaLos AngelesCA 90095USA Lawrence Livermore National Laboratory CA 94550USA

The intermittent nature of renewable energies requires highly reliable grid-level energy storage approaches.A critical consideration in developing this technology is the areal capacity which determines battery performance and influences the cost of battery *** related importance is finding new ways of developing scalable *** recent years,threedimensional(3D)printing of conductive scaffolds has emerged as an alternative to overcome the scalability limitations of commercial tape cast *** research carried out in the current study demonstrates a successful scalability pathway for nanoscale VO_(2)(B),a desirable cathode for sodium-ion batteries which has a nano-flower morphology with a crystallite sizesiting VO_(2)(B)onto a graphene aerogel scaffold,we were able to achieve mass loading of over 100 mg·cm^(-2) and still possess an areal capacity of 10 mAh·cm^(-2) at a current density of 5 mA·cm^(-2).Moreover,after 1000 cycles,these electrodes retained 75% to 80% of their initial *** at high loading levels,the electrodeposited VO_(2)(B)exhibits pseudocapacitive material signatures such as a box-like voltammetry response,linear galvanostatic response,and no phase change upon *** scalability of the VO_(2)(B)electrode is demonstrated in a series of experiments which show the areal capacity to scale upon increase in both mass loading and electrode thickness,with only small changes in specific *** study establishes that nanoscale materials can be scaled up to achieve thick electrodes without compromising their electrochemical properties.

关键词： nano VO_(2)(B) sodium-ion battery scalable electrodes three-dimensional(3D)printed scaffold additive manufacturing

The global regulation of c-di-GMP and cAMP in bacteria

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mLife 2024年第1期3卷 42-56页

作者： Cong Liu Rui shi marcus s.Jensen Jingrong Zhu Jiawen Liu Xiaobo Liu Di sun Weijie Liu Jiangsu key Laboratory of Phylogenomics&Comparative Genomics School of Life SciencesJiangsu Normal UniversityXuzhouChina key Laboratory of Metabolic Engineering and Biosynthesis Technology Ministry of Industry and Information TechnologyNanjing University of Science and TechnologyNanjingChina

Nucleotide second messengers are highly versatile signaling molecules that regulate a variety of key biological processes in *** best-studied examples are cyclic AMP(cAMP)and bis-(3'-5')-cyclic dimeric guanosine monophosphate(c-di-GMP),which both act as global *** regulatory frameworks of c-di-GMP and cAMP in bacteria show several parallels but also significant *** this review,we llustrate the global regulatory models of the two nucleotide second messengers,compare the different regulatory frameworks between c-di-GMP and cAMP,and discuss the mechanisms and physiological significance of cross-regulation between c-di-GMP and cAMP.c-di-GMP responds to numerous signals de-pendent on a great number of metabolic enzymes,and it regulates various signal transduction pathways through its huge number of effectors with varying *** contrast,due to the limited quantity,the cAMP metabolic enzymes and its major effector are regulated at different levels by diverse *** performs its global regulatory function primarily by controlling the transcription of a large number of genes via cAMP receptor protein(CRP)in most *** review can help us understand how bacteria use the two typical nucleotide second messengers to effectively coordinate and integrate various physiological processes,providing theoretical guidelines for future research.

关键词： bacteria cAMP c-di-GMP cross-regulation CRP

Furfural residues derived nitrogen-sulfur co-doped sheet-like carbon: An excellent electrode for dual carbon lithium-ion capacitors

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Green Energy & Environment 2024年第9期9卷 1427-1439页

作者： Xiaoying Guo Yan Qiao Zonglin Yi Christian marcus Pedersen Yingxiong Wang Xiaodong Tian Peide Han College of Materials science and Engineering Taiyuan University of Technology state key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of sciences CAs key Laboratory of Carbon Materials Institute of Coal Chemistry Chinese Academy of Sciences Department of Chemistry University of Copenhagen Universitetsparken 5 College of Chemistry Taiyuan University of Technology

The state-of-the-art lithium-ion capacitors （LICs）,consisting of high-capacity battery-type anode and high-rate capacitor-type cathode,can deliver high energy density and large power density when comparing with traditional supercapacitors and lithium-ion batteries,***,the ion kinetics mismatch between cathode and anode leads to unsatisfied cycling lifetime and anode *** efforts have been devoted to solving the abovementioned *** promising strategy is altering high conductive hard carbon anode with excellent structural stability to match with activated carbon cathode,assembling dual-carbon *** this contribution,one-pot in-situ expansion and heteroatom doping strategy was adopted to prepare sheet-like hard carbon,while activated carbon was obtained involving *** persulfate was used as expanding and doping agent *** furfural residues （FR） were served as carbon *** resulting hard carbon （FRNs-HC） and activated carbon （FRNs-AC）show excellent electrochemical performance as negative and positive electrodes in a lithium-ion battery （LIB）.To be specific,374.2 m Ah g-1and 123.1 m Ah g-1can be achieved at 0.1 A g-1and 5 A g-1when FRNs-HC was tested as *** combined with a highly porous carbon cathode (sBET=2961 m2g-1) synthesized from the same precursor,the LIC showed high specific energy of147.67 Wh kg-1at approximately 199.93 W kg-1,and outstanding cycling life with negligible capacitance fading over 1000 *** study could lead the way for the development of heteroatom-doped porous carbon nanomaterials applied to Li-based energy storage applications.

关键词： Furfural residue Ammonium persulfate sheet-like carbon Lithium-ion capacitors Hard carbon

Acetic acid additive in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

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Journal of Magnesium and Alloys 2024年第2期12卷 825-839页

作者： Yaqing Zhou Fan sun Gunahua Lin sandrine Zanna Antoine seyeux Philippe marcus Jolanta´swiatowska Chimie ParisTech-CNRs PSL UniversityInstitut de Recherche de Chimie Paris11 rue Pierre et Marie CurieParis 75005France

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density,environmental sustainability,and ***,the fast hydrogen evolution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low ***,the conventionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additive as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is *** resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching~1.8 V for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to over 360 h,in contrast to only~17 h observed in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid *** thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

关键词： Acetic acid additive in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film surface characterization Hydrogen evolution

A GHz chirped amplitude-modulated laser for high-contrast plasma gratings

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High Power Laser science and Engineering 2024年第1期12卷 74-83页

作者： Michael Valdman Amir Hen Gilad marcus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The generation and control of large amplitude plasma gratings and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this goal. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation high-frequency modulation autoresonance ion acoustic wave