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Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.Huang k.Jiang C.N.Wu H.peng p.C.hen R.Li H.B.Zhuo C.T.Zhou Shenzhen key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Long Term X-Ray Spectral Variations of the Seyfert-1 Galaxy Mrk 279

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Research in Astronomy and Astrophysics 2024年第6期24卷 307-314页

作者： k.Akhila Ranjeev Misra Savithri H.Ezhikode k.Jeena Department of physics Providence Women’s CollegeUniversity of CalicutKerala 673009India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PB No.4GaneshkhindPune 411007India Department of physics and Electronics CHRIST(Deemed to be University)Hosur Main RoadBangalore 560029India

We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–*** use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the *** X-ray spectrum can be modeled as a double Comptonization along with the presence of neutral Fe kαline emission,at all *** determined the source’s X-ray flux and luminosity at these different *** find significant variations in the source’s flux *** also investigate the variations in the source’s spectral components during the observation *** find that the photon index and hence the spectral shape follow the variations only over longer time *** probe the correlations between fluxes of different bands and their photon indices,and found no significant correlations between the parameters.

关键词： galaxies:Seyfert galaxies:individual(Mrk 335) X-rays:galaxies

Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and Radiation at Extremes 2024年第4期9卷 80-89页

作者： J.Lutgert p.Hesselbach M.Schorner V.Bagnoud R.Belikov p.Drechsel B.Heuser O.SHumphries p.katrik B.Lindqvist C.Qu R.Redmer D.Riley G.Schaumann S.Schumacher A.Tauschwitz D.Varentsov k.Weyrich X.Yu B.Zielbauer Zs.Major p.Neumayer D.kraus Institut fur physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GSI Helmholtzzentrum fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstr.40001328 DresdenGermany European XFEL GmbH Holzkoppel 422869 SchenefeldGermany Centre for plasma physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State key Laboratory of Nuclear physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut Jena Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy *** this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 k,in agreement with predictions fromstopping power *** simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,butdo indicate the onset of fracture in the diamond *** experiments pave the way for future studies at the Facility for Antiproton andIon Research,where a substantially increased intensity of the heavy ion beam will be available.

关键词： heated intense structure

Applicability limits of the DAX test in plastic bonded explosives

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Defence Technology（防务技术） 2024年第6期36卷 64-70页

作者： Martin künzel Jindrich kucera Jiri pachman OZM Research Bliznovice 32Hrochuv Tynec 53862Czech Republic Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceStudentska 95Pardubice 53210Czech Republic

The Disc Acceleration e Xperiment(DAX)is one of the most recent experimental methods of performance characterization of new energetic materials.A cylindrical explosive charge accelerates a thin metallic disc and its velocity is measured continuously using photonic Doppler *** detonation velocity is measured *** DAX test can be used to obtain the Chapman-Jouguet(CJ)detonation pressure and to describe detonation products expansion using reduced amount of explosive.A series of DAX tests was performed at various charge diameters and disc thicknesses with Semtex 1 A plastic bonded explosive and sensitized *** DAX-like evaluation was also applied to previously measured data of Semtex 1A and A-IX-1 *** optimum disc thickness is determined by the disc to explosive mass ratio of *** repeatability of the Semtex 1 A detonation pressure results is about four times lower compared to the pressed and liquid explosives.

关键词： Flyer plate Detonation pressure photonic Doppler velocimetry Semtex

Hybrid prairie Dog and Beluga Whale Optimization Algorithm for Multi-Objective Load Balanced-Task Scheduling in Cloud Computing Environments

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China Communications 2024年第7期21卷 307-324页

作者： k Ramya Senthilselvi Ayothi Department of Computer Science and Engineering SRM Institute of Science and TechnologyRamapuramChennaiTamil Nadu 600089India

The cloud computing technology is utilized for achieving resource utilization of remotebased virtual computer to facilitate the consumers with rapid and accurate massive data *** utilizes on-demand resource provisioning,but the necessitated constraints of rapid turnaround time,minimal execution cost,high rate of resource utilization and limited makespan transforms the Load Balancing(LB)process-based Task Scheduling(TS)problem into an Np-hard optimization *** this paper,Hybrid prairie Dog and Beluga Whale Optimization Algorithm(HpDBWOA)is propounded for precise mapping of tasks to virtual machines with the due objective of addressing the dynamic nature of cloud *** capability of HpDBWOA helps in decreasing the SLA violations and Makespan with optimal resource *** is modelled as a scheduling strategy which utilizes the merits of pDOA and BWOA for attaining reactive decisions making with respect to the process of assigning the tasks to virtual resources by considering their priorities into *** addresses the problem of pre-convergence with wellbalanced exploration and exploitation to attain necessitated Quality of Service(QoS)for minimizing the waiting time incurred during TS *** further balanced exploration and exploitation rates for reducing the makespan during the task allocation with complete awareness of VM *** results of the proposed HpDBWOA confirmed minimized energy utilization of 32.18% and reduced cost of 28.94% better than approaches used for *** statistical investigation of the proposed HpDBWOA conducted using ANOVA confirmed its efficacy over the benchmarked systems in terms of throughput,system,and response time.

关键词： Beluga Whale Optimization Algorithm(BWOA) cloud computing Improved Hopcroft-karp algorithm Infrastructure as a Service(IaaS) prairie Dog Optimization Algorithm(pDOA) Virtual Machine(VM)

Role of marine natural products in the development of antiviral agents against SARS‑CoV‑2:potential and prospects

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Marine Life Science & Technology 2024年第2期6卷 280-297页

作者： D.p.Nagahawatta N.M.Liyanage Thilina U.Jayawardena H.H.A.C.k.Jayawardhana Seong‑Hun Jeong Hyung‑Jun kwon You‑Jin Jeon Department of Marine Life Sciences Jeju National UniversityJeju 690-756Republic of Korea Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresTrois-RivièresQC G8Z 4M3Canada Marine Science Institute Jeju National UniversityJeju 63333Republic of Korea Functional Biomaterial Research Center Korea Research Institute of Bioscience and BiotechnologyJeongeup-siRepublic of Korea

A novel coronavirus,known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has surfaced and caused global concern owing to its ***-CoV-2 is the causative agent of coronavirus disease 2019;however,it was only discovered at the end of the year and was considered a pandemic by the World Health ***,the develop-ment of novel potent inhibitors against SARS-CoV-2 and future outbreaks is urgently *** naturally occurring bioactive substances have been studied in the clinical setting for diverse *** intricate infection and replication mechanism of SARS-CoV-2 offers diverse therapeutic drug targets for developing antiviral medicines by employing natural products that are safer than synthetic *** natural products(MNps)have received increased attention in the development of novel drugs owing to their high diversity and ***,this review article investigates the infection and replication mechanisms,including the function of the SARS-CoV-2 genome and ***,we highlighted anti-SARS-CoV-2 therapeutic intervention efforts utilizing MNps and predicted SARS-CoV-2 inhibitor design.

关键词： SARS-CoV-2 Marine natural products Drug targets Inhibitors

SARS-CoV-2 spike protein-ACE2 interaction increases carbohydrate sulfotransferases and reduces N-acetylgalactosamine-4-sulfatase by p38 MApk

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1174-1185页

作者： Sumit Bhattacharyya Joanne k.Tobacman Jesse Brown VA Medical Center and University of Illinois at Chicago ChicagoIL 60612USA

Immunostaining in lungs of patients who died with CovID-19 infection showed increased intensity and distribution of chondroitin sulfate and decline in N-acetylgalactostamine-4-sulfatase(Arylsulfatase B;ARSB).To explain these findings,human small airway epithelial cells were exposed to the SARS-CoV-2 spike protein receptor binding domain(SpRBD)and transcriptional mechanisms were ***-p38 MApk and phospho-SMAD3 increased following exposure to the SpRBD,and their inhibition suppressed the promoter activation of the carbohydrate sulfotransferases CHST15 and CHST11,which contributed to chondroitin sulfate *** in ARSB was mediated by phospho-38 MApk-induced N-terminal Rb phosphorylation and an associated increase in Rb-E2F1 binding and decline in E2F1 binding to the ARSB *** increases in chondroitin sulfotransferases were inhibited when treated with phospho-p38-MApk inhibitors,SMAD3(SIS3)inhibitors,as well as antihistamine desloratadine and antibiotic *** the mouse model of carrageenan-induced systemic inflammation,increases in phosphop38 MApk and expression of CHST15 and CHST11 and declines in DNA-E2F binding and ARSB expression occurred in the lung,similar to theobserved effects in this SpRBD model of COVID-19 *** accumulation of chondroitin sulfates is associated with fibrotic lung conditions and diffuse alveolar damage,increased attention to p38-MApk inhibition may be beneficial in amelioratingCovid-19infections.

关键词： ACE2 lung inhibited

process engineering of demineralisation of moderate to high ash Indian coals through NaOH‑HCl leaching and HF leaching

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International Journal of Coal Science & Technology 2024年第2期11卷 111-122页

作者： Heena Dhawan D.k.Sharma ANRF Ministry of ScienceNew DelhiIndia Department of Energy Science and Engineering Indian Institute of Technology DelhiNew Delhi 110016India

Chemical leaching of coals would be required to produce cleaner coals for some special applications where physical benefi-ciation may not be effective *** would also help in recovering Li and rare earth metals besides in the sequestration of CO_(2).About 20 Indian coals having complexly distributed moderate to high ash contents were sequentially treated with various alkali–acid such as NaOH-HCl,HF,HCl,HCl-HF,and NaOH-HCl-HF *** aimed to establish and design the best stepwise sequential process for the highest degree of demineralisation through a chemical leaching *** and process intensification studies were carried *** than 80%demineralisation of Madhaipur and Neemcha coals was observed using the best sequential treatment designed *** repeated stepwise treatment of the alkali and the acid was also studied,which was found to significantly enhance the degree of demineralisation of *** integrated process of alkali–acid leaching followed by solvent extraction(Organo-refining)and vice versa of the treated coal was also studied for producing cleaner coals.

关键词： Alkali–acid leaching Demineralisation Integrated process Rare earth elements

Liquid superlubricity of lubricants containing hydroxyl groups and their aqueous solution under rolling/sliding conditions

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Friction 2024年第1期12卷 164-173页

作者： Tomáš pOLÁČEk petr ŠpERkA Ivan kŘUpkA Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic

Macroscale rolling/sliding conditions are in the superlubricity,a little-studied topic so *** purpose of this paper is to examine the formation of elastohydrodynamic lubrication(EHL)films by water-based lubricants(glycerol and polyethylene glycol(pEG)),providing superlubricous *** were carried out on an optical ball-on-disc tribometer under rolling/sliding *** film thickness was measured by the thin film colorimetric interferometry,and the viscosity of liquids was measured by rotational and high-pressure falling body *** results show that tribochemical reactions are not the mandatory reason for friction to reach the superlubricity level when using the water-based *** studied liquids themselves are almost *** the addition of water,the signs of shear thinning behavior disappear even *** conditions for this type of lubricant can be predicted using the known Hamrock–Dowson *** anomaly in the thickness of the lubricants was observed as an abrupt change at certain *** more pEG there is in the lubricant,the higher the thickness at the beginning of the jump.

关键词： macroscale superlubricity super low traction water-based lubricants elastohydrodynamic lubrication(EHL) film thickness