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Collective coherent emission of electrons in strong laser fields and perspective for hard x-ray lasers

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Matter and Radiation at extremes 2024年第2期9卷 1-3页

作者： e.G.Gelfer A.M.Fedotov o.Klimo S.Weber extreme Light Infrastructure eRIC ELI Beamlines Facility25241 Dolní BřežanyCzech Republic HiLASe Centre Institute of Physics of the Czech Academy of Sciences25241 Dolní BřežanyCzech Republic National Research Nuclear University MePhI Moscow 115409Russia FNSPe Czech Technical University in Prague11519 PragueCzech Republic

Coherent motion of particles in a plasma can imprint itself on *** recent advent of high-power lasers—allowing the nonlinear inverse Compton-scattering regime to be reached—has opened the possibility of looking at collective effects in laser–plasma *** certain conditions,the collective interaction of many electrons with a laser pulse can generate coherent radiation in the hard x-ray *** perspective paper explains the limitations under which such a regime might be attained.

关键词： laser scattering coherent

Highly Defective Dark Tio_(2) Modified with Pt: effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： e.D.Fakhrutdinova o.A.Reutova T.A.Bugrova I.Yu.ovsyuk L.S.Kibis o.A.Stonkus D.B.Vasilchenko o.V.Vodyankina V.A.Svetlychnyi National Research Tomsk State University TomskRussia 634050 Novosibirsk State University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed Co adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (oH) _(2) (No _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the Tio _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/Tio_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)Tio_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

Is it possible to run after positive affective experiences instead of health benefits without tackling social inequalities?

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Journal of Sport and Health Science 2024年第6期13卷 756-758页

作者： Raphael H.o.Araujo Andre o.Werneck Gilmar M.de Jesus Danilo R.P.Silva Graduation Program in Health Sciences Londrina State UniversityLondrina 86057-970Brazil School of Public Health The University of QueenslandBrisbane QLD 4006Australia Center for epidemiological Research in Nutrition and Health Department of NutritionSchool of Public HealthUniversidade de S~ao Paulo(USP)Sao Paulo 01246-904Brazil Department of Psychological Medicine Institute of PsychiatryPsychology and NeuroscienceKing’s College LondonLondon SE58AFUK Public Health Post-Graduate Program State University of Feira de SantanaFeira de Santana 44036-900Brazil Department of Physical education Federal University of SergipeSao Cristov~ao 490100-000Brazil

We recently read the opinion piece titled“Why people should run after positive affective experiences instead of health benefits”,which was carried out by Maltagliati et al.^(1)and published in the Journal of Sport and Health *** article started an important discussion about a physical activity(PA)promotion approach that encourages the use of affective experience to PA *** we agree with the authors’point of view and believe that its message can generate an important insight for PA promotion,the authors presented a scenario where behavior change seems to be exclusively dependent on the *** the existence of other barriers to an active lifestyle(e.g.,social inequalities)could enhance the authors’suggested approach because many people live in conditions that reduce their opportunities to engage in affective experiences related to PA;furthermore,affective experiences can vary depending on individual context.

关键词： promotion inequalities furthermore

Space Rocks-and Dust-Roll into Planetary Science Limelight

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engineering 2024年第8期39卷 3-6页

作者： Sean o’Neill 不详

Space sample retrieval is having a *** 24 September 2023,in a triumph of complex engineering,a US National Aeronau-tics and Space Administration(NASA)mission,oSIRUS-Rex(short for origins,spectral interpretation,resource identification,and security-regolith explorer;regolith is the surface layer of uncon-solidated rocks and dust/soil covering bedrock),successfully deliv-ered to earth a capsule containing the largest sample of asteroid material ever collected,captured from Bennu.

关键词： rock earth origin

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o el-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis el-Dib's frequency formula

Valorization of Tree Bark-Derived Suberin in Applications for the Bio-Based Composites Industry–A Recent Review

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Journal of Renewable Materials 2024年第6期12卷 1029-1042页

作者： Aleksandra Jeżo Institute of Wood Sciences and Furniture SGGWNowoursynowska St.159Warsaw02-776Poland

Bark extracts are sustainable sources of biopolymers and hold great promise for replacing fossil fuel-based polymers,for example,in wood-based *** addition to primary and secondary metabolites,tree bark also contains suberin,which plays a major role in protecting the tree from environmental *** is a natural aliphatic-aromatic cross-linked polyester present in the cell walls of both normal and damaged external tissues,the main component of which are long-chain aliphatic *** main role as a plant ingredient is to protect against microbiological factors and water *** of the most important suberin monomers are suberin fatty acids,known for their hydrophobic and barrier ***,due to the diverse chemical composition of suberin,it is an attractive alternative to hydrocarbon-based *** its potential is recognized,it is not widely used in biocomposites technology,including wood-based composites and the polymer *** article will discuss the current knowledge about the potential of suberin and its components in biocomposites technology,which will include surface finishes,composite adhesives and polymer blends.

关键词： Suberin suberinic acids wood composites biocomposites biopolyester

Making topological protein links using enzymatic reactions

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National Science Review 2024年第3期11卷 50-51页

作者： Roger Castells-Graells Todd o.Yeates Department of Chemistry and Biochemistry University of California UCLA-Doe Institute for Genomics and Proteomics

Proteins are exceedingly complex molecules though, at their heart, they are essentially linear polymers. Pull at their ends and one obtains an extended backbone. While that is true in most cases, some natural proteins... 详细信息

关键词： DeSIGN

Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of optoelectronics 2024年第2期17卷 87-97页

作者： o.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi e.Diez J.e.Velázquez-Pérez Y.M.Meziani J.M.Caridad J.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de excelencia en Luz y Materia estructurada(LUMeS) University of Salamanca37008 SalamancaSpain Research Center for electronic and optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFeTs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFeT *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic

A synthetic microbial community used as a bioinoculant can overcome rice production constraints in acid soils

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Science China(Life Sciences) 2024年第5期67卷 1085-1086页

作者： Maureen o’Callaghan Shengjing Shi Resilient Agriculture Group AgResearchLincolnChristcurch 8140New Zealand

A customised synthetic microbial community(SynCom)composed of carefully selected rhizosphere-competent bacterial strains improved rice growth,yield and resistance to soil acidity and Al toxicity.

关键词： soil soils rhizosphere

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