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Cretaceous volcanic-intrusive magmatism in western Guangdong and its geological significance

science China Earth sciences 2006年第7期49卷 696-713页

作者： s. y. o’reilly GEMoC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

systematic zircon LA-ICPMs U-Pb dating reveals that Cretaceous volcanic-intrusive activities developed in western Guangdong. Representative volcanic rocks, i.e. Maanshan and Zhougongding rhyodacites, have zircon U-Pb isotopic ages of 100±1 Ma, and the intrusive ones in-cluding the Deqing monzonitic granite body and the Xinghua granodiorite body in the shidong com-plex, as well as the Tiaocun granodiorite body in the Guangping complex yield ages of 99±2 Ma, ca. 100 Ma, and 104±3 Ma respectively. The biotite-granites of the shidong complex main body (461±35 Ma) and that of the Guangping complex (444±6 Ma) are Caledonian. In spite of the big time interval between Cretaceous volcanic-intrusive magmatisms and Caledonian intrusive ones, both of them are characterized by enrichment in Rb, Th, Ce, Zr, Hf, sm, depletion in Ba, Nb, Ta, P, Ti, Eu, and weakly REE tetrad effect. Eu negative anomalies are: Cretaceous volcanic rocks (Eu/Eu*=0.74), Cretaceous intrusive rocks (Eu/Eu*=0.35―0.58), Caledonian biotite granites (Eu/Eu*=0.31―0.34). studies of sr-Nd isotope data show that all these igneous rocks have high initial 87sr/86sr ratios (0.7105―0.7518), and low εNd(t) values (?7.23―?11.39) with their Nd two-stage model ages ranging from 1.6―2.0 Ga, which suggest that they all derived from the Proterozoic crustal basement of southeast China. The occurrence of Cretaceous volcanic-intrusive magmatisms in western Guangdong is related with the important lithospheric extension event in southeast China (including Nanling region) at ca. 100 Ma. The “volcanic line” defined by the large scale Mesozoic intermediate-acidic volcanic magmatisms in southeast China may further extend to the southwest margin of Nanling region.

关键词： Cretaceous, volcanic-intrusive rocks, zircon U-Pb dating, sr-Nd isotope, western Guangdong.

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Leading directions and effective distance of larch offspring dispersal at the upper treeline in the Northern and Polar Urals, Russia

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Forest Ecosystems 2024年第5期11卷 603-617页

作者： P.A.Moiseev V.L.semerikov T.V.semerikova D.s.Balakin I.B.Vorobiev s.o.Viuykhin Institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesEkaterinburg620144Russia Center for Genetics and Life science Sirius University of Science and Technology354340SochiRussia

Climate has changed sufficiently over the last 150 years and forced out upper treeline advance at the most studied sites around the *** rate of advance has been extremely variable–from tens to hundreds meters in *** is because the degree at which tree frontal populations respond to climate change depends on the complex interaction of biological and physical *** resulting stand pattern is the consequence of the interaction between dispersal and survival functions.A few publications have addressed the question of how this pattern is *** order to understand how the spatial structure of tree stands was formed at the upper limit of their distribution in the Ural Mountains,we assessed the distance and direction of dispersal of offspring from maternal *** found that in frontal Larix sibirica ***,‘effective’dispersal of offspring ranges from 3 to 758 m(with a median of 20–33 m in open forest and 219 m in single-tree tundra in the Polar Urals and 107 m in open forest in the Northern Urals).We revealed that most of the offspring effectively dispersed not only in the direction of the prevailing winds,but also in the opposite direction up the slope,and the distance can reach 500–760 *** data obtained can be used to develop an individual-based model which is capable of simulating in detail the dynamics of tree stands at the upper limit of their growth and reliably predicting the future position and pattern of treeline ecotone as growth conditions continue to improve in the face of observed climate change.

关键词： Effective dispersal distance Upper treeline Parentage analysis Age estimation Terrestrial laser scanning Larix sibirica Ural mountains

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Addressing poxvirus challenges in the Middle East to enhance biosafety and biosecurity measures

Journal of Biosafety and Biosecurity

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Journal of Biosafety and Biosecurity 2024年第3期6卷 142-156页

作者： Laith N.AL-Eitan Haneen o.Ali Hana s.Abu Kharmah Maryam K.Alasmar Iliya y.Khair Ahmad H.Mihyar Department of Applied Biological sciences Jordan University of Science and Technology22110 IrbidJordan Department of Biotechnology and Genetic Engineering Jordan University of Science and Technology22110 IrbidJordan

The emergence and zoonotic transmission of poxviruses in the Middle East have been recognized as complex public health ***,a vast family of DNA viruses,can infect many hosts,including animals and *** Middle East has had multiple epidemics of poxvirus infections(e.g.,Monkeypox,smallpox,and Camelpox)that have raised concerns owing to their detrimental effects on livestock,wildlife,and sporadic human *** review aims to thoroughly examine the complexity of the epidemiological patterns,intricate genetic diversity,and several contributing factors that support the emergence and zoonotic transmission of poxviruses in the Middle *** aspects of poxviruses contribute to the emergence of endemics and zoonotic breakouts,such as the complex nature of human-animal interactions,environmental changes,and their subtle capacity for viral *** review was compiled in the hopes of contributing to the current understanding of poxvirus biology and its implications for human and animal health in the Middle *** provide a comprehensive overview of the most common poxviruses in the Middle East,including their classification,structure,replication cycle,pathogenesis,route of transmissions,and of how the Middle East has developed ways to mitigate these biological threats.

关键词： Pox viruses Middle East Emergence Zoonotic Transmission

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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

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sensing nanoscale electromagnetic forces when the heat is on

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National science Review 2024年第7期11卷 64-65页

作者： Eric o.Potma Department of Chemistry University of California

In scanning probe microscopy(sPM),a sharp tip scans across a sample to produce an image with nanometer-scale resolution or better. sPM contrast is derived from the physical interplay between the tip and the sample. A special class of sPM techniques measures forces when the tip–sample junction is illuminated by an external light source. Photo-induced forces can be sensitive to the optical properties of the sample, thus enabling nanoscale imaging with spectroscopic,material-specific contrast.

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Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： s.Tan Q.Wang y.Chen W.B.yao C.Z.Xiao J.F.Myatt school of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China school of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(sRss)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order sRss and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order sRss propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order sRss,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that sRss and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

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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

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Electron kinetic effects in back-stimulated Raman scattering bursts driven by broadband laser pulses

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Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： Q.K.Liu L.Deng Q.Wang X.Zhang F.Q.Meng y.P.Wang y.Q.Gao H.B.Cai s.P.Zhu Graduate school China Academy of Engineering PhysicsBeijing 100088China Institute of Applied Physics and Computational Mathematics Beijing 100094China school of Nuclear science and Technology University of Science and Technology of ChinaHefei 230026China shanghai Institute of Laser Plasma Shanghai 201800China HEDPs Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China school of Physics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(BsRs)bursts using particle-in-cell *** bursts occur during the nonlinear stage,causing reflectivity spikes and generating large numbers of hot ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate the interference of the broadband laser’s random intensity *** the simplified model,we isolate and characterize the spectrum of electron plasma *** spectrum changes from a sideband structure to a turbulence-like structure during the burst.A significant asymmetry in the spectrum is *** asymmetry is amplified and transferred to electron phase space by high-intensity broadband laser pulses,leading to violent vortex-merging and generation of hot *** proportion of hot electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate that kinetic effects profoundly influence the BsRs evolution driven by broadband lasers.

关键词： scattering kinetic simplified

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Metrology for sub-Rayleigh-length target positioning in~10^(22)W/cm^(2)laser-plasma experiments

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High Power Laser science and Engineering 2024年第3期12卷 90-105页

作者： E.A.Vishnyakov A.sagisaka K.ogura T.Zh.Esirkepov B.Gonzalez-Izquierdo C.D.Armstrong T.A.Pikuz s.A.Pikuz W.yan T.M.Jeong s.singh P.Hadjisolomou o.Finke G.M.Grittani M.Nevrkla C.M.Lazzarini A.Velyhan T.Hayakawa y.Fukuda J.K.Koga M.Ishino K.Kondo y.Miyasaka A.Kon M.Nishikino y.V.Nosach D.Khikhlukha I.P.Tsygvintsev D.Kumar J.Nejdl D.Margarone P.V.sasorov s.Weber M.Kando H.Kiriyama y.Kato G.Korn K.Kondo s.V.Bulanov T.Kawachi A.s.Pirozhkov ELI Beamlines Facility The Extreme Light Infrastructure ERICDolníBrežanyCzech Republic Kansai Institute for Photon science(KPsI) QSTKyotoJapan Central Laser Facility Rutherford Appleton LaboratorySTFCHarwell OxfordDidcotUK Institute for open and Transdisciplinary Research Initiatives Osaka UniversityOsakaJapan HB11 Energy Holdings FreshwaterAustralia Key Laboratory for Laser Plasmas(Ministry of Education) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFsA Shanghai Jiao Tong UniversityShanghaiChina Institute of Plasma Physics AsCR PragueCzech Republic FZU-Institute of Physics AsCR PragueCzech Republic Czech Technical University in Prague FNSPEPragueCzech Republic Institute of Laser Engineering Osaka UniversityOsakaJapan Institute of Physics National Academy of Sciences of UkraineKyivUkraine IsTEQ AR YerevanArmenia

Tight focusing with very small f-numbers is necessary to achieve the highest at-focus ***,tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance We describe several near-infrared,visible,ultraviolet and soft and hard X-ray diagnostics employed in a~10^(22)W/cm^(2)laser±plasma *** used nearly 10 J total energy femtosecond laser pulses focused into an approximately1.3-μm focal spot on 5±20μm thick stainless-steel *** discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5μm accuracy(i.e.,around half of the short Rayleigh length)and show that several diagnostics(in particular,3ωreflection and on-axis hard X-rays)can ensure this *** demonstrated target positioning within several micrometers from the focus,ensuring over 80%of the ideal peak laser intensity *** approach is relatively fast(it requires 10±20 laser shots)and does not rely on the coincidence of low-power and high-power focal planes.

关键词： laser-plasma interaction precise target positioning spectroscopy ultra-high intensity X-rays

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The transition from backarc extension to Andean growth:Insights from geochronologic,sedimentologic,and structural studies of Mesozoic and Cenozoic sedimentary and volcanic rocks in south-central Chile(36°s)

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Geoscience Frontiers 2024年第5期15卷 93-117页

作者： Alfonso Encinas Nicolás Henríquez Daniel Castro Darío orts Diego Kietzmann Franco Iovino Paulo Vásquez Andrés Folguera Victor Valencia Facundo Fuentes Departamento de Ciencias de la Tierra Facultad de Ciencias QuímicasUniversidad de ConcepciónVíctor Lamas 1290Concepción 4030000Chile Universidad Nacional de Río Negro.Instituto de Investigación en Paleobiología y Geología.General Roca Río NegroArgentina Instituto de Investigación en Paleobiología y Geología(IIPG).CoNICET.Av.J.A.Roca 1242 8332 General RocaRío NegroArgentina Universidad de Buenos Aires Facultad de Ciencias Exactas y NaturalesDepartamento de Ciencias GeológicasCiudad UniversitariaPabellón IIIntendente Güiraldes 2160C1428EHA Ciudad Autónoma de Buenos AiresArgentina CoNICET-Universidad de Buenos Aires Instituto de Geociencias BásicasAmbientales y Aplicadas de Buenos Aires(IGeBA)Ciudad UniversitariaPabellón IIIntendente Güiraldes 2160C1428EHA Ciudad Autónoma de Buenos AiresArgentina Instituto de Estudios Andinos‘‘Don Pablo Groeber”(IDEAN) CONICET-Universidad de Buenos AiresBuenos AiresArgentina Facultad de Ciencias Exactas y Naturales Universidad de Buenos AiresBuenos AiresArgentina Washington state University School of the EnvironmentPullmanUSA yacimientos Petrolíferos Fiscales(yPF)s.A. Buenos AiresArgentina

Many studies propose a significant shift in the tectonic and paleogeographic evolution of the Andes in south-central Chile and Argentina during the Late *** has been proposed that the preceding Jurassic-Early Cretaceous extensional regime that resulted in a low-relief volcanic arc and the backarc Neuquén basin came to an end,giving way to shortening and Andean growth from the Late Cretaceous ***,there are disagreements regarding the timing and nature of this transition to Andean *** address these issues,we conducted geochronologic(U-Pb and^(40)Ar/&(39)Ar),sedimentologic,and structural studies on Mesozoic-Cenozoic sedimentary and volcanic rocks in the Río Maule area(Principal Cordillera,Chile,36°s).From our findings and prior analyses,we propose the following tectono-stratigraphic evolution of the region.(1)Marine deposition of the Tithonian-Hauterivian Baños del Flaco Formation took place in an extensional backarc basin.(2)After a~40 Myr hiatus,fluvial deposits of the Colimapu Formation and volcanic rocks of the Plan de los yeuques Formation accumulated during the *** the Colimapu Formation displays evidence of syndepositional shortening,the Plan de los yeuques Formation exhibits synextensional growth *** to other studies,our results suggest that the Chilean part of the Principal Cordillera was largely a zone of active deposition rather than an elevated fold-thrust belt during the Late *** propose that sedimentation occurred within a series of relatively stable intermontane subbasins generated by.s.ortening,followed by extension.(3)After a~20 Myr hiatus,middle Eocene to early Miocene(Lutetian-Aquitanian)accumulation of a thick succession of andesitic lavas and minor clastic sediments of the Abanico Formation occurred in an intraarc extensional basin.(4)Finally,major shortening and uplift of previously deposited Mesozoic-Cenozoic rocks took place throughout the *** phase constitu

关键词： Andes south-central Chile Backarc basin Foreland basin Fold-thrust belt

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