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Recent advancements in thermal conductivity of magnesium alloys

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journal of Magnesium and Alloys 2024年第5期12卷 1687-1708页

作者： Hao Lv jun Tan Qian Yuan Fanglei Wang Yunxuan Zhou Quan Dong Aitao Tang jürgen eckert Bin jiang Fusheng Pan National engineering Research Center for Magnesium Alloys College of Materials Science and EngineeringChongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China Department of Materials Science Chair of Materials PhysicsMontanuniversität LeobenJahnstraße 12Leoben A-8700Austria erich Schmid Institute of Materials Science Austrian Academy of SciencesJahnstraße 12Leoben A-8700Austria

As highly integrated circuits continue to advance,accompanied by a growing demand for energy efficiency and weight reduction,materials are confronted with mounting challenges pertaining to thermal conductivity and lightweight *** virtue of numerous intrinsic mechanisms,as a result,the thermal conductivity and mechanical properties of the Mg alloys are often inversely related,which becomes a bottleneck limiting the application of Mg *** on several effective modification methods to improve the thermal conductivity of Mg alloys,this paper describes the law of how they affect the mechanical properties,and clearly indicates that peak aging treatment is one of the best ways to simultaneously enhance an alloy's thermal conductivity and mechanical *** the most frequently used Mg alloy,cast alloys exhibit substantial potential for achieving high thermal ***,recent reports indicate that hot deformation can significantly improve the mechanical properties while maintaining,and potentially slightly enhancing,the alloy's thermal *** presents a meaningful way to develop Mg alloys for applications in the field of small-volume heat dissipation components that require high *** comprehensive review begins by outlining standard testing and prediction methods,followed by the theoretical models used to predict thermal conductivity,and then explores the primary influencing factors affecting thermal *** review summarizes the current development status of Mg alloys,focusing on the quest for alloys that offer both high thermal conductivity and high *** concludes by providing insights into forthcoming prospects and challenges within this field.

关键词： Mg alloy Thermal conductivity Mechanical properties Solute atom Second phase

Optimization and control of synchrotron emission in ultraintense laser–solid interactions using machine learning – CORRIGeNDUM

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High Power Laser Science and engineering 2024年第1期12卷 116-116页

作者： j.Goodman M.King e.j.Dolier R.Wilson R.j.Gray P.McKenna 不详

Due to an isolated error in the 3D simulation parameters,the laser energy and intensity(calculated using the energy)values were incorrectly stated as 10.9 j and 3×10^(22) W cm^(−2),respectively,in Sections 3.3,7 and *** correct values are 39.8 j and 1.1×10^(23) W cm^(−2).Similarly,the values stated for the higher energy case,109 j and 3×10^(23) W cm^(−2) in Section 7,should be 398 j and 1.1×10^(24) W cm^(−2),respectively.

关键词： Bayesian optimization gamma rays laser-solid interactions machine learning radiation reaction

experimental measurements of gamma-photon production and estimation of electron/positron production on the PeTAL laser facility

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Matter and Radiation at extremes 2024年第5期9卷 32-47页

作者： F.Brun L.Ribotte G.Boutoux X.Davoine P.e.Masson-Laborde Y.Sentoku N.Iwata N.Blanchot D.Batani I.Lantuéjoul L.Lecherbourg B.Rosse C.Rousseaux B.Vauzour D.Raffestin e.D’Humières X.Ribeyre Centre Lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance CeA DAMCESTAF-33116 Le BarpFrance CeA DAMDIFF-91297 ArpajonFrance CeA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of Laser engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity PeTawatt Aquitaine Laser(PeTAL)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 j,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SeSAMe(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and L-shells were clearly detected by a photon spectrometer called SPeCTIX(Spectromètre PetalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chambre-rayonnement X),a bremsstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was *** simulations model the preplasma generated at the front of the target by the PeTAL laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enabled reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process. positron hypothesis

Hybrid silicon modulators

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Chinese Optics Letters 2009年第4期7卷 280-285页

作者： j.e.Bowers Department of electrical and Computer engineering University of California Santa Barbara

A number of active elements have been demonstrated using the hybrid silicon evanescent platform, including lasers, amplifiers, and detectors. In this letter, two types of hybrid silicon modulators, flflfilling the building blocks in optical communication on this platform, are presented. A hybrid silicon electroabsorp- tion modulator, suitable for high speed interconnects, with 10-dB extinction ratio at -5 V and 16-GHz modulation bandwidth is demonstrated. In addition, a hybrid silicon Mach-Zehnder modulator utilizing carrier depletion in multiple quantum wells is proved with 2 *** voltage-length product, 150-nm optical bandwidth, and a large signal modulation up to 10 Gb/s.

关键词： Bandwidth electroabsorption modulators Modulation Modulators Optical communication Quantum well lasers Semiconducting indium compounds Semiconductor quantum wells Silicon Silicon detectors

Approximate ballistics formulas for spherical pellets in free flight

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Defence Technology（防务技术） 2018年第1期14卷 1-11页

作者： e.j.Allen Department of Mathematics and Statistics Texas Tech University

The ballistics equations for spherical pellets in free flight are simplified through appropriate scaling of the pellet velocity and pellet distance. Two different drag coefficient curves are averaged to yield a single curve applicable to shot pellets and round balls. The resulting S-shaped drag coefficient curve is approximated by three straight-line segments. The scaled ballistics equations are then solved exactly and simple formulas are found for the velocity and flight time with respect to trajectory distance. The formulas are applicable to spherical shot pellets and round balls of any composition under any atmospheric conditions. The formulas are amenable to quick and easy computation and may also serve as an aid in understanding and comparing black-box ballistics calculators. For shotshell ballistics, an important assumption in the present investigation is that the pellets are moving as single, free spheres and not as a dense cloud or in a shot column, in particular, the pellets are not interacting during flight. Therefore, the formulas are most appropriate for single round balls, for large shot sizes, and for pellets of small shot size fired from open chokes. The formulas are clear and accessible, and can be implemented by military or law enforcement personnel as well as hunters and shooters. This work differs from previous investigations in that accurate ballistics formulas are derived for spherical projectiles of shotguns and muzzleloaders using realistic drag coefficients.

关键词： Ballistics Sphere Drag Shotgun Muzzleloader Nondimensionalization

Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

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journal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FeRNANDeS Letícia RAMOS Dario C.PAIVA jéssica CUNHA-BLUM Vanessa Matos GOMeS Daniel NeGReIROS ecologia evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge Center for Biodiversity 31270-901Belo HorizonteMGBrazil Department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de estudo das Relações Solo-Planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the *** environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low *** determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological *** proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic *** described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and *** three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia *** distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt *** provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local *** to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem *** study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： Canga ecological restoration extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

Bulking Up the Bay-Position Substituents enables enhanced Selectivity of C_(s)‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： Nina F.Farac Alan j.Lough Timothy P.Bender Department of Chemical engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of Materials Science and engineering University of TorontoTorontoOntario M5S 3E4Canada Department of Mechanical and Industrial engineering University of TorontoTorontoOntario M5S 3G8Canada

The precise synthesis of subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of functional ***,selective,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Nc_(p))s,are desirable for this purpose yet synthetically challenging due to random mixtures of C_(s-),C_(3v-),and,in some cases,C_(1)-symmetric compounds that form during traditional statistical mixed ***,we addressed this issue by developing a sterically driven mixed cyclotrimerization with enhanced selectivity for the targeted C_(s)-symmetric hybrid and complete suppression of sterically crowded macrocyclic *** process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of bay-position phenylated Ph_(2)-(R_(p))_(8)Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=Cl or F)in their peripheral isoindole *** selectivity ranged between 59 and 72%with remarkable yields,significantly higher than that of conventional mixed *** findings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle ***,the incorporation of unfused phenyl groups and halogen atoms into the hybrid framework resulted in fine-tuned optical,structural,electronic,and electrochemical *** straightforward approach achieved improved selectivity and controlled narrowing of the product distribution,affording the efficient synthesis of structurally sophisticated Bsub(Pc_(2)-Nc_(1))*** then expands the library of 3-dimensionalπ-extended macrocycles for use in a range of applications,such as in optoelectronic devices with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorption material properties

Opposite latitudinal gradients for species richness and phylogenetic diversity of endemic snakes in the Atlantic Forest

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Current Zoology 2024年第4期70卷 522-530页

作者： joséThales da Motta Portillo josuéAnderson Rēgo Azevedo Fausto erritto Barbo Ricardo j.Sawaya Programa de Pos-Graduacao em Biologia Animal Instituto de BiocienciasLetras e Ciencias ExatasUniversidade Estadual Paulista"Julio de Mesquita Filho"Rua Cristovao Colombo2265Sao Josédo Rio PretoSao Paulo 15054-000Brazil Programa de Colecoes Cientificas Biologicas Coordenagao de BiodiversidadeInstituto Nacional de Pesquisas da AmazoniaAvenida AndréAraujo2936ManausAmazonas 69067-375Brazil Gothenburg Global Biodiversity Centre University of GothenburgBox 461GothenburgVastra Gotaland SE-40530Sweden Instituto Federal de educacao Ciencia e Tecnologia de Minas GeraisRodovia Machado-Paraguacukm 3MachadoMinas Gerais 37750-000Rraizil Centro de Ciencias Naturais e Humanas UniversidadeFederaldo ABCRua Arcturus03Sao Bernardo do CampoSao Paulo09606-070Brazil

The decrease in species richness toward higher latitudes is an expected biogeographical *** pattern could be related to particular envi-ronmental constraints and the evolutionary history of ***,species richness does not fully represent the evolutionary history of the clades behind their *** diversity better clarifies the role of historical factors in biogeographical *** analyzed envi-ronmental and historical drivers related to latitudinal variation in species richness and phylogenetic diversity of Atlantic Forest endemic *** implemented species distribution models,from voucherbased locality points,to map the snake ranges and *** used generalized additive mixed models to evaluate the relationships among the diversity metrics and area,topographical roughness,and past climate change velocity since the Last Maximum Glacial in the Atlantic Forest latitudinal *** to the expected general pattern,species richness was higher toward higher latitudes,being positively related to past climatic *** richness also increased with total area and higher topographical *** diversity,on the other hand,showed opposite relationships related to the same *** diversity increased with lower climatic stability in lower ***,dimensions of diversity were affected in different ways by historical and environmental constraints in this unique and threatened biodiversity hotspot.

关键词： biodiversity latitudinal gradient neotropical region phylogenetic diversity serpents species richness.

Further investigation on the fusion of ^(6)Li with ^(209)Bi target at near-barrier energies

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Chinese Physics C 2024年第7期48卷 106-117页

作者：张高龙焦振威张广鑫 M.R.Cortes 胡世鹏钱建强 D.Mengoni 屈卫卫李聪博郑云张焕乔孙慧斌王楠张春雷 j.j.Valiente-Dobón D.Testov M.Mazzocco A.Gozzelino C.Parascandolo D.Pierroutsakou M.La Commara A.Goasduff D.Bazzacco D.R.Napoli F.Galtarossa F.Recchia A.Illana S.Bakes I.Zanon S.Aydin G.de Angelis M.Siciliano R.Menegazzo S.M.Lenzi j.L.Ferreira j.Rangel Serkan Akkoyun L.F.Canto j.Lubian School of Physics Beihang UniversityBeijing 100191China Sino-French Institute of Nuclear engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Instituto de Física Universidade Federal Fluminense24210-340NiteróiRio de JaneiroBrazil Institute for Advanced Study in Nuclear energy&Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Research and Manufacture of High Purity Germanium Materials and Fetectors Shenzhen UniversityShenzhen 518060China INFN Sezione di PadovaPadovaItaly Dipartimento di fisica Astronomia dell'Universita di padova PadovaItaly State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China China Institute of Atomic energy Beijing 102413China The Key Laboratory of Beam Technology and Material Modification of Ministry of education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China INFN Laboratori Nazionali di LegnaroI-35020 LegnaroItaly INFN Sezione di NapoliI-80126 NapoliItaly Dipartimento di Farmacia Universitàdi Napoli"Federico II"I-80131 NapoliItaly Department of Natural and Mathematical Sciences Faculty of EngineeringTarsus University33480 MersinTurkiye Physics Division Argonne National LaboratoryLemont-ILUSA Departamento de Matemaética Física e Computaç˜ao Universidade do Estado do Rio de JaneiroFaculdade de Tecnologia27537-000ResendeRio de JaneiroBrazil Department of Physics Sivas Cumhuriyet UniversitySivasTurkey Instituto de Física Universidade Federal do Rio de JaneiroCP 6852821941-972Rio de JaneiroBrazil

The complete and incomplete fusion cross sections for ^(6)Li+^(209)Bi were measured using the in-beamγ-ray method around the Coulomb *** cross sections of(deuteron captured)incomplete fusion(ICF)products were re-quantified experimentally for this reaction *** results reveal that the ICF cross section is equivalent to that of complete fusion(CF)above the Coulomb barrier and dominant near or below the Coulomb barrier.A theoretical calculation based on the continuum discretized coupled channel(CDCC)method was performed for the aforementioned CF and ICF cross sections;the result is consistent with the *** universal fusion function(UFF)was also compared with the measured CF cross section for different barrier parameters,demonstrating that the CF suppression factor is significantly influenced by the choice of potential,which can reflect both dynamic and static effects of breakup on the fusion process.

关键词： cross section incomplete fusion suppression factor weakly bound nuclei