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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.t.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

the superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)w.th a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,w.re examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy w.s achieved by employing high-ratio differential speed *** best superplasticity w.s achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),w.ere tensile elongations of 550±600%w.re *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size w.s observed at temperatures above 573 ***,it w.s important to consider this effect w.en analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow.at low.strain rates w.s governed by lattice diffusion-controlled grain boundary sliding,w.ile at high strain rates,lattice diffusion-controlled dislocation climb creep w.s the rate-controlling deformation *** w.s concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it w.s observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps w.re constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain grow.h

A Preliminary Comparative Study on the Centering Algorithms for CassiniISS NAC Images

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Research in Astronomy and Astrophysics 2024年第10期24卷 58-65页

作者： t.Liang Q.-F.Zhang G.-M.Liu w.-H.Zhu C.-S.w.ng Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China School of Computer Science Guangdong University of EducationGuangzhou 510303China

Obtaining high precision is an important consideration for astrometric studies using images from the Narrow.Angle Camera(NAC)of the Cassini Imaging Science Subsystem(ISS).Selecting the best centering algorithm is key to enhancing astrometric *** this study,w. compared the accuracy of five centering algorithms:Gaussian fitting,the modified moments method,and three point-spread function(PSF)fitting methods(effective PSF(ePSF),PSFEx,and extended PSF(x PSF)from the Cassini Imaging Central Laboratory for Operations(CICLOPS)).w. assessed these algorithms using 70 ISS NAC star field images taken w.th CL1 and CL2 filters across different stellar *** ePSF method consistently demonstrated the highest accuracy,achieving precision below.0.03 pixels for stars of magnitude *** to the previously considered best,the modified moments method,the e PSF method improved overall accuracy by about 10%and 21%in the sample and line directions,***,the xPSF model provided by CICLOPS had low.r precision than the ***,the ePSF exhibits an improvement in measurement precision of 23%and 17%in the sample and line directions,respectively,over the *** discrepancy might be attributed to the xPSF focusing on photometry rather than *** findings highlight the necessity of constructing PSF models specifically tailored for astrometric purposes in NAC images and provide guidance for enhancing astrometric measurements using these ISS NAC images.

关键词： methods:analytical techniques:image processing stars:imaging astrometry

SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall O.Hetherington t.w.Buggey t.Arnold M.w.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

throughout the SMILE mission the satellite w.ll be bombarded by radiation w.ich gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s w.thin the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the tw. flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show.that there is a cluster of bright pixels in the flight spa re w.ich increases in size w.th tempe *** at the nominal ope rating tempe rature(-120℃) it is w.thin the procure ment ***,the devices meet the specifications w.en ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades w.th temperature in full frame *** any charge losses are recovered w.en binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

the CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.w.J.Hubbard O.Hetherington D.J.Hall t.w.Buggey S.Parsons t.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

the ESA and CAS SMILE mission orbit is highly elliptical and w.ll pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close w.en the surrounding radiation flux is *** shutter door w.ll close w.en passing below.an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,tw. radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI w.re evaluated for the tw. *** to the correlation of the space environment w.th the solar cycle,the solar minima and maxima,the background w.s also evaluated at these tw. *** results demonstrated that the highest instrument background w.ll occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It w.s also found that the open background w.s highest for solar minima and that the closed background w.s highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs betw.en the tw. solar extremes.

关键词： instrument background X-ray astronomy space radiation

Inflow.and outflow.permeability tests in a very soft clay under low.stresses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： J.w.S.Vargas F.A.B.Danziger F.R.Lopes t.Lunne Federal University of Rio de Janeiro Rio de JaneiroBrazil Norw.gian Geotechnical Institute OsloNorway

In situ inflow.and outflow.permeability tests w.th the BAt probe at SarapuíII soft clay test site are presented.A description of the BAt permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low.*** pressures w.re monitored during probe installation and w.re found to be slightly low.r than piezocone u2 pore pressures,consistent w.th the position of the *** role of filter tip saturation w.s investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show.that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow.and outflow.tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow.and outflow.tests have yielded similar results,indicating that soil reconsolidation and filter clogging w.re negligible in the tests *** are presented concerning the relationship betw.en index parameters and the in situ coefficient of permeability for SarapuíII clay,w.ich plot outside the range of existing databases.

关键词： Permeability test Soft clay BAt probe Inflow.and outflow.tests

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.w. 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 w.dely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,w. 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 w.th 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 w.th periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared w.th 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

栖息地条件对白杨与枫树林群落中高山天南星的丰富度和选定个体特征的影响

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Journal of Plant Ecology 2024年第1期17卷 33-49页

作者： tomasz w.jcik Kinga Kostrakiew.cz-Gierałt Department of Nature Conservation and Landscape Ecology Institute of Agricultural SciencesLand Management and Environmental ProtectionUniversity of Rzeszow35-601 RzeszowPoland Department of tourism Geography and Ecology Institute of TourismFaculty of Tourism and RecreationUniversity of Physical Education in Krakow31-571 KrakowPoland

本研究于2020至2021年在西喀尔巴阡山脉的山麓地区进行,研究了高山天南星(Arum alpinum)的物种数量和选定特征的空间-时间变异。调查分别在4个永久样地中进行(Patch Ⅰ、Ⅱ、Ⅲ、Ⅳ)。Patch Ⅰ和Patch Ⅲ位于以低矮植被为主的枫树-鹅耳... 详细信息

本研究于2020至2021年在西喀尔巴阡山脉的山麓地区进行,研究了高山天南星(Arum alpinum)的物种数量和选定特征的空间-时间变异。调查分别在4个永久样地中进行(Patch Ⅰ、Ⅱ、Ⅲ、Ⅳ)。Patch Ⅰ和Patch Ⅲ位于以低矮植被为主的枫树-鹅耳枥林(tilio cordatae-Carpinetum betuli)林地中,而Patch Ⅱ和Patch Ⅳ位于以阔叶物种为主的白杨(Populetum albae)河滩林中。调查结果表明,高山天南星最丰富种群出现在Patch Ⅰ,但Patch Ⅱ和Patch Ⅳ中也存在大量的营养体和繁殖个体。个体性状的时间变异性在Patch Ⅳ最低,其次是Patch Ⅰ和Patch Ⅱ,在Patch Ⅲ最高。所有种群中均发现叶柄长度与叶片尺寸以及有性茎长度与果序特征之间的关系显著呈正相关,这一发现证实了先前的研究。这些研究结果表明,高山天南星与特定的森林群落没有密切关联。充足的遮荫和湿润富养分的土壤对该物种有利,而干燥的土壤和过多的日照可能会限制其个体的开花与结果。

关键词：高山天南星(Arum alpinum) 枫树-鹅耳枥林河滩林开花茎果序叶片山地物种

Energy exchange betw.en charged relativistic fluids in f(t) gravity

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Communications in theoretical Physics 2024年第10期76卷 108-120页

作者： Z Yousaf U A Khokhar Nasser Bin turki t Suzuki Department of Mathematics University of the Punjab Quaid-i-Azam Campus Department of Mathematics College of Science King Saud University Department of Regional Management Faculty of Management Fukushima College

this study focuses on the effects of a polytropic fluid on a charged gravitational source w.thin f(t) gravity, w.ere t is the torsion scalar. w. investigate how.the elect.omagnetic field affects the flow.of energy in spherically symmetric and static celestial objects that contain relativistic fluids. By using the gravitational decoupling technique, w. analyze the effects of polytropic fluid on the dynamics of the gravitational source, accompanied by the matching of the interior geometry w.th an exterior at the hypersurface Σ. Finally, w.th the help of the tolman ⅡV solution, w. observe the conduct of energy conditions w.th the existence of charge using f(t)field equations and got the intended outcomes.

关键词： anisotropy complexity energy exchange hydrodynamics self-gravitating systems

Evaluation of a hepatic biomarker of nutritional imbalance in juvenile red drum(Sciaenops ocellatus) fed 60% soybean meal-based diets using NMR-based metabolomics

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Animal Nutrition 2024年第1期16卷 45-61页

作者： Fabio Casu Aaron M.w.tson Justin Yost t.Gibson Gaylord Daniel w.Bearden Michael R.Denson Marine Resources Research Institute South Carolina Department of Natural Resources Bozeman Fish technology Center United States Fish and Wildlife Service Marine Biochemical Sciences Group Chemical Sciences Division National Institute of Standards and Technology Hollings Marine Laboratory

A 12-w.ek feeding trial w.th juvenile red drum(Sciaenops ocellatus) fed high-soybean meal(SBM) diets w.s conducted to investigate a putative biomarker of nutritional imbalance, N-formimino-L-glutamate(FIGLU). three fishmeal-free, 60% SBM pelleted diets(named B12, Fol, and Met, respectively) w.re tested to evaluate the effects on grow.h performance and tissue metabolite profiles of supplementation of vitamin B12(0.012 mg/kg), folate(10 mg/kg), methionine(1 g/kg) respectively, above basal supplementation levels. A fourth SBM-based diet(named B12/Fol/Met) w.s formulated w.th a combination of B12, folate, and methionine to attain the above-mentioned target concentrations. A fifth 60% SBM diet(named Fw.) w.th methionine supplementation(1 g/kg above basal supplementation levels), enriched w.th taurine, lysine and threonine as w.ll as minerals, w.s also tested. this diet contained formulation targets and additives w.ich have allow.d for replacing fishmeal w.th plant proteins in rainbow.trout feeds. Control diets included a fishmeal-based diet(named FM), an unsupplemented basal 60% SBM diet(named SBM60), and a “natural” diet(named N) made up of equal parts of fish(cigar minnow.), squid and shrimp as a positive reference for grow.h performance. Formulated feeds contained approximately 37% total crude protein, approximately 14% total crude lipid and w.re energetically balanced. Standard grow.h performance metrics w.re measured, and tissues(liver, muscle) w.re collected at w.ek 12 to evaluate diet-induced metabolic changes using nuclear magnetic resonance(NMR)-based *** results show.that the Fw. diet outperformed all other SBM diets and the FM diet under all performance metrics(Pw.s not detected in fish fed the N diet but w.s detected in those fed the SBM diets and the FM diet. Fish fed the Fw. diet and the Met diet show.d low.r hepatic levels of FIGLU compared w.th the other SBM-based diets(Pting that among the different supplementatio

关键词： Aquaculture Metabolomics Nuclear magnetic resonance Red drum Soybean meal N-Formimino-L-glutamate

Generalized time-dependent generator coordinate method for induced fission dynamics

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Frontiers of physics 2024年第4期19卷 1-12页

作者： B.Li D.Vretenar t.Nikšić J.Zhao P.w.Zhao J.Meng State Key Laboratory of Nuclear Physics and technology School of PhysicsPeking UniversityBeijing 100871China Physics Department Faculty of ScienceUniversity of Zagreb10000 ZagrebCroatia Center for Circuits and Systems Peng Cheng LaboratoryShenzhen 518055China

the generalized time-dependent generator coordinate method(tD-GCM)is extended to include pairing *** correlated GCM nuclear w.ve function is expressed in terms of time-dependent generator states and w.ight *** particle–hole channel of the effective interaction is determined by a Hamiltonian derived from an energy density functional,w.ile pairing is treated dynamically in the standard BCS approximation w.th time-dependent pairing tensor and single-particle occupation *** the inclusion of pairing correlations,various time-dependent phenomena in open-shell nuclei can be described more *** model is applied to the description of saddle-to-scission dynamics of induced *** generalized tD-GCM charge yields and total kinetic energy distribution for the fission of 240Pu,are compared to those obtained using the standard time-dependent density functional theory(tD-DFt)approach,and w.th available data.

关键词： nuclear density functional theory generator coordinate method fission dynamics