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Current and near-term advances in Earth observation for ecological applications

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Ecological Processes 2021年第1期10卷 1-57页

作者： Susan l.Ustin Elizabeth m.middleton John muir Institute of the Environment University of CaliforniaDavisCA 95616USA NASA/Goddard Space Flight Center(Emerita) GreenbeltMD 20771USA.

There is an unprecedented array of new satellite technologies with capabilities for advancing our understanding of ecological processes and the changing composition of the Earth’s biosphere at scales from local plots to the whole *** identified 48 instruments and 13 platforms with multiple instruments that are of broad interest to the environmental sciences that either collected data in the 2000s,were recently launched,or are planned for launch in this *** have restricted our review to instruments that primarily observe terrestrial landscapes or coastal margins and are available under free and open data *** focused on imagers that passively measure wavelengths in the reflected solar and emitted thermal *** suite of instruments we describe measure land surface characteristics,including land cover,but provide a more detailed monitoring of ecosystems,plant communities,and even some species then possible from historic *** newer instruments have potential to greatly improve our understanding of ecosystem functional relationships among plant traits like leaf mass area(lmA),total nitrogen content,and leaf area index(lAI).They provide new information on physiological processes related to photosynthesis,transpiration and respiration,and stress detection,including capabilities to measure key plant and soil biophysical *** include canopy and soil temperature and emissivity,chlorophyll fluorescence,and biogeochemical contents like photosynthetic pigments(e.g.,chlorophylls,carotenoids,and phycobiliproteins from cyanobacteria),water,cellulose,lignin,and nitrogen in foliar *** data will enable us to quantify and characterize various soil properties such as iron content,several types of soil clays,organic matter,and other *** of these satellites are in low Earth orbit(lEO),but we include a few in geostationary orbit(GEO)because of their potential to measure plant physiological traits over diurnal periods,impro

关键词： Terrestrial ecosystems Earth Observing Satellites Ecosystem processes Physiological functions multispectral Hyperspectral Thermal liDAR Radar imagers Biochemistry Soil properties Species mapping Change detection 3D canopy structure Topography

Crystal Growth of[Ca3Al(OH)6·12H2O]2·(SO4)3·2H2O (Ettringite) Studied Under microgravity Conditions

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Journal of Wuhan University of Technology(materials Science) 2020年第5期35卷 893-899页

作者： meier m R lEI l Rinkenburger A Plank J Technische Universitat miinchen Chair for Construction Chemistry85747 GarchingLichtenbergstrafie 4Germany

On parabolic flights,the growth of ettringite,[Ca3Al(OH)6·12H2O]2·(SO4)3·2H2O,a major reaction product of cement with water which forms instantaneously,was crystallized under microgravity conditions and *** the experiments,Ca(OH)2/Al2(SO4)3 solutions were combined and reacted for 10?s,followed by immediate filtration of the suspension and subsequent quenching with *** the ettringite crystals,the size,aspect ratios,quantity and morphology were determined and the results were compared with those from identical experiments performed under terrestric *** microgravity,generally smaller crystals (l-2.9 μm) precipitated in larger amount than under normal gravity (l-3.5 μm).The aspect ratios of the crystals grown under terrestric or microgravity condition were comparable at about *** is assumed that the reason for the smaller ettringite crystals is the absence of convection leading to more initial nuclei,but slower crystal growth which is diffusion ***,no preference relative to the ion transport to the different faces of the crystals *** results contribute to the understanding of the mineralization of inorganic salts under microgravity conditions for which hitherto only a handful of examples were reported.

关键词： crystallization ettringite microgravity morphology nucleation

Propagation of an electromagnetic soliton in an anisotropic biquadratic ferromagnetic medium

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Chinese Physics B 2013年第3期22卷 275-281页

作者： l.Kavitha m.Saravanan D.Gopi Department of Physics Periyar University The Abdus Salam International Centre for Theoretical Physics TriesteItaly Center for Nanoscience and Nanotechnology Periyar University Department of Chemistry Periyar University

Information storage technology based on anisotropic ferromagnets with sufficiently high magneto-optical effects has received much attention in recent ***-optical recording combines the merits of magnetic and optical *** investigate the magneto-optical effects on a biquadratic ferromagnet and show that the dynamics of the system are governed by a perturbed nonlinear Schro¨dinger *** evolutions of amplitude and velocity of the soliton are found to be time independent,thereby admitting the lossless propagation of the electromagnetic soliton in the medium,which may have potential applications in soliton based optical communication *** also exploit the role of perturbation,which has a significant impact on the propagation of an electromagnetic soliton.

关键词： solitons classical spin models maxwell equations nonlinear dynamics

Ultrafast synthesis and sintering of materials in a single running experiment approach by using electric fields

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Journal of Advanced Ceramics 2019年第2期8卷 265-277页

作者： lílian m.JESUS Ronaldo S.SIlVA Jean-Claude m’PEKO Sao Carlos Institute of Physics University of Sao Paulo(USP)P.O.Box:369CEP:13560-970 Sao CarlosSPBrazil Group of Advanced Ceramic materials Department of PhysicsFederal University of Sergipe(UFS)CEP:49100-000 Sao CristovaoSEBrazil Department of Physics Federal University of Sao Carlos(UFSCar)13560-905 Sao CarlosSPBrazil

Processing of materials in the form of ceramics normally involves several steps including calcination at a relatively low temperature for synthesis of the end-product powder and sintering at a high temperature for *** work we have been developing introduces a novel approach enabling synthesis plus sintering of materials in a single running experiment by using electric fields,ending with dense ceramics that display grains noticeably finer than in conventional *** new paradigm is fully illustrated with experiments conducted on amorphous CaCu3Ti4O12 precursor powder,shown to experience,on heating,crystallization through intermediate phases,followed by chemical reaction leading to synthesis of the end-product powder,plus densification depending on field *** processing time and furnace temperature are considerably reduced,demonstrating that enhanced synthesis and sintering rates applied under field *** results found in Bi2/3Cu3Ti4O12are also *** different factors that may contribute to this unique scenario,including Joule heating,defect generation,and reduction of free energy for nuclei formation promoted by the applied field,are briefly ***,the findings we bring here are exclusive as they show an exploitable way that allows rapid processing of materials with good control over particle and grain coarsening.

关键词： field-assisted processing synthesis sintering microstructure dielectric response

Expert perspectives on GIS use in Spanish geographic education

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International Journal of Digital Earth 2022年第1期15卷 1204-1218页

作者： I.J.Buzo-Sánchez C.mínguez m.l.De lázaro-Torres IES San Roque BadajozSpain Geography Department Universidad Complutense de MadridMadridSpain Geography Department UNEDMadridSpain

The emergence of new technological tools for territorial analysis,such as cloud-based GIS,or GIS viewers,compels us to closely examine its usefulness in geographic education. Specifically,it raises the professors and teachers’ questions: what to teach? how to teach? and what will students learn? This research responds to these three questions by interviewing Spanish experts who know how to use these tools to teach geography at university and secondary school levels. The Delphi technique was applied to achieve this,which established consensus and led to the following results from experts’ own experience: (1) that GIS help to understand territory in an experiential and non-memoristic way and (2) they enable the development of spatial thinking. This paper concludes that changes in methodologies and integrate technical knowledge into teacher training are needed.

关键词： Geography Delphi GIS competencies spatial thinking

Observations on the Formation of Ultrafine Ferrite Grain Size in Steels by Physical Simulation Routes

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Journal of materials Science & Technology 2003年第z1期19卷 112-114页

作者： l.X. Pan l.P. Karjalainen m. C. Somani University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland

Some observations are reported on the simulation of two thermomechanical routes to produce ultrafine ferrite grainsize in steels. One C-mn grade and Nb, Nb-Ti and Nb-high Ti bearing steels were used in the tests performed ona Gleeble simulator and a laboratory rolling mill. The routes included severe hot deformation of prior grain-refinedaustenite at the temperature close to Ar3 (DIF) and static recrystallization of fine-grained cold-rolled martensite(SRm). It was observed that the hot deformation induces the formation of ferrite above the Ar3 temperature of thesteel, but severe reductions are required for the complete transformation. Strain of 1.2 can result in about 70% offerrite with the grain size of about 1.4～2μm in all the studied steels. Similarly, in short annealing of cold-workedmartensite, the static recrystallization can also lead to a grain size of about 1.5 μm. The distribution of carbonvaries in the microstructures, carbon being in the second phase in the DIF route and in carbide particles in the SRmroute, which may have a significant influence on the mechanical properties and the thermal stability of ultrafine grainstructure.

关键词： Ultrafine grain size, Steels, Physical simulation, Strain-induced ferrite, Cold rolling and annealing

Isla San Pedro Nolasco as a late miocene intrusive record at the eastern margin of the Gulf of California:Insights from geological,geochemical and geochronological studies

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Geoscience Frontiers 2022年第3期13卷 100-114页

作者： l.A.Velderrain-Rojas J.R.Vidal-Solano l.m.Alva-Valdivia R.Vega-Granillo m.lópez-martinez Departamento de Geología División de Ciencias Exactas y NaturalesUniversidad de SonoraC.P.83000 HermosilloSonoraMexico laboratorio de Paleomagnetismo Instituto de GeofísicaUniversidad Nacional Autónoma de MéxicoCircuito de la Investigación CientíficaC.P.04510 MéxicoD.F.Mexico Departamento de Geología División de Ciencias de la TierraCentro de Investigación Científica y de Educación Superior de EnsenadaBaja CaliforniaMexico

Isla San Pedro Nolasco(ISPN)is a structural high bounded by inactive dextral oblique-slip faults in the east-central part of the Gulf of California rift zone and is composed of intrusive rocks not exposed on other Gulf of California *** we present the reconnaissance results from geological mapping,as well as first geochemical and geochronological data for the ISPN intrusive *** intrusive rocks compose a sheet-like body of intermediate and felsic composition intruded by an intermediate and acidic dike *** intrusive rocks(host and dikes)range in age from ca.9 ma to 10 ma(^(40)Ar/^(39)Ar)and show a hydrous ferromagnesian mineral association(amphibole and biotite)with a calc-alkalic and transitional *** hydrated mineralogical association has not been recognized in the coeval rocks along the onshore western margin of the North American plate(coastal Sonora).However,such hydrous mineralogical association is found in the coeval rift transitional volcanic rocks from the Baja California microplate at Santa Rosalía and Bahía de losÁngeles–Bahía de lasÁ*** ISPN continental block,at least 40 km long,has been pulled apart by transtensional faulting of the late miocene Gulf of California shear zone before the westward migration of the North America-Pacific plate boundary at ca.3–2 ***,ISPN became isolated as an island during the late miocene flooding of the Gulf of California seaway.

关键词： PAC-NAm plate boundary Gulf of California Intrusive rocks Isla San Pedro Nolasco

Stair and Step Soliton Solutions of the Integrable (2+1) and (3+1)-Dimensional Boiti-leon-manna-Pempinelli Equations

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Communications in Theoretical Physics 2012年第12期58卷 785-794页

作者： m.T. Darvishi m. Najafi l. Kavitha m. Venkatesh Department of mathematics Razi University Department of Physiology Faculty of Medicine Kermanshah University of Medical Sciences Department of Physics Periyar University Center for Nanoscience and Nanotechnology Periyar University

The multiple exp-function method is a new approach to obtain multiple wave solutions of nonlinear partial differential equations (NlPDEs). By this method one can obtain multi-soliton solutions of NlPDEs. In this paper, using computer algebra systems, we apply the multiple exp-function method to construct the exact multiple wave solutions of a (2+1)-dimensional Boiti-leon-manna-Pempinelli equation. Also, we extend the equation to a (3+1)-dimensional case and obtain some exact solutions for the new equation by applying the multiple exp-function method. By these applications, we obtain single-wave, double-wave and multi-wave solutions for these equations.

关键词： multiple exp-function method Boiti-leon-manna-Pempinelli equation exact solution multi-soliton solution

Physics design of 14 meV neutron generator facility at the Institute for Plasma Research

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Plasma Science and Technology 2023年第12期25卷 115-121页

作者： H l SWAmI S VAlA m RAJPUT m ABHANGI Ratnesh KUmAR A SAXENA Rajesh KUmAR Institute for Plasma Research Gandhinagar 382428India Homi Bhabha National Institute Training School ComplexMumbai 400094India

A high energy and high yield neutron source is a prime requirement for technological studies related to fusion reactor development. It provides a high-energy neutron environment for small-scale fusion reactor components research and testing such as tritium breeding, shielding, plasmafacing materials, reaction cross-section data study for fusion materials, etc. Along with ITER participation, the Institute of Plasma Research, India is developing an accelerator-based 14 meV neutron source with a yield of 10^(12)n s^(-1). The design of the source is based on the deuterium–tritium fusion reaction. The deuterium beam is accelerated and delivered to the tritium target to generate 14 meV neutrons. The deuterium beam energy and tritium availability in the tritium target are the base parameters of the accelerator-based neutron source design. The paper gives the physics design of the neutron generator facility of the Institute for Plasma Research. It covers the requirements, design basis, and physics parameters of the neutron generator. As per the analytical results generator can produce more than 1 × 10^(12)n s^(-1)with a 110 keV D^(+) ion beam of 10 mA and a minimum 5 Ci tritium target. However, the detailed simulation with the more realistic conditions of deuteron ion interaction with the tritium titanium target shows that the desired results cannot be achieved with 110 keV. The safe limit of the ion energy should be 300 keV as per the simulation. At 300 keV ion energy and 20 mA current, it reaches 1.6 × 10^(12)n s^(-1). moreover, it was found that to ensure sufficiently long operation time a tritium target of more than 20 Ci should be used. The scope of the neutron source is not limited to the fusion reactor research studies, it is extended to other areas such as medical radioisotopes research, semiconductor devices irradiations, and many more.

关键词： neutron generator neutronics accelerator physics design nuclear fusion