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Composition and evolution of the continental crust:Retrospect and prospect

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Geoscience Frontiers 2022年第5期13卷 1-15页

作者： j.L.R.Touret m.Santosh j.m.Huizenga Institut de minéralogie Physique des MatériauxCosmochimieSorbonne Universités4 Place JussieuF-75005 ParisFrance 121 Rue de la Réunion 75020 ParisFrance School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaideSA 5005Australia Faculty of Environmental Sciences and Natural Resource management Norwegian University of Life SciencesP.O.Box 5003NO-1432ÅsNorway EGRU(Economic Geology Research Centre) James Cook UniversityTownsvilleQueensland 4811Australia Department of Geology University of JohannesburgPO Box 524Auckland Park 2006South Africa

Until the middle of the 20th century,the continental crust was considered to be dominantly *** hypothesis was revised after the Second World War when several new studies led to the realization that the continental crust is dominantly made of metamorphic *** rocks were emplaced at peak metamorphic conditions in domains,which can be defined by geophysical *** to medium-grade metamorphic rocks constitute the upper crust,granitic migmatites and intrusive granites occur in the middle crust,and the lower crust,situated between the Conrad and moho discontinuities,comprises charnockites and *** continental crust acquired its final structure during metamorphic episodes associated with mantle upwelling,which mostly occurred in supercontinents prior to their disruption,during which the base of the crust experienced ultrahigh temperatures(>1000℃,ultrahigh temperature granulite-facies metamorphism).Heat is provided by underplating of mantle-derived mafic magmas,as well as by a massive influx of low H_(2)O activity mantle fluids,***-density CO_(2) and highsalinity *** fluids are initially stored in ultrahigh temperature domains,and subsequently infiltrate the lower crust,where they generate anhydrous granulite mineral *** brines can reach upper crustal levels,possibly even the surface,along major shear zones,where granitoids are generated through brine streaming in addition to those formed by dehydration melting in upper crustal levels.

关键词： Brines CO_(2) Continental crust Granulite Lower crust

Amylopectin structure and crystallinity explains variation in digestion kinetics of starches across botanic sources in an in vitro pig model

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journal of Animal Science and Biotechnology 2019年第1期10卷 115-127页

作者： Bianca m.j.martens Walter j.j.Gerrits Erik m.A.m.Bruininx Henk A.Schols Laboratory of Food Chemistry Wageningen University and Research Animal Nutrition Group Wageningen University and Research Royal Agrifirm Group Agrifirm North West Europe

Background: Starch is the main source of energy in commonly used pig *** effects related to the extent of starch digestion,also several effects related to variation in digestion rate have recently been demonstrated in *** rates of starch digestion in animals and in in vitro models have been reported,depending on the botanic origin of *** from different botanic sources differ widely in structural and molecular *** the effect of starch properties on in vitro digestion kinetics based on existing literature is hampered by incomplete characterization of the starches,or by a selective choice of starches from a limited number of botanic *** research aimed to analyse the relationships between starch properties and in vitro digestion kinetics of pure starches isolated from a broad range of botanic origins,which are used in non-ruminant diets or have a potential to be used in the *** we studied starch digestion kinetics of potato,pea,corn,rice,barley,and wheat starches,and analysed the granule diameter,number of pores,type and amount of crystalline structure,amylose content and amylopectin side-chain length of all ***: multivariate analysis revealed strong correlations among starch properties,leading us to conclude that effects of most starch characteristics are strongly *** all analysed botanic sources,crystalline type and amylopectin chain length showed the strongest correlation with in vitro digestion *** percentages of A–type crystalline structure and amylopectin side chains of DP 6–24 both increased the rate of *** addition,within,but not across,(clusters of) botanic sources,a decrease in amylose content and increase in number of pores correlated positively with digestion ***: The type of crystalline structure and amylopectin chain length distribution of starch correlate significantly with digestion kinetics of starches ac

关键词： Amylopectin side chain distribution Amylose Granule diameter In vitro digestion kinetics Pores

Effects of thermal boundary conditions on the joule heating of electrolyte in a microchannel

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journal of Hydrodynamics 2016年第5期28卷 850-862页

作者： m. Y. ABDOLLAHZADEH jAmALABADI j. H. PARK m. m. RASHIDI j. m. CHEN Department of Ship Engineering Chabahar Maritime University Chabahar Iran Department of Aerospace and System Engineering Gyeongsang National University Jinju Korea . Engineering Faculty of Bu-Ali Sina University Hamedan Iran Department of mechanical and Nuclear Engineering Kansas State University Manhattan USA

joule heating effects on a slit microcharmel filled with electrolytes are comprehensively investigated with emphasis on the thermal boundary conditions. An accurate analytical expression is proposed for the electrical field and the temperature distributions due to joule heating are numerically obtained from the energy balance equation. The results show that a thermal design based on the average electric potential difference between electrodes can cause severe underestimation of joule heating. In addition, the parame- tric study of thermal boundary conditions gives us an insight into the best cooling scenario for microfluidic devices. Other significant thermal characteristics, including Nusselt number, thermophoretic force, and entropy generation, are discussed as well. This study will provide useful information for the optimization of a biomEmS device in relation to the thermal aspect.

关键词： microchannel electrolyte joule heating Nusselt number thermophoretic force entropy generation optimized thermaldesign

Selection of digital fabrication technique in the construction industry--A multi-criteria decision-making approach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： m.P.SALAImANImAGUDAm j.jAYAPRAKASH Department of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have provided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication method in terms of manufacturability and functionality requirements is a complex *** paper presents alternatives and criteria for selection of digital fabrication techniques by adopting the multi-criteria decision-making *** alternatives considered in the study are concrete three-dimensional(3D)printing,shotcrete,smart dynamic casting,material intrusion,mesh molding,injection concrete 3D printing,and thin forming *** criteria include formwork utilization,reinforcement incorporation,geometrical complexity,material enhancement,assembly complexity,surface finish,and build *** demonstrates different multi-criteria decision-making techniques,with both subjective and objective weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcement incorporation,build area,and geometrical complexity play a pivotal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D printing emerged as the best performer,however the shotcrete and mesh molding techniques in the second and third positions.

关键词： digital fabrication multicriteria decision-making concrete 3D printing

Design and Robust Performance Evaluation of a Fractional Order PID Controller Applied to a DC motor

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IEEE/CAA journal of Automatica Sinica 2017年第2期4卷 304-314页

作者： j.Viola L.Angel j.m.Sebastian Universidad Pontificia Bolivariana Universidad Politecnica de madrid Centre for Automation and Robotics (CAR) UPM-CSIC

This paper proposes a methodology for the quantitative robustness evaluation of PID controllers employed in a DC motor. The robustness analysis is performed employing a 2~3 factorial experimental design for a fractional order proportional integral and derivative controller(FOPID), integer order proportional integral and derivative controller(IOPID)and the Skogestad internal model control controller(SImC). The factors assumed in experiment are the presence of random noise,external disturbances in the system input and variable load. As output variables, the experimental design employs the system step response and the controller action. Practical implementation of FOPID and IOPID controllers uses the mATLAB stateflow toolbox and a NI data acquisition system. Results of the robustness analysis show that the FOPID controller has a better performance and robust stability against the experiment factors.

关键词： Factorial experimental design fractional-order PID controller robustness analysis SImC PID controller

High-temperature granulites and supercontinents

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Geoscience Frontiers 2016年第1期7卷 101-113页

作者： j.L.R.Touret m.Santosh j.m.Huizenga Institut de mineralogie Physique des MateriauxCosmochimie(IMPMC)Sorbonne Universites et UPMC Univ Paris 06UMR CNRS 7590Museum National d'Histoire NaturelleIRD UMR 2064 Place JussieuF-FS005 ParisFrance School of the Earth Sciences and Resources China University of Geosciences(Beijing)29 Xueyuan RoadBeijing 100083China Economic Geology Research Institute(EGRU) College of ScienceTechnology and EngineeringJames Cook UniversityTownsvilleQueensland4811Australia Unit for Environmental Sciences and management North-West UniversityPrivate Bag X60012520South Africa

The formation of continents involves a combination of magmatic and metamorphic processes. These processes become indistinguishable at the crust-mantle interface, where the pressure-temperature（P-T）conditions of（ultra） high-temperature granulites and magmatic rocks are similar. Continents grow laterally, by magmatic activity above oceanic subduction zones（high-pressure metamorphic setting）, and vertically by accumulation of mantle-derived magmas at the base of the crust（high-temperature metamorphic setting）. Both events are separated from each other in time; the vertical accretion postdating lateral growth by several tens of millions of years. Fluid inclusion data indicate that during the high-temperature metamorphic episode the granulite lower crust is invaded by large amounts of low H2O-activity fluids including high-density CO2 and concentrated saline solutions（brines）. These fluids are expelled from the lower crust to higher crustal levels at the end of the high-grade metamorphic event. The final amalgamation of supercontinents corresponds to episodes of ultra-high temperature metamorphism involving large-scale accumulation of these low-water activity fluids in the lower *** accumulation causes tectonic instability, which together with the heat input from the subcontinental lithospheric mantle, leads to the disruption of supercontinents. Thus, the fragmentation of a supercontinent is already programmed at the time of its amalgamation.

关键词： Continents Supercontinents magmatism and metamorphism Fluids Tectonics

Synthesis and electronic properties of expanded 5-(hetero)arylthien-2-yl substituted 3-ethynyl quinoxalines with AIE characteristics

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Science China Chemistry 2018年第8期61卷 909-924页

作者： Franziska K.merkt Thomas j.j.müller Institute of Organic Chemistry and macromolecular Chemistry Heinrich Heine University Düsseldorf

Expanded 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes with variable substitution pattern on the peripheral thiophene ring were synthesized in moderate to very good yields by Suzuki and Buchwald-Hartwig coupling of the corresponding brominated 3-ethynyl quinoxalines. Dumbbell-shaped bis(thienyl 3-ethynyl quinoxalines) are also accessible by the Suzuki protocol. The photophysical properties were investigated by UV and fluorescence spectroscopy. most of the obtained compounds display fluorescence in solution and some of them also in the solid state. Additionally, tuning of the emission color of the quinoxaline based chromophores can be conveniently accomplished by the remote substituent group. The determined absorption and emission maximum as well as the Stokes shifts strongly correlate with Hammett σp+parameters. Besides,photophysical properties of selected derivatives in the solid state, biphasic solutions, and PmmA films, along with their relationships, are comparatively investigated. moreover, two 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes are aggregation induced emission(AIE) chromophores indicated by restriction of molecular motions. A covalently restricted 3-ethynyl quinoxaline supports that the inhibition of molecular rotation is responsible for the significant enhancement of fluorescence in acetonitrile/water mixtures.

关键词： absorption aggregation induced emission cross-coupling fluorescence heterocycles palladium

methanol oxidation in acidic and alkaline electrolytes using PtRuIn/C electrocatalysts prepared by borohydride reduction process

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燃料化学学报 2018年第12期46卷 1462-1471页

作者： Santos m.C.L. Nandenha j. Ayoub j.m.S. Assumpao m.H.m.T. Neto A.O. Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN-SPAv.Prof.Lineu Prestes2242 Cidade UniversitáriaCEP 05508-000Sao PauloSPBrazil Universidade Federal de Sao Carlos UFSCar Campus Lagoa do Sino Rodovia Lauri Simoes de Barros Km 12 CEP 18290-000-Buri-Sao Paulo SP Brazil

PtRuIn/C electrocatalysts( 20% metal loading by weight) were prepared by sodium borohydride reduction process using H_2PtCl6·6H_2O,RuCl_3·xH_2O and InCl_3·xH_2O as metal sources,borohydride as reducing agent and Carbon Vulcan XC72 as support. The synthetized PtRuIn/C electrocatalysts were characterized by X-ray diffraction( XRD),energy dispersive analysis( EDX),transmission electron microscopy( TEm),cyclic voltammetry( CV),chronoamperommetry( CA) and polarization curves in alkaline and acidic electrolytes( single cell experiments). The XRD patterns showPtpeaks are attributed to the face-centered cubic( fcc) structure,and a shift of Pt( fcc) peaks indicates that Ru or In is incorporated into Ptlattice. TEmmicrographs showmetal nanoparticles with an average nanoparticle size between 2.7 and 3.5 nm. methanol oxidation in acidic and alkaline electrolytes was investigated at room temperature,by CV and CA. PtRu/C( 50 ∶ 50) shows the highest activity among all electrocatalysts in study considering methanol oxidation for acidic and alkaline electrolyte. Polarization curves at 80 ℃ showPtRuIn/C( 50 ∶ 25 ∶ 25)with superior performance for methanol oxidation,when compared to Pt/C,PtIn/C and PtRu/C for both electrolytes. The best performance obtained by PtRuIn/C( 50 ∶ 25 ∶ 25) in real conditions could be associated with the increased kinetics reaction and/or with the occurrence simultaneously of the bifunctional mechanism and electronic effect resulting from the presence of Ptalloy.

关键词： borohydride reduction process PtRuIn/C electrocatalysts methanol oxidation acidic and alkaline electrolytes polarization curves

Inelastic Cotunneling Current and Shot Noise of an Interacting Quantum Dot with Ferromagnetic Correlations

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Communications in Theoretical Physics 2007年第12期48卷 1099-1106页

作者： Norman j.m.Horing Department of Physics and Engineering Physics Stevens Institute of TechnologyHobokenNew Jersey 07030USA

We explore inelastic cotunneling through a strongly Coulomb-blockaded quantum dot attached to twoferromagnetic leads in the weak coupling limit using a generic quantum Langevin equation *** first developa B1och-type equation microscopically to describe the cotunneling-induced spin relaxation dynamics,and then developexplicit analytical expressions for the local magnetization,current,and its *** this basis,we predict a novelzero-bias anomaly of the differential conductance in the absence of a magnetic field for the anti-parallel configuration,and asymmetric peak splitting in a magnetic ***,for the same system with large polarization,we find a negativezero-frequency differential shot noise in the low positive bias-voltage region. All these effects are ascribed to rapidspin-reversal due to underlying spin-flip cotunneling.

关键词： quantum dot spin polarized tunneling cotunneling