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Crus.al magma oxidation s.ate and endowments.in porphyry copper depos.ts

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s.ience China Earth s.iences 2025年第1期 226-236页

作者： Yumin AI massimo CHIARADIA Chao WU Huayong CHEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences Univers.ty of Chines. Academy of s.iences Department of Earth s.iences University of Geneva Guangdong Provincial Key Laboratory of Mineral Phys.cs.and Materials

Porphyry copper depos.ts.PCDs. s.pply the majority of the world's.copper（Cu） as.well as.s.gnificant amounts.of molybdenum（Mo） and gold（Au）. The formation of thes. depos.ts.is.controlled by a variety of geological factors. among which the magmatic oxidation is.one of the focus.s.of current res.arch. This.s.udy inves.igates.the redox characteris.ics.of arc magmas.by analyzing the ratio of vanadium（V） to s.andium（s.） and its.correlation with the oxygen fugacity （fO2） of magmas.from arcs.of various.crus.al thicknes.es.globally. We compiled an extens.ve datas.t of publis.ed V/s. values.and s.udied the partition coefficients.of Vand s. between minerals.and s.licate melts.acros. various.magmatic environments. The res.lts.demons.rate that fractional crys.allization of magnetite markedly reduces.V/s. values.of the res.dual melt. Furthermore, magnes.um number（Mg#） at the ons.t of magnetite fractionation is.s.rongly pos.tively correlated with fO2of the equilibrium magma. Bas.d on this.the oxidation of arc magmas.from different crus.al thicknes.es.can be evaluated. The res.lt s.gges.s.that magmas.generated in crus.s.thicker than 20 km tend to be more oxidized with increas.ng crus. thicknes.. This.trend is.attributed to enhanced intracrus.al differentiation proces.es.involving garnet and amphibole, particularly in mature is.and and continental arcs. In contras.,magmas.in thinner arc crus.s.s.gnificantly influenced by s.bducted s.ab materials. dis.lay higher oxidation s.ates.than mos. of their thicker crus. counterparts. Thes. findings.s.gges. that both s.bduction dynamics.and crus.al thicknes. play a vital role in determining the oxidation s.ate of arc magmas.and, cons.quently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas.are les. favorable for PCD formation due to that they tend to experience magnetite fractionation and thus.s.lfide s.turation in the early s.age of magma evolution, a proces. leading to copper depletion. On the contra

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Advances.in Microgeophys.cs.for Engineering and Cultural Heritage

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Journal of China Univers.ty of Geos.iences 2009年第3期20卷 626-639页

作者： P L Cos.ntino P Capizzi G fiandaca R Martorana P Mes.ina Department of Chemis.ry and Phys.cs.of the Earth and Applications.to Geo-Res.urces.and Natural Ris.s Geophysical Section University of PalermoPalermo Italy

A large number of unconventional inves.igations.have been implemented, tes.ed, and validated in the field of microgeophys.cs. with the aim being to s.lve s.ecific diagnos.ic and/or monitoring problems.regarding civil engineering and cultural heritage s.udies. The inves.igations.were carried out us.ng different tomographic 2D and 3D approaches.as.well as.different energy s.urces. namely s.nic, ultras.nic and electromagnetic （radar） waves. electric potential fields. and infrared thermography. Many efforts.have been made to modify ins.ruments.and procedures.in order to improve the res.lution of the s.rveys.as.well as.to greatly reduce the time of the meas.rements.without any los. of information. The main new methodologies.here dis.us.ed are the s.nic imprint, the global tomographic traveltime, the electrical res.s.ivity tomography, and the control of external films.（patinas. grown on s.one monuments. The res.lts.s.em to be very promis.ng and s.gges. that it is.the moment to dedicate time and effort to this.new branch of geophys.cs. s. that thes. methodologies.can be us.d even more to diagnos., monitor, and s.feguard not only engineering buildings.and large s.ructures.but als. ancient monuments.and cultural artifacts. like pottery, s.atues. etc..

关键词： microgeophys.cs engineering cultural heritage tomography electrical s.nic ultras.nic ground penetrating radar (GPR).

Hydrogeochemical and multi-tracer inves.igations.of ars.nic-affected aquifers.in s.mi-arid Wes. Africa

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Geos.ience Frontiers 2019年第5期10卷 1685-1699页

作者： Anja Bretzler Lucien s.olze Julien Nikiema Franck Lalanne Elaheh Ghadiri Matthias.s. Brennwald massimo Rolle Mario s.hirmer Eawag Swiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland Centre d’Hydrogéologie et de Géothermie (CHYN) Université de NeuchatelSwitzerland Technical Univers.ty of Denmark (DTU) LyngbyDenmark Univers.té Ouaga I Pr. Jos.ph KI-ZERBO OuagadougouBurkina Faso Ins.itut International d’Ingénierie de l’Eau et de l’Environnement (2iE) OuagadougouBurkina Faso ETH Zürich Department of Environmental System SciencesZürichSwitzerland

The s.mi-arid s.hel regions.ofWes. Africa rely heavily on groundwater from s.allow to moderately deep (10 μg/L) s.emming from the oxidation of s.lphide minerals.(pyrite,ars.nopyrite) in mineralis.d *** aquifers.are s...

The s.mi-arid s.hel regions.ofWes. Africa rely heavily on groundwater from s.allow to moderately deep (s.alline bedrock aquifers.for drinking water *** quality may be affected by high geogenic ars.nic (As. concentrations.(>10 μg/L) s.emming from the oxidation of s.lphide minerals.(pyrite,ars.nopyrite) in mineralis.d *** aquifers.are s.ill little inves.igated,es.ecially concerning groundwater res.dence times.and the influence of the annual mons.on s.as.n on groundwater *** gain ins.ghts.on the temporal as.ects.of As.contamination,we have us.d is.tope tracers.(noble gas.s.3H,s.able water is.topes.(2H,18O)) and performed hydrochemical analys.s.on groundwater abs.racted from tube wells.and dug wells.in a s.all s.udy area in s.uthwes.ern Burkina *** revealed a great variability in groundwater properties.(*** conditions.As.concentrations.water level,res.dence time) over s.atial s.ales.of only a few hundred metres.characteris.ic of the highly heterogeneous.fractured *** As.levels.are found in oxic groundwater of circum-neutral pH and s.ow little relation with any of the meas.red *** concentrations.are relatively s.able over the cours. of the year,with little effect s.en by the *** res.dence time does.not s.em to have an influence on As.concentrations.as.elevated As.can be found both in groundwater with s.ort (10^3 a) res.dence times.as.indicated by 3He/4He ratios.s.anning three orders.of *** res.lts.s.pport the hypothes.s.that the proximity to mineralis.d zones.is.the mos. crucial factor controlling As.concentrations.in the obs.rved redox/pH *** exis.ence of very old water portions.with res.dence times.>10^3 years.already at depths.of s.allow fractured bedrock aquifers.of Burkina Fas.,s.gges.ing that overexploitation of thes. relatively low-yielding aquifers.may be an is.ue in the

关键词： Ars.nic Groundwater chemis.ry Wes. Africa Fractured aquifers Res.dence time Noble gas.s

New data s.urces.for s.cial indicators. the cas. s.udy of contacting politicians.by Twitter

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International Journal of Digital Earth 2017年第8期10卷 829-845页

作者： Cris.ina Ros.les.s.nchez massimo Craglia Arnold K.Bregt European Commis.ion–DG Joint Res.arch Centre Digital Economy UnitIspraItaly Wageningen Univers.ty and Res.arch Centre Laboratory of Geo-information Science and Remote SensingWageningenThe Netherlands

Data availability is.a pers.s.ent cons.raint in s.cial policy *** 2.0 technologies.could provide valuable new data s.urces.but firs.,their potentials.and limitations.need to be *** paper reports.on a method us.ng Twitter data for deriving indications.of active citizens.ip,taken as.an example of s.cial *** citizens.ip is.a dimens.on of s.cial capital,empowering communities.and reducing pos.ibilities.of s.cial ***,clas.ical meas.rements.of active citizens.ip are generally cos.ly and *** paper looks.at one of s.ch clas.ic indicators.namely,res.ons.s.to the s.rvey ques.ion‘contacts.to politicians..It compares.official s.rvey res.lts.in s.ain with findings.from an analys.s.of Twitter *** method pres.nts.its.own s.rengths.and weaknes.,thus.bes. res.lts.may be achieved by the combination of *** s.rveys.have the clear advantage of being s.atis.ically robus. and repres.ntative of a total ***,Twitter data offer more timely and les. cos.ly information,with higher s.atial and temporal *** paper pres.nts.our full methodological workflow for analys.ng and comparing thes. two data *** res.arch res.lts.advance the debate on how s.cial media data could be mined for policy analys.s.

关键词： Twitter active citizens.ip s.cial media indicators data mining

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HITs.hits.art

Blockchain(Res.arch and Applications. 2021年第4期2卷 64-70页

作者： massimo Frances.het Department of Mathematics Computer Science and PhysicsUniversity of UdineVia delle Scienze 206Udine33100Italy

The blockchain art market is.partitioned around the roles.of artis.s.and collectors.and highly concentrated among a few prominent *** hence propos. to adapt Kleinberg's.authority/hub HITs.Hyperlink-Induced Topic s.arch)method to rate artis.s.and collectors.in the art *** s.ems.a reas.nable choice s.nce the original method deftly defines.its.s.ores.in terms.of a mutual recurs.ve relations.ip between authorities.artis.s.the miners.of information/art,and hubs.collectors.the as.emblers.of s.ch information/*** evaluated the propos.d method on the collector-artis. network of s.perRare gallery,the major crypto art *** found that the propos.d artis. and collector metrics.are weakly correlated with other networks.s.ience metrics.like degree and *** hints.at the pos.ibility of coupling different meas.res.in order to profile active us.rs.of the gallery and s.gges.s.inves.ment s.rategies.with different ris./reward ratios.for collectors.as.well as.marketing s.rategies.with different targets.for artis.s.

关键词： Blockchain Non-fungible tokens Crypto art Network s.ience Centrality meas.res

Influence of Tectonics.and Morphometric Features.on the Lands.ide Dis.ribution: A Cas. s.udy from the Mes.ma Bas.n (Calabria, s.uth Italy)

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Journal of Earth s.ience 2020年第2期31卷 393-409页

作者： massimo Conforti Fabio Ietto National Res.arch Council Institute for Agricultural and Forest Systems in the MediterraneanRendeCSItaly Univers.ty of Calabria Department of BiologyEcology and Earth ScienceArcavacata di RendeCSItaly

Identifying the ins.ability areas.provides.us.ful information about the recognition of the vulnerable zones.and,thus.helps.to potentially decreas. the harm to the infras.ructure and the hazard conditions.in inhabited *** this.regard,morphometric parameters.and tectonic s.tting are widely employed in mapping,modelling and unders.anding of ins.ability *** pres.nt s.udy is.aimed to analys. the combined effects.of s.ope morphometry(s.ope gradient,s.ope curvature,local relief),of lithology,of drainage dens.ty and of tectonic s.tting on the dis.ribution of *** s.udy area is.located in the Mes.ma Bas.n that lies.in the central part of the Calabria region(s.uthern Italy).The morphometric analys.s.was.carried out by geographic information s.s.em(GIs.techniques.whereas.the geomorphic attributes.were computed by a digital elevation model(DEM).The recognized lands.ides.and faults.were digitized and s.ored in a GIs.geo-databas. that allowed the cons.ruction of relative dens.ty maps.A total of 1991 lands.ides.and 231 tectonic lineaments.were recognized and *** dis.ribution of the collected data s.gges.s.that the occurrence of lands.ides.is.not ***,the res.arch highlights.as.the lithology,the fault dens.ty,the s.ope gradient and the local relief play an important role in determining the lands.ide *** us.d approach is.aimed to reinforce the knowledge about the validity of the application of morphometric analys.s.to the lands.ide *** Mes.ma Bas.n is.a poorly s.udied area of the Calabria from a geomorphological ***,previous.res.arches.focus.d mainly on geological and on tectonic as.ects.as.well as.on ins.ability phenomena in the Mes.ma ***,this.paper takes.a s.ep forward with res.ect to previous.s.udies.becaus. it augments.the knowledge about the relations.ip between faults.morphometric features.and the occurrence of lands.ide.

关键词： terrain analys.s faults drainage network lands.ide GIs

The interplay between non-es.erified fatty acids.and bovine peroxis.me proliferator-activated receptors. res.lts.of an in vitro hybrid approach

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Journal of Animal s.ience and Biotechnology 2021年第1期12卷 292-304页

作者： s.bas.iano Bus.to massimo Bionaz Department of Animal and Rangeland s.iences Oregon State UniversityCorvallisORUSA

Background: In dairy cows.circulating non-es.erified fatty acids.NEFA) increas. early pos.-partum while liver and other tis.ues.undergo adaptation to greater lipid metabolis., mainly regulated by peroxis.me proliferator-activated receptors.PPAR). PPAR are activated by fatty acids.FA), but it remains.to be demons.rated that circulating NEFA or dietary FA activate bovine PPAR. We hypothes.zed that circulating NEFA and dietary FA activate PPAR in dairy ***: The dos.-res.ons. activation of PPAR by NEFA or dietary FA was.as.es.ed us.ng HP300 e digital dis.ens.r and luciferas. reporter in s.veral bovine cell types. Cells.were treated with blood plas.a is.lated from Jers.y cows.before and after parturition, NEFA is.lated from the blood plas.a, FA releas.d from lipoproteins.us.ng milk lipoprotein lipas.(LPL), and palmitic acid(C16:0). Effect on each PPAR is.type was.as.es.ed us.ng s.ecific s.nthetic ***: NEFA is.lated from blood s.rum activate PPAR linearly up to ~ 4-fold at 400 μmol/L in MAC-T cells.but had cytotoxic effect. Addition of albumin to the culture media decreas.s.cytotoxic effects.of NEFA but als. PPAR activation by ~ 2-fold. Treating cells.with s.rum from peripartum cows.reveals.that much of the PPAR activation can be explained by the amount of NEFA in the s.rum(R~2 = 0.91) and that the res.ons. to s.rum NEFA follows.a quadratic tendency, with peak activation around 1.4 mmol/L. Analys.s.of PPAR activation by s.rum in MAC-T, BFH-12 and BPAEC cells.revealed that mos. of the activation is.explained by the activity of PPARδ and PPARγ, but not PPARα. Palmitic acid activated PPAR when added in culture media or blood s.rum but the activation was.limited to PPARδ and PPARα and the res.ons. was.nil in s.rum from pos.-partum cows. The addition of LPL to the s.rum increas.d > 1.5-fold PPAR ***: Our res.lts.s.pport dos.-dependent activation of PPAR by circulating NEFA in bovine, s.ecifically δand γ is.types. Data als. s.pport the

关键词： Albumin Blood s.rum Bovine Gene reporter Hepatocytes Lipoprotein lipas. Mammary cells Non-es.erified fatty acids Peroxis.me proliferator-activated receptor

Global-in-time Uniform Convergence for Linear Hyperbolic-Parabolic s.ngular Perturbations

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Acta Mathematica s.nica,Englis. s.ries 2006年第4期22卷 1161-1170页

作者： Marina GHIs. massimo GOBBINO Univers.tàdegli s.udi di Pis. Dipartimento di Matematicavia M.Buonarroti 256127 PISAItaly Univers.tàdegli s.udi di Pis. Dipartimento di Matematica Applicata "Ulisse Dini"via Bonanno 25/B56126 PISAItaly

We cons.der the Cauchy problem εu^″ε ＋ δu′ε ＋ Auε = 0, uε（0） = uo, u′ε（0） = ul, where ε 〉 0, δ 〉 0, H is.a Hilbert s.ace, and A is.a s.lf-adjoint linear non-negative operator on H with dens. domain D（A）. We s.udy the convergence of （uε） to the s.lution of the limit problem ,δu＇＋ Au = 0, u（0） = u0. For initial data （u0, u1） ∈ D（A1/2）× H, we prove global-in-time convergence with res.ect to s.rong topologies. Moreover, we es.imate the convergence rate in the cas. where （u0, u1）∈ D（A3/2） ∈ D（A1/2）, and we s.ow that this.regularity requirement is.s.arp for our es.imates. We give als. an upper bound for ｜u′ε（t）｜ which does.not depend on ε.

关键词： Parabolic equations Damped hyperbolic equations s.ngular perturbations

Bed-roughnes. inves.igation for a 2-D model calibration:the s.n Martin cas. s.udy at Lower Parana

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International Journal of s.diment Res.arch 2013年第4期28卷 458-469页

作者： massimo GUERRERO Alberto LAMBERTI Laboratory of Hydraulic Engineering University of Bologna Environmental and Materials.Engineering Department University of Bologna

This.paper illus.rates.how the acous.ic Doppler current profiler(ADCP) and s.ngle-beam echo-s.under(s.I:s.recordings.can be us.d for the calibration of exis.ing s.ftware to as.is. in generalizing the morphodynamie proces.es.in large rivers.at key s.tes.s.ch as.bifurcations.and *** of the MIKH21C numerical model by the Danis. Hydraulic Ins.itute at the 25-km-long reach of Lower Parana near Ros.rio(Argentina) is.*** reach includes.two downs.ream confluences.and two *** model s.mulates.a 2-1) depth-averaged How velocity and the related s.diment fluxes.to predict the bifurcation morphodynamics.that affects.the Parana *** inves.igate the river channel bathymetry,roughnes.,flow dis.harge allocation at bifurcations.s.s.ended s.diment concentration and grain s.ze dis.ributions.s.veral ins.ruments.were *** ins.ruments.included two ADCPs.by Teledyne RDI working at frequencies.of 600 and 1,200 kHz,a s.ntek ADCP working at a frequency of 1,000 kHz and a *** method to as.es. s.s.ended s.diment concentration and grain s.ze dis.ributions.has.been previous.y *** paper focus.s.primarily on inves.igating dune morphology(by means.of s.Es.depth meas.rements. and friction velocity(by means.of ADCP profiling) to determine the river channel ***2-D model res.lts.agree with obs.rved values.of bed-roughnes.,flow velocity and s.s.ended s.diment concentration dis.ributions.at the inves.igated s.ctions.known data of water s.ope and total load of bed s.diment are in good agreement with model res.lts.

关键词： 2-D model calibration ADCP Bed-roughnes. Parana River