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Testing carbonate chemostratigraphy across differentiated ancient shallow-platform environments(Early Kimmeridgian,s Iberia)

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geoscience Frontiers 2019年第6期10卷 2203-2218页

作者： Rute Coimbra Beatriz marques Federico Oloriz geoBioTec Departamento de GeocienciasUniversidade de AveiroPortugal MARE Departamento de Ciencias da TerraUniversidade de CoimbraPortugal Faculdade de Ciencias e Tecnologia Universidade Nova de LisboaPortugal Departamento de Estratigrafia y Palaeontologia Universidad de GranadaSpain

shallow-platform settings with marked differences in paleoplatform bottom physiography influence the degree of connection with oceanic waters and overall circulation patterns,even when sharing the same palaeoclimatic *** Kimmeridgian shallow-marine settings have been explored to test the sensitivity and reliability of carbonate chemostratigraphy to detect such *** integrated overview of the obtained elemental trends depicted four major facies,shared along specific stratigraphic intervals of both depositional *** obliterated original geochemical signals only throughout the siliciclastics-rich interval,corresponding to the most landward *** the remaining facies,elemental features could be attributed to the differential action of forcing mechanisms operating along the south-Iberian paleomargin during Kimmeridgian *** highest degree of continental influence can be recognized by a strong relationship between Fe and Mn for the most proximal setting,which fades out along the mixed carbonate-fine siliciclastic rhythmic deposition in more open settings.A characteristic geochemical signature of progressively more positiveδ^(13)C values and significantly higher sr content is identified for the interval dominated by biogenic sponge *** a local response is related to local forcing by upwelling in the surroundings of a coral *** geochemical signature of a hydrothermal origin can be clearly differentiated from the influence of mere terrigenous ***,the decoupling of Fe and Mn along marginal settings is the clue to detecting major events of palaeogeographic *** temporal variations in Mg content along both studied sections are attributed to tectonic activity influencing nearshore/coastal water *** integrating chemostratigraphic information and complementary evidence,the palaeoenvironmental mechanisms promoting differentiated sedimentary records along ancient subtropical,shallow

关键词： Palaeoenvironment Carbonate chemostratigraphy shallow-water carbonates Diagenesis Kimmeridgian

Predicting stable crystalline compounds using chemical similarity

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npj Computational Materials 2021年第1期7卷 99-107页

作者： Hai-Chen Wang silvana Botti Miguel A.L.marques Institut für Physik Martin-Luther-Universität Halle-Wittenberg06120 Halle(Saale)Germany Institut für Festkörpertheorie und-Optik Friedrich-Schiller-Universität Jena and European Theoretical Spectroscopy FacilityMax-Wien-Platz 107743 JenaGermany

We propose an efficient high-throughput scheme for the discovery of stable crystalline *** approach is based on the transmutation of known compounds,through the substitution of atoms in the crystal structure with chemically similar *** concept of similarity is defined quantitatively using a measure of chemical replaceability,extracted by data-mining experimental *** this way we build 189,981 possible crystal phases,including 18,479 that are on the convex hull of *** resulting success rate of 9.72%is at least one order of magnitude better than the usual success rate of systematic high-throughput calculations for a specific family of materials,and comparable with speed-up factors of machine learning filtering *** a characterization of the set of 18,479 stable compounds,we calculate their electronic band gaps,magnetic moments,and *** approach,that can be used as a filter on top of any high-throughput scheme,enables us to efficiently extract stable compounds from tremendously large initial sets,without any initial assumption on their crystal structures or chemical compositions.

关键词： stability similarity crystalline

Large ferro-pyro-phototronic effect in 0.5Ba(Zr_(0.2)Ti_(0.8))O_(3)-0.5(Ba_(0.7)Ca_(0.3))TiO_(3)thin films integrated on silicon for photodetection

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Carbon Energy 2023年第6期5卷 1-10页

作者： JoséP.B.silva Katarzyna gwozdz Luís s.marques Mario Pereira Maria J.M.gomes Judith L.MacManus‐Driscoll Robert L.Z.Hoye Centre of Physics of Universities of Minho and Porto(CF‐UM‐UP) University of MinhoBragaPortugal Laboratory of Physics for Materials and Emergent Technologies LapMETUniversity of MinhoBragaPortugal Department of Quantum Technologies Faculty of Fundamental Problems of TechnologyWroclaw University of Science and TechnologyWroclawPoland Department of Materials science and Metallurgy CambridgeUK Inorganic Chemistry Laboratory Department of ChemistryUniversity of OxfordOxfordUK Department of Materials Imperial College LondonLondonUK

Coupling together the ferroelectric,pyroelectric,and photovoltaic characteristics within a single material is a novel way to improve the performance of *** this work,we take advantage of the triple multifunctionality shown by 0.5Ba(Zr_(0.2)Ti_(0.8))O_(3)-0.5(Ba_(0.7)Ca_(0.3))TiO_(3)(BCZT),as demonstrated in an Al/si/siOx/BCZT/ITO thin-film *** si/siOx acts as an n-type layer to form a metal-ferroelectric-insulator-semiconductor heterostructure with the BCZT,and with Al and ITO as *** photo-response of the device,with excitation from a violet laser(405 nm wavelength),is carefully investigated,and it is shown that the photodetector performance is invariant with the chopper frequency owing to the pyro-phototronic effect,which corresponds to the coupling together of the pyroelectric and photovoltaic ***,the photodetector performance was significantly better than that of the devices operating based only on the pyro-phototronic effect by a factor of 4,due to the presence of ferroelectricity in the ***,after a poling voltage of−15 V,for a laser power density of 230mW/cm^(2)and at a chopper frequency of 400Hz,optimized responsivity,detectivity,and sensitivity values of 13.1mA/W,1.7×10^(10)Jones,and 26.9,respectively,are ***,ultrafast rise and fall times of 2.4 and 1.5μs,respectively,are obtained,which are 35,000 and 36,000 times faster rise and fall responses,respectively,than previous reports of devices with the ferro-pyro-phototronic *** is understood based on the much faster ferroelectric switching in ferroelectric thin films owing to the predominant 180°domains in a single direction out of plane.

关键词： ferroelectric ferro-pyro-phototronic effect photodetector polarization-controlled response

Foliar application of rare earth elements on soybean(glycine max(L)):Effects on biometrics and characterization of phytotoxicity

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Journal of Rare Earths 2020年第10期38卷 1131-1139,I0005页

作者： Eduardo s.Rodrigues gabriel s.Montanha Joao P.R.marques Eduardo de Almeida Lauren N.M.Yabuki Amauri A.Menegario Hudson W.Pereira de Carvalho Laboratory of Nuclear Instrumentation(LIN) Center for Nuclear Energy in Agriculture(CENA)University of Sao Paulo(USP)PiracicabaSP13416-000Brazil Environmental studies Center Sao Paulo State University(UNESP)Rio ClaroSP13506-900Brazil

This study aims at investigating the effects of foliar application of aqueous solutions of La3+and Ce3+nitrates on soybean plants(glycine max).First,we observe that Triton HW 1000 surfactant at 0.01 vol%reduces droplets contact angle and increases their drying *** greenhouse conditions,the foliar treatments do not affect chlorophyll content,plant height,number of leaves,number of pods,number of seeds per pod,and average seed ***,the treatments induce phytotoxicity since foliar injuries appear after the *** X-ray fluorescence spectroscopy combined to scanning electron microscopy shows that the leaf lesions are positively correlated to accumulation of Ce and La on the leaf surface and also promote structural alteration to the epidermal cells.X-ray absorption near edge structure shows that the La and Ce nitrates are partially bio transformed into oxides by the leaves which might explain the harmful effects.

关键词： Leaf fertilization Rare earth elements soybean X-ray fluorescence spectroscopy X-ray absorption spectroscopy

Effectiveness of rotavirus vaccines against rotavirus infection and hospitalization in Latin America: systematic review and metaanalysis

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Infectious Diseases of Poverty 2016年第1期5卷 764-775页

作者： Victor s.santos Daniella P.marques Paulo R.s.Martins-Filho Luis E.Cuevas Ricardo Q.gurgel Postgraduate Program in Health sciences Federal University of SergipeRua Cláudio Batista s/nAracajuSergipe Zip code:49060-108Brazil Department of Medicine Federal University of SergipeAracajuSergipeBrazil Investigative Pathology Laboratory Federal University of SergipeAracajuSergipeBrazil Liverpool school of Tropical Medicine LiverpoolUK

Background:Rotavirus was the leading cause of childhood diarrhoea-related hospitalisations and death before the introduction of rotavirus ***:We describe the effectiveness of rotavirus vaccines to prevent rotavirus infections and hospitalizations and the main rotavirus strains circulating before and after vaccine introduction through a systematic review and meta-analysis of studies published between 1990 and 2014.203 studies were included to estimate the proportion of infections due to rotavirus and 10 to assess the impact of the vaccines.41 of 46 studies in the post-vaccination period were used for meta-analysis of genotypes,20 to calculate VE against infection,eight for VE against hospitalisation and seven for VE against severe ***:24.3%(95%CI 22.1–26.5)and 16.1%(95%CI 13.2–19.3)of cases of diarrhoea were due to rotavirus before and after vaccine introduction,*** most prevalent g types after vaccine introduction were g2(51.6%,95%CI 38–65),g9(14.5%,95%CI 7–23)and g1(14.2%,95%CI 7–23);while the most prevalent P types were P[4](54.1%,95%CI 41–67)and P[8](33%,95%CI 22–46).g2P[4]was the most frequent genotype combination after vaccine *** was 53%(95%CI 46–60)against infection,73%(95%CI,66–78)against hospitalisation and 74%(95%CI,68.0–78.0)against severe *** in hospitalisations and mortality due to diarrhoea were observed in countries that adopted universal rotavirus ***:Rotavirus vaccines are effective in preventing rotavirus-diarrhoea in children in Latin *** vaccines were associated with changes in genotype distribution.

关键词： Rotavirus vaccines Rotavirus vaccine effectiveness Rotavirus genotype Meta-analysis Latin America

Computational screening of materials with extreme gap deformation potentials

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npj Computational Materials 2022年第1期8卷 1482-1491页

作者： Pedro Borlido Jonathan schmidt Hai-Chen Wang silvana Botti Miguel A.L.marques Institut für Festkörpertheorie und-optik Friedrich-Schiller-Universität Jena and European Theoretical Spectroscopy FacilityMax-Wien-Platz 107743JenaGermany CFisUC Department of PhysicsUniversity of CoimbraRua Larga3004-516CoimbraPortugal Institut für Physik Martin-Luther-Universität Halle-WittenbergD-06099HalleGermany

In this work,we present a large-scale study of gap deformation potentials based on density-functional theory calculations for over 5000 *** expected,in most cases the band gap decreases for increasing volume with deformation potentials that can reach values of almost−15 *** find,however,also a sizeable number of materials with positive deformation *** members of this group are halide perovskites,known for their applications in *** then focus on understanding the physical reasons for so different values of the deformation potentials by investigating the correlations between this property and a large number of other material and compositional *** also train explainable machine learning models as well as graph convolutional networks to predict deformation potentials and establish simple rules to understand predicted ***,we analyze in more detail a series of materials that have record positive and negative deformation potentials.

关键词： deformation properties. extreme

The use of remote sensing to detect the consequences of erosion in gypsiferous soils

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International soil and Water Conservation Research 2020年第4期8卷 383-392页

作者： Maria Jose marques Ana Alvarez Pilar Carral Blanca sastre Ramón Bienes geology and geochemistry Department Autonomous University of MadridCalle Francisco Tomás y Valiente728040MadridSpain Department of Applied Research and Agrarian Extension IMIDRAFinca El Encín.Carretera A-2Km 38.8.Alcaláde Henares28800MadridSpain

Tillage practices on sloping ground often result in unsustainable soil losses impairing soil functions such as crop productivity,water and nutrients storage,and soil organic carbon(sOC)sequestration.A sloping olive grove(10%)was planted in shallow gypsiferous soils in *** was managed by minimum tillage;the most frequent management practice in central *** consequences of erosion were studied in soil samples(at 0-10,10-20,and 20-30 cm depths)by analyzing sOC,available water and gypsum content,and by detecting spectral signatures using an AsD FieldspecPro(R)VIs/*** Brightness index(BI),shape index(FI),and Normalized Difference Vegetation Index(NDVI)were derived from the AsD spectral signatures and from remote sensing(sentinel-2 image)*** development of these young olive trees was estimated from the measured diameter of the trunks(17±18 cm diameter).In 20-30 cm of the soil,the carbon stock(38±18 Mg ha-1)as well as the available water content(12±6%)was scarce,affecting the productivity of the olive *** above-mentioned indices obtained from the laboratory samples and the pixels of the sentinel-2 image were significantly(ps related to the gypsum content and the slope of the *** FI was related to the carbon and water *** NDVI derived from the satellite image identified the influence of soil degradation on the trees and the carbon *** spatialtemporal changes of the indices might help in tracking soil changes over time.

关键词： Tillage Erosion NDVI gypsum Remote sensing soil color

The Role of Institutions:A Cross-country Analysis of Renminbi Trading in Foreign Exchange Markets

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China & World Economy 2022年第3期30卷 42-74页

作者： Marina Zucker-marques Pedro Perfeito da silva Division on globalization and Development strategies United Nations Conference on Trade and Development(UNCTAD)Switzerland Political science Department Central European UniversityAustria

We explore how China's geographically targeted policies impact RMB overseas use individually or in *** policies include swap agreements,clearing banks,investment quotas,and direct trading between Chinese renminbi(RMB)and non-UsD *** a fuzzy-set qualitative comparative analysis and using Bank of International settlements cross-country data on foreign exchange markets,we find that institution building has lowered the barriers to international adoption of the ***,for countries economically close to China,high RMB trading is explained by either(i)having a clearing bank in the host market and direct quotations between the RMB and the local currency,or(ii)being a financial center and having access to the Chinese capital *** combination of policies is explained by the creation of(i)"trading posts"that provide RMB liquidity abroad,and(ii)channels that allow actors to " recycle" offshore RMB *** triangulate our results with interviews conducted with senior People’s Bank of China officials.

关键词： foreign exchange markets fuzzy-set qualitative comparative analysis institutional context international monetary system offshore RMB trading RMB internationalization

Fabrication of Tailored Bragg gratings by the Phase Mask Dithering/Moving Technique

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Photonic sensors 2013年第1期3卷 81-96页

作者： Miguel MELO Paulo V. s. marques Department of Physics and Astronomy Faculty of Sciences University of Porto Rua do Campo Alegre 687 4169-007Porto Portugal INEsC TEC Rua do Campo Alegre 687 4169-007 Porto Portugal

The most relevant aspects related to the phase mask dithering/moving method for the fabrication of complex Bragg grating designs are reviewed. Details for experimental implementation of this technique is presented, including theoretical analysis of the calibration functions for the correct dither/displacement. Results from tailored Bragg grating structures fabricated by this method are shown. Apodized Bragg gratings with modeled spatial profiles were implemented, resulting in side mode suppression levels of more than 20 dB in gratings showing transmission filtering level higher than 30 dB. Chirped gratings with the spectral bandwidth up to 4 nm, π-shift and sampled Bragg gratings with equalized peaks equally spaced by 0.8 nm （100 gHz） were also fabricated.

关键词： Bragg gratings optical fiber filters optical fiber communications optical fiber sensors