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Journal of Minerals and Materials Characterization and Engineering 2014年第2期2卷 135-143页

作者： Maria-Ondina Figueiredo Teresa Pereira da Silva joao pedro veiga Daniel de Oliveira Maria joao Batista CENIMAT/I3N Faculty of Sciences and TechnologyNew University of LisbonCampus da CaparicaLisbonPortugal Unit of Mineral Resources and Geophysics National Laboratory for Energy and GeologyAmadoraPortugal

Rhenium is a very scarce element, occurring in the Earth's crust mainly carried by molybdenite (MoS2). Due to a very low availability comparative to actual industrial demand, rhenium is nowadays one of the most expensive mineral commodities and an increased interest is focused on ex- ploring residues resulting from a long-term mining, particularly of sulphide ore deposits. It is therefore noteworthy to assign the presence of rhenium (in a concentration up to 3 ppm) in the waste materials from the old sulphur factory at the abandoned mine of Sao Domingos (Iberian Pyrite Belt, Southeast Portugal), exploited since the Roman occupation of Iberia. Aiming at a potential sustainable recovery of rhenium as a by-product, X-ray near-edge absorption spectroscopy (XANES) was applied to clarify the Re-binding and mode of occurrence by comparing Re L3-edge XANES spectra obtained from mine waste samples (previously fully characterized by X-ray laboratory techniques) with similar spectra collected from Re-rich molybdenites (Mo1-xRexS2) and from Re-O model compounds configuring various valences and coordination environments of rhenium ions. Obtained results are commented, ruling out a possible Re-S binding and rather conforming with the binding of rhenium to oxygen in the analysed mine waste materials.

关键词： Mine Waste Materials By-Products Iberian Pyrite Belt Rhenium XANES Re L_(3)-Edge

Influence of bed elevation discordance on flow patterns and head losses in an open-channel confluence

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Water Science and Engineering 2019年第3期12卷 235-243页

作者： pedro Xavier Ramos Laurent Schindfessel joao pedro Pego Tom De Mulder Department of Civil Engineering Ghent University Ghent 9000 Belgium Faculty of Engineering University of Porto Porto 4200-465 Portugal

Confluences play a major role in the dynamics of networks of natural and man-made open channels, and field measurements on river confluences reveal that discordance in bed elevation is *** of schematized confluences with a step at the interface between the tributary and the main channel bed reveal that bed elevation discordance is an important additional control for the confluence *** study aimed to improve understanding of the influence of bed elevation discordance on the flow patterns and head losses in a right-angled confluence of an open channel with rectangular cross-sections.A large eddy simulation (LES)-based numerical model was set up and validated with experiments by *** configurations with different bed discordance ratios were *** results confirm that, with increasing bed elevation discordance, the tributary streamlines at the confluence interface deviate less from the geometrical confluence angle, the extent of the recirculation zone (RZ) gets smaller, the ratio of the water depth upstream to that downstream of the confluence decreases, and the water level depression *** bed elevation discordance also leads to the development of a large-scale structure in the lee of the *** the appearance of the large-scale structure, the reduced extent of the RZ and associated changes in flow deflection/contraction reduce total head losses experienced by the main channel with an increase of the bed discordance *** turns out that bed elevation discordance converts the lateral momentum from the tributary to streamwise momentum in the main channel more efficiently.

关键词： Open channel confluence Bed elevation discordance Three-dimensional numerical modelling Large eddy simulation Recirculation zone

Development the Steel Industry Waste-free by Internal Recycling of the Blast Furnace Dusts

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材料科学与工程（中英文B版） 2011年第5期1卷 630-635页

作者： Ciocan Anisoara Potecasu Florentina veiga joao pedro Department of Environment Engineering and Technological Systems University of ＂Dunarea de Jos＂ Galati Romania Department of Materials Science and Engineering University of ＂Dunarea de Jos ＂ Galati Romania CENIMAT/Materials Science Department Nova University Lisbon Caparica Portugal

The development of steel industry is subject to solve major problems strictly targeted on pollution control and protection of natural resources and energy. The development strategies of steel integrated works around the world have two directions: development of the advanced technologies in respect to the substantially decreasing emissions and increasing the recycling ratio of the wastes and by-products. In this paper, a solution is analyzed for integrated management of blast furnace dusts in accordance with their essential quantification (quantitative, qualitative and the generation sources) and transformation of these wastes into valuable by-products used directly by the company in an internal process. The physical and chemical properties that are relevant for recycling solution are discussed as respect to the optimum valorization. Also, the morphology and mineralogy of these dusts are presented in accordance with fundamental aspects of its generation process.

关键词：粉尘回收废物转化高炉粉尘钢铁工业钢铁行业自然资源控制污染定量分析

Molecular characterization of an extensively drug-resistant Acinetobacter baumannii isolated from a corn culture soil

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Pedosphere 2021年第6期31卷 973-976页

作者： joao pedro Rueda FURLAN Eliana Guedes STEHLING Departamento de Analises Clinicas Toxicologicas e BromatologicasFaculdade de CienciasFarmaceuticas de Ribeirao PretoUniversidade de Sao Paulo(USP)Ribeirao Preto SP 14040-903(Brazil)

Dear Editor,Soil is the most biodiverse habitat on Earth and it has been estimated that one gram of soil can contain up to one billion bacterial cells(Fierer,2017).The microorganisms of soil produce a wide variety of ... 详细信息

关键词： soil corn culture

Structural Optimization of Metal and Polymer Ore Conveyor Belt Rollers

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 601-618页

作者： joao pedro Ceniz Rodrigo de Sá Martins Marco Antonio Luersen Tiago Cousseau Department of Mechanical Engineering Federal University of Technology-Parana(UTFPR)Curitiba81280-340Brazil

Ore conveyor belt rollers operate in harsh environments,making them prone to premature *** service lives are highly dependent on the stress field and bearing misalignment angle,for which limit values are defined in a *** this work,an optimization methodology using metamodels based on radial basis functions is implemented to reduce themass of twomodels of *** a structural point of view,one of the rollers ismade completely of metal,while the other also has some components made of polymeric *** objective of this study is to develop and apply a parametric structural optimization methodology to minimize the mass of the two models of *** represent the mechanical behavior of the rollers,simulations were performed using the finite element *** the numerical optimization process,the variable parameters were the dimensions of the shaft and external *** geometric configuration that corresponded at the same time to the lowest mass and acceptable ranges for the stress and bearingmisalignment angle was *** the proposed methodology,a 32.3% reduction in mass was obtained for a metal roller design and an 18.9% reduction for a polymer *** both cases,the constraints were not *** the all-metal roller,the safety factors for the maximum stress and bearingmisalignment angle were 1.44 and 1.75,respectively,while for the polymer roller the corresponding figures were 1.50 and *** work describes a low-computational-cost optimization methodology for roller designs that have been little studied in the ***,the methodology could be adapted for use with other types of rollers and rollers made of different materials.

关键词： Conveyor belt rollers structural optimization surrogate models radial basis functions

Abiotic stress on seed germination and plant growth of Zeyheria tuberculosa

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林业研究:英文版 2023年第5期34卷 1511-1522页

作者： Robson Luis Silva de Medeiros Rinaldo Cesar de Paula joao Vitor Oliveira de Souza joao pedro Peixoto Fernandes Department of Agricultural Sciences School of Agricultural and Veterinarian SciencesSao Paulo State University(Unesp)14884-900JaboticabalSao PauloBrazil

Zeyheria tuberculosa(Vell.)Bureau ex *** among the Brazilian flora threatened with *** has high-quality wood and can be used to recover herbicidecontaminated ***,abiotic stresses can harm seed germination and seedling development under adverse conditions and need to be understood to improve autochthonous or indigenous biodiversity conservation and strengthen reforestation *** study evaluated the effects of temperature,water and saline stress on *** seed germination and water stress on seedling *** laboratory experiments evaluated germination under:(1)different temperatures(20,25,30,35 and 40℃);(2)different water potentials simulated with polyethylene glycol(PEG6000)at 25 and 30℃;and,(3)different osmotic potentials simulated with NaCl at 25 and 30℃.In addition,a greenhouse experiment subjected seedlings to five water regimes(20%,35%,50%,65%and 80%of maximum substrate water holding capacity).In the laboratory,seedling biometry and germination were evaluated,while physiological and morphological parameters were assessed in the *** potential of seeds increased at 25 and 30℃.Germination and vigor decreased as water and saline stresses *** tolerance thresholds for water and salt stresses were-0.6 and-0.4 MPa,*** the greenhouse,the most restrictive water regimes reduced seedling physiological and morphological *** development was compromised at moisture levels below50%field capacity.

关键词： Bignoniaceae Climate change Ipê-felpudo Ipê-preto Water stress

Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

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Frontiers of Structural and Civil Engineering 2015年第1期9卷 1-16页

作者： joao pedro SANTOS Christian CREMONA Andre D. ORCESI Paulo SILVEIRA Luis CALADO Department of Structures Av. Brasil 101 Lisbon 1700-066 Portugal Technical Center for Bridge Engineering CEREMA B.P. 214 Provins Cedex 77487 France Materials and Structures Department IFSTTAR University Paris-Est 14-20 Boulevard Newton Champs sur Marne Marne la Vallee Cedex2 F-77447 France Department of Civil Engineering Technical University Lisbon Avenida Rovisco Pais Lisbon 1096 Portugal

A large amount of researches and studies have been recently performed by applying statistical and machine learning techniques for vibration-based damage detection. However, the global character inherent to the limited number of modal properties issued from operational modal analysis may be not appropriate for early-damage, which has generally a local character. The present paper aims at detecting this type of damage by using static SHM data and by assuming that early-damage produces dead load redistribution. To achieve this objective a data driven strategy is proposed, consisting of the combination of advanced statistical and machine learning methods such as principal component analysis, symbolic data analysis and cluster analysis. From this analysis it was observed that, under the noise levels measured on site, the proposed strategy is able to automatically detect stiffness reduction in stay cables reaching at least 1%.

关键词： structural health monitoring early-damage detection principal component analysis symbolic data symbolic dissimilarity measures cluster analysis numerical model damage simulations

High-precision geochronology of Mesozoic magmatism in Macao,Southeast China:Evidence for multistage granite emplacement

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Geoscience Frontiers 2020年第1期11卷 243-263页

作者： pedro Quelhas Agata Alveirinho Dias joao Mata Donald Wayne Davis Maria Luísa Ribeiro Institute of Science and Environment University of Saint JosephMacaoChina Instituto Dom Luiz Faculdade de CiênciasUniversidade de LisboaLisboaPortugal Jack Satterly Geochronology Laboratory Department of Earth SciencesUniversity of TorontoTorontoOntCanada Laboratório Nacional de Engenharia e Geologia LisboaPortugal

Six new high precision U-Pb zircon ID-TIMS ages plus thirteen in situ high spatial resolution U-Pb zircon LA-MC-ICPMS ages are reported from Jurassic plutonic(metaluminous to weakly peraluminous biotite granites)and Jurassic to Cretaceous hypabyssal(dacites)rocks from *** its relatively small area(~30 km^2),the new ages tightly constrain the Macao granitic magmatism to two periods ranging from 164.5±0.6 Ma to 162.9±0.7 Ma and 156.6±0.2 Ma to 155.5±0.8 Ma,separated by ca.6 *** zircons point to the existence of a basement with ages up to Paleo-Proterozoic and late Archean in the *** addition,younger dacitic rocks were dated at 150.6±0.6 Ma and<120 Ma.U-Pb zircon ages and whole-rock REE data of Macao granites indicate that the first pulse is also represented in Hong Kong and Southeast(SE)China,while magmatism with the chemical characteristics of the second pulse seems to not be represented outside *** two granitic magmatic pulses have distinct mineralogical and geochemical features that support their discrete nature rather than a continuum of comagmatic activity and suggest that the Macao granitic suite was incrementally assembled during a period of ca.9 Ma,a hypothesis also extendable to the neighboring Hong Kong region for a time lapse of ca.24 *** Macao,the transition from granitic magmatism(Middle to Upper Jurassic)to the younger dacite dykes(Upper Jurassic to Lower Cretaceous)most likely corresponds to a change in the regional tectonic setting,from an extensional regime related with foundering of the subducting paleoPacific plate during the Early Yanshanian period to the reestablishment of a normal subduction system in SE China during the Late Yanshanian period.

关键词： Granites U-Pb geochronology Zircon Jurassic Yanshanian orogeny Macao

Conformal and continuous deposition of bifunctional cobalt phosphide layers on p-silicon nanowire arrays for improved solar hydrogen evolution

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Nano Research 2018年第9期11卷 4823-4835页

作者： Sitaramanjaneva Mouli Thalluri Jerome Borme Kang Yu Junyuan Xu Isilda Amorim joao Gaspar Liang Qiao Paulo Ferreira pedro Alpuim Lifeng Liu International Iberian Nanotechnology Laboratory (INL) Av. Mestre. Jose Veiga Braga 4715-330 Portugal Materials Science and Engineering Program University of Texas at Austin Austin TX78712 USA Deportment of Chemistry State Key Laboratory of Molecular Engineering of Polymers and Institute of Biomedical Sciences Fudon University Shanghai 200433 China Mechanical Engineering Department and IDMEC Instituto Superior Tdcnico University of Lisbon Av. Rovisco Pais Lisboa 1049-007 Portugal Center of Physics University of Minho Braga 4710-057 Portugal

Vertically aligned p-silicon nanowire （SiNW） arrays have been extensively investigated in recent years as promising photocathodes for solar-driven hydrogen evolution. However, the fabrication of SiNW photocathodes with both high photoelectrocatalytic activity and long-term operational stability using a simple and affordable approach is a challenging task. Herein, we report conformal and continuous deposition of a di-cobalt phosphide （C02P） layer on lithography- patterned highly ordered SiNW arrays via a cost-effective drop-casting method followed by a low-temperature phosphorization treatment. The as-deposited C02P layer consists of crystalline nanoparticles and has an intimate contact with SiNWs, forming a well-defined SiNW@Co2P core/shell nanostructure. The conformal and continuous Co2P layer functions as a highly efficient catalyst capable of substantially improving the photoelectrocatalytic activity for the hydrogen evolution reaction （HER） and effectively passivates the SiNWs to protect them from photo-oxidation, thus prolonging the lifetime of the electrode. As a consequence, the SiNW@Co2P photocathode with an optimized C02P layer thickness exhibits a high photocurrent density of -21.9 mA·cm^-2 at 0 V versus reversible hydrogen electrode and excellent operational stability up to 20 h for solar-driven hydrogen evolution, outperforming many nanostructured silicon photocathodes reported in the literature. The combination of passivation and catalytic functions in a single continuous layer represents a promising strategy for designing high-performance semiconductor photoelectrodes for use in solar-driven water splitting, which may simplify fabrication procedures and potentially reduce production costs.

关键词： solar-driven hydrogenevolution silicon nanowire cobalt phosphide photoelectrochemical water splitting drop-casting

Combined penetrating keratoplasty, pars plana vitrectomy and Ahmed glaucoma valve implant after open globe injury： a challenging approach

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International Journal of Ophthalmology(English edition) 2017年第11期10卷 1786-1788页

作者： joao Beato Antonio B.Melo pedro A.Faria Luis Torrao Fernando Falcao-Reis Department of Ophthalmology Sao Joao Hospital CenterPorto 4200-319 Portugal Department of Sense Organs Faculty of Medicine University of Porto Porto 4200-319 Portugal

Dear Editor,I am ***？o Beato,from the Ophthalmology Department of Sao Jo？o Hospital Center,Porto,Portugal.I write to present a case of combined penetrating keratoplasty（PKP）with temporary Eckardt keratoprosthesis,

关键词： OCULAR TRAUMA OUTCOMES