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Spatial distribution of morphometric parameters of glacial cirques in the Central Pyrenees(Aran and Boí valleys)

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Journal of Mountain Science 2018年第10期15卷 2103-2119页

作者： Luis LOPES Marc OLIVA Marcelo FERNANDES Paulo PEREIRA Pedro PALMA Jesús RUIZ-FERNáNDEZ Centre for Geographical Studies – IGOT Universidade de Lisboa Department of Geography University of Barcelona Environmental Management center Mykolas Romeris University Department of Geography University of Oviedo

Glacial cirques are typical landscape features of mid-latitude mountain environments like the Central Pyrenees. Their morphology as well as their spatial distribution provides insights about past glaciers and climates. In this study, we examine the distribution, morphometrical and topographical characteristics of glacial cirques in two U-shaped glacial valleys located in the Central Pyrenees – the Aran and the Boí valleys. They are located in different aspects of this mountain range(north vs south) under different climatic influences that promoted distinct glaciation patterns during the late Pleistocene. The spatial mapping of these landforms was carried out using high-resolution imagery and field observations. We analysed the data of the morphometrical and topographical variables of the glacial cirques by using different statistical and geospatial methods in order tounveil the factors controlling their formation and development. A total of 186 glacial cirques were mapped in the study area, including 119 in the Aran and 67 in the Boí valleys. The local topography and microclimate conditions lead to substantial differences in both areas in terms of the morphology and dimensions of the cirques. Glacial cirques in Boí are distributed at slightly higher elevations than in Aran and they are also larger, though their dimensions decrease with elevation in both valleys. Aran cirques are mostly oriented NE, while Boí landforms do not show any prevailing aspect. Even though lithology does not control the distribution of the glacial cirques, some specific lithological settings may favour the development of larger cirques. In general, glacial cirques in the Aran and the Boí valleys show morphometrical properties similar to those reported in other mid-latitude mountain ranges.

关键词： Central Pyrenees Aran and Boi valleys glacial cirques topography morphometry.

Application of Bioinspired Superhydrophobic Surfaces in Two-phase Heat Transfer Experiments

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Journal of Bionic Engineering 2017年第3期14卷 506-519页

作者： Emanuele Teodori Ana Sofia Moita Miguel Moura Pedro Pontes Antonio Moreira Yuan Bai Xinlin Li Yan Liu IN+- center for Innovation Technology and Policy Research Instituto Superior T~enico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portuga Key Laboratory of Bionic Engineering (Ministry of Education) Jilin University Changchun 130022 China

This paper addresses the potential to use Lotus leafbioinspired surfaces in applications involving heat transfer with phase change, namely pool boiling and spray impingement. Besides describing the role of bioinspired topographical features, using an innovative technique combining high-speed visualization and time-resolved infrared thermography, surface durability is also addressed. Water is used for pool boiling and for spray impingement systems （simplified as single droplet impact）, while HFE7000 is used in a pool boiling cooler for electronic components. Results show that surface durability is quickly compro- mised for water pool boiling applications, as the chemical treatment does not withstand high temperatures （T 〉 100 ℃） during long time intervals （3 h - 4 h）. For HFE7000 pool boiling （depicting lower saturation temperature - 34 ℃）, heat transfer en- hancement is governed by the topography. The regular hierarchical pattern of the bioinspired surfaces promotes the heat transfer coefficient to increase up to 22.2%, when compared to smooth surfaces, while allowing good control of the interaction mechanisms until a distance between micro-structures of 300 gm- 400 Ixm. Droplet impingement was studied for surface temperatures ranging between 60 ℃ - 100 ℃. The results do not support the use of superhydrophobic surfaces for cooling applications, but reveal great potential for other applications involving droplet impact on heated surfaces （e.g. metallurgy in- dustry）.

关键词： bioinspired surfaces surface micro-patterning two-phase heat transfer time resolved infrared thermography

Kinetic approach to the study of froth flotation applied to a lepidolite ore

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 731-742页

作者： Nathália Vieceli Fernando O.Durao Carlos Guimaraes Carlos A.Nogueira Manuel F.C.Pereira Fernanda Margarido center for Innovation Technology and Policy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal CERENA-Centro de Recursos Naturais e Ambiente DECivilInstituto Superior TecnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laboratorio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal

The number of published studies related to the optimization of lithium extraction from low-grade ores has increased as the demand for lithium has grown. However, no study related to the kinetics of the concentration stage of lithium-containing minerals by froth flotation has yet been reported. To establish a factorial design of batch flotation experiments, we conducted a set of kinetic tests to determine the most selective alternative collector, define a range of pulp p H values, and estimate a near-optimum flotation time. Both collectors（Aeromine 3000 C and Armeen 12D） provided the required flotation selectivity, although this selectivity was lost in the case of pulp p H values outside the range between 2 and 4. Cumulative mineral recovery curves were used to adjust a classical kinetic model that was modified with a non-negative parameter representing a delay time. The computation of the near-optimum flotation time as the maximizer of a separation efficiency（SE） function must be performed with caution. We instead propose to define the near-optimum flotation time as the time interval required to achieve 95%–99% of the maximum value of the SE function.

关键词： lepidolite lithium ore treatment froth flotation kinetic analysis

Risk Governance,Assessment,and Economic Impacts

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International Journal of Disaster Risk Science 2017年第3期8卷 235-236页

作者： Paula Teves-Costa JoséManuel Mendes Instituto Dom Luiz Faculdade de Ciências Universidade de Lisboa European center on Urban Risks (CERU) center for Social Studies Faculty of Economics University of Coimbra

Due to climate change,growing urbanization,and population migration the social and economic impacts of natural hazards have been increasing *** challenge for risk science,both methodologically and conceptually,is to i... 详细信息

关键词： Risk Governance,Assessment,and Economic Impacts

Optimization of an innovative approach involving mechanical activation and acid digestion for the extraction of lithium from lepidolite

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 11-19页

作者： Nathalia Vieceli Carlos A.Nogueira Manuel F.C.Pereira Fernando O.Durao Carlos Guimaraes Fernanda Margarido center for Innovation Technology and Po icy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laborat6rio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal CERENA-Centro de Recursos Naturais e Ambiente DECivilInstituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal

The recovery of lithium from hard rock minerals has received increased attention given the high demand for this element. There- fore, this study optimized an innovative process, which does not require a high-temperature calcination step, for lithium extraction from le- pidolite. Mechanical activation and acid digestion were suggested as crucial process parameters, and experimental design and re- sponse-surface methodology were applied to model and optimize the proposed lithium extraction process. The promoting effect of amorphi- zation and the formation of lithium sulfate hydrate on lithium extraction yield were assessed. Several factor combinations led to extraction yields that exceeded 90%, indicating that the proposed process is an effective approach for lithium recovery.

关键词： lepidolite lithium mechanical activation acid digestion optimization extraction

A digital microfluidic system with 3D microstructures for single-cell culture

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Microsystems & Nanoengineering 2020年第1期6卷 1296-1305页

作者： Jiao Zhai Haoran Li Ada Hang-Heng Wong Cheng Dong Shuhong Yi Yanwei Jia Pui-In Mak Chu-Xia Deng Rui PMartins State-Key Laboratory of Analog and Mixed-Signal VLSI Institute of MicroelectronicsUniversity of MacaoMacao SARChina Faculty of Science and Technology-ECE University of MacaoMacao SARChina Cancer center Faculty of Health SciencesUniversity of MacaoMacao SARChina Liver Transplantation center the Third Affiliated HospitalSun Yat-sen University510000 GuangzhouChina on leave from Instituto Superior Técnico Universidade de LisboaLisboaPortugal

Despite the precise controllability of droplet samples in digital microfluidic(DMF)systems,their capability in isolating single cells for long-time culture is still limited:typically,only a few cells can be captured on an *** fabricating small-sized hydrophilic micropatches on an electrode aids single-cell capture,the actuation voltage for droplet transportation has to be significantly raised,resulting in a shorter lifetime for the DMF chip and a larger risk of damaging the *** this work,a DMF system with 3D microstructures engineered on-chip is proposed to form semi-closed micro-wells for efficient single-cell isolation and long-time *** optimum results showed that approximately 20%of the micro-wells over a 30×30 array were occupied by isolated single *** addition,low-evaporation-temperature oil and surfactant aided the system in achieving a low droplet actuation voltage of 36V,which was 4 times lower than the typical 150 V,minimizing the potential damage to the cells in the droplets and to the DMF *** exemplify the technological advances,drug sensitivity tests were run in our DMF system to investigate the cell response of breast cancer cells(MDA-MB-231)and breast normal cells(MCF-10A)to a widely used chemotherapeutic drug,Cisplatin(Cis).The results on-chip were consistent with those screened in conventional 96-well *** novel,simple and robust single-cell trapping method has great potential in biological research at the single cell level.

关键词： culture system sized

Combining spatial and economic criteria in tree-level harvest planning

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Forest Ecosystems 2020年第2期7卷 234-246页

作者： Petteri Packalen Timo Pukkala Adrián Pascual School of Forest Sciences University of Eastern FinlandPO Box 11180101 JoensuuFinland Forest Research center School of AgricultureUniversity of LisbonTapada da Ajuda1349-017 LisboaPortugal

Background:Modern remote sensing methods enable the prediction of tree-level forest resource ***,the benefits of using tree-level data in forest or harvest planning is not clear given a relative paucity of *** particular,there is a need for tree-level methods that simultaneously account for the spatial distribution of trees and other *** this study,we developed a spatial tree selection method that considers tree-level(relative value increment),neighborhood related(proximity of cut trees)and global objectives(total harvest).Methods:We partitioned the whole surface area of the stand to trees,with the assumption that a large tree occupies a larger area than a small *** was implemented using a power *** also utilized spatially explicit tree-level growth models that accounted for competition by neighboring *** was conducted with a variant of cellular *** proposed method was tested in stone pine(Pinus pinea L.)stands in Spain where we implemented basic individual tree detection with airborne laser scanning ***:We showed how to mimic four different spatial distributions of cut trees using alternative weightings of objective *** Non-spatial selection did not aim at a particular spatial layout,the Single-tree selection dispersed the trees to be cut,and the Tree group and Clearcut selections clustered harvested trees at different ***:The proposed method can be used to control the spatial layout of trees while extracting trees that are the most economically mature.

关键词： Spatial optimization Tree selection Cellular automata Remote sensing Airborne laser scanning

On the Ranks of Semigroups of Transformations on a Finite Set with Restricted Range

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Algebra Colloquium 2014年第3期21卷 497-510页

作者： Vitor H. Fernandes Departamento de Matematica Faculdade de Ciencias e Tebcnologia Universidade Nova de Lisboa Monte da Caparica 2829-516 Caparica Portugal Centro de Algebra da Universidade de lisboa Av. Prof. Gama Pinto 2 1649-003 Lisboa Portugal Department of Mathematics Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand Material Science Research center Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand

Let ΡΥ（X） be the semigroup of all partial transformations on X, Υ（X） and Ι（X） be the subsemigroups of ΡΥ（X） of all full transformations on X and of all injective partial transformations on X, respectively. Given a non-empty subset Y of X, let ΡΥ（X, Y） = {α∈ ΡΥ（X）： Xα Y}, Υ（X, Y） = ΡΥ（X, Y） ∩Υ（X） and Ι（X, Y） = ΡΥ（X, Y） ∩ Ι（X）. In 2008, Sanwong and Sommanee described the largest regular subsemigroup and determined Green＇s relations of Υ（X,Y）. In this paper, we present analogous results for bothΡ Υ（X, Y） and Ι（X, Y）. For a finite set X with ｜x｜≥ 3, the ranks of ΡΥ（X） = ΡΥ（X, X）, Υ（X） = Υ（X, X） and.Ι（X） = Ι（X, X） are well known to be 4, 3 and 3, respectively. In this paper, we also compute the ranks of ΡΥ（X,Y）, Υ（X, Y） and Ι（X, Y） for any proper non-empty subset Y of X.

关键词： transformations restricted range regular elements Green's relations rank

3D-printed aerogels as theranostic implants monitored by fluorescence bioimaging

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Bioactive Materials 2024年第11期41卷 471-484页

作者： Ana Iglesias-Mejuto Rui Pinto Pedro Faísca JoséCatarino João Rocha Luisa Durães Maria Manuela Gaspar Catarina Pinto Reis Carlos A.García-González AerogelsLab I+D Farma Group(GI-1645)Department of PharmacologyPharmacy and Pharmaceutical TechnologyFaculty of PharmacyiMATUS and Health Research Institute of Santiago de Compostela(IDIS)Universidade de Santiago de CompostelaE-15782Santiago de CompostelaSpain Research Institute for Medicines(iMed.Ulisboa) Faculty of PharmacyUniversidade de LisboaAv.Professor Gama Pinto1649-003LisboaPortugal Joaquim Chaves Saúde Joaquim Chaves Laboratório de Análises ClínicasMiraflores1495069AlgésPortugal CECAV-Faculty of Veterinary Medicina-Lusófona university-Lisbon university center Campo Grande 3761749-024LisboaPortugal Faculty of Veterinary Medicina-Lusófona university-Lisbon university center Campo Grande 3761749-024LisboaPortugal university of Coimbra CERES-Chemical Engineering and Renewable Resources for SustainabilityDepartment of Chemical Engineering3030-790CoimbraPortugal Instituto de Biofísica e Engenharia Biomédica(IBEB) Faculdade de CiênciasUniversidade de LisboaCampo Grande1749-016LisboaPortugal

Aerogel scaffolds are nanostructured materials with beneficial properties for tissue engineering *** tracing of the state of the aerogels after their implantation is challenging due to their variable biodegradation rate and the lack of suitable strategies capable of in vivo monitoring the *** nanoparticles(UCNPs)have emerged as advanced tools for in vitro bioimaging because of their fluorescence *** this work,highly fluorescent UCNPs were loaded into aerogels to obtain theranostic implants for tissue engineering and bioimaging applications.3D-printed alginate-hydroxyapatite aerogels labeled with UCNPs were manufactured by 3D-printing and supercritical CO2 drying to generate personalize-to-patient *** physicochemical performance of the resulting structures was evaluated by printing fidelity measurements,nitrogen adsorption-desorption analysis,and different microscopies(confocal,transmission and scanning electron microscopies).Stability of the aerogels in terms of physicochemical properties was also tested after 3 years of *** was evaluated in vitro by different cell and hemocompatibility assays,in ovo and in vivo by safety and bioimaging studies using different murine *** profile,tissue index and histological evaluations of the main organs unveiled an in vivo downregulation of the inflammation after implantation of the ***-decorated aerogels were first-time manufactured and long-term traceable by fluorescence-based bioimaging until 3 weeks post-implantation,thereby endorsing their suitability as tissue engineering and theranostic nanodevices(*** implants).

关键词： Upconversion nanoparticles Aerogels Theranostic implants In vivo fluorescence