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Gold Supported on Metal Oxides for Carb.n Monoxide Oxidation

Nano Research 2011年第2期4卷 180-193页

作者： Sonia A. C. Carab.neiro Nina b.gdanchikova Miguel Avalos-b.rja Alexey Pestryakov pedro b. tavares Jose L. Figueiredo Lab.ratário de Catálise e Materiais Associate Laboratory LSRE/LCM Departamento de Engenharia Química Faculdade de Engenharia Universidade do Porto 4200-465 Porto Portugal Universidad Nacional Autónoma de México Centro de Nanociencias y Nanotecnologia Carretera Tijuana-Ensenada 22800 Ensenada Baja California México Tomsk Polytechnic University 30 Lenin Avenue Tomsk 634050 Russia Universidade de Trás-os-Montes e Alto Douro Centro de Quimica-Vila Real Departamento de Química 5001-911 Vila Real Portugal

Au has b.en loaded （1% wt.） on different commercial oxide supports （CuO, La2O3, Y2O3, NiO） b. three different methods： doub.e impregnation （DIM）, liquid-phase reductive deposition （LPRD）, and ultrasonication （US）. Samples were characterised b. N2 adsorption at -196℃, high-resolution transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectrometry, high-angle annular dark-field imaging （Z-contrast）, X-ray diffraction, and temperature programmed reduction. CO oxidation was used as a test reaction to compare the catalytic activities. The b.st results were ob.ained with Au loaded b. DIM on the NiO support, with an activity of 7.2 × 10^（-4） molco·gAu^（-1）·s^（-1） at room temperature. This is most likely related to the Au nanoparticle size b.ing the smallest in this catalyst （average 4.8 nm）, since it is well known that gold particle size determines the catalytic activity. Other samples, having larger Au particle sizes （in the 2-12 nm range, with average sizes ranging from 4.8 to 6.8 nm）, showed lower activities. Nevertheless, all samples prepared b. DIM had activities （from 1.1 × 10^（-4） to 7.2 × 10^（-4） molco·gAu^（-1）·S^（-1）, at room temperature） ab.ve those reported in the literature for gold on similar oxide supports. Therefore, this method gives b.tter results than the most usual methods of deposition-precipitation or co-precipitation.

关键词： Gold heterogeneous catalysis oxidation electron diffraction X-ray diffraction

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Analysis of a passive ankle exoskeleton for reduction of metab.lic costs during walking

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Defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： Luís Quinto pedro Pinheiro Sergio b.Goncalves Ivo Roupa Paula Simoes Miguel tavares da Silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand sub.tantial physical and psychological exertion,often resulting in fatigue and diminished comb.t or operational *** exoskeletons have b.en developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metab.lic costs during walking,seeking to identify a force element that could b. applied to the target *** on the 6-min walk test,twenty-nine sub.ects participated in the study using three different force *** results indicate that it is possib.e to reduce metab.lic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitab.lity for use in uneven terrain and during extended ***,the choice of the force element should b. tailored to each user,and the control system should b. adjustab.e to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metab.lic cost reduction Dual-use exoskeleton Gait b.omechanics

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Evaluation of Nevirapine Release Kinetics from Polycaprolactone Hyb.ids

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Materials Sciences and Applications 2016年第11期7卷 680-701页

作者： Mariana S. S. b. Monteiro Jackeline Lunz pedro J. Seb.stião Maria Inês b.uno tavares Faculdade de Farmácia Universidade Federal do Rio de Janeiro Centro de Ciências da Saúde Bloco L Cidade Universitária Ilha do Fund&atilde o Rio de Janeiro Brazil Instituto de Macromoléculas Professora Eloísa Mano Universidade Federal do Rio de Janeiro Centro de Tecnologia Bloco J Cidade Universitária Ilha do Fund&atilde o Rio de Janeiro Brazil Departamento de Física Instituto Superior Técnico Technical University of Lisbon Lisbon Portugal

The Nevirapine (NVP)/Polycaprolactone (PCL)/Nanoparticles hyb.ids systems have b.en developed as a potential platform for drug delivery, b. solvent cast, as thin films. NVP, an antiretroviral drug, was included within PCL matrix containing three types of nanoparticles: an organoclay layered silicate Viscogel S7®(3% w/w), hydrophilic silica oxide particles Aerosil®A20 (0.25% w/w) and titanium dioxide particles (0.25% w/w). These systems were characterized b. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), low-field nuclear magnetic resonance (NMR), ultraviolet-visib.e spectroscopy (UV), in-vitro dissolution testing and drug release mechanism kinetics. The PCL crystallization was affected b. NVP incorporation, modifying its semi-crystalline structure to a less ordered structure. When nanoparticles and NVP were added, the Tb.1b.H values increased, for PCL, PCL/S7, PCL/ SiOb.2b. and PCL/TiOb.2b. hyb.ids, suggesting that its addition produced a new material, with less molecular mob.lity, due to the new intermolecular interactions formation. It can consider a structure formation among the PCL chains, nanoparticles and NVP, with strong forces in the PCL/SiOb.2b./NVP system. The amount of NVP included was around 1.5 ± 0.03 mg/cm2. In the in-vitro dissolution test, the PCL/SiOb.2b./NVP system released the smallest amount of drug and this result could b. attrib.ted to the strong intermolecular interaction b.tween the drug and the PCL/SiOb.2b. system. Higuchi’s model was the mathematical model chosen to treat the release data, since this model presented the highest coefficient correlation (r) value. The drug release prob.b.y occur b. diffusion through the matrix pores, thus, these materials are suitab.e for sustained release of NVP.

关键词： Polycaprolactone Nevirapine Hyb.ids Modified Release

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Factors determining the occupancy of nest-b.xes b. Great Tits(Parus major)in eucalypt plantations

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Avian Research 2023年第2期14卷 200-205页

作者： Ricardo S.Ceia pedro b.Lopes Luís Pda Silva Centre for Functional Ecology–Science for People&the Planet Department of Life SciencesUniversity of Coimbra3000-456CoimbraPortugal CIb.O Centro de Investigaçao em Biodiversidade e Recursos GeneticosInBIO Laboratorio AssociadoCampus de Vair aoUniversidade do Porto4485-661VairaoPortugal b.OPOLIS Program in Genomics Biodiversity and Land PlanningCIBIOCampus de Vai~ao4485-661VairaoPortugal

Providing nest-b.xes as surrogate tree cavities can b. of great importance to increase the b.eeding populations of cavity-nesting b.rds in managed ***,the exact placement of nest-b.xes should b. taken into consideration to enhance their occupancy according to species-specific *** this study,we investigated which factors can b.tter predict nest-b.x occupancy b. the Great Tit(Parus major)in eucalypt *** used generalised linear mixed-effects models to analyse the influence of topography,nest-b.x positioning,vegetation cover and landscape variab.es on three-year occupancy records from 80 newly provided ***-random patterns of nest-b.x occupancy were found with respect to all categories except *** suggest that Great Tits prefer to occupy high-placed nest-b.xes,close to areas that can provide them with supplementary resources either within or in the vicinity of the stand(i.e.,trees other than eucalypts,riparian vegetation,and large patches of adjacent hab.tats).Overall,this study provides important recommendations for nest-b.x placement and spatial distrib.tion in managed forests and enhances the potential of nest-b.x interventions as a b.odiversity offset and management tool.

关键词： Eucalyptus glob.lus Managed forest Nest-site attrib.tes Secondary cavity-nester Species-specific preferences Tit

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Deadly oasis:Recurrent annihilation of Cretaceous desert b.yophyte colonies;the role of solar,climate and lithospheric forcing

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Geoscience Frontiers 2021年第1期12卷 1-12页

作者： Juan pedro Rodríguez-Lópeza Eduardo b.rrón Daniel Peyrot Gary b.Hughes Department of Geology.Faculty of Science.United Arab.Emirates University.50009.Al Ain Abu DhabiUnited Arab Emirates Instituto Geológico y Minero de Espana(IGME) Ríos Rosas 23E-28003MadridSpain School of Earth and Environment University of Western Australia.6101CrawleyWestern AustraliaAustralia Centre for Energy Geosciences University of Western Australia.6101CrawleyWestern AustraliaAustralia Physics Department University of CaliforniaSanta BarbaraCA93106USA

Many oases(wet interdunes)are sedimentary systems characterized b. high-frequency water-level oscillations,marked changes in salinity and intense b.ological activity at their *** are considered to b. one of the most challenging environments on Earth for ecosystem *** dynamic,depositional settings are usually unfavourab.e for fossilization and sub.equent preservation of vegetal *** paper describ.s b.yophyte(liverwort)assemb.ages occurring in three successive horizons interpreted to represent(i)recurrent early successional phases of b.ological soil crust colonization of wet interdune margins or(ii)exceptional preservation of floating or riparian liverworts in oasis pond waters associated with a progressive fall of the interdune water *** record of in situ colonization surfaces characterized b. delicate(***-free)three-dimensional structures represents an exceptional type of preservation herein associated with a rapid variation in phreatic interdune water level and the sub.equent estab.ishment of anoxic and reducing *** occurrence of exceptionally preserved liverwort colonies coincides with the sedimentary record of,at least,three seismite levels in the *** gathered from the site suggests that the water tab.e of the oasis was controlled b. a comb.nation of(i)a positive creation of accommodation space due to sub.idence associated with movement on syn-sedimentary extensional faults,and(ii)the rise and fall of the oasis water tab.e controlled b. the oscillations of the groundwater system due to orb.tal changes which appear to drive the variab.lity of the climate *** groundwater levels flooded the oasis soil crusts and lead to the exceptional recurrent preservation of liverwort colonies at the oasis ***,considering the hypothesis of floating or riparian liverworts in the oasis pond waters,the fall in the level of the oasis water tab.e placed the floating liverworts in contact with the

关键词： Oasis Cretaceous Liverworts Colonies Extensional tectonics Solar cyclicity

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Post Secondary Students’ Level of Proficiency in Solving Real World Prob.ems in Mathematics

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Journal of Applied Mathematics and Physics 2018年第1期6卷 198-214页

作者： Lorinda E. Pascual Anthony b. San pedro College of Engineering Nueva Ecija University of Science and Technology Cabanatuan City Philippines Department of Pub.ic Administration Nueva Ecija University of Science and Technology Cabanatuan City Philippines

The prob.em solving competency is the primary goal in all mathematics education curricula. It is acquired b. solving mathematical prob.ems b.longing either to routine or non-routine category. The study describ.s the post-secondary students’ levels of proficiency in solving non-routine math prob.ems. The three-stage process in solving mathematics prob.ems b. Mayer was used as the frame of analysis. Using the data generated from researcher made instruments, and semi-structured interview of 50 purposively selected participants, the study found that: Majority of the participants showed “good proficiency” in “prob.em representation” and “prob.em solving”, the real world prob.ems in Math. It is also revealed that those who are good in prob.em representation phase are also good in prob.em solution phase. In general, participants do not always consider answer verification phase as important in the process of solving real world prob.ems in math. The most common difficulties encountered b. participants are: language inadequacy and unfamiliarity with the context of the prob.ems. The researchers recommended that the same study b. done in some other context and local and if the results are consistent with this study, may consider redesigning new curriculum in post-secondary mathematics education.

关键词： Mathematics Post-Secondary Students Prob.em Solving

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Quantitative morphometric analysis of the Jama River profile in a tectonically active margin (Northwestern Ecuador)

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Journal of Mountain Science 2018年第5期15卷 966-975页

作者： pedro S.b. REYES Mauricio E. VALAREZO Jenry CORDOVA Francois A. MICHAUD Camilo ZAPATA Department of Geology Escuela Politécnica Nacional Ladrón de Gueuara E11-253 PO.Box 17-01-2759 Quito Ecuador C-eostrat S.A. Jorge Drom N39-188y Gaspar de Villaroel Quito Ecuador Department of Civil and Environmental Engineering Escuela Politécnica National Ladrón de Guevara E11-253 PO.Box17-ol-2759 Quito Ecuador Sorb.nne Université Université Cote d'Azur IRD CNRS Observatoire de la Cdte d'Azur C-eoazur 250 rue A. EinsteinSophia Antipolis 06560 Valbonne France

The longitudinal profile of a river channel can b. describ.d in function of mathematical expressions. The logarithmic fit is the most used method to describ. the relative equilib.ium of a channel elevation profile. Rivers showing zones of high channel gradient and convex-upward profiles can b. evaluated in function of the offset distance with respect to the logarithmic curve. The Jama River profile has b.en constructed using differential GPS data for the downstream reach and 4-m-grid DEM data b.se for the remaining headward profile. The resulting longitudinal profile shows a prominent knickpoint of ab.ut 80 m in elevation characterized b. sharp local convexity. The offset distance in vertical direction from the logarithmic plot is interpreted as the successive accumulation of multiple uplift episodes associated with the Jama Fault System activity. The horizontal offset is suggested to represent the remaining retreated distance for the upstream propagation of the Jama knickpoint. The highly resistant Cretaceous rocks outcropping along the Jama knickpoint reach acts as an inflection point b.tween two sub.rofiles that show well-fitted logarithmic curves, thereb. representing a temporary partitioned equilib.ium along the Jama River profile.

关键词： Morphometry Jama River Stream profile Active tectonics

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Influence of Organoclay Structure on Nanostructured Materials b.sed on Eva

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Materials Sciences and Applications 2015年第10期6卷 860-868页

作者： Gisele C.V.Iulianelli pedro Jose Oliveira Seb.stiao Maria Ines b.tavares Fernanda Ab.ate dos Santos Instituto de Macromoleculas Professora Eloisa Mano da Universidade Federal do Rio de Janeiro(IMA/UFRJ) Centro de TecnologiaBloco JIlha do FundaoRio de JaneiroRJ CEP:21941-598Brazil Condensed Matter Physics Centre University of LisbonLisbonPortugal Departamento de Fisica Instituto Superior TecnicoTechnical University of LisbonLisbonPortugal

This article reports the preparation of a series of EVA nanocomposites employing solution casting methods using different types of organo-modified montmorillonite clay. The effect of the organoclay type on the structural organization and thermal b.havior of EVA nanostructured materials were systematically investigated. Regarding thermal b.havior, the thermogravimetric analysis showed that the nanocomposites presented a slight decrease in thermal degradation temperature compared to EVA, while differential scanning calorimetry, in general, did not show a significant change in the thermal transition temperatures such as glass transition, melting temperature and crystallization temperature of the nanocomposites, regardless of the type and proportion of organoclay in the systems. With respect to structural aspect, the X-ray diffractograms showed that all systems presented a heterogeneous distrib.tion of the nanoparticles, containing part intercalated. Nuclear magnetic resonance relaxometry data provided complementary information for the X-ray results, showing that the EVA systems containing 5 wt% of b.th studied organoclays presented a mixture of intercalated and exfoliated structures, evidencing that there was a surface interaction b.tween polymer chains and clay lamellae.

关键词： EVA Nanocomposites NMR Relaxometry

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Effect of the Coulomb.and dielectric forces on the onset of Rayleigh-b.nard convection

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Acta Mechanica Sinica 2024年第6期40卷 64-77页

作者： Zhonglin Du pedro A.Vázquez Jian Wu School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China Heilongjiang Key Lab.ratory of Micro-and Nano-scale Fluid Flow and Heat Transfer Harbin150001China Departamento de Física Aplicada III ETSIIUniversidad de SevillaSevilla41092Spain

In this paper,the effect of Coulomb.and dielectric forces on the onset of Rayleigh-b.nard convection(Rb.)in a dielectric liquid layer contained b.tween two parallel electrode plates has b.en numerically *** different operating conditions have b.en considered in electrohydrodynamic(EHD)conduction:ohmic and saturation,and variations in the physical properties of the dielectric fluid with *** electric equations and the state equations b.sed on the b.ussinesq approximation are integrated in the framework of OpenFOAM b.oyantb.ussinesqPimpleFoam *** results show that in the ohmic regime,the comb.ned effect of Coulomb.and dielectric forces promotes the onset of Rb. flow,while in the saturation state,the inhib.tion of Rb. flow b. Coulomb.force is more *** value of the critical Rayleigh numb.r Ra decreases with increasing electric Reynolds numb.r ReE in the ohmic regime,whereas in the saturation state,the critical Ra increases with increasing *** the saturation regime,the flow field always has a steady flow in the range of parameters ***,the onset of the Rb. flow promoted b. the dielectric force is more pronounced in the ohmic *** to the presence of the dielectric force,the flow field exhib.ts periodic oscillatory flow at low electric Reynolds numb.rs for the range of parameters considered.

关键词： EHD conduction Dielectric force Rayleigh-b.nard convection OpenFOAM

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Chromate and the Environment： Removal and Utilization of Industrial Waste

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Journal of Chemistry and Chemical Engineering 2016年第3期10卷 147-152页

作者： Femando b. Mainier pedro Paulo b. Leite Marcone F. Reis Thiago Teob.ldo Silva Engineering School Federal Fluminense University(UFF) Niteroi Rio de Janeiro 24220-261 Brazil

Chromate and dichromate sodium as a function of oxidizer characteristics are used in several industrial areas; for example, in surface protection of coated parts of cadmium, zinc and aluminum （chromate coated treated）, corrosion inhib.tors, the treatment of leather, the manufacture of pigments, etc. However, the use of such products has b.en questioned due to the prob.ems of toxicity and pollution that can b. caused in the environmental. The b.azilian environmental agency has estab.ished that the concentrations of chromate in water courses are less than 0.5 ppm. In order to reuse chromate （CrO42） from industrial effluent, lab.ratory experiments have b.en proposed b.sed on chemical reduction or electrolytic processes, in order to transform these chromate ions in a final mix of oxides （in solid form）, which can then b. packed and sent to the production process of sodium chromate. The results of these experiments have b.come useful industrially （without regard to costs） considering the environmental reuse and the life cycle of the chemical compound.

关键词： Chromate dichromate contamination chemical reduction electrolytic process.

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