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New Nanocomposite Materials by Incorporation of Nanocrystalline TiO_2 Particles into Polyaniline conductive Films

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Journal of Materials Science & Technology 2014年第5期30卷 449-454页

作者： F.J.Feliciano O.c.monteiro Department of chemistry and Biochemistry and cQB Faculty of SciencesUniversity of LisbonCampo Grande1749-016 LisbonPortugal

This work is focused on the combination of two building-blocks, nanocrystalline TiO2 particles and polyaniline conductive films （PAni）. The preparation of new nanostructured composite materials, displaying electron- and proton-conductive properties, to be used for the fabrication of new and superior energy storage devices was envisaged. The semiconducting TiO2 nanoparticles were obtained by means of a hydrothermal route. The PAni films were prepared on glassy carbon electrodes by electrochemical polymerization, under potential dynamic conditions. After characterization by X-ray diffraction, transmission electron microscopy or scanning electron microscopy and electrochemical techniques, the nanocrystalline particles were immobilized in the polymer matrix. The incorporation of the TiO2 was achieved using two distinct approaches： during the polymer growth or by deposition over previously prepared PAni films. The results demonstrate that the PAni morphology depends on the experimental conditions used during the polymer growth. After TiO2 immobilization, the best electrochemical response was obtained for the nanocomposite structure produced through the TiO2 incorporation after the PAni film synthesis. The modified electrodes were structurally and morphologically characterized and their electro-catalytic activity towards the hydrogen evolution reaction was analyzed. A new electrochemical performance related with the oxidation of molecular hydrogen entrapped in the PAni-TiO2 matrix was observed for the modified electrode after TiO2 incorporation. This behavior can be directly associated with the synergetic combination of the TiO2 and PAni, and is dependent on the amount of the semiconductor.

关键词： PolyaniHne (PAni) Nanosized TiO2 Nanocomposites Hydrogen trapping

Titanate Nanorods Modified with Nanocrystalline ZnS Particles and Their Photocatalytic Activity on Pollutant Removal

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Journal of Materials Science & Technology 2016年第11期32卷 1122-1128页

作者： G.Naudin T.Entradas B.Barrocas O.c.monteiro Faculte de chimie Universite Pierre et Marie Curie (UPMC) Batiment F 3e etage 4 placeJussieu 75005 Paris France centro de Quimica e Bioquimica Faculdade de Ciencias Universidade de Lisboa 1749-016 Lisboa Portugal

Aiming to produce materials with enhanced photocatalytic properties, the synthesis of new crystalline nanocomposites by combining titanate nanorods（TNR） with ZnS nanocrystallites is described in this *** TNR modification was accomplished by an in situ nucleation and growth process of ZnS *** diethyldithiocarbamate was used as the metal chalcogenide precursor. The prepared materials were structural, morphological and optical characterized by X-ray diffraction, transmission electron microscopy and high resolution transmission electron microscopy, energy dispersive spectroscopy and powder diffuse reflectance spectra. crystalline Zn S nanoparticles were obtained as a homogeneous and continuous layer, covering completely the TNR surface. The application of these new nanocomposite materials on photocatalytic degradation of pollutants was investigated. First, the evaluation of hydroxyl radical formation, using the terephthalic acid as probe, was studied. Afterwards, the adsorption and photodegradation of safranine-T, used here as a model pollutant molecule, was investigated. The obtained data indicate that the prepared nanocomposites have potential to be used as photocatalysts for organic pollutant *** best removal results（97% removal） were obtained using the 0.01 Zn S/HTNR sample as catalyst（0.2 g/L; 10 ppm safranin-T solution） with a combination of a low dye adsorption（20%） and a high dye photocatalytic degradation（77%）.

关键词： Nanocomposite materials Surface modification Photocatalysis Adsorption ability Optical properties

A comparative study on emergent pollutants photo-assisted degradation using ruthenium modified titanate nanotubes and nanowires as catalysts

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Journal of Environmental Sciences 2020年第6期32卷 38-51页

作者： Beatriz Barrocas M.conceicao Oliveira Helena I.S.Nogueira Sara Fateixa Olinda c.monteiro centro de Química Estrutural Faculdade de CienciasUniversidade de LisboaLisboa 1749-016Portugal centro Química Estrutural Instituto Superior TécnicoUniversidade de LisboaLisboa 1049-001Portugal Department of chemistry CICECO-Aveiro Institute of MaterialsUniversity of AveiroAveiro 3810-193Portugal

Several methods have been used to tailor nanomaterials structure and ***,slight changes in the structure outcomes expressive improvements in the optical and photocatalytic properties of semiconductor *** this context,the influence of the metal doping and the morphology on a catalyst performance was studied in this ***,ruthenium doped titanate nanotubes(RuTNT)were synthesised for the first time using an amorphous Ru-containing ***,the photocatalytic performance of this sample was compared to the one obtained for ruthenium titanate nanowires(RuTNW),recently *** samples,RuTNW and RuTNT,were produced using the same Ru-containing precursor but distinct hydrothermal *** powders were structural,morphological and optical characterized by X-ray diffraction and fluorescence,transmission electron microscopy,Raman,X-ray photoelectron and photoluminescence *** variations on the structural and optical properties of the RuTNT and RuTNW nanoparticles,due to ruthenium incorporation were *** potential use as photocatalysts was evaluated on the hydroxyl radical photo-assisted *** samples were catalytic for this reaction,presenting better performances than the pristine counterparts,being RuTNT the best ***,the degradation of two emergent pollutants,caffeine and sulfamethazine,was *** demonstrated to be better photocatalyst than RuTNW for caffeine but identical performances were obtained for *** both catalysts,the degradation mechanism of the pollutants was explored through the identification and quantification of the intermediate compounds produced and several differences were *** indicates the importance of the structural and morphological aspects of a material on its catalytic performance.

关键词： Titanate nanotubes and nanowires Ruthenium doping Ru-Ti replacement Emergent pollutants Photocatalytic degradation

Hydrocarbons in particulate samples from wildfire events in central Portugal in summer 2010

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Journal of Environmental Sciences 2017年第3期29卷 122-131页

作者： Ana Vicente Ana calvo Ana P.Fernandes Teresa Nunes cristina monteiro casimiro Pio célia Alves centre for Environmental and Marine Studies (cESAM) Department of EnvironmentUniversity of Aveiro Department of Physics IMARENABUniversity of León

In summer 2010, twenty eight （14 PM=2.5 samples plus 14 samples PM2.5-10） smoke samples were collected during wildfires that occurred in central Portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse （PM=2.5-10） and fine （PM2.5） smoke samples. The carbonaceous content （elemental and organic carbon） of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatog- raphy into three different classes of organic compounds （aliphatics, polycyclic aromatic hydrocarbons （PAHs） and carbonyl compounds）. The organic speciation was performed by gas chromatography-mass spectrometry （Gc-MS）. Emissions were dominated by the fine particles, which represented around 92% of the PM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon （Oc/Ec） ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between Oc and both aliphatic and PAH compounds. Pyrogenic processes, thermal release of biogenic com- pounds and secondary processing accounted for 97% of the apportioned PM2.5 levels.

关键词： WildfiresOrganic carbonOrganic compoundsBiomarkersParticulate matterPortugal

Degradation of duloxetine: Identification of transformation products by UHPLc-ESI(+)-HRMS/MS,in silico toxicity and wastewater analysis

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Journal of Environmental Sciences 2019年第8期31卷 113-123页

作者： Rodrigo A.Osawa Ana P.carvalho Olinda c.monteiro M.conceicao Oliveira M.Helena Florêncio centro de Química e Bioquímica Faculdade de Ciências Universidade de Lisboa Laboratório de FTIcR e Espectrometria de Massa Estrutural Faculdade de Ciências Universidade de Lisboa centro de Química Estrutural Instituto Superior Técnico Universidade de Lisboa

Duloxetine(DUL), an antidepressant drug, has been detected in surface water and wastewater effluents, however, there is little information on the formation of its transformation products(TPs). In this work, hydrolysis, photodegradation(UV irradiation) and chlorination experiments were performed on spiked distillated water, under controlled experimental conditions to simulate abiotic processes that can occur in the environment and wastewater treatment plants(WWTPs). Eleven TPs, nine from reaction with UV light and two from chlorine contact, were formed and detected by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry, and nine of them had their chemical structures elucidated upon analyses of their fragmentation patterns in MS/MS spectra. The formation and degradation of the TPs were observed. The parent compound was completely degraded after30 min in photodegradation and after 24 hr in chlorination. Almost all TPs were completely degraded in the experiments. The ecotoxicity and mutagenicity of the TPs were predicted based on several in silico models and it was found that a few of these products presented more ecotoxicity than DUL itself and six TPs showed positive mutagenicity. Finally, wastewater samples were analyzed and DUL and one TP, possibly formed by chlorination process, were detected in the effluent, which showed that WWTP not only did not remove DUL, but also formed a TP.

关键词： High resolution mass spectrometry Duloxetine Degradation processes Transformation products Wastewater analysis In silico toxicity

Light meson spectrum and their leptonic decay widths in the frame work of constituent quark models

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chinese Physics c 2010年第9期34卷 1396-1398页

作者： K.B.Vijaya Kumar Antony Prakash monteiro Department of Physics Mangalore University

The phenomenological non-relativistic quark model has been employed to obtain the ground state masses of light vector mesons and their radially excited states and their decay *** full hamiltonian used in the investigation has kinetic energy,the confinement potential and the one-gluon-exchange potential.A good agreement is obtained with the experimental masses and their leptonic decay widths.

关键词： meson spectrum leptonic decay width constituent quark model OGEP

Effect of Alloying Additions on the Oxidation of High Speed Steels under Dry and Wet conditions

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中国腐蚀与防护学报 2009年第4期29卷 241-247页

作者： F. c. RIZZO M. J. monteiro S. R. J. SAUNDERS DcMM PUC Rio de Janeiro Brazil Bentley Surrey UK

An investigation has been carried out into the effects of chromium and vanadium content on the oxidation rate and on the adhesion of oxide scales grown on three different chemical compositions of high speed steels under dry and wet *** oxidation tests were carried out in a thermobalance at 650℃for up to 14.4 *** mass gain of the specimens increased with increasing contents of water vapour. Alloy composition had no effect on the oxidation rate in dry ***'adhesion'of the oxide scale was determined using indentation with a Rockwell c diamond and the pull adhesion test to determine the interfacial toughness and the tensile strength of the oxide metal bond,***,the results of the investigation indicated that oxide adhesion was lowest for the specimens exposed to dry conditions, and that with increasing water vapour content,the scale was more *** test results showed that an increase in the V concentration was deleterious to oxide adhesion in both the dry and wet environments,whereas an increase in the cr-content had little effect on adhesion.

关键词：合金腐蚀氧化金属材料

Heavy quarkonia spectra and their decays in a relativistic quark model

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chinese Physics c 2011年第11期35卷 997-1003页

作者： Bhaghyesh K. B. Vijaya Kumar Antony Prakash monteiro Department of Physics Mangalore University

Using the phenomenological relativistic harmonic model （RHM） for quarks, we have obtained the masses of S wave charmonium and bottomonium states. The full Hamiltonian used in the investigation has Lorentz scalar plus vector confinement potential, along with the confined one gluon exchange potential （cOGEP）. A good agreement with the experimental masses for the ground and the radially excited states is obtained both for the triplet and singlet S wave mesons. The decay properties of the ground state charmonium and bottomonium are investigated.

关键词： relativistic harmonic model confined one gluon exchange potential S-wave spectrum decay rates

Posterior partially edentulous jaws, planning a rehabilitation with dental implants

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World Journal of clinical cases 2015年第1期3卷 65-76页

作者： Douglas R monteiro Emily V F Silva Eduardo P Pellizzer Osvaldo Magro Filho Marcelo c Goiato Department of Dental Materials and Prosthodontics Araçatuba Dental SchoolUniv Estadual Paulista(UNESP)São Paulo 16015-050Brazil

AIM: To discuss important characteristics of the useof dental implants in posterior quadrants and the rehabilitation planning. METHODS: An electronic search of English articles was conducted on MEDLINE(PubM ed) from 1990 up to the period of March 2014. The key terms were dental implants and posterior jaws, dental implants/treatment planning and posterior maxilla, and dental implants/treatment planning and posterior mandible. No exclusion criteria were used for the initial search. clinical trials, randomized and non randomized studies, classical and comparative studies, multicenter studies, in vitro and in vivo studies, case reports, longitudinal studies and reviews of the literature were included in this review. RESULTS: One hundred and fifty-two articles met the inclusion criteria of treatment planning of dental implants in posterior jaw and were read in their entirety. The selected articles were categorized with respect to their context on space for restoration, anatomic considerations(bone quantity and density), radiographic techniques, implant selection(number, position, diameter and surface), tilted and pterygoid implants, short implants, occlusal considerations, and success rates of implants placed in the posterior region. The results derived from the review process were described under several different topic headings to give readers a clear overview of the literature. In general, it was observed that the use of dental implants in posterior region requires a careful treatment plan. It is important that the practitioner has knowledge about the theme to evaluate the treatment parameters. cONcLUSION: The use of implants to restore the posterior arch presents many challenges and requires a detailed treatment planning.

关键词： Dental implants Mandible Maxilla Edentulous jaw Treatment