Publications

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2015
Tolstogouzov, A. B., S. F. Belykh, V. S. Gurov, A. A. Lozovan, A. I. Taganov, O. M. N. D. Teodoro, A. A. Trubitsyn, and S. P. Chenakin. "Ion Beam Sources Based on Room Temperature Ionic Liquids for Aerospace Applications , Nanotechnology , and Microprobe Analysis ( Review )." Instruments and Experimental Techniques. 58.1 (2015): 1-14.2014_review_ion_beam_sources.pdf
2013
and Ana L. Fonseca, A. Marta Barreto, Sofia Matos A.M.C.Moutinho Orlando M.N.D.Teodoro A. Calibration of reference leaks in a wide pressure range. PTDC/EME-MFE/098738/2008., 2013.15_2013_ivc19.pdf
Fonseca, Ana Luísa Caracterização de microfluxos: medição, geração e calibração. Eds. Orlando M. N. D. Teodoro. Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa. CAPARICA: FCT/UNL, 2013.9_2013_ana_fon.pdf
de Batista, Tiago Afonso Brito Construção e Caracterização de fugas de referência de gases frigorigéneos. Eds. Orlando M. N. D. Teodoro. Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa. CAPARICA: FCT/UNL, 2013.8_2013_tiago_bat.pdf
Bundaleski, N., J. Trigueiro, A. G. Silva, A. M. C. Moutinho, and O. M. N. D. Teodoro. "Influence of the patch field on work function measurements based on the secondary electron emission." JOURNAL OF APPLIED PHYSICS. 113.183720 (2013): 1-11.2013_influence_of_the_patch_field_on_work_function_measurements_based_on_the_secondary_electron_emission.pdf
Bundaleski, Nenad, Stefano Caporali, Sergey P. Chenakin, Augusto M. C. Moutinho, Orlando M. N. D. Teodoro, and Alexander Tolstogouzov. "Ion-induced fragmentation of imidazolium ionic liquids : TOF-SIMS study." International Journal of Mass Spectrometry. 353 (2013): 19-25.2013_ion-induced_fragmentation_of_imidazolium_ionic_liquids.pdf
Brazinha, Carla, Ana P. Fonseca, Helena Pereira, and Orlando M. N. D. Teodoro. "{Gas transport through cork: Modelling gas permeation based on the morphology of a natural polymer material}." Journal of membrane science. 428 (2013): 52-62. Abstract2013_gas_transport_through_cork-_modelling.pdf

Natural polymers have been studied during the last years for the transport and separation of liquid and gas mixtures, in terms of solubility and permeability data, and their structure and mechanical properties have been characterised. However, no transport models have been reported, relating transport with the material morphology. Cork is a natural cellular material containing three structural polymers (suberin, lignin and polysaccharides). Cork is considered a natural polymer, with economic relevance due to its sealing, non-toxic, stable and low-density properties. Corkwas characterised in this work in terms of its solubility and permeability data in relation to various gases with different molecular mass: He, O2,N2,CO2 and 1,1,1,2-tetrafluoroethane (R134a). A morphological analysis of the structure of the cork sample chosen in this work was also performed using SEM (scanning electron microscopy) and TEM (transmission electron microscope) image analysis, which took into account the variation of each relevant structural parameter. A transport model was developed supported on the morphology of cork characterised in this work. The transport model developed considers that gas permeation occurs through the plasmodesmata, which are channels with approximately 100 nm of diameter that cross the cell walls of the cork cells. It was found that gas transport follows a Knudsen mechanism, as proved by the gas permeability behaviour with increasing gasmolecularmass, with a negligible contribution of viscous transport to the total flux. &

Fonseca, Ana Luisa, Carla Brazinha, Helena Pereira, Joao G. Crespo, and Orlando M. N. D. Teodoro. "{Permeability of Cork for Water and Ethanol.}." Journal of agricultural and food chemistry. 61 (2013): 9672-9679. Abstract2013_permeability_of_cork_for_water_and_ethanol.pdfWebsite

Transport properties of natural (noncompressed) cork were evaluated for water and ethanol in both vapor and liquid phases. The permeability for these permeants has been measured, as well as the sorption and diffusion coefficients. This paper focuses on the differences between the transport of gases' relevant vapors and their liquids (water and ethanol) through cork. A transport mechanism of vapors and liquids is proposed. Experimental evidence shows that both vapors and liquids permeate not only through the small channels across the cells (plasmodesmata), as in the permeation of gases, but also through the walls of cork cells by sorption and diffusion as in dense membranes. The present study also shows that cork permeability for gases was irreversibly and drastically decreased after cork samples were exposed to ethanol or water in liquid phase.

Gawande, Manoj B., Anuj K. Rathi, Paula S. Branco, T. M. Potewar, Alexandre Velhinho, Isabel D. Nogueira, Alexander Tolstoguzov, Amjad C. A. Ghumman, and Orlando M. N. D. Teodoro. "{Nano-MgO-ZrO2 Mixed Metal oxides: Characterization by SIMS and application in the reduction of carbonyl compounds and in multicomponent reactions}." RSC Advances. 3 (2013): 3611-3617. Abstract

A nano-sized Magnesia–Zirconia (nano-MgO–ZrO2) catalyst was prepared by a simple ultradilution co-precipitation method and by using inexpensive precursors. The nano-MgO–ZrO2 was extensively characterized by SIMS together with other analytical techniques such as X-ray diffraction (XRD) and transmission electron microscopy (TEM). The nano-MgO–ZrO2 catalyst proved to be very efficient for the reduction of carbonyl compounds and multicomponent reactions under mild reaction conditions. The recyclability and reusability of the nano-MgO–ZrO2 catalyst has been tested.

a. a. Ghumman, C., M. C. a. Moutinho, A. Santos, A. Tolstogouzov, and O. M. N. D. Teodoro. "{TOF-SIMS VG Ionex IX23LS: upgrade and application for the urinary stones analysis}." Surface and Interface Analysis. 45 (2013): 532-536. AbstractWebsite
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2012
A.P. Fonseca, T. Batista, Teodoro O. M. N. D. DESIGN AND CHARACTERIZATION OF REFRIGERANT REFERENCE LEAKS. PTDC/EME-MFE/098738/2008., 2012.13_2012_evc12.pdf
Brazinha, C., A. P. Fonseca, H. Pereira, O. M. N. D. Teodoro, and J. G. C. Crespo. "Modelling gas permeation based on the morphology of a natural polymer material." Procedia Engineering. Vol. 44. 2012. 529-531. Abstract2012_modelling_gas_permeation.pdf

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Teodoro, Orlando M. N. D. Vacuum Physics Applied to the Transport of Gases Through Cork. PTDC/EME-MFE/098738/2008., 2012.14_2012_vass.pdf
Gawande, Manoj B., Alexandre Velhinho, Isabel D. Nogueira, C. A. A. Ghumman, O. M. N. D. Teodoro, and Paula S. Branco. "{A facile synthesis of cysteine – ferrite magnetic nanoparticles for application in multicomponent reactions — a sustainable protocol}." RSC Advances. 2 (2012): 6144-6149. Abstract

A facile, simple and environmentally friendly Fe3O4–cysteine MNP was synthesized without any additive or additional source of linkers. Fe3O4–cysteine MNPs were successfully used for the synthesis of b-amino carbonyl and hydroquinoline compounds, which were obtained in excellent yields via multicomponent reactions. Magnetic organocatalysts can be easily recovered by simple magnetic decantation and their catalytic activity remains unaltered after 9 consecutive cycles, making them environmen- tally friendly and widely applicable due to their efficiency, ease of handling, and cost effectiveness.

Gawande, Manoj B., Anuj Rathi, Isabel D. Nogueira, C. a. a. Ghumman, N. Bundaleski, O. M. N. D. Teodoro, and Paula S. Branco. "{A Recyclable Ferrite-Co Magnetic Nanocatalyst for the Oxidation of Alcohols to Carbonyl Compounds}." ChemPlusChem. 77 (2012): 865-871. AbstractWebsite
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Ghumman, C. A. A., A. M. C. Moutinho, A. Santos, O. M. N. D. Teodoro, and A. Tolstogouzov. "{An upgraded TOF-SIMS VG Ionex IX23LS : Study on the negative secondary ion emission of III – V compound semiconductors with prior neutral cesium deposition}." Applied Surface Science. 258 (2012): 2490-2497. Abstract

A TOF-SIMS VG Ionex IX23LS with upgraded data acquisition and control system was used to study the secondary emission of negative atomic and cluster ions of non-metallic elements (P, As and Sb) upon a 19 keV Ga+ bombardment of non-degenerated III–V semiconductors (GaP, GaAs, GaSb, InP, InAs and InSb) with prior neutral Cs deposition from a getter dispenser. It was found that surface cesiation enhances the peak intensity of all negative ion species; in the case of atomic ions, the greatest increase (360) was observed for P− emitted from InP. Such an enhancement was larger for In-based than for Ga-based compounds. We explained that in terms of an electronegativity difference between the composing atoms of III–V semiconductors. The greater electronegativity difference (bond ionicity) of In-based compounds resulted in the greater Cs-induced work function decrease leading to a higher increase in the ionization probability of secondary ions.

Neto, M. a, E. L. Silva, C. a Ghumman, O. M. Teodoro, A. J. S. Fernandes, F. J. Oliveira, and R. F. Silva. "{Composition profiles and adhesion evaluation of conductive diamond coatings on dielectric ceramics}." Thin Solid Films. 520 (2012): 5260-5266. AbstractWebsite

Sintered silicon nitride (Si3N4) ceramic substrates were investigated as dielectric substrates for the growth of metal-like boron-doped nanocrystalline diamond (NCD) and microcrystalline diamond coatings via the Hot Filament Chemical Vapor Deposition (HFCVD) technique. The structural, electrical and chemical properties of both the ceramic substrates and the diamond coatings may potentiate their applicability in particular in harsh environments and highly demanding situations. Boron doping was achieved via a boron oxide solution in ethanol dragged into the reaction chamber with argon. The coatings were characterized by scanning elec- tron microscopy, UV $μ$-Raman scattering, X-ray diffraction, time-of-flight secondary ion mass spectroscopy, Brale indentation for adhesion evaluation and two-point contact probe for resistivity measurements. The HFCVD technique led to a maximal growth rate of about 1 $μ$m/h. Several metal-like boron doped diamond coatings were obtained. It was found that at lower substrate temperature, lower system pressure and higher methane concentration, the resistivity of the conducting NCD coatings is about 3 orders of magnitude higher when compared with samples obtained with higher substrate temperature, higher system pressure and lower methane concentration. Nevertheless, for every metal-like boron-doped coating the use of the Si3N4 ceramic substrate guaranteed a superior adhesion level. ©

Silva, Ana G., Nenad Bundaleski, Augusto M. C. Moutinho, and Orlando M. N. D. Teodoro. "{Dynamics of water adsorption on TiO 2 monitored by work function spectroscopy}." Applied Surface Science. 2 (2012): 2006-2009. Abstract

Water adsorption dynamics on two TiO2 (1 1 0) rutile surfaces at room temperature has been investigated using the work function (WF) change as a function of time. The first surface was prepared in a standard way using sputtering/annealing cycles, whereas the second one was long term annealed at 620 K in moderate vacuum conditions (the residual gas pressure of about 1 × 10−7 mbar) and cleaned afterwards. The WF change show striking difference as compared to those obtained for highly reduced TiO2 (1 1 0) rutile or the (2 × 1) reconstructed surfaces. For the first kind of surface we show that the observed adsorption dynamics can be qualitatively explained by the present understanding of the water adsorption on non- reconstructed TiO2 (1 1 0) rutile surface according to which the bridging oxygen vacancies and Ti rows are the main adsorption sites. Although generally similar to the former results, water adsorption dynamics on the second kind of the surface has an additional feature that can be only explained by a new adsorption site, which we suggest to be due to (2 × 1) reconstructed regions coexisting with the non-reconstructed TiO2 (110)surface.

Santos, Adérito, Nenad Bundaleski, Bobbie-jean Shaw, Ana G. Silva, and Orlando M. N. D. Teodoro. "{Increase of secondary electron yield of amorphous carbon coatings under high vacuum conditions}." Vaccum (2012): 1-4. AbstractWebsite
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Gawande, Manoj B., Anuj K. Rathi, Paula S. Branco, Isabel D. Nogueira, Alexandre Velhinho, Janhavi J. Shrikhande, Utkarsha U. Indulkar, Radha V. Jayaram, Amjad C. A. Ghumman, Nenad Bundaleski, and Orlando M. N. D. Teodoro. "{Regio- and Chemoselective Reduction of Nitroarenes and Carbonyl Compounds over Recyclable Magnetic Ferrite À Nickel Nanoparticles ( Fe 3 O 4 À Ni ) by Using Glycerol as a Hydrogen Source}." Chemistry European Journal (2012): 12628-12632. Abstract
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Alberti, M., R. Ayouchi, S. R. Bhattacharyya, N. Bundaleski, A. Moutinho, O. Teodoro, L. Aguilera, M. Taborelli, and R. Schwarz. "{Secondary electron emission yield (SEY) in amorphous and graphitic carbon films prepared by PLD}." Physica Status Solidi C. 3 (2012): 1-3. Abstract

High secondary emission yield (SEY), and the subse- quent build-up of a secondary electron cloud, may se- verely limit the stability of high-intensity particle beams inside particle accelerators. One of the best candidates of beam pipe coating for reduced SEY has been amorphous carbon (a-C) produced by direct current (D.C.) magne- tron sputtering. Here we used pulsed laser deposition (PLD), to prepare a-C films from a pure carbon target at substrate temperatures ranging from 300 K to 773 K. The ablating laser was a Nd:YAG system operating at 1064 nm wavelength. With increasing temperature the optical band gap dropped from about 2.1 eV to 1.0 eV. This trend indicates transition from predominantly a-C films to films with more graphitic content, which was also con- firmed by Raman measurements. SEY spectra were taken upto 1732 eV of primary electron energy. The maximum SEY value decreased from 1.9 in a-C films down to 1.4 in highly graphitic films deposited at higher temperatures

Ghumman, C. A. A., A. M. C. Moutinho, A. Santos, A. Tolstogouzov, and O. M. N. D. Teodoro. "{TOF-SIMS study of cystine and cholesterol stones}." Journal of Mass Spectrometry. 47 (2012): 547-551. Abstract

Two different human stones, cystine and cholesterol from the kidney and gall bladder, were examined by time-of-flight sec- ondary ion mass spectrometry using Ga+ primary ions as bombarding particles. The mass spectra of kidney stone were com- pared with those measured for the standard compounds, cystine and cysteine. Similar spectra were obtained for the stone and cystine. The most important identification was based on the existence of the protonated molecules [M+H]+ and deprotonated molecules [M-H]-. The presence of cystine salt was also revealed in the stone through the sodiated cystine [M+Na]+ and the associated fragments, which might be due to the patient treatment history. In the gallstone, the deprotonated molecules [M-H]+ of cholesterol along with relatively intense characteristic fragments [M-OH]+ were detected. Copyright © 2012 John Wiley & Sons, Ltd.

Ghumman, C. A. A., A. M. C. Moutinho, A. Santos, O. M. N. D. Teodoro, and A. Tolstogouzov. "{TOF-SIMS VG Ionex IX23LS : upgrade and application for the urinary stones analysis}." Applied Surface Science (2012). Abstract

TOF-SIMS VG Ionex IX23LS with upgraded data acquisition and control system was used to study the real urinary stones along with calcium oxalate (COX) and four different calcium phosphate (CP) references. Reliable phase identification of CPs was achieved in the positive SIMS mode on basis of the PO+/POH+ and CaPO2+/Ca2O+ peak ratios. In real urinary stones, pure COX was distinguished from calcium phosphates with confidence via the presence of its characteristic ion peaks. We also quantified the calcium phosphate in the human calculi containing calcium oxalate as major or minor component, which is of a great interest for medical community

2011
Ghumman, Amjad C. A., Augusto M. C. Moutinho, Alexander Tolstogouzov, and Orlando M. N. D. Teodoro. "{Time-of-flight secondary ion mass spectrometric identification of calcium formate Ca(HCO2)2 and metabolite of vitamin B6 in human stones}." Rapid communications in mass spectrometry : RCM. 25 (2011): 997-9. AbstractWebsite
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and Mesquita, Orlando Teodoro M. N. D. A. C. "Gás libertado de uma rolha após engarrafamento." Enovotis. julho/agosto/setembro 2011 (2011): 42-45.2011_enologia_gs_libertado.pdf