Rui Barbosa - Academia.edu (original) (raw)

Papers by Rui Barbosa

Renewable Energy and Power Quality Journal, 2011

Since the 90's decade there are severe restrictions to the use of MBM, due to BSE. The co-combust... more Since the 90's decade there are severe restrictions to the use of MBM, due to BSE. The co-combustion of Meat and Bone Meal (MBM) and coal is a possible energetic valorization route for MBM. However, the chemical and ecotoxicological properties of the ashes produced in this co-combustion process need to be more characterized. In order to evaluate the chemical and ecotoxicological properties of this type of ashes, three combustion tests were performed in a fluidized bed reactor (FBR): 1) combustion of coal; 2) co-combustion of coal and MBM; 3) combustion of MBM. The characterization of the ashes was focused on the following aspects: (1) the bulk content of metals; and (2) the chemical and ecotoxicological characterization of eluates. The ashes were classified according to their ecotoxicity levels based on the French regulation CEMWE. According to Council Decision (CD) 2003/33/EC, all fly ashes need stabilization prior to landfilling, except the 1 st cyclone ash produced in the co-combustion test that could be landfilled in a hazardous waste landfill. The bottom ashes were classified as non-hazardous residues. The novelty of this paper is related with two aspects: 1) the use of MBM as co-fuel; and 2) both chemical and ecotoxicological characterization of the ashes produced during the combustion of coal and MBM.

Journal of Colloid and Interface Science, 2014

The main aim of this work was to study the removal efficiency of Pb from synthetic and industrial... more The main aim of this work was to study the removal efficiency of Pb from synthetic and industrial wastewaters by using biomass fly ashes. The biomass fly ashes were produced in a biomass boiler of a pulp and paper industry. Three concentrations of Pb 2+ were tested in the synthetic wastewater (1, 10 and 1000 mg Pb/L). Moreover, two different wastewaters were collected in an industrial wastewater treatment plant (IWWTP) of an industry of lead-acid batteries: (i) wastewater of the equalization tank, and (ii) IWWTP effluent. All the wastewaters were submitted to coagulation-flocculation tests with a wide range of biomass fly ashes dosage (expressed as Solid/Liquid -S/L -ratios). All supernatants were characterized for chemical and ecotoxicological parameters. The use of biomass fly ashes has reduced significantly the Pb concentration in the synthetic wastewater and in the wastewaters collected in the IWWTP. For example, the definitive coagulation-flocculation assays performed over the IWWTP effluent presented a very low concentration of Pb (0.35 mg/L) for the S/L ratio of 1.23 g/L. Globally, the ecotoxicological characterization of the supernatants resulting from the coagulation-flocculation assays of all wastewaters has indicated an overall reduction on the ecotoxicity of the crude wastewaters, due to the removal of Pb.

Char residues produced in co-pyrolysis of different wastes were characterized through chemical an... more Char residues produced in co-pyrolysis of different wastes were characterized through chemical and toxicity tests. A fraction of the solid chars was treated by extraction with dichloromethane. Different volatilit fractions present in the extracted and non extrated char ...

Communications in Mathematical Physics, 2019

Observable properties of a classical physical system can be modelled deterministically as functio... more Observable properties of a classical physical system can be modelled deterministically as functions from the space of pure states to outcome values; dually, states can be modelled as functions from the algebra of observables to outcome values. The probabilistic predictions of quantum physics are contextual in that they preclude this classical assumption of reality: noncommuting observables, which are not assumed to be jointly measurable, cannot be consistently ascribed deterministic values even if one enriches the description of a quantum state. Here, we consider the geometrically dual objects of noncommutative operator algebras of observables as being generalisations of classical (deterministic) state spaces to the quantum setting and argue that these generalised state spaces represent the objects of study of noncommutative operator geometry. By adapting the spectral presheaf of Hamilton-Isham-Butterfield, a formulation of quantum state space that collates contextual data, we reconstruct tools of noncommutative geometry in an explicitly geometric fashion. In this way, we bridge the foundations of quantum mechanics with the foundations of noncommutative geometry à la Connes et al. To each unital C * -algebra A we associate a geometric object-a diagram of topological spaces collating quotient spaces of the noncommutative space underlying A-that performs the role of a generalised Gel'fand spectrum. We show how any functor F from compact Hausdorff spaces to a suitable target category C can be applied directly to these geometric objects to automatically yield an extension F acting on all unital C * -algebras. This procedure is used to give a novel formulation of the operator K 0 -functor via a finitary variant K f of the extension K of the topological K -functor. We then delineate a C * -algebraic conjecture that the extension of the functor that assigns to a topological space its lattice of open sets assigns to a unital C * -algebra the Zariski topological lattice of its primitive ideal spectrum, i.e. its lattice of closed two-sided ideals. We prove the von Neumann algebraic analogue of this conjecture.

Materials Science Forum, 2006

This paper is mainly focused on the characterisation of a glass material (GM) obtained from the t... more This paper is mainly focused on the characterisation of a glass material (GM) obtained from the thermal treatment of a bottom ash (BA) produced at the Municipal Solid Waste (MSW) incineration plant of Valorsul. By melting the BA at 1400°C during 2 hours, and without using any chemical additives, a homogeneous black-coloured glass was obtained. The thermal and mechanical properties of this glass were characterised. The thermal expansion coefficient, measured by dilatometry, was 9-10 x 10-6 per °C and the modulus of rupture, determined by four-point bending test, was 75±6 MPa, which are similar values to those exhibited by commercial soda-lime-silica glasses used in structural applications. The chemical and the ecotoxicological leaching behaviour of the GM were also analysed. The GM was submitted to a leaching procedure composed of 15 sequential extraction cycles. A liquid/solid (L/S) ratio of 2 l/kg was applied in each cycle. The leachates were filtered through a membrane of PTFE (po...

Advanced Materials Research, 2012

The main aim of this work was to assess the possibility of using biomass ashes as substitutes for... more The main aim of this work was to assess the possibility of using biomass ashes as substitutes for cement and natural aggregates in concretes without compromising their mechanical and chemical properties. Thirteen concrete formulations were prepared with different percentages of bottom and fly ashes produced at a forest biomass power plant. These formulations were submitted to mechanical compressive strength assays, after 28, 60 and 90 days of maturation. The reference formulation F1 that was produced without biomass ashes and one formulation incorporating fly and bottom ashes, F4, were selected for further characterization. After 90 days of maturation, the selected formulations were submitted to the leaching test described in the European Standard EN12457-2 (L/S ratio of 10 L/kg, in a batch extraction cycle of 24h) by using two different leaching agents: a synthetic marine medium (ASPM medium) and a synthetic freshwater medium (ISO 6341 medium). The eluates produced were submitted to chemical characterization which comprised a set of metals (As, Sb, Se, Cu, Zn, Ba, Hg, Cd, Mo, Pb, Ni, Cr, Cr VI, Al, Fe, Mg, Na, K and Ca), pH, SO42-, F-, dissolved organic carbon, chlorides, phenolic compounds and total dissolved solids. The substitution of 10% cement by fly ashes has not promoted the reduction of the compressive strength of concrete. The new formulation F4 has presented emission levels of chemical species similar or even lower to those observed for the reference formulation F1.

Waste Management, 2010

The high amounts of solid waste produced in industrial installations and in urban centers is a co... more The high amounts of solid waste produced in industrial installations and in urban centers is a complex problem of today's society. The traditional strategies for solid waste transformation and disposal include landfilling or incineration. Other approaches are being exploited namely waste selective collection and recycling or the energetic valorization of solid wastes through pyrolysis. Regarding the release of heavy metals from extracted and non-extracted chars during the leaching tests, a strong contamination with Zn was found in both eluates, which contribute to a classification of the corresponding chars as hazardous and ecotoxic materials. Also the results of the ecotoxicological characterization of the eluates led to a classification of these chars as ecotoxic materials.

Journal of Hazardous Materials, 2009

The co-combustion of sewage sludge (SS) and coal is widely used for the treatment and thermal val... more The co-combustion of sewage sludge (SS) and coal is widely used for the treatment and thermal valorization of SS produced in wastewater treatment plants. The chemical and ecotoxicological properties of the ashes produced in this thermal treatment have not been fully studied. Two combustion tests were performed in a fluidized bed combustor. Colombian coal was used as fuel in test A. A blend (1+1) of this coal and a stabilized SS (Biogran) was used in a second test B. Samples of the bottom and fly ashes trapped in two sequential cyclones were collected. The characterization of the ashes was focused on two main aspects: (1) the bulk content of a set of metals and (2) the characterization of eluates produced according to the European Standard leaching test EN 12457-2. The eluates were submitted to an ecotoxicological characterization for two bio-indicators. In what concerns the bulk content of ashes, both combustion tests have produced ashes with different compositions. The ashes formed during the co-combustion test have shown higher concentrations of metals, namely Cr, Cu, Ni, Pb, Zn and Fe for all ashes. The leaching test has shown low mobility of these elements from the by-products produced during the combustion and co-combustion tests. Cr and Cr(VI) were mainly detected in the eluates of the 1st cyclone ashes produced in both combustion tests and in the 2nd cyclone ashes produced in the co-combustion test. Considering the ecotoxicity assays, the eluates of bottom and fly ashes for both combustion and co-combustion tests have shown low ecotoxic levels. The micro-crustacean Daphnia magna was generally more sensitive than the bacterium Vibrio fischeri. CEMWE criterion has allowed to classify the bottom ashes for both combustion and co-combustion tests as non-toxic residues and the fly ashes collected in both cyclones as toxic.

Journal of Hazardous Materials, 2012

Fuel Processing Technology, 2012

The replacement of fossil fuels by renewable fuels can contribute to improve the environmental pe... more The replacement of fossil fuels by renewable fuels can contribute to improve the environmental performance of the power production and to move forward in the sustainability way. The experience has shown that the availability of alternative fuels can be an obstacle for its extensive use for energy production, since biomass is not always available. The use of non-hazardous wastes may be a good alternative to biomass, mainly if they are economically unattractive for recycling or if they present a high cost for land-filling. The co-firing of non-hazardous wastes with coal is, therefore, a subject of great interest for the sustainability of energy production and the reduction of the emissions of fossil greenhouse gases. The use of these wastes for energy is promising if they combine well with other fuels during the conversion process for energy production and have no negative effect on the combustion system, on the ash quality and on the gaseous emissions. The DEECA/INETI team has performed three combustion assays in a pilot fluidizedbed combustor: a) combustion of coal; b) co-combustion of coal (85%) and meat and bone meal (MBM) (15%); c) combustion of MBM. Each combustion test has produced three types of ashes: 1) bottom ashes; 2) fly ashes collected in the first cyclone; 3) fly ashes collected in the second cyclone. The UBiA/FCT/UNL team has analyzed of the bulk content of the fuels and of the ashes. The quantification of the bulk content was performed according with the USEPA Method 3051A. The ashes were also characterized for chemical and ecotoxicological parameters. The ashes were submitted to the leaching test defined in the European Standard EN 12457-2. The eluates were also characterized for chemical and ecotoxicological characterization. The chemical characterization of the eluates included the following parameters: pH, dissolved organic carbon (DOC), cyanides, chlorides, sulfates, phenolic compounds, total dissolved solids

Construction and Building Materials, 2013

h i g h l i g h t s Concrete formulations using biomass ashes were prepared. Concrete with 10% of... more h i g h l i g h t s Concrete formulations using biomass ashes were prepared. Concrete with 10% of fly ashes: similar/slightly higher compressive strength values. Similar emission levels of chemical species in marine/freshwater leaching conditions. Similar ecotoxicological levels under marine/freshwater leaching conditions.

Archaeological and Anthropological Sciences, 2021

Phoenician-Punic glass beads recovered from the necropolis of Vinha das Caliças 4 (Beja, Portugal... more Phoenician-Punic glass beads recovered from the necropolis of Vinha das Caliças 4 (Beja, Portugal), dated to the Iron Age, were studied by variable pressure scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (VP-SEM–EDS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). All glass was found to be soda-lime-silica natron-based glass. Trace element and rare earth element analysis suggest that the blue, turquoise, white, and colorless glass was manufactured in the Levant region, using rather pure coastal sands, while two amber and black-colored glass beads seem to have been produced in Egypt. Although the exact manufacture location of these Phoenician-Punic glass beads remains unknown, these results are in agreement with the commercialization of raw glass produced in established primary glass workshops in the Levant and in Egypt. The procurement of cobalt ores from specific geological provinces, on the other hand, is a strong evidence of the existence of large-scale trade routes of both raw materials and finished artefacts in the Iron Age. The finished artefacts trade routes included not only the previously established Mediterranean world and sub-Saharan Africa, but also Southern Central Iberia.

Techniques in Hand & Upper Extremity Surgery, 2009

Coverage of a soft tissue defect of the thumb that cannot be replanted or without bone shortening... more Coverage of a soft tissue defect of the thumb that cannot be replanted or without bone shortening is difficult to achieve, but it is essential to preserve key-pinch and to restore a sensible and painless pulp. We reviewed retrospectively 107 cases of thumb reconstruction in an emergency situation using the following flaps: Moberg, radial innervated cross-finger, Venkataswami-Subramanian, Foucher, Tezcan, and Littler. The choice of the flap was determined by the extension and location of the injury; Foucher flap (56 cases) was the most used one, and it proved to be the best choice as shown by the results. Nevertheless, Tezcan flap also proved to be a good alternative.

European Journal of Plastic Surgery, 2011

Microsurgery, 2009

Background: Complete traumatic upper extremity avulsions are an infrequent but devastating injury... more Background: Complete traumatic upper extremity avulsions are an infrequent but devastating injury. These injuries are usually the result of massive blunt trauma to the upper limb. Intact issue from amputated or nonsalvageable limbs may be transferred for reconstruction of complex defects resulting from trauma when the indications for replantation are not met. This strategy allows preservation of stump length or coverage of exposed joints, and provides free flap harvest for reconstruction without additional donor-site morbidity. Methods: A retrospective review at Sã o Joã o Hospital was performed on seven patients who had undergone immediate reconstruction with forearm free fillet flaps between 1992 and 2007. Results: There were six men and one woman, with patient age ranging from 17 to 74 years (mean, 41 years). Amputation sites were at the humeral neck (n 5 1), at the humeral shaft (n 5 5), and below the elbow (n 5 1). The area of the forearm free fillet flap skin paddle was 352.14 6 145.48 cm (mean 6 SD). The two major complications were the flap loss and the patient death on postoperative day 3 in other case. The postoperative course in the remaining five cases was uneventful with good healing of the wounds. Minor complications included two small residual defects treated by split-thickness skin grafting and one wound infection requiring drainage and revision. Conclusions: The forearm free fillet flap harvested from the amputated limb provides reliable and robust tissue for reconstruction of large defects of the residual limb without additional donor-site morbidity. Microsurgical free fillet flap transfer to amputation sites is valuable for achieving wound closure, improving stump durability, and maximizing function via preservation of length.