Authors:A. Ferreira, M. Saiki, J. Santos, A. Ribeiro and P. Saldiva
In this study, Canoparmelia texana lichenized fungi species was used as a passive biomonitor of the atmospheric pollution from the industrial city of São Mateus
do Sul, PR, Brazil. Lichen samples collected from tree barks were cleaned, freeze-dried and analyzed by neutron activation
analysis. Comparisons were made between the element concentrations obtained in lichens from this city and that from a clean
area of Atlantic Forest in Intervales Park, SP. The high concentrations of elements As, Ca, Co, Cr, Fe, Hf, Sb, and Th found
in lichens could be attributed to the emissions from a ceramic and an oil shale plants.
Authors:J. Rodrigues Silva, A. de Melo Ferreira and A. da Costa
The biosorption of uranium by the seaweed Sargassum filipendula was investigated under dynamic conditions at various bed heights. Our results indicate that a bed height of 40.0 cm (111.9
g biomass) was the most efficient for long-term operation of the continuous system. Our results also indicate that the effluent
solutions produced are in accordance with Brazilian legislation for safe discharge of uranium in aqueous streams. The efficiency
of the process increased with an increase in bed height from 5.0 to 40.0 cm due to changes in the transfer zone. In treatment
of a real effluent contaminated with uranium, stable heavy metals and essential metals, 64% of the uranium was biosorbed,
as well as the stable heavy metals chromium, lead and barium. The essential metals calcium, magnesium, iron and manganese
were not biosorbed by the seaweed, in fact, their concentrations in the solution increased due to ion-exchange mechanisms
with the constituent polysaccharides of the biomass. Another important result was the 85–87% reduction of mass obtained after
drying and calcination of the biomass. This is a relevant indication that long-term storage of biomass loaded with radionuclides
and heavy metals is possible after concentration of the contaminants. In the present work, the reduction in total mass of
the loaded biomass was considerable, thus facilitating storage of the contaminated seaweed.
Authors:M. H. Braga, J. A. Ferreira and M. J. Wolverton
Finite fossil-fuel supplies, nuclear waste and global warming linked to CO2 emissions have made the development of alternative/‘green’ methods of energy production, conversion and storage popular topics in today’s energy-conscious society. These crucial environmental issues, together with the rapid advance and eagerness from the electric automotive industry have combined to make the development of radically improved energy storage systems a worldwide imperative. CuMg2 has an orthorhombic crystal structure and does not form a hydride: it reacts reversibly with hydrogen to produce Cu2Mg and MgH2. However, CuLixMg2−x (x = 0.08) has a hexagonal crystal structure, just like NiMg2, a compound known for its hydrogen storage properties. NiMg2 absorbs up to 3.6 wt% of H. Our studies showed that not only CuLixMg2−x absorbs a considerable amount of hydrogen, but also starts releasing it at a temperature in the range of 40–130 °C. In order to determine the properties of the hydrogenated CuLixMg2−x, absorption–desorption, Differential scanning calorimeter and thermo-gravimetric experiments were performed. Neutron spectra were collected to elucidate the behavior of hydrogen in the Li-doped CuMg2 intermetallic. Using DFT calculations we were able to determine the best value for x in CuLixMg2−x and compare different possible structures for the CuLixMg2−x hydride.
Authors:M. Ginja, Maria Llorens-Pena, J. Gonzalo-Orden and A. Ferreira
A modified PennHIP procedure (MPP), using specific mechanical holding devices, was used on 70 dogs and compared to the standard PennHIP method (SPM) used on 39 dogs, in terms of technical effectiveness and the mean number of essential individuals within the X-ray room (EIXRR). The data using the Chisquared test were consistent with the null hypothesis that the technical effectiveness was equal in the groups under investigation (P > 0.05). On the contrary, using the two-sample unpaired
-test the null hypothesis, that the mean EIXRR was equal, was rejected (P < 0.001). The estimated EIXRR was 3.4 ± 0.7 and 5.7 ± 1.2 (mean ± SD) for MPP and SPM, respectively. In conclusion, the MPP needs fewer EIXXR than the SPM and complies with the new recommendations in X-ray protection, which introduce the ALARA (as-low-as-reasonably-achievable) idea.
Authors:M. Ferreira, S. Pereira, A. Almeida, R. Queirós, I. Delgadillo, J. Saraiva and A. Cunha
The main objective of the present study was to evaluate the effect of temperature and different compression/ decompression rates on the efficiency of Listeria inactivation by HPP.
Stationary phase cultures of Listeria innocua were subjected to 300 MPa for 5 min at 4, 10, and 20 °C using different compression and decompression rates. Inactivation was more efficient at low temperature and with lowest compression and decompression rates (1.5 MPa s–1 and 3.2 MPa s–1, respectively).
Kinetics of pressure building up and decompression, as well as temperature, have a significant impact on the outcome of Listeria inactivation by HPP. The results may contribute to the design of HPP protocols that ensure food safety, while preserving nutritional and organoleptic properties better.
Authors:R. Rodríguez Madrera, B. Suárez Valles, A. Campa Negrillo and J.J. Ferreira Fernández
Blueberry (Vaccinium spp.) cultivation has experienced a notable increase both for its good organoleptic characteristics and the nutritional and functional properties of this berry. The aim of this study was the physicochemical characterization of blueberry juices obtained from 55 blueberry cultivars grown under the same environmental conditions for 2–4 years. The results provide a broad and robust database, both for the number of cultivars and the periods of monitoring thereof, in order to cover different aspects of blueberry processing, and more specifically, production of juices. Blueberries belonging to V. virgatum cultivars showed the higher values of total anthocyanin content, total phenolic content, antioxidant activity, soluble solids, and pH, and V. corymbosum cultivars the higher level of titratable acidity. Results also showed a high variability among cultivars. Observed variations can be used in plant breeding and classification of blueberry cultivars, at least, at the species level.
Authors:M. M. D. Ginja, A. J. A. Ferreira, M. Silvestre, J. M. Gonzalo-Orden and M. P. Llorens-Pena
Repeatability and reproducibility of Distraction Index (DI) measurements in the PennHIP method were evaluated in 100 dogs. The PennHIP distraction views sent to the PennHIP Analysis Center (PAC) were duplicated, digitalised, and identified with a code, and an adequate computer software was used for DI measurements. One examiner performed two DI measurement sessions, evaluating individually 200 hip joints. The scoring repeatability and reproducibility were estimated calculating the Intraclass Correlation Coefficient (ICC) between the two DI measurement sessions and between the second DI measurement session and the DI in PAC reports, respectively. The ICC for repeatability was 0.97 [95% confidence interval (CI), 0.96 to 0.98], and the ICC for reproducibility was 0.95 (95% CI, 0.93 to 0.96). The results suggest that the DI measurement method described is repeatable and can reproduce the PAC reports with confidence. Distraction indices measured in different PennHIP studies, using this DI measurement method and performed by trained researchers, can be considered interchangeable.
Authors:A. de Oliveira, J. Ferreira, Márcia Silva, Soraia de Souza, F. Vieira, E. Longo, A. Souza and Iêda Santos
NiWO4 and ZnWO4 were synthesized by the polymeric precursor method at low temperatures with zinc or nickel carbonate as secondary phase.
The materials were characterized by thermal analysis (TG/DTA), infrared spectroscopy, UV–Vis spectroscopy and X-ray diffraction.
NiWO4 was crystalline after calcination at 350 °C/12 h while ZnWO4 only crystallized after calcination at 400 °C for 2 h. Thermal decomposition of the powder precursor of NiWO4 heat treated for 12 h had one exothermic transition, while the precursor heat treated for 24 h had one more step between
600 and 800 °C with a small mass gain. Powder precursor of ZnWO4 presented three exothermic transitions, with peak temperatures and mass losses higher than NiWO4 has indicating that nickel made carbon elimination easier.
Authors:J. R Ferreira, E. A. N. Fernandes, E. J. França, G. A. Tavares, N. C. da Silva and M. H. T. Taddei
Sediment cores from Catingueiro, Barrinha and Rio das Pedras marginal lagoons of the Moji-Guaçu River basin were analyzed
for rare earth elements (REEs), Fe, Ta and Th by instrumental neutron activation analysis (k0-INAA). Data indicated similarities between Catingueiro and Barrinha lagoons, while a distinct scenario was seen for Rio das
Pedras likely due to changes of sedimentation rate in 1950's. By using Fe, Sc, Ta and Th as conservative elements, double
normalization technique was performed in order to assess the distribution pattern of Ce, Eu, La, Sm and Tb for each core.
In all cases, it was evident a depletion of lighter REE elements in the Rio das Pedras lagoon.
Authors:J. J. H. Lancastre, F. M. A. Margaça, L. M. Ferreira, A. N. Falcão, I. M. Miranda Salvado, M. S. M. S. Nabiça, M. H. V. Fernandes and L. Almásy
Silicate hybrid materials were prepared by the sol–gel process with the addition of x mass% of zirconium propoxide (x = 0 and 1). The thermal behaviour as well as the influence of Zr addition was studied by thermal gravimetric analysis and differential thermal analysis. The microstructure evolution with temperature was investigated by X-ray diffraction and small-angle neutron scattering. It was found that the beginning of polymer degradation occurs at a higher temperature in the material prepared with addition of Zr than in the one prepared without. At the nanometric scale, the materials prepared without Zr show smooth interfaces, whereas those with Zr present a mass fractal structure. This structure is also observed in the material without Zr after thermal treatment at 200 °C. The results showed that bioactivity is favoured by mass fractal structures in comparison with one consisting of smooth surfaces.