728 research outputs found
Predation On Native Anurans By Invasive Vertebrates In The Atlantic Rain Forest, Brazil
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)203 Specia lissue7074161812/2011-2, CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico303776/ 2015-3, CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico3855/13-9, CAPES, Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Asymptotics of 4d spin foam models
We study the asymptotic properties of four-simplex amplitudes for various
four-dimensional spin foam models. We investigate the semi-classical limit of
the Ooguri, Euclidean and Lorentzian EPRL models using coherent states for the
boundary data. For some classes of geometrical boundary data, the asymptotic
formulae are given, in all three cases, by simple functions of the Regge action
for the four-simplex geometry.Comment: 10 pages, Proceedings for the 2nd Corfu summer school and workshop on
quantum gravity and quantum geometry, talk given by Winston J. Fairbair
On-line Microwave Slurry Sample Digestion Using Flow Systems For The Spectrophotometric Determination Of Iron In Seafood
A method for the spectrophotometric determination of iron in seafood slurry samples based on microwave assisted digestion has been developed. The stabilized slurry (200 μl) is introduced in a flow system and transported by an air carrier stream to a digestion coil positioned inside the microwave oven. After the digestion step (10 or 20 min at maximum power) the flushing solution is collected in a calibrated flask. A 200 μl-digested sample is introduced in a flow injection system and the iron determined at 512 nm with 1,10-phenanthroline. The proposed method features a linear range from 50 to 200 μg l-1 (r > 0.999) presenting a precision, expressed as RSD, of 3.7% (n = 10) for repeatability and 5.0% (n = 30) for reproducibility. Accuracy was assessed by using Standard and Certified Reference Materials.123510231028Kingston, H.M., Jassie, L.B., (1988) Introduction to Microwave Sample Preparation - Theory and Practice, p. 263. , American Chemical Society, Washington, DCValcárcel, M., Luque De Castro, M.D., Tena, M.Y., (1993) Extracción con Fluidos Supercríticos en el Processo Analítico, p. 469. , Editorial Reverté S. A., BarcelonaBurguera, M., Burguera, J.L., (1996) Quím. Anal., 15, p. 112De La Guardia, M., Salvador, A., Burguera, J.L., Burguera, M.J., (1988) Flow Injection Anal., 5, p. 121Arruda, M.A.Z., Santelli, R.E., (1997) Quím. Nova, 20, p. 638De La Guardia, M., Carbonell, V., Morales-Rubio, A., Salvador, A., (1993) Talanta, 40, p. 1609Burguera, J.L., Burguera, M., Brunetto, M.R., (1993) At. Spectrosc., 14, p. 90Burguera, M., Burguera, J.L., Alarcón, O.M., (1996) Anal. Chim. Acta, 179, p. 351Burguera, M., Burguera, J.L., Alarcón, O.M., (1988) Anal. Chim. Acta, 214, p. 421Bryce, D.W., Izquierdo, A., Luque De Castro, M.D., (1996) Anal. Chim. Acta, 324, p. 69Guo, T., Baasner, J., (1993) Talanta, 40, p. 1927Hanna, C.P., McIntosh, S.A., (1995) At. Spectrosc., 16, p. 106Morales-Rubio, A., Mena, M.L., McLeod, C.W., (1995) Anal. Chim. Acta, 308, p. 364Cabrera, C., Madrid, Y., Cámara, C., (1994) J. Anal. At. Spectrom., 9, p. 1423López-Gonzálvez, M.A., Gómez, M.M., Cámara, C., Palacios, M.A., (1994) J. Anal. At. Spectrom., 9, p. 291Gluodenis Jr., T.J., Tyson, J.F., (1993) J. Anal. At. Spectrom., 8, p. 697Burguera, M., Burguera, J.L., Rondón, C., Rivas, C., Carrero, P., Gallignani, M., Brunetto, M.R., (1995) J. Anal. At. Spectrom., 10, p. 343Burguera, J.L., Burguera, M., (1993) J. Anal. At. Spectrom., 8, p. 235Arruda, M.A.Z., Gallego, M., Valcárcel, M., (1996) J. Anal. At. Spectrom., 11, p. 169Sooksamiti, P., Geckeis, H., Grudpan, K., (1996) Analyst, 121, p. 1413Cuesta, A., Todoli, J.L., Canals, A., (1996) Spectrochim. Acta, Part B, 51, p. 1791Bordera, L., Hernandis, V., Canal, A., Chem, F.A., (1996), 355, p. 112Lafuente, J.M.G., Sánchez, M.L.F., Marchante-Gayón, J.M., Uria, J.E.S., Sanz-Medel, A., (1996) Spectrochim.. Acta Part B, 51, p. 1849Chakraborty, R., Das, A.K., Cervera, M.L., De La Guardia, M., (1997) Anal. Lett., 30 (2), p. 283De Almeida, M.D., Leandro, K.C., Da Costa, C.V., Santelli, R.E., De La Guardia, M., (1997) J. Anal. At. Spectrom., 12, p. 1235Maksimova, I.M., Morosanova, E.I., Kuz'min, N.M., Zolotov, Y.A., (1997) Fresenius' J. Anal. Chem., 357, p. 946Carlosena, A., Gallego, M., Valcárcel, M., (1997) J. Anal. At. Spectrom., 12, p. 479Balconi, M.L., Borgarello, M., Ferracioli, R., Realini, F., (1992) Anal. Chim. Acta, 261, p. 295Schmitt, A., Buttle, L., Uglow, R., Williams, K., Haswell, S., (1993) Anal. Chim. Acta, 284, p. 249Benson, R.L., McKelvie, I.D., Hart, B.T., Hamilton, I.C., (1994) Anal. Chim. Acta, 291, p. 249Williams, K.E., Haswell, S.J., Barclay, D.A., Preston, G., (1993) Analyst, 118, p. 245Bergamin, H.Fo., Reis, B.F., Jacintho, A.O., Zagatto, E.A.G., (1980) Anal. Chim. Acta, 117, p. 81Mortatti, J., Krug, F.J., Pessenda, L.C.R., Zagatto, E.A.G., Jørgensen, S.S., (1982) Analyst, 107, p. 659Arruda, M.A.Z., Fostier, A.H., Krug, F.J., (1997) J. Braz. Chem. Soc., 8, p. 39Fostier, A.H., Ferreira, J.R., (1995) Quím. Nova, 18, p. 425Miller-Ihli, N.J., (1988) J. Anal. At. Spectrom., 3, p. 73Bendicho, C., De Loos-Vollebregt, M.T.C., (1991) J. Anal. At. Spectrom., 6, p. 353Januzzi, G.S.B., Krug, F.J., Arruda, M.A.Z., (1997) J. Anal. At. Spectrom., 12, p. 375(1987) Analyst, 112, p. 19
Semi-automatic rubble counting system for superheated droplet detectors
Neutron dose rate measurements are normally performed by means of PADC, CR-39 and TLD detectors.
Although, none of these devices can give instant reading of the neutron dose, recently new kind of detectors are
being developed, based on the formation of tiny drops in a superheated liquid suspended in a polymer or gel
solution, called superheated droplet detector (SDD) or also as bubble detectors (BD), with no response for
gamma radiation. This work describes the experimental setup and the developed procedures for acquiring and
processing digital images obtained with bubble detector spectrometer (BDS), developed by Bubble Technology
Industries, for personal neutron dosimeter and/or neutron energy fluence measurements in nuclear facilities. The
results of the neutron measurements obtained during the F-18 production, at the RDS-111 cyclotron, are
presented. These neutron measurements were the first ones with this type of BDS detectors in a particle
accelerator facility in Brazil and it was very important to estimate neutron dose rate received by occupationally
exposed individuals
One step forward towards the development of eco-friendly antifouling coatings: Immobilization of a sulfated marine-inspired compound
Marine biofouling represents a global economic and ecological challenge and few eco-friendly antifouling agents are available. The aim of this work was to establish the proof of concept that a recently synthesized nature-inspired compound (gallic acid persulfate, GAP) can act as an eco-friendly and effective antifoulant when immobilized in coatings through a non-release strategy, promoting a long-lasting antifouling effect. The synthesis of GAP was optimized to provide quantitative yields. GAP water solubility was assessed, showing values higher than 1000 mg/mL. GAP was found to be stable in sterilized natural seawater with a half-life (DT50) of 7 months. GAP was immobilized into several commercial coatings, exhibiting high compatibility with different polymeric matrices. Leaching assays of polydimethylsiloxane and polyurethane-based marine coatings containing GAP confirmed that the chemical immobilization of GAP was successful, since releases up to fivefold lower than the conventional releasing systems of polyurethane-based marine coatings were observed. Furthermore, coatings containing immobilized GAP exhibited the most auspicious anti-settlement effect against Mytilus galloprovincialis larvae for the maximum exposure period (40 h) in laboratory trials. Overall, GAP promises to be an agent capable of improving the antifouling activity of several commercial marine coatings with desirable environmental properties.This research was funded by national funds through the Foundation for Science and Technology (FCT) within the scope of research unit grants to CIIMAR (UIDB/04423/2020 and UIDP/04423/2020), to BioISI (UIDB/04046/2020 and UIDP/04046/2020) and under the project PTDC/AAG-TEC/0739/2014 (reference POCI-01-0145-FEDER-016793) supported through national funds provided by FCT and the European Regional Development Fund (ERDF) via the Programa Operacional Factores de Competitividade (POFC/COMPETE) programme and the Reforçar a Investigação, o Desenvolvimento Tecnológico e a Inovação (RIDTI; project 9471)
Genetic variability of Mycoplasma synoviae detected in commercial layers in southeastern Brazil
Mycoplasma gallisepticum como fator de risco no peso de lotes de frangos de corte com condenação por aerossaculite na Inspeção Sanitária Federal
Isothermal Deep Ocean Compressed Air Energy Storage: An Affordable Solution for Seasonal Energy Storage
There is a significant energy transition in progress globally. This is mainly driven by the insertion of variable sources of energy, such as wind and solar power. To guarantee that the supply of energy meets its demand, energy storage technologies will play an important role in integrating these intermittent energy sources. Daily energy storage can be provided by batteries. However, there is still no technology that can provide weekly, monthly and seasonal energy storage services where pumped hydro storage is not a viable solution. Herein, we introduce an innovative energy storage proposal based on isothermal air compression/decompression and storage of the compressed air in the deep sea. Isothermal deep ocean compressed air energy storage (IDO-CAES) is estimated to cost from 1500 to 3000 USD/kW for installed capacity and 1 to 10 USD/kWh for energy storage. IDO-CAES should complement batteries, providing weekly, monthly and seasonal energy storage cycles in future sustainable energy grids, particularly in coastal areas, islands and offshore and floating wind power plants, as well as deep-sea mining activities
UTILIZAÇÃO DE RESÍDUOS AGROINDUSTRIAIS AMONIZADOS COM BOVINOS EM REGIME DE SEMI-CONFINAMENTO
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