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Analysis of Radium Isotopes in surface Waters nearby a Phosphate Mining with NORM at santa Quiteria,Brazil

Journal of Environmental Protection 2014年第3期5卷 193-199页

作者： wagner de s.pereira Alphonse Kelecom Juliana R.de s.pereira Multidisciplinary Group of Radioprotection(GMR) Servico de RadioprotecaoUnidade de Tratamento de MinerioIndustrias Nucleares do BrasilCaldasBrazil Laboratory of Radiobiology and Radiometry Pedro Lopes dos santos(LARARA-PLs) Group of Environmental Themes Assessment(GETA)Universidade Federal Fluminense(UFF)NiteroiBrazil Interdisciplinary Under-Graduation in science and Technology Universidade Federal de AlfenasPocos de CaldasBrazil

The radium isotopes 226Ra and 228Ra were analyzed in surface water at six points in the neighborhood of a mine of phosphate, associated with uranium, in the region of santa Quitéria, state of Ceará, Brazil. Water samples were collected during twenty months, filtered and the concentrations of activity determined in the soluble and particulate phases. The results were analyzed using the Principal Component Analysis (PCA) for ordination of environmental data, and also by ANOVA, Tukey and Z tests to compare sets of data considering the radionuclides, the two analyzed phases and the six collecting points. The PCA identified four groups that included all collecting points, using aggregation features such as radionuclide and analyzed phase. The first group is composed by the samples of 226Ra in the soluble phase;the second group by samples of 226Ra in the particulate phase;the third one by 228Ra in the soluble phase, and finally, the fourth group by 228Ra in the particulate phase. This last group has two discrepant points (01 and 06). statistical analysis identified differences between the concentrations of activity of radionuclides (228Ra higher than 226Ra) and in analyzed phases (soluble phase higher than the particulate one) but showed no differences between sampled points.

关键词： Radioecology Environmental Radioprotection NORM Mining Radium Isotopes PCA

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International Recommendations on Calculation of Absorbed Dose in Biota:A Comprehensive Revue

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Journal of Environmental Protection 2014年第9期5卷 751-759页

作者： wagner de s.pereira Alphonse Kelecom Multidisciplinary Group of Radio Protection(GMR) Servico de RadioprotecaoUnidade de Tratamento de MinerioIndustrias Nucleares do BrasilCaldasBrazil Laboratory of Radiobiology and Radiometry Pedro Lopes dos santos(LARARA-PLs) Group of Environmental Themes Assessment(GETA)Universidade Federal Fluminense(UFF)NiteroiBrazil

since the early times, radioprotection has been focused on the human being. Currently this approach has changed, being now also necessary to take care of the protection of the environment from unwanted effects of ionizing radiation. To this end, several institutions (UNsCEAR, ICRP, IAEA, DOE, ACRP) and consortia of institutions (FAssET, ERICA) have established procedures in order to protect the biota of such effects. developed procedures are based on the calculation of the absorbed dose in biota (ICRP, DOE, IAEA), or on environmental risk assessment―ERA (DOE, ACRP, FAssET, ERICA);but even in this latter approach the parameters used are related to the absorbed doses in biota. The calculation of dose is the standard procedure in human radioprotection, and this points such an approach as the most interesting for providing a convergence between human and nonhuman (= biota) radioprotections. On the other hand, the ERA approach is easier to apply, because this methodology is used in several countries for non-radioactive contamination assessments. since the world radioprotection system follows a number of institutions (UNsCEAR, ICRP, IAEA and regulatory institutions of member countries) that use dose calculation, this appears to be the way for biota radioprotection. We here review and comment the evolution of the concepts and approaches of the recommendations for radioprotection of non-human biota.

关键词： Biota Absorbed Dose Radioprotection International Recommendations

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Release of Uranium by an Ore Treatment Unit at Caldas,MG,Brazil

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Journal of Environmental Protection 2013年第6期4卷 570-574页

作者： wagner de s.pereira Alphonse Kelecom Juliana R.de s.pereira delcy de A.Py Junior Multidisciplinary Group of Radioprotection(GMR) Servico de RadioprotecaoUnidade de Tratamento de MinerioIndustrias Nu-cleares do BrasilCaldasBrazil Laboratory of Radiobiology and Radiometry Pedro Lopes dos santos(LARARA-PLs) Group of Environmental Themes Assessment(GETA)Universidade Federal Fluminense(UFF)NiteroiBrazil Interdisciplinary under Graduation in science and Technology Universidade Federal de AlfenasPocos de CaldasBrazil

This study aims to assess the behavior of the release of Unat (i.e. uranium isotopes in natural relative abundance) from the release of water treated by the Ore Treatment Unit (UTM) in Caldas, state of Minas Gerais, Brazil, during the years 1999 to 2009. During this period, the unit showed no industrial activity, except between 2004 and 2005, when UTM operated 400 tons of monazite in a process to obtain rare earths. Unat was analyzed by spectrophotometry once per week in the effluent waters at sampling point 014. Two fractions were considered for analysis: the soluble one (that passes through a 0.45 μm filter) and the particulate one (retained on a 0.45 μm filter). statistical analyses were performed: the “Z” test and Pearson’s r2 correlation index. The values for the soluble fraction were consistently lower than those of the particulate fraction and no statistically significant correlation was observed between the soluble and particulate fractions. However, the particulate and the total fractions (the sum of soluble and particulate) strongly correlated.

关键词： Uranium Ore Treatment Unit Caldas Radionuclide Monitoring

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Cooperative Localization and Tracking in Distributed Robot-sensor Networks

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Tsinghua science and Technology 2005年第1期10卷 91-101页

作者：张帆 Guilherme s.pereira Vijay Kumar General Robotics Automation sensing and Perception Laboratory University of Pennsylvania Philadelphia PA USA

This paper addresses the problem of real-time position and orientation estimation of networked mobile robots in two-dimensional Euclidean space with simultaneous tracking of a rigid unknown object based on exteroceptive sensory information extracted from distributed vision systems. The sufficient and necessary conditions for team localization are proposed. A localization and object tracking approach based on statistical operators and graph searching algorithms is presented for a team of robots localized with het- erogeneous sensors. The approach was implemented in an experimental platform consisting of car-like mobile robots equipped with omnidirectional video cameras and IEEE 802.11b wireless networking. The experimental results validate the approach.

关键词： cooperative localization multi-robot formation distributed sensor network sensor data fusion

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Tunable super-structured Fiber Bragg Gratings with Perfect sequences Based on m-sequence

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Journal of Electronic science and Technology 2017年第4期15卷 358-363页

作者： Joao s.pereira Marco P.M.Ferreira Marko Gasparovic Instituto de Telecomunicacoes Lisboa 1049-001 Portugal Institute Polytechnic of Leiria Leiria 2411-901 Portugal Centro de Investigaao em Informaica e Comunicacoes Institute Polytechnic of Leiria Leiria 2411-901Portugal

Recently, a tunable fiber Bragg grating(FBG) was developed by using stress-responsive colloidal crystals. In this paper, we have simulated the application of these nanoparticles into the super-structured fiber Bragg grating(ssFBG) written with perfect sequences derived from a short maximal-length sequence. A tunable ssFBG will be available to overcome the prohibitive temperature variation of the optical codecs. Nevertheless,we presented a method to implement coherent time spreading optical code-division multiple-access(OCDMA) where a unique code(or perfect sequence) can be reused and mixed with different wavelengths to obtain a tunable wavelength-division multiplexing(WDM)system. In order to maximize the binary throughput, we have selected a unique short maximal-length sequence composed of 7 chips that can be tuned with 7 different optical wavelengths. We found thousands of different tunable combinations that presented power contrast ratios(P/C) higher than 12 dB. When a WDM-OCDMA system used 2 different combinations simultaneously, the perfect binary detection with error correction codes was achieved successfully. The tunable ssFBG with colloidal crystals will be a simple and good alternative choice for fiber-to-the-home(FTTH) communications.

关键词： Optical code-division multiple-access(OCDMA) super-structured fiber Bragg grating(ssFBG) wavelength-division multiplexing OCDMA(WDM-OCDMA)

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Using hot-vapor bypass for pressure control in distillation columns

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Chinese Journal of Chemical Engineering 2018年第1期26卷 144-151页

作者： stefano Ciannella Arthur siqueira Damasceno Icaro Caze Nunes Gilvan Wanderley de Farias Neto wagner Brandao Ramos Romildo pereira Brito department of Chemical Engineering Federal University of Campina GrandeCarnpina Grande 58109-970ParafbaBrazil

Distillation column control is widely explored in literature due to its complexity and importance in chemical and petrochemical industries. In this process, pressure represents one of the most important variables to be controlled. However, there are few studies about how pressure affects the dynamic behavior of distillation columns and most research on distillation column control involve direct manipulation of cooling fluid through the condenser. Nevertheless, such an approach demands constant changes in cooling fluid flowrates that are commonly by the order of tons per hour, which can be difficult to work or even unfeasible in a real plant. Furthermore, this strategy is usually avoided, as it can cause fouling and corrosion acceleration. The hot-vapor bypass strategy fits well as a solution for these issues, eliminating the need to dynamically manipulate cooling fluid flowrates in the condensation unit. This work presents the modeling and simulation of a conventional distillation column for the separation of water and ethanol, in which a comparative study between a conventional pressure control and a control using hot-vapor bypass was performed. The main results were obtained through dynamic simulations which considered various disturbances in the feed stream, and demonstrated superior performance by the hot-vapor bypass system over the usual scheme proposed in literature, while evaluating the lntegral Absolute Error （IAE） norm as the control performance index.

关键词： Distillation Pressure control Hot-vapor bypass

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Effects of quantitative feed restriction and sex on carcass traits,meat quality and meat lipid profile of Morada Nova lambs

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Journal of Animal science and Biotechnology 2017年第4期8卷 992-1003页

作者： Thiago L.A.C.de Araújo Elzania s.pereira Ivone Y.Mizubuti Ana C.N.Campos Marília W.F.pereira Eduardo L.Heinzen Hilton C.R.Magalhaes Leilson R.Bezerra Luciano P da silva Ronaldo L.Oliveira department of Animal science Federal University of CearaFortaleza 60356001CearaBrazil department of Animal science State University of LondrinaLondrina 86051990ParanáBrazil Laboratory of sensory Analysis Agency for Agricultural Research(EMBRAPA-Tropical Agroindustry)Fortaleza 60511110CearáBrazil department of Animal science Campus Professora Cinobelina ElvasFederal University of PiauíBom Jesus 64900000PiauiBrazil department of Animal science School of Veterinary Medicine and Animal Science/Federal University of BahiaSalvador CityBahia State 40.170-110Brazil

Background: An experiment was conducted to evaluate the effects of feed restriction(FR) and sex on the quantitative and qualitative carcass traits of Morada Nova lambs. Thirty-five animals with an initial body weight of 14.5 ± 0.89 kg and age of 120 d were used in a completely randomized study with a 3 × 3 factorial scheme consisting of three sexes(11 entire males, 12 castrated males and 12 females) and three levels of feeding(ad libitum – AL and 30% and 60% FR).Results: Entire males presented greater hot and cold carcass weights(P strated males and females. However, the hot carcass yield was higher for females and castrated males than for entire males. Luminosity values were influenced(P sex, with entire males presenting higher values than castrated males and *** showed higher(P s of linoleic acid and arachidonic acid in the meat of the longissimus thoracis muscle. The meat of animals submitted to AL intake and 30% FR showed similar(P > 0.05) concentrations, and the concentrations of palmitic acid, palmitoleic acid, stearic acid, oleic acid and conjugated linoleic acid were higher(P se of animals with 60% FR. The meat of females had a higher ω6/ω3 ratio and lower h/H ratio, and females had greater levels of feeding. The meat of animals on the 60% FR diet had a greater ω6/ω3 ratio, lower h/H ratio and lower concentration of desirable fatty acids in addition to a greater atherogenicity index(AI) and thrombogenicity index(TI).Conclusion: Lambs of different sexes had carcasses with different quantitative traits without total influence on the chemical and physical meat characteristics. The lipid profile of the meat was less favorable to consumer health when the animals were female or submitted to 60% feed restriction.

关键词： Dietary restriction Fatty acid Hair sheep Lean meat semi-arid condition

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Molecule-based kinetic modeling by Monte Carlo methods for heavy petroleum conversion

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science China Chemistry 2013年第11期56卷 1608-1622页

作者： de OLIVEIRA Luís.pereira VERsTRAETE Jan J. KOLB Max IFP Energies nouvelles Rond-point de l'échangeur de Solaize-BP 369360 SolaizeFrance Laboratoire de Chimie cole Normale Supérieure69364 Lyon Cedex 07France

A methodology for kinetic modeling of conversion processes is *** proposed approach allows to overcome the lack of molecular detail of the petroleum fractions and to simulate the reactions of the process by means of a two-step *** the first step,a synthetic mixture of molecules representing the feedstock is generated via a molecular reconstruction method,termed sR-REM molecular *** the second step,a kinetic Monte Carlo method,termed stochastic simulation algorithm(ssA),is used to simulate the effect of the conversion reactions on the mixture of *** resulting methodology is applied to the Athabasca vacuum residue *** adequate molecular representation of the vacuum residue is obtained using the sR-REM *** reaction simulations present a good agreement with the laboratory data for Athabasca vacuum residue *** addition,the proposed methodology provides the molecular detail of the vacuum residue conversion throughout the reactions simulations.

关键词： Monte-Carlo molecular reconstruction kinetic modeling stochastic simulation algorithm vacuum residue hydrocracking

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Acetylcholinesterase and Cytotoxic Activity of Chemical Constituents of Clutia lanceolata Leaves and its Molecular Docking study

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Natural Products and Bioprospecting 2016年第6期6卷 267-278页

作者： Mehtab Parveen Faheem Ahmad Ali Mohammed Malla shaista Azaz Mahboob Alam Omer A.Basudan Manuela Ramos silva Pedro s.pereira silva department of Chemistry Aligarh Muslim UniversityAligarh 202002India Division of Bioscience Dongguk UniversityGyeongju 780-714Republic of Korea Pharmacognosy College of PharmacyKing Saud UniversityRiyadh 4451Saudi Arabia CFisUC Department of PhysicsUniversity of Coimbra3004-516 CoimbraPortugal

Phytochemical investigations of the ethanolic extract of leaves of Clutia lanceolata(Family:Euphorbiaceae)resulted in the isolation of four compounds viz.3,4-dihydroxy-2-methylbenzoic acid(1),2,20-dihydroxy-1,10-binaphthyl(2),1,3,8-trihydroxy-6-methylanthracene-9,10-dione(3)and 5-hydroxy-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,4,6-trien-3-one(4).Although all the isolated compounds were known but this was the first report from this plant *** structures were established on the basis of chemical and physical evidences *** analysis,FT-IR,1 H-NMR,13CNMR and mass spectral *** of compound 2 and 4 was further authenticated by single-crystal X-ray analysis and density functional theory *** isolated compounds(1–4)were screened for AChE enzyme inhibition assay in which compound 3 and 4 were found to be more potent AChE *** docking study of potent AChE inhibitor was performed to find the probable binding mode of the compounds into the active site of ***,the isolated compounds were also screened for in vivo cytotoxicity by brine shrimp lethality assay.

关键词： Clutia lanceolata X-ray crystallography AChE Molecular docking Cytotoxicity

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Chemical Profile of the sulphated saponins from the starfish Luidia senegalensis Collected as by-Catch Fauna in Brazilian Coast

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Natural Products and Bioprospecting 2018年第2期8卷 83-89页

作者： Marcelo Marucci pereira Tangerina Julia Pizarro Cesario Gerson Rodrigues Raggi pereira Tania Marcia Costa wagner Cotroni Valenti wagner Vilegas UNEsP-Univ Estadual Paulista Coastal campus of Sao VicentePraca Infante Dom Henrique s/nSao VicenteSP 11330-900Brazil Chemistry Institute Sao Paulo State University-UNESPAraraquara CampusProf.Francisco Degni55SPAraraquara 14800-060Brazil

The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are discarded because they do not have commercial *** order to try to add some value to these materials,we analyzed the chemical composition of the starfish Luidia senegalensis collected in the Brazilian coast as a consequence of the trawling fishery *** order to access their chemical composition,we used a combination of solid phase extraction(sPE)followed by ultra-high performance liquid chromatography coupled to electrospray ionization ion trap tandem mass spectrometry(UPLC-EsI-IT-Msn).Luidia sene-galensis contains asterosaponins,which are sulphated glycosilated steroids,containing five and six sugar moieties,in addition to *** study helped us to support the presence of important and potentially bioactive compounds in invertebrates associated to the by-catch fauna of the shrimp fishery,using a fast and efficient method.

关键词： Luidia senegalensis By-catch fauna Asterosaponins UPLC-Ms

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