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Soot combustion; ceria; Ternary mixed oxide; cordierite coating; Diesel particulate filter

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Journal of Environmental Sciences 2018年第11期30卷 58-68页

作者： Leandro Fontanetti Nascimento Juliana Fonseca Lima paulo cesar de sousa filho Osvaldo Antonio Serra department of chemistry FFCLRP University of Sao Paulo 14040-901 Ribeirao Preto Sao Paulo Brazil Institute of chemistry Rio de Janeiro State University 20550-900 Rio de Janeiro Rio de Janeiro Brazil Institute of chemistry Uniuersity of Campinas 13083-970 Campinas Silo Paulo Brazil center of-Natural and Human Sciences Federal Uniuerty of ABC 09210-580 Santo Andre Sao Paulo Brazil

We report the application of a solid lanthanum-ceria-zinc catalyst in the catalytic regeneration of diesel particulate filters （DPF） in diesel engines. We synthesized a ceO2- ZnO-La2O3 （ce-Zn-La） mixed oxide by a lactic acid-mediated sol-gel method, which efficiently coated cordierite substrates for soot capture and combustion. We studied the effects of La loading on the physicochemical and catalytic properties of ce-Zn mixed oxide during lowtemperature soot combustion processes. We characterized the synthesized catalysts by X-ray diffraction （XRD）, Fourier-transform infrared spectroscopy （FTIR）, N2 adsorption, Raman spectroscopy, oxygen storage capacity （OSG）, and scanning and transmission electron microscopy （SEM and TEM）. Thermogravimetric and differential thermal analysis （TGA/DTA） confirmed that the catalysts effectively reduced the soot oxidation temperature. The ternary ce-Zn-La mixed oxide catalyst with ce/Zn/La atomic ratio of 2：1：0.5 had the highest catalytic activity and promoted soot oxidation at temperatures below 390℃. This indicated that the large number of oxygen vacancies in the catalyst structure generated oxygen species at low temperatures. Raman spectroscopy measurements revealed the presence of oxygen vacancies and lattice defects in ce-Zn-La samples, which were key parameters concerning the stability and redox properties of the prepared catalysts.

关键词： Soot combustion ceria Ternary mixed oxide cordierite coating Diesel particulate filter

Adipose-derived stem cells and knee osteoarthritis:New perspectives,old concerns

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World Journal of Orthopedics 2024年第11期15卷 1001-1006页

作者： Eduardo B de sousa Josépaulo A Gabbi filho Vinicius S Gameiro Leandra S Baptista department of General and Specialized Surgery Fluminense Federal UniversityRio de Janeiro 24070-090Brazil department of Orthopaedics Quinta D’Or HospitalRio de Janeiro 20941-150Brazil Duque de caxias campus Prof Geraldo cidade Federal University of Rio de JaneiroRio de Janeiro 25065-050Brazil

In this editorial,we comment on the paper by Muthu et al published in the recent issue of the *** editorial review focusses on the use of adipose-derived stem cells(ADScs)in knee osteoarthritis *** discuss the differences between the stromal vascular fraction and microfragmented adipose tissue and highlight the results of clinical studies comparing both treatments and the use of hyaluronic acid,platelet-rich plasma,and bone marrow aspirate *** use of expanded ADScs is also discussed;moreover,concerns regarding treatment with ADScs,particularly the heterogeneity of published studies and the need to standardize protocols to explore clinical potential is explored.

关键词： Adipose tissue Adipose-derived stem cells Stromal vascular fraction Knee Osteoarthritis Microfragmented adipose tissue

Fault Location Approach to Distribution Networks Based on custom State Estimator

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Journal of Modern Power Systems and clean Energy 2023年第6期11卷 1878-1889页

作者： Luis F.Ugarte Madson c.de Almeida Luís H.T.Bandória IEEE department of Systems and Energy State University of CampinasSão Paulo 13083-970Brazil

This paper presents a properly designed branchcurrent based state estimator(BcBSE)used as the main core ofan accurate fault location approach(FLA)devoted to distribution *** to the approaches available in the literature,it uses only a limited set of conventional measurementsobtained from smart meters to accurately locate faults at busesor branches without requiring measurements provided by phasor measurement units(PMUs).This is possible due to themethods used to model the angular reference and the faultedbus,in addition to the proper choice of the weights in the stateestimator(SE).The proposed approach is based on a searchingprocedure composed of up to three stages:①the identificationof the faulted zones;②the identification of the bus closest tothe fault;and③the location of the fault itself,searching onbranches connected to the bus closest to the ***,this paper presents a comprehensive assessment of the proposedapproach,even considering the presence of distributed generation,and a sensitivity study on the proper weights required bythe SE for fault location purposes,which can not be found inthe *** show that the proposed BcBSE-basedFLA is robust,accurate,and aligned with the requirements ofthe traditional and active distribution networks.

关键词： Active distribution network branch current based state estimator fault location smart meter

Atlas of precipitation extremes for South America and Africa based on depth-duration-frequency relationships in a stochastic weather generator dataset

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International Soil and Water conservation Research 2023年第4期11卷 726-742页

作者： Andrew Fullhart David c.Goodrich Menberu B.Meles paulo Tarso S.Oliveira cristiano das Neves Almeida Joséc.de Araújo Shea Burns Southwest Watershed Research center USDA-ARS 2000 E.Allen Rd.TucsonAZ85719United States Sustainable Agricultural Water Systems Unit USDA-ARS 239 Hopkins RoadDavisCA95616United States Faculty of Engineering Architecture and Urbanism and GeographyUniversidade Federal de Mato Grosso do SulCampo GrandeMS79070-900Brazil Water Resources and Environmental Engineering Laboratory Universidade Federal da ParaíbaJoao PessoaPB58051-900Brazil department of Agricultural Engineering campus do Pici Fortaleza Universidade Federal do CearáFortaleza60020-181Brazil

Information about extreme rainfall is lacking in regions of South America and *** study attempts to fill this scientific gap by use of a gridded parameterization for the stochastic weather generator,cLIGEN,to map depth-duration-frequency(DDF)*** of 500-year point-scale precipitation time series generated at each grid point allowed maps of return period precipitation to be produced for a se-lection of sixteen durations ranging from 10-min to 1-year and for nine return periods from 2 to 500 *** generalized extreme value(GEV)probability distribution was fitted for all durations,and given GEV quantiles,an interpolation method was applied to produce maps at 0.1° resolution that better resolve small-scale spatial climate *** addition to uncertainties related to GEV fitting,this study quantifies prediction intervals based on ground *** validation was important for identifying biases in cLIGEN,although uncertainties were not always satisfactorily defined due to sampling design and other *** daily/multi-day durations,100 stations with daily observations and ≥50-year records were selected for validation against the 0.1° cLIGEN map series,resulting in a median and average absolute error of 13%and 16%,*** sub-daily durations,prediction errors were larger *** analogy using available *** established the degree of bias in cUGEN for sub-daily durations,and three records in Brazil with high temporal resolutions were used to confirm that applied bias adjustments resulted in error ranges similar to the daily/multi-day *** atlas is freely available for study of extreme precipitation.

关键词： Africa depth-duration-frequency Extreme precipitation South America

determination of critical state line(cSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： Nilo cesar consoli João Vítor de Azambuja carvalho Alexia cindy Wagner Hugo carlos Scheuermann filho Inácio carvalho Pedro Pazzoto cacciari João paulo de sousa Silva civil Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral development centre VALE S.A.Santa LuziaMG33040-900Brazil department of civil Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behaviour during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behaviour of iron ore tailings in a spectrum of confining pressures broader than the reported in previous studies.A series of consolidated drained(cD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curved critical state line(cSL)in both specific volume(ν)-logarithm of mean effective stress(p′)and deviatoric stress(q)-mean effective stress(p′)planes,and different responses in the deviatoric stress-axial strain-volumetric strain curves were *** inverse S-shaped equation was proposed to represent the silty-sandy tailings'behaviour up to high pressures onν-lnp′*** proposed equation provides a basis for enhancing constitutive models and considers the evolution of the grading up to severe loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure levels.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material critical state soil mechanics High confining pressures Particle breakage

Assessing the inter-annual variability of separation distances around odour sources to protect the residents from odour annoyance

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Journal of Environmental Sciences 2019年第5期31卷 11-24页

作者： Marlon Brancher Martin Piringer Davide Franco paulo Belli filho Henrique de Melo Lisboa Gunther Schauberger Postgraduate Program in Environmental Engineering (PPGEA) Federal University of Santa Catarina (UFSC) 88040900 Florianopolis Brazil.CAPES Foundation scholarship holder (main author) Brazilian Ministry of Education Brasilia Brazil WG Environmental Health Department of Biomedical Sciences University of Veterinary Medicine ViennaVeterinarplatz1 A-1210Vienna Austria central Institute for Meteorology and Geodynamics Hohe Warte 38 A-1190 Vienna Austria

In recent years, there has been a growing concern about potential impacts on public health and wellbeing due to exposure to environmental odour. Separation distances between odour-emitting sources and residential areas can be calculated using dispersion models, as a means of protecting the neighbourhood from odour annoyance. This study investigates the suitability of using one single year of meteorological input data to calculate reliable direction-dependent separation distances. Accordingly, we assessed and quantified the inter-annual variability of separation distances at two sites with different meteorological conditions, one in Brazil and the other in Austria. A 5-year dataset of hourly meteorological observations was used for each site. Two odour impact criteria set in current regulations were selected to explore their effect on the separation distances. The coefficient of variation was used as a statistical measure to characterise the amount of annual variation. Overall,for all scenarios, the separation distances had a low degree of inter-annual variability(mean coefficient of variation values from 8% to 21%). Reasonable agreements from year to year were therefore observed at the two sites under investigation, showing that one year of meteorological data is a good compromise to achieve reliable accuracy. This finding can provide a more cost-effective solution to calculate separation distances in the vicinity of odour sources.

关键词： Environmental odour Odour annoyance Impact assessment Dispersion modelling Regulatory criteria Separation distance

3D segmentation and visualization of lung and its structures using cT images of the thorax

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Journal of Biomedical Science and Engineering 2013年第11期6卷 1099-1108页

作者： Pedro P.Reboucas filho paulo cesar cortez Victor Hugo c.de Albuquerque Industry Area Federal Institute of Education Science and Technology of CearaMaracanauBrazil Teleinformatic Engineering department Federal University of CearáFortalezaBrazil Graduate Program in Applied Informatics University of FortalezaFortalezaBrazil

computing systems have been playing an important role in various medical fields, notably in image diagnosis. Studies in the field of computational Vision aim at developing techniques and systems capable of detecting various illnesses automatically. What has been highlighted among the existing exams that allow diagnosis aid and the application of computing systems in parallel is computed Tomography (cT). cT enables the visualization of internal organs, such as the lung and its structures. computational Vision systems extract information from the cT images by segmenting the regions of interest, and then recognize and identify details in those images. This work focuses on the segmentation phase of cT lung images with singularity-based techniques. Among these methods are the region growing (RG) technique and its 3D RG variations and the thresholding technique with multi-thresholding. The 3D RG method is applied to lung segmentation and from the 3D RG segments of the lung hilum, the multi-thresholding can segment the blood vessels, lung emphysema and the bones. The results of lung segmentation in this work were evaluated by two pulmonologists. The results obtained showed that these methods can integrate aid systems for medical diagnosis in the pulmonology field.

关键词： 3D Region Growing Lungs segmentation cOPD Pulmonary Structure Visualization computed Tomography

Mechanical behavior of iron ore tailings under standard compression and extension triaxial stress paths

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第7期15卷 1883-1894页

作者： Alexia cindy Wagner João paulo de sousa Silva João Vítor de Azambuja carvalho Ana Luisa cezar Rissoli Pedro Pazzoto cacciari Helder Mansur chaves Hugo carlos Scheuermann filho Nilo cesar consoli Universidade Federal do Rio Grande do Sul Porto Alegre90035-190Brazil Mineral development centre Vale S.A.Santa Luzia33040-900Brazil department of civil Geological and Mining EngineeringPolytechnique MontrealMontrealH3C 3A7Canada

The disposal of mining tailings has increasingly focused on the use of dry *** structures offer more security since they use filtered and compacted *** of the construction method and the heights achieved,the material that compounds the structure can be subjected to different stress paths along the failure *** theoretical framework considered in the design of these structures generally is the critical state soil mechanics(cSSM).However,the data in the literature concerning the uniqueness of critical state line(cSL)is still controversial as the soil is subjected to different stress *** respect to tailings,this question is even more *** paper studies two tailings with different gradings due to the beneficial processes over extension and compression paths.A series of drained and undrained triaxial tests was conducted over a range of initial densities and stress *** the q-p'plane,different critical stress ratio(M)values were obtained for compression and extension stress ***,the critical state friction angle is very similar with a slightly higher critical state friction angle for extension *** stress path dependent cSLs were obtained in the n-lnp0 plane with the extension tests below the cSL defined in *** the fines content,the studied tailings presented very similar M and critical state friction angle ***,the fines content af-fects the volumetric behavior of the studied tailings and the cSLs on the n-lnp0 plane shift downwards with the increasing fines content for compression and extension *** relation to dilatancy analysis,the fines content did not present an evident influence on the dilatancy of the ***,different values of mean stress ratio N were obtained between compression and extension tests and can corroborate the existence of non-unique cSLs for these materials.

关键词： Iron ore tailings(IOTs) Dry stacking critical state soil mechanics Extension tests Stress path

Rainfall erosivity and erosivity density through rainfall synthetic series for Sao paulo State,Brazil:Assessment,regionalization and modeling

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International Soil and Water conservation Research 2022年第3期10卷 355-370页

作者： David Bruno de sousa Teixeira Roberto Avelino cecílio Joao paulo Bestete de Oliveira Laura Thebit de Almeida Gabrielle Ferreira Pires department of Agricultural Engineering Federal University of ViçosaViçosaMG36570-900Brazil department of Forest and Wood Sciences Federal University of Espírito SantoJer^onimo MonteiroES29550-000Brazil Federal Institute of Espírito Santo Campus AlegreAlegreES29520-000Brazil

Rainfall is the main cause of erosion of Brazilian soils,which makes assessing the rainfall erosivity factor(RE)and the erosivity density(ED)fundamental for soil and water ***,the objectives of this study were:i)to estimate the RE and ED for Sao paulo State,Brazil,using synthetic series of pluviographic data;ii)to define homogeneous regions regarding rainfall erosivity;and iii)to generate regression models for rainfall erosivity estimates in each of the homogeneous *** series of pluviographic data were initially obtained on a sub-daily scale from the daily rainfall records of 696 rainfall *** RE values were then estimated from the synthetic rainfall data,and ED was calculated from the relationship between erosivity and rainfall *** and annual maps for RE and ED were *** clustering analysis was used to define homogeneous regions in terms of rainfall erosivity,and regionalized regression models for estimating RE were *** results demonstrate high spatial variability of RE in Sao paulo,where the highest annual values were observed in the coastal *** to March concentrate approximately 60%of the intra-annual *** highest values of annual ED were observed in regions with intense agricultural *** definition of five homogeneous regions concerning the rainfall erosive potential evidenced distinct seasonal patterns of the spatial distribution of ***,the high predictive accuracy of the regionalized models obtained characterizes them as essential tools for reliable estimates of rainfall erosivity,and contribute to better soil conservation planning.

关键词： Soil erosion Stochastic weather generator Homogeneous regions Modified Fournier index Regression models