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Entropy model to assess sediment resuspension probability and trap efficiency of small dams

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International Journal of Sediment Research 2022年第5期37卷 675-686页

作者： Francisco Jairo Soares Pereira antonio Viana da silva Filho José Wellington batista Lopes José Carlos de Araújo Department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. Despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these *** objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(July 2018-July 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model’s tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

Miscibility of Poly(hydroxybutyrate)/Poly(vinyl alcohol)Melt Blends Plasticized With Glycerol

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Journal of Renewable Materials 2019年第4期7卷 325-333页

作者： Deliane da silva Cabral antonio JoséFelix Carvalho Department of Materials Engineering São Carlos School of EngineeringUniversity of São PauloAv.João Dagnone110013563-120São Carlos-SP-Brazil

Poly(hydroxybutyrate)/poly(vinyl alcohol)(PHB/PVA)blends plasticized with glycerol were prepared by melt blending of PHB and glycerol plasticized *** PHB/PVA-glycerol compositions were 90:10,75:25 and 50:50 w/w,being the concentration of glycerol in the PVA mixture of 10 wt%.The blends were characterized by infrared spectroscopy,dynamic-mechanical thermal analysis,and scanning electron microscope of the fragile fractured *** results showed one single phase blend,indicating miscibility corroborated by the presence of a single glass transition *** blending method proved to be an efficient way to tune PHB properties keeping its biodegradable nature since both PVA and glycerol are fully biodegradable materials.

关键词： Blend miscibility melt processing poly(hydroxybutyrate) poly(vinyl alcohol)

A Finite Element Study of the Influence of Graphite Nodule Characteristics on a Subsurface Crack in a Ductile Cast Iron Matrix under a Contact Load

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Computer Modeling in Engineering & Sciences 2018年第10期117卷 59-71页

作者： Guilherme Suguinoshita Carlos Henrique da silva Marco antonio Luersen Department of Mechanical Engineering Federal University of Technology-Parana(UTFPR)Rua Deputado Heitor Alencar Furtado5000CEP 81280-340CuritibaBrazil

This paper describes a study of the effects of graphite nodule characteristics on a subsurface crack in austempered ductile iron(ADI).A representative specimen of ADI,subjected to sliding contact load,is modeled using finite elements aiming to obtain the shear stress intensity factor(KII).The parameters varied were(i)the nodule diameter(two different values were considered),(ii)the distance between the nodule and the tip of the crack and(iii)the position of the load relative to the tip of the *** results of the numerical simulations show that the smaller diameter nodule has a larger influence on KII,suggesting a higher contact fatigue crack propagation rate in the material with the smaller *** results are the opposite of those observed in experimental studies and would appear to indicate that other factors should be also considered to ensure realistic estimates of the contact fatigue strength of ADI.

关键词： Austempered ductile iron subsurface crack stress intensity factor finite element analysis graphite nodule

Equity issues and the PeCUS index:an indirect analysis of community severance

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Geo-Spatial Information Science 2020年第4期23卷 293-304页

作者： daniela Vanessa Rodriguez Lara antonio Nelson Rodrigues da silva Department of Transportation Engineering São Carlos School of EngineeringUniversity of São PauloSão PauloBrazil

Urban barriers are often a consequence of the unplanned expansion of transport infrastructures,housing growth nearby existing transport infrastructures,and the vehicular traffic *** process,also known as“community severance”,is a problem that affects the travel patterns of the population and causes negative impacts to adjacent communities,but it is not easy to *** an alternative to the costly technologies and restricted-access data sometimes used to analyze urban barriers,we propose an analytical approach that assesses community severance levels by classifying the quality of Pedestrian Crossings on Urban Streets(the PeCUS index).Additionally,the approach is used to identify possible inequities nearby the different classification groups regarding demographic *** used the chi-square(χ^(2))test of independence and the standardized Pearson residuals to indicate deficits and excesses of residents regarding the demographic characteristics studied surrounding the urban *** found the following evidences of associations:residents with low-income or those aged up to 19 tend to live close to the worst crossings,whereas residents with permanent mobility constraints or the elderly tend to live near the crossings with the best ***,the study shows that the assessment of community severance by the analysis of the PeCUS index is ***,it reveals that the distribution of residents surrounding the distinct classes of quality of crossings is equitable for vulnerable social groups,except for low-income or young residents.

关键词： Community severance transport barriers pedestrian crossings equity open data geographic information systems(GIS)

Special Issue on 15th Brazilian Polymer Conference:Biopolymers,Eco-Friendly and Biodegradable Polymers and Other Topics Related to Polymeric Materials Derived from Renewable Materials

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Journal of Renewable Materials 2021年第4期9卷 599-600页

作者： antonio Aprigio da silva Curvelo antonio José Felix Carvalho daniel Pasquini São Carlos Institute of Chemistry University of São PauloSão Carlos13566-590-SPBrazil São Carlos School of Engineering University of São PauloSão Carlos13563-120-SPBrazil Institute of Chemistry Federal University of UberlândiaUberlândia38400-902MGBrazil

This issue of Journal of Renewable Materials is a special issue dedicated to the 15th Brazilian Polymer Conference(15th CBPol)which was held in Bento Gonçalves,Rio Grande do Sul State,Brazil,from 27 to 31 October,2019[1].CBPol is the main scientific forum in the field of polymer science and technology in *** conference has been held biannually since 1991 and in this event had almost 900 participants mainly from Brazil,but also from Argentina,Chile,Peru,USA,Canada,Belgium,France,Great Britain,Portugal and Spain,with 60%students and 40%professionals.A total of 1,100 papers from 2725 authors were presented,from which 25%(280 papers)was in the field of Biomaterials showing the importance of these materials which are in general based on renewable *** 280 works were developed mainly by researchers from Brazilian institutions(universities and research institutes),mainly from the south and southeast regions of the *** subject of more than 70%of the works was dedicated on vegetal raw materials,medicinal applications,packaging and composite materials.

关键词： materials showing annually

Litter removal impacts on soil biodiversity and eucalypt plantation development in the seasonal tropics

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Journal of Forestry Research 2023年第3期34卷 735-748页

作者： Jonas Inkotte Barbara Bomfim Sarah Camelo da silva Marco Bruno Xavier Valadão Márcio Gonçalves da Rosa Roberta batista Viana Alcides Gatto Reginaldo SPereira Department of Forestry Engineering University of BrasiliaBrasíliaDistrito FederalBrazil Climate and Ecosystem Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA SESI/SENAI Social Service Industry Santa Catarina StateChapecóBrazil

The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic ***,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and *** two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area *** litterfall rates in juvenile and mature stands did not change with litter removal over the study *** litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control *** wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in *** years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to *** the mature stand,total cation exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional scaling ordination revealed an increased homogeneity in epigeic fauna where litter was ***,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control p

关键词： Cerrado Nutrient cycling Soil ecology Soil epigeic fauna Plantation management

Pulp and Paper from Sugarcane:Properties of Rind and Core Fractions

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Journal of Renewable Materials 2018年第2期6卷 160-168页

作者： Lísias Pereira Novo Julien Bras Mohamed Naceur Belgacem antonio Aprigio da silva Curvelo Department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone 110013563-120Sao CarlosSao PauloBrazil Department of Physical Chemistry Sao Carlos Institute of ChemistryUniversity of Sao PauloAv.Trabalhador Sao Carlense 40013560-970Sao CarlosSao PauloBrazil Grenoble Alpes University LGP2F-38000 GrenobleFrance CNRS LGP2F-38000 GrenobleFrance

Two distinct lignocellulosic fractions(rind and core)can be obtained through a physical separation of sugarcane *** presenting differences in morphology,both fractions can be employed to produce pulps and *** pulps and paper sheets produced from the core and rind fractions were characterized by their chemical composition,physical properties and mechanical *** pulps obtained from the core presented a higher amount of fines,lower drainage ability and rendered denser and stiffer *** pulps from the rind,which have a higher content of fibers and higher degree of polymerization,produced sheets with higher air permeability and water *** paper sheets presented mechanical and physical properties comparable to commercial papers and papers from different cellulosic *** different properties exhibited by the papers produced from each fraction allow their use for distinct purposes,and expands the opportunities in the context of sugarcane biorefinery.

关键词： Sugarcane core and rind fractions papermaking pulp and paper

Multi-stage block freeze concentration via gravitational method applied to increase of the nutritional content of Morinda citrifolia ***

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Food Bioscience 2023年第1期51卷 985-994页

作者： Edipo da silva Almeida Mateus antonio Knapp Juliana De Gregori da Rocha dachamir Hotza Debora de Oliveira Department of Chemical Engineering and Food Engineering(EQA) Federal University of Santa Catarina(UFSC)88040-970FlorianopolisSCBrazil

The processing of Morinda citrifolia fruit normally results in a large number of waste leaves that hold many bioactive compounds with nutritional and pharmacological *** work aimed to evaluate the effects of a multi-stage block freeze concentration(BFC)via gravitational method on the physicochemical properties of the leaf extract(noni tea).The results in solid retention showed fractions almost 7 times most concentrated than the initial *** addition,when compared to the initial content,the BFC process showed an efficiency higher than 90%in the retention of phenolic *** in liquid chromatography allowed the detection and quantification of phenolic compounds,in which the total amount increased by more than 1000%in relation to the initial content after each BFC ***,it was also possible to observe a significant increase in the antioxidant activity of the concentrated product after the simulated in vitro digestion *** was concluded that using a non-thermal,sustainable,low-cost processing,promoted the obtaining of concentrated fractions with high biological and nutritional values with promising properties for application in the development of functional foods from agroindustrial wastes.

关键词： Morinda citrifolia Block freeze concentration Phenolic compounds Antioxidant profile In vitro digestion Functional food

Engineering Improved Photosynthesis in the Era of Synthetic Biology

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Plant Communications 2020年第2期1卷 1-17页

作者： Willian batista-silva Paula da Fonseca-Pereira Auxiliadora Oliveira Martins Agustin Zsogon Adriano Nunes-Nesi Wagner L.Araujo Departamento de Biologia Vegetal Universidade Federal de Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Much attention has been given to the enhancement of photosynthesis as a strategy for the optimization of crop *** traditional plant breeding is most likely reaching a plateau,there is a timely need to accelerate improvements in photosynthetic efficiency by means of novel tools and biotechnological *** emerging field of synthetic biology offers the potential for building completely novel pathways in predictable directions and,thus,addresses the global requirements for higher yields expected to occur in the 21st ***,we discuss recent advances and current challenges of engineering improved photosynthesis in the era of synthetic biology toward optimized utilization of solar energy and carbon sources to optimize the production of food,fiber,and fuel.

关键词： photosynthesis synthetic biology genetic engineering yield improvement targeted manipulation