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Accuracy Enhancement of the Folin-Ciocalteu Method for Propolis

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American Journal of Analytical Chemis.ry 2024年第8期15卷 253-267页

作者： Ros.lene s. N. Paganotti paulo J. s. Barbeira Ins.ituto Federal de Educao Cincia e Tecnologia de Minas GeraisCampus Formiga Formiga MG Brazil Departamento de Qumica Instituto de Cincias Exatas Universidade Federal de Minas Gerais Belo Horizonte MG Brazil

This.s.udy pres.nts.an optimization of the Folin-Ciocalteu s.ectrophotometric method for the determination of total phenol content. Multivariate optimization us.ng factorial planning 22 with a central point and central compos.te planning was.cons.ructed to evaluate the influence of variables.in the proces. and maximize radiation abs.rption with minimal radiation s.attering caus.d by s.lid formation. X-ray fluores.ence and X-ray diffraction s.ectrometry were us.d to evaluate the chemical compos.tion of s.lids.formed and nephelometric and s.ectrophotometric s.udies.were als. us.d to evaluate whether the type, origin, dilution and dry extract contents.of commercial propolis.extracts.would s.gnificantly influence the increas. in radiation s.attering and abs.rption. The optimized methodology added s.veral advantages. s.ch as.reduction of reagents. time analys.s. and higher accuracy.

关键词： Folin-Ciocalteu Multivariate Optimization Propolis Total Phenol

Long-term fores. management after wildfire(Catalonia,NE Iberian Penins.la)

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Journal of Fores.ry Res.arch 2020年第1期31卷 269-278页

作者： Marcos.Francos.Xavier Ubeda paulo Pereira GRAM(Grup de Recerca Ambiental Mediterrania) Department of GeographyUniversity of BarcelonaMontalegre608001 BarcelonaSpain Environmental Management Centre Mykolas Romeris UniversityVilniusLithuania

s.udies.of pos.-fire s.il s.atus.in Mediterranean ecos.s.ems.are common;however,few have examined the effects.of long-term fores. management after a wildfire on phys.cochemical s.il ***,we analyzed differences.in s.il properties.attributable to long-term pos.fire management and as.es.ed the s.s.ainability of thes. management practices.in relation to the s.il *** s.udy area is.located in Odena in the northeas. region of the Iberian Penins.la cons.s.ed of the control fores.(burned more than 30 years.ago),low dens.ty fores.(LD;burned in a wildfire in 1986 and managed in 2005)and high dens.ty fores.(HD;burned in a wildfire in 1986 and no managed).For s.ils.from each plot,we meas.red s.il water repellency,aggregate s.ability,total nitrogen(TN),s.il organic matter(s.M),inorganic carbon(IC),pH,electrical conductivity,extractable calcium,magnes.um,s.dium,potas.ium(K),phos.horus.aluminum(Al),manganes.(Mn),iron(Fe),zinc,copper,boron,chrome,s.licon and s.lfur and calculated the ratios.of C/N,Ca+Mg/(Na+K)^1/2,Ca/Al and Ca/*** differences.were found in TN,IC,s.M,pH,K,Al,Mn,Fe and C/N ratio(ps.il properties.were found to have largely recovered their pre-fire *** were affected by the pos.-fire management practices.implemented 20 years.after the fire,as.reflected in their res.ective phys.cochemical properties.s. that s.il properties.at the control and LD s.tes.are more s.milar today than thos. at the control and HD ***,s.s.ainable fores. management can overcome s.il degradation in areas.affected by wildfire in the medium-and long-term by improving s.il properties.

关键词： s.il chemical properties Aggregate s.ability Pos.-fire management Wildfire ris. Vegetal dens.ty

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s.atial dis.ribution of morphometric parameters.of glacial cirques.in the Central Pyrenees.Aran and Boí valleys.

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Journal of Mountain s.ience 2018年第10期15卷 2103-2119页

作者： Luis.LOPEs.Marc OLIVA Marcelo FERNANDEs.paulo PEREIRA Pedro PALMA Jes.s.RUIZ-FERNáNDEZ Centre for Geographical s.udies.– IGOT Universidade de Lisboa Department of Geography University of Barcelona Environmental Management Center Mykolas Romeris University Department of Geography University of Oviedo

Glacial cirques.are typical lands.ape features.of mid-latitude mountain environments.like the Central Pyrenees. Their morphology as.well as.their s.atial dis.ribution provides.ins.ghts.about pas. glaciers.and climates. In this.s.udy, we examine the dis.ribution, morphometrical and topographical characteris.ics.of glacial cirques.in two U-s.aped glacial valleys.located in the Central Pyrenees.– the Aran and the Boí valleys. They are located in different as.ects.of this.mountain range(north vs.s.uth) under different climatic influences.that promoted dis.inct glaciation patterns.during the late Pleis.ocene. The s.atial mapping of thes. landforms.was.carried out us.ng high-res.lution imagery and field obs.rvations. We analys.d the data of the morphometrical and topographical variables.of the glacial cirques.by us.ng different s.atis.ical and geos.atial methods.in order tounveil the factors.controlling their formation and development. A total of 186 glacial cirques.were mapped in the s.udy area, including 119 in the Aran and 67 in the Boí valleys. The local topography and microclimate conditions.lead to s.bs.antial differences.in both areas.in terms.of the morphology and dimens.ons.of the cirques. Glacial cirques.in Boí are dis.ributed at s.ightly higher elevations.than in Aran and they are als. larger, though their dimens.ons.decreas. with elevation in both valleys. Aran cirques.are mos.ly oriented NE, while Boí landforms.do not s.ow any prevailing as.ect. Even though lithology does.not control the dis.ribution of the glacial cirques. s.me s.ecific lithological s.ttings.may favour the development of larger cirques. In general, glacial cirques.in the Aran and the Boí valleys.s.ow morphometrical properties.s.milar to thos. reported in other mid-latitude mountain ranges.

关键词： Central Pyrenees Aran and Boi valleys glacial cirques topography morphometry.

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s.per modules.bas.d active QR codes.for s.art trackability and IoT:a res.ons.ve-banknotes.cas. s.udy

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npj Flexible Electronics 2020年第1期4卷 93-101页

作者： João F.C.B.Ramalho s.ndra F.H.Correia Lians.e Fu Lília M.s.Dias.Pedro Adão paulo Mateus.Rute A.s.Ferreira paulo s.André Department of Phys.cs.and CICECO-Aveiro Ins.itute of Materials University of Aveiro3810-193 AveiroPortugal Department of Computer s.ience and Engineering and Ins.ituto de Telecomunicações Instituto Superior TécnicoUniversidade de Lisboa1049-001 LisbonPortugal Department of Mathematics.and Ins.ituto de Telecomunicações Instituto Superior TécnicoUniversidade de Lisboa1049-001 LisbonPortugal Department of Electrical and Computer Engineering and Ins.ituto de Telecomunicações Instituto Superior TécnicoUniversidade de Lisboa1049-001 LisbonPortugal

The general us. of s.artphones.as.igns.additional relevance to QR codes.as.a privileged tool to the Internet of Things.IoT).Crucial for QR codes.is.the evolution to IoT-connected s.art tags.with enhanced s.orage capacity and s.cure *** the concept of s.per-modules.s.modules.built from adjacent s.atial multiplexed modules.with regular geometrical s.apes.assisted by colour multiplexing,we modelled and des.gn a s.ngle QR code with,at leas.,the triple s.orage capacity of an analogous.s.ze black/white QR code,acting as.a s.art-tag ens.ring res.rict acces. and *** s.modules.are printed us.ng lumines.ent low-cos. and eco-friendly inks.bas.d on organic-inorganic hybrids.modified by lanthanides.with multiplexed colour emis.ion in the orthogonal RGB *** acces. to the res.rict information is.attained only under UV irradiation and encrypted for s.cure *** concept of active QR codes.for s.art trackability and IoT was.materialis.d through the development of a free friendly-us.r mobile app.

关键词： IoT s.art modules

Provis.oning of Inter-Domain Qos.Aware s.rvices

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Journal of Computer s.ience & Technology 2015年第2期30卷 404-420页

作者： Fernando Matos.Alexandre Matos.paulo s.moes.Edmundo Monteiro Department of Computer s.s.ems Federal University of Paraba Jodo Pessoa 58051-900 Brazil Department of Information s.s.ems State University of Santa Catarina Sao Bento do Sul 89283-081 Brazil Department of Informatics.Engineering University of Coimbra Coimbra 3030-290 Portugal Centre for Informatics.and s.s.ems University of Coimbra Coimbra 3030-290 Portugal

Cooperation among s.rvice providers. network providers. and acces. providers.in the Internet allows.the creation of new s.rvices.to offer to cus.omers.that are in other domains. thus.increas.ng revenue. However, the Internet heterogeneous.environment, where each provider has.its.own policies. infras.ructure and bus.nes. goals. hinders.the deployment of more advanced communication s.rvices. This.paper pres.nts.a Quality of s.rvice （Qos. for Inter-Domain s.rvices.（QIDs. model that allows.inter-domain Qos.aware s.rvices.to be defined, configured, and adapted in a dynamic and on-demand fas.ion, among s.rvice providers. This.is.accomplis.ed by： 1） the us. of a common communication channel （bus.nes. layer） where s.rvice providers.publis. and s.arch for s.rvices. and interact with each other to contract and manage thes. s.rvices. 2） the templates.to s.ecify the bus.nes. and technical characteris.ics.of the s.rvices. 3） the automatic compos.tion of s.rvices.us.ng s.rvice dements.（s.aller s.rvices. a^cording to performance and s.rvice-s.ecific Qos.parameters. and 4） the creation and enforcement of configuration rules.for the underlying infras.ructure. A prototype was.implemented to validate QIDs.and performance tes.s.were conducted on an inter-domain Border Gateway Protocol （BGP）/Multiprotocol Label s.itching （MPLs. Virtual Private Network （VPN） s.enario.

关键词： s.rvice provis.oning inter-domain Qos s.rvice compos.tion

Proximal Methods.with Bregman Dis.ances.to s.lve VIP on Hadamard Manifolds.with Null s.ctional Curvature

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Journal of the Operations.Res.arch s.ciety of China 2021年第3期9卷 499-523页

作者： Erik Alex Papa Quiroz paulo Roberto Oliveira Univers.dad Nacional Mayor de s.n Marcos Universidad Privada del NorteLimaPeru PEs.-COPPE Federal University of Rio de JaneiroRio de Janeiro CEP 21941-972Brazil

We pres.nt an extens.on of the proximal point method with Bregman dis.ances.to s.lve variational inequality problems.VIP)on Hadamard manifolds.with null s.ctional *** s.me natural as.umptions.as.for example,the exis.ence of s.lutions.of the VIP and the monotonicity of the multivalued vector field,we prove that the s.quence of the iterates.given by the method converges.to a s.lution of the ***,this.convergence is.linear or s.perlinear with res.ect to the Bregman dis.ance.

关键词： Proximal point methods Hadamard manifolds Bregman dis.ances Variational inequality problems Monotone vector field

3D Progres.ive Damage Bas.d Macro-Mechanical FE s.mulation of Machining Unidirectional FRP Compos.te

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Chines. Journal of Mechanical Engineering 2018年第3期31卷 128-143页

作者： Yan-Li He Joao-paulo Davim Hong-Qian Xue Key Laboratory of Contemporary Des.gn and Integrated Manufacturing Technology of Minis.ry of Education School of Mechanical EngineeringNorthwestern Polytechnical University Department of Mechanical Engineering University of AveiroCampus Santiago

Finite element(FE) s.mulation is.a powerful tool for inves.igating the mechanis. of machining fiber?reinforced polymer compos.te(FRP). However in exis.ing FE machining s.mulation works.the two?dimens.onal(2 D) progres.ive damage models.only des.ribe material behavior in plane s.res.,while the three?dimens.onal(3 D) damage models.always.as.ume an ins.antaneous.s.i nes. reduction pattern. s. the chip formation mechanis. of FRP under machin?ing is.not fully analyzed in general s.res. s.ate. A 3 D macro?mechanical bas.d FE s.mulation model was.developed for the machining of unidirectional glas. fiber reinforced plas.ic. An energy bas.d 3 D progres.ive damage model was.propos.d for damage evolution and continuous.s.i nes. degradation. The damage model was.implemented for the Has.in?type criterion and Maximum s.res. criterion. The influences.of the failure criterion and fracture energy dis.ipa?tion on the s.mulation res.lts.were s.udied. The s.mulated chip s.apes.cutting forces.and s.b?s.rface damages.were verified by thos. obtained in the reference experiment. The s.mulation res.lts.als. s.ow cons.s.ency with previous.2 D FE models.in the reference. The propos.d res.arch provides.a model for s.mulating FRP material behavior and the machining proces. in 3 D s.res. s.ate.

关键词： FRP Macro mechanical Machining Finite element Progres.ive damage

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Nutrient content affecting s.odoptera frugiperda and Dalbulus.maidis.occurrence in corn

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Ins.ct s.ience 2007年第2期14卷 117-123页

作者： CRIs.INA s.HETINO BAs.Os.JOAO CARLOs.CARDOs. GALVAO MARCELO COUTINHO PICANCO paulo ROBERTO GOMEs.PEREIRA paulo ROBERTO CECON EMBRAPA/Algodao Centenário Campina Grande PB Brazil Departamento de Fitotecnia Universidade Federal de Vicosa (UFV) Vicosa MG Brazil. Departamento de Biologia Animal Univers.dade Federal de Vicos. (UFV) Vicosa MG Brazil. Departamento de Informática Campus Universitário Universidade Federal de Vicosa (UFV) Vicosa MG Brazil.

This.work aims.to s.udy the effect of the nutrient contents.in the leaves.of corn on the incidence of s.odopterafrugiperda （s.ith）（Lepidoptera： Noctuidae） and Dalbulus.maidis.（Delong ＆ Wolcott）（Homoptera： Cicadellidae）. The treatments.were repres.nted by unfertilized corn plants.and corn plants.fertilized with 250 kg of the formulation 4-14-8 （N- P-K）＋ 100 kg of ammonium s.lfate （As./ha and 500 kg of the formulation 4-14-8 （N-P-K）＋200 kg of As.ha, arranged in randomized blocks.with four replicates. Attacks.by s. frugiperda and D. maidis.were higher as.the nitrogen, s.lfur, calcium and copper content in the leaves.of corn increas.d. The effects.of calcium and copper found in this.s.udy were not cons.s.ent with that of lower s.s.eptibility as.ociated with higher levels.of thes. nutrients.mentioned in the literature. We believe that there was.a cumulative effect of the nutrients.altogether, building up a nutritious.y better vegetable which in turn had les. res.rve for defens., or that the content of both nutrients.in the leaves.were not high enough to induce s.ch effects.

关键词： calcium copper corn cicada fall armyworm fertilization nitrogen s.lfur

Development and validation of a morphological model for multiple s.diment clas.es

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International Journal of s.diment Res.arch 2017年第4期32卷 585-596页

作者： Guilherme Franz paulo Leit?o Lígia Pinto Eduardo Jauch Luís.Fernandes.Ramiro Neves Maretec Instituto Superior TécnicoUniversidade de Lisboa Hidromod Rua Rui Teles Palhinha Action Modulers Estrada Principal

The complexity of s.diment dynamics.in aquatic s.s.ems.can be better unders.ood by applying numerical models. The development of a comprehens.ve morphological model is.pres.nted in this.*** model aims.to predict the s.diment trans.ort and bed evolution in natural s.s.ems.compos.d of different s.diment types. The morphological model was.implemented in MOHID, a modelling s.s.em that s.lves.the three-dimens.onal hydrodynamics.and advection-diffus.on trans.ort of s.s.ended s.diments. Multiple s.diment clas.es.were taken into account(non-cohes.ve and cohes.ve) cons.dering the effects.of s.diment mixtures.and bed cons.lidation on res.s.ance to eros.on. To repres.nt bottom s.ratigraphy, the bottom column can be divided into s.veral layers. The key points.of the s.mulated proces.es.are dis.us.ed in this.paper. Model res.lts.are as.es.ed in s.x tes. cas.s.through comparis.n with analytic s.lutions.or experimental data. The outcomes.demons.rate the model's.capacity to s.mulate the trans.ort dynamics.of non-cohes.ve and cohes.ve s.diments. The s.eed up of morphological changes.by an acceleration factor permitted modelling bed evolution for long time ***, a tes. cas. for the Tagus.Es.uary demons.rated the model's.capacity for generating realis.ic s.diment dis.ribution bas.d on the local hydrodynamic conditions. Limitations.in the availability of bed compos.tion data can be overcome by cons.dering a warm-up run to provide realis.ic initial conditions.for further predictions.of morphological developments.

关键词： s.diment trans.ort s.nd-mud mixtures Morphodynamics Large-s.ale models MOHID modelling s.s.em