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Distribution and origin of polycyclic aromatic hydrocarbons in surface sediments from an urban river basin at the Metropolitan Region of curitiba,Brazil

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Journal of Environmental sciences 2011年第6期23卷 904-911页

作者： Natalicio Ferreira Leite patricio peralta-Zamora Marco Tadeu Grassi instituto de tecnologia do paran(TEcpAR) 81350-010 CuritibaBrazil departamento de Química Universidade Federal do Parana'(UFPR)C.P.1908181531-990 CuritibaBrazil

The concentrations of 16 polycyclic aromatic hydrocarbons（pAHs） were determined in surface sediment samples from nine sites located at the iguau River Basin in the Metropolitan Region of curitiba,Brazil to evaluate their distribution and *** total concentration of the pAHs was greater for sediments from highly urbanized areas,while the sediments from the iraí Environmental protection Area（iraí EpA） showed significantly low *** sediments from the iguau and Barigui rivers were classified as highly contaminated,while those from the cercado and curralinho rivers were classified as moderately *** predominance of pAHs containing two to four aromatic rings in most of the samples suggested the direct input of raw sewage into the water resources ***[g,h,i]perylene,dibenzo[a,h]anthracene and indeno[1,2,3-cd]pyrene were predominant in sediments from the areas under the greatest urban and industrial *** correlation between thermodynamic stability and the kinetics of evolution presented by the isomeric pairs indicated that combustion is the predominant source of pAHs in the sediments because the combustion of fossil fuels affected most of the points evaluated,followed by combustion of biomass and eventually combustion of oil product *** general,the results showed that areas under strong urban influence,as well as the iraí EpA,receive contributions of pAHs from similar sources.

关键词： pAHs trace level analysis fiver sediment isomeric ratio igua^u River Basin

Assessing the estrogenic potency in a portuguese wastewater treatment plant using an integrated approach

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Journal of Environmental sciences 2010年第10期22卷 1613-1622页

作者： Mário s.Diniz Rita Maurício Mira petrovic Maria J.López de Alda Leonor Amaral isabel peres Damiá Barceló Fernando santana universidade Nova de Lisboa Faculdade de Ciencias e TecnologiaREQUIMTEDep.de Quimica universidade Nova de Lisboa Faculdade de Ciencias e TecnologiaDep.de Ciencias e Engenharia do Ambiente department of Environmental chemistry-iiQAB-csic c/Jordi Girona

The estrogenic potency of a wastewater treatment plant （WWTp） was evaluated using chemical and biological analyses, which showed that after the station treatment processes some of the selected endocrine disruptor compounds （EDcs） were still present in the treated effluent （e.g., bisphenol A, alkylphenols, estrone）. Thus, the most common endocrine EDcs were identified and quantified and the overall estrogenicity of the treated effluent assessed by integrating the results. Male goldfish （carassius auratus） were used as biological indicators in a 28-day experiment. vitellogenin （vtg）, gonadosomatic and hepatosomatic indices, steroids （17β-estradiol and 11-ketotestosterone） and histopathology were biomarkers used in fish to evaluate WWTp treated effluent estrogenicity, in combination with instrumental analyses. The results showed a significant increase （p 〈 0.01） in plasma and liver vtg, which were significantly correlated （r = 0.66; p 〈 0.01）. The gonadosmatic index was significantly （p 〈 0.01） reduced in exposed fish. The steroid analyses revealed significant elevations in 17β-estradiol and depressed 11-ketotestosterone concentrations. The histological examinations show changes in exposed fish gonads, such as regressed testes and in some cases （43% to 75%） the development of ovo-testis in fish exposed to 50% and 100% treated effluent.

关键词： carassius auratus endocrine disruptors vitellogenin steroids intersex

Nickel phosphonate MOF as efficient water splitting photocatalyst

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Nano Research 2021年第2期14卷 450-457页

作者： pablo salcedo-Abraira sergio M.F.vilela Artem A.Babaryk Maria cabrero-Antonino pedro Gregorio Fabrice salles sergio Navalon Hermenegildo Garcia patricia Horcajada iMdeA Energy Advanced Porous Materials Unit(APMU)Avda.Ramon de Ia Sagra 3E 28935 MostolesMadridSpain deparrtamento de quimica inorginica i.Fac.cc.quimicas Universidad Complutense de MadridAvda.Complutense s/n28040 MadridSpain departamento de quimica and instituto de tecnologia quimica(csic-upv) Universitat Politecnica de ValenciaC/Camino de Veras/n46022 ValenciaSpain institut charles Gerhardt Montpellier UMR 5253 CNRS UM ENSCMUniversite MontpellierPlace E.Bataillon34095 Montpellier Cedex 05France

A novel microporous two-dimensional(2D)Ni-based phosphonate metal-organic framework(MOF;denoted as iEF-13)has been successfully synthesized by a simple and green hydrothermal method and fully characterized using a combination of experimental and computational *** resolution by single-crystal X-ray diffraction reveals that iEF-13 crystallizes in the triclinic space group pi having bi-octahedra nickel nodes and a photo/electroactive tritopic phosphonate ***,this material exhibits coordinatively unsaturated nickel(ii)sites,free-p0_(3)H_(2)and-p0_(3)H acidic groups,a c0_(2)accessible microporosity,and an exceptional thermal and chemical ***,its in-deep optoelectronic characterization evidences a photoresponse suitable for *** this sense,the photocatalytic activity for challenging H_(2)generation and overall water splitting in absence of any co-catalyst using uv-vis irradiation and simulated sunlight has been evaluated,constituting the first report for a phosphonate-MOF ***-13 is able to produce up to 2,200 fimol of H_(2)per gram using methanol as sacrificial agent,exhibiting stability,maintaining its crystal structure and allowing its *** more,170μmol of H_(2)per gram were produced using iEF-13 as photocatalyst in the absence of any co-catalyst for the overall water splitting,being this reaction limited by the 0_(2)*** present work opens new avenues for further optimization of the photocatalytic activity in this type of multifunctional materials.

关键词： metal-organic framework phosphonates photocatalysis water splitting

Non-linear modeling of kinetic and equilibrium data for the adsorption of hexavalent chromium by carbon nanomaterials:Dimension and functionalization

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chinese Journal of chemical Engineering 2019年第4期27卷 912-919页

作者： Miguel de la Luz-Asunción Eduardo E.pérez-Ramírez Ana L.Martínez-Hernández victor M.castano víctor sánchez-Mendieta carlos velasco-santos Facultad de quimica Universidad Autonoma del Estado de Mexico Km. 12 de la carretera Toluca-Atlacomulco C.P. 50200 San Cayetano Toluca Estado de Mexico Mexico Tecnologico Nacional de Mexico-instituto Tecnologico de Queretaro Division de Estudios de Posgrado e Investigacion Av. Tecnologico s/n esq. GraL Mariano Escobedo Col. Centro Historico C.P. 76000 Santiago de Queretaro Queretaro Mexico centro de Fisica Aplicada y tecnologia Avanzada Universidad Nacional Autonoma de Mexico Boulevard Juriquilla 3001 Queretaro 76230 Mexico

The adsorption capacities for the removal of hexavalent chromium from aqueous solutions by six carbon nanomaterials have been evaluated. single-walled and multi-walled carbon nanotubes as received and after oxidation treatment, graphene oxide and reduced graphene oxide are the materials with different dimension and functionalization compared in this research. carbon nanotubes have been modified using hydrogen peroxide as oxidizing agent under microwave radiation. The oxidation treatment on carbon nanotubes has a positive effect increasing the adsorbent–adsorbate interaction. Rate-controlling mechanisms and equilibrium data are analyzed using non-linear models. Non-linear method is proposed as the most suitable method for determining the kinetic and equilibrium parameters. The values of adsorption energy(E) obtained from the Dubinin–Radushkevich isotherm,have been found around 0.371 and 0.870 k J·mol-1, indicating physical adsorption. Therefore, the pseudo-second order model represents better the kinetic experimental data. The results show that the Langmuir isotherm provides a slightly better fit to the experimental data compared with the Freundlich isotherm, indicating homogeneous distribution of active sites on carbon nanomaterials and monolayer adsorption. The separation factors RLare found in the range of 0–1, suggesting that the adsorption process is suitable for all adsorbents. The mechanisms for hexavalent chromium removal have been proposed as electrostatic interactions and hydrogen bonding.

关键词： carbon nanotubes Graphene Adsorption Hexavalent chromium Kinetic

improving the haploidization toolbox:Maternal factors take the stage

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Molecular plant 2023年第4期16卷 651-653页

作者： Maria Flores-Tornero Helena sapeta Jorg D.Becker instituto de tecnologia quimica e Biologica Universidade Nova de LisboaAv.daRepublica2780-157OeirasPortugal

plant breeders have a great interest in obtaining plants that are genetically homogeneous as quickly as possible,with high efficiency and at low *** approaches,including selfing or backcrossing,cannot provide *** technologies,however,offer a solution and are therefore the subject of intensive research,in particular during the last decade.

关键词： breed homogeneous quickly

More Transporters,More substrates:The Arabidopsis Major Facilitator superfamily Revisited

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Molecular plant 2019年第9期12卷 1182-1202页

作者： Maria Nino-Gonzalez Esther Novo-uzal Dale N.Richardson pedro M.Barros paula Duque instituto Gulbenkian de ciencia 2780-156 OeirasPortugal Genomics of plant stress unit ITQB NOVA-Instituto de Tecnologia Quimica e Biologica Antonio XavierUniversidade Nova de Lisboa2780-157 OeirasPortugal

The Major Facilitator superfamily(MFs)is ubiquitous in living organisms and represents the largest group of secondary active membrane *** plants,significant research efforts have focused on the role of specific families within the MFs,particularly those transporting macronutrients(c,N,and p)that constitute the vast majority of the members of this *** MFs families remain less explored,although a plethora of additional substrates and physiological functions have been ***,the lack of a systematic approach to analyzing the MFs as a whole has obscured the high diversity and versatility of these ***,we present a phylogenetic analysis of all annotated MFs domaincontaining proteins encoded in the Arab/dops/s fA?a//ana genome and propose that this superfamily of transporters consists of 218 members,clustered in 22 *** reviewing the available information regarding the diversity in biological functions and substrates of Arab/dops/s MFs members,we provide arguments for intensified research on these membrane transporters to unveil the breadth of their physiological relevance,disclose the molecular mechanisms underlying their mode of action,and explore their biotechnological potential.

关键词： Arabidopsis thaliana membrane transport MFs transporters phylogenetic analysis

XBAT35, a Novel Arabidopsis RiNG E3 Ligase Exhibiting Dual Targeting of its splice isoforms, is involved in Ethylene-Mediated Regulation of Apical Hook curvature

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Molecular plant 2012年第6期5卷 1295-1309页

作者： sofia D. carvalho Rita saraiva Teresa M. Maia isabel A. Abreu paula Duquea instituto Gulbenkian de ciencia Rua da Quinta Grande 6 2780-156 Oeiras Portugal instituto de tecnologia quimica e Biologica Universidade Nova de Lisboa Av. da Republica 2780-157 Oeiras Portugal

The Arabidopsis XBAT35 is one of five structurally related ankyrin repeat-containing Really interesting New Gene （RiNG） E3 ligases involved in ubiquitin-mediated protein degradation, which plays key roles in a wide range of cel- lular processes. Here, we show that the XBAT35 gene undergoes alternative splicing, generating two transcripts that are constitutively expressed in all plant tissues. The two splice variants derive from an exon skipping event that excludes an in-frame segment from the XBAT35 precursor mRNA, giving rise to two protein isoforms that differ solely in the presence of a nuclear localization signal （NLs）. Transient expression assays indicate that the isoform lacking the NLs localizes in the cytoplasm of plant cells, whereas the other is targeted to the nucleus, accumulating in nuclear speckles. Both isoforms are functional E3 ligases, as assessed by in vitro ubiquitination assays. Two insertion mutant alleles and RNA-interference （RNAi） silencing lines for XBAT35 display no evident phenotypes under normal growth conditions, but exhibit hyper- sensitivity to the ethylene precursor 1-aminocyclopropane-l-carboxylate （Acc） during apical hook exaggeration in the dark, which is rescued by an inhibitor of ethylene perception. independent expression of each XBAT35 splice variant in the mutant background indicates that the two isoforms may differentially contribute to apical hook formation but are both functional in this ethylene-mediated response. Thus, XBAT35 defines a novel player in ethylene signaling involved in negatively regulating apical hook curvature, with alternative splicing controlling dual targeting of this E3 ubiquitin ligase to the nuclear and cytoplasmic compartments.

关键词： alternative splicing apical hook Arabidopsis thaliana ethylene signaling RiNG E3 ligase ubiquitination.

single droplet drying of detergents:Experimentation and modelling

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particuology 2021年第5期19卷 35-47页

作者： Borja Hernandez Rosa Mondragon Mark A.pintoa Leonor Hernandez J.Enrique Julia Juan carlos Jarque sergio chiva Mariano Martin Newcastle innovation centre Procter&Gamble R&DNewcastle upon TyneUK departamento de ingenieria quimica y Textil.universidad de salamanca SalamancaSpain departamento de ingenieria Mecanica y construccion Universitat Jaume ICastellon de la PlanaSpain instituto de tecnologia ceramica Universitat Jaume ICastellon de la PlanaSpain

This study evaluates the single droplet drying(sDD)of *** data are used to validate a theoretical multistage *** experiments are carried out in an acoustic levitator analysing six different detergent formulations at 393 *** work is completed by developing a model based on conservation *** model is composed of the three stages observed in the drying *** the first stage,an external surface drying stage occurs until the surface is saturated and the crust is *** the next stage,the drying rate is governed by diffusion through the *** the same time,the particle heats up until boiling conditions are achieved in the core of the *** this point,the third stage *** the final stage,the droplet core is in boiling conditions which are governed by the pressure drop through the crust and the concentration of *** model has been evaluated for the different formulations being flexible to predict the drying of different mixtures with good accuracy.

关键词： Drying single droplet Acoustic levitator detergents

sKELETON sTRucTuREs iN pOROus siLicON

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SKELETON STRUCTURES IN POROUS SILICON