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ZnO/CeO_(2)/carbon xerogel composites with direct Z-scheme heterojunctions:Enhancing photocatalytic remediation of 4-chlorophenol under visible light

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Journal of Rare Earths 2024年第2期42卷 314-322,I0003页

作者： nicolas Perciani de Moraes Maite Birkett de Campos Sanmartin Robson da Silva Rocha Abner de Siervo Marcos Roberto de Vasconcelos Lanza D.Amaranatha Reddy Lianqing Yu Liana Alvares rodrigues Escola de Engenharia de Lorena-EEL/USP Estrada Municipal do Campinho S/NCEP 12602-810LorenaSao PauloBrazil Institute of Physics"Gleb Wataghin" Applied Physics DepartmentState University of Campinas13083-859CampinasSPBrazi Instituto de Quimica de Sao Carlos Universidade de Sao PauloAv.Trab.Sao Carlense400-Parque Arnold SchimidtSao CarlosSP13566-590Spain Department of Sciences Indian Institute of Information Technology Design and ManufacturingKurnoolAndhra Pradesh518007India School of Materials Science and Engineering China University of PetroleumQingdao266580China

This paper aims to create visible light driven ternary photocatalysts using zinc oxide(ZnO),cerium(IV)oxide(CeO_(2)),and carbon xerogel(CX) as constituent materials.The use of CeO_(2) is based on the creation of direct-Z-scheme heterojunctions with the ZnO and the consequent diminishing of charge recombination,whereas the carbon xerogel inclusion is predicted to minimize bandgap energy,decrease electro n-hole reco mbination,and boost specific surface area.Furthermo re,the choice of the black-wattle tannin as a carbonaceous precursor was targeted at the development of an environmentally friendly and affordable composite.The existence of the hexagonal phase of zinc oxide and cubic structure of the cerium(IV) oxide in the ternary material was confirmed by X-ray diffractometry and X-ray photoelectron spectroscopy,with the latter also suggesting chemical bonding between the ZnO and the CX due to the creation of zinc oxycarbide complexes.The inclusion of the carbon xerogel provokes a significant modification in the morphology of the ternary material,resulting in an increased surface area and smaller particle aggregates.The CX/ZnO-CeO_(2) ternary composite obtains the highest photocatalytic efficiency among all the materials studied,degrading 100% of 4-chlorophenol under simulated sunlight and 68% under visible radiation,after 5 h.The increased photocatalytic activity can be attributed to the formation of direct Z-scheme heterojunctions between the semiconductors,higher visible light response,and higher specific surface area,as evidenced by the results obtained by active radical scavenging,chronoamperometry,diffuse reflectance spectroscopy,and N_(2) adsorption-desorption isotherms.

关键词： Zinc oxide Cerium(Ⅳ)oxide Carbon xerogel Photocatalysis Direct Z-scheme heterojunction 4-Chlorophenol Rare earths

Nano-fried-eggs： Structural, optical, and magnetic characterization of physically prepared iron-silver nanoparticles

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Nano Research 2018年第11期11卷 6074-6085页

作者： Julien Ramade nicolas Troc Olivier Boisron Michel Pellarin Marie-Ange Lebault Emmanuel Cottancin Vitor T. A. Oiko Rafael Cabreira Gomes Varlei rodrigues Matthias Hillenkamp Univ. Lyon Universitd Claude Bernard Lyon I CNRS UMR5306 Institut Lumiee Matiee t=-69622 Villeurbanne France Instituto de F[sica Gleb Wataghin UNICAMP CP 6165 13083-970 Campinas SP Brazil

The prospect of combining both magnetic and plasmonic properties in a single nanoparticle promises both valuable insights on the properties of such systems from a fundamental viewpoint and numerous possibilities for technological applications. However, the combination of two of the most prominent metallic candidates—iron and silver—has presented numerous experimental difficulties because their thermodynamic properties impede miscibility and even coalescence. Herein, we present the thorough characterization of physically prepared Fe50Ag50 nanoparticles embedded in carbon and silica matrices via electron microscopy, optical spectroscopy, magnetometry and synchrotron-based X-ray spectroscopy. Iron and silver segregate completely into structures resembling fried eggs, with a nearly spherical, crystallized silver part surrounded by an amorphous structure of iron carbide or oxide, depending on the environment of the particles. Consequently, the particles exhibit both plasmonic absorption corresponding to the silver nanospheres in an oxide environment and a reduced but measurable magnetic response. The suitability of such nanoparticles for technological applications is discussed from the viewpoint of their high chemical reactivity with their environment.

关键词： nanoalloy bimetallic nanoparticles iron silver FeAg optical spectroscopy magnetometry

Does a giant tortoise taxon substitute enhance seed germination of exotic fleshy-fruited plants?

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Journal of Plant Ecology 2013年第1期6卷 57-63页

作者： Annika Waibel Christine J.Griffiths nicolas Zuel Bernhard Schmid Matthias Albrecht Institute of Evolutionary Biology and Environmental Studies University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland Mauritian Wildlife Foundation Grannum RoadVacoasMauritius School of Biological Sciences University of BristolWoodland RoadBristol BS81UGUK Present address:Mediterranean Institute for Advanced Studies Department of Biodiversity and Conservation (‘Consejo Superior de Investigaciones Cientı´ficas-Universitat de les Illes Balears’)Miquel Marques 2107190 EsporlesMallorcaBalearic IslandsSpain

Aims The use of exotic species as taxon substitutes to restore lost ecological interactions is currently hotly debated.Aldabrachelys gigantea giant tortoises have recently been introduced to three islands in the Mascarene archipelago(Ile aux Aigrettes,Round Island and rodrigues)to resurrect herbivory and seed dispersal functions once performed by extinct giant tortoises.However,potential unintended impacts by frugivore substitutes on native ecosystems,e.***.whether they will facilitate the germination of exotic plant species,are largely unknown.We investigated whether A.gigantea introduced to rodrigues in 2006 could enhance the germination percentage of four widespread fleshy-fruited exotic species on the island.Using germination trials to forecast unintended impacts that could arise from the introduction of a frugivorous taxon substitute enables conservation managers to limit potential adverse negative interactions before they occur.Methods In germination trials that ran over 4 months,we investigated the effects of ingestion(gut passage and deposition in faeces)by subadult and adult A.gigantea on the germination percentage of four exotic fleshy-fruited plant species introduced to rodrigues.We fed fruits of these plant species to sub-adult and adult A.gigantea to test how variation in age and size of the frugivore would affect seed germination.Feeding of distinctly coloured plastic pellets together with the fruits allowed us to test for individual tortoise effects on seed germination.Important Findings Ingestion by A.gigantea increased the percentage of seeds germinating of Mimusops coriacea and Lantana camara,but not percentage of germination of Veitchia merrillii or Wikstroemia indica.Seeds were more likely to germinate following ingestion by sub-adult rather than adult tortoises,which may be a consequence of the shorter gut passage time observed for sub-adults.Our results demonstrate that introduced frugivorous taxon substitutes could facilitate germination of exotic and invasive plants and highlight the need fo

关键词： ecological analogues exotic species invasion gut passage plant–frugivore interactions seed germination

Punica granatum Leaf Lipophilic Fraction Favours Mortality by Attenuating Inflammation in Mice with Polymicrobial Sepsis

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Journal of Pharmacy and Pharmacology 2019年第7期7卷 355-367页

作者： Nagila Caroline Fialho Sousa Isabella Fernandes da Silva Figueiredo Mizael Calacio de Araujo Elaine Pereira de Andrade Thais Costa Alves Bruna Letícia Rosa da Silva Domingos Magno Santos Pereira Saulo JoseFigueiredo Mendes Joao Francisco Silva rodrigues Jaqueline Pessoa Pontes Simone Aparecida Teixeira AndreAlvares Marques Vale Marcus Vinicius Dias-Souza Lidio Goncalves Lima-Neto Vera Lucia dos Santos Ana Paula Azevedo-Santos Marcelo nicolas Muscara Valerio Monteiro-Neto Andrea de Souza Monteiro Luis Claudio Nascimento da Silva Elizabeth Soares Fernandes Programa de Pos-graduacao Universidade CEUMARua JosueMontellon°1RenascencaSao LuisMA 65075-120Brazil Departamento de Farmacologia Universidade de Sao PauloAv.Prof.Lineu Prestesn°1524Sala 326ButantanSao PauloSP 05508-900Brazil Programa de Pos-graduacao em Ciências em Saude Universidade Federal do MaranhaoAvenida dos Portuguesesn°1966BacangaSao LuisMA 65080-805Brazil Departamento de Microbiologia Universidade Federal de Minas GeraisAv.Antonio Carlosn°6627PampulhaBelo HorizonteMG 31270-901Brazil Departamento de Patologia Universidade Federal do MaranhaoAvenida dos Portuguesesn°1966BacangaSao LuísMA 65080-805Brazil

Punica granatum L.possesses known antimicrobial and anti-inflammatory actions.Preparations of different parts of this plant have been commonly used in the folk medicine to prevent and treat infections;and studies have supported the use of P.granatum extracts for this purpose.However,little is known of the effects of P.granatum-derived fractions in severe infectious diseases such as sepsis.Here,we investigated the actions of the hexane fraction(HF),rich in lipophilic compounds,obtained from the leaves of this plant,in a murine model of polymicrobial sepsis.Oral pre-treatment with HF increased mortality in septic mice.The same animals presented with lower levels of interleukin-6,nitric oxide and hydrogen peroxide in their peritoneal lavage samples than vehicle mice.HF also increased polymorphonuclear cell accumulation in to the peritoneum of mice with sepsis.Macrophage-derived nitric oxide upon lipopolysaccharide stimuli was markedly reduced by incubation with HF.Diterpenes,triterpenes,phytosterols,vitamin E and ascorbyl palmitate were detected in the HF.These results indicate that P.granatum leaf lipophilic fractions may worsen sepsis outcome.This effect may be associated with its bioactive compounds which act synergistically or not,increasing sepsis mortality in vivo.

关键词： P.granatum infection inflammation