RESUMO
Traffic-related emissions include gas and particles that can alter air quality and affect human and environmental health. Limited studies have demonstrated that particulate debris thrown off from brakes are toxic to higher plants. The acute phytotoxicity of brake pad wear debris (BPWD) investigated using cress seeds grown in soil contaminated with increasing concentrations of debris. Two types of pads were used: a commercially available phenol based pad and an innovative cement-based pad developed within of the LIFE+ COBRA project. The results suggested that even through the BPWD generated by the two pads were similar in and morphology, debris from traditional pads were more phytotoxic than that from cementitious pads, causing significant alterations in terms of root elongation and loss of plasma membrane integrity.
Assuntos
Lepidium sativum/efeitos dos fármacos , Material Particulado/toxicidade , Emissões de Veículos/toxicidade , Automóveis , Germinação/efeitos dos fármacos , Humanos , Material Particulado/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Testes de ToxicidadeRESUMO
The detailed analysis of the time resolved luminescence of a specifically designed fluorescent molecular rotor enables the direct monitoring of the self-assembly of a poly(N,N-dimethylacrylamide)-block-polystyrene (PDMA-b-PS) copolymer into core-corona nanoparticles. Comparison with bulk PS indicates hard confinement of the micelle core, due to the solvation of the hydrophilic PDMA corona.
RESUMO
Highly efficient plastic based single layer Luminescent Solar Concentrators (LSCs) require the design of luminophores having complete spectral separation between absorption and emission spectra (large Stokes shift). We describe the design, synthesis and characterization of a new perylene dye possessing Stokes shift as high as 300 meV, fluorescent quantum yield in the LSC slab of 70% and high chemical and photochemical stability.
Assuntos
Corantes/química , Substâncias Luminescentes/química , Perileno/química , Energia Solar , Corantes/síntese química , Estrutura Molecular , Perileno/síntese química , Processos FotoquímicosRESUMO
A new oxyiminopyrazole-based ytterbium chelate enables NIR emission upon UV excitation in colorless single layer luminescent solar concentrators for building integrated photovoltaics.
Assuntos
Quelantes/química , Substâncias Luminescentes/química , Energia Solar , Itérbio/química , Cor , Modelos Moleculares , Conformação Molecular , Polimetil Metacrilato/química , Espectrofotometria InfravermelhoRESUMO
We present relevant results dealing with the transparency/optical nonlinearity trade-off in high-frequency electro-optic applications. The very simple, stable and high optical gap chromophore, the zwitterion 1-methyl-4-(tetrazol-5-ate)pyridinium, represents the best transparency/optical nonlinearity trade-off so far described in the literature. We rationalize this remarkable performance in the framework of the Bond Length Alternation theory by means of a multidisciplinary approach including: single crystal X-ray structure, Electric Field Induced Second-Harmonic Generation, solvatochromism, electrochemistry and thermal analyses.