56 research outputs found
Highly Stable and Reactive Platinum Single Atoms on Oxygen Plasma-Functionalized CeO<sub>2</sub> Surfaces: Nanostructuring and Peroxo Effects
Atomically dispersed precious metals on oxide supports have recently become increasingly interesting catalytic materials. Nonetheless, their non-trivial preparation and limited thermal and environmental stability constitutes an issue for their potential applications. Here we demonstrate that an oxygen plasma pre-treatment of the ceria (CeO2 ) surface serves to anchor Pt single atoms, making them active and resistant towards sintering in the CO oxidation reaction. Through a combination of experimental results obtained on well-defined CeO2 films and theory, we show that the O2 plasma causes surface nanostructuring and the formation of surface peroxo (O22-) species, favoring the uniform and dense distribution of isolated strongly bonded Pt2+ atoms. The promotional effect of the plasma treatment was further demonstrated on the powder Pt/CeO2 catalysts. We believe that plasma functionalization can be applied to other metal/oxide systems to achieve tunable and stable catalysts with a high density of active sites
Highly Stable and Reactive Platinum Single Atoms on Oxygen Plasma-Functionalized CeO<sub>2</sub> Surfaces: Nanostructuring and Peroxo Effects
Atomically dispersed precious metals on oxide supports have recently become increasingly interesting catalytic materials. Nonetheless, their non-trivial preparation and limited thermal and environmental stability constitutes an issue for their potential applications. Here we demonstrate that an oxygen plasma pre-treatment of the ceria (CeO2 ) surface serves to anchor Pt single atoms, making them active and resistant towards sintering in the CO oxidation reaction. Through a combination of experimental results obtained on well-defined CeO2 films and theory, we show that the O2 plasma causes surface nanostructuring and the formation of surface peroxo (O22-) species, favoring the uniform and dense distribution of isolated strongly bonded Pt2+ atoms. The promotional effect of the plasma treatment was further demonstrated on the powder Pt/CeO2 catalysts. We believe that plasma functionalization can be applied to other metal/oxide systems to achieve tunable and stable catalysts with a high density of active sites
Optical and electrostatic potential investigations of electrical breakdown phenomena in a low-pressure gas discharge lamp
Describing dialogue between persons with profound intellectual and multiple disabilities and direct support staff using the scale for dialogical meaning making
Background The dialogical approach of meaning making forms a rich and renewing theoretical perspective to study communication between presymbolic communicators and their interaction partners. The aim of this study is to investigate whether an observation scale based on the dialogical theory, the Scale for Dialogical Meaning Making (S-DMM), has potential to describe these communicative interactions. Methods Eighteen videotaped observations of persons with profound intellectual and multiple disabilities and their support staff were coded using the S-DMM and a consensus-rating procedure. Results Sufficient inter-rater agreement and an acceptable range in scores confirm the usefulness of the S-DMM. Strong sub-scale intercorrelations were identified. The quantitative scores and the qualitative arguments supporting the ratings, demonstrate how the S-DMM aids to significantly describe staff-client dialogue. Conclusions Using the S-DMM to describe dialogue with persons with profound intellectual and multiple disabilities appears to be promising. The value of the S-DMM and its consensus-rating procedure are reflected upon and discussed with regard to implications for research and practice
The importance of growth/no growth models for specific organisms within the food industry
Haloalkaline Bioconversions for Methane Production from Microalgae Grown on Sunlight
Daelman MRJ, Sorokin D, Kruse O, van Loosdrecht MCM, Strous M. Haloalkaline Bioconversions for Methane Production from Microalgae Grown on Sunlight. TRENDS IN BIOTECHNOLOGY. 2016;34(6):450-457.Microalgal biomass can be converted to biofuels to replace nonsustainable fossil fuels, but the widespread use of microalgal biofuels remains hampered by the high energetic and monetary costs related to carbon dioxide supply and downstream processing. Growing microalgae in mixed culture biofilms reduces energy demands for mixing, maintaining axenic conditions, and biomass concentration. Furthermore, maintaining a high pH improves carbon dioxide absorption rates and inorganic carbon solubility, thus overcoming the carbon limitation and increasing the volumetric productivity of the microalgal biomass. Digesting the microalgal biomass anaerobically at high pH results in biogas that is enriched in methane, while the dissolved carbon dioxide is recycled to the phototrophic reactor. All of the required haloalkaline conversions are known in nature
Effect of Climate Change in Wastewater Treatment Plants: Reviewing the Problems and Solutions
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