9 research outputs found

    Synthesis of sub-5 nm Co-doped SnO2_2 nanoparticles and their structural, microstructural, optical and photocatalytic properties

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    A swift chemical route to synthesize Co-doped SnO2_2 nanopowders is described. Pure and highly stable Sn1−x_{1-x}Cox_xO2−ή_{2-\delta} (0 ≀\le x ≀\le 0.15) crystalline nanoparticles were synthesized, with mean grain sizes < 5 nm and the dopant element homogeneously distributed in substitutional sites of the SnO2_2 matrix. The UV-visible diffuse reflectance spectra of the Sn1−x_{1-x}Cox_xO2−ή_{2-\delta} samples reveal red shifts, the optical bandgap energies decreasing with increasing Co concentration. The Urbach energies of the samples were calculated and correlated with their bandgap energies. The photocatalytic activity of the Sn1−x_{1-x}Cox_xO2−ή_{2-\delta} samples was investigated for the 4-hydroxylbenzoic acid (4-HBA) degradation process. A complete photodegradation of a 10 ppm 4-HBA solution was achieved using 0.02% (w/w) of Sn0.95_{0.95}Co0.05_{0.05}O2−ή_{2-\delta} nanoparticles in 60 min of irradiation.Comment: 29 pages, 2 tables, 10 figure

    Perceptions of the impact of the COVID-19 pandemic on the work of science journalists: global perspectives

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    The article presents the results of a survey of science journalists from six world regions about their work during the COVID-19 pandemic. The responses show perception of increasing workload for most participants. Local scientists and peer-reviewed articles are the main sources. According to the respondents, scientists have become more available during the pandemic. The use of preprint articles was a frequent practice, but a considerable proportion declared they did not adopt different procedures when reporting them. Most also said they take fake news into account when writing their stories.info:eu-repo/semantics/publishedVersio

    Public communication by research institutes compared across countries and sciences: Building capacity for engagement or competing for visibility?

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    Leading academic institutions, governments, and funders of research across the world have spent the last few decades fretting publicly about the need for scientists and research organisations to engage more widely with the public and be open about their research. While a global literature asserts that public communication has changed from a virtue to a duty for scientists in many countries and disciplines, our knowledge about what research institutions are doing and what factors drive their 'going public' is very limited. Here we present the first cross-national study of N = 2,030 research institutes within universities and large scientific organisations in Brazil, Germany, Italy, Japan, the Netherlands, Portugal, the United Kingdom, and the United States of America. We find that institutes embrace communication with non-peers and do so through a variety of public events and traditional news media-less so through new media channels-and we find variation across countries and sciences, yet these are less evident than we expected. Country and disciplinary cultures contribute to the level of this communication, as do the resources that institutes make available for the effort; institutes with professionalised staff show higher activity online. Future research should examine whether a real change in the organisational culture is happening or whether this activity and resource allocation is merely a means to increase institutional visibility

    Uranus Pathfinder: exploring the origins and evolution of Ice Giant planets

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    The “Ice Giants” Uranus and Neptune are a different class of planet compared to Jupiter and Saturn. Studying these objects is important for furthering our understanding of the formation and evolution of the planets, and unravelling the fundamental physical and chemical processes in the Solar System. The importance of filling these gaps in our knowledge of the Solar System is particularly acute when trying to apply our understanding to the numerous planetary systems that have been discovered around other stars. The Uranus Pathfinder (UP) mission thus represents the quintessential aspects of the objectives of the European planetary community as expressed in ESA’s Cosmic Vision 2015–2025. UP was proposed to the European Space Agency’s M3 call for medium-class missions in 2010 and proposed to be the first orbiter of an Ice Giant planet. As the most accessible Ice Giant within the M-class mission envelope Uranus was identified as the mission target. Although not selected for this call the UP mission concept provides a baseline framework for the exploration of Uranus with existing low-cost platforms and underlines the need to develop power sources suitable for the outer Solar System. The UP science case is based around exploring the origins, evolution, and processes at work in Ice Giant planetary systems. Three broad themes were identified: (1) Uranus as an Ice Giant, (2) An Ice Giant planetary system, and (3) An asymmetric magnetosphere. Due to the long interplanetary transfer from Earth to Uranus a significant cruise-phase science theme was also developed. The UP mission concept calls for the use of a Mars Express/Rosetta-type platform to launch on a Soyuz–Fregat in 2021 and entering into an eccentric polar orbit around Uranus in the 2036–2037 timeframe. The science payload has a strong heritage in Europe and beyond and requires no significant technology developments
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