1,577 research outputs found
Mobility of antimony, arsenic and lead at a former mine, Glendinning, Scotland
Elevated concentrations of antimony (Sb), arsenic (As) and lead (Pb) in upland organic-rich soils have resulted from past Sb mining activities at Glendinning, southern Scotland. Transfer of these elements into soil porewaters was linked to the production and leaching of dissolved organic matter and to leaching of spoil material. Sb was predominantly present in truly dissolved (< 3 kDa) forms whilst As and Pb were more commonly associated with large Fe-rich/organic colloids. The distinctive porewater behaviour of Sb accounts for its loss from deeper sections of certain cores and its transport over greater distances down steeper sections of the catchment. Although Sb and As concentrations decreased with increasing distance down a steep gully from the main spoil heap, elevated concentrations (~ 6-8 and 13-20 μg L− 1, respectively) were detected in receiving streamwaters. Thus, only partial attenuation occurs in steeply sloping sections of mining-impacted upland organic-rich soils and so spoil-derived contamination of surface waters may continue over time periods of decades to centuries
Strategies for producing biochars with minimum PAH contamination
With the aim to develop initial recommendations for production of biochars with minimal contamination with polycyclic aromatic hydrocarbons (PAHs), we analysed a systematic set of 46 biochars produced under highly controlled pyrolysis conditions. The effects of the highest treatment temperature (HTT), residence time, carrier gas flow and typical feedstocks (wheat / oilseed rape straw pellets (WSP), softwood pellets (SWP)) on 16 US EPA PAH concentration in biochar were investigated. Overall, the PAH concentrations ranged between 1.2 and 100 mg kg-1. On average, straw-derived biochar contained 5.8 times higher PAH concentrations than softwood-derived biochar. In a batch pyrolysis reactor, increasing carrier gas flow significantly decreased PAH concentrations in biochar; in case of straw, the concentrations dropped from 43.1 mg kg-1 in the absence of carrier gas to 3.5 mg kg-1 with a carrier gas flow of 0.67 L min-1; for woody biomass PAHs concentrations declined from 7.4 mg kg-1 to 1.5 mg kg-1 with the same change of carrier gas flow. In the temperature range of 350-650°C the HTT did not have any significant effect on PAH content in biochars, irrespective of feedstock type, however, in biochars produced at 750°C the PAH concentrations were significantly higher. After detailed investigation it was deduced that this intensification in PAH contamination at high temperatures was most likely down to the specifics of the unit design of the continuous pyrolysis reactor used. Overall, it was concluded that besides PAH formation, vaporisation is determining the PAH concentration in biochar. The fact that both of these mechanisms intensify with pyrolysis temperature (one increasing and the other one decreasing the PAH concentration in biochar) could explain why no consistent trend in PAH content in biochar with temperature has been found in the literature
Review of Social Work Education : To What Extent Should Social Work Education have a Stronger Focus on Community Development and Engagement?
How is community development and community engagement currently taught within social work programmes in Scotland? How might this be strengthened across existing programmes as a means to support implementation of current Scottish Government policies around strong, resilient and supportive communities? What role do social workers adopt in community development and engagement in other countries and how is this supported by their education and training
Strategies for producing biochars with minimum PAH contamination
With the aim to develop initial recommendations for production of biochars with minimal contamination with polycyclic aromatic hydrocarbons (PAHs), we analysed a systematic set of 46 biochars produced under highly controlled pyrolysis conditions. The effects of the highest treatment temperature (HTT), residence time, carrier gas flow and typical feedstocks (wheat / oilseed rape straw pellets (WSP), softwood pellets (SWP)) on 16 US EPA PAH concentration in biochar were investigated. Overall, the PAH concentrations ranged between 1.2 and 100 mg kg-1. On average, straw-derived biochar contained 5.8 times higher PAH concentrations than softwood-derived biochar. In a batch pyrolysis reactor, increasing carrier gas flow significantly decreased PAH concentrations in biochar; in case of straw, the concentrations dropped from 43.1 mg kg-1 in the absence of carrier gas to 3.5 mg kg-1 with a carrier gas flow of 0.67 L min-1; for woody biomass PAHs concentrations declined from 7.4 mg kg-1 to 1.5 mg kg-1 with the same change of carrier gas flow. In the temperature range of 350-650°C the HTT did not have any significant effect on PAH content in biochars, irrespective of feedstock type, however, in biochars produced at 750°C the PAH concentrations were significantly higher. After detailed investigation it was deduced that this intensification in PAH contamination at high temperatures was most likely down to the specifics of the unit design of the continuous pyrolysis reactor used. Overall, it was concluded that besides PAH formation, vaporisation is determining the PAH concentration in biochar. The fact that both of these mechanisms intensify with pyrolysis temperature (one increasing and the other one decreasing the PAH concentration in biochar) could explain why no consistent trend in PAH content in biochar with temperature has been found in the literature
Synthesis and catalytic properties of highly branched palladium nanostructures using seeded growth
In order to develop nanocatalysts with enhanced catalytic performance, it is important to be able to synthesize nanocrystals enclosed by high-index surface facets, due to their high density of low coordinated atoms at step, ledge and kink sites. Here, we report a facile seed-mediated route to the synthesis of highly branched Pd nanostructures with a combination of {113}, {115} and {220} high-index surface planes. The size of these nanostructures is readily controlled by a simple manipulation of the seed concentration. The selective use of oleylamine and oleic acid was also found to be critical to the synthesis of these structures, with Pd icosahedra enclosed by low-index {111} facets being produced when hexadecylamine was employed as capping ligand. The structure–property relationship of these nanostructures as catalysts in Suzuki-cross coupling reactions was then investigated and compared, with the high-index faceted branched Pd nanostructures found to be the most effective catalysts
Does maternal influenza cause schizophrenia? : a Northwestern Ontario study / by Gillian Elizabeth Graham.
Accumulation of Sellafield-derived radiocarbon (14C) in Irish Sea and West of Scotland intertidal shells and sediments
The nuclear energy industry produces radioactive waste at various stages of the fuel cycle. In
the United Kingdom, spent fuel is reprocessed at the Sellafield facility in Cumbria on the
north west coast of England. Waste generated at the site comprises a wide range of
radionuclides including radiocarbon (14C) which is disposed of in various forms including
highly soluble inorganic carbon within the low level liquid radioactive effluent, via pipelines
into the Irish Sea. This 14C is rapidly incorporated into the dissolved inorganic carbon (DIC)
reservoir and marine calcifying organisms, e.g. molluscs, readily utilise DIC for shell
formation. This study investigated a number of sites located in Irish Sea and West of Scotland
intertidal zones. Results indicate 14C enrichment above ambient background levels in shell
material at least as far as Port Appin, 265 km north of Sellafield. Of the commonly found
species (blue mussel (Mytilus edulis), common cockle (Cerastoderma edule) and common
periwinkle (Littorina littorea)), mussels were found to be the most highly enriched in 14C due
to the surface environment they inhabit and their feeding behaviour. Whole mussel shell
activities appear to have been decreasing in response to reduced discharge activities since the
early 2000s but in contrast, there is evidence of continuing enrichment of the carbonate
sediment component due to in-situ shell erosion, as well as indications of particle transport of
fine 14C-enriched material close to Sellafield
Improving young people’s health and wellbeing through a school health research network: reflections on school-researcher engagement at the national level
The School Health Research Network is a policy-practice-research partnership established in Wales in 2013. The Network aims to: provide health and wellbeing data for national, regional and local stakeholders, including schools; co-produce school-based health improvement research for Wales; and build capacity for evidence-informed practice in the school health community. School-focused engagement activities include providing member schools with bespoke Student Health and Wellbeing Reports, hosting school health webinars, producing school-friendly research briefings, and holding annual events for schools. The Network’s model for co-producing research with schools is described and its impacts on schools is explored. These include more efficient recruitment of schools to research projects, school involvement in intervention development, schools beginning to embed evidence-informed practice by using their Reports and other Network resources, and securing funding to evaluate innovative health and wellbeing practices identified by schools. Drawing on the Trans-disciplinary Action Research (TDAR) literature, the article reflects on how TDAR principles have underpinned Network progress. The concept of reciprocity in the co-production literature and its relevance to engagement with schools is also explored, along with the Network’s contribution to our understanding of how we can build sustainable co-production at large scale in order to generate national level action and benefit
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