272 research outputs found
Introducing KiVa school-based antibullying programme to the UK: A preliminary examination of effectiveness and programme cost
This is the author accepted manuscript. The final version is available from Sage Publications via the DOI in this record.Bullying is an internationally recognized problem and school-based bullying is particularly pervasive. KiVa is a robustly evidenced school-based antibullying programme developed and evaluated at Turku University, Finland, and subsequently disseminated across Finland. Following a positive UK trial of Unit 2 (for 10- to 12-year-olds), further UK dissemination has taken place. This study presents (a) pupil self-reported levels of victimization and bullying prior to, and after, one year of KiVa implementation (Units 1 and 2) with 7- to 11-year-olds from 41 schools, and (b) programme training and delivery costs. Data from 41 primary schools were analysed using a linear mixed model effects analysis. Results revealed statistically significant reductions in victimization and bullying after one year of programme implementation. Ongoing costs were small, at Ā£2.84 per Key Stage 2 pupil per annum. These promising results highlight the need for further more rigorous evaluation of KiVa in the UK, including the exploration of factors associated with effective implementation, and the importance for educators and policy makers of evaluating both impact and costs when implementing programmes to prevent and reduce bullying.BIG Lottery Wales innovation fun
A Hydrodynamic Study of Benzyl Alcohol Oxidation in a Micro-Packed Bed Reactor
The various flow regimes prevalent during gold-palladium catalyzed benzyl alcohol oxidation in a
micro-packed bed reactor and their influence on reaction performance are identified. The reaction is studied
in a 300Ī¼m deep x 600Ī¼m wide silicon-glass micro-structured reactor packed with 65Ī¼m catalyst particles at
a temperature of 120Ā°C, pressure of 1 bar (g), using pure oxygen and neat benzyl alcohol as the feed.
Significant improvement in the conversion and selectivity to the main product, benzaldehyde, is observed
with increasing gas flowrate and decreasing liquid flowrate, which coincides with a change in the flow
pattern from āliquid-dominated slugā (segregated regions of liquid and gas slugs) to āgas-continuous trickleā
(thin film coated catalyst particles with gas flowing through the voids). The latter flow regime results in
enhanced external mass transfer due to an increase in the available interfacial area and shorter diffusional
distances. Results show selectivity up to 81% at a catalyst space time of 76 gcatgalc
-1.s, outperforming a
conventional batch laboratory reactor
Approaching Theoretical Performances of Electrocatalytic Hydrogen Peroxide Generation by Cobalt-Nitrogen Moieties
Electrocatalytic oxygen reduction reaction (ORR) has been intensively studied for environmentally benign applications. However, insufficient understanding of ORR 2 eā-pathway mechanism at the atomic level inhibits rational design of catalysts with both high activity and selectivity, causing concerns including catalyst degradation due to Fenton reaction or poor efficiency of H2O2 electrosynthesis. Herein we show that the generally accepted ORR electrocatalyst design based on a Sabatier volcano plot argument optimises activity but is unable to account for the 2 eā-pathway selectivity. Through electrochemical and operando spectroscopic studies on a series of CoNx/carbon nanotube hybrids, a construction-driven approach based on an extended ādynamic active site saturationā model that aims to create the maximum number of 2 eā ORR sites by directing the secondary ORR electron transfer towards the 2 eā intermediate is proven to be attainable by manipulating O2 hydrogenation kinetics
Sustainable production of glucaric acid from corn stover via glucose oxidation: An assessment of homogeneous and heterogeneous catalytic oxidation production routes
Glucaric acid is being used increasingly as a food additive, corrosion inhibitor, in deicing, and in detergents, and is also a potential starting material for the production of adipic acid, the key monomer for nylon-66. This work describes a techno-economic analysis of a potential bio-based process for the production of pure glucaric acid from corn stover (biomass). Two alternative routes for oxidation of glucose to glucaric acid are considered: via heterogeneous catalytic oxidation with air, and by homogeneous glucose oxidation using nitric acid. Techno-economic and lifecycle assessments (TEA, LCA) are made for both oxidation routes and cover the entire process from biomass to pure crystalline glucaric acid that can be used as a starting material for the production of valuable chemicals. This is the first TEA of pure glucaric acid production incorporating ion exchange and azeotropic evaporation below 50 Ā°C to avoid lactone formation. The developed process models were simulated in Aspen Plus V9. The techno-economic assessment shows that both production routes are economically viable leading to minimum selling prices of glucaric acid of ā¼2.91/kg for the heterogeneous catalytic route and the homogeneous glucose oxidation route respectively. It is shown that the heterogeneous catalytic oxidation route is capable of achieving a 22% lower environmental impact than the homogeneous glucose oxidation route. Opportunities for further improvement in sustainable glucaric acid production at industrial scale are identified and discussed
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Solvent inhibition in the liquid-phase catalytic oxidation of 1,4-butanediol: Understanding the catalyst behaviour from NMR relaxation time measurements
Solvent inhibition over surfaces affects behaviour and performances of heterogeneous catalysts.Johnson Matthey, EvonikDegussa, Technology Strategy Board (Grant ID: TP/7/ZEE/6/I/N0262B), Engineering and Physical Sciences Research Council and CASTech consortium (Grant ID: EP/G011397/1), Wolfson College Cambridg
The incredible years therapeutic dinosaur programme to build social and emotional competence in welsh primary schools: study protocol for a randomised controlled trial
<p>Abstract</p> <p>Background</p> <p>School interventions such as the Incredible Years <it>Classroom </it>Dinosaur Programme targets pupil behaviour across whole classrooms, yet for some children a more intense approach is needed. The Incredible Years <it>Therapeutic </it>Dinosaur Programme is effective for clinically referred children by enhancing social, problem-solving skills, and peer relationship-building skills when delivered in a clinical setting in small groups.</p> <p>The aim of this trial is to evaluate the effectiveness of the Therapeutic Programme, delivered with small groups of children at high-risk of developing conduct disorder, delivered in schools already implementing the Classroom Programme.</p> <p>Methods/Design</p> <p>This is a pragmatic, parallel, randomised controlled trial.</p> <p>Two hundred and forty children (aged 4-8 years) rated by their teacher as above the 'borderline cut-off' for concern on the Strengths and Difficulties Questionnaire, and their parents, will be recruited.</p> <p>Randomisation is by individual within blocks (schools); 1:1 ratio, intervention to waiting list control.</p> <p>Twenty schools will participate in two phases. Two teachers per school will deliver the programme to six intervention children for 2-hours/week for 18 weeks between baseline and first follow-up. The control children will receive the intervention after first follow up.</p> <p>Phase 1 comprises three data collection points - baseline and two follow-ups eight months apart. Phase 2 includes baseline and first follow-up.</p> <p>The Therapeutic Programme includes elements on; Learning school rules; understanding, identifying, and articulating feelings; problem solving; anger management; how to be friendly; how to do your best in school.</p> <p>Primary outcomes are; change in child social, emotional and behavioural difficulties. Secondary outcomes are; teacher and parent mental wellbeing, child academic attainment, child and teacher school attendance. Intervention delivery will be assessed for fidelity.</p> <p>Intention to treat analyses will be conducted. ANCOVA, effect sizes, mediator and moderator analyses will be applied to establish differences between conditions, and for whom the intervention works best for and why.</p> <p>Discussion</p> <p>This trial will provide information on the delivery and effectiveness of a child centred, school-based intervention delivered in small groups of children, at risk of developing more severe conduct problems. The effects on child behaviour in school and home environments, academic attainment, peer interactions, parent and teacher mental health will be assessed.</p> <p>Trial Registration</p> <p>UK Clinical Research Network UKCRNID8615</p> <p>Current Controlled Trials <a href="http://www.controlled-trials.com/ISRCTN96803379">ISRCTN96803379</a></p
Identification of single-site gold catalysis in acetylene hydrochlorination
There remains considerable debate over the active form of gold under operating conditions of a recently validated gold catalyst for acetylene hydrochlorination. We have performed an in situ x-ray absorption fine structure study of gold/carbon (Au/C) catalysts under acetylene hydrochlorination reaction conditions and show that highly active catalysts comprise single-site cationic Au entities whose activity correlates with the ratio of Au(I):Au(III) present. We demonstrate that these Au/C catalysts are supported analogs of single-site homogeneous Au catalysts and propose a mechanism, supported by computational modeling, based on a redox couple of Au(I)-Au(III) species
Impact of Nanoparticle-Support Interactions in CoāOā/AlāOā Catalysts for the Preferential Oxidation of Carbon Monoxide
Different supporting procedures were followed to alter the nanoparticle-support interactions (NPSI) in two Co3O4/Al2O3 catalysts, prepared using the reverse micelle technique. The catalysts were tested in the dry preferential oxidation of carbon monoxide (CO-PrOx) while their phase stability was monitored using four complementary in situ techniques, viz., magnet-based characterization, PXRD, and combined XAS/DRIFTS, as well as quasi in situ XPS, respectively. The catalyst with weak NPSI achieved higher CO2 yields and selectivities at temperatures below 225 Ā°C compared to the sample with strong NPSI. However, relatively high degrees of reduction of Co3O4 to metallic Co were reached between 250 and 350 Ā°C for the same catalyst. The presence of metallic Co led to the undesired formation of CH4, reaching a yield of over 90% above 300 Ā°C. The catalyst with strong NPSI formed very low amounts of metallic Co (less than 1%) and CH4 (yield of up to 20%) even at 350 Ā°C. When the temperature was decreased from 350 to 50 Ā°C under the reaction gas, both catalysts were slightly reoxidized and gradually regained their CO oxidation activity, while the formation of CH4 diminished. The present study shows a strong relationship between catalyst performance (i.e., activity and selectivity) and phase stability, both of which are affected by the strength of the NPSI. When using a metal oxide as the active CO-PrOx catalyst, it is important for it to have significant reduction resistance to avoid the formation of undesired products, e.g., CH4. However, the metal oxide should also be reducible (especially on the surface) to allow for a complete conversion of CO to CO2 via the Mars-van Krevelen mechanism
Three step synthesis of benzylacetone and 4-(4-methoxyphenyl)butan-2-one in flow using micropacked bed reactors
The synthesis of benzylacetone from benzyl alcohol and of 4-(4-methoxyphenyl)butan-2-one from 4-methoxybenzyl alcohol, which were previously performed in a batch cascade, were successfully performed in a telescoped flow system consisting of three micropacked bed reactors and a tube-in-tube membrane to remove oxygen. The system consisted of approximately 10 mg of 1 wt% AuPd/TiO2 catalyst for oxidation, 150ā250 mg of anatase TiO2 for CāC coupling and 10 mg of 1 wt% Pt/TiO2 for reduction, operating at 115 Ā°C, 130 Ā°C and 120 Ā°C respectively. Oxygen and hydrogen flowrates were 2 and 1.5 NmL/min and alcohol solution inlet flowrates were 10ā80 ĀµL/min, while the system operated at a back pressure of 5 barg. This system achieved significantly increased yields of benzylacetone compared to the batch cascade (56% compared to 8%) and slightly increased yields of 4-(4-methoxyphenyl)butan-2-one (48% compared to 41% when using the same catalyst supports). The major advantage of the telescoped flow system was the ability to separate the three reactions, so that each reaction could have its own catalyst and operating conditions, which led to significant process intensification
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