20 resultados para Spillover
em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast
Resumo:
The effect of spillover processes on the activity of a catalyst system consisting of a mixed oxygen ion and electronic conducting support La0.6Sr0.4Co0.2Fe0.8O3d and a metal catalyst (Pt) were investigated. Two types of model single-pellet catalysts were used employing Pt deposited on both sides of a dense LSCF disc pellet. One of these single pellets employed highly disperse, physically non-continuous Pt, in contrast to studies on electrochemical promotion, while the other used a low dispersion continuous film. Driving forces for promoter migration were controlled through the manipulation of the oxygen chemical potential difference across the membrane. Catalyst rate modification was observed in all cases. However, it was found that there is a complex relationship between the rate modification, the driving forces for spillover and the geometrical arrangement of the catalyst on the support (i.e. catalyst dispersion).
Resumo:
Environmental friendly renewable energy plays an indispensable role in energy industry development. Foreign direct investment (FDI) in advanced renewable energy technology spillover is promising to improve technological capability and promote China’s energy industry performance growth. In this paper, the impacts of FDI renewable energy technology spillover on China’s energy industry performance are analyzed based on theoretical and empirical studies. Firstly, three hypotheses are proposed to illustrate the relationships between FDI renewable energy technology spillover and three energy industry performances including economic, environmental, and innovative performances. To verify the hypotheses, techniques including factor analysis and data envelopment analysis (DEA) are employed to quantify the FDI renewable energy technology spillover and the energy industry performance of China, respectively. Furthermore, a panel data regression model is proposed to measure the impacts of FDI renewable energy technology spillover on China’s energy industry performance. Finally, energy industries of 30 different provinces in China based on the yearbook data from 2005 to 2011 are comparatively analyzed for evaluating the impacts through the empirical research. The results demonstrate that FDI renewable energy technology spillover has positive impacts on China’s energy industry performance. It can also be found that the technology spillover effects are more obvious in economic and technological developed regions. Finally, four suggestions are provided to enhance energy industry performance and promote renewable energy technology spillover in China.
Resumo:
Purpose – This paper aims to examine the antecedent influences and merits of workplace occupations as a tactical response to employer redundancy initiatives.
Design/methodology/approach – The data are based on analysis of secondary documentary material reporting on three workplace occupations in the Republic of Ireland during 2009.
Findings – Perceptions of both procedural (e.g. employer unilateral action) and substantive (e.g. pay and entitlements) justice appear pivotal influences. Spillover effects from other known occupations may also be influential. Workplace occupations were found to produce some modest substantive gains, such as enhancing redundancy payments. The tactic of workplace occupation was also found to transform unilateral employer action into scenarios based upon negotiated settlement supported by third-party mediation. However the tactic of workplace occupation in response to redundancy runs the risks of potential judicial injunction and sanction.
Research limitations/implications – Although operationally difficult, future studies should strive to collect primary data workplace occupations as they occur.
Originality/value – The paper identifies conditions conducive to the genesis of workplace occupations and the extent to which the tactic may be of benefit in particular circumstances to workers facing redundancy. It also contextualises the tactic in relation to both collective mobilisation and bargaining theories in employment relations.
Resumo:
This study examined the previously unexplored occupational grade-specific relationships of domestic responsibilities, the age of children, and work-family spillover, with registered sickness absence (>3 days' sick leave episodes, a mean follow-up of 17 months; n = 18,366 municipal employees; 76% women). The results showed that negative spillover from work into family life predicted a heightened rate of sickness absence spells among both women and men in all occupational categories (except upper white-collar men), but especially among blue-collar and lower white-collar employees. Furthermore, among all white-collar employees (except upper white-collar men), having young children (
Resumo:
The selective hydrogenation of ,-unsaturated aldehydes and ketones has been studied using ketoisophorone and cinnamaldehyde as model substrates using manganese oxide octahedral molecular sieve (OMS-2) based catalysts. For the first time, OMS-2 has been shown to be an efficient and selective hydrogenation catalyst. High selectivities for either the CC or CO double bond at approximate to 100% conversion were achieved by using OMS-2 and platinum supported on OMS-2 catalysts. Density functional theory (DFT) calculations showed that the dissociation of H2 on OMS-2 was water assisted and occurred on the surface Mn of OMS-2(001) that had been modified by an adsorbed H2O molecule. The theoretically calculated activation barrier was in good agreement with the experimentally determined value for the hydrogenation reactions, indicating that H2 dissociation on OMS-2 is likely to be the rate-determining step. A significant increase in the rate of reaction was observed in the presence of Pt as a result of the enhancement of H2 dissociative adsorption and subsequent reaction on the Pt or spillover of the hydrogen to the OMS-2 support. The relative adsorption strengths of ketoisophorone and cinnamaldehyde on the OMS-2 support compared with the Pt were found to determine the product selectivity.
Resumo:
By depositing ceria over supported precious metal (PM) catalysts and characterizing them with in situ diffuse reflectance UV (DR UV) and in situ Raman spectroscopy, we have been able to prove a direct correlation between a decrease in ceria band gap and the work function of the metal under reducing conditions. The PM ceria interaction results in changes on the ceria side of the metal ceria interface, such that the degree of oxygen vacancy formation on the ceria surface also correlates with the precious metal work function. Nevertheless, conclusive evidence for a purely electronic interaction could not be provided by X-ray photoelectron spectroscopy (XPS) analysis. On the contrary, the results highlight the complexity of the PM ceria interaction by supporting a spillover mechanism resulting from the electronic interaction under reducing conditions. Under oxidizing conditions, another effect has been observed; namely, a structural modification of ceria induced by the presence of PM cations. In particular, we have been able to demonstrate by in situ Raman spectroscopy that, depending on the PM ionic radius, it is possible to create PM ceria solid solutions. We observed that this structural modification prevails under an oxidizing atmosphere, whereas electronic and chemical interactions take place under reducing conditions.
Resumo:
Unfavorable work characteristics, such as low job control and too high or too low job demands, have been suggested to increase the likelihood of physical inactivity during leisure time, but this has not been verified in large-scale studies. The authors combined individual-level data from 14 European cohort studies (baseline years from 19851988 to 20062008) to examine the association between unfavorable work characteristics and leisure-time physical inactivity in a total of 170,162 employees (50 women; mean age, 43.5 years). Of these employees, 56,735 were reexamined after 29 years. In cross-sectional analyses, the odds for physical inactivity were 26 higher (odds ratio 1.26, 95 confidence interval: 1.15, 1.38) for employees with high-strain jobs (low control/high demands) and 21 higher (odds ratio 1.21, 95 confidence interval: 1.11, 1.31) for those with passive jobs (low control/low demands) compared with employees in low-strain jobs (high control/low demands). In prospective analyses restricted to physically active participants, the odds of becoming physically inactive during follow-up were 21 and 20 higher for those with high-strain (odds ratio 1.21, 95 confidence interval: 1.11, 1.32) and passive (odds ratio 1.20, 95 confidence interval: 1.11, 1.30) jobs at baseline. These data suggest that unfavorable work characteristics may have a spillover effect on leisure-time physical activity.
Resumo:
Although widely debated in broader socioeconomic terms, the Eurozone crisis has not received adequate scholarly attention with regards to the impact of alternative political systems. This article revisits the debate on majoritarian and consensus democracies drawing on recent evidence from the Eurozone debacle. Greece is particularly interesting both with regards to its potential ‘global spillover effects’ and choice of political system. Despite facing comparable challenges as Portugal and Spain, the country has become polarized socially and politically, seeing a record number of MP defections, electoral volatility and the rise of the militant extreme right. The article explains why Greece, the country that relied most extensively on majoritarian institutions, entered the global financial crisis in the most vulnerable position while subsequently faced insurmountable political and institutional obstacles in its management. The article points to the paradox of majoritarianism: in times of economic stress, the first ‘casualties’ are its strongest elements – centrist parties (bi-partisanship) and cabinet stability.
Resumo:
The sustainability of cross-border peacebuilding initiatives is increasingly pertinent in a context of reduced public funding (national and European), yet the potential contribution to be made to this from private sector cooperation remains under-explored. This paper brings together quantitative data on cross-border trade with qualitative evidence from business leaders in the Irish border region in order to examine the nature of cross-border cooperation within the private sector and its possible connections to peacebuilding. This evidence is analysed in the light of three theses: spillover, contact and business-based peacebuilding. The first part of this paper assesses the conditions for cross-border business cooperation in Ireland, including funding support for economic development, European integration, and (post-Agreement) institutional change. The second part examines the particular contributions made by the private sector to peace, centring upon consciously non-political motivations (such as pragmatism and profit), networking and leadership.
Resumo:
Reactivity of supported gold catalysts is a hot topic in catalysis for many years. This communication reports an investigation on the dissociation of molecular hydrogen at the perimeter sites of Au/TiO2 and the spillover of hydrogen atoms from the gold to the support using density functional theory calculations. It is found that the heterolytic dissociation is favoured in comparison with homolytic dissociation of molecular hydrogen at the perimeter sites. However, the surface oxygen of the rutile TiO2(110) surface at these sites can be readily passivated by the formed OH, suggesting that further dissociation of molecular hydrogen may occur at pure gold sites.
A sting in the spit: widespread cross-infection of multiple RNA viruses across wild and managed bees
Resumo:
Declining populations of bee pollinators are a cause of concern, with major repercussions for biodiversity loss and food security. RNA viruses associated with honeybees represent a potential threat to other insect pollinators, but the extent of this threat is poorly understood. This study aims to attain a detailed understanding of the current and ongoing risk of emerging infectious disease (EID) transmission between managed and wild pollinator species across a wide range of RNA viruses. Within a structured large-scale national survey across 26 independent sites, we quantify the prevalence and pathogen loads of multiple RNA viruses in co-occurring managed honeybee (Apis mellifera) and wild bumblebee (Bombus spp.) populations. We then construct models that compare virus prevalence between wild and managed pollinators. Multiple RNA viruses associated with honeybees are widespread in sympatric wild bumblebee populations. Virus prevalence in honeybees is a significant predictor of virus prevalence in bumblebees, but we remain cautious in speculating over the principle direction of pathogen transmission. We demonstrate species-specific differences in prevalence, indicating significant variation in disease susceptibility or tolerance. Pathogen loads within individual bumblebees may be high and in the case of at least one RNA virus, prevalence is higher in wild bumblebees than in managed honeybee populations. Our findings indicate widespread transmission of RNA viruses between managed and wild bee pollinators, pointing to an interconnected network of potential disease pressures within and among pollinator species. In the context of the biodiversity crisis, our study emphasizes the importance of targeting a wide range of pathogens and defining host associations when considering potential drivers of population decline.