998 resultados para hyper-Dk material
Resumo:
This paper aims to contribute to the ongoing debate on the use of resource accounting tools in regional policy making. The Northern Limits project applied Material Flow Analysis and Ecological Footprinting to regional policy making in Northern Ireland over a number of years. The early phase of the research informed the regions first sustainable development strategy which was published in 2006 with key targets relating to the Ecological Footprint and improving the resource efficiency of the economy. Phase II identified the next steps required to address data availability and quality and the use of MFA and EF in providing a measurement and monitoring framework for the strategy and in the development of the strategy implementation plan. The use of MFA and Ecological Footprinting in sustainable regional policy making and the monitoring of its implementation is an ongoing process which has raised a number of research issues which can inform the ongoing application and development of these and other resource accounting tools to within Northern Ireland, provide insights for their use in other regions and help set out the priorities for research to support this important policy area.
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Chemoenzymatic dynamic kinetic resolution (DKR) of rac-1-phenyl ethanol into R-1-phenylethanol acetate was investigated with emphasis on the minimization of side reactions. The organometallic hydrogen transfer (racemization) catalyst was varied, and this was observed to alter the rate and extent of oxidation of the alcohol to form ketone side products. The performance of highly active catalyst [(pentamethylcyclopentadienyl) IrCl2(1-benzyl,3-methyl-imidazol-2-ylidene)] was found to depend on the batch of lipase B used. The interaction between the bio- and chemo-catalysts was reduced by employing physical entrapment of the enzyme in silica using a sol-gel process. The nature of the gelation method was found to be important, with an alkaline method preferred, as an acidic method was found to initiate a further side reaction, the acid catalyzed dehydration of the secondary alcohol. The acidic gel was found to be a heterogeneous solid acid.
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In this article, we take advantage of the recent availability of data from the special module on material deprivation in the 2009 European Union Statistics on Income and Living Conditions to develop a more comprehensive understanding of the relationship between material deprivation and economic stress, the mediating and moderating roles played by cross-national differences in levels of income and income inequality, and the implications for competing perspectives on the nature of reference groups in Europe. The article establishes the critical role of basic deprivation, relating to inability to enjoy customary standards of living, in influencing economic stress levels. National income levels and inequality had no direct influence on economic stress. However, the impact of basic deprivation was stronger in countries with higher levels of income, indicating the crucial role of national reference groups. An interaction between basic deprivation and income inequality was also observed. However, contrary to the expectation that experiencing basic deprivation in a national context of high income inequality is likely to be particularly stressful, the consequences of such deprivation were most negative in low inequality countries. Experiencing basic deprivation where high income levels and lower inequality would lead to the expectation that such deprivation is eminently avoidable exacerbates its impact. © The Author 2013.
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In this paper we consider the consequences for measurement of material deprivation, consistent poverty and economic vulnerability of the shift from the ECHP data set to the EU-SILC instrument. Despite the restricted number of deprivation items available in EU-SILC, we show that there is a substantial overlap between such measures when they are estimated using EU-wide and a set of Irish specific indicators. By placing the EU-wide measures in the context of the full range of Irish indicators, we demonstrate that they allow us to identify clusters of individuals sharply differentiated in terms of their multidimensional deprivation profiles. They also provide an understanding of the socio-economic factors associated with such differentiation that departs in only modest respects from that derived from the more comprehensive set of Irish specific indicators.
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In this article we use the first full wave of the Irish component of the EU Statistics on Income and Living Conditions survey to evaluate conflicting interpretations of levels and patterns of material deprivation in Ireland after the 'Celtic Tiger'. Radical critics of Irish economic policies have seen the Irish case as a particularly good illustration of the tendency for globalization to be accompanied by widespread economic vulnerability and marginalization. Here, employing a multidimensional perspective we identify one fifth of the population as being economically vulnerable and one in 14 as vulnerable to maximal deprivation, in that they exhibit high risks of deprivation across a range of life-style deprivation dimensions. Current levels and depth of material deprivation are a good deal more modest than suggested by radical critics of the Irish experience of economic globalization.
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Objectives: A healthy lifestyle may help maintain cognitive function and reduce the risk of developing dementia. This study employed a focus group approach in order to gain insight into opinions of mild cognitive impairment (MCI) patients, caregivers (CG) and health professionals (HP) regarding lifestyle and its relationship with cognition. The qualitative data were used to design, develop and pilot test educational material (EM) to help encourage lifestyle behaviour change. Method: Data gathering phase: structured interviews were conducted with HP (n = 10), and focus groups with MCI patients (n = 24) and CG (n = 12). EM was developed and pilot tested with a new group of MCI patients (n = 21) and CG (n = 6). Results: HP alluded to the lack of clinical trial evidence for a lifestyle and MCI risk link. Although they felt that lifestyle modifications should be recommended to MCI patients, they appeared hesitant in communicating this information and discussions were often patient-driven. MCI patients lacked awareness of the lifestyle cognition link. Participants preferred EM to be concise, eye-catching and in written format, with personal delivery of information favoured. Most pilot testers approved of the EM but were heterogeneous in terms of lifestyle, willingness to change and support needed to change. Conclusion: MCI patients need to be made more aware of the importance of lifestyle for cognition. EM such as those developed here, which are specifically tailored for this population would be valuable for HP who, currently, appear reticent in initiating lifestyle-related discussions. Following further evaluation, the EM could be used in health promotion activities targeting MCI patients.
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A key tracer of the elusive progenitor systems of Type Ia supernovae (SNe Ia) is the detection of narrow blueshifted time-varying Na I D absorption lines, interpreted as evidence of circumstellar material surrounding the progenitor system. The origin of this material is controversial, but the simplest explanation is that it results from previous mass-loss in a system containing a white dwarf and a non-degenerate companion star. We present new single-epoch intermediate-resolution spectra of 17 low-redshift SNe Ia taken with XShooter on the European Southern Observatory Very Large Telescope. Combining this sample with events from the literature, we confirm an excess (∼20 per cent) of SNe Ia displaying blueshifted narrow Na I D absorption features compared to redshifted Na I D features. The host galaxies of SNe Ia displaying blueshifted absorption profiles are skewed towards later-type galaxies, compared to SNe Ia that show no Na I D absorption and SNe Ia displaying blueshifted narrow Na I D absorption features have broader light curves. The strength of the Na I D absorption is stronger in SNe Ia displaying blueshifted Na I D absorption features than those without blueshifted features, and the strength of the blueshifted Na I D is correlated with the B − V colour of the SN at maximum light. This strongly suggests the absorbing material is local to the SN. In the context of the progenitor systems of SNe Ia, we discuss the significance of these findings and other recent observational evidence on the nature of SN Ia progenitors. We present a summary that suggests that there are at least two distinct populations of normal, cosmologically useful SNe Ia.
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Studies of urban metabolism provide important insights for environmental management of cities, but are not widely used in planning practice due to a mismatch of data scale and coverage. This paper introduces the Spatial Allocation of Material Flow Analysis (SAMFA) model as a potential decision support tool aimed as a contribution to overcome some of these difficulties and describes its pilot use at the county level in the Republic of Ireland. The results suggest that SAMFA is capable of identifying hotspots of higher material and energy use to support targeted planning initiatives, while its ability to visualise different policy scenarios supports more effective multi-stakeholder engagement. The paper evaluates this pilot use and sets out how this model can act as an analytical platform for the industrial ecology–spatial planning nexus.
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Uniform submicron La2NiO4+δ (sm-LNO) powders have been synthesized by a facile polyvinylpyrrolidone (PVP)-assisted hydrothermal route. In the presence of PVP, sm-LNO of pure phase has been obtained by calcination at the relatively low temperature of 900 °C for 8 h. Compared micron-sized LNO (m-LNO) particles obtained at 1,000 °C by hydrothermal synthesis route without PVP assisted, the sm-LNO-PVP displays regularly shaped and well-distributed particles in the range of 0.3–0.5 μm. The scanning electron microscopy (SEM) results showed that the sm-LNO sample is submicronic and that the m-LNO sample shows agglomerates with a broad size distribution. The electrochemical performance of m-LNO and sm-LNO-PVP has been investigated by electrochemical impedance spectroscopy. The polarization resistance of the sm-LNO-PVP cathode reaches a value of 0.40 Ω cm2 at 750 °C, which is lower than that of m-LNO (0.62 Ω cm2). This result indicates that a fine electrode microstructure with submicron particles can help to increase the active sites, accelerate oxygen diffusion, and reduce polarization resistance. An anode-supported single cell with sm-LNO cathode has been fabricated and tested over a temperature range from 650 to 800 °C. The maximum power density of the cell has achieved 834 mW cm−2 at 750 °C. These results therefore show that this PVP-assisted hydrothermal method is an effective approach to construct submicron-structured cathode and enhance the performance of intermediate temperature solid oxide fuel cell.
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We describe a simple strategy, which is based on the idea of space confinement, for the synthesis of carbon coating on LiFePO4 nanoparticles/graphene nanosheets composites in a water-in-oil emulsion system. The prepared composite displayed high performance as a cathode material for lithium-ion battery, such as high reversible lithium storage capacity (158 mA h g-1 after 100 cycles), high coulombic efficiency (over 97%), excellent cycling stability and high rate capability (as high as 83 mA h g -1 at 60 C). Very significantly, the preparation method employed can be easily adapted and be extended as a general approach to sophisticated compositions and structures for the preparation of highly dispersed nanosized structure on graphene.
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Interaction of organic xenobiotics with soil water-soluble humic material (WSHM) may influence their environmental fate and bioavailability. We utilized bacterial assays (lux-based toxicity and mineralization by Burkholderia sp. RASC) to assess temporal changes in the bioavailability of [14C]-2,4-dichlorophenol (2,4-DCP) in soil water extracts (29.5 μg mL-1 2,4-DCP; 840.2 μg mL-1 organic carbon). HPLC determined and bioavailable concentrations were compared. Gel permeation chromatography (GPC) was used to confirm the association of a fraction (>50%) of [14C]-2,4-DCP with WSHM. Subtle differences in parameters describing 2,4-DCP mineralization curves were recorded for different soil-2,4-DCP contact times. Problems regarding the interpretation of mineralization data when assessing the bioavailability of toxic compounds are discussed. The lux-bioassay revealed a time-dependent reduction in 2,4-DCP bioavailability: after 7 d, less than 20% was bioavailable. However, GPC showed no quantitative difference in the amount of WSHM-associated 2,4-DCP over this time. These data suggest qualitative changes in the nature of the 2,4-DCP-WSHM association and that associated 2,4-DCP may exert a toxic effect. Although GPC distinguished between free- and WSHM-associated 2,4-DCP, it did not resolve the temporal shift in bioavailability revealed by the lux biosensor. These results stress that assessment of risk posed by chemicals must be considered using appropriate biological assays.
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What does material culture tell us about gendered identities and how does gender reveal the meaning of spaces and things?
If we look at the objects that we own, covet and which surround us in our everyday culture, there is a clear connection between ideas about gender and the material world. This book explores the material culture of the past to shed light on historical experiences and identities. Some essays focus on specific objects, such as an eighteenth-century jug or a twentieth-century powder puff, others on broader material environments, such as the sixteenth-century guild or the interior of a twentieth-century pub, while still others focus on the paraphernalia associated with certain actions, such as letter-writing or maintaining eighteenth-century men's hair.
Written by scholars in a range of history-related disciplines, the essays in this book offer exposés of current research methods and interests. These demonstrate to students how a relationship between material culture and gender is being addressed, while also revealing a variety of intellectual approaches and topics.
Resumo:
Abstract The material flow in friction stir spot welding of aluminium to both aluminium and steel has been investigated, using pinless tools in a lap joint geometry. The flow behaviour was revealed experimentally using dissimilar Al alloys of similar strength. The effect on the material flow of tool surface features, welding conditions (rotation speed, plunge depth, dwell time), and the surface state of the steel sheet (un-coated or galvanized) have been systematically studied. A novel kinematic flow model is presented, which successfully predicts the observed layering of the dissimilar Al alloys under a range of conditions. The model and the experimental observations provide a consistent interpretation of the stick-slip conditions at the tool-workpiece interface, addressing an elusive and long-standing issue in the modelling of heat generation in friction stir processing.
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The objective of this research was to design granulated iron oxide for the adsorption of heavy metals from wastewater. Polyvinyl acetate (PVAc) was chosen as a suitable binder; as it is water insoluble. Initial experiments on selection of suitable solvent of the polymer were carried out using three solvents namely; methanol, acetone and toluene. Based on the initial tests on product yield and mechanical strength, acetone was selected as the solvent for the polyvinyl acetate binder. Design of experiment was then used to investigate the influence of granulation process variables; impeller speed, binder concentration and liquid to solid ratio on the properties of the granular materials. The response variables in the study were granules mean size, stability in water and granule strength. The results showed that the combination of high impeller speed and high binder concentration favour the formation of strong and stable granules. Results also showed that leaching of the binder into the simulated was water was negligible. Trial adsorption experiments carried out using the strongest and most stable iron oxide granules produced in this work showed removal efficiency of around 70% of synthetic arsenic solutions with initial concentration of 1000 ppb.