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1.
Incineration has suffered from a sustained campaign of misinformation. Consequently it has been regarded as the least sustainable option for the treatment of wastes, including sewage sludge. By looking carefully at the issues surrounding the incineration of sewage sludge, as an example, it can be seen that reality does not support the commonly held view. Modern plants are an effective means of recovering the energy value of sludge and at the same time offer a continuous operation, which is independent of weather or land constraints.
Of course incineration needs to be regulated and EU Directives and National Regulations set the emission standards. The technology is such that these standards can be met, and more than this, the systems are capable of upgrading as more stringent standards are imposed.
Concerns over NOx, dioxins, metals and pathogens are highlighted. In addition the permitting process is discussed. None of these should present a barrier to the implementation of incineration projects. Indeed the paper goes further and demonstrates that there is likely to be an increasing role for incineration as landfill, recycling to agricultural land and other options become more restrictive.  相似文献   
2.
River water has been sampled under baseflow conditions in both summer and winter at c. 250-m intervals along the length of each of seven rivers in northeast Scotland, and the nitrate contents have been determined. The resultant data have been examined in the context of the nitrogen saturation hypothesis. Capacity of the catchment soils to retain nitrate was generally minimal in winter. Although biological uptake of nitrate was evident in summer, in the upper part of each catchment substantial nitrate leaching still occurred. The phenomenon was most marked in water draining from hill peats, except where these were conspicuously waterlogged. The results are discussed in the context of possible nitrogen saturation effects on upper catchment slopes.  相似文献   
3.
Facebook and other social media have been hailed as delivering the promise of new, socially engaged educational experiences for students in undergraduate, self‐directed, and other educational sectors. A theoretical and historical analysis of these media in the light of earlier media transformations, however, helps to situate and qualify this promise. Specifically, the analysis of dominant social media presented here questions whether social media platforms satisfy a crucial component of learning – fostering the capacity for debate and disagreement. By using the analytical frame of media theorist Raymond Williams, with its emphasis on the influence of advertising in the content and form of television, we weigh the conditions of dominant social networking sites as constraints for debate and therefore learning. Accordingly, we propose an update to Williams' erudite work that is in keeping with our findings. Williams' critique focuses on the structural characteristics of sequence, rhythm, and flow of television as a cultural form. Our critique proposes the terms information design, architecture, and above all algorithm, as structural characteristics that similarly apply to the related but contemporary cultural form of social networking services. Illustrating the ongoing salience of media theory and history for research in e‐learning, the article updates Williams' work while leveraging it in a critical discussion of the suitability of commercial social media for education.  相似文献   
4.
Government agencies use information technology extensively to collect business data for regulatory purposes. Data communication standards form part of the infrastructure with which businesses must conform to survive. We examine the development of, and emerging competition between, two open business reporting data standards adopted by government bodies in France; Electronic Data Interchange for Administration, Commerce and Transport (EDIFACT) (incumbent) and eXtensible Business Reporting Language (XBRL) (challenger). The research explores whether an incumbent may be displaced in a setting in which the contest is unresolved. Latour's translation map is applied to trace the enrollments and detours in the battle. We find that regulators play an important role as allies in the development of the standards. The antecedent networks in which the standards are located embed strong beliefs that become barriers to collaboration and fuel the battle. One of the key differentiating attitudes is whether speed is more important than legitimacy. The failure of collaboration encourages competition. The newness of XBRL's technology just as regulators need to respond to an economic crisis and its adoption by French regulators not using EDIFACT create an opportunity for the challenger to make significant network gains over the longer term. ANT also highlights the importance of the preservation of key components of EDIFACT in ebXML.  相似文献   
5.
6.
The implementation of synthetic guided wave focusing to locate axially aligned defects in pipes has been investigated. Results from both finite element computer models and experiments on real pipes are presented and the data show good agreement. Focusing is necessary to improve the reflection coefficient from axially aligned defects, as the signals are very weak. The Common Source Method (CSM) of synthetic focusing has been applied which makes it possible to apply focusing via post processing to previously collected data. The dependence of reflection coefficient on crack length was measured for both through thickness and part depth axially aligned defects, at a range of frequencies, using the torsional guided wave family. The results show that the reflection coefficient is approximately doubled when focusing is employed, compared to the sensitivity for unfocused fundamental torsional waves. However the sensitivity is still very low, so in practise this approach could only be used to find severe defects.  相似文献   
7.
Understanding the process of domestic retrofit is important for learning and innovation. This is particularly the case for low carbon retrofits such as those undertaken under the UK's Retrofit for the Future (RftF) programme, with its aim to achieve an overall 80% carbon reduction by 2050. Current post-occupancy evaluation (POE) research has both theoretical and methodological limitations with implications for technical and behavioural research in the built environment. Drawing on relevant ideas and concepts from social practice theory and science and technology studies, principally prefiguration (constraints/enablement), black-boxing, heating and cooling practices, this paper demonstrates how the relationship between buildings and people could be reconceptualized as mutually constitutive and co-evolving through a process of ‘interactive adaptation’. The concept of ‘interactive adaptation’ is explored through a novel approach to integrating physical and social data collected from a sample of dwellings selected from the RftF programme. Analysis yields insights into the influences and pathways of interactive adaptation resulting from retrofit technology and practices. The implications of these insights for policy-makers, the research community and practitioners are discussed: end-use energy demand policy needs to be informed by a socio-technical approach.  相似文献   
8.
The Cr3C2?C peritectic fixed point was investigated to test its capability to serve as a practical high-temperature fixed point. An improved filling technique where C/C sheet works as a wick and graphite paper as a hopper was applied successfully, and the long-term stability of the peritectic cell was evaluated by means of radiation thermometry. The repeatability of the melting point in one day was 7 mK with a melting range of approximately 100 mK. The cell was aged for 7 days, and the evaluated 56 melting temperatures during this period all fall within 90 mK, with a standard deviation of 19 mK. X-ray transmission photos showed that the ingot was filled uniformly in the crucible. After the evaluation of long-term stability, no clear degradation of the ingot shape and no leakage of molten metal were observed. From these results, it can be concluded that the Cr3C2?C peritectic cell has good stability and robustness, and the new filling technique was established. The impurity effect on the Cr3C2?C peritectic cell was also investigated by adding tungsten powder to another cell as the impurity component. After the observation of melting and freezing plateaux, the cell was cut in half to analyze the microstructure by means of electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS). The high concentration of impurity was observed in the area of the chromium-rich domain (eutectic mixture of Cr7C3 and Cr3C2), which suggests that impurities were rejected from the Cr3C2 peritectic phase during the peritectic freezing and were accumulated in the Cr7C3?Cr3C2 eutectic phase. This explains why the impurity effect is more severe for the Cr7C3?Cr3C2 eutectic point than for the Cr3C2?C peritectic point.  相似文献   
9.
Thermocouples can be calibrated at pure metal ingot-based fixed points at temperatures up to the freezing point of copper (1084.62 °C). For Pt/Pd thermocouples, the deviation from the accepted reference function very often takes an approximately linear form up to the copper fixed point. The calibration of Pt/Pd thermocouples may therefore be more amenable to extrapolation than that of Pt/Pt-Rh thermocouples. Here, the melting temperatures of a Co?CC and a Pd?CC eutectic fixed point are determined by extrapolating the deviation functions of several Pt/Pd thermocouples, after the fashion of Edler et al. The results are compared with the melting temperatures measured using non-contact radiation thermometry. The expanded uncertainty (k = 2) of the melting temperatures determined by extrapolation of the Pt/Pd thermocouple calibrations is ±0.32 °C for the Co?CC fixed point, and ±0.49 °C for the Pd?CC fixed point. For both fixed points, these uncertainties are comparable to those of non-contact radiation thermometry measurements. While a number of assumptions are made in performing the extrapolation of the calibrations, the method does appear to offer a useful complement to non-contact radiation thermometry measurements.  相似文献   
10.
Little detailed evidence has previously been available regarding the uptake rate or prevalence of energy efficiency interventions among specific household groups. This study uses the Home Energy Efficiency Database (HEED) to investigate both the combination of measures that have been installed, and in which dwellings, according to key neighbourhood socio-demographic variables, including income and tenure. Analysis of 2000–07 data indicates that approximately 40% (9.3 million) dwellings in England had approximately 23.7 million efficiency measures installed, with an average of 2.5 measures per dwelling. Building fabric-related measures were the most frequent (e.g. cavity wall insulation, loft insulation and glazing) with an average of 2.1 million installed each year. Dwellings with the highest number of fabric interventions (the top 20%) were more likely to be found in areas with low income, with more owner-occupied dwellings, experiencing lower winter temperatures, having a lower proportion of flats, and having a slightly higher proportion of older adults and children. Energy efficiency installations have tended to occur among specific types of households or parts of the building stock. These findings have implications for the design of future government programmes for targeting energy efficiency measures to specific household groups or dwelling types.  相似文献   
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