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111.
112.
Eva Sterner 《Construction Management & Economics》2013,31(1):21-30
The results of a survey show that both public and private building clients in Sweden, to varying extents, include environmental requirements in their procurement documents. The requirements identified have been classified into six categories primarily related to building and demolition waste, building material, contractors' environmental work, ecological aspects, construction work and other. One conclusion is that requirements regarding the separation of waste and a contractor's environmental policy are considered important, since they are stipulated in the majority of projects. Another finding is that requirements related to operation and especially to energy use are not considered sufficiently. Structured interviews were conducted with three of the clients who at that time of the survey had developed the most complete procurement documents with regard to environmental requirements. The aim of the interviews was to investigate how the stipulation of requirements, the evaluation of environmental aspects and the verification of environmental requirements were carried out. The conclusion drawn is that Swedish clients find the stipulation of requirements relatively uncomplicated, but find the evaluation of environmental impact, mainly related to selection of materials, problematic due to inadequate evaluation models. 相似文献
113.
Christiane Reis Fonseca José Luiz Paiva Eva Maria Rodriguez Fernando Juan Beltrán Antonio Carlos Silva Costa Teixeira 《臭氧:科学与工程》2017,39(4):255-263
The sugar industry is concerned with color formation due to the oxidation of phenolic compounds in the presence of carbohydrates. In this study, we investigated the ozonation of a mixture of five phenolic compounds in water and aqueous sucrose solution: p-coumaric (p-COU), caffeic (CAF), syringic (SYR), and chlorogenic (CHO) acids, as well as the flavonoid quercetin (QUE). The experiments were carried out in a 3-L glass reactor with magnetic stirring and a diffuser plate at the bottom to feed the ozone-oxygen gas mixture. Initial solution concentrations of 5 mg L?1 of each acid, 15 mg L?1 of quercetin, and 40 g L?1 of sucrose were used. The degradation of phenolic compounds followed apparent first-order kinetics, with rate constants and percent removals decreasing in the presence of sucrose. In water, average consumed ozone dosages of 10.4 and 18.7 mg L?1 were necessary for 50% and 90% removals, respectively, for CHO, CAF, and p-COU; for QUE they were slightly higher (13.9 and 20.5 mg L?1, respectively). At a consumed dosage of 20.8 mg O3 L?1, more than 99% removal was obtained for CHO, CAF, and p-COU, while 96.2% was achieved for SYR. In contrast, QUE revealed to be more recalcitrant during ozonation in the absence of sucrose, with only 70% removal at the highest consumed O3 dosage. The consumed ozone dosages for 50% and 90% removals were higher for CHO, CAF, and p-COU in aqueous sucrose solution, which may impact ozone consumption during real sugarcane juice treatment. Sucrose and t-butanol were the main influential parameters that significantly affected the total amount of phenolic compounds degraded. 相似文献
114.
The nanostructure and dewetting of block copolymer thin films annealed in different neutral solvents
Eva Oktavia Ningrum Wei‐Ting Lin Chieh‐Tsung Lo 《Polymer Engineering and Science》2011,51(7):1339-1346
The morphology of polystyrene‐b‐poly(2‐vinyl pyridine) thin films annealed under various neutral solvents was investigated. The morphological transition depends on the vapor pressure of the solvent, the quantity of the solvent in the film, and annealing time. We introduced the volume fraction of solvent in a film (Q) to correlate these factors to the morphology. At low Q, the amount of solvent that penetrates into the film is limited and it cannot induce enough chain mobility. Thus, thin film shows short stripes or a worm‐like structure. At high Q, the great diffusion of solvent into the film facilitates polymer mobility, leading to an ordered structure. Our results also suggested that the dewetting mechanism of thin film depends on Q. At low Q, dewetting develops via the nucleation and growth. At high Q, the condensation of solvent on the surface removes some polymer and dewetting is dominated by spinodal mechanism. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers 相似文献
115.
Air Quality Monitoring Network Design to Control Nitrogen Dioxide and Ozone,Applied in Granada,Spain
Antonio Lozano José Usero Eva Vanderlinden Juan Raez Juan Contreras Benito Navarrete 《臭氧:科学与工程》2011,33(1):80-89
This paper describes a method to design air quality monitoring networks for nitrogen dioxide and ozone and its application in Granada, a city located in Andalusia, southern Spain. The city has a population of 236,988 inhabitants, and traffic is its main source of air pollution. Sampling campaigns with passive diffusion samplers at 88 sites were carried out to obtain information on the pollution distribution in Granada. The average concentrations found for NO2 and O3 were 36.5 μg/m3 and 51.6 μg/m3, respectively. Maximum values of up to 57.1 μg/m3 NO2 were found in Granada city center and O3 reached 77.2 μg/m3 downwind from the emission source. After spatial interpolation of the obtained values with Geographical Information Systems, a selection of the best locations for the monitoring stations was made, in line with the macro- and microscale siting requirements of the European Directive 2008/50/EC on ambient air quality and cleaner air for Europe. Another sampling campaign with diffusive samplers was carried out in 2007 to determine if the locations of the air quality assessment stations were still representative for their zone. A correction was made in the control network following results of this verification campaign. 相似文献
116.
This paper analyses the deployment of wind power and the related local controversies using actor-network theory (ANT). ANT provides conceptual instruments for a fine-tuned analysis of the contingencies that condition a project’s success or failure by focusing on the micro-decisions that intertwine the material aspects of the technology, the site where it is implemented, the participation process, and the social relations in which they are embedded. By considering controversies as alternative efforts of competing networks of actors to ‘frame’ the reality and enroll others, ANT sheds light on the complex and political nature of planning a wind farm project, insofar as it consist in aligning material and human behaviours into a predictable scenario. ‘Overflows’ occur when actors do not conform to expectations, adopt conflicting positions and develop their own interpretations of the project, thus obliging designers to adapt their frames and change their plans. To demonstrate this framework, we apply it to the case of a wind farm project in the South of France, near Albi. Our analysis suggests a new approach to examining wind power projects in terms of the interaction between globally circulating technologies, unique characteristics of the site, the participation process and the social dynamics that emerge when these are combined. 相似文献
117.
Zuzana Živcová Martin Černý Willi Pabst Eva Gregorová 《Journal of the European Ceramic Society》2009,29(13):2765-2771
The elastic properties, in particular the tensile modulus (Young's modulus) and Poisson ratio, of porous alumina, zirconia, and alumina–zirconia composite ceramics are studied using the resonance frequency method and the results compared with theoretical predictions. Starch is used as a pore-forming agent, so that the resulting microstructure is essentially of the matrix-inclusion type (with large bulk pores, connected by small throats when a percolation threshold is exceeded). It is found that for this type of microstructure the porosity dependence of the Young's modulus is significantly below the upper Hashin–Shtrikman bound and the power-law prediction; it corresponds well, however, to a recently proposed exponential relation and to an empirical volume-weighted average of the upper and lower Hashin–Shtrikman bounds. Results for all three types of ceramics indicate that – in the porosity range considered, i.e. up to approximately 50% – the Poisson ratio depends only slightly on porosity. 相似文献
118.
Funseth E Påhlman M Eloranta ML Friman G Ilbäck NG 《The Science of the total environment》2002,284(1-3):37-47
During acute infections, the synthesis of acute-phase proteins and other proteins participating in the host defence are stimulated in the liver and kidney. In previous studies of coxsackievirus B3 (CB3) infection in mice, we found that cadmium (Cd) accumulates in the kidney, whereas 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) accumulates in the liver. To study if CB3 infection affects the synthesis of the Cd-binding protein metallothionein (MT) and the TCDD-binding/detoxifying cytochrome P-450 (CYP-450) isozyme CYP1A1, the basal and TCDD-induced levels of serum MT and liver CYP1A1 isozyme were determined in healthy and CB3-infected A/J mice. Furthermore, because interferons affect CYP450 activity, the serum levels of the interferons alpha (IFN-alpha) and -beta (IFN-beta) were measured in CB3-infected mice and in mice treated with the interferon-inducer polyinosinic/polycytidylic acid (poly I/C). Virus or poly I/C was administered intraperitoneally (i.p.) on day 0 and 500 ng TCDD/kg bodyweight on day 1. On day 4, CB3 infection had induced MT approximately 10-fold, regardless of TCDD treatment (P < 0.01 in infected mice and P < 0.001 in infected, TCDD-treated mice). TCDD alone induced a 10-fold increase in CYP1A1 activity (P < 0.001), whereas infection alone suppressed the normal CYP1A1 activity by 75% (P < 0.001). Infection also suppressed the TCDD-induced CYP1A1 activity by approximately 30% (n.s.). Poly I/C suppressed CYP1A1 by 20-25% (n.s.) at both basal and TCDD-induced levels. Serum IFN-alpha and IFN-beta levels were undetectable in controls, in TCDD-treated and in the poly I/C-treated groups on day 4, probably because the short IFN peak is detectable only hours after injection. Conversely, on day 4 of the infection, IFN-alpha and IFN-beta were consistently raised in the TCDD-treated infected mice, whereas increased IFNs as a result of infection alone could be detected in only one individual. These results suggest that the normal host responses during acute infections down-regulate detoxifying processes in favour of acute-phase protein synthesis. This may explain the observed changed pattern of accumulation, excretion and toxicity of the environmental pollutants cadmium and TCDD during this common virus infection. 相似文献
119.
As scholars in fields such as media studies, crisis studies and public policy studies have argued, there exists a fundamental link between crises and the media. Once an event has been interpreted as a crisis, questions of accountability inevitably appear on the media agenda, and the struggle to attribute blame and responsibility to a specific entity or entities—the blame game—thus becomes an inexorable part of the crisis process. Focusing on three liberal Western newspapers with an international, primarily Western elite readership and a reputation for in‐depth analysis of global events, The Economist, the Financial Times and the International Herald Tribune, this article employs Iyengar's and Valkenburg's notions of responsibility frames to examine whether initial coverage of the 2003 SARS crisis in these accounts held any particular entity accountable for the crisis, looks at three key themes used to communicate to the reader a particular way of thinking about responsibility for SARS and examines some of the consequences of the kind of responsibility frame constructed around the SARS crisis in these accounts. As our findings show, there is an entity that the early news accounts studied consistently held responsible for the 2003 SARS crisis, the Chinese system, and the corresponding responsibility frame at operation in these accounts is thematic rather than episodic in nature, since it consistently places the SARS crisis within a broader context (a product of “China” itself and/or of societal‐governmental forces in China) rather than in relation to a specific episode or as the result of the particular actions of individuals. The SARS crisis narrative therefore presented in these accounts tells the story of an anachronistic Chinese system faced with a contemporary health threat that, by its very nature, it is incapable of assessing accurately or managing responsibly. By way of conclusion, we argue that, while the use of such a thematic frame to explain China's role in the 2003 SARS crisis may be accurate in certain respects, this frame falls short in other respects and proves particularly inadequate to the challenge of capturing the economic complexities of China's role during the crisis. 相似文献
120.
There is much evidence that parents' perceptions of children's competence affect the development of children's academic functioning. In the current research, the possibility that this is moderated by parents' theories about the stability of competence was examined. In a 2-wave, 1-year study of 126 children (9 to 12 years old) and their mothers, children's academic functioning (i.e., grades, perceptions of competence, attributions for performance, and mastery orientation) and affective functioning (i.e., self-esteem and depressive symptoms) were examined. Among mothers with relatively high entity theories, their perceptions acted as self-fulfilling prophecies foreshadowing children's academic and affective functioning over time. However, among mothers with relatively low entity theories, mothers' perceptions did not predict children's academic and affective functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献