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121.
Isabela Butnar Julio Rodrigo Carles M. Gasol Francesc Castells 《Biomass & bioenergy》2010,34(12):1780-1788
Through the Renewable Energies Plan 2000–2010, Spain has fixed the objective of covering 12% of the primary energy demand from renewable sources. The achievement of this objective implies an annual increase of 22.4% of the energy produced from renewable sources. In this context, the objective of this study is to determine if the electricity from biomass produced in Spain would be environmentally competitive with electricity from natural gas or from the Spanish electricity mix. For that, the environmental impacts associated to the whole life cycle of two energetic crops in Spain, Poplar and Ethiopian mustard, used for power generation were evaluated. The overall assessment includes the cultivation and collection of biomass, its transport and the processes of its energetic transformation. We calculated different scenarios of electricity production from biomass in different capacity power plants (10, 25 or 50 MW), different transport scenarios and different productivities for biomass production. Our results show that, given the assumptions of this study, Ethiopian mustard is more impacting than Poplar when used for electricity production. Also, the transportation of biomass from the field to the power plant is an important stage that has to be carefully planned in order to get the maximum amount of electricity with a minimum environmental impact. Compared to electricity from natural gas or the Spanish electricity mix, the electricity obtained from biomass is more impacting in three from six impact categories we present here. 相似文献
122.
In component-based development, software components are taken as units of composition. Nevertheless, to achieve the widely disseminated status of components being plugged together as simple ‘Lego Pieces’, the integration of components must be carefully designed, systematised and verified; only this can ensure reliable architectures. In this work, we propose some conformance notions to predict the precise nature of some forms of composition, considering coordination patterns used in the integration. These notions are formalised in terms of the denotational semantics of the process algebra CSP, and assist the designer in common activities during integration, such as the substitution of component specifications by implementations, contract adaptations, and system extensions. To support mechanical verifications using FDR (a model-checker for CSP), we derive test characterisations from the denotational definitions of conformance. We illustrate the application of these notions through a systematic composition strategy of software frameworks, and we mechanically verify the preservation of behavioural component properties in these compositions. Moreover, we characterise the well-formedness of a coordination pattern used in this strategy at the design stage, before components are assembled. 相似文献
123.
O. Martínez-Matos J. A. Rodrigo M. L. Calvo V. Hevia-Martín P. Cheben 《Optical Memory & Neural Networks》2009,18(1):21-24
The properties of a photopolymerizable glass modified with high refractive index species incorporated at molecular level,
including a wide range of spatial frequencies and the recording kinetics, are analyzed. Implementation of emerging applications
is proposed.
The article is published in the original. 相似文献
124.
Mnica Mendes Fbris Kossoski Ana I. Lozano Joo Pereira-da-Silva Rodrigo Rodrigues Joo Ameixa Nykola C. Jones Sren V. Hoffmann Filipe Ferreira da Silva 《International journal of molecular sciences》2021,22(12)
We report absolute photoabsorption cross sections for gas-phase 2- and 5-bromopyrimidine in the 3.7–10.8 eV energy range, in a joint theoretical and experimental study. The measurements were carried out using high-resolution vacuum ultraviolet synchrotron radiation, with quantum chemical calculations performed through the nuclear ensemble approach in combination with time-dependent density functional theory, along with additional Franck–Condon Herzberg–Teller calculations for the first absorption band (3.7–4.6 eV). The cross sections of both bromopyrimidines are very similar below 7.3 eV, deviating more substantially from each other at higher energies. In the 7.3–9.0 eV range where the maximum cross-section is found, a single and broad band is observed for 5-bromopyrimidine, while more discernible features appear in the case of 2-bromopyrimidine. Several π* ← π transitions account for the most intense bands, while weaker ones are assigned to transitions involving the nitrogen and bromine lone pairs, the antibonding σ*Br orbital, and the lower-lying Rydberg states. A detailed comparison with the available photo-absorption data of bromobenzene is also reported. We have found significant differences regarding the main absorption band, which is more peaked in bromobenzene, becoming broader and shifting to higher energies in both bromopyrimidines. In addition, there is a significant suppression of vibrational structures and of Rydberg states in the pair of isomers, most noticeably for 2-bromopyrimidine. 相似文献
125.
This paper deals with national systems of innovation (NSIs) from a Latin American perspective. It begins by looking into the related conceptualization elaborated in the North with a "Southern head", stressing some characteristics of the NSIs concept that are helpful to understand Southern specificity: its ex-post nature, the normative weight it carries, its "relational" features, the fact that it describes a purposeful policy subject and not only an outcome of evolutionary patterns. Then the paper describes some contextual differences between Latin America and the developed nations in terms of the NSIs conceptualization. This is followed by an abbreviated account of empirical findings gathered from recent innovation industrial surveys in Latin America. It also briefly describes some of the findings of a methodological attempt to construct a picture of the NSI in a small Latin American country, Uruguay. Finally, some lessons stemming from more mature systems of innovation are outlined. 相似文献
126.
Rodrigo S. da Silveira Andréa M. de Oliveira Sibele B. C. Pergher Victor Teixeira da Silva Ione M. Baibich 《Catalysis Letters》2009,129(3-4):259-265
Palladium and/or molybdenum catalysts supported on mordenite were prepared and characterized by XRD, UV–vis, DRS, textural properties analysis, TPR, TPD and chemical analysis. The Mo-catalyst rapidly deactivated after the first minutes reaction. The Pd-catalysts were active in the NO decomposition reactions. The incorporation of Mo in the Pd-catalysts improved their catalytic properties. 相似文献
127.
128.
P Caizares J García‐Gmez F Martínez MA Rodrigo 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(5):533-539
A simple batch distillation process for the treatment of two types of industrial waste generated in a metalworking factory has been evaluated. Both types of waste are oil‐in‐water emulsions composed of numerous compounds and each type has a high content of water‐soluble species. The water‐soluble nature of the wastes precludes the use of conventional treatment technologies, such as ultrafiltration or chemical emulsion breaking, since they need to be complemented with additional treatment processes that would probably increase the cost considerably. A simple characterization of the liquid–vapour equilibrium and a scale‐up study has demonstrated the applicability of this technology. The process allows 90% of the waste to be recovered as water, thus achieving the required quality limits for discharge into a municipal wastewater treatment plant. An approximate estimation of capital investment and operating costs for an existing case has shown the economic viability of this process. Copyright © 2004 Society of Chemical Industry 相似文献
129.
130.
Meriane Cristine dos Santos Patrícia S. Oliveira Patricio Rodrigo Lambert Orfice 《Polymer Composites》2016,37(5):1342-1349
Materials that can switch from stiff to soft or from brittle to tough by slightly changing the temperature, pH, electric, or magnetic fields of their environments, can have a pronounced impact on many applications, including sensors, biomedical materials for less invasive surgeries, and packaging materials. In this work, temperature‐sensitive poly(N‐isopropyl acrylamide) grafts and low molar mass polyethylene glycol were incorporated in the interfacial region between clay nanoparticles and a bacteria‐derived polyhydroxybutyrate matrix to determine if the application of an external stimulus, such as small changes in temperature, could increase the toughness of the nanocomposites. The obtained materials were characterized by using thermal analysis, infrared spectroscopy, dynamic light scattering and dynamic mechanical tests. Mechanical properties were also evaluated at different temperatures and showed that small changes in temperature, such as from 25°C to 40°C, led to a pronounced increase in strain at break of the nanocomposites containing the modified interface. The external stimulus associated with the increase in temperature from 25°C to 40°C can reduce the interfacial interactions between clay and polymer matrix and create a highly plasticized polymer layer between the components of the nanocomposite, which favored the sliding of the interface and ultimately led to high values of elongation. POLYM. COMPOS., 37:1342–1349, 2016. © 2014 Society of Plastics Engineers 相似文献