62 research outputs found
Comparative analysis of the life cycle impact assessment of available cement inventories in the EU
Life Cycle Impact Assessment (LCIA) is one of basic steps in Life Cycle Assessment methodology (LCA). This paper presents a comparative study of the LCIA of different life cycle inventories (LCI) for EU cements. The analysis unit used is the manufacture of 1 kg of cement, from "cradle to gate". The impact categories considered are those resulting from the manufacture of cement and include greenhouse effects, acidification, eutrophication and summer and winter smog, amongst others.
The results of the study highlighted some inconsistencies in existing inventories. As for the LCIA, the main environmental interventions related to cement manufacture were classified and characterised and their effect on different impact categories analysed. Differences observed in evaluation of the impact of cement type were essentially related to their clinker content.Peer Reviewe
Comparative analysis of available life cycle inventories of cement in the EU
Life cycle inventories are a prerequisite of life cycle assessments. This paper conducts a comparative analysis of inventories of several different types of cement produced in Europe. It considers the production of 1 kg of cement from cradle to gate and all results are based on this mass unit. The reliability of cement inventories is affected by inaccurate or non-representative data, and comparative analysis is difficult due to varying system boundary definitions. Only the four main emissions (CO2, NOx, SO2 and dust) are considered. The theoretical model used gives reasonable estimates of emission levels and thus can serve as a reference to measured values. In the case of CO2, this is definitely a feasible alternative to in situ measurements. The emissions derive primarily from the production of clinker, both from the chemical reactions occurring in the kiln and by its fossil fuel consumption.Peer Reviewe
Fortalezas y debilidades de los inventarios de cementos para su empleo en análisis de ciclo de vida (ACV)
El análisis del ciclo de vida (ACV) de productos se ha convertido en una herramienta usual de cuantificación de aspectos medioambientales de
los mismos. Esta técnica, está bastante extendida en productos industriales estándar, pero no tanto, en productos del sector de la construcción,
como es el cemento. Por otro lado, para la realización de un ACV fiable es necesario contar con inventarios, asimismo fiables, lo cual adquiere
gran importancia ya que en España no existen de forma sistemática. En este artÃculo se hace un análisis de los inventarios públicos a los que
se ha tenido acceso, correspondientes a diferentes cementos del ámbito europeo, reflejándose las fortalezas y debilidades de los mismos.Peer Reviewe
Renormalization Group Functions of the \phi^4 Theory in the Strong Coupling Limit: Analytical Results
The previous attempts of reconstructing the Gell-Mann-Low function \beta(g)
of the \phi^4 theory by summing perturbation series give the asymptotic
behavior \beta(g) = \beta_\infty g^\alpha in the limit g\to \infty, where
\alpha \approx 1 for the space dimensions d = 2,3,4. It can be hypothesized
that the asymptotic behavior is \beta(g) ~ g for all values of d. The
consideration of the zero-dimensional case supports this hypothesis and reveals
the mechanism of its appearance: it is associated with a zero of one of the
functional integrals. The generalization of the analysis confirms the
asymptotic behavior \beta(g)=\beta_\infty g in the general d-dimensional case.
The asymptotic behavior of other renormalization group functions is constant.
The connection with the zero-charge problem and triviality of the \phi^4 theory
is discussed.Comment: PDF, 17 page
Assessment of the genotoxic impact of pesticides on farming communities in the countryside of Santa Catarina State, Brazil
The aim of this study was to assess the use of pesticides on farms located in the Lambedor River watershed in Guatambu, State of Santa Catarina, as well as to determine, by micronucleus testing, the risk of genotoxic impact. Samples from locally collected Cyprinus carpio, Hypostomus punctatus, Rhamdia quelen and Oreochromis niloticus gave evidence of a mean increase in micronuclei frequency from 6.21 to 13.78 in 1,000 erythrocytes, a clear indication of the genotoxic potenciality of pesticide residues in regional dams, and their significant contribution to local environmental contamination
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