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611.
Environmental vulnerability analysis has been sparsely used in environmental performance evaluation (EPE) of technological innovations. The present paper proposes a methodological approach to carry out vulnerability analysis of watersheds and to integrate this analysis into methods of environmental performance evaluation of agro-industrial innovations. This approach is applied to the Ambitec-Life Cycle method, described in Part 1 (this issue) of this study. The case study of green coconut substrate compared to ripe coconut substrate, also described in Part 1 (this issue), is now presented considering the vulnerability analysis of the watersheds where the life cycle stages of these products occur. The integration of vulnerability analysis in Ambitec-Life Cycle contributes to a better understanding of the environmental aspects of agro-industrial technological innovations with potential to cause significant impacts in watersheds where these innovations are implemented.  相似文献   
612.
This study uses the process simulator ASPEN Plus® and Life Cycle Assessment (LCA) to compare three process design alternatives for biodiesel production from waste vegetable oils that are: the conventional alkali-catalyzed process including a free fatty acids (FFAs) pre-treatment, the acid-catalyzed process, and the supercritical methanol process using propane as co-solvent. Results show that the supercritical methanol process using propane as co-solvent is the most environmentally favorable alternative. Its smaller steam consumption in comparison with the other process design alternatives leads to a lower contribution to the potential environmental impacts (PEI’s). The acid-catalyzed process generally shows the highest PEI’s, in particular due to the high energy requirements associated with methanol recovery operations.  相似文献   
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Molecular techniques and modelling are presented as powerful tools required in the performance of efficient soil and water bioremediation systems. An Escherichia coli CC118-D strain was constructed by inserting the Klebsiella pneumoniae hpa B gene, coding for the unstable 3,4-dihydroxyphenylacetate 2,3-dioxygenase, into its chromosome. When the constructed strain was immobilized, both enzyme stability and viability increased along the studied period, in absence of antibiotic. We proposed this strategy as an approach to overcoming plasmid instability and to enhance enzyme activity and stability, avoiding antibiotic utilization. A model was developed to understand and predict the behaviour of bacteria and pollutants in a bioreactor system, considering: fluid dynamics, molecular/cellular scale processes and biofilm formation.  相似文献   
618.
High zinc ion concentrations produce an inhibitory effect on the naturally occurring hemolytic activity of theHolothuria polii coelomic fluid and coelomocyte lysate. The naturally occurring hemagglutinating activity remains unaffected. The inhibition appears reversible, suggesting a non-covalent interaction of the ions with the hemolysins. Moreover, as demonstrated by SDS-PAGE and immunoblotting analysis, the Zn++ treatment does not produce molecular weight variations in the coelomic fluid and coelomocyte lysate hemolytic patterns. This study was conducted during 1987 on samples gathered from the Gulf of Palermo, Italy.  相似文献   
619.
Copper sulphate has an adverse effect on some biochemical parameters of trout Salmo gairdneri. The main targets of damage are: (a)Tissue necrosis as demonstrated by increased ASAT and ALAT levels in blood plasma. (b)Inhibition of acetylcholinesterase activity. There is also a general stress effect as reflected by an elevated blood glucose level.  相似文献   
620.
The project ENMA assesses the atmospheric pollution caused by the transformation and consumption of energy. The project is in the following stages: (a) estimation of annual overall average emissions; (b) estimation of annual average concentrations of pollutants; and (c) estimation of doses. Estimation of annual overall average emissions is estimated, separately, for urban areas and point sources. Concentrations of pollutants are obtained for urban areas and point-sources by means of two different gaussian models. Finally, doses are calculated assuming that the effects of all pollutants are linear at low doses. Doses for each pollutant, and doses for exposure to several combined pollutants, are defined. The doses on population are also defined, assuming that the significance of pollution depends on the number of people exposed.  相似文献   
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