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141.
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   
142.
143.
Measurements of Benzo (a) Pyrene deposited on glass fiber filters exposed to solar radiation indicate a time dependent exponential decrease. Possible impli cations of this phenomenon in the measurements of B(a)P in particulate samples are discussed.  相似文献   
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145.
In a preceding study it has been reported that the freshwater sponge Lubomirskia baicalensis, living in Lake Baikal (East Siberia), is composed of spicules forming a characteristic pattern which follows radiate accretive growth. Here we report that the spicules are synthesized by the enzyme silicatein, a protein which is related to cathepsin L. The cDNAs for silicatein and the related cathepsin L were isolated and used as probes to show that the mRNA levels of silicatein in the bases of the spicule skeleton of the animals are low, while the mRNA level of cathepsin L in this region exceeds that of the growing zone. This is the first comprehensive study on the importance of the axial filament/silicatein as an essential structural and functional component determining the growth and stability of demosponge spicules.Note: Sequences from Lubomirskia baicalensis have been deposited in the EMBL/GenBank; cDNAs for the putative silicatein (LBSILICA) are deposited under the accession no. AJ786771 and for cathepsin L (LBCATL) under the accession no. AJ786770.  相似文献   
146.
This study presents the first survey of earthworm species (Oligochaeta) from Benghazi, a Mediterranean coastal city in Libya. A total of three peregrine species were recorded: Allolobophora caliginosa trapezoides, Allolobophora rosea (Family: Lumbricidae), Microscolex dubius (Family: Microscolecidae). Their distribution and density in six habitats (vegetable garden, flower garden, green house, farmland, grassland, plain barren landscape) are discussed in relation to some of the physico-chemical parameters and composition of the soil.  相似文献   
147.
The high availability of large quantities of turkey manure generated from turkey production makes it an attractive feedstock for carbon production. Pelletized samples of turkey litter and cake were converted to granular activated carbons (GACs) by steam activation. Water flow rate and activation time were changed to produce a range of activation conditions. The GACs were characterized for select physical (yield, surface area, bulk density, attrition), chemical (pH, surface charge) and adsorptive properties (copper ion uptake). Carbon physical and adsorptive properties were dependent on activation time and quantity of steam used as activant. Yields varied from 23% to 37%, surface area varied from 248 to 472 m(2)/g and copper ion adsorption varied from 0.72 to 1.86 mmol Cu(2+)/g carbon. Copper ion adsorption greatly exceeded the values for two commercial GACs. GACs from turkey litter and cake show considerable potential to remove metal ions from water.  相似文献   
148.
Results from two mathematical approaches to predict the toxicity of all the possible binary equitoxic mixtures of Co, Cd, Cu, Zn and Pb were compared to the observed toxicity of these mixtures to Vibrio fischeri bacteria. Combined effect of the metals was found to be antagonistic for Co-Cd, Cd-Zn, Cd-Pb and Cu-Pb, synergistic for Co-Cu and Zn-Pb and merely additive in other cases, revealing a complex pattern of possible interactions. Besides, Cd appears much less toxic to the bacterial model than to animal cells. The synergistic effect of the Co-Cu combination and the strong lowering of Pb toxicity in the presence of Cd deserve much attention when establishing environmental safety regulations.  相似文献   
149.
Gamma-hexachlorocyclohexane (gamma-HCH or lindane), one of the most commonly used insecticides, has been mainly used in agriculture. Organochloride compounds are known to be highly toxic and persistent, causing serious water and soil pollution. The objective of the present study is the evaluation of the anaerobic degradation of alpha-, beta-, gamma-, delta-HCH in liquid and slurry cultures. The slurry system with anaerobic sludge appears as an effective alternative in the detoxification of polluted soils with HCH, as total degradation of the four isomers was attained. While alpha- and gamma-HCH disappeared after 20-40d, the most recalcitrant isomers: beta- and delta-HCH were only degraded after 102d. Intermediate metabolites of HCH degradation as pentachlorocyclohexane (PCCH), tetrachlorocyclohexene (TCCH), tri-, di- and mono-chlorobenzenes were observed during degradation time.  相似文献   
150.
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