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941.
C.M.V.B. Almeida A.J.M. Rodrigues S.H. Bonilla B.F. Giannetti 《Journal of Cleaner Production》2010,18(1):32-43
The life of a product begins with the initial product design concepts; the costs and potential impacts of a product are heavily influenced by the final design, the production processes, the economic and environmental costs of all raw materials. Additionally, both of these factors are very much affected by how the products are managed during and after consumer usage. Thus, there is an urgent need for a tool to facilitate the integration and assessment of environmental and economic demands into the product planning and development processes. The introduction of environmental accounting based on emergy as a tool to assist in product design is proposed. This complementary tool may be inserted into the conventional design methodology to facilitate in the selection of materials and processes as well as in the actual design of the products. To illustrate the application of the proposed method for material selection, PET (polyethylene terephthalate) bottles and aluminum cans for beverage packaging are compared. Despite the exceptional condition of aluminum recycling in Brazil, results show that the best option for beverage packages is the PET bottles. 相似文献
942.
Silvia H. Bonilla Rodrigo L. Guarnetti Cecilia M.V.B. Almeida Biagio F. Giannetti 《Journal of Cleaner Production》2010,18(1):83-91
Bamboo presents physical and mechanical characteristics, which turn it an alternative option for product development, replacing native or reforested wood. The sustainability assessment of a Dendrocalamus Giganteus species plantation in Brazil through the emergy methodology evidences a great weight of renewable (30% sej/sej) and human labour contributions (33% sej/sej). These contributions account for the great interface with environment and to the intensive work, respectively. The transformity value of bamboo production is 2.42E + 04 sej/J. The influence human labour has on the total emergy flow and on indicators is evaluated by taking into account different country locations (Brazil, Australia and China). Thus, a different transformity value for labour is assumed for each country. A ranking based on emergy sustainability index (ESI) values shows that bamboo production in China was the first placed, followed by Brazil and Australia (values of 1.18, 0.50 and 0.09, respectively). The insertion of indirect renewability embedded in labour results in the ranking modification, leading to plantation in Brazil in the first place, followed by the Australian and Chinese ones. The relative position of the bamboo systems is visualized in the ternary diagram expressed in terms of emergy. In an attempt to explore the relationship between sustainability and time, a graphic of ESI vs. global productivity is discussed in terms of a prospective evaluation. Indirect support areas of the bamboo production are calculated as a way to evaluate the sustainability-space relationship. 相似文献
943.
944.
The ultrastructure of the genera Althornia, Aplanochytrium, Japonochytrium, Schizochytrium and Thraustochytrium is described, and all are regarded as members of the new order Thraustochytriales Sparrow. Species considered are Althornia crouchii, Aplanochytrium kerguelensis, Hyalochlorella marina, Japonochytrium sp., Schizochytrium aggregatum, Thraustochytrium kinnei and T. striatum. All but H. marina are, on ultrastructural evidence, related genera, and some speculative suggestions are made about possible interrelationships both between the species discussed, between the Thraustochytriales and Labyrinthulales, and between these two and other major taxa. 相似文献
945.
K L Steffey J Mack C W MacMonegle H B Petty 《Journal of environmental science and health. Part. B》1984,19(1):49-65
Milk supplies in Illinois were monitored for chlorinated hydrocarbon insecticide residues from 1972 through 1981. The percentage of milk samples that were contaminated with aldrin/dieldrin, DDT and its analogs, and BHC/lindane decreased during the 10-year sampling period. The percentage of samples contaminated with aldrin/dieldrin decreased from 98.7% in 1978 to 5.9% in 1981. The amount of aldrin/dieldrin residues found in contaminated samples also decreased from an average of 0.077 ppm (1972-79) to 0.001 ppm in 1980-81. The levels of chlordane and heptachlor/heptachlor epoxide residues in milk did not decrease, but residues of BHC and DDT decreased gradually over the 10-year period. The percentage of samples that had less than 0.1 ppm of all chlorinated hydrocarbon residues combined ranged from 10.6% to 25.7% during 1972 through 1978 and increased to 36.2% in 1979, 71.1% in 1980, and 61.4% in 1981. 相似文献
946.
Timothy B. Spruill 《Journal of the American Water Resources Association》1983,19(6):977-981
ABSTRACT: Data from 54 well in central and eastern Kansas developed in unconsolidated deposits of Quaternary age indicate that nitrate concentrations are inversely related to the depth of the well screen opening below the water level in the well casing because this relationship was found to exist in an area of Nebraska and in a large area of Kansas, the relationship is generally valid over a wide geo- graphical area. In addition, the data indicate that the incidence of nitrate concentrations exceeding 45 milligrams per liter and nitrate concentrations, in general, are significantly lower in water from wells with screens deeper than 25 feet below the water table in unconfined aquifers or where screens are placed in deep confined aquifers. No concentrations of nitrate greater than 45 milligrams per liter were in obseved wells where screens were deeper than 60 feet below the casing water level. These findings suggest that general placement of well screens as far below the water table as possible in unconfined unconsolidated aquifers in Kansas. and possibly other areas of the Midwest, may be an effective measure in preventing undesirable nitrate concentrations in ground water supplies. particularly in areas where nitrate is a problem. 相似文献
947.
Both hot pipe and dilution chamber samples of the exhaust from a diesel (Oldsmobile 350) engine have been collected, extracted with methylene chloride and those extracts have been tested for mutagenicity in forward mutation assays in human lymphoblasts and S. typhimurium. In the absence of a metabolic activation system, the extract was significantly mutagenic to the bacteria in the range of 0 to 30 μg/ml, but introduced no mutations in human cells at concentrations up to 200 μg/ml under the same conditions of assay medium. However, when assayed in the presence of a postmitochondrial supernatant derived from rat liver, the the soot extracts were significantly mutagenic to both bacteria and human cells in the range of 50–100 μg/ml. Fractionation of the soot extract on the basis of polarity by sequential elution from a silicic acid column permitted concentration of the mutagenic activity in the alkane/toluene eluate, as determined by bacterial assays. Preliminary characterization of this fraction and preliminary studies of pure compounds leads us to suspect the alkyl substituted phenanthrenes as representing at least a significant fraction of the mutagenic activity of this alkane/toluene eluate. 相似文献
948.
The growth-promoting activities of three different bovine sera have been compared in primary and secondary amniotic fluid cell cultures. In secondary amniotic fluid cell micro- cultures, aseptically collected calf serum (CS) was slightly, though not significantly more effective than fetal calf serum (FCS) in promoting DNA synthesis, while newborn calf serum (NCS) was significantly less effective than either CS or FCS. All three sera were optimally effective at concentrations of 10 per cent (v/v). Significant variation in quality occurred within four batches of each of CS and FCS, but not within four batches of NCS. A selected batch of CS was significantly more effective in promoting the growth of primary amniotic fluid cell cultures than were a number of batches of FCS then in routine laboratory use. It is suggested that CS may serve as an effective and economical alternative to FCS in the culture of amniotic fluid cells, thereby expanding the scope of serum batch testing. A possible explanation for the varying growth-promoting activities of different sera is discussed. 相似文献
949.
950.