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911.
912.
Lino Tralhão João Coutinho-Rodrigues Luís Alçada-Almeida 《Waste management (New York, N.Y.)》2010,30(12):2418-2429
The location of multi-compartment sorted waste containers for recycling purposes in cities is an important problem in the context of urban waste management. The costs associated with those facilities and the impacts placed on populations are important concerns. This paper introduces a mixed-integer, multiobjective programming approach to identify the locations and capacities of such facilities. The approach incorporates an optimization model in a Geographical Information System (GIS)-based interactive decision support system that includes four objectives. The first objective minimizes the total investment cost; the second one minimizes the average distance from dwellings to the respective multi-compartment container; the last two objectives address the “pull” and “push” characteristics of the decision problem, one by minimizing the number of individuals too close to any container, and the other by minimizing the number of dwellings too far from the respective multi-compartment container. The model determines the number of facilities to be opened, the respective container capacities, their locations, their respective shares of the total waste of each type to be collected, and the dwellings assigned to each facility. The approach proposed was tested with a case study for the historical center of Coimbra city, Portugal, where a large urban renovation project, addressing about 800 buildings, is being undertaken. This paper demonstrates that the models and techniques incorporated in the interactive decision support system (IDSS) can be used to assist a decision maker (DM) in analyzing this complex problem in a realistically sized urban application. Ten solutions consisting of different combinations of underground containers for the disposal of four types of sorted waste in 12 candidate sites, were generated. These solutions and tradeoffs among the objectives are presented to the DM via tables, graphs, color-coded maps and other graphics. The DM can then use this information to “guide” the IDSS in identifying additional solutions of potential interest. Nevertheless, this research showed that a particular solution with a better objective balance can be identified. The actual sequence of additional solutions generated will depend upon the objectives and preferences of the DM in a specific application. 相似文献
913.
Percilia Cardoso Giaquinto Claudia Militão da Silva Berbert Helton Carlos Delicio 《Behavioral ecology and sociobiology》2010,64(6):1029-1035
Selection favors females that attend to reliable information about male genetic quality and fitness. Male nutritional condition
can be a significant sign of mate quality since poor nutrition can be related to reduced sperm quality, low sperm quantity,
sexually transmitted diseases, and parasites. We tested whether female Nile tilapia, Oreochromis niloticus, preferred the chemical cues of males that were well fed with high-protein diet over those fed with low-protein diet. Females
do not only discriminate between males but also show a preference for well-fed males, discriminating between the odors with
respect to nutritional state, suggesting that they were responding to a food-specific chemical cue. It is therefore likely
that nutritional condition is related to the production of pheromones in males. Our results suggest that information about
male nutritional state can be conveyed in chemical cues and that females attend to these cues during mate choice. 相似文献
914.
Ahmet Asan Suzan Sarıca Okten Burhan Sen 《Environmental monitoring and assessment》2010,164(1-4):221-231
Soil and air samples of seven different localities around Hamitabat Thermic Power Plant, 10 km far away from Luleburgaz/Kirklareli (Turkey), were taken between the years 2003 and 2004 with seasonal intervals. The samples were brought to the laboratory and their microfungal identifications were done. From the air samples, 737 microfungi colonies were isolated comprising 26 species belonging to eight genera. From soil samples, 170.6 × 104 colony-forming unit (CFU)/g was isolated from 33 species belonging to 16 genera. The most isolated genus from air samples was Alternaria (324 CFU, 43.96%), followed by Cladosporium (208 CFU, 25.52%) and Phoma (44 CFU, 5.40%). Penicillium was the most isolated genus from the soil samples with a value of 560,000 CFU/g (32.8%), followed by Fusarium (226,000 CFU/g, 13.12%) and Aspergillus (154,000 CFU/g, 9.03%). Among these species, Alternaria citri and Alternaria alternata are the most abundant species in air with 164 and 107 CFU, respectively, whereas Fusarium graminearum and Penicillium citrinum are the most abundant species in soil with CFU per gram values of 17.8 × 104 and 1.3 × 105. Correlation analysis was applied to determine whether or not there was a relationship between colony number of isolated fungal genera and meteorological factors. Some parameters of soil samples’ incontent during the research period were calculated using a computer analysis program. From the air samples, a positive correlation was found between relative humidity and Alternaria colonial counts and Cladosporium spore counts (r?=?0.912 and r?=?1.000, respectively). Similarly, with the analysis of soil samples, a positive correlation between colonial counts of Alternaria and soil pH and a positive correlation between colonial counts of Aspergillus and Penicillium and salt percentage concentration of soil were found. 相似文献
915.
Teresa Carvalho Fernando Durão Célia Ferreira 《Waste management (New York, N.Y.)》2010,30(11):2209-2215
The objective of the research was to apply froth flotation to separate post-consumer PET (Polyethylene Terephthalate) from other packaging plastics with similar density, in a continuously operated pilot plant. A representative sample composed of 85% PET, 2.5% PVC (Polyvinyl Chloride) and 11.9% PS (Polystyrene) was subjected to a combination of alkaline treatment and surfactant adsorption followed by froth flotation. A mineral processing pilot plant, owned by a Portuguese mining company, was adapted for this purpose. The experimentation showed that it is possible to produce an almost pure concentrate of PET, containing 83% of the PET in feed, in a single bank of mechanical flotation cells. The concentrate grade attained was 97.2% PET, 1.1% PVC and 1.1% PS. By simulation it was shown that the Portuguese recycling industry specifications can be attained if one cleaning and one scavenger stages are added to the circuit. 相似文献
916.
917.
Sait C. Sofuoglu Burak Yayla Pınar Kavcar Duygu Ates Cafer Turgut Aysun Sofuoglu 《Environmental science and pollution research international》2013,20(9):6178-6183
Olive tree leaf samples were collected to investigate their possible use for biomonitoring of lipophilic toxic substances. The samples were analyzed for 28 polychlorinated biphenyls (PCB) congeners. Twelve congeners were detected in the samples. PCB-60, 77, 81, 89, 105, 114, and 153 were the most frequently detected congeners ranging from 32 % for PCB-52 to 97 % for PCB-81. Σ12PCBs concentration varied from below detection limit to 248 ng/g wet weight in the sampling area, while the mean congener concentrations ranged from 0.06 ng/g (PCB-128?+?167) to 64.2 ng/g wet weight (PCB-60). Constructed concentration maps showed that olive tree leaves can be employed for the estimation of spatial distrubution of these congeners. 相似文献
918.
D. F. Parra D. S. Rosa J. Rezende P. Ponce A. B. Lugão 《Journal of Polymers and the Environment》2011,19(4):918-925
Poly(3-hydroxybutyrate) (PHB) was evaluated in blends with poly(ethyleneglycol) (PEG) of different weight average molecular
weight (Mw = 300, 600, 1,000 and 6,000). Irradiation of the PHB/PEG films was carried out to different levels of irradiation
doses (5 and 10 kGy) and the effects were investigated talking into consideration: thermal properties by differential scanning
calorimetry (DSC), perforation resistance, water vapor transmission rate and biodegradation in simulated soil. The addition
of plasticizer alters thermal stability and crystallinity of the blends. The improvement in perforation resistance due to
irradiation was regarded to be a result of the crosslinking effect. Also, biodegradation assays resulted in mass retention
improvements with increases in PEG molar masses, PEG concentration and irradiation dose. The irradiation process was shown
to hamper the biodegradation mechanism. 相似文献
919.
Farmers’ perception of sustainable agriculture and its determinants: a case study in Kahramanmaras province of Turkey 总被引:1,自引:0,他引:1
F. Füsun Tatlıdil İsmet Boz Hasan Tatlidil 《Environment, Development and Sustainability》2009,11(6):1091-1106
The primary purpose of this study was to assess in quantitative terms farmers’ perceptions of sustainable agriculture and
to determine how those are influenced by different socio-economic characteristics and information-seeking behavior of the
farmers. The study was conducted in Kahramanmaras province of Turkey and comprised a stratified sample of 208 farmers from
four districts of the province. The farmers rated each of the 21 selected sustainable agricultural practices for importance
on a 5-point scale, and the total of these ratings formed the sustainable agriculture perception index. The index score was
calculated for each farmer and was treated as the dependent variable in the stepwise regression analysis procedure. The independent
variables were such socio-economic characteristics as the farming system, the total and irrigated area of the farm, membership
of a cooperative society and participation in village administration, and age, education, and income of the farmer; components
of information-seeking behavior included use of the mass media (newspapers, radio, and television), use of the Internet, travel,
and participation in farming events. The results of the study showed that the higher the socio-economic status (more frequent
contact with extension services, higher education, ownership of land, etc.) and the greater the access to information, the
greater the perceived importance of sustainable agricultural practices. It is concluded that if policy-makers and extension
organizations concentrate on these factors, they are more likely to succeed in making farmers more favorably disposed toward
sustainable agriculture. 相似文献
920.
Ana Catarina Ferreira Silva Sónia Brazão Steve J. Hawkins Richard C. Thompson Diana M. Boaventura 《Marine Biology》2009,156(12):2591-2599
Wave action is known to influence the abundance and distribution of intertidal organisms. Wave action will also determine
the duration and suitability of various foraging windows (high-tide and low-tide, day and night) for predation and can also
affect predator behaviour, both directly by impeding prey handling and indirectly by influencing prey abundance. It remains
uncertain whether semi-terrestrial mobile predators such as crabs which can access intertidal prey during emersion when the
effects of wave action are minimal, are influenced by exposure. Here, we assessed the effect of wave action on the abundance
and population structure (size and gender) of the semi-terrestrial intertidal crab Pachygrapsus marmoratus on rocky shores in Portugal. The activity of P. marmoratus with the tidal cycle on sheltered and exposed shores was established using baited pots at high-tide to examine whether there
was activity during intertidal immersion and by low-tide searches. Because prey abundance varies along a wave exposure gradient
on most Portuguese shores and because morphology of crab chelipeds are known to be related to diet composition, we further
tested the hypothesis that predator stomach contents reflected differences in prey abundance along the horizontal gradient
in wave exposure and that this would be correlated with the crab cheliped morphology. Thus, we examined phenotypic variation
in P. marmoratus chelipeds across shores of differing exposure to wave action. P. marmoratus was only active during low-tide. Patterns of abundance and population structure of crabs did not vary with exposure to wave
action. Stomach contents, however, varied significantly between shores of differing exposure with a higher consumption of
hard-shelled prey (mussels) on exposed locations, where this type of prey is more abundant, and a higher consumption of barnacles
on sheltered shores. Multivariate geometric analysis of crab claws showed that claws were significantly larger on exposed
shores. There was a significant correlation between animals with larger claws and the abundance of mussels in their stomach.
Variation in cheliped size may have resulted from differing food availability on sheltered and exposed shores. 相似文献