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881.
Anna M.K. Gustafsson Mark R.StJ. Foreman Christian Ekberg 《Waste management (New York, N.Y.)》2014,34(10):1775-1782
Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1 h at 800 °C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS. 相似文献
882.
Biochar physicochemical parameters as a result of feedstock material and pyrolysis temperature: predictable for the fate of biochar in soil? 总被引:1,自引:0,他引:1
883.
Effects of Population Size and Food Stress on Fitness-Related Characters in the Scarce Heath, a Rare Butterfly in Western Europe 总被引:6,自引:0,他引:6
Abstract: Knowledge about the effects of inbreeding in natural populations is scarce, especially in invertebrates. We analyzed to what extent fitness-related traits in the scarce heath ( Coenonympha hero ), a butterfly, are affected by population size and isolation and whether differences in food quality influence these effects. We categorized nine populations as either large or small and isolated. Full-sib groups of offspring from 27 females were followed under seminatural conditions. Because of increased zygote mortality, egg hatchability was significantly lower in the small and isolated populations than in the large ones. Population category had no effect on larval weight under optimal conditions, but weight was significantly lower in the small-isolated category with low food quality. The effects of inbreeding can thus be hidden when conditions are benign but can appear under stress. Survival also differed significantly between population categories, and larval developmental time tended to be longer in the small-isolated category, irrespective of food conditions. We suggest that the differences in fitness between offspring from large and small isolated populations are at least partly due to inbreeding. This adds a further threat to a species that is already suffering from decreasing population sizes and increasing isolation among populations. 相似文献
884.
The Role of Disaggregation of Asset Values in Flood Loss Estimation: A Comparison of Different Modeling Approaches at the Mulde River,Germany 总被引:3,自引:0,他引:3
Anja Wünsch Ulrich Herrmann Heidi Kreibich Annegret H. Thieken 《Environmental management》2009,44(3):524-541
In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure
data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary
information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual
influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this
paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC)
data. The resulting disaggregated assets are validated and compared using census data of the residential building number on
the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses
due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the
help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must,
however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements
compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution
LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling
aspects. 相似文献
885.
Abel Duarte Alonso 《The Environmentalist》2009,29(4):388-397
Despite aquaculture’s contribution providing an additional food source or employment in rural areas, this industry is often
presented in a controversial way, including its impact on the environment. However, an argument can also be made in favour
of aquaculture operators and their efforts to follow environmentally sound practices. Along these lines, the present study
investigates operators’ stance on environmental sustainability from a group of 26 Western Australian marron growers. Overall,
the findings demonstrate growers’ commitment to grow marron environmentally, for instance, without the use of fertilisers
or feeding. Furthermore, respondents are in agreement with the potential effects of environmentally unfriendly practices,
especially as in many cases marron growing is a complement to rural activities such as horticulture and cattle farming. At
the other end, some operators voice concerns on a different environmental issue, namely, the challenge that increasing droughts
and lack of sufficient rain is posing to their industry. 相似文献
886.
A Comparative Approach for Ranking Contaminated Sites Based on the Risk Assessment Paradigm Using Fuzzy PROMETHEE 总被引:2,自引:0,他引:2
A ranking system for contaminated sites based on comparative risk methodology using fuzzy Preference Ranking Organization
METHod for Enrichment Evaluation (PROMETHEE) was developed in this article. It combines the concepts of fuzzy sets to represent
uncertain site information with the PROMETHEE, a subgroup of Multi-Criteria Decision Making (MCDM) methods. Criteria are identified
based on a combination of the attributes (toxicity, exposure, and receptors) associated with the potential human health and
ecological risks posed by contaminated sites, chemical properties, site geology and hydrogeology and contaminant transport
phenomena. Original site data are directly used avoiding the subjective assignment of scores to site attributes. When the
input data are numeric and crisp the PROMETHEE method can be used. The Fuzzy PROMETHEE method is preferred when substantial
uncertainties and subjectivities exist in site information. The PROMETHEE and fuzzy PROMETHEE methods are both used in this
research to compare the sites. The case study shows that this methodology provides reasonable results. 相似文献
887.
Kirk R. Vincent Jonathan M. Friedman Eleanor R. Griffin 《Environmental management》2009,44(2):218-227
Removal of nonnative riparian trees is accelerating to conserve water and improve habitat for native species. Widespread control
of dominant species, however, can lead to unintended erosion. Helicopter herbicide application in 2003 along a 12-km reach
of the Rio Puerco, New Mexico, eliminated the target invasive species saltcedar (Tamarix spp.), which dominated the floodplain, as well as the native species sandbar willow (Salix exigua Nuttall), which occurred as a fringe along the channel. Herbicide application initiated a natural experiment testing the
importance of riparian vegetation for bank stability along this data-rich river. A flood three years later eroded about 680,000 m3 of sediment, increasing mean channel width of the sprayed reach by 84%. Erosion upstream and downstream from the sprayed
reach during this flood was inconsequential. Sand eroded from channel banks was transported an average of 5 km downstream
and deposited on the floodplain and channel bed. Although vegetation was killed across the floodplain in the sprayed reach,
erosion was almost entirely confined to the channel banks. The absence of dense, flexible woody stems on the banks reduced
drag on the flow, leading to high shear stress at the toe of the banks, fluvial erosion, bank undercutting, and mass failure.
The potential for increased erosion must be included in consideration of phreatophyte control projects. 相似文献
888.
889.
Vernon G. Thomas 《The Environmentalist》2010,30(2):206-210
Lead from spent ammunition causes preventable lead exposure in wildlife and humans that may ingest it. Nontoxic substitutes
for lead ammunition exist but are not adopted widely because of hunter opposition. Other forms of lead exposure in the human
environment have been heavily regulated because there is no safe level of exposure. The use of lead ammunition should be regulated
similarly to protect wildlife from this common disease. 相似文献
890.
Process,Characterization and Biodegradability of Aliphatic Aromatic Polyester/Sisal Fiber Composites
Chin-San Wu 《Journal of Polymers and the Environment》2011,19(3):706-713
The biodegradability, morphology, and mechanical properties of composite materials made of Poly(butylene adipate-co-terephthalate) (PBAT) and sisal fiber (SF) were evaluated. Composites containing acrylic acid-grafted PBAT (PBAT-g-AA/SF)
exhibited noticeably superior mechanical properties due to greater compatibility between the two components. The dispersion
of SF in the PBAT-g-AA matrix was highly homogeneous as a result of ester formation between the carboxyl groups of PBAT-g-AA
and hydroxyl groups in SF and the consequent creation of branched and cross-linked macromolecules. Each composite was subjected
to biodegradation tests in Rhizopus oryzae compost. Morphological observations indicated severe disruption of film structure after 60 days of incubation, and both the
PBAT and the PBAT-g-AA/SF composite films were eventually completely degraded. Water resistance of PBAT-g-AA/SF was higher
than that of PBAT/SF, although weight loss of composites buried in Rhizopus oryzae compost indicated that both were biodegradable, even at high levels of SF substitution. The PBAT-g-AA/SF films were more
biodegradable than those made of PBAT, implying a strong connection between these characteristics and biodegradability. 相似文献