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281.
Cyanotoxins, microcystins and cylindrospermopsin, are potent toxins produced by cyanobacteria in potable water supplies. This study investigated the removal of cyanotoxins from aqueous media by magnetophoretic nanoparticle of polypyrrole adsorbent. The adsorption process was pH dependent with maximum adsorption occurring at pH 7 for microcystin-LA, LR, and YR and at pH 9 for microcystin-RR and cylindrospermopsin (CYN). Kinetic studies and adsorption isotherms reflected better fit for pseudo-second-order rate and Langmuir isotherm model, respectively. Thermodynamic calculations showed that the cyanotoxin adsorption process is endothermic and spontaneous in nature. The regenerated adsorbent can be successfully reused without appreciable loss of its original capacity.  相似文献   
282.
Environmental Science and Pollution Research - The objective of this study was to monitor a newly constructed wetland (CW) in north Wales, UK, to assess whether it contributes to an improvement in...  相似文献   
283.
Ian Gough 《环境政策》2016,25(1):24-47
A framework is presented for thinking about state intervention in developed capitalist economies in two domains: social policy and environmental policy (and, within that, climate-change policy). Five drivers of welfare state development are identified, the ‘five Is’ of Industrialisation: Interests, Institutions, Ideas/Ideologies, and International Influences. Research applying this framework to the postwar development of welfare states in the OECD is summarised, distinguishing two periods: up to 1980, and from 1980 to 2008. How far this framework can contribute to understanding the rise and differential patterns of environmental governance and intervention across advanced capitalist states since 1970 is explored, before briefly comparing and contrasting the determinants of welfare states and environmental states, identifying common drivers in both domains and regime-specific drivers in each. The same framework is then applied to developments since 2008 and into the near future, sketching two potential configurations and speculating on the conditions for closer, more integrated ‘eco-welfare states’.  相似文献   
284.
Patterns of expansion of geographical ranges of red deer and Siberian roe deer in Yakutia during the 20th century are considered. The area inhabited by red deer in Yakutia has increased almost fourfold over the past 50 years, with an expansion of over 200000 km2 toward the northwest. The geographical range of roe deer in the Lena–Amga interfluve has also changed considerably during the same period. Roe deer sightings in the subarctic zone were reported. The structure of geographical ranges of the species under investigation in different ecological and geographical regions of Yakutia is discussed, and the factors influencing the transformation of geographical range borders are characterized.  相似文献   
285.
An analysis is made of the spatial variability of snowmelt water composition (within and between biogeocenoses), with regard to its long-term dynamics, in pine and spruce forests exposed to airborne industrial pollution from the Europe’s largest Severonikel Copper–Nickel Smelter Complex. Snowmelt waters from under the tree canopy, compared to those from intercrown areas, contain higher concentrations of chemical elements due to their washing and leaching from tree crowns. This is especially true of spruce forests, since the crowns of spruce trees have a high sorption capacity. Distinct trends in the long-term dynamics of snowmelt water composition, related to reduction of industrial emissions, are observed in background forest areas and defoliating forests but not in the vicinity of pollution sources. It is shown that the main factors determining these dynamics in forests of the Kola Peninsula are edificator tree species, airborne industrial pollution, and, possibly, an increase in the number of days with above-zero temperatures in the period of snow accumulation, which facilitates washing and leaching of chemical compounds from tree crowns.  相似文献   
286.
Increasing rates of deforestation in tropical forests have been linked to agriculturalists. A critical concern generating debate is how well communities of trees recover into a more species rich ecosystem after restoration planting. The aim of the study was to evaluate the pattern of recovery of communities of tree, assess the influence of Acanthus pubescens, Lantana camara and Pennisetum purpureum, on the recovery as well as how restoration planting facilitates recruitment of other native tree seedlings along a gradient of forest restoration in Kibale National Park, Uganda after evictions of illegal settlers. We studied six restoration forests ranging in age from 3 to 16 years, naturally regenerating and three primary forests. Our results showed that recovery with natural regeneration was more effective than restoration planting although the latter enhanced recruitment of other native tree seedling. Tree recovery was generally correlated with age so that species density and diversity increased although at different rates. A reverse pattern was found for dominance but no clear pattern was found for tree density (individual/ha). Communities of tree showed directional patterns of change however community composition were still distinct among the different forests. A. pubescens, L. camara and P. purpureum negatively correlated with species density, tree density and diversity but a positive correlation was found for dominance. Restoration planting can reestablish forests with high species density, tree density and diversity, but this is dependent on age and the extent of the herbs, grasses and shrubs cover in tropical forests.  相似文献   
287.
The paper describes results obtained in the development of a previous research. We study here, in fast firing, the sintering behaviour and measure some properties of tiles containing a mixture of 60 wt% of paper mill sludge and 40 wt% of glass cullet. The behaviour of this material is compared to those displayed by materials obtained by the same mixture added with 10, 20 and 30 wt% of a natural red clay. In parallel, the same properties are measured also on a reference blend, which is presently used to produce commercial tiles. We show that powders containing 60 wt% of paper sludge and 40 wt% of glass cullet to which 30 wt% of clay is added give rise to materials that display a stable sintering process and have good hardness and strength and therefore could be used for the industrial production of tiles.  相似文献   
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