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11.
Innovations in water chain are discussed based on experiences in the Netherlands. The available and new technological options, as well as their dissemination in the Netherlands, are presented for the prevailing system with add-on technologies (elongation), and for the emerging separation system with technologies at the source. Numerous new options are available for both systems but these options are rarely used. The low use is explained using economic theories and with practical examples from the Netherlands. In order to foster innovations, the mainstream, evolutionary, and behavioral theories pinpoint respectively the pricing of common goods, broad support of concerted action, and support for innovators’ entry. These actions may all be needed. Experiences with a stakeholder cluster in water management suggest that markets for high value water use invoke innovations and low-cost technology adaptations. The systematic development of services that foster high value water-based activities is recommended.  相似文献   
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Studies that evaluate determinants of residential water demand typically use data from a single spatial scale. Although household‐scale data are preferred, especially when econometric models are used, researchers may be limited to aggregate data. There is little, if any, empirical analysis to assess whether spatial scale may lead to ecological fallacy problems in residential water use research. Using linear mixed‐effects models, we compare the results for the relationship of single‐family water use with its determinants using data from the household and census tract scales in the city of Phoenix. Model results between the household and census tract scale are similar suggesting the ecological fallacy may not be significant. Common significant determinants on these two spatial scales include household size, household income, house age, pool size, irrigable lot size, precipitation, and temperature. We also use city/town scale data from the Phoenix metropolitan area to parameterize the linear mixed‐effects model. The difference in the parameter estimates of those common variables compared to the first two scales indicates there is spatial heterogeneity in the relationship between single‐family water use and its determinants among cities and towns. The negative relationship between single‐family house density and residential water use suggests that residential water consumption could be reduced through coordination of land use planning and water demand management.  相似文献   
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Rates and direction of movement in the sand dollar Peronella lesueuri were measured in summer and winter in Cockburn Sound, a large coastal embayment in south-western Australia. P. lesueuri was found to have a diurnal activity pattern throughout the year and had a greater movement rate in the summer (mean of 5.3 cm h?1, day; 3.9 cm h?1, night) than in the winter (mean of 2.7 cm h?1, day; 2.0 cm h?1, night). Seasonal change in temperature and physiological requirements by the sand dollar are the most likely reason for the seasonal differences. Reasons for diurnal variation were not clear. Direction of movement was found to be random at both times of the year. Based on these movement rates, one sand dollar can bioturbate an approximate area of 0.1 m2 day?1 and 36.4 m2 year?1. At a conservative density estimate of 0.5 sand dollars per m2 it takes approximately 20 days for the sand dollars to rework the entire area of the sediments in the habitats they occupy.  相似文献   
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The field of engineering is changing rapidly as the growing global population puts added demands on the earth's resources: engineering decisions must now account for limitations in materials and energy as well as the need to reduce discharges of wastes. This means educators must revise courses and curricula so engineering graduates are prepared for the new challenges as practicing engineers. The Center for Sustainable Engineering has been established to help faculty members accommodate such changes through workshops and new educational materials, including a free access website with peer-reviewed materials.  相似文献   
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The results of more than 1 yr of air monitoring inside and outside of five homes in each of two communities are presented for SO2, NO2, mass respirable particles, SO4, Al, Br, Cl, Mn, Na, and V. Outdoor measurements across the home site in each city are consistent with proximity to outdoor sources. Looking across indoor residential sites in each city, the home appears to alter outdoor concentrations in several ways. Indoor level of SO2, SO4, Mn, and V are lower than those measured outdoors. These constituents are thought generally to result from outdoor sources. The other constituents studied are at times found in excess within homes. In some cases the source or sources of excess concentration of a particular constituent could be identified; often, however, the source of excess indoor concentration could not be identified.  相似文献   
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Procedures are developed and summarized that allow the calculation of the energy required to manufacture and install capital equipment, such as the material needed for a coalfired power plant. Three methods are available, each with certain strengths and weaknessess The first uses both literature value and national manufacturing statistics, the second uses a previously developed technique that disaggregates energy use according to how much each industry buys from all other industries, and the third technique is based on the average national relation between energy use and dollar flow. The most important differences between estimates of energy use by the different techniques relates to the inclusion or exclusion of labor and indirect expenditures rather than to differences in the data bases of the three techniques.  相似文献   
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Environmental Science and Pollution Research - Sustainable desalination can be achieved by adopting renewable energy-based low-cost and low-impact desalting techniques. In this investigation,...  相似文献   
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