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781.
John A. Ballweg Charles A. Ibsen 《Journal of the American Water Resources Association》1971,7(5):935-940
ABSTRACT. Evidence from 1969 studies in Virginia and Ohio suggests that neither community leaders nor the general public are likely to define water related problems as major problem areas. An examination of the components of a social problem tends to indicate that water problems have not moved beyond a level of minimal public concern. When respondents were willing to describe existing or potential water problems, perceptions as well as possible solutions were described in abstract rather than action-oriented terms. It is suggested that efforts to eliminate water resource problems are not likely to be effective until public concern moves to motivational and behavioral levels. 相似文献
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Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased. 相似文献
786.
Nongnuch Sutivisedsak Huai N. Cheng Charles S. Burks Judy A. Johnson Joel P. Siegel Edwin L. Civerolo Atanu Biswas 《Journal of Polymers and the Environment》2012,20(2):305-314
Nutshells are agricultural waste products that can be procured at relatively low cost. In this work we examined the possibility of using these biodegradable materials as fillers in poly(lactic acid) and low density polyethylene. The nutshells were ground into powder, blended with the polymer, and then injection molded with final weight varying from 10 to 40 weight %. The mechanical and thermal properties of the composites were then studied. In general, the addition of fillers caused reductions in mechanical properties to varying extents, but thermal properties were only slightly affected. The use of maleic anhydride and peroxide with the fillers had a negative effect on poly(lactic acid) but a slightly positive effect on the stiffness of polyethylene. The results suggested that polymer-nutshell composites may be usable in applications where cost is a concern and where some reductions in mechanical properties are acceptable. 相似文献
787.
Eadsforth Charles Austin Tom Bouvy Alain Cassani Giorgio DeFerrer Juanantonio Hager Claus-Dierk Schowanek Diederik Taeger Klaus Willing Andreas 《Environmental Sciences Europe》2013,25(1):1-9
The project focuses on the efficiency of combined technologies to reduce the release of micropollutants and bacteria into surface waters via sewage treatment plants of different size and via stormwater overflow basins of different types. As a model river in a highly populated catchment area, the river Schussen and, as a control, the river Argen, two tributaries of Lake Constance, Southern Germany, are under investigation in this project. The efficiency of the different cleaning technologies is monitored by a wide range of exposure and effect analyses including chemical and microbiological techniques as well as effect studies ranging from molecules to communities. 相似文献
788.
Charles E. Rodes Phil A. Lawless Jonathan W. Thornburg Ronald W. Williams Carry W. Croghan 《Atmospheric environment (Oxford, England : 1994)》2010,44(11):1386-1399
This analysis provides the initial summary of PM2.5 mass concentrations relationships for all seasons and participants for a general population in the Detroit Exposure and Aerosol Research Study (DEARS). The summary presented highlights the utility of the new methodologies applied, in addition to summarizing the particulate matter (PM) data.Results include the requirement to adjust the exposure data for monitor wearing compliance and measured environmental tobacco smoke (ETS) levels, even though the study design specified a non-smoking household. A 40% wearing compliance acceptance level was suggested as necessary to balance minimizing exposure misclassification (from poor compliance) and having sufficient data to conduct robust statistical analyses. An ETS threshold level equivalent to adding more than 1.5 μg m?3 to the collected sample was found to be necessary to detect changes in the personal exposure factor (Fpex). It is not completely clear why such a large threshold level was necessary.Statistically significant spatial PM2.5 gradients were identified in three of the six DEARS neighborhoods in Wayne County. These were expected, given the number of strong, localized PM sources in the Detroit (Michigan) metro area. Some residential outdoor bias levels compared with the central site at Allen Park exceeded 15%. After adjusting for ETS biases, the outdoor contributions to the personal exposure were typically larger by factors from 1.75 to 2.2 compared with those of the non-outdoor sources. The outdoor contribution was larger in the summer than in the winter, which is consistent with the fractions of time spent outdoors in the summer vs. the winter (6.7% vs. 1.1% of the time).Mean personal PM2.5 cloud levels for the general population DEARS cohort ranged from 1.5 to 3.8 (after ETS adjustment) and were comparable to those reported previously. The personal exposure collections indoors were typically at least 13 times greater than those contributed outdoors. 相似文献
789.
Phillip Alanis Shawn Ashkan Charles Krauter Sean Campbell Alam S. Hasson 《Atmospheric environment (Oxford, England : 1994)》2010,44(39):5084-5092
Recent studies suggest that dairy operations may be a major source of non-methane volatile organic compounds in dairy-intensive regions such as Central California, with short chain carboxylic acids (volatile fatty acids or VFAs) as the major components. Emissions of four VFAs (acetic acid, propanoic acid, butanoic acid and hexanoic acid) were measured from two feed sources (silage and total mixed rations (TMR)) at six Central California Dairies over a fifteen-month period. Measurements were made using a combination of flux chambers, solid phase micro-extraction fibers coupled to gas chromatography mass spectrometry (SPME/GC–MS) and infra-red photoaccoustic detection (IR-PAD for acetic acid only). The relationship between acetic acid emissions, source surface temperature and four sample composition factors (acetic acid content, ammonia-nitrogen content, water content and pH) was also investigated. As observed previously, acetic acid dominates the VFA emissions. Fluxes measured by IR-PAD were systematically lower than SPME/GC–MS measurements by a factor of two. High signals in field blanks prevented emissions from animal waste sources (flush lane, bedding, open lot) from being quantified. Acetic acid emissions from feed sources are positively correlated with surface temperature and acetic acid content. The measurements were used to derive a relationship between surface temperature, acetic acid content and the acetic acid flux. The equation derived from SPME/GC–MS measurements predicts estimated annual average acetic acid emissions of (0.7 + 1/?0.4) g m?2 h?1 from silage and (0.2 + 0.3/?0.1) g m?2 h?1 from TMR using annually averaged acetic acid content and meteorological data. However, during the summer months, fluxes may be several times higher than these values. 相似文献
790.
Charles A. Jones 《Journal of the Air & Waste Management Association (1995)》2013,63(3):268-272
Canada’s new Green Plan charts a course for dealing with environmental issues that will require an unflinching commitment to changes in thought, decision-making and action by all sectors of Canadian society. The five-year, $3-billion Plan lists 120 specific initiatives in eight areas of activity. It will enlist the participation of some 40 federal departments and agencies, alone, cooperatively or in creative partnerships with industry, the academic and scientific community, and citizens’ groups. 相似文献