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331.
332.
This study discusses an online reporting system used for waste flow tracking (auditing) and investigation of violations. In contrast to systems used in other countries, this system requires waste generators and transporters, as well as the treatment, storage, and disposal facilities (TSDFs) to file online reports on the movement of industrial waste within 24 h of being shipped, received, or completely treated. This system also provides online analytical processing for reporters to analyze all their data, thereby encouraging self-management of waste. Currently there are 25,861 generators, 4,963 transporters, and 865 TSDFs in Taiwan that are required to file online reports. Approximately 80 % of all waste generated in Taiwan is reported using this system. More than 7,000 vehicles are equipped with a global positioning system (GPS) for waste tracking, among which over 2,000 transport hazardous waste. Disposal vehicles transmit their locations to the Control Center every 30 s. Database quality has been enhanced through auditing and inspection for more than 12 years since this system was established. It serves as a “single portal” for industrial waste management and facilitates informed decision making for resource exchange and material flow among various industries to achieve resource and environmental sustainability.  相似文献   
333.
In Houston, some of the highest measured 8-hr ozone (O3) peaks are characterized by sudden increases in observed concentrations of at least 40 ppb in 1 hr, or 60 ppb in 2 hr. Measurements show that these large hourly changes appear at only a few monitors and span a narrow geographic area, suggesting a spatially heterogeneous field of O3 concentrations. This study assessed whether a regulatory air quality model (AQM) can simulate this observed behavior. The AQM did not reproduce the magnitude or location of some of the highest observed hourly O3 changes, and it also failed to capture the limited spatial extent. On days with measured large hourly changes in O3 concentrations, the AQM predicted high O3 over large regions of Houston, resulting in overpredictions at several monitors. This analysis shows that the model can make high O3, but on these days the predicted spatial field suggests that the model had a different cause. Some observed large hourly changes in O3 concentrations have been linked to random releases of industrial volatile organic compounds (VOCs). In the AQM emission inventory, there are several emission events when an industrial point source increases VOC emissions in excess of 10,000 mol/hr. One instance increased predicted downwind O3 concentrations up to 25 ppb. These results show that the modeling system is responsive to a large VOC release, but the timing and location of the release, and meteorological conditions, are critical requirements. Attainment of the O3 standard requires the use of observational data and AQM predictions. If the large observed hourly changes are indicative of a separate cause of high O3, then the model may not include that cause, which might result in regulators enacting control strategies that could be ineffective.

Implications To show the attainment of the O3 standard, the U.S. Environmental Protection Agency (EPA) requires the use of observations and model predictions under the assumption that simulations are capable of reproducing observed phenomena. The regulatory model is unable to reproduce observed behavior measured in the observational database. If the large observed hourly changes were indicative of a separate cause of high O3, then the model would not include that cause. Inaccurate model predictions may prompt air quality regulators to enact control strategies that are effective in the modeling system, but prove ineffective in the real world.  相似文献   
334.
In this paper, we investigate whether people's knowledge of the past influences their preferences and values towards future landscape change. "Knowledge of the past" is one aspect of the information set held by individuals, and a well-established finding in economics is that changes in information can change preferences and values. The particular aspects of knowledge of the past we work with here are: (i) awareness of past landuse, as represented by woodland cover and (ii) awareness of differing and sometimes contradictory literary impressions of this past landscape. The case studies used here relate to prospective changes in woodland cover in two UK national parks, the Lake District and the Trossachs. We find that people who are made aware that the landscape has changed over time, or that perceptions of the landscape have changed over time, are more likely to favour changes to the current landscape (are less likely to favour the status quo). Knowledge of the past therefore seems to have an impact on preferences for future landscapes. We also investigate the impacts on preferences of how "special", how "wild" and how "worked in" people perceive the landscapes of these two national parks to be.  相似文献   
335.
This is an evaluation of the regional approach to controlling air pollution, in the light of the New York metropolitan experience, and recent federal and state legislative developments. Regional airsheds are defined and their administrative advantages delineated. The political difficulties involved in establishing and managing regional control districts, such as jurisdictional and regulatory problems, are also discussed. This paper touches upon the extent and adequacy of present day coordination and cooperation between agencies in the New York metropolitan area, as illustrated by the failure of the alert system during the Thanksgiving 1966 air pollution “episode.” The conflicting approaches of regional air quality commissions and the Mid-Atlantic States Air Pollution Control Compact are stressed. The desirability of such federal and state legislative proposals, and the advantages and drawbacks of special districts and other institutional arrangements to solve regional problems are also evaluated.  相似文献   
336.
Gaylor MO  Harvey E  Hale RC 《Chemosphere》2012,86(5):500-505
Polybrominated diphenyl ether (PBDE) flame retardants are added at percent levels to many polymers and textiles abundant in human spaces and vehicles, wherein they have been long assumed to be tightly sequestered. However, the mg kg−1 burdens recently detected in indoor dust testify to substantial releases. The bulk of released PBDEs remain in the terrestrial environment, yet comparatively little research focuses on this compartment. There, insects/arthropods, such as crickets, are the most abundant invertebrate organisms and facilitate the trophic transfer of contaminants by breaking down complex organic matter (including discarded polymers) and serving as food for other organisms. Our experiments revealed that house crickets (Acheta domesticus) provided uncontaminated food and free access to PUF containing Penta-BDE (8.7% dry wt) for 28 d accumulated substantial PBDE body burdens. Crickets allowed to depurate gut contents exhibited whole body burdens of up to 13.4 mg kg−1 lipid ΣPenta-BDE, 1000-fold higher than typically reported in humans. Non-depurated crickets and molted exoskeletons incurred even higher ΣPenta-BDE, up to 80.6 and 63.3 mg kg−1 lipid, respectively. Congener patterns of whole crickets and molts resembled those of PUF and the commercial Penta-BDE formulation, DE-71, indicative of minimal discrimination or biotransformation. Accumulation factor (AF) calculations were hampered by uncertainties in determining actual PUF ingestion. However, estimated AFs were low, in the range of 10−4-10−3, suggesting that polymer-PBDE interactions limited uptake. Nonetheless, results indicate that substantial PBDE burdens may be incurred by insects in contact with current-use and derelict treated polymers within human spaces and solid waste disposal sites (e.g. landfills, automotive dumps, etc.). Once ingested, even burdens not absorbed across the gut wall may be dispersed within proximate terrestrial food webs via the insect’s movements and/or predation.  相似文献   
337.
Solid growth is seen for the air pollution control industry for the rest of the century. Over the next twelve years purchases of particulate control equipment in the U.S. will grow at a rate considerably better than the GNP; growth rates in developing countries will be even higher. The portion of air pollution control expenditures represented by FGD systems is predicted to rise from its current level of 12 percent to 62 percent in 1991 if acid rain legislation is passed as predicted. A significant market is seen also for municipal, industrial and agricultural waste incinerators. Geography plays an important role in the strength of the industry; in the future, industrialized countries will be the sites of new designs and applications, while developing countries will be the life extension of the tried and proven designs. Industrywide, new product development is seen as an underused route to success.  相似文献   
338.
2-Chlorophenol (2-CP), 4-chlorophenol (4-CP) and 2,4-dichlorophenol (2,4-DCP) at initial concentrations of 10, 20, 50 and 100mg l(-1) were degraded in aqueous media by direct UV photolysis using dielectric barrier discharge XeBr( *) excilamp (283nm) in a flow-through photoreactor. The pseudo-first order rate constants were highest and half-life times were lowest for 4-CP. The rates of photolysis under the experimental conditions increased in the order: 2-CP<2,4-DCP<4-CP. The intermediates of photolysis were identified by GC-MS and HPLC. The evolution of hydroquinone and p-benzoquinone as major intermediates of 4-CP photolysis was monitored.  相似文献   
339.
A combined Lagrangian stochastic model with micro-mixing and chemical sub-models is used to investigate a reactive plume of nitrogen oxides (NOx) released into a turbulent grid flow doped with ozone (O3). Sensitivities to the model input parameters are explored for different source NOx scenarios. The wind tunnel experiments of Brown and Bilger (1996) provide the simulation conditions for the first case study where photolysis reactions are not included and the main uncertainties occur in parameters defining the turbulence scales, source size and reaction rate of NO with O3. Using nominal values of the parameters from previous studies, the model gives a good representation of the radial profile of the conserved mean scalar Γ¯NOx although slightly over predicts peak mean NO2 concentrations Γ¯NO2 compared to the experiments. The high dimensional model representation (HDMR) method is used to investigate the effects of uncertainties in model inputs on the simulation of chemical species concentrations. For this scenario, the Lagrangian velocity structure function coefficient has the largest impact on simulated Γ¯NOx profiles. Photolysis reactions are then included in a chemical scheme consisting of eight reactions between species NO, O, O3 and NO2. Independent and interactive effects of 22 input parameters are studied for two source NOx scenarios using HDMR, including turbulence parameters, temperature dependant rate parameters, photolysis rates, temperature, fraction of NO in total NOx at the source and background ozone concentration [O3]. For this reactive case, the variance in the predicted mean plume centre Γ¯O3 is caused by parameters describing both physical (mixing time-scale coefficient) and chemical processes (activation energy for the reaction O3+NO). The variance in predicted plume centre Γ¯NO2 and root mean square NO2 concentration γNO2, is strongly influenced by the fraction of NO in the source NOx, and to a lesser extent the mixing time-scale coefficient. Adjusting the latter gives improved agreement with the Brown and Bilger experiment. Some weak parameter interactions are observed.  相似文献   
340.

In the Portland, Oregon, metropolitan region, an urban growth boundary (UGB) was established in 1979 to protect farm and forest lands from urban encroachment. Most of the literature on the impact of Oregon's land-use legislation has been on the urban side of the issue—primarily the relative success Portland has had in containing urban sprawl. The landscape component of this rural transformation is typically considered only as a passive backdrop to urban expansion. Portland provides an excellent site to examine the relationship city-dwellers have to nearby agricultural areas. Rapid urban growth in the 1990s pushed suburban development to the edge of the UGB creating stark contrasts between urban and rural land uses in parts of the metropolitan area. This study examines the impact of the UGB on rural landscape change in Portland. We combine findings from land-use analysis and surveys of urban and rural residents to suggest ways to merge the amenity values of landscape with planning policy regarding the UGB.  相似文献   
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