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141.
Conventional wisdom has advocated environmental auditing as a prudent part of an internal control program and one of the key tools in driving proactive efforts. As a part of risk management activities, it is often employed to protect an organization and its employees and officers from liability. Conscientious use of such audits has undoubtedly protected human health and the environment. Ironically, those who make the most consistent efforts to audit compliance and management systems, according to advocates of audit protection, may be the most vulnerable to enforcement actions and lawsuits. In this, the second part of a two-part article, we turn our attention to the likely solutions for audit protection in the current context. 相似文献
142.
Anthony Donigian W. Henry Waggy 《Journal of the American Water Resources Association》1974,10(2):229-244
ABSTRACT: Proper economic evaluation of alternative plans will maximize the utility achieved from the resources available for water resource management. A knowledge of the frequency of occurrence of the events under study is necessary to fully utilize the advantages of economic evaluation in planning. Frequency information is widely used in flood control and water supply, but relatively unknown in water quality planning. A continuous, dynamic hydrologic and water quality model is presented to develop frequency curves for various water quality criteria. Results from the Denver Regional Water Quality Management Study are discussed as an example of the use of frequency analysis for economic evaluation of water quality management. 相似文献
143.
144.
Ambient air quality standards and control strategies are implemented to protect humans and vegetation from adverse effects. We used a process-based tree-growth model (TREGRO) to show that over the past 37 years, changes in O3 exposure, with accompanying variation in climate, are reflected in changes in the growth of Pinus ponderosa Dougl. ex Laws. in the San Bernardino Mountains near Los Angeles, California, USA. Despite variation in temperature and precipitation over the study period (1963–1999), O3 exposure consistently reduced simulated tree growth. Simulated growth reductions increased concurrent with increasing O3 exposure. The maximum growth reduction occurred in 1979. As O3 exposures decreased during the 1980s and 1990s, effects on growth also decreased. This implies that emission control strategies taken to reduce exposures to attain O3 standards benefited P. ponderosa growth in the San Bernardino Mountains. This modeling approach provides a powerful tool for solving the difficult problem of evaluating regulatory effectiveness by simulating plant response using long-term climate and air pollution exposure records for a given region.Phone 541 754-4621 Fax 541 754-4799 相似文献
145.
Brankov E Henry RF Civerolo KL Hao W Rao ST Misra PK Bloxam R Reid N 《Environmental pollution (Barking, Essex : 1987)》2003,123(3):403-411
We investigated the effects of transboundary pollution between Ontario and New York using both observations and modeling results. Analysis of the spatial scales associated with ozone pollution revealed the regional and international character of this pollutant. A back-trajectory-clustering methodology was used to evaluate the potential for transboundary pollution trading and to identify potential pollution source regions for two sites: CN tower in Toronto and the World Trade Center in New York City. Transboundary pollution transport was evident at both locations. The major pollution source areas for the period examined were the Ohio River Valley and Midwest. Finally, we examined the transboundary impact of emission reductions through photochemical models. We found that emissions from both New York and Ontario were transported across the border and that reductions in predicted O3 levels can be substantial when emissions on both sides of the border are reduced. 相似文献
146.
Processing and characterization of a new biodegradable composite made of a PHB/V matrix and regenerated cellulosic fibers 总被引:1,自引:0,他引:1
Ch. Bourban E. Karamuk M. J. de Fondaumière K. Ruffieux J. Mayer E. Wintermantel 《Journal of Polymers and the Environment》1997,5(3):159-166
In this study, a biodegradable composite consisting of a degradable continuous cellulosic fiber and a degradable polymer matrix—poly(3-hydroxybutyrate)-co-poly(3-hydroxyvalerate
(PHB/V with 19% HV)—was developed. The composite was processed by impregnating the cellulosic fibers on-line withPHB/V powder in a fluidization chamber. The impregnated roving was then filament wound on a plate and hot-pressed. The resulting
unidirectional composite plates were mechanically tested and optically characterized by SEM. The fiber content was 9.9 ±0.9
vol% by volumetric determination. The fiber content predicted by the rule of mixture for unidirectional composites was 13.8
±1.4 vol%. Optical characterization showed that the fiber distribution was homogeneous and a satisfactory wetting of the fibers
by the matrix was achieved. Using a blower to remove excess matrix powder during processing increased the fiber content to
26.5 ±3.3 vol % (volumetric) or 30.0 ±0.4 vol% (rule of mixture). The tensile strength of the composite parallel to the fiber
direction was 128 ±12 MPa (10 vol% fiber) up to 278 ±48 MPa (26.5 vol% fiber), compared to 20 MPa for the PHB/V matrix. The
Young’s modulus was 5.8 ±0.5 GPa (10 vol% fiber) and reached 11.4 ±0.14 GPa (26.5 vol% fiber), versus 1 GPa for the matrix. 相似文献
147.
Alexander Steinbüchel Henry E. Valentin Andreas Schönebaum 《Journal of Polymers and the Environment》1994,2(2):67-74
Screening of a large number of bacteria revealed several strains, which utilize 1,4-butanediol and/or 4-hydroxybutyric acid (4HB) as a carbon source for growth and for synthesis of polyhydroxyalkanoic acids (PHA) containing 4HB as one constituent among others (mostly 3-hydroxybutyric acid). However, none of the wild-type strains investigated in this study was able to produce a homopolyester consisting solely of 4HB. Only several poly(3-hydroxybutyric acid)-leaky mutants ofAlcaligenes eutrophus strain JMP222 synthesized poly(4HB) homopolyester, which amounted to approximately 10% (w/w) of the cellular dry matter. If the PHA synthase structural gene ofA. eutrophus strain H16 was expressed in these mutants, the amount of poly(4HB) was increased to approximately 30% (w/w). The occurrence of poly(4HB) was demonstrated by gas chromatographic as well as1H and13C nuclear magnetic resonance spectroscopic analysis.Paper presented at the Bio/Environmentally Degradable Polymer Society—Second National Meeting, August 19–21, 1993, Chicago, Illinois. 相似文献
148.
Henry L. Garie Alan McIntosh 《Journal of the American Water Resources Association》1986,22(3):447-455
ABSTRACT: A study of benthic macroinvertebrate community composition was conducted at eight sites along Shabakunk Creek, a small stream in Mercer County, New Jersey, which receives urban runoff. The relationship between changes in substrate composition and the nature of the benthic macroinvertebrate community has been examined. Organisms were collected seasonally from natural substrates in riffles. Attempts to employ artificial substrates for invertebrate collection proved unsuccessful, as the population on the samplers was not representative of that in the stream bed. Number of total benthic macroinvertebrate taxa collected declined from 13 in relatively undeveloped upstream areas to four below heavily developed areas, while population density decreased simultaneously in the same areas. Periphyton samples collected from natural substrates were analyzed for selected heavy metals. Significantly higher heavy metal concentrations are reported from substrates sampled below heavily developed areas, and changes in these values are discussed with regard to changes in benthic macroinvertebrate distribution. 相似文献
149.
Subsequent to modeling of natural attenuation processes to predict contaminant trends and plume dynamics, monitoring data were used to evaluate the effectiveness of natural attenuation at reducing contaminant concentrations in groundwater at seven fuel-contaminated sites. Predicted and observed contaminant trends at seven sites were compared in order to empirically assess the accuracy of some fundamental model input parameters and assumptions. Most of the models developed for the study sites tended to overestimate plume migration distance, source persistence, and/or the time required for the benzene, toluene, ethyl benzene, and xylenes (BTEX) plumes to attenuate. Discrepancies between observed and predicted contaminant trends and plume behavior suggested that the influence of natural attenuation process may not have been accurately simulated. The conservatism of model simulations may be attributed to underestimation of natural source weathering rates, overestimation of the mass of contaminant present in the source area, and/or use of overly conservative first-order solute decay rates. 相似文献
150.
Henry P. Huntington Andrey Zagorsky Bjrn P. Kaltenborn Hyoung Chul Shin Jackie Dawson Maija Lukin Parnuna Egede Dahl Peiqing Guo David N. Thomas 《Ambio》2022,51(2):298
The Arctic Ocean is undergoing rapid change: sea ice is being lost, waters are warming, coastlines are eroding, species are moving into new areas, and more. This paper explores the many ways that a changing Arctic Ocean affects societies in the Arctic and around the world. In the Arctic, Indigenous Peoples are again seeing their food security threatened and cultural continuity in danger of disruption. Resource development is increasing as is interest in tourism and possibilities for trans-Arctic maritime trade, creating new opportunities and also new stresses. Beyond the Arctic, changes in sea ice affect mid-latitude weather, and Arctic economic opportunities may re-shape commodities and transportation markets. Rising interest in the Arctic is also raising geopolitical tensions about the region. What happens next depends in large part on the choices made within and beyond the Arctic concerning global climate change and industrial policies and Arctic ecosystems and cultures. 相似文献