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191.
Book reviews     
Our Stolen Future. How man-made chemicals are threatening our fertility, intelligence and survival. T. Colborn, J. P. Myers & D. Dumanoski, 1996, Boston, Little, Brown, 306 pp. ISBN 0 316 87546, £18.99

Environmental Sociology: a social constructionist perspective. John Hannigan, 1995, London, Routledge, ISBN 0 415 112 559, £12.99

Citizen Science: a study of people, expertise and sustainable development. Alan Irwin, 1995, London, Routledge, ISBN 0 415 130 107, £13.99

The True Costs of Road Transport. David Maddison, David Pearce, Olof Johansson, Edward Calthrop, Todd Litman & Eric Verhoef, 1996, London, Earthscan, 242 pp. ISBN 185 383 2685, £10.95

Car Dependence: a report for the RAC Foundation for Motoring and the Environment. RAC Foundation for Motoring and the Environment, 1995, London, 154 pp. ISBN 086211355 5

Local Sustainability: turning sustainable development into practical action in our communities. Roger Few (Ed.), Leicester Environment City Trust, 1996, Leicester, Environ Trust, 100 pp., £28.00, [Available from: Environ Parkfield, Western Park, Leicester, LE3 6HX, UK]

Successful Environment Management in a Week. Mark Yoxon, 1996, London, Hodder & Stoughton, 96 pp. ISBN 0 340 66374 X, £6.99

Principles of Environmental and Resource Economics. H. Folmer, H. Landis Gabel & H. Opschoor (Eds), 1995, Aldershot, Edward Elgar, 512 pp. ISBN 1 85898 224 3, £85.00

The Contingent Valuation of Environmental Resources: methodological issues and research needs. David Bjornstad & James R. Khan (Eds), 1996, Cheltenham, UK and Brookfield USA, Edward Elgar, ISBN 1 858983215

Towards Sustainability. Peter Martin & Colin Hutchinson, 1996, London, Office for Public Management, £5.45

Conservation and the Consumer: understanding environmental concern. Paul Hackett, 1995, London, Routledge, 229 pp. ISBN 0 415 08096 7, £45.00  相似文献   
192.
Linear low-density polyethylene films were prepared that contained native corn starch (7, 14, or 28%), low or high molecular weight oxidized polyethylene (15%), and a prooxidant mixture (18% POLYCLEAN II) that contains manganese and vegetable oil. For each mixture all components were first mixed at high temperatures in a twin-screw extruder and pelletized. The pellets were cast into films using a single-screw extruder. Oxidized-polyethylene addition did not impair the transparency and thickness of the films and did not reduce the percentage elongation, whereas significant reductions in film mechanical properties were observed. Thermal and photodegradation properties of each film were evaluated by 70°C forced-air oven treatment (20 days), by high-temperature, high-humidity treatment in a steam chamber (20 days), and by exposure to ultraviolet light (365 nm; 4 weeks). Changes in the mechanical properties of the films were determined by an Instron Universal Test Machine; in the carbonyl index, Fourier transform infrared spectroscopy; and in molecular weight, by high-temperature gel-permeation chromatography (HT-GPC). The addition of oxidized polyethylene, especially high molecular weight oxidized polyethylene, and up to 14% starch to the films significantly increased the rate of thermal and photodegradation.Journal Paper No. J-15363 of the Iowa Agriculture and Home Economics Experiment Station, Ames. Project No. 0178 and 2889.  相似文献   
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ABSTRACT: A method to partition the variation in concentrations of water chemistry parameters in a river is described. The approach consists of fitting a family of curves for each chemical parameter. Each curve indicates the response of the parameter to river flow for a particular time period or location. An analysis of covariance is then used to identify statistically significant differences between curves. Such differences result largely from two factors: (1) the discharge of effluents and (2) river flow-concentration relationships. The deviations from the fitted curves indicate month-to-month variations unrelated to river flow that are controlled by factors such as temperature-related seasonal patterns. Underlying statistical assumptions are discussed with respect to water chemistry data. The technique is applied to a data set consisting of monthly samples of 22 water chemistry parameters from the Sulphur River of Texas and Arkansas. Several patterns of response to river flow and to two effluent discharges were revealed.  相似文献   
195.
ABSTRACT: With the advent of standards and criteria for water quality variables, there has been an increasing concern about the changes of these variables over time. Thus, sound statistical methods for determining the presence or absence of trends are needed. A Trend Detection Method is presented that provides: 1) Hypothesis Formulation - statement of the problem to be tested, 2) Data Preparation - selection of water quality variable and data, 3) Data Analysis - exploratory data analysis techniques, and 4) Statistical Tests - tests for detecting trends. The method is utilized in a stepwise fashion and is presented in a nonstatistical manner to allow use by those not well versed in statistical theory. While the emphasis herein is on lakes, the method may be adopted easily to other water bodies.  相似文献   
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197.
Prioritizing the U.S. Department of Energy's (DOE's) targeted R&D program supporting weapons-complex clean-up has been problematic. Considering issues common to all R&D evaluation, linking R&D prioritization to clean-up project prioritization, the latter aligned with institutional goals, offers a pragmatic solution. This method is illustrated with results of a clean-up prioritization model of DOE's Oak Ridge National Laboratory site.  相似文献   
198.
Stormwater discharges from Chollas Creek, a tributary of San Diego Bay, have been shown to be toxic to aquatic life. The primary objective of this study was to provide the linkage between in-channel measurements and potential impairments in the receiving waters of San Diego Bay. This study addressed this objective within the context of four questions: (1) How much area in San Diego Bay is affected by the discharge plume from Chollas Creek during wet-weather conditions?; (2) How much of the wet-weather discharge plume is toxic to marine aquatic life?; (3) How toxic is this area within the wet-weather discharge plume?; and (4) What are the constituent(s) responsible for the observed toxicity in the wet-weather plume? The stormwater plume emanating from Chollas Creek was dynamic, covering areas up to 2.25 km2. Approximately half of the plume was estimated to be toxic to marine life, based upon the results of purple sea urchin (Strongylocentroutus purpuratus) fertilization tests. The area nearest the creek mouth was the most toxic (NOEC = 3 to 12% plume sample), and the toxicity decreased with distance from the creek mouth. The toxicity of plume samples was directly proportional to the magnitude of plume mixing and dilution until, once outside the plume margin, no toxicity was observed. Trace metals, most likely zinc, were responsible for the observed plume toxicity based upon toxicity identification evaluations (TIEs). Zinc was also the constituent identified from in-channel samples of Chollas Creek stormwater using TIEs on the storms sampled in this study, and in storms sampled during the previous storm season.  相似文献   
199.
Long-term monitoring of estuarine nekton has many practical and ecological benefits but efforts are hampered by a lack of standardized sampling procedures. This study provides a rationale for monitoring nekton in shallow (<#60; 1 m), temperate, estuarine habitats and addresses some important issues that arise when developing monitoring protocols. Sampling in seagrass and salt marsh habitats is emphasized due to the susceptibility of each habitat to anthropogenic stress and to the abundant and rich nekton assemblages that each habitat supports. Extensive sampling with quantitative enclosure traps that estimate nekton density is suggested. These gears have a high capture efficiency in most habitats and are small enough (e.g., 1 m2) to permit sampling in specific microhabitats. Other aspects of nekton monitoring are discussed, including spatial and temporal sampling considerations, station selection, sample size estimation, and data collection and analysis. Developing and initiating long-term nekton monitoring programs will help evaluate natural and human-induced changes in estuarine nekton over time and advance our understanding of the interactions between nekton and the dynamic estuarine environment.  相似文献   
200.
A basic investigation of boron in discharged fly ash by coal fuel thermal power plants in several worldwide locations was carried out. Eight kinds of fly ash sample were prepared from eight coal fuel thermal power plants. Two of the fly ash samples were used to examine the relationship between the concentration of boron in fly ash and the particle size. When the particle size of fly ash is smaller, there is a possibility that it will be released into the air and spread over a wide area in the environment. However, it has become apparent that fly ash of smaller particle size has a higher concentration of boron and a higher enrichment factor. In other fly ash samples, the boron contents were examined and leaching tests were carried out. There is acidic fly ash as well as alkaline fly ash that contains larger amounts of acidic or basic salts. On alkaline fly ash, when the concentration of boron bound to Fe-Mn oxide is low; it has become apparent that leaching boron is increased in a solution with lower pH of approximately 4 which is nearly the pH of acid rain.  相似文献   
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