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Air pollution
1998
Wark, Kenneth | Warner, Cecil Francis | Davis, Wayne T.
Indoor pollution
1998
Miller, E. Willard (Eugene Willard) | Miller, Ruby M.
Discusses the health hazards of indoor air contaminants and includes information on their sources, the illnesses they can cause, the ways of controlling them, and other related topics.
Показать больше [+] Меньше [-]Agricultural pesticide residues in oysters and water from two Chesapeake Bay tributaries
1998
Lehotay, S.J. | Harman-Fetcho, J.A. | McConnell, L.L.
Little is known of the impact of agricultural activity on oysters in Chesapeake Bay tributaries. As a preliminary assessment of pesticide residues in oyster tissues, this study monitored more than 60 pesticides in oysters and overlying water in two tributaries of the Chesapeake Bay. Paired water and oyster samples were collected throughout 1997 from the Patuxent and Choptank Rivers which discharge into opposite shores of the Chesapeake Bay in Maryland. In water, herbicides such as atrazine, simazine, cyanazine, and metolachlor were present throughout the year with individual water concentrations peaking as high as 430 ng/1 in the late spring and summer and subsiding in the fall. These herbicides were not detected in the oysters even when concentrations were highest in the water. Another herbicide, trifluralin, was detected throughout the year at concentrations of less than 0.6 ng/1 and 0.4 ng/g (wet weight) in water and oyster samples, respectively. Several insecticides, such as endosulfans I and II, endosulfan sulfate, chlorpyrifos, α- and γ-HCH, p,p'-DDE, o,p'-DDT, trans-nonachlor, and trans-chlordane were also measured in both oysters and water at low concentrations.
Показать больше [+] Меньше [-]Environmental pollution and control
1998
Peirce, J. Jeffrey | Weiner, Ruth F. | Vesilind, P. Aarne
In revising this book, the authors have attempted to reflect the evolving nature of environmental sciences and engineering. They present the more important aspects of environmental engineering, science and technology in an organized manner and for a non-engineering readership.
Показать больше [+] Меньше [-]Integrated pollution control | Umweltschutztechnik. English
1998
Förstner, Ulrich
Sustainable development and pollution control are the key factors in the development of strategies for the solution of environmental problems. This book offers an integrated treatment of all aspects of environmental protection and remediation. The presentation encompasses physical and chemical fundamentals, technological approaches as well as ecological, economic, and ethical aspects. The discussion of regulatory issues includes a comparison of environmental legislation in the US, Japan, and Europe. The book addresses students as a comprehensive text and serves as a handy reference for environmental professionals in industry, consulting services, administration, and environmental agencies and associations.
Показать больше [+] Меньше [-]Effects of Alkalinity and External Sulphate and Phosphorus Load on Water Chemistry in Enclosures in an Eutrophic Shallow Lake
1998
Bellemakers, Martijn J. S. | Maessen, Mario
As a result of changes in hydrology, the former mesotrophic, shallow lake Naardermeer, has been eutrophicated during the last decades. To compensate for shortage of water, eutrophicated water with different chemical characteristics has been supplied. In order to determine the effects of alkalinity, acidity and external sulphate and phosphorus load on eutrophication processes, developments in water chemistry have been studied in enclosures. A decrease of the phosphorus load of the lake did not improve water quality on the short term. This observation was confirmed by this enclosure experiment. Reduction of alkalinity did improve water quality, particularly by reductions of turbidity and chlorophyll-a content. The significant increase in sulphate load in the water layer led to deterioriation of the water quality and an increased biomass of sessile algae by internal eutrophication, probably as a result of increased sulphate reduction in the sediment. Therefore, it seems that lowering of sulphate concentrations in the inlet water after the removal of phosphorus is necessary to improve the water chemistry. The best option, however, is to restore the former hydrological conditions after which the system will be fed only by seepage of groundwater poor in nutrients and sulphate.
Показать больше [+] Меньше [-]Studies of Soils, Soil Water and Stream Water at a Small Catchment near Guiyang, China
1998
Larssen, Thorjørn | Jiling, Xiong | Vogt, Rolf D. | Seip, Hans Martin | Bohan, Liao | Dianwu, Zhao
Acid deposition is considered to be a major environmental problem in China, but information about effects on soils and waters is scarce. To contribute to increased knowledge about the problem a small catchment (about 7 ha) in the outskirts of Guiyang, the provincial capital of Guizhou in south-western China, was instrumented for collection of precipitation, throughfall, soil water and stream water. In addition soil samples have been collected and analyzed for key properties. Median pH in the precipitation is 4.40 (quartiles: 4.19 and 4.77) and the median sulfate concentration 228 µeq/L (quartiles: 147 and 334 µeq/L). The dry deposition of both SO₂ and alkaline dust is considerable. The sum of wet deposition of sulfate and dry deposition of SO₂ has been estimated to about 8.5 gSm⁻²yr⁻¹. The total S-deposition may be somewhat higher due to dry deposition of sulfate and occult deposition. In soil water, SO₄ ²⁻ is the major anion, generally ranging from 300 to 2500 µeq/L in the different plots. Calcium is an important cation, but there is also a considerable contribution of aluminum from the soil. In some of the plots the concentrations of inorganic monomeric aluminum (Ali) are typically between 200 and 400 µm. Potential harmful levels of aluminum and/or high Ali/(Ca²⁺ + Mg²⁺) molar ratios occur in the catchment, but damages to vegetation have not yet been reported. In most cases exchangeable aluminum accounts for between 75 and 95% of the total effective cation exchange capacity (CECE) in the mineral soils. The aluminum chemistry cannot easily be explained by conventional models as the Gaines-Thomas ion-exchange equation or equilibrium with an Al(OH)₃ mineral phase. The stream water is generally less acidic and has considerably lower concentrations of aluminum than the soil water, even though quite acid events have been observed (pH < 4.4). The median pH values are 4.9 and 5.0 in the two first order streams and 6.3 in the dam at the lower boarder of the catchment.
Показать больше [+] Меньше [-]Water supply and pollution control
1998
Viessman, Warren | Hammer, Mark J.
Resource added for the Environmental Engineering Waste and Water Technology program 105062.
Показать больше [+] Меньше [-]Multitracer Study on Absorption of Radionuclides in Atmosphere-Plant Model System
1998
Shinonaga, Taeko | Ambe, Shizuko
The absorption of atmospheric radionuclides by soybean plants was experimentally studied using a radioactive multitracer consisting of radionuclides of Sc, Mn, Co, As, Se, Rb, Sr, Y, Eu, Gd, Yb, Hf, Re, and Ir. The soybean plants were cultivated in soil under no-rain conditions in a box containing air in which multitracer-absorbed cellulose particles were dispersed. The soil was covered with plastic film. After about one-month cultivation, the plants were harvested and washed with dilute HCl solution. The leaves, stems, and beans were subjected to γ-ray measurement. The radionuclides of As, Se, and Re were accumulated in the leaves, and those of Co, Se, and Rb were accumulated in the beans. Among them Se was accumulated to a large extent in the leaves and in the beans. Small amounts of the radionuclides of Co, Se, Rb and Re were found in the roots. Little absorption of these radionuclides into the soil occurred. These results indicate that various radionuclides in the atmosphere were absorbed through the soybean leaves and then transported to the seeds. These findings must be taken into consideration for a complete understanding of the system of uptake of radionuclides by the soybean plant.
Показать больше [+] Меньше [-]Biological Elimination of Volatile Organic Compounds from Waste Gases in a Biofilter
1998
Wu, G. | Chabot, J. C. | Caron, J. J. | Heitz, M.
A great deal of research has been directed towards the problem of reduction and control of volatile organic compounds (VOCs). The aim of this research is to find a process that is both efficient and inexpensive in comparison with traditional air treatment technologies.Our biofilter (one stage system, 2 m in height) is an aerobic system for waste gases containing VOCs using the degradation properties of microbial flora (assorted cultures of Bacillus, Micrococcus, Acinetobacter and yeast). In this process, polluted gas diffuses across a filter bed into which a microbial culture has previously been introduced. Peat is the medium of choice for inoculation with microorganisms because of its adsorption and absorption properties, ability to retain moisture, and buffering capacity. Furthermore, the peat utilized is spherical in shape; thus, it is possible to avoid problems related to compacting.The objective of this study was to eliminate VOCs emitted from a rotogravure process. We were able to achieve promising results from biofiltration of two types of VOCs (a mixed solvent containing isopropyl acetate and 1-nitropropane, and the solvent: 1-nitropropane). The results obtained indicate that the elimination of nitropropane and the mixed solvent in the biofilter are considered to follow zero-order kinetics with reaction rate limitation and diffusion rate limitation, respectively.
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