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Результаты 141-150 из 207
Nuclear techniques in environmental pollution
1971
Water quality control through flow augmentation
1971
Baker, David B. | Kramer, Jack W.
Nitrate removal from wastewaters by ion exchange
1971
Grinstead, Robert R. | Jones, Kenneth C.
Environmental control in the organic and petrochemical industries, 1971
1971
Jones, H. R. (Harold R)
Sampling of glacial snow for pesticide analysis
1971
Stengle, Thomas R. | Lichtenberg, James J. | Houston, Charles S.
Snow samples were taken from the plateau glacier of Mt. Logan, Y.T., Canada during an investigation intent on demonstrating the feasibility of taking such samples from high altitude snowfields for pesticide analysis and developing sampling techniques devoid of contamination. Samples were also taken at a depth of 15 m to determine whether DDT concentration varied with the age of the snow. Pesticide analyses were performed using vapor phase chromatographic techniques. DDT was not detected within the limit of detectability (5 ng/l). Over half the samples were contaminated with PCB's which raised the detectability limit to 10-50 ng/1. The PCB contamination is believed to have come from the sampling auger, as an analysis of rinsings from it seemed to confirm. A sample taken from a depth of 1.5-2.5 m was acidified with distilled nitric acid, when thawed, and analyzed for 19 elements simultaleously using a direct reading emission spectrometer. Four elements were detected: boron at 4 ng/ml, cadmium at 9 ng/ml, chromium at 2 ng/ml, and iron at 47 ng/ml. The high levels of cadmium and especially iron suggest contamination from the alloy steels of the auger.
Показать больше [+] Меньше [-]Phosphorus removal and disposal from municipal wastewater
1971
Connell, Cecil H. (Cecil Hardee)
Environmental pollution by fluorides in Flathead National Forest and Glacier National Park
1971
Carlson, Clinton E. | Dewey, Jerald E.
State-of-art, sugarbeet processing waste treatment
1971
Fischer, James A. | Hungerford, Edward H.
Inorganic sulfur oxidation by iron-oxidizing bacteria
1971
Lundgren, Donald G. (Donald George)
Multi-system biological treatment of bleached kraft effluents
1971
