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Interaction of herbicides and soil microorganisms
1971
The introduction of microorganisms with specific degradative capacities into the soil was shown to be a possible means of ridding the soil of contaminating chemicals. An investigation of the interactions of soil microorganisms and several groups of herbicidal compounds, primarily chlorinated derivatives, was made. In pure culture and in soils the addition of 2,3,5,6-tetrachloroterephthalate (DCPA) had little effect upon bacterial growth, and several microorganisms appeared to use the herbicide as a carbon source. The encouragement of the soil microflora by the addition of nutrient broths resulted in a reduction of toxicity to plants of a number of herbicides. Isopropyl N-phenylcarbamate (IPC) degrading organisms, when added to soil, accelerated the degradation of IPC and related compounds. A membrane 'biologicalilter' device for reducing waterborne biodegradable pollutants was also demonstrated using these organisms.
显示更多 [+] 显示较少 [-]Feasibility of treating wastewater by distillation
1971
Sullivan, James | Singley, Edward
Inorganic sulfur oxidation by iron-oxidizing bacteria
1971
Lundgren, Donald G. (Donald George)
Phosphorus removal and disposal from municipal wastewater
1971
Connell, Cecil H. (Cecil Hardee)
State-of-art, sugarbeet processing waste treatment
1971
Fischer, James A. | Hungerford, Edward H.
Environmental pollution by fluorides in Flathead National Forest and Glacier National Park
1971
Carlson, Clinton E. | Dewey, Jerald E.
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.
显示更多 [+] 显示较少 [-]Characteristics of wastes from southwestern cattle feedlots
1971
Research was conducted on experimental feedlots in Lubbock, Texas, to determine the characteristics of wastes from Southwestern cattle feedlots. The feedlots were generally operated in a manner conforming to normal commercial practice in the area. They were provided with collection pits that allowed the quantity of runoff to be measured accurately. Samples of runoff were collected routinely both during rainstorms and from the collection pits. Manure samples were also collected routinely for analysis. The quantity of runoff per unit area of concrete-surfaced lots is substantially greater than the quantity per unit area of dirt-surfaced lots. Concentrations of pollutants in concrete-lot runoff are substantially higher than corresponding concentrations in runoff from dirt-surfaced lots. Agronomic studies indicate that runoff can be used for irrigation of crops, but extreme caution is required in the application of runoff to crops to prevent damage to them.
显示更多 [+] 显示较少 [-]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)