Amount Of Tailings Research Articles

Biotic and abiotic characteristics of ecosystems on acid metalliferous mine tailings near Sudbury, Ontario

INCO Ltd., a large mining company near Sudbury, Ont., deposits vast amounts of tailings on its property. These tailings contain elevated levels of Cu, Ni, and sulphides, and to curtail dust and acid drainage, INCO has undertaken a long-term project to cover its tailings with vegetation. Yearly amelioration of fresh tailings with limestone and fertilizer, followed by seeding with various grasses and herbs, transplanted conifers, and the later colonization of volunteer species of plants from adjoining forests, has resulted in the formation of ecosystems of varying age and complexity. To assess the long-term effectiveness of INCO's vegetation techniques, we studied floral diversity, attributes of developing soils, and the accumulation of Cu and Ni in various plant species growing on tailings at different stages of development. Habitat disturbance by tailings deposition, and its subsequent floral recolonizaton, is an example of "anthropogenic succession." Tailings that do not receive amelioration in the form ...

Oil sands tailings sludge solidification and bitumen recovery

ABSTRACT Canada is a forerunner in the development of oil sands mining and processing technology. At present two commercial plants, both of them surface mining operations are producing approximately 200,000 of syncrude per day. At both of these plants a hot water separation process is used. The vast amounts of tailings, consisting of bitumen, sand, fines and water, generated from the hot water extraction process while recovering bitumen during surface mining operation, must be stored within gigantic man-made reservoirs created by constructing high dykes or dams. In this study, the potential of lime addition for stabilization of the sludge and recovery of bitumen has been investigated. Results of study indicate that more than 50 percent water as well as the bitumen can be recovered from sludge by centrifuging alone. With lapse of time, lime addition causes solidification of sludge as reflected by strength increase of treated and compacted sludge. The implication of this investigation is that bitumen recove...

Effect of a butter-rich diet on murine frostbite.

A simple reproducible, humane model for producing frostbite in rodents is desirable. We have developed such a model and have investigated the effects of a butter-rich diet on severe cold injury. Mice (25 +/- 2 g) were randomly divided into two groups (n = 10). One group was given a standard rodent diet and the other group a butter-enriched (25%) rodent diet for 1 month. Under pentobarbital sodium anesthesia the mice were placed in a plastic funnel with the stem removed so that the entire tail protruded. The tails were submerged in a freezing solution (-18 degrees C) for 8 min. The mice received no further treatment. Tail lengths were measured 2 weeks after freezing to determine the amount of tail surviving from cold injury after autoamputation. Mean tail lengths (cm +/- SD) for the two groups were as follows: butter-rich diet, 4.3 +/- 1.8; standard diet, 7.3 +/- 2.0 (P less than 0.002). A high saturated-fat diet has a deleterious effect in murine frostbite. This simple model can be employed to test various modalities in the treatment of frostbite.

Bacteriophage P22 tail protein gene expression.

We have found that mutations which block bacteriophage P22 head assembly at or before the DNA packaging stage (1-, 2-, 3-, 5-, and 8-) cause up to a 20-fold increase in the amount of tail (gene 9) protein made during infection. This correlation seems strong enough to warrant consideration of a control mechanism in which the failure to package DNA per se causes a large increase in the synthesis of tail protein. Our results indicate that one of the repressors required for maintenance of lysogeny, the mnt gene product, may be partially responsible for this phenomenon.

The relation of the amount of tail regenerated to the amount removed in tadpoles ofRana clamitans

The relation of the amount of tail regenerated to the amount removed in tadpoles ofRana clamitans