Water samples from Daan Viljoen dam, Avis dam and Goreangab dam were collected and filtered with burlap, cotton and polyester. The water samples were analyzed for the presence of total coliform, Escherichia coli, hete...Water samples from Daan Viljoen dam, Avis dam and Goreangab dam were collected and filtered with burlap, cotton and polyester. The water samples were analyzed for the presence of total coliform, Escherichia coli, heterotrophic plate count (HPC), somatic coliphage, Clostridium perfringens, turbidity and conductivity. The bacteriological analysis was carried out by membrane filtration and pour plate techniques. The water from the three dams was found to contain high levels of microorganisms which indicated that it was not safe for human consumption. Turbidity was improved after filtration. Cotton filtered out the most microorganisms (p < 0.05) in all dams compared with the other two types of cloths.展开更多
The laser induced fluorescence (LIF) spectra from plants give accurate information on the influences of ultraviolet A (UV-A) and ultraviolet B (UV-B) radiation on the growth of maize plants. In this paper, a thorough ...The laser induced fluorescence (LIF) spectra from plants give accurate information on the influences of ultraviolet A (UV-A) and ultraviolet B (UV-B) radiation on the growth of maize plants. In this paper, a thorough LIF study has been done on maize plants grown under controlled conditions. The maize (Zea mays) seeds were planted and exposed to UV-A and UV-B radiation from 0 to10 hours. The decrease in the ratios of peaks of LIF confirm a decrease in the height, diameter of stem, number of leaves in the plants exposed to UV-B and UV-A with the increase in the time of exposure.展开更多
文摘Water samples from Daan Viljoen dam, Avis dam and Goreangab dam were collected and filtered with burlap, cotton and polyester. The water samples were analyzed for the presence of total coliform, Escherichia coli, heterotrophic plate count (HPC), somatic coliphage, Clostridium perfringens, turbidity and conductivity. The bacteriological analysis was carried out by membrane filtration and pour plate techniques. The water from the three dams was found to contain high levels of microorganisms which indicated that it was not safe for human consumption. Turbidity was improved after filtration. Cotton filtered out the most microorganisms (p < 0.05) in all dams compared with the other two types of cloths.
文摘The laser induced fluorescence (LIF) spectra from plants give accurate information on the influences of ultraviolet A (UV-A) and ultraviolet B (UV-B) radiation on the growth of maize plants. In this paper, a thorough LIF study has been done on maize plants grown under controlled conditions. The maize (Zea mays) seeds were planted and exposed to UV-A and UV-B radiation from 0 to10 hours. The decrease in the ratios of peaks of LIF confirm a decrease in the height, diameter of stem, number of leaves in the plants exposed to UV-B and UV-A with the increase in the time of exposure.
