This study was based on the evaluation of the potential effectiveness of Moringa oleifera seeds biomass as a biosorbent in the removal of copper (Cu) in water which was justified by the level of toxicity, environmenta...This study was based on the evaluation of the potential effectiveness of Moringa oleifera seeds biomass as a biosorbent in the removal of copper (Cu) in water which was justified by the level of toxicity, environmental unfriendliness and costly nature of chemical coagulants presently used. Fourier transform infrared (FTIR) analysis was used to identify the Moringa oleifera seeds biomass functional groups present in the adsorption of metal ions and found to be the carboxylic acid and amine functional groups (-COOH and -NH). The effects of contact time, adsorbent dosage, metal ion concentration and pH were studied. The maximum adsorption capacity at pH 5, room temperature and 0.8 g dosage was 70% for Cu(II). The adsorption data fitted better to the Langmuir than the Freundlich models as the sorption capacity (q<sub>m</sub>) of Moringa oleifera seeds biomass for Cu(II) was 3.64 mg/g. The separation factor (R<sub>L</sub>) was within the range of 0 and 1 which showed that the Cu(II) biosorption processes were favourable for Moringa oleifera biosorbent. The results showed that Moringa oleifera seed biomass is an effective adsorbent in the removal of the studied heavy metals in water. The effective pH for the Cu(II) removal was 5.0 as equilibrium was achieved practically in 35 min. The quantitative analysis of defatted Moringa oleifera should be studied in order to have a fair mixing ratio between Moringa oleifera seeds biomass and the adsorbate. There is also the ardent need to work on environmentally friendly disposal of adsorbent after saturation of adsorbent by analyte to avoid secondary pollution.展开更多
The assessment of the impact of road infrastructure in the developing countries using the Namibian case scenario was done based on the contemporary challenges of road use. This study employed a qualitative technique u...The assessment of the impact of road infrastructure in the developing countries using the Namibian case scenario was done based on the contemporary challenges of road use. This study employed a qualitative technique using a sample size of thirty (30) selected by the simple random sampling technique. The use of charts, tables and frequencies were done to explain certain trends in the study. A well-structured, valid and reliable questionnaire instrument was designed for the study based on the following research questions;what are the impacts of road transport on the Namibian environment and what are the possible measures that may be used to reduce environmental impact of road transport on the Namibian environment? Twenty five respondents (83%) agreed that road transfer has drastically improved development and 26 (87%) respondents also accepted that it can improve Namibian economy. Similarly, it has also improved communication and technology greatly according to 27 (90%) respondents. To add more credence to the impact of road transport on the economy, all the 30 (100%) of the respondents agreed that road transport aids mobility within Namibia while 27 (90%) respondents supported the opinion that road transport aids in job search, 3 (10%) disagreed. The result shows that car owners service are potential threats which can affect pollution levels as was supported by 97% to cause environmental pollution as well as 100% when combined with energy consumption. Similarly, all the respondents indicated the potential of increased accident rate from poor road safety. Felling of trees poses great danger (97% response) due to the degradation of the environment. Most respondents (77% and 83%) agreed that road transport can lead to land encroachment and loss of aesthetic and farming. This research has shown that eventually death rate may increase from mere ill-health to from the degraded ecosystem, 24 respondents (80%). So many policies to protect the environment but the practical measures are to encourage impact assessment studies for road projects, land use control and human safety precautions on road use.展开更多
文摘This study was based on the evaluation of the potential effectiveness of Moringa oleifera seeds biomass as a biosorbent in the removal of copper (Cu) in water which was justified by the level of toxicity, environmental unfriendliness and costly nature of chemical coagulants presently used. Fourier transform infrared (FTIR) analysis was used to identify the Moringa oleifera seeds biomass functional groups present in the adsorption of metal ions and found to be the carboxylic acid and amine functional groups (-COOH and -NH). The effects of contact time, adsorbent dosage, metal ion concentration and pH were studied. The maximum adsorption capacity at pH 5, room temperature and 0.8 g dosage was 70% for Cu(II). The adsorption data fitted better to the Langmuir than the Freundlich models as the sorption capacity (q<sub>m</sub>) of Moringa oleifera seeds biomass for Cu(II) was 3.64 mg/g. The separation factor (R<sub>L</sub>) was within the range of 0 and 1 which showed that the Cu(II) biosorption processes were favourable for Moringa oleifera biosorbent. The results showed that Moringa oleifera seed biomass is an effective adsorbent in the removal of the studied heavy metals in water. The effective pH for the Cu(II) removal was 5.0 as equilibrium was achieved practically in 35 min. The quantitative analysis of defatted Moringa oleifera should be studied in order to have a fair mixing ratio between Moringa oleifera seeds biomass and the adsorbate. There is also the ardent need to work on environmentally friendly disposal of adsorbent after saturation of adsorbent by analyte to avoid secondary pollution.
文摘The assessment of the impact of road infrastructure in the developing countries using the Namibian case scenario was done based on the contemporary challenges of road use. This study employed a qualitative technique using a sample size of thirty (30) selected by the simple random sampling technique. The use of charts, tables and frequencies were done to explain certain trends in the study. A well-structured, valid and reliable questionnaire instrument was designed for the study based on the following research questions;what are the impacts of road transport on the Namibian environment and what are the possible measures that may be used to reduce environmental impact of road transport on the Namibian environment? Twenty five respondents (83%) agreed that road transfer has drastically improved development and 26 (87%) respondents also accepted that it can improve Namibian economy. Similarly, it has also improved communication and technology greatly according to 27 (90%) respondents. To add more credence to the impact of road transport on the economy, all the 30 (100%) of the respondents agreed that road transport aids mobility within Namibia while 27 (90%) respondents supported the opinion that road transport aids in job search, 3 (10%) disagreed. The result shows that car owners service are potential threats which can affect pollution levels as was supported by 97% to cause environmental pollution as well as 100% when combined with energy consumption. Similarly, all the respondents indicated the potential of increased accident rate from poor road safety. Felling of trees poses great danger (97% response) due to the degradation of the environment. Most respondents (77% and 83%) agreed that road transport can lead to land encroachment and loss of aesthetic and farming. This research has shown that eventually death rate may increase from mere ill-health to from the degraded ecosystem, 24 respondents (80%). So many policies to protect the environment but the practical measures are to encourage impact assessment studies for road projects, land use control and human safety precautions on road use.
