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Search Results: 1 - 10 of 4696 matches for " Rufus Sha’Ato2 "
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The Role of Paraquat (1,1-dimethyl-4,4-bipyridinium chloride) and Glyphosate (n-phosphonomethyl glycine) in Translocation of Metal Ions to Subsurface Soils.
Rhoda O. Mbuk,Rufus ShaAto2,Nnadozie N. Nkpa
Pakistan Journal of Analytical and Environmental Chemistry , 2009,
Abstract: We investigated the role of paraquat (1,1’-Dimethyl-4,4’-bipyridinium dichloride) and glyphosate (N-(phosphonomethyl) glycine), on the translocation of some metals (K, Mg(II), Mn(II), Fe(II), Pb(II), Cu(II) and Cd(II)) in soil, using a topsoil (Aquic Ustifluvent: USDA Soil Taxonomy, 2000) sampled at the University of Agriculture Makurdi Crop Farm, in Central Nigeria (7o 47’N, 8o 32’E). Employing column leaching experiments with water only on native soil and soil spiked with the metals and different levels of glyphosate or paraquat treatment, leachates were collected and analyzed for their metal contents. Results showed that in the presence of paraquat the transport of Fe(II) and Mn(II) by leaching in the soil was suppressed while that of Cu(II), K and Pb(II) was enhanced. Glyphosate, similarly suppressed Mn(II) and to some extent Fe(II) translocation in the soil; however, it enhanced the mobility of Cd(II), Cu(II), Mg(II), Pb(II) and K under similar treatment. While paraquat seemed to enhance the translocation of Mg(II) at low application rates of the herbicide, glyphosate promoted its transport only at high application rates; there was no evidence that paraquat affected the movement of Cd(II) in the soil. Our results show that the long-term use of these pesticides in the field may result in the depletion of Cu(II), K and Mg(II) in agricultural soils, and that the use of glyphospate may present the additional risk of possible groundwater contamination with Cd(II) and Pb(II).
Alginate Reinforced Chitosan and Starch Beads in Slow Release Formulation of Imazaquin Herbicide—Preparation and Characterization  [PDF]
Lami A. Nnamonu, Rufus ShaAto, Ikenna Onyido
Materials Sciences and Applications (MSA) , 2012, DOI: 10.4236/msa.2012.38081
Abstract: In a bid to make slow release formulations of imazaquin, the herbicide was encapsulated in starch and chitosan beads reinforced with alginate. The beads were characterized using SEM, DSC and FTIR. Two types of formulations were made by extrusion into 0.25 M calcium chloride solution: chitosan/alginate (LNCI) and starch/alginate (LNSI) beads, and the third was by gelatinization of starch at 75?C (LNSI2). Findings showed highly porous spherical beads, the starch/alginate beads bigger and less porous than the chitosan/alginate beads with diameters of 2.53 ± 0.01 and 2.31 ± 0.01 mm; porosity of 57.58% ± 0.2% and 81.28% ± 0.2% and swelling of 34.91% ± 0.2% and 80.35% ± 0.2%, respectively. FTIR revealed a reduction in intensity of the carboxylate peaks of alginate and the peak at 1058 cm?1, present in the FTIR of the matrices, is shifted to lower wave-numbers in the formulations, signifying interactions between the formulation components that make for good slow release. The DSC thermograms of all formulations showed evidence of interaction of imazaquin carboxylate group with the N-atoms of the macromolecules, which is indicative of reduced crystallinity of imazaquin.
Spatial and Temporal Variation in Water Quality of River Benue, Nigeria  [PDF]
Ishaq S. Eneji, Agada P. Onuche, Rufus ShaAto
Journal of Environmental Protection (JEP) , 2012, DOI: 10.4236/jep.2012.328106
Abstract: The study investigates the spatial and temporal variation in water quality parameters at ten different locations along River Benue for twelve consecutive months. In order to explore the spatial variation among different stations and seasonal changes, multivariate analysis of variance (MANOVA) was used to group these on the basis of spatial similarities. MANOVA on season and station shows that there is no significant difference between the stations investigated while there is for the seasons. This could be viewed as a resulting from the narrow spatial sampling interval (12 km at 0.7% total length of River Benue). However, discriminate analysis identified all the parameters to discriminate between the three seasons with 99.2% correct assignations. Two discriminate functions were found and the total variance cumulative was 100% between seasons. The first function explained 64.8% of the total variance between the seasons while the second function explained 35.2%. Total solids (TS) were the highest contributor in discriminate functions 1 and 2. Therefore, discriminate function analysis would enable us to predict the likely season a water sample from metropolitan Makurdi was collected given the values of the water quality parameters. It also enables us to conclude that all the parameters were responsible for significant seasonal variations in River Benue water quality.
Environmentally Friendly Formulations of Trifluralin Based on Alginate Modified Starch  [PDF]
Ikenna Onyido, Rufus ShaAto, Lami A. Nnamonu
Journal of Environmental Protection (JEP) , 2012, DOI: 10.4236/jep.2012.39127
Abstract: In line with global efforts towards sustainable agriculture, the use of starch modified with alginate in the preparation of slow release formulations of the herbicide trifluralin was investigated. Trifluralin was encapsulated in starch-alginate beads, and the resulting slow release formulations (SRFs) characterized using scanning electron microscopy (SEM) and Fourier Transform infrared (FTIR) spectroscopy. Herbicide release from the SRFs was studied in water and compared to release of technical grade trifluralin. Three sets of formulations were made by extrusion into 0.25 M calcium chloride solution: starch/alginate (SSTRF), amylose starch/alginate (ASSTRF) and amylose starch/alginate/groundnut oil (ASTRGNO) beads, and the fourth was from gelatinized starch at 75?C (SSTRF2). The results showed highly porous spherical beads, the amylose/alginate beads bigger and less porous than the starch/alginate beads with diameters of 2.79 ± 0.01 and 2.37 ± 0.01 mm; porosity of 54.67 ± 0.2 and 60.59% ± 0.2% and swelling of 54.09 ± 0.2 and 61.22% ± 0.2%, respectively. All sets of beads exhibited reduced crystallinity of trifluralin. FTIR revealed a shift to lower wavelength of the carbonyl stretching vibrations from 1750 to 1725 cm–1 and a reduction in intensity of the carboxylate peaks of alginate, suggesting interactions between the formulation components that make for good slow release. 96% of technical grade trifluralin (TGTRF) was released into a 50:50 pH 6.5 Buffer/ Methanol aqueous medium in 24 hrs. However, for the starch/TRF formulation, SSTRF, only 9.33% herbicide was released after 24 hrs and 34.94% after 672 hrs (28 days). The amylose starch/TRF formulation released 13.61% herbicide in 24 hrs and 46.95% in 672 hrs, a 12% increase in release of TRF over the starch formulation. Encapsulation in starch produced 65% slow release of TRF and gelatinization achieved 84% retardation. Use of amylose starch as matrix caused 53.15% delay and addition of groundnut oil resulted in 80.87% retardation of TRF release. Encapsulation of TRF in starch/alginate beads is a veritable way of reducing negative environmental effects.
Analysis of Heavy Metals in Human Hair Using Atomic Absorption Spectrometry (AAS)  [PDF]
Onuwa O. Peter, Ishaq S. Eneji, Rufus ShaAto
American Journal of Analytical Chemistry (AJAC) , 2012, DOI: 10.4236/ajac.2012.311102
Abstract: Hair samples of individual were analysed for heavy metals (Cd, Cr, Pb and As) across gender and various occupational distributions by Atomic Absorption Spectrophotometric technique (AAS). The results of replicate analysis shows the following mean concentrations (mg/kg): Cd = 27.8 ± 8.0, Cr = 2.70 ± 0.7, Pb = 73.8 ± 42.3 and As = 222 ± 34.1. The coefficients of variation for the total distribution is; Cd = 28%, Cr = 26%, Pb = 57% and As = 15%. The distribution of the metals follows the series in decreasing order of As > Pb > Cd > Cr, while their coefficients of variation is in the order of Pb > Cd >Cr > As. The result shows the presence of all the metals in relatively large amounts with As having the highest concentration between the two genders. The difference between male and female concentration could be due to individual differences in exposure to heavy metal load as a result of habitual or environmental factors.
Concentration of Heavy Metals in Respirable Dust in Jos Metropolitan Area, Nigeria  [PDF]
Godwin M. Mafuyai, Ishaq S. Eneji, Rufus ShaAto
Open Journal of Air Pollution (OJAP) , 2014, DOI: 10.4236/ojap.2014.31002
Abstract:

The concentration of respirable dust at seven sampling stations in Jos metropolitan area, was measured weekly for three consecutive months (October 2012 to December 2012). Characterization of the dust particles shows that the concentration of fine dust (<2.5 μm) ranged from 55.0 - 124.9 μg/m3 while the coarse dust (2.5 - 10 μm) varied from 20.0 - 124.4 μg/m3. FAAS analysis of the respirable dust shows that the concentrations of heavy metals ranged from 0.121 - 0.832 mg/kg Pb, 0.019 - 0.111 mg/kg Cr, 0.171 - 1.081 mg/kg Fe, 0.002 - 0.056 mg/kg Mn, 0.002 - 0.438 mg/kg Cd, 0.696 -

Analysis of Selenium Content in Root and Tuber Plants in Central Nigeria  [PDF]
Saidu Zarmai, Ishaq S. Eneji, Rufus ShaAto
American Journal of Analytical Chemistry (AJAC) , 2013, DOI: 10.4236/ajac.2013.412089
Abstract:

Some common staple roots and tubers (cassava, yam, sweet potato and yellow yam) were analyzed for selenium content level using hydride generation—atomic absorption spectrophotometry (HG-ASS) technique. Results for duplicate analysis revealed that sweet potato has the highest mean selenium content (19.2 ± 5.20 μg/kg), followed by yellow yam (18.3 ± 6.97 μg/kg), then yam (13.6 ± 7.12 μg/kg) and cassava the least (13.0 ± 5.84 μg/kg). In comparing our results with the literature values, most of the results obtained in this work such as <1.00, 1.09, 1.91, 2.35 and 11.0 μg/kg were lower while a few others like 52.6, 54.2, 72.3 and 81.8 μg/kg were higher than literature values. The variations could be due to the type of species/variety, geographical location, total selenium concentration in the soil and its bioavailability. In view of the importance of Se to human health and considering the levels found in the staples investigated, we recommend that sweet potato be popularized as a staple, much more than cassava as it is now the case in Central Nigeria.

Analysis of Heavy Metals in Human Scalp Hair Using Energy Dispersive X-Ray Fluorescence Technique  [PDF]
Peter O. Onuwa, Lami A. Nnamonu, Ishaq S. Eneji, Rufus ShaAto
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2012, DOI: 10.4236/jasmi.2012.24029
Abstract: Analysis of six heavy metals (Cr, Mn, Ni, Cu, Zn and Mo) in human scalp hair was carried out among various occupational distributions to ascertain their heavy metal burden, using energy dispersive x-ray fluorescence technique (ED-XRF). The result of the analysis shows that mean concentrations (mg/kg) of heavy metals obtained were as follows: Cr = 17.1 ± 12.7; Mn = 3.11 ± 0.50; Ni = 11.3 ± 9.3; Zn = 451 ± 128; Cu = 83.3 ± 35.8 and Mo is 9.16 ± 9.1.While the mean concentrations of Cr, Cu, and Mo were higher in the females, that of Mn, Ni and Zn were more in the males. Statistical analysis of the results for both genders at 0.05 probably shows significant difference for Ni, Zn and Mo while Cr, Mn and Cu showed no significant difference. The relationships between age, body mass, height, and heavy metal concentrations were also investigated. Statistical analysis of the results indicates that there was no correlation between the body mass (R2 ≤ 0.048), height (R2 ≤ 0.002) and heavy metal concentration in hair. Zn showed the highest deviation among other elements in the individual samples for both genders which reflect the individual variation in the concentration of Zn.
Kinetics of Sorption of Pendimethalin on Soil Samples Obtained from the Banks of Rivers Katsina-Ala and Benue, Central Nigeria  [PDF]
Justin Kpagh, Rufus ShaAto, Raymond A. Wuana, Terrumun A. Tor-Anyiin
Journal of Geoscience and Environment Protection (GEP) , 2016, DOI: 10.4236/gep.2016.41004
Abstract: Kinetics of the sorption of the herbicide, pendimethalin (3,4-Dimethyl-2,6-dinitro-N-pentan-3-yl-aniline) on four soil samples obtained from the banks of Rivers Benue and Katsina-Ala, in Central Nigeria was studied by contacting 5.0 g soil samples with 100 mL 7 × 10-6 M herbicide solution. The sorption was monitored by following the herbicide concentration in the aqueous phase spectrophotometrically at one hour intervals for 5 hours (at 25°C, 35°C, 45°C, 55°C and 65°C, respectively). Pseudo-first order kinetics treatment of the data showed that sorption rates as well as the accompanying activation energies were low, indicating that physical adsorption is the operative mechanism for its retention in the soils and that the herbicide tended to reside more in the aqueous phase, which raised its potential to contaminate natural water systems, when applied on the field.
Bioaccumulation of Heavy Metals in Fish (Tilapia Zilli and Clarias Gariepinus) Organs from River Benue, North – Central Nigeria
Ishaq S. Eneji,Rufus ShaAto,P. A. Annune
Pakistan Journal of Analytical and Environmental Chemistry , 2011,
Abstract: Heavy metals concentrations were determined in fish organs of Tilapia zilli and Clarias gariepinus from River Benue along Makurdi metropolis using atomic absorption spectrophotometer. The results indicated that Tilapia zilli gills contained the highest concentration (52.2%) of all the detected heavy metals, followed by the intestine (26.3%), while the muscle tissues appeared to be the least preferred site for the bioaccumulation of metals as the lowest metal concentration (21.5%) were detected in this tissue. Similarly, the Clarias gariepinus gills contained the highest concentration (40.3%) of all the detected heavy metals, followed by the intestine (31.6%), while the muscle tissue (28.1%) was the lowest. The trend of heavy metals concentration can be represented as: Cr > Zn > Cu > Fe > Mn > Cd > Pb for Tilapia zilli, while that of Clarias gariepinus was Cr > Zn > Fe > Cu > Mn > Cd > Pb. Tilapia zilli showed high bioaccumulation factors of 244, 229 and 178 for Cr, Zn and Cu, respectively. Claria gariepinus showed 232, 226 and 151 for Cr, Zn and Fe, respectively. This suggests that the fish samples could be used to monitor Cr and Zn pollution levels in the River Benue.
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