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  • ItemOpen Access
    Public participation in solid waste management practices within Owerri Urban of Imo State, Nigeria
    (U. P., 2016) Nkwoada, Amarachi; Alisa, Christopher; Duru, Ijeoma
    Municipal waste disposal have reached a crucial point in major urban areas in Nigeria especially Owerri urban and householder’s readiness to participate in waste management are still declining moreover the problems of indiscriminate dumping of refuse at central places and open dumping and burning at private residents continue to persist. A structured questionnaire was provided to residents of Owerri urban areas addressing lack of knowledge and attitude as a factor in waste recycling, methods of waste disposal, participation and practice using SCHOM analysis that identified 24 active waste dump/disposal sites. ANOVA at 0.95% value of F calculated was 0.25 and less than the value of F critical at value of 4.25 which shows that the burning and burying of waste was unaffected by usage of bins within any location but rather a habit acquired over the years. Also F calculated in column of ANOVA was less than F critical and showed that different zones exhibit different disposal habits and their levels of participation are affected by levels of quality of surrounding environment, popular trend, sex, age and income. SCHOM participants revealed a trend in volume of waste generated among householders to be Metals
  • ItemOpen Access
    Evaluation of organic and inorganic pollution indicators in a homeland river
    (International Science Community Association, 2020) Akagha, C. I.; Nkwoada, A. U.; Nnadozie, C. F.
    The objective of this study was to develop a biannual database for selected organic and inorganic river pollution indicators. The DO, BOD and COD levels alongside TSS and TDS concentrations were determined using standard protocols. The compiled database consisted of 5 aforementionedduring the biannual study generating over 60 data per specific parameter with 60 data per variable, per season per annum. April/May recorded highest values of TSS at "UT" sampling pointvalues of TSS at 60.38 mg/L exceeding the APHA, EU, EPA and FME discharge limits, except WHO standards. Highest TDS (68.20 mg/L) was in 2014 (Oct/NOV) at "DS" sampling point which exceeded FME and EPA pebelow WHO, EU and APHA standards. Observation shows that 2015 was an active DO year much more than 2014 and DO decreased significantly as water flows downstream. Moreover, the highest COD concentration was 290 mg/L at "NB" sampling point during Oct/Nov that was high but below APHA standard. However, the BOD levels between the seasons showed no seasonal variation within each year, which might be due to active and regular discharge of organic pollutants from abattoir source throughout the biannual study. ANOVA analyses showed that BOD and TSS data were statistically more accurate than other parameters. In conclusion, the river is unsafe, unclean and unacceptable for public consumption, recreation, sensitive fish habitation, requires pollution and preventive measures.
  • ItemOpen Access
    Spatio-temporal study of criteria pollutants in Nigerian city
    (U. P., 2020-06-29) Anyika, L. C.; Alisa, C. O.; Nkwoada, A. U.; Opara, A. I.; Ejike, E. N.
    Aims: An investigation of characteristic long term air pollutants known for temporal and spatial behaviors was conducted due to increased pollution scenarios in Nigerian cities as a result of deprived environmental enforcement of statutory obligations. Study Design: One of the worlds’ most polluted cities (Onitsha lower basin) in Nigeria was selected for spatio-temporal study of three criteria pollutants combined with GIS and MATLAB alongside associated meteorological conditions during harmattan. Methodology: 72-hourly analyses of the nine different locations having 4 sampling sites and 500 meters apart were done from December to February which generated over 19, 440 experimental data per quarter of each annual study. Results: Upper Iweka/Nitel area recorded the highest concentration of SO2 pollutant at (94.2 µg/m3) due to longer residence times and low wind mixing height. Borromeo hospital showed the least active NO2 region but converges at points 1 due to North-east wind dissimilar to sampling points 1 having the lowest PM10 distribution. Measured temperature parameter correlates inversely with relative humidity and precipitation. The GIS spatial representation corresponded to temporal variability of gaseous and particulate pollutants. Conclusion: All sampled areas had AQI above 50; hence the study identified SO2, NO2, and PM10 as Primary pollutants of Onitsha lower basin.
  • ItemOpen Access
    The role and economics of nano-graphene functionalization in oil industry improvement
    (U. P., 2018-03-06) Nkwoada, Amarachi U.; Amakom, Chijioke M.; Oguzie, Emeka E.
    The toxic pollutants released from oil and gas activities typically takes years of clean-up and reclamation. Hence, creating the need for new nano-materials that can function as adsorbents, filter membranes, and coating materials, which offer a molecular level of control in separating relevant pollutant mixtures. The advances in graphene-family and its derivatives has proven its effectiveness to gradually replace conventional filter membranes, coatings, adsorbents, sensors for nanomaterials applications in the oilfield. The functionalization of graphene and graphene oxide has enabled such nano-graphene-composite materials to be tailored to meet the new development of coatings, adsorbents, filter membranes and sensors for oil and gas applications with high scalability potentials
  • ItemOpen Access
    Establishing risk assessment from reclaimed Nekede Mechanic Village Owerri, Nigeria
    (U. P., 2018-09-14) Nkwoada, A. U.; Alisa, C. O.; Amakom, C. M.; Enenebeaku, C. K.
    The current resettlement of Nekede Auto-Mechanic village by Imo State government of Nigeria created a sparse piece of land awaiting government utilization. Risk assessment was carried out on the land using existing boreholes and soil to determine land utilization potential. Analysis of the physicochemical water parameters showed that there was no contamination of boreholes. The high value of COD correlated with the high levels of Fe in soil and water samples. Heavy metals concentrations showed that Fe was very much present in the soil while Pb, Cd and Cu had reduced concentrations. Risk assessment for the soil samples showed that Fe had the highest mean and median value. The highest mean value for water was Cu metal. Highest variance value was Cu in soil while Pb had the lowest value in water. Hazard quotient of water samples showed that hazards existed for Cd, Cu and Pb but at a moderate level for Fe. Estimated daily/weekly water intake values were all below WHO/FAO standards. The soil enrichment factor showed no enrichment for Pb, minimal enrichment for Cd, moderate enrichment for Cu and significant contamination for Fe. Ecological risk assessments for the heavy metals were at low ecological risk. Potential ecological index depicts Fe and Cd at a considerable level of ecological risk. Likewise, contaminants existed at the nearby Otamiri river due to dredging and nearby waste dumps. The anthropogenic activity at the Otamiri river posed a serious environmental concern if not controlled and reclaimed. Hence, the reclamation of Nekede auto mechanic village will not be suitable for agricultural or recreational purposes.
  • ItemOpen Access
    GIS and MATLAB modeling of criteria pollutants: A study of Lower Onitsha Basin during rains
    (Journal BiNET Scientifc Publishing, 2018-10-14) Anyika, L. C.; Alisa, C. O.; Nkwoada, A. U.; Opara, A. I.; Ejike, E. N.; Onuoha, G. N.
    The study of air pollutants SO2, NO2 and PM10 in lower Onitsha basin, a densely populated city was performed using GPS and Matlab modeling. The pollutants were studied in nine specific locations for 3 months of rains over 3 consecutive years with each georeferenced. The Matlab pollution model was generated by integrating the spatial database and measured pollution attributes database using a polynomial expression. SO2 highest concentration (141 µg/m3) peaked in Upper Iweka at sampling point 1 before dispersing to lower concentrated regions in Awada and Resthouse. NO2 peaked at 207 µg/m3 in Upper Iweka at sampling point 3 and driven by wind towards Borromeo area to very low concentration of 38 ug/m3. The PM10 peaked in Upper Iweka (180 µg/m3) and driven by rains towards Borromeo before increasing again in concentration levels at Awada. The AQI showed that SO2 pollutants had acceptable air quality at all sampling points while NO2 and PM10 air quality affected sensitive groups. SO2 concentration levels exceeded the National air quality standard in Nigeria (NAQS) while NO2 and PM10 were below the NAQS standard. The GIS plot showed that 3 metrological forces were driving pollutants from Upper Iweka and Awada to other sampling areas in the order of SO2> NO2> PM10. The Matlab wind speed plot showed that there was an upward wind in upper Iweka driving the pollutants towards dispersal at some other region. Thus, Upper Iweka is an active point source pollution area and dispersed to Borromeo and Awada by scavenging rains under prevailing wind speed, wind direction and humidity. Hence calls for improved monitoring and regulation to address poll.
  • ItemOpen Access
    Radionuclide concentration: The coal ash effect
    (Academic Journals, 2018) Amakom, M. Chijioke; Orji, E. Chikwendu; Iroegbu, Chinedu; Eke, C. Benedict; Nkwoada, U. Amarachi; Madu, D. Afam; Ugochuwu, G. Kosisochukwu; Oforma, J. Tochukwu
    Radionuclide concentrations in coal ash, soil mixed with coal ash and soil were determined using the gamma spectroscopic method. The average activity concentrations of 226Ra, 232Th, and 40K in coal ash samples were found as 35.0, 5.8, and 109.4 Bq/kg, respectively. The average activity concentrations of 226Ra, 232Th and 40K in soil mixed with coal ash samples varied from 21.2 to 30.8, 48.6 to 82.7, and 162.5 to 180.1 Bq/kg, respectively. The activity concentrations of radionuclides from the non-mixed soil area, which serves as a control to this study ranged from 123.95 to 128.82, 16.33 to 18.38, and 46.63 to 50.30 Bq/kg, respectively for radionuclides 40K, 226Ra, and 232Th, respectively. From the radiological calculations, it was found that the use of coal ash as a soil additive contributed slightly to the radionuclide concentrations of the area under study.
  • ItemOpen Access
    Radionuclide depth profile baseline and radiation hazard indices of the reclaimed old Nekede Mechanic Village, Owerri, Imo State, Nigeria
    (U. P., 2021-02-06) Amakom, Chijioke M.; Nkwoada, A. U.; Nwaogbo, Chidiebere I.; Iheonu, Nneka O.
    Radionuclide concentration in soil samples collected at the old Nekede auto-mechanic village in Owerri were determined using gamma spectroscopy. A total of 15 soil samples were collected at depths of 10-cm, 20-cm and 30-cm at 5 different sites respectively. From the results, the mean activity concentrations of 40K, 226Ra, and 232Th were 132.66±5.61 Bq/Kg, 26.38±3.88 Bq/Kg, and 73.24±4.91 Bq/Kg respectively for samples collected at 10cm depth. At 20cm depth the mean values obtained were 111.95±6.51 Bq/Kg, 32.63±3.48 Bq/Kg, and 89.76±5.20 Bq/Kg for 40K, 226Ra, and 232Th respectively, while 102.88±4.62 Bq/Kg, 30.03±2.77 Bq/Kg, and 76.08±6.65 Bq/Kg were obtained at the 30 cm depth for 40K, 226Ra, and 232Th respectively. The calculated absorbed dose rate and annual effective dose have an average value of 66.6687 nGyh-1 and 0.0912 mSv.y-1 . The 10cm depth presented the lowest dose rate and annual effective dose rate with values of 61.9564 nGyh-1 and 0.0847 mSv.y-1 respectively. While the highest values were obtained at 30cm depth with values of 64.0913 nGyh-1 and 0.0876 mSv.y-1 respectively. The value of the annual effective dose lies within the world average value of 1.0 mSvy-1annual effective dose equivalent rate. The hazard indices corresponding to the collected samples was also estimated to have a mean value of 0.142, which is below the ecommended world average.
  • ItemOpen Access
    Novel non-parametric assessment of heavy metals in coated card wastes
    (U. P., 2017-11-09) Nwoko, C. I. A.; Nkwoada, A. U.; Njoku, P. C.; Obichini, A.
    Non-parametric tests were applied for the first time to coated mobile card waste in order to determine the correlation within risk assessment and instrumentation. The AAS concentrations of all the metals were higher than their XRF concentrations except in Al and Ag metals. Cr had the highest distribution pattern while Ag metal had the lowest respectively. The target hazard quotient (THQ) for all metals were below minor hazard level. On the contrary, only Fe and Zn were below the Oral reference dose (RfD) value and the daily metal intake (DMI) respectively. The WilcoxonMann-Whitney test showed no significant difference between the concentration of the metals in XRF and AAS analysis results but identified the unusual behavior of Ag and Al metals; hence it depicted that both AAS and XRF analysis results were not sensitive to detect the different metal concentrations in the cards. Hence, similar coating specifications are utilized. The Kruskal Wallis test and Spearman correlation coefficient showed that the results from AAS and XRF were significantly different. Hence it showed that instrumentation showed sensitivity of metal concentrations from the recharge cards. This correlated with THQ, DMI, health risk index (HRI) risk assessment parameters that different coating specifications were used causing different values at same sampling points. Therefore, the results established that non-parametric tests are good analytical tools.
  • ItemOpen Access
    An experimental investigation of pristine barite adsorption on sodium oleate and sodium palmitate
    (Science Publishing Group, 2018) Nwoko, Christopher Ikpe Amadi; Nkwoada, Amarachi Udoka; Okoji, Josephine,; Opah, Solomon
    Characterization of the pristine barite mineral was established using a scanning electron microscope (SEM) and Fourier Transform Infra-Red (FTIR). Barite was applied for sodium oleate and sodium palmitate adsorption in aqueous solutions. Equilibrium adsorption data were fitted into two adsorption isotherms, three kinetic models and thermodynamic study. The concentration of the ion and pH in the solution proved to be a controlling factor in the adsorption process. Sodium oleate and sodium palmitate soaps adsorbed strongly onto the barite mineral at pH 9 and a temperature of 293k. They result was affected by the high bulk density and chemical resistance nature of barite indicated by successive increase in dosage amount. The effect of concentration and time typically gave a C-type adsorption isotherm. Adsorptive isotherm showed that sodium palmitate adsorption over natural barite was better described by the Langmuir adsorption isotherm while oleate desorption gave a good fitting with Freundlich isotherm. The adsorptive kinetics of sodium palmitate fitted well into pseudo 1st order and 2nd order kinetics. Intra particle diffusion was not the rate-determining step. Thermodynamic study showed a physiosorption that was exothermic. Hence the findings showed that pristine barite absorbs at optimum pH and temperature of 9 and 293k.
  • ItemOpen Access
    Characterization of selected honey in SouthEast Nigeria: Theoretical translation
    (U. P., 2017) Nwoko, C. I. A.; Nkwoada, A. U.; Ubeh, E. O.; Njoku, A.
    With the vast honey bee species producing honey for international export and consumption in Nigeria, there is need for theoretical translation of quality assessment and characterization of honey for human consumption. The physicochemical and mineral contents of some selected honey in the five South east geopolitical states of Nigeria was performed for above mentioned application. The results were evaluated with 3D plot to identify the statistical significance of the parameters analyzed. The levels of glucose and fructose were accepted by codex alimentation standard and rejected samples B, C, and G. A correlation of similar botanical origin was demonstrated in sample B, C and G and similarly observed in their moisture content been > 21%. The pH and electrical conductivity showed no significant variation. The codex hydroxyl methyl furfural standard identified samples B, E and L to be “aged honey” or falsified honey in circulation. The 3D plot showed the significant variation of hydroxyl methyl furfural content of samples. A hypothesis was observed when the samples and previously analyzed Nigerian samples were compared; metal concentration levels of Group 1 elements > Group 2 > transition metals in Nigerian honey and formed an identification trend.
  • ItemOpen Access
    Radiation levels around some X-ray diagnostic centres in Owerri, Imo State, Nigeria
    (U. P., 2018-07) Amakom, M. Chijioke; Orji, E. Chikwendu; Nkwoada, U. Amarachi; Nnonah, C. Daniel; Umunnakwe, C. Miriam
    Radiation levels were measured around eight diagnostic centres in Owerri, Imo State Nigeria using a portable Geiger Muller counter model GCA-04. The measurements were taken when the radiation sources (x-ray machines) were operational and non-operational. When the machines were non-operational, the background radiation ranged from 0.63 to 1.48 mSv/yr. When the machines were operational, the radiation levels ranged from 0.82 to 24.28 mSv/yr; this adds between 0.19 to 23.14 mSv/yr to the existing background radiation. The diagnostic centres used in this work have background radiation level below the world average dose limit of 2.16 mSv/yr for natural background radiation. Seven centres had annual dose rates that were below the 1.25mSv/yr dose limit for the public when the radiation source is not on and only one centre had a value still below the dose limit for the public when the radiation source was on. The other centres had higher values of annual dose rate when the safety of the general public is considered both for the cases when the radiation source was operational and non-operational.
  • ItemOpen Access
    The proximate analysis and biochemical composition of the waste peels of three cassava cultivars
    (U. P., 2016-11) Nwoko, Christopher I.; Enyinnaya, Onyekwe C; Okolie, Justus I.; Nkwoada, A.
    The nutrients yields from three different cassava waste peels were investigated. The values varied slightly with the different cassava cultivars. Sample A (NR 07/0220) had the highest moisture value (72.36%) while sample B (TMS/419) had the lowest moisture value (66.08%). The percentage ash content of sample C (TMS/3055) was comparably higher than the other cultivars indicating that the mineral contents of sample C (TMS/3055) was higher than that of other cultivars. Sample A (NR 07/0220) had the highest protein value (6.86%) while sample B (TMS/419) had the lowest protein value (5.73%). All the three cultivars have appreciable high value of carbohydrates with the highest value found in sample B (TMS/419) at 89.25%. The waste peels of the three cassava cultivars examined have appreciable levels of nutrients and can make useful contributions in animal nutrition and bioethanol. The codes are descriptor characteristic code adapted from the international plant such as the manihot esculenta specie (TMS) while the NR describes the newly released pro-vitamin, a variety with yellow roots.
  • ItemOpen Access
    Ammonia variations in Owerri metropolis and ecological impact
    (Conscientia Beam, 2020-04-15) Nnadozie, C. F.; Nkwoada, A. U.; Akagha, C. I.
    Ammonia emissions inventory is rarely reported in Nigeria and when at high levels is toxic to animals including humans. It is instructive to evaluate the levels of ammonia in metropolitan area as a priority to promote a clearer understanding of its distribution and interaction. The study investigated the levels of ammonia in different parts of Owerri Metropolis and its ecological impact. Ambient atmospheric NH3 concentrations have been measured for Owerri metropolis, away from point sources, for a period of three consecutive months in 2018 calendar year. Measured lowest mean NH3 concentrations have been in August at 0.04633 mg/L, which exceeded the critical loads and occupation exposure limits. There has been no significant change in the spatial variation in NH3 concentrations between the months albeit different locations varied significantly. The ecosystems where lichens and bryophytes are key species within the studied area may be under threat from loss of biodiversity while levels of human exposure to NH3 are completely unacceptable and require reducing and controlling measures. Hence, excess ammonia will induce elevated nitrification and denitrification driving higher greenhouse gas emissions
  • ItemOpen Access
    Phytochemical and GC/MS analysis of the rhizome of zingiber officinale plant grown in eastern part of Nigeria
    (U. P., 2018) Iwu Irenus Chinonye; Oze, Rita N; Onu, Uchenna Lynda; Nkwoada, Amarachi; Ukaoma, Adanma A
    Phytochemical and GC-MS analysis of zingiber offinale was carried out in the laboratory and with the aid of SHIMAZU Japan Gas Chromatography 5890-11 with a fused GC column OV 101 coated with polymethyl silicon (0.25 mm x 50 m). The result obtained confirmed the presence of alkaloids, flavonoids, saponins, glycosides, tannins and phenols in the plant. Twelve peaks were obtained from the he spectra of the GC-MS. peak 1 corresponds to Furan-3-carboxaldehyde with m/z 128 and molecular formulae C6H8O2, peak 2 was identified as Benzene -1-(1,5-dimethyl-4-4hexenyl)-4-methyl m/z 202 with molecular formulae C15H22. Peak 3 as ,1-,3-cyclohexadiene-5- (,5 diethyl-4-hexenyl -2-methyl (zingiberene) m/z 204 with molecular formulae C15H24, peak 4 as Alpha farnesene m/z 204 with molecular formulae C15H24. Peaks 5,6,7,8,9,10,1,12 occurred at m/z; 220,204, 194,242,,256,296,282, 296 corresponding to butylated hydrotoulene, C15H24,,cyclohexene-3- (1,5-dimethyl-4-hexenyl-6- methelene C15H24, 2-butanone-4-(4-hydroxy-3-methoxyphenyl C11H14O3, methyl tetra decanoate C15H32O2, n-hexadecanoic acid C16H32O2, 9-octadecenoic acid methyl ester C09H26O2, Octadec-9-enoic acid, C18H34O2, Gingerol C17H28O4 and Ricinoeic acid C18H24O2 respectively
  • ItemOpen Access
    Chemo-remediation of crude oil polluted soils obtained from recent polluted site in oil producing environs in Rivers State Nigeria
    (eSciPub, 2019) Iwu, Irenus Chinonye; Onu, Uchenna Lynda; Nkwoada, Amarachi; Onwumere, Fidelis
    The chemo- remediation of crude oil polluted soils from recent pollution sites in oil producing environs in River state was carried out by both in vivo and in vitro methods using macro-soil nutrients ( Nitrate, Phosphate and Potassium) as index for remediation. The soil samples were labeled A, B, C, D1 to D6, sample A was obtained from pollution free site used as a control.Sample C was crude oil polluted soil not treated with surfactant, sample B was crude oil polluted soil leached with surfactant and not mineralized. Samples D1-D6 were polluted soil samples, leached with surfactant and mineralized with fertilizer. The samples were leached with linear alkyl benzene sulphonate (LABS) and later mineralized with Nitrate, Phosphate and Potassium (N.P.K) fertilizer and returned to the site of excavation to fallow for four months. The samples were later re-excavated and taken to the laboratory for analysis. Nitrate and phosphate contents were obtained with the aid of spectrum lab 725 UV visible spectrophotometer and potassium content was determined by use of a flame photometer. Results showed that sample A had nitrate concentration of 330ppm, sample B had concentration of 21ppm, sample C had a concentration of 54ppm while samples D-D6 had concentrations ranging from300ppm to 420ppm.Similarly, The phosphate concentrations were 68.50ppm, 17.00ppn, 28.00ppm and 48.80-136.40ppm for sample A, B, C.D1-D6 respectively. The potassium concentrations were not different as concentrations of 46ppm, 12ppm, 28ppm and 38ppm-64ppm was recorded for samples A, B, C, and D1-D6 respectively. These results revealed that crude oils not only renders soils unusable but also destroys the nutrient availability in soils. The soils can therefore quickly be reclaimed by leaching them with surfactants and mineralizing them with adequate inorganic fertilizer.
  • ItemOpen Access
    Optimization of biodiesel development from non-edible indegenous feedstocks in Nigeria
    (Conscientia Beam, 2019-08-07) Nwoko, Christopher Ikpe Amadi; Nkwoada, Amarachi Udoka; Ogu, Helen Ugochi
    This study investigated the transesterification of Rubber seeds (Hevea brasiliensis), Avocado Pear seeds (Gratissima persea), and Nipa Palm Kennel seeds (Nypa frutican) locally sourced from Nigeria as an adsorbate for the esterification reaction of oleic acid with methanol. Reaction was catalysed by potassium hydroxide (KOH) to form methoxide oleate (biodiesel) adsorption from aqueous solution in batch model for the production of biodiesel. The results obtained showed that rubber seeds oil (RSO), Avocado pear seeds oil (APO) and Nipa palm kernel seed oil (NPKO) oil gave maximum biodiesel yields at 0.9 % w/v, 0.1 % w/v and 0.1 % w/v catalyst concentration respectively. Their biodiesel yields were 88.0 %, 92.0 % and 96.7% respectively. They recovered biodiesel were characterized as an alternative fuel via specific gravity, viscosity, acid value, flash point and cloud point. The results obtained showed that the specific gravity for RSO (0.886 kg/m3), APO (0.876 kg/m3) and NPKO (0.850 kg/m3)were fairly significant at temperature of 25 oC to other conventional petroleum diesel ASTM D 975, standard biodiesel ASTM D975, and standard biodiesel ASTM 6751 and EN14214.
  • ItemOpen Access
    Proficiency of graphene oxide in adsorption of Zn(II) ions from aqueous solution
    (Iranian Chemical Society, 2019-06) Udoka, N. A.; Kenechukwu, E. C.
    The efficient adsorption of metals on graphene oxide is often affected by the preparation method. Graphene oxide was prepared using a typical modified Hummers method for adsorptive removal of Zn2+ from aqueous solution. The experimental data were fitted into the Langmuir isotherm. The reaction was irreversible, but had a small energy of adsorption which was indicated by Freundlich isotherm model. Tempkin model and Dubinin Radushkevich revealed a physical adsorption process driven by a slow adsorptive process. The Pseudo 2nd order had the best correlation coefficient at 0.9958 while Langmuir was 0.9545. Elovich function indicated a non-spontaneous reaction, while the intra-particle diffusion was not the rate-determining step. The slow adsorption rate in pseudo 1st order correlated with the small adsorption energy shown by the Freundlich isotherm, and also correlated with the small boundary layer thickness shown by intra-particle diffusion. All adsorptive functions showed that some other competing mechanisms should exist. XRD showed an increased number of graphene layers, d-spacing and improved crystallite size. FTIR data showed the oxygen-containing groups on the graphene oxide surface. The study showed that the prepared graphene oxide could efficiently adsorb Zn2+, and that the adsorption is affected by the method of synthesis.
  • ItemOpen Access
    Physicochemical analysis and mineralogical composition of Enugu coal In Nigeria for potential utilization
    (U. P., 2017) Nwoko, Christopher Ikpeamadi; Nkwoada, Amarachi Udoka; Onu, Uchenna Lynda
    The abundance of coal in certain regions of Nigeria had been described as an alternative energy solution. The potential information obtained from the physicochemical and mineralogical characterization of coal samples in such regions has enabled scientist and government to make well informed decisions. Coal samples were obtained from Okpara Mine in Enugu state Nigeria and subjected to proximate, ultimate and mineralogical analyses. The results showed that the coal had uneven particle distribution with higher content of fixed carbon and lower amount of hydrogen and volatile matter. The mineral analyses showed that the coal was rich in silicon and aluminum. The rank was bituminous coal that can be utilized for power generation, steel industry, glass manufacturing and thermite process
  • ItemOpen Access
    Phytoextraction and risk assessment synergy of three edible plants in mining area
    (U. P., 2018-08-11) Nwoko, C. I. A.; Nkwoada, A. U.; Onu, L. U.; Njoku, P. C.; Ogbonnaya, D. O.
    The phytoextraction and risk assessment synergy of Arachis hypogea (groundnut), Zea maize (Corn) and Citrullus colocynthis L. (Melon) was investigated at a mining area contaminated with Cd, Cu, Pb and Zn heavy metals. The metal concentrations in plant matter and soil were determined using AAS. The average pH at 5.2 showed a slightly acidic soil while the total organic content and electrical conductivity were low. The studied metals exceeded the Nigerian FEPA guidelines as well as EU threshold values at the sites. Increase in Cd concentration in the North and South caused a corresponding decrease in plant yield. The maize appreciably accumulated more Pb than melon and groundnut. The phytoplants at the West sampling point accumulated more Zinc and melon grown at the west accumulated highest zinc concentrations of up to 1100 mg/kg. The Presence of Cu metal at low concentrations favoured an equivalent increase in weight of harvested groundnut seed. The Coefficient of Variation (CV) showed a correlation that hyperaccumulators had equivalent higher CV distribution. The values of Cd, Cu and Pb exceeded the Health Risk Index value of 1 in all the three edible phytoplants. The Cd demonstrated the lowest Bioconcentration Factor of (0.03) within the sampling area, among studied metals and the three edible plants. Thus Target Hazard Quotient (THQ) results agreed with the Daily Intake of Metals (DIM) results, that consumption of any of the three edible plants are unsafe and poses a health risk to locals; hence, the synergy of THQ and DIM in evaluating experimental data is detected in this study.