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Rare-earth and trace elements and hydrogen and oxygen isotopic compositions of Cretaceous kaolinitic sediments from the Lower Benue Trough, Nigeria: provenance and paleoclimatic significance

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Acta Geochimica 2019年第3期38卷 350-363页

作者： Anthony T.Bolarinwa sunday o.idakwo David L.Bish Department of Geology University of Ibadan Department of Earth Sciences Kogi State University Department of Geological Sciences Indiana University

This study evaluated the Cretaceous(Campanian–Maastrichtian) kaolinitic sediments of the Ajali/Mamu and Enugu/Nkporo Formations from the Lower Benue Trough of Nigeria. A combined method of inductively coupled plasma–mass spectrometry and isotope ratio mass spectrometry was used to investigate trace and rareearth element geochemistry and hydrogen and oxygen isotopic compositions. These data were then used to infer the sediments' provenance and paleoclimatic conditions during their deposition. The sediments contained low concentrations of most trace elements, with the exceptions of Zr(651–1352 ppm), Ba(56–157 ppm), V(38–90 ppm),and Sr(15.1–59.6 ppm). Average values of Co and Ni were1.5 and 0.7 ppm, respectively. Trace and rare earth element values were lower than corresponding values for upper continental crust and Post-Archean Australian Shale, with the exception of Zr. The samples showed only slight light rare-earth enrichment and nearly flat heavy rare-earth depletion patterns, with negative Eu and Tm anomalies,typical of felsic sources. Geochemical parameters such as La/Sc, Th/Sc, and Th/Co ratios support that the kaolinitic sediments were derived from a felsic rock source, likely deposited in an oxic environment.^(18 )o values ranged from+ 15.4 to + 21.2% for the investigated samples, consistent with a residual material derived from chemicalweathering of felsic rock and redeposited in a sedimentary basin(typical values of + 19 to + 21.2%). While in the basin, the sediments experienced extended interactions with meteoric water enriched in d D and d16 o. However,the variation in d D and d16 o values for the investigated samples is attributed to the high temperature of formation(54–91 °C). The d D and d^(18 )o values suggest that the sediments, although obtained from different localities within the Lower Benue Trough, formed under similar hot,tropical climatic conditions.

关键词： Rare-earth and trace elements oxygen/ hydrogen isotopic composition Kaolinitic sediments Lower Benue Trough Nigeria

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Source, Contamination Assessment and Risk Evaluation of Heavy Metals in the Stream Sediments of Rivers around olode Area SW, Nigeria

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Journal of Environmental & Earth Sciences 2023年第1期5卷 65-84页

作者： Stellamaris Isioma okonkwo sunday ojochogwu idakwo Mofolorunsho Samuel Kolawole olufemi Faloye Anthony Azubuike Elueze Department of Geology Federal University of TechnologyOwerriOwerriImo State460114Nigeria Department of Geology and Mining Ibrahim Badamasi Babangida UniversityLapaiNiger State740005Nigeria Department of Geology Federal UniversityOye-EkitiEkiti State360001Nigeria Department of Geology University of IbadanIbadan200005Nigeria

In order to investigate the source,contamination,and risk of heavy metals such as Pb,Zn,Cu,Ni,Co,Fe,Mn,and Cr,twelve(12)stream sediments and ten(10)rock samples were collected from pegmatite mining sites at olode and its environs inside Ibadan,Southwestern *** average values and order of abundance obtained followed the pattern:Mn(595.09)>Ba(80)>Cr(50.82)>V(45.09)>Zn(29.73)>Cu(13.82)>Co(13.82)>Sr(10.46)>Ni(9.73)>Pb(9.09)>Fe(1.59).These were greater than the background values,indicating that mining has a negative impact on the study area,as indicated by the high coefficient of variation and correlation values(>0.6)for Copper-Lead(0.929),Copper-Vanadium(0.970),Copper-Chromium(0.815),Lead-Vanadium(0.884),and *** the basis of the enrichment factor(EF),the olode sediments show extremely high enrichment for Mn and Ba in the research *** and Ni are most likely to blame for the elevated contamination levels,according to CF *** degree of contamination(CD),pollution load index(PLI),pollution index(PI),and modified pollution index(MPI)all revealed high levels of contamination in all stream sediment samples,whereas Igeo shows that the olode stream sediments are“practically uncontaminated to extremely contaminated by Ni,Co,and Mn”.Ni and Cu are the major regulating factors that are most likely causing the possible *** a result,these findings give important information for conducting appropriate ecological management research.

关键词： olode Heavy metals Stream sediments Risk assessment Contamination indices

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Prediction of selected biodiesel fuel properties using artificial neural network

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Frontiers in Energy 2015年第4期9卷 433-445页

作者： Solomon o. GIWA sunday o. ADEKoMAYA Kayode o. ADAMA Moruf o. MUKAILA Department of Agricultural and Mechanical Engineering College of Engineering and Environmental Studies Olabisi Onabanjo University lbogun Campus Ifo Ogun State Nigeria

Biodiesel is an alternative fuel to replace fossil- based diesel fuel. It has fuel properties similar to diesel which are generally determined experimentally. The experimental determination of various properties of biodiesel is costly, time consuming and a tedious process. To solve these problems, artificial neural network （ANN） has been considered as a vital tool for estimating the fuel properties of biodiesel, especially from its fatty acid （FA） composition. In this study, four ANNs have been designed and trained to predict the cetane number （CN）, flash point （FP）, kinematic viscosity （KV） and density of biodiesel using ANN with logsig and purelin transfer functions in the hidden layer of all the networks. The five most prevalent FAs from 55 feedstocks found in the literature utilized as the input parameters for the model are palmitic, stearic, oleic, linoleic and linolenie acids except for density network with a sixth parameter （temperature）. other FAs that are present in the biodiesels have been considered based on the number of carbon atom chains and the level of saturation. From this study, the prediction accuracy and the average absolute deviation of the networks are CN （96.69%; 1.637%）, KV （95.80%; 1.638%）, FP （99.07%; 0.997%） and density （99.40%; 0.101%）. These values are reasonably better compared to previous studies on empirical correlations and ANN predictions of these fuel properties found in literature. Hence, the present study demonstrates the ability of ANN model to predict fuel properties of biodiesel with high accuracy.

关键词： biodiesel fuel properties artificial neuralnetwork fatty acid prediction

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Degradation and mineralization of 2-chloro-, 3-chloro- and 4-chlorobiphenyl by a newly characterized natural bacterial strain isolated from an electrical transformer fluid-contaminated soil

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Journal of Environmental Sciences 2008年第10期20卷 1250-1257页

作者： Matthew o.Ilori Gary K.Robinson sunday A.Adebusoye Department of Botany and Microbiology University of Lagos Akoka Yaba Lagos Nigeria Department of Biosciences University of Kent Canterbury Kent CT2 7NJ United Kingdom

A bacterium classified as Achromobacter xylosoxidans strain IR08 by phenotypic typing coupled with 16S rRNA gene analysis was isolated from a soil contaminated with electrical transformer ?uid for over sixty years using Aroclor 1221 as an enrichment substrate. The substrate utilization profiles revealed that IR08 could grow on all three monochlorobiphenyls (CBs), 2,4’- and 4,4’-dichlorobiphenyl as well as 2-chlorobenzoate (2-CBA), 3-CBA, 4-CBA, and 2,3-dichlorobenzoate. Unusually, growth was poorly sustaine...

关键词： aerobic degradation chlorobenzoates mineralization monochlorobiphenyls natural strain polychlorinated biphenyls

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Synthesis of zinc-carboxylate metal-organic frameworks for the removal of emerging drug contaminant(amodiaquine)from aqueous solution

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Journal of Environmental Sciences 2018年第2期30卷 264-275页

作者： Adedibu C.Tella Samson o.owalude sunday J.olatunji Vincent o.Adimula sunday E.Elaigwu Lukman o.Alimi Peter A.Ajibade oluwatobi S.oluwafemi Department of Chemistry University of Ilorin Department of Chemistry and Polymer Science Stellenbosch University School of Chemistry and Physics University of Kwa Zulu-Natal Department of Applied Chemistry University of Johannesburg Doornfontein Campus Centre for Nanomaterials Science Research University of Johannesburg

We herein report the removal of amodiaquine, an emerging drug contaminant from aqueous solution using [Zn2（fum）2（bpy）] and [Zn4 o（bdc）3]（fum = fumaric acid; bpy =4,4-bipyridine; bdc = benzene-1,4-dicarboxylate） metal–organic frameworks（MoFs） as adsorbents. The adsorbents were characterized by elemental analysis, Fourier transform infrared（FT-IR） spectroscopy, and powder X-ray diffraction（PXRD）. Adsorption process for both adsorbents were found to follow the pseudo-first-order kinetics, and the adsorption equilibrium data fitted best into the Freundlich isotherm with the R2 values of 0.973 and0.993 obtained for [Zn2（fum）2（bpy）] and [Zn4 o（bdc）3] respectively. The maximum adsorption capacities foramodiaquine in this study were found to be 0.478 and 47.62 mg/g on the[Zn2（fum）2（bpy）] and [Zn4 o（bdc）3] MoFs respectively, and were obtained at p H of 4.3 for both adsorbents. FT-IR spectroscopy analysis of the MoFs after the adsorption process showed the presence of the drug. The results of the study showed that the prepared MoFs could be used for the removal of amodiaquine from wastewater.

关键词： Adsorption Metal–organic frameworks Amodiaquine Wastewater

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Effect of functional composite coating developed via sulphate and chloride process parameter on the UNS G10150 steel for structural and wear mitigation in defence application

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Defence Technology（防务技术） 2018年第3期14卷 196-203页

作者： ojo sunday Isaac Fayomi Department of Mechanical Engineering Covenant University Department of Chemical Metallurgical and Materials Engineering Tshwane University of Technology

The major engineering challenge of materials in defence technologies is the vulnerability of based metals to structural and wears deformation in service. In this paper, structural formation, mechanical and thermal stability behavior of developed composite coating of Zn-30 Al-7%Ti/Sn chloride bath and Zn-30 Al-7%Ti/Sn sulphate bath was investigated and compared to provide mitigation against failure. The thermal ageing property was done for 2 h at 600C via isothermal furnace. The structural, interfacial effect and stability behaviors of the co-deposited alloys were evaluated using scanning electron microscope equipped with energy dispersive spectrometer(SEM/EDS), atomic force microscope(AFM) and Xray diffractometer(XRD). The hardness and wear properties of the deposited coatings were examined with diamond base micro-hardness tester and reciprocating sliding tester respectively. The result shows that Zn-30 Al-7%Ti/Sn sulphate co-deposition contributed to increase hardness and wear resistance than Zn-30 Al-7%Ti/Sn chloride bath alloy. The stable crystal growth and significant performance of Zn-30 Al-7%Ti/Sn sulphate are link to the intermetallic phase hybrid of Zn Al, Zn4 Ti Al2, Zn3 Al Ti. Besides, it was observed that Zn-30 Al-7%Ti/Sn sulphate has excellent thermomechanical stability at harsh temperature,due to the deposition of Sn/Ti on steel; leading to formation of super-hard interface. However, it was established that co-deposition of mild steel with Zn-30 Al-7%Ti/Sn in sulphate bath significantly improved the structural and wear performance. It was shown that the hardness and wear of the developed composite Zn-30 Al-7%Ti/Sn is increased by about 80% compared to as received sample and about 25% compared with Zn-30 Al-7%Ti/Sn chloride coating developed. The improvement was proved to be an interference of zinc-composite growth. Thus, this work shows that sulphate induced Zn-30 Al-7%Ti/Sn via generation of controllable process parameter can provide significant improv

关键词：防卫技术硫酸盐氯化物低碳钢结构涂层合成 UNS

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Comparison of the thermal properties of clay samples as potential walling material for naturally cooled building design

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Journal of Environmental Sciences 2003年第1期15卷 65-68页

作者： sunday E.ETUK IDARA o.AKPABIo E.M.UDoH Department of Physics University of UYO UYO Akwa Ibom State 尼日利亚

The thermal properties of different clay samples obtained from locations in Akwa Ibom State, Nigeria were investigated and compared, and in order to establish their suitability as building material from energy conservation point of view. The results showed that stoneware clay has the highest solar radiation absorptivity of 22 32 m -1 while kaolin clay has the lowest radiation absoptivity of 14 46 m -1 A model for the prediction of temperature variation with thickness of the samples was developed. Results showed that kaolin would make the best choice for the design of a naturally cooled building.

关键词： thermal properties clay walling material naturally cooled building

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A compositional function hybridization of PSo and GWo for solving well placement optimisation problem

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Petroleum Research 2022年第3期7卷 401-408页

作者： Daniel ocran sunday sunday Ikiensikimama Eric Broni-Bediako University of Mines and Technology(UMaT) Department of Petroleum and Natural Gas EngineeringTarkwaGhana Universty of Port Harcourt Department of Petroleum and Natural Gas EngineeringPort HarcourtNigeria

Advances in technology and optimisation are helping to improve decision making in the oil and gas ***,most of the traditional metaheuristic algorithms applied in well placement optimisation problems suffer from extensive parameter experimentations and local optimum trapping *** couples with the complex and heterogeneous nature of hydrocarbon reservoirs and increased decision variables poses severe simulation process *** study considered a functional composition integration approach to formulate a robust hybrid metaheuristic algorithm called *** HGWo-PSo leverages on the strengths of Grey Wolf optimiser(GWo)and Particle Swarm optimisation(PSo)and the Clerc's parameter setting considerations.A rigorous approach which enforces regulatory agreed minimum well spacing was incorporated in the optimisation *** models ranging from unimodal to multimodal spatial systems were used as examples to test the explorative and exploitative capabilities of the *** this paper we show the performance curve and statistical analysis of HGWo-PSo as a well placement algorithm and compares its performance with that of standalone PSo,and GWo and the traditional Genetic Algorithm(GA).Results revealed that the HGWo-PSo demonstrated comparative performances in terms of exploration and exploitation obtaining the best optimal solutions which give highest contractor's NPVs in majority of cases ***,the means and standard deviations for HGWo-PSo among the various runs showed consistent and efficient *** Wilcoxon signed rank test conducted gave very low p-values suggesting uniqueness of HGWo-PSo from the other metaheuristic ***,the computational speed of HGWo-PSo was relatively better as compared to the individual GWo and PSo in most the test *** simulation results for all test cases confirm that implementation of HGWo-PSo can cause considerable improvement in locations of wells even in hete

关键词： Well location optimisation Metaheuristic algorithms oilfield development Hybridisation

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Differential degradation of crude oil (Bonny Light) by four Pseudomonas strains

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Journal of Environmental Sciences 2009年第2期21卷 243-248页

作者： oluwafemi S.obayori sunday A.Adebusoye Adams o.Adewale Ganiyu o.oyetibo odunola o.oluyemi Rashid A.Amokun Matthew o.Ilori Department of Microbiology Lagos State University Department of Botany and Microbiology University of Lagos

Four hydrocarbon degraders isolated from enriched oil- and asphalt-contaminated soils in Lagos, Nigeria, were tested for their petroleum degradation potentials. All the isolates were identified as species of Pseudomonas. Pseudomonas putida P 11 demonstrated a strong ability to degrade kerosene, gasoline, diesel, engine oil and crude oil while P. aeruginosa BB3 exhibited fair degradative ability on crude oil, gasoline, engine oil, anthracene and pyrene but weak on kerosene, diesel and dibenzothiophene. Pseudomonas putida WL2 and P. aeruginosa MVL1 grew on crude oil and all its cuts tested with the latter possessing similar polycyclic aromatic potentials as P11. All the strains grew logarithmically with 1-2 orders of magnitude and with generation time ranging significantly between 3.07 and 8.55 d at 0.05 level of confidence. Strains WL2 and MVL1 utilized the oil substrate best with more than 70% in 6 d experimental period, whereas the same feat was achieved by P11 in 12 d period. BB3 on the other hand degraded only 46% within 6 d. Interestingly, data obtained from gas chromatographic analysis of oil recovered from the culture fluids of MVL1 confirmed near-disappearance of major peaks （including aliphatics and aromatics） in the hydrocarbon mixture.

关键词： biodegradation crude oil hydrocarbons pollution Pseudomonas strains

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Long-term consumption of virgin coconut (Cocos nucifera) oil diet impairs learning and memory in CD1 mice

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Chinese Herbal Medicines 2020年第4期12卷 414-420页

作者： sunday A.Bisong Clement o.Nku olushola A.Sanya sunday o.Ita Victor A.Fischer Favour E.Abuo Department of Physiology College of Medical SciencesUniversity of CalabarCalabar 540242Nigeria Department of Physiology University of UyoUyo 520232Nigeria Department of Anatomy University of CalabarCalabar 540242Nigeria Department of Physiology Federal UniversityNdufu-Alike IkwoEbonyi State 482131Nigeria

objective:Virgin coconut oil(VCo)has been used in the management of dementia in Alzheimer’s disease(AD).Therefore,this research investigated the effect of long-term consumption of VCo diet on learning and memory in CD1 ***:Thirty male CD1 mice(divided into three groups,n=10)were fed with standard rodent chow(control),5%and 20%VCo diets(respectively)for 28 *** Morris Water Maze(MWM)test was used to test the effect of VCo on visuo-spatial learning and memory,while the Novel object Recognition Test(NoRT)was used to measure short-and long-term recognition ***:Learning performance of mice did not differ in the *** the probe trial,duration in the retention quadrant and annulus crossings were lower(Po diet groups compared to the control diet group,showing that VCo impaired visuo-spatial *** the NoRT,mice showed more total approaches in the 20%VCo diet group(Pompared to control and the 5%VCo diet groups during the short-term memory *** the long-term memory retention test,the total approaches were also higher in the 20%VCo group compared to control and 5%VCo group(P>0.05).The discrimination index was also lower in the 20%VCo group compared to control and 5%VCo diet groups indicating impaired long-term cognitive memory in mice given 20%VCo *** examination of brains showed damage within the CA1 pyramidal cell layer of the hippocampus in the 20%VCo diet group,in line with the behavioural ***:Long-term consumption of virgin coconut oil diet impairs memory in mice.

关键词： Cocos nucifera Linn learning and memory mice virgin coconut oil

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