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optimization of the Physical Aperture of the Parabolic Reflector Antenna

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open Journal of Applied Sciences 2024年第1期14卷 182-192页

作者： Nkordeh Nsikan akindele Ayoola ololade oladoyin Amadi Eberi Ibinabo Bobmanuel Department of Business Analytic and Information Management University of Delaware Newark USA Department of Cybersecurity University of Dallas Dallas USA

In fields like astronomy and radar technology, high-gain antennas are required for long-distance communication. Due to its relatively large gain, the use of parabolic antennas has become very popular over time, because they can easily achieve gains of above 30 dB at microwave and higher frequencies. Today, most systems’ success depends on how well the antennas perform. These antennas are available in different types and sizes. Each antenna’s effective area usually has less than the actual physical area of the antenna surface. This means that the unused area of the antenna is massive, and a waste. The aim of the research is to show that the actual physical aperture of a parabolic antenna can be reduced as much as possible to equal the effective area, as given by the antenna formula, thereby saving manufacturing costs, improve the aesthetics. In other words, the focus of this work is to experimentally show that reflector antenna can be made of smaller sizes but better performance. Measurements were taken from different positions from a parabolic antenna, the signal level measured and compared with signal levels for optimal performance.

关键词： Parabolic Antenna Reception Manufacturing Cost

Production of Biogas from Co-Digestion of Cow Dung, Saw Dust and Maize Husk

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Advances in Chemical Engineering and Science 2018年第3期8卷 113-123页

作者： akindele oyetunde okewale Felix omoruwou Christiana Edward Anih Chemical Engineering Department College of Technology Federal University of Petroleum Resources Effurun Nigeria

The co-digestion of cow dung, with maize husk for biogas production at laboratory scale was investigated. The study was carried out at a temperature range of??24°C - 30°C and pH range of 5.5 - 6.5 for a period of 60 days with a total solid concentration of 7.4% in the digester sample (fermentation slurry). Water displacement method was used to collect the biogas produced which was subsequently measured. 444.8 mL was the cumulative biogas yield at the end of 60 days retention time in the digester 1, which comprised of cow dung, maize husk, and water. Digester 2, which is made up of sawdust, cow dung, and water produced negligible biogas at the end of 60 days of the experiment. X-RF analysis revealed high presence of elements like silica, aluminium oxides, and aluminium oxides in cow dung, maize husk, and sawdust respectively. The preponderance of alkanes and methyl group inmaize husk makes it to produce biogas compared to saw dust as shown by the Fourier transform infrared spectroscopy (FTIR) that was carried out to identify the various functional groups. The potential of maize husk to produced biogas was also established. The kinetic modeling shows that there was an increase in biogas yield as the retention time increases as depicted by the linear model.

关键词： Sawdust Biogas Cow Dung Maize Husk X-Ray Fluorescence FTIR

Assessment of two persistent bioaccumulative toxicants in the UNESCo protected river of osun-osogbo, Nigeria

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Ecological Processes 2017年第1期6卷 323-330页

作者： Emmanuel o.akindele Godwin o.olutona oyeshina G.oyeku Akinkunle V.Adeniyi Department of Zoology Obafemi Awolowo UniversityIle-IfeNigeria Department of Chemistry and Industrial Chemistry Bowen UniversityIwoNigeria Department of Biological Sciences Bowen UniversityIwoNigeria Institute of Ecology and Environmental Studies Obafemi Awolowo UniversityIle-IfeNigeria

Introduction:osun River dissecting the osun-osogbo Sacred Grove,though inscribed on the World Heritage List,has been rarely assessed for biodiversity values or *** this study,we investigated the concentrations of Cu and Zn in the benthic sediments and two dominant gastropod species(Melanoides tuberculata and Lanistes varicus)of the osun *** sediment and gastropod samples were collected on quarterly basis from June 2015 to March 2016 along the longitudinal stretch of the *** samples were digested and analysed for Cu and Zn using the atomic absorption ***:With the exception of September sampling period,the two metals recorded higher values in the animals than in the ***(1.23±0.81μg/g)was much lower(power(poth *** metals recorded much lower values than their average concentrations in the Earth’s crust as well as the recommended limits for freshwater ***,*** recorded higher bioaccumulation factor than ***:Findings from this study suggest that both metals posed no toxicological risk to the freshwater system of osun *** of both metals in the sediments as well as their accumulation factors in both gastropod species were indicative of an unimpacted freshwater system.

关键词： :Accumulation Benthic sediments Contamination Ecotoxicology Heavy metals Freshwater gastropods

Shear Band Formation in AISI 4340 Steel Under Dynamic Impact Loads:Modeling and Experiment

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 378-384页

作者： Daniel odoh Gbadebo owolabi akindele odeshi Horace Whitworth Department of Mechanical Engineering Howard University Department of Mechanical Engineering University of Saskatchewan57 Campus DriveSaskatoonSKS7N 5A9Canada

In this study, the occurrence of the adiabatic shear bands in AISI 4340 steel under high velocity impact loading was investigated using finite element analysis and experimental tests. The cylindrical specimen subjected to the impact load was divided into different regions separated by nodes using finite element method in ABAQUS environment with boundary conditions specified. The material properties were assumed to be lower in the region where the probability of strain localization is high based on prior experimental results in order to initialize the formation of the adiabatic shear bands. The finite element model was used to determine the maximum flow stress, the strain hardening, the thermal softening, and the time to reach the critical strain for the formation of adiabatic shear bands. Experimental results show that deformed bands were formed at low strain rates and there was a minimum strain rate required for the formation of the transformed band in the alloy and the cracks were initiated and propagated along the transformed bands leading to fragmentation under the impact loading. The susceptibility of the adiabatic shear bands to cracking was markedly influenced by the strain-rates and the initial material microstructure. The simulation results obtained were compared with the experimental results obtained from the AISI 4340 steel under high strain-rate loading in compression using split impact Hopkinson bars. A good agreement between the experimental and simulation results was obtained.

关键词： Adiabatic shear bands Finite element model Strain hardening Thermal softening Johnson-Cook model AISI 4340 steel

Hepatoprotective and in vivo antioxidant activities of the hydroethanolic leaf extract of Mucuna pruriens (Fabaceae) in antitubercular drugs and alcohol models

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Chinese Journal of Natural Medicines 2014年第4期12卷 273-283页

作者： Mercy B.obogwu Abidemi J.akindele olufunmilayo o.Adeyemi Department of Pharmacology Faculty of Basic Medical Sciences College of Medicine University of Lagos

AIM: Hepatotoxicity is a significantly increasing health problem worldwide, and the extent of the problem has stimulated interest in the search for hepatotherapeutic agents from plants. This study investigated the hepatoprotective and in vivo antioxidant activities of the hydroethanolic extract of Mucuna pruriens leaves in antitubercular and alcohol-induced hepatotoxicity assays in rats. METHoD: In each of the models used, seven groups were allotted. The different groups received normal saline(10 mL·kg-1, p.o.); hepatotoxicant(isoniazid-rifampicin, INH-RIF, 100 mg·kg-1, i.p. or 20% ethanol 5 g·kg-1, p.o.) and normal saline(10 mL·kg-1, p.o.); hepatotoxicant and extract at doses of 100, 200, and 400 mg·kg-1 p.o.; hepatotoxicant and silymarin 50 mg·kg-1 p.o.; and extract at 400 mg·kg-1 p.o.. on the 21st day of treatment, blood was collected for assessment of serum biochemical parameters and harvested liver samples were assessed for antioxidants. RESULTS: The hepatotoxicants significantly(P of alanine transaminase(ALT), aspartate transaminase(AST), alkaline phosphatase(ALP), bilirubin, and malondialdehyde(MDA); and reduced the levels of catalase(CAT), superoxide dismutase(SoD), glutathione peroxidase(GPx), and reduced glutathione GSH compared to control. M. pruriens significantly reversed(P on in the level of ALT, AST, ALP, and bilirubin caused by the hepatotoxicants. The extract(200 and 400 mg·kg-1) significantly reversed(P on in the level of in vivo antioxidants and increased the level of MDA produced by INH-RIF. M. pruriens(100-400 mg·kg-1) elicited significant reduction(P of MDA compared to the alcohol group. Silymarin also reversed the deleterious effects of the hepatotoxicants. CoNCLUSIoN: The hydroethanolic extract of Mucuna pruriens leaves possesses hepatoprotective activity with enhancement of in vivo antioxidants as a possible mechanism of action.

关键词： Mucuna pruriens Fabaceae Hepatoprotective Antioxidant Alcohol Antitubercular drugs

Effects of regenerative mechanical vibration on the mechanical integrity of ceramic diesel particulate filters

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Journal of Advanced Ceramics 2018年第1期7卷 5-16页

作者： Gbadebo oWoLABI akindele oDESHI Paul RAGALLER AlexANDer SAPPoK Department of Mechanical Engineering Howard University Department of Mechanical Engineering University of Saskatchewan CTS Corporation Boston Innovation office

In this study, the effects of mechanical vibration on the mechanical properties of ceramic diesel particulate filters(DPFs) were investigated. The goal is to determine how the mechanical vibration used in the regenerative ash cleaning process for these filters affects their mechanical integrity during subsequent reuse. Both virgin and vibrated DPF samples were subjected to compressive and 3-point flexural loading at three different loading rates along axial and tangential directions. Statistical analysis was conducted to determine the significance of variation in the compressive and flexural strengths of the DPFs as a result of exposure to mechanical vibration. The results show that there is no statistically significant difference in both compressive and flexural strengths of the virgin DPFs and the DPFs subjected to the same level of mechanical vibration typically used in ash cleaning of DPFs. When the intensity of vibration was doubled, the drop in compressive strength became statistically significant, but less than 10% under axial loading. However, no drop in flexural strength was observed for DPFs subjected to this high intensity of mechanical vibration. The safe threshold for mechanical vibration of ceramic filters is considered to be much higher than that currently used in vibration-based ash cleaning process.

关键词： diesel particulate filter(DPF) cordierite mechanical testing filter regeneration vibration based ash cleaning technology

Dynamic and ballistic impact behavior of biocomposite armors made of HDPE reinforced with chonta palm wood(Bactris gasipaes) microparticles

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Defence Technology（防务技术） 2018年第3期14卷 238-249页

作者： Edison E.Haro Jerzy A.Szpunar akindele G.odeshi Department of Mechanical Engineering University of Saskatchewan

The mechanical behavior of chonta palm wood(Bactris gasipaes) microparticles reinforced high density polyethylene(HDPE) under high strain-rate compressive and ballistic impact loading were *** palm wood microparticles were introduced into the HDPE via an extrusion process using parallel twin screw extruder to produce biocomposite containing 10, 20, 25, and 30 wt % chonta wood microparticles. In addition to mechanical tests, fractographic analysis was done to understand the failure mechanism in the biocomposites under dynamic and ballistic impact loads. The results indicate that both quasi-static and dynamic mechanical properties of HDPE are enhanced by reinforcement with chonta palm wood particles. The biocomposites containing 25 wt % wood microparticles exhibited the highest strength, stiffness, ballistic impact resistance and impact energy absorption capability. Introduction of microparticles of chonta palm wood as reinforcement into a polymeric matrix such as HDPE is therefore a promising method to develop biocomposites with enhanced capacity to withstand dynamic impact loading and absorb impact energy.

关键词： HDPE 弹道行为盔甲机械测试吸收能力密度聚乙烯挤出过程

Coag-Flocculation Kinetics of <i>Mucuna sloanei</i>Seed for Phosphorus Removal from Waste Water

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American Journal of Analytical Chemistry 2013年第12期4卷 732-738页

作者： Kamoru Akinpelu Babayemi okechukwu Dominic onukwuli Matthew Chukwudi Menkiti akindele oyetunde okewale Department of Chemical Engineering Anambra State University Uli Nigeria Department of Chemical Engineering Landmark University Omuaran Nigeria Department of Chemical Engineering Nnamdi Azikiwe University Awka Nigeria

Mucuna sloanei (MS) an environmentally friendly biomass was used as a coagulant for treatment of phosphorus containing waste water. The study evaluates the coag-flocculation efficiency of MS and its functional kinetic parameter response to varying pH and dosage of the waste water effluent. Coag-flocculation reaction order α, coag-flocculation rate constant K, and coagulation period τ1/2 were determined. The maximum coag-flocculation performance (97.4%) is recorded at rate constant, K of 1.24 × 10-4 l/mg·min, dosage of 400 mg/l, pH of 8 and coagulation period τ1/2 of 0.100 min while the minimum (61%) is recorded at K of 3 × 10-5 l/gm·min, dosage 100 mg/l, pH of 2 and τ1/2 of 8.900 mins. The results confirm that MS coagulant is an effective coagulant obeying the theory of fast coagulation in the conditions of the experiments.

关键词： Coag-Flocculation Mucuna slonaei Phosphorus

Curriculum Development for FAIR Data Stewardship

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Data Intelligence 2022年第4期4卷 991-1012,1033页

作者： Francisca oladipo Sakinat Folorunso Ezekiel ogundepo obinna osigwe Akinyinka Tosin akindele Directorate of Research InnovationsConsultancy and ExtensionKampala International University10102Uganda Virus over Data Network(VoDAN)-Africa and Asia Federal University Lokoja 260101Nigeria Department of Mathematical Sciences Olabisi Onabanjo UniversityP.M.B 2002Ago-IwoyeOgun State120005Nigeria Data Science Nigeria Lagos 105102Nigeria School of eLearning Projects Kampala International UniversityP.M.B 4000OgbomosoOyo stateNigeriaUganda

The FAIR Guidelines attempts to make digital data Findable, Accessible, Interoperable, and Reusable(FAIR). To prepare FAIR data, a new data science discipline known as data stewardship is emerging and, as the FAIR Guidelines gain more acceptance, an increase in the demand for data stewards is expected. Consequently, there is a need to develop curricula to foster professional skills in data stewardship through effective knowledge communication. There have been a number of initiatives aimed at bridging the gap in FAIR data management training through both formal and informal programmes. This article describes the experience of developing a digital initiative for FAIR data management training under the Digital Innovations and Skills Hub(DISH) project. The FAIR Data Management course offers 6 short on-demand certificate modules over 12 weeks. The modules are divided into two sets: FAIR data and data science. The core subjects cover elementary topics in data science, regulatory frameworks, FAIR data management, intermediate to advanced topics in FAIR Data Point installation, and FAIR data in the management of healthcare and semantic data. Each week, participants are required to devote 7–8 hours of self-study to the modules, based on the resources provided. once they have satisfied all requirements, students are certified as FAIR data scientists and qualified to serve as both FAIR data stewards and analysts. It is expected that in-depth and focused curricula development with diverse participants will build a core of FAIR data scientists for Data Competence Centres and encourage the rapid adoption of the FAIR Guidelines for research and development.

关键词： Data steward Data science FAIR Guidelines FAIR Digital technology FDP installation FAIR Data Trains Semantic web Personal Health Train