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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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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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Numerical modeling and parametric sensitivity analysis of heat transfer and two-phase oil and water flow characteristics in horizontal and inclined flowlines using OpenFOAM

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Petroleum Science 2023年第2期20卷 1183-1199页

作者： Nsidibe sunday Abdelhakim Settar Khaled Chetehouna Nicolas Gascoin INSA Centre Val de Loire UniversitéOrléansPRISME EA 4229F-18020BourgesFrance

Estimating the oil-water temperatures in flowlines is challenging especially in deepwater and ultra-deepwater offshore applications where issues of flow assurance and dramatic heat transfer are likely to occur due to the temperature difference between the fluids and the surroundings. Heat transfer analysis is very important for the prediction and prevention of deposits in oil and water flowlines, which could impede the flow and give rise to huge financial losses. Therefore, a 3D mathematical model of oil-water Newtonian flow under non-isothermal conditions is established to explore the complex mechanisms of the two-phase oil-water transportation and heat transfer in different flowline inclinations. In this work, a non-isothermal two-phase flow model is first modified and then implemented in the InterFoam solver by introducing the energy equation using OpenFOAM® code. The Low Reynolds Number (LRN) k-ε turbulence model is utilized to resolve the turbulence phenomena within the oil and water mixtures. The flow patterns and the local heat transfer coefficients (HTC) for two-phase oil-water flow at different flowlines inclinations (0°, +4°, +7°) are validated by the experimental literature results and the relative errors are also compared. Global sensitivity analysis is then conducted to determine the effect of the different parameters on the performance of the produced two-phase hydrocarbon systems for effective subsea fluid transportation. Thereafter, HTC and flow patterns for oil-water flows at downward inclinations of 4°, and 7° can be predicted by the models. The velocity distribution, pressure gradient, liquid holdup, and temperature variation at the flowline cross-sections are simulated and analyzed in detail. Consequently, the numerical model can be generally applied to compute the global properties of the fluid and other operating parameters that are beneficial in the management of two-phase oil-water transportation.

关键词： Flow assurance Flow pattern Heat transfer Flowlines Two-phase flow Global sensitivity analysis

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Anti-Corrosion and Tribo-Mechanical Properties of Co-deposited Zn–SnO_2 Composite Coating

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 521-530页

作者： Ojo sunday Isaac Fayomi Abimbola Patricia Idowu Popoola Department of Chemical Metallurgical and Materials EngineeringTshwane University of Technology Department of Mechanical Engineering Covenant University

Zn-SnO2 composite coatings were prepared by direct potential using electrolytic co-deposition technique from sulfate solution. The effect of Zn2＋ and SnO2 concentrations in deposited bath on the mechanical properties and mor- phological characteristics of the composite coatings were examined. The characterizations of the sample were analyzed using scanning electron microscopy couple with energy dispersive spectroscopy （SEM/EDS）, X-ray diffraction （XRD） and atomic force microscopy （AFM）. The electrochemical degradation behavior of the samples in 3.65 wt.% NaCl solution was studied using potentiodynamic polarization technique and characterized by high-resolution optical microscope. From all the fabricated composite coatings, obvious diffraction peaks were observed with Zn-7Sn-S-0.3V film with Zn2Sn7, Sn, Zn2Sn5 and Zn phases, confirming the presence and formation of Zn-SnO2 coating. The XRD pattern shows that the presences of SnO2 particle remarkably play a major role in the precipitation and orientation of the alloy matrix. From the SEM/EDS and AFM results, the deposits show that composite particle and proper bath composition have strong influence on the microstructure. An enhanced corrosion resistance was attained as a result of the induced particles.

关键词： Metal matrix composite Co-deposition Mechanical property Corrosion resistance

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Inclusion engineering and metallurgy of calcium treatment

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Journal of Iron and Steel Research International 2018年第2期25卷 133-145页

作者： sunday Abraham Rick Bodnar Justin Raines Yufeng Wang SSAB Americas Muscatine IA 52761 USA

Although a great deal of research has been done in the area of inclusion control during steelmaking, a complete description of the process of inclusion modification and shape control cannot be found in literatures. As a result, the terms ＂inclusion modification＂ and ＂shape control＂ are often used loosely in the technical community. To utilize the full potential offered by a calcium treatment, it is important to understand why an inclusion whose composition has been modified may not necessarily have its shape modified. With the purpose of decoupling the process of inclusion phase change from inclusion shape control, and to provide a complete description of the metallurgy of calcium treatment, a detailed literature survey has been performed on the subject. By coupling the survey with a new concept developed to tailor the cleanliness of steels to the intended applications, the hope is to provide the reader with valuable information on calcium treatment for inclusion modification and shape control.

关键词： Nonmetallic inclusion Cleanliness Calcium treatment Inclusion modification Inclusion shape control

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Antibacterial and antioxidant activities of hydroalcoholic stem bark extract of Schotia latifolia Jacq

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Asian Pacific Journal of Tropical Medicine 2011年第12期4卷 952-958页

作者： sunday Oyewole Oyedemi Anthony Jide Afolayan School of Biological Sciences University of Fort HareAlice 5700South Africa

Objective:To investigate the antibacterial and antioxidant activities of hydroalcoholic extract of Scholia latifolia（***） bark commonly used in South Africa traditional medicine for the treatment of various ***:The antibacterial test and MIC was determined by using agar well diffusion and dilution methods respectively against eight strains of bacteria. The total phenol,proanthocyanidin and flavonoid contents of *** were assessed using Standard *** antioxidant activity of the extract was evaluated using ferric reducing power and the free radical scavenging activity against 1.1-diphenyl-2-picrylhydrazyl（DPPH）, 2.2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic-acid（ABTS）,nitric oxide（NO）,hydrogen peroxide（H2O2） and lipid oxidation（LO）.Results:The antibacterial activity demonstrated an appreciable effect against all the gram positive bacteria at MIC between 0.016 and 10 mg/ml. while that of gram negative bacteria was above 10 mg/*** plant extract exhibited high concentration of proanthocyanidin[（300.00±0.10） mg CE/g].followed by flavonoid[（12.46±0.04 mg） TE/g]and phenol[（1 l.06±0.03） mg QE/g]***,the extract at 0.5 mg/mL scavenges ***.H2O2.LO and NO by 87.55%.89.47%.77.15%.86.48%and 77.75%of the radicals *** reducing power was also found to be concentration dependent Conclusions: Our data suggest that *** extract has antibacterial and antioxidants activity and thus could be used as alternative therapv against antibiotic resistance bacteria and to prevent man) radical related diseases.

关键词： Scotia latifolia Polyphenols Antioxidant activity Free radicals Antibacterial

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Diagenetic and Reservoir Quality Variation of Miocene Sandstone Reservoir Analogues from Three Basins of Southern California,USA

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Journal of Earth Science 2020年第5期31卷 930-949页

作者： sunday E.Okunuwadje David MacDonald Stephen Bowden School of Geosciences University of AberdeenAberdeen AB243UEUK Department of Geology University of BeninBenin City PMB 1154Nigeria

The Miocene sandstone deposits in the Southern California region are important hydrocarbon reservoirs. However, their development has been very challenging due to the wide variability in their reservoir quality. These sandstones have been studied from three sedimentary basins by petrographic thin section, scanning electron microscope, and X-ray diffraction to evaluate and compare the influence of diagenesis on their reservoir quality in these basins. Four petrofacies, namely P1(sand injectite or dyke), P2(sub-marine fan), P3(turbidite and marine-influenced alluvial fans) and P4(continental sandstones) have been identified. P1 and P2 characterise the sandstones in the San Joaquin forearc basin and are affected by kaolinite and extensive early calcite diagenesis. P3 and P4 delineate the sandstones in the Cajon Valley and Salton Trough strike-slip basins and are dominated by smectite, mixed illite-smectite, early calcite and late calcite diagenesis. Early calcite cement in P3 and P4 is in lower proportion than in P1 and P2. Although the dissolution of these sandstones by acidic fluids did not have a pattern, it, however, has the most considerable influence on P2 creating moldic pores which are expected to increase pore connectivity. The relatively abundant dissolution pores in P2, together with the absence of late authigenic calcite and illite clay in comparison to the other petrofacies studied are likely to make this sandstone facies the best reservoir targets in the Southern California region. These rocks are analogous to producing reservoirs in the region. However, because, petroleum accumulation in these reservoirs are compartmentalized by early calcite cement, maximum recovery using acidified fluids is recommended to dissolve the calcite-filled pores in order to increase connectivity of their pore network and enhance flow potential.

关键词： diagenesis petrofacies reservoir quality Miocene California

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Novel Taguchi scheme-based DEMATEL methods and DEMATEL method for the principal performance indicators of maintenance in a food processing industry

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International Journal of Intelligent Computing and Cybernetics 2021年第3期14卷 363-397页

作者： Victor Chidiebere Maduekwe sunday Ayoola Oke Department of Mechanical Engineering Faculty of EngineeringUniversity of LagosAkoka YabaNigeria

Purpose-Key performance indicators(KPIs)of maintenance systems serve as benchmarks to workers and organizations to compare their goals for decision-making ***,the effects of one KPI on the other are least known,restraining decisions on prioritization of *** article examines and prioritizes the KPIs of the maintenance system in a food processing industry using the novel Taguchi(T)scheme-decisionmaking trial and evaluation laboratory(DEMATEL)method,Taguchi-Pareto(TP)scheme-DEMATEL method and the DEMATEL ***/methodology/approach-The causal association of maintenance process parameters(frequency of failure,downtime,MTTR,MTBF,availability and MTTF)was ***,the optimized maintenance parameters were infused into the DEMATEL method that translates the optimized values into cause and effect responses and keeping in view the result of *** collection was done from a food processing plant in ***-The results indicated that downtime and availability have the most causal effects on other criteria when DEMATEL and T-DEMATEL methods were respectively applied to the ***,the frequency of failure is mostly affected by other criteria in the key performance indication selection using the two *** combined Taguchi scheme and DEMATEL method is appropriate to optimize and establish the causal relationships of ***/value-Hardly any studies have reported the joint optimization and causal relationship of maintenance system ***,the current study achieves this goal using the T-DEMATEL,TP-DEMATEL and DEMATEL methods for the first *** applied methods effectively ease decisions on prioritization of KPIs for enhancement.

关键词： Maintenance Performance DEMATEL Food processing Indicators

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Optimized Hybrid Block Adams Method for Solving First Order Ordinary Differential Equations

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Computers, Materials & Continua 2022年第8期72卷 2947-2961页

作者： Hira Soomro Nooraini Zainuddin Hanita Daud Joshua sunday Department of Fundamental and Applied Sciences Universiti Teknologi PETRONAS32610Seri IskandarPerakMalaysia Department of Mathematics University of Jos930003JosNigeria

Multistep integration methods are being extensively used in the simulations of high dimensional systems due to their lower computational *** block methods were developed with the intent of obtaining numerical results on numerous points at a time and improving computational *** block methods for instance are specifically used in numerical integration of initial value *** this paper,an optimized hybrid block Adams block method is designed for the solutions of linear and nonlinear first-order initial value problems in ordinary differential equations(ODEs).In deriving themethod,the Lagrange interpolation polynomial was employed based on some data points to replace the differential equation function and it was integrated over a specified ***,the convergence properties along with the region of stability of the method were *** was concluded that the newly derived method is convergent,consistent,and *** method was also found to be A-stable implying that it covers the whole of the left/negative half *** the numerical computations of absolute errors carried out using the newly derived method,it was found that the method performed better than the ones with which we compared our results *** also showed its superiority over the existing methods in terms of stability and convergence.

关键词： Initial value problem(IVPs) linear multi-step method block interpolation hybrid Adams-Moulton method

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Pathways for Sustainable Utilization of Waste Chicken Eggshell

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Journal of Renewable Materials 2022年第8期10卷 2217-2246页

作者： Omojola Awogbemi Daramy Vandi Von Kallon Victor sunday Aigbodion Department of Mechanical and Industrial Engineering Technology University of JohannesburgJohannesburgSouth Africa African Centre of Excellence ACESPED University of NigeriaNsukkaNigeria Faculty of Engineering and the Built Environment University of JohannesburgJohannesburgSouth Africa

Chicken eggshell is one of the most common wastes generated from households,restaurants and other food processing *** Chicken Eggshells(WCES)also constitutes an environmental nuisance and ends up discarded at dumping site with no consideration of further *** main constituent of WCES is calcium carbonate from which calcium or calcium oxide can be extracted for various *** current effort reviews recently published literature on the diverse applications of *** considered utilization avenues include catalysts for biofuel production,construction industry,wastewater purification,industrial sector,food industry,medical,and agricultural *** specific areas of application apart from the transesterification reactions include cement additives and replacement in concrete,asphalt binder,adsorbent of metals and dyes,production of hydroxyapatite,food supplement and fortification,dentistry,therapeutics,bone formation,drug delivery,poultry feeds as well as organic *** most of the identified applications,the WCES is subjected to pretreatment and other modification techniques before *** conversion of WCES to valuable products is a cost-effective,safe,environmentally friendly,non-toxic and viable means of waste disposal and *** investigations are needed to further explore the benefits derivable from this bioresource.

关键词： Waste chicken eggshells catalysts food supplements medical applications waste utilization biofuel production

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