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Journal of Earth Science 2024年第1期35卷 16-28页

作者： Landry Soh Tamehe Huan Li Sylvestre Ganno Zuxing Chen Yanick Brice Lemdjou Safiyanu Muhammad Elatikpo School of Geosciences and Info-Physics Central South UniversityChangsha 410083China department of Earth Sciences University of Yaounde IYaounde 3412Cameroon Institute of Oceanology Chinese Academy of SciencesQingdao 266071China department of Geology Ahmadu Bello University ZariaZaria 810107Nigeria

The Bipindi iron ore district is located in the central section of the Nyong Complex at the northwestern margin of the Congo Craton in Southwest *** iron district contains numerous iron mineralization hosted by the Mewongo,Bibole,Kouambo,and Zambi banded iron formations(BIFs).These BIFs contain magnetite as the main iron ore mineral associated with pyrite,and gangue minerals are quartz with minor chlorite and *** origin of iron ore from these BIFs was investigated using a combination of in-situ magnetite and whole-rock *** studied BIF ore samples have a narrow range of TFe between 30.90 wt.%and 43.20 wt.%,indicating a low-grade *** geochemical signatures of magnetite such as low contents of base metals(e.g.,Cu,Co,V,and Zn)and low Co/Zn ratios600 and>75,respectively),we suggest that magnetite was derived from a mixture of seawater and~0.1%low-temperature hydrothermal fluids in an oxidizing ***,low-temperature hydrothermal and later metamorphic fluids were necessary for the transformation of the protolith Nyong Complex BIFs to iron ore.

关键词： banded iron formations iron ore geochemistry Congo Craton trace element composition LA-ICP-MS

Effects of Furniture Ergonomics on Student’s Satisfaction in a Library Facility

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Journal of Civil Engineering and Architecture 2024年第8期18卷 384-393页

作者： Dodo Mansir department of Building Faculty of Environmental DesignAhmadu Bello UniversityZaria 810107Nigeria

Building occupants are not immune to ill-health as a result of time they spend in a *** paper seeks to examine the effects furniture ergonomics have on student’s satisfaction in the library of Universiti Teknologi Malaysia.A pilot survey was initially conducted in the library through a one-to-one interaction with students to fetch their opinions on the general effects of the *** observation through several walkthroughs was also conducted by the researchers to compare and validate responses *** hundred and sixty-five students that come from fifteen nationalities are surveyed.A structured questionnaire is used to collect data on the respondents’opinions on the size,shape,arrangement and comfort of the *** cross tabulation,Spearman’s rho and Kendall’s Tau-b are used to establish *** show that amongst the effects studied,there are significant positive relationships between students’satisfaction of furniture ergonomics as against back-strain and lack of *** implies that the more the furniture arrangements,size and shape are perceived unsatisfactory,the more their effects on back-strain and lack of concentration towards the *** paper further recommends that library management should see to designing IEQ(Indoor Environmental Quality)guidelines that will mitigate the effects of furniture ergonomics thus improving student’s satisfaction.

关键词： Ergonomics furniture library satisfaction students

Predictive modelling of volumetric and Marshall properties of asphalt mixtures modified with waste tire-derived char:A statistical neural

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Journal of Road Engineering 2024年第3期4卷 318-333页

作者： Nura Shehu Aliyu Yaro Muslich Hartadi Sutanto Noor Zainab Habib Aliyu Usman Abiola Adebanjo Surajo Abubakar Wada Ahmad Hussaini Jagaba department of Civil and Environmental Engineering Universiti Teknologi PETRONASSeri Iskandar 32610Malaysia department of Civil Engineering Ahmadu Bello UniversityZaria 810107Nigeria Institute of Infrastructure and Environment Heriot-Watt UniversityDubai 294345United Arab Emirates School of Civil Engineering Central South UniversityChangsha 410075China Interdisciplinary Research Centre for Membranes and Water Security King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

The goals of this study are to assess the viability of waste tire-derived char(WTDC)as a sustainable,low-cost fine aggregate surrogate material for asphalt mixtures and to develop the statistically coupled neural network(SCNN)model for predicting volumetric and Marshall properties of asphalt mixtures modified with *** study is based on experimental data acquired from laboratory volumetric and Marshall properties testing on WTDCmodified asphalt mixtures(WTDC-MAM).The input variables comprised waste tire char content and asphalt binder *** output variables comprised mixture unit weight,total voids,voids filled with asphalt,Marshall stability,and *** coupled neural networks were utilized to predict the volumetric and Marshall properties of asphalt *** predictive modeling,the SCNN model is employed,incorporating a three-layer neural network and preprocessing techniques to enhance accuracy and *** optimal network architecture,using the collected dataset,was a 2:6:5 structure,and the neural network was trained with 60%of the data,whereas the other 20%was used for cross-validation and testing *** network employed a hyperbolic tangent(tanh)activation function and a feed-forward *** to the results,the network model could accurately predict the volumetric and Marshall *** predicted accuracy of SCNN was found to be as high value>98%and low prediction errors for both volumetric and Marshall *** study demonstrates WTDC's potential as a low-cost,sustainable aggregate *** SCNN-based predictive model proves its efficiency and versatility and promotes sustainable practices.

关键词： Waste tire Neural network Sustainable practices Asphalt mixtures Predictive model

Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 115-136页

作者： Yusuf Suleiman Dambatta Changhe Li Mohd Sayuti Ahmed A D Sarhan Min Yang Benkai Li Anxue Chu Mingzheng Liu Yanbin Zhang Zafar Said Zongming Zhou School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Mechanical Engineering department Ahmadu Bello UniversityZaria 810106Nigeria Mechanical Engineering department University of Malaya50603 Kuala LumpurMalaysia department of Mechanical Engineering King Fahd University of Petroleum&Minerals31261 DhahranSaudi Arabia State Key Laboratory of Ultra-Precision Machining Technology Department of Industrial and Systems Engineer-ingThe Hong Kong Polytechnic UniversityHong KongChina College of Engineering University of Sharjah27272 SharjahUnited Arab Emirates Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266100China

Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining *** involve the spray of an infinitesimal amount of mist-like lubricants during machining *** MQL system is affirmed to exhibit an excellent machining performance,and it is highly *** nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL *** have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these *** work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)*** effect different grinding modes and lubrication systems during the grinding operation was also *** concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower *** quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface *** was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication ***,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%***,regression analysis was used to obtain an optimum parameter *** observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics.

关键词： Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants Nanofluid Grinding Ceramic

Natural convection flow in a vertical annulus with time-periodic thermal boundary conditions

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Propulsion and Power Research 2019年第1期8卷 47-55页

作者： Basant K.Jha Michael O.Oni department of mathematics.ahmadu bello university Zaria.Nigeria

This paper presents an analytical solution for natural convection flow in a vertical annulus due to time-periodic heating of annulus ***-form expressions for velocity,temperature,skin-friction,mass flow rate and rate of heat transfer which is expressed as Nusselt number are obtained by solving the present mathematical model after separating into steady component and periodic *** effects of pertinent parameters such as Strouhal number(St),Prandtl number(Pr)and radius ratio(λ)are shown with the aid of contour and line *** indicate that the role of Strouhal number and Prandtl number is to decrease fluid velocity,temperature and ***,increase in Strouhal number increases the temperature phase-lag.

关键词： Natural convection Fully developed flow Time-periodic heating Vertical annulus Strouhal number

Time-dependent MHD Couette flow of rotating fluid with Hall and ion-slip currents

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Applied mathematics and Mechanics(English Edition) 2012年第4期33卷 399-410页

作者： B.K.JHA C.A.APERE department of mathematics Ahmadu Bello University

The unsteady magnehydrodynamics （MHD） Couette flow of an electrically conducting fluid in a rotating system is investigated by taking the Hall and ion-slip currents into consideration. The derived fundamental equations on the assumption of a small magnetic Reynolds number are solved analytically with the well-known Laplace transform technique. The unified closed-form expressions axe obtained for the velocity and the skin friction in the two different cases of the magnetic field being fixed to either the fluid or the moving plate. The effects of various parameters on the velocity and the skin friction axe discussed by graphs. The results reveal that the primary and secondary velocities increase with the Hall current. An increase in the ion-slip paxameter also leads to an increase in the primary velocity but a decrease in the secondary velocity. It is also shown that the combined effect of the rotation, Hall, and ion-slip parameters determines the contribution of the secondary motion in the fluid flow.

关键词： magnehydrodynamics (MHD) Couette flow rotating system Hall andion-slip currents accelerated motion

Relativistic treatment of the spin-zero particles subject to the second Pschl Teller-like potential

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Chinese Physics B 2013年第10期22卷 101-106页

作者： Ekele V.Aguda Amos S.Idowu department of mathematics Ahmadu Bello University ZariaNigeria department of mathematics University of IlorinNigeria

The three-dimensional Klein-Gordon equation is solved for the case of equal vector and scalar second Poschl-Teller potential by proper approximation of the centrifugal term within the framework of the asymptotic iteration method. Energy eigenvalues and the corresponding wave function are obtained analytically. Eigenvalues are computed numerically for some values of n and It is found that the results are in good agreement with the findings of other methods for short-range potential.

关键词： second P6schl-Teller potential asymptotic iteration eigenvalues eigenfunction

Phytoremediation Strategies for Heavy Metal Contamination: A Review on Sustainable Approach for Environmental Restoration

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Journal of Environmental Protection 2024年第4期15卷 450-474页

作者： Mariam Salifu Matthew Abu John Murtala Abubakar Ibukunoluwa Abimbola Bankole Nneka Damola Ajayi Olawumi Amusan department of Chemistry and Biochemistry University of Mississippi Olemiss MS USA department of Biochemistry Ahmadu Bello University Zaria Nigeria department of Plant Pathology North Dakota State University Fargo ND USA Directorate of Research and Development Nigerian Institute of Leather and Science Technology (NILEST) Zaria Nigeria department of Chemistry University of Akron Akron OH USA

Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. Heavy metal pollution is mostly produced by urbanization and industry, which threatens ecosystems and human health. Herein, we discuss a sustainable environmental restoration strategy employing phytoremediation for heavy metal pollution, the carcinogenic, mutagenic, and cytotoxic effects of heavy metals such as cadmium, copper, mercury, selenium, zinc, arsenic, chromium, lead, nickel, and silver, which may be fatal. Phytoremediation, which was prioritized, uses plants to remove, accumulate, and depollute pollutants. This eco-friendly method may safely collect, accumulate, and detoxify toxins using plants, making it popular. This study covers phytostabilization, phytodegradation, rhizodegradation, phytoextraction, phytovolatilization, and rhizofiltration. A phytoremediation process’s efficiency in varied environmental circumstances depends on these components’ complex interplay. This paper also introduces developing phytoremediation approaches including microbe-assisted, chemical-assisted, and organic or bio-char use. These advancements attempt to overcome conventional phytoremediation’s limitations, such as limited suitable plant species, location problems, and sluggish remediation. Current research includes machine learning techniques and computer modeling, biostimulation, genetic engineering, bioaugmentation, and hybrid remediation. These front-line solutions show that phytoremediation research is developing towards transdisciplinary efficiency enhancement. We acknowledge phytoremediation’s promise but also its drawbacks, such as site-specific variables, biomass buildup, and sluggish remediation, as well as ongoing research to address them. In conclusion, heavy metal pollution threatens the ecology and public health and must be reduced. Phytoremediation

关键词： Phytoremediation Heavy-Metal Contamination Sustainability Restoration

Unsteady natural convection Couette flow of heat generating/absorbing fluid between vertical parallel plates filled with porous material

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Applied mathematics and Mechanics(English Edition) 2012年第3期33卷 303-314页

作者： B.K.JHA M.K.MUSA department of mathematics Ahmadu Bello UniversityZaria 234Nigeria mathematics Unit School of Basic and Remedial StudiesAhmadu Bello UniversityFuntua 6007Nigeria

The extended Brinkman Darcy model for momentum equations and an energy equation is used to calculate the unsteady natural convection Couette flow of a viscous incompressible heat generating/absorbing fluid in a vertical channel （formed by two infinite vertical and parallel plates） filled with the fluid-saturated porous medium. The flow is triggered by the asymmetric heating and the accelerated motion of one of the bounding plates. The governing equations are simplified by the reasonable dimensionless parameters and solved analytically by the Laplace transform techniques to obtain the closed form solutions of the velocity and temperature profiles. Then, the skin friction and the rate of heat transfer are consequently derived. It is noticed that, at different sections within the vertical channel, the fluid flow and the temperature profiles increase with time, which are both higher near the moving plate. In particular, increasing the gap between the plates increases the velocity and the temperature of the fluid, however, reduces the skin friction and the rate of heat transfer.

关键词： heat generating/absorbing fluid natural convection flow porous material acceleration motion

Entropy generation under the influence of radial magnetic field and viscous dissipation of generalized Couette flow in an annulus

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Propulsion and Power Research 2018年第4期7卷 342-352页

作者： Taiwo S.Yusuf Michael O.Oni department of mathematics Ahmadu Bello UniversityZariaNigeria

This paper investigates the combined effect of radial magnetic field and viscous dissipation on entropy generation in horizontal co-axial cylinders of generalized Couette *** analytical solutions for velocity and temperature profiles are obtained and utilized to compute the entropy generation,Bejan number as well as the average entropy generation *** effect of relevant parameters on temperature field,velocity field,entropy generation,average entropy and Bejan number are portrayed graphically and *** isoflux heating near the inner surface of the fixed outer cylinder with higher dominance in the case of isoflux *** reverse is seen on the moving inner cylinder.

关键词： Radial magnetic field Viscous dissipation Generalized Couette flow Isothermal Isoflux Entropy generation