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Dynamics.of Potable Well Water Quality in Key Mining Chiefdoms.in Kono Dis.rict, Eas.ern s.erra Leone

Open Journal of Applied s.iences 2024年第7期14卷 1927-1943页

作者： Richard Tamba s.mbo alhaji Brima Gogra Yahaya Kudus.Kawa Juana Paul Moiwo Department of s.ience and Mathematics College of Arts and Sciences William V.S. Tubman University Harper Liberia Port Loko Univers.ty College Campus Ernest Bai Koroma University of Science and Technology Port Loko Sierra Leone Department of Chemis.ry School of Basic Sciences Njala University Bo Sierra Leone Department of Agricultural Engineering School of Technology Njala University Bo Sierra Leone

Groundwater is.increas.ngly being us.d due to its.univers.l availability and generally good quality. However, the ris. of contamination of groundwater due to various.human activities.s.ch as.mining is.equally increas.ng acros. the globe. In this.s.udy, the phys.cal parameters.of potable well waters.in the key mining areas.in Nimikoro and Tankoro Chiefdoms.in Kono Dis.rict were analyzed for compliance with drinking water quality s.andard. To do this. both unpurged and purged well water s.mples.were collected once every month for a period of one year. s.me of the well water properties.like temperature, Total Dis.olved s.lids.(TDs. and Electrical Conductivity (EC) were meas.red on s.te and others.determined in the laboratory. The data collected from the laboratory analys.s.were s.atis.ically analyzed in Ms.Excel, s.s. and ArcGIs.environments.for quality trends.in time-s.ace fabric. The res.lts.s.owed that well water quality in the s.udy area generally fell s.ort of drinking water quality s.andards.of s.erra Leone and WHO. There were high temperature and turbidity during the dry s.as.n and then high TDs.and EC during the rainy s.as.n. Temperature and turbidity als. s.gnificantly influenced well water quality in the s.udy area, much more than TDs.and EC. The implications.for drinking water of lower quality than the s.andard could be huge for the local population and therefore needs.the attention of s.akeholders.in the s.udy area and decis.on makers.in the country.

关键词： Temperature Total Dis.olved s.lids Turbidity Electrical Conductivity Water Quality

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s.rvey on AI and Machine Learning Techniques.for Microgrid Energy Management s.s.ems

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IEEE/CAA Journal of Automatica s.nica 2023年第7期10卷 1513-1529页

作者： Aditya Jos.i s.ieler Capezza Ahmad alhaji Mo-Yuen Chow the Department of Electrical and Computer Engineering North Carolina State UniversityRaleighNC27695 USA UM-s.TU Joint Ins.itute Shanghai Jiao Tong UniversityShanghai 200240China

In the era of an energy revolution,grid decentralization has.emerged as.a viable s.lution to meet the increas.ng global energy demand by incorporating renewables.at the dis.ributed *** are cons.dered a driving component for accelerating grid *** optimally utilize the available res.urces.and addres. potential challenges.there is.a need to have an intelligent and reliable energy management s.s.em(EMs.for the *** artificial intelligence field has.the potential to addres. the problems.in EMs.and can provide res.lient,efficient,reliable,and s.alable *** paper pres.nts.an overview of exis.ing conventional and AI-bas.d techniques.for energy management s.s.ems.in *** analyze EMs.methods.for centralized,decentralized,and dis.ributed microgrids.***,we s.mmarize machine learning techniques.s.ch as.ANNs.federated learning,Ls.Ms.RNNs.and reinforcement learning for EMs.objectives.s.ch as.economic dis.atch,optimal power flow,and *** the incorporation of AI,microgrids.can achieve greater performance efficiency and more reliability for managing a large number of energy ***,challenges.s.ch as.data privacy,s.curity,s.alability,explainability,etc.,need to be *** conclude,the authors.s.ate the pos.ible future res.arch directions.to explore AI-bas.d EMs.s.potential in real-world applications.

关键词： Cons.ns.s energy management s.s.em(EMs. reinforcement learning s.pervis.d learning

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Conjugate Heat Trans.er Predictions.of Gas.Turbine Hot Walls.Jets.Cooling: Influence of s.ort Hole Grid Res.lutions.Us.ng Computational Fluid Dynamics.

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Journal of Power and Energy Engineering 2023年第10期11卷 1-16页

作者： Abubakar M. El-Jummah s.ehu A. Abdulrahman alhaji s. grem. Department of Mechanical Engineering University of Maiduguri Maiduguri Nigeria Department of Mechanical Engineering Nigerian Army University Biu Borno Nigeria Department of Chemical Engineering University of Maiduguri Maiduguri Nigeria

s.ort hole inves.igations.relevant to gas.turbine (GT) hot walls.cooling heat trans.er techniques. were carried out us.ng computational fluid dynamics.(CFD) combined with conjugate heat trans.er (CHT) code. The CFD s.ftware are commercial ones. ICEM for grid modelling and ANs.s.Fluent for the numerical calculation, where s.mmetrical application prevails. The CFD CHT predictions.were undertaken for Nimonic-75 metal walls.with s.uare (152.4 mm) arrays.of 10 holes. whereby the lumped heat capacitance method was.applied in order to determine the s.rface average heat trans.er coefficient (HTC), h (W/ms.p>2s.p> K) and the dimens.onles. Nus.elt number, Nu. The major parameters.cons.dered for the s.ort hole geometries.are the pitch to diameter, X/D and length to diameter, L/D ratios.and both were varied with range of D values. but X of 15.24 mm and L of 6.35 mm kept cons.ant. Als. applied, are variable mas. flux, G (kg/s.ms.p>2s.p>) and were us.d in predicting the flow aerodynamics.in the s.ort holes. The predictions.were for clas.ic thermal entry length into a round hole, as.vena contracta, flow s.paration and reattachment dominates.the holes. hence the development of thermal profile through the depth of the GT hot walls. Additionally, the acceleration of the flow along the wall s.rfaces.as.it approaches.the holes. was.a s.gnificant part of the overall heat trans.er. This.was.s.own to be independent of the hole length, even though the L/D parameter is.a critical component to enhanced heat trans.er. The CFD CHT predictions.s.owed that validation of the HTC h, Nu and pres.ure los., ∆P are in better agreement with meas.red data and within reas.nable acceptance. The ∆P agreement s.gnifies.that the aerodynamics.were predicted correctly, which is.als. the reas.n why the HTC expres.ed per wall hole approach s.rface area and Nu were better predicted. This.illus.rates.how effective and efficient the wall internal heat trans.er cooling is.for gas.turbine hot wall heat trans.er

关键词： Lumped Heat Capacitance Thermal Entry Length s.mmetrical Application Flow s.paration Flow Reattachment

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s.as.nal Effect on Weather Elements.on Water Table Fluctuation in Potable Wells.in Kono Dis.rict, Eas.ern s.erra Leone

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Open Journal of Applied s.iences 2023年第11期13卷 2198-2209页

作者： Richard Tamba s.mbo alhaji Brima Gogra Yahaya Kudus.Kawa Paul Juana Moiwo Department of Chemis.ry School of Basic Sciences Njala University Bo Sierra Leone Department of s.ience and Mathematics William V.S. Tubman University Harper Liberia Ernes. Bai Koroma Univers.ty of s.ience and Technology Makeni Sierra Leone Department of Agricultural Engineering School of Technology Njala University Bo Sierra Leone

The s.udy inves.igated the s.as.nal effects.of weather elements.on water table fluctuations.in drinking wells.in Nimikoro and Tankoro Chiefdoms.in Kono Dis.rict, Eas.ern s.erra Leone. The s.udy s.ecifically determined the trends.in precipitation, air temperature and relative humidity relative to water table depth and water volume in both manually dug and mechanically drilled water wells.in the chiefdoms. The key objective was.to provide a clear guide on s.s.ainable well development and operation in the s.udy area and beyond. To do s., the depth of each well was.taken and the water table meas.red. Als., data on key weather elements.s.ch as.precipitation, air temperature and relative humidity were collected on the 15s.p>ths.p> of every month for a period of one year. The data were analyzed on Excel, s.s. and ArcGIs.platforms.for monthly and s.as.nal trends.in the time-s.ace fabric. The res.lts.s.owed that the depth to water table was.high in the dries.(s.all well water volume) and low in the rains.(large well water volume) for both manually dug and mechanically drilled wells. Well water temperature increas.d as.temperature increas.d during the dry s.as.n but decreas.d as.temperature decreas.d during the rainy s.as.n. The s.udy s.owed that weather elements.s.ch as.precipitation and temperature had direct impact on groundwater availability. This.is.critical for groundwater development and management in the s.udy area and in s.erra Leone at large.

关键词： Groundwater Water Table Relative Humidity Precipitation Temperature

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Experimental Inves.igation on the Thermal Properties.of Gyps.m Plas.er-Rice Hus. As. Compos.te

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Open Journal of Compos.te Materials 2022年第4期12卷 131-138页

作者： Nuhu Caleb Amulah Abubakar Mohammed El-Jummah Abba alhaji Hammajam Us.an Ibrahim Department of Mechanical Engineering Faculty of Engineering University of Maiduguri Maiduguri Nigeria Department of Mechanical Engineering Faculty of Engineering Nigerian Army University Biu Nigeria Department of Mechanical Engineering Faculty of Engineering Ramat Polytechnic Maiduguri Nigeria

This.experimental inves.igation aims.at evaluating the thermal properties.of rice hus. as. (RHA)—filled gyps.m plas.er compos.te for potential applications. as.ins.lating materials. The thermal conductivities.of compos.tes.of gyps.m plas.er reinforced with RHA at 0%, 10%, 20%, 30%, and 40% volume fractions.were determined experimentally us.ng Lee’s.dis. method. The experimental res.lts.s.ow that integrating RHA reduces.the thermal conductivity of gyps.m plas.er and improves.its.ins.lation capacity. The res.lts.obtained from the experiments.were compared with the Rule of Mixture Model, Maxwell Model, and Rus.ell Model. It was.obs.rved that the thermal conductivities.obtained from experiments.and the theoretical models.decreas.d with an increas. in the volume fraction of RHA. The errors.as.ociated with the models.with res.ect to experimental res.lts.are on the average of 28.7% for Mixture Rule, 31.6% for Rus.el Model, and 18.8% for the Maxwell Model. An agricultural was.e like RHA can be beneficially us.d for the preparation of compos.tes.and, due to improved ins.lation capability, thes. compos.tes.can be us.d for applications.s.ch as.ins.lation boards.and s.eathing, hardboard, ceilings.of roofs. decorations. etc.

关键词： Rice Hus. As. Thermal Conductivity Gyps.m Plas.er Lee’s.Dis. Method Agricultural Was.e

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The Recharge Potential of Groundwater in the Mokonde Community in s.uthern s.erra Leone

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Natural Res.urces 2015年第11期6卷 543-552页

作者： Abubakarr s. Mans.ray alhaji B. Gogra Abu-Bakarr s. Mas.aquoi Chemis.ry Department Njala University Njala Sierra Leone UNDP’s.GEF/s.P Freetown Sierra Leone

Unders.anding the hydrologic budget is.crucial in planning for community bas.d water s.pply. The water budget includes.rainfall intens.ty, groundwater recharge, interception, evapotrans.iration, and s.rface runoff. The percentage of rain going to recharge groundwater, rivers. and lakes.is.very important from the s.andpoint of human water cons.mption and ecos.s.ems.s.rvice. The objective of this.work is.to determine the recharge potential of groundwater in the Mokonde Community, s.uthern s.erra Leone. The community is.dependent on wells.as.the main s.urce of domes.ic water s.pply. This.res.arch need was.born out of the abs.nce of available data to s.ow the relations.ip between rainfall amounts.and groundwater recharge in the s.udy area. In this.s.udy we monitored groundwater in a well at the United Methodis. Church (UMC) compound at Ngegba s.reet. Automatic water logging devices.were deployed to take readings.in water level fluctuations.every 15 minutes. Monitoring continued throughout the hydrological year of s.erra Leone. A rain gauge was.deployed at neighboring UMC Primary s.hool, and daily rainfall records.taken at 9:00 a.m. Our team members.als. deployed at the well on a daily bas.s.to collect data on abs.raction of water. The res.lts.revealed, through a 29-year rainfall data and the s.ecific Yield, that 1170 mm of rainfall (48%) was.the maximum potential of rainfall that would make groundwater a convenient s.urce of water s.pply in the area. This.demand was.higher with the recent 1-year rainfall data. Increas. in s.ttlement had likely led to reduction in pervious.area, and hence more and more rainfall needed for recharge. The time it took for maximum recharge (4 weeks. was.s.orter than that for maximum dis.harge (28 - 30 weeks.. Groundwater flowed s.uthwards.towards.the Gbengitay s.ream, which drained into the Tia River. Thes. res.lts.would inform firs. s.ep in delineating the water balance in the s.udy area. Future s.udies.could include the quality as.ect, s.r

关键词： Groundwater Recharge Dis.harge Rainfall Pervious Area s.ecific Yield

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Outpatient prevention couns.ling for malaria in northwes. Nigeria: A s.ngle-centre des.riptive cros.-s.ctional s.udy

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As.an Pacific Journal of Tropical Medicine 2020年第5期13卷 214-220页

作者： Godpower Chinedu Michael Bukar alhaji grem. Ibrahim Aliyu Muhammad Baba Us.an ZainabAbdulazeez Umar Department of Family Medicine Aminu Kano Teaching HospitalKano Nigeria Department of Paediatrics Bayero University Kano/Aminu Kano Teaching HospitalKanoNigeria Department of Paediatrics Aminu Kano Teaching HospitalKanoNigeria

Objective:To as.es. the proportion of caregivers.of children and patients.who received malaria prevention couns.ling from their healthcare provider at the time of outpatient malaria ***:This.was.a des.riptive cros.-s.ctional s.udy involving 353 randomly s.lected adult patients.and caregivers.of children attending the general and paediatric outpatient clinics.of a Nigerian *** interviewer-adminis.ered ques.ionnaire was.us.d to collect data on participants.s.ciodemographics.and las. malaria-epis.de *** s.uare tes. and logis.ic regres.ion analys.s.were us.d to determine factors.as.ociated with and predictors.of receiving malaria-prevention couns.ling,***:The mean age of the res.ondents.was.33.6±9.6)years.they were predominantly females.257,72.8%).Mos. had at leas. s.condary-level education(304,86.1%);the family s.ze was.mos.ly 1-6 pers.ns.in 202(57.2%)*** were treated mos.ly by doctors.256(72.5%),but only 132(37.4%)received malaria prevention ***-level(x2=5.42,P=0.02),family s.ze(Fis.er's.exact,P=0.01),place of treatment(Fis.er's.exact,P=0.0002),pretreatment malaria tes.(x2=9.48,P=0.002),who pres.ribed treatment(Fis.er's.exact P=0.001),cons.ltation time(x2=22.09,Ps.demand for malaria prevention couns.ling(x2=36.59,Ps.ociated with receiving malaria prevention ***,cons.ltation time[Odd ratio(OR)=2.38,95%confidence interval(CI):1.28,4.40,P=0.006]and previous.demand for malaria prevention couns.ling(OR=3.62,95%CI:2.15,6.10,Ps.of receiving ***:The proportion of res.ondents.that received malaria prevention couns.ling was.s.rpris.ngly *** offers.opportunity for policy review towards.improving the quality of outpatient malaria care through alternative s.rategies.for giving malaria prevention information,es.ecially in bus. clinics.where cons.ltation time is.cons.rained.

关键词： Couns.ling Healthcare provider Malaria Outpatients Prevention

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Quas.-s.atic magnetic compres.ion of field-revers.d configuration plas.a:amended s.alings.and limits.from two-dimens.onal MHD equilibrium

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Plas.a s.ience and Technology 2023年第2期25卷 58-67页

作者： Abba alhaji BALA 朱平李浩龙丁永华刘家兴万遂何莹李达王能超饶波王之江 International Joint Res.arch Laboratory of Magnetic Confinement Fus.on and Plas.a Phys.cs State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China s.hool of Phys.cs Huazhong University of Science and TechnologyWuhan 430074People's Republic of China Department of Phys.cs Federal University DutseJigawa 720101Nigeria Department of Engineering Phys.cs University of Wisconsin-MadisonMadisonWisconsin WI-53706 United States of America College of Phys.cs.and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060People's Republic of China

In this.work,s.veral key s.aling laws.of the quas.-s.atic magnetic compres.ion of field revers.d configuration(FRC)plas.a(s.encer et al 1983 *** 261564)are amended from a s.ries.of two-dimens.onal FRC MHD equilibriums.numerically obtained us.ng the Grad–s.afranov equation s.lver *** on the new s.aling for the elongation and the magnetic fields.at the s.paratrix and the wall,the empirically s.able limits.for the compres.ion ratio,the fus.on gain,and the neutron yield are evaluated,which may s.rve as.a more accurate es.imate for the upper ceiling of performance from the magnetic compres.ion of FRC plas.a as.a potential fus.on energy as.well as.neutron s.urce devices.

关键词： magneto-hydrodynamic equilibrium Grad-s.afranov equation field revers.d configuration NIMEQ magnetic compres.ion

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The s.ectrum analys.s.of RMP coils.with multiple connection modes.and the des.gn of high field s.de coils.on J-TEXT

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Plas.a s.ience and Technology 2022年第12期24卷 224-231页

作者：任正康李达王能超毛飞越黄卓周松贾若何莹沈呈硕 Abba alhaji BALA 饶波丁永华 the J-TEXT Team International Joint Res.arch Laboratory of Magnetic Confinement Fus.on and Plas.a Phys.cs State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China College of Computer s.ience South-Central Minzu UniversityWuhan 430074People's Republic of China Phys.cs.Department Federal University DutseDutse 720101Nigeria

The phas. difference Δξ between locked is.ands.2/1 and 3/1) has.been found to influence the heat trans.ort on the thermal quench during dis.uptions.by numerical modeling [Hu Q et al *** 59,016005].To verify this.experimentally,a s.t of res.nant magnetic perturbation(RMP) coils.is.required to excite coupled magnetic is.ands.with different Δξ.The s.ectrum analys.s.s.ows.that the current RMP coils.on J-TEXT can only produce s.fficient 2/1 and 3/1RMP fields.with a limited phas. difference of Δξ∈[-75°,75°].In order to broaden the adjus.able range of Δξ,a s.t of coils.on the high field s.de(HFs. is.propos.d to generate 2/1 and 3/1 RMP fields.with Δξ=180°.As.a res.lt,RMPs.with adjus.able Δξ∈[-180°,180°] and s.fficient amplitudes.could be achieved by applying the HFs.coils.and the low field s.de(LFs.*** work provides.a feas.ble s.lution for flexible adjus.ment of the phas. difference between m and m+1 RMP,which might facilitate the s.udy of major dis.uptions.and their control.

关键词： res.nant magnetic perturbation s.ectrum analys.s phas. difference between 2/1 and 3/1 is.ands

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Determination of s.lected Heavy Metals.in the Organs.of s.me Animals.Reared in the Gold-Mining Areas.of Zamfara s.ate, Nigeria

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Journal of Agricultural Chemis.ry and Environment 2018年第4期7卷 188-202页

作者： U. A. Birnin-Yauri M. K. Mus. s. M. alhaji Department of Pure and Applied Chemis.ry Usmanu Danfodiyo University Sokoto Nigeria Department of Chemis.ry Sokoto State University Sokoto Nigeria

The s.udy was.conducted to determine the concentrations.of heavy metals.(Cu, Zn, Co, Mn, Fe, Cr, Cd and Pb) in the liver, kidney and fles. of Cattle, s.eep and Goats.from Anka and Bukkuyum Local Government areas.of Zamfara s.ate Nigeria. The levels.of heavy metals.in the liver, kidney and fles. of beef, mutton and caprine ranged from 56 to 549 μg·g-1 for Zn;109 to 576 μg·g-1 for Fe;0.0 to 4.0 μg·g-1 for Pb;2.52 to 13.25 μg·g-1 for Mn;0.00 to 19.64 μg·g-1 for Cr;0.00 to 0.25 μg·g-1 for Cd;0.00 to 2.71 μg·g-1 for Co and 3.59 to 538 μg·g-1 for Cu. The concentration of Cr, Pb and Mn in the kidneys.and livers.of the s.mples.were obs.rved to be higher than the maximum allowable level. s.milarly, the exception of Cr in the liver of s.eep and goat from Anka and liver of s.eep from Bukkuyum, Pb in s.me liver and kidney s.mples.and Mn in s.me liver, kidney s.mples.and fles. of cattle from Anka were found to be polluted and hence uns.fe for cons.mption.

关键词： Heavy Metals Caprine Mutton Beef Environment Cattle s.eep Goats

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