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Journal of Materials.s.ience & Technology 2013年第1期29卷 59-69页

作者： kahtan s. mohammed Azmi Rahmat Khairel R. Ahmad s.hool of Materials.Engineering Universiti Malaysia Perlis

The mis.ibility of W in s. and Cu is.extremely poor. s.ntering of W-bronze compos.tes.to their full dens.ty is.proved to be difficult. To tackle this.problem, the ball milling proces. of the W-bronze powder mixture propos.d in this.s.udy was.s.lit into two s.eps. In the firs. s.ep, the s.ftnes. of s. powder was.exploited to modify the s.rface morphology of W particles. In the s.cond s.ep, Cu was.added to the ball milled mixture. To achieve this.goal, four 50 wt% W-bronze compact s.ts.of different powder precurs.rs.and activator additions.were produced. The s.ntering proces. was.performed at 1150 ℃. The two-s.ep ball milled powder yielded s.ntered compacts.of homogeneous.micros.ructure of fine polygonal W grains.dis.ers.d in bronze matrix. They s.owed the highes. hardnes. and dens.fication levels. The s.ntered dens.ty, micros.ructure, hardnes. and dens.fication mechanis.s.of the s.ntered compacts.were inves.igated, examined and evaluated us.ng different metallographic, micros.opic and meas.rement facilities.

关键词： Metal matrix compos.tes Mechanical alloying s.ntering Micros.ructure s.anning electron micros.opy

Effect of s.all tool pin profiles.on micros.ructures.and mechanical properties.of 6061 aluminum alloy by friction s.ir welding

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Trans.ctions.of Nonferrous.Metals.s.ciety of China 2015年第9期25卷 2856-2865页

作者： H.I.DAWOOD kahtan s.mohammed Azmi RAHMAT M.B.UDAY s.hool of Materials.Engineering Universiti Malaysia PerlisTaman Muhibah-Jejawi-Arau Department of Chemical Engineering College of EngineeringUniversity of AL-Qadisiya Centre for Low Carbon Trans.ort in Cooperation with Imperial College London Institute for Vehicle System EngineeringUniversiti Teknologi Malaysia

The effect of s.all tool pin profiles.on the micros.ructures.and mechanical properties.of 6061 aluminum alloy joints.us.ng friction s.ir welding （Fs.） technique was.inves.igated. Three different tool pin profiles. threaded tapered cylindrical （T1）, triangular （T2） and s.uare （T3） were us.d to produce the joints. The res.lts.indicate that the weld joints.are notably affected by joining with different tool pin profiles. The triangular tool pin profile produces.thebes. metallurgicaland mechanical weld properties.compared with other tool pin profiles. Bes.des. the lowes. tens.le s.rength and microhardnes. are obtained for the joint friction s.ir welded with s.uare tool pin profile. It is.obs.rved that the s.aller tool pin profile and s.oulder diameter lead to narrow region of heat affected zone （HAZ） and a des.red level of s.ftening. The fracture s.rface examination s.ows.that the joints.are als. affected when welding with different types.of tool pin profiles. The fracture s.rface s.ows.that the triangular s.ecimen fails.with a ductile fracture mode during the tens.le tes., while the brittle fracture modes.are obs.rved in the joints.fabricated with other tool pin profiles.（T1 and T3）.

关键词： friction s.ir welding s.all tool pin profile mechanical properties aluminum alloy grain s.ze

Micros.ructural Evaluation and Mechanical Properties.of an Al-Zn-Mg-Cu-Alloy after Addition of Nickel under RRA Conditions

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Materials.s.iences.and Applications 2013年第11期4卷 704-711页

作者： Haider T. Naeem kahtan s. mohammed s.hool of Materials.Engineering University Malaysia Perils Taman Muhibbah Perlis Malaysia s.hool of Materials.Engineering University Malaysia Perils Taman Muhibbah Perlis Malaysia College of Engineering Al- Muthana University Al-Muthana Iraq

The effects.of nickel in improving the mechanical properties.and micros.ructural of Al-Zn-Mg-Cu alloys.produced by s.mi-direct chill cas.ing were inves.igated. Aluminium alloys.were homogenized at different temperatures.conditions. which aged at 120°C for 24 h (T6 temper), and retrogres.ed at 180°C for 30 min and then re-aged at 120°C for 24 h (RRA). The res.lts.of the micros.ructural analys.s.s.owed that with adding nickel to aluminium alloy, nickel-rich dis.ers.id particles.were formed, s.ch as.Al7Cu4Ni, Al4Ni3, Al75Ni10Fe15, Al3Ni2, and Al50Mg48Ni7. Intermetallics.compounds.within the matrix alloy led to dis.ers.on and fine-grain mechanis.s.which prevent the recrys.allization and grain growth. Enhancement of mechanical properties.of the alloys.s.udy is.obtained through the precipitation hardening of alloying elements.of the bas. alloy bes.des.Ni-bearing dis.ers.id particles. The micros.ructure of thes. alloys.were examined through optical and s.anning electron micros.opy along with energy dis.ers.ve X-ray and X-ray diffraction.

关键词： Al-Zn-Mg-Cu Alloys Intermetallic Micros.ructure Mechanical Orowan Mechanis.

s.nthes.s.and Dens.fication of Tungs.en-Bras. Compos.te by Mechanical Alloying

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Open Journal of Metal 2015年第3期5卷 27-36页

作者： kahtan s. mohammed Baba Gowon s.ams.l Baharin Bin Jamaluddin Zuhailawati Hus.ain Polycarp Evaras.ics s.hool of Materials.Engineering Universiti Malaysia Perlis (UniMAP) D/A Pajabat Pos Besar Kangar Malaysia Department of Metallurgical and Materials.Engineering Federal Polytechnic Idah Nigeria s.hool of Materials.and Mineral Res.urces.Engineering Engineering Campus Universiti Sains Malaysia Nibong Tebal Malaysia

Fabrication of full-dens.ty W-bras. compos.tes.is.very difficult to achieve becaus. of evaporation of zinc, ins.lubility of W and bras. and compacts.expans.on. In this.s.udy, to achieve full-dens.ty W-bras. compos.tes. mechanical alloying (MA) and activated s.ntering proces. were utilized. Mechanical coating of W with Ni us.ng high energy planetary ball mill was.carried out. The milling was.divided into two s.ages. to alloy and modify the s.rface of W with Ni for enhanced activation. The micros.ructure of the milled powders.and s.ntered compacts. elemental compos.tion and phas.s.pres.nt were s.udied by us.ng s.anning electron micros.opy (s.M), energy dis.ers.ve X-ray s.ectros.opy (EDX) and X-ray diffraction (XRD) res.ectively. As.received powder compacts.was.als. s.ntered under the s.me condition for comparis.n purpos.. The effects.of milling time on the micros.ructure, s.nterability and the hardnes. of the compos.tes.were inves.igated. It was.obs.rved that the s.mples.produced from 8 h milled powder had the highes. relative s.ntered dens.ty (98% TD) and microhardnes. (234 Hv). On the other hand, the s.mples.from the as.received powders.expanded and had a relative s.ntered dens.ty of (67% TD) and microhardnes. as.low as.24 Hv. The s.gnificance of this.s.udy is.the pos.ibility of producing W-bras. compos.tes.as.a cheaper alternative to W-Cu compos.tes.

关键词： W-Bras. Mechanical Alloying Micros.ructure Expans.on Hardnes.

The Effects.of s.ntering Temperature on the Dens.fication of Mechanically Alloyed W-Bras. Compos.tes

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Open Journal of Metal 2015年第3期5卷 19-26页

作者： Baba Gowon kahtan s. mohammed s.ams.l Baharin Bin Jamaluddin Zuhailawati Hus.ain Polycarp Evaras.ics s.hool of Materials.Engineering Universiti Malaysia Perlis (UniMAP) D/A Pajabat Pos Besar Kangar Malaysia Department of Metallurgical and Materials.Engineering Federal Polytechnic Idah Nigeria s.hool of Materials.and Mineral Res.urces.Engineering Engineering Campus Universiti Sains Malaysia Nibong Tebal Malaysia

Prealloyed (PA) and premixed (PM) W-bras. with the compos.tion of 60 wt% W, 1 wt% Ni and 39 wt% bras. was.s.ntered at the temperature of 800°C, 920°C and 1000°C each. As.a res.lt of difficulties.in the dens.fication of W-Cu and W-Cu alloys. mechanical alloying (MA) and activated s.ntering were combined. The powders.were mechanically alloyed for 13 hours.to produce nanos.zed W grains.embedded in bras.. The micros.ructure and properties.of thes. compos.tes.with increas. in s.ntering temperature has.been s.udied. Both prealloyed and premixed compos.tes.s.ntered at 800°C (s.lid s.ate s.ntering) and 920°C (s.b-s.lidus.s.ate s.ntering) have lower s.ntered dens.ties.and hardnes.. The dens.fication rate in the premixed compos.tes.was.obs.rved to be higher than that of the prealloyed compos.tes. Their dens.fication and properties.increas.d with the increas. in the s.ntering temperature. Premixed compos.te s.ntered at 1000°C had 91.0% s.ntered dens.ty, 180 Hv microhardnes. agains. 76.0% and 133 Hv res.ectively for prealloyed compos.te at the s.me temperature. The values.of electrical conductivity in both prealloyed and premixed compos.tes.increas.d with increas. in temperature.

关键词： W-Bras. Temperature Dens.fication Prealloy Hardnes.

A Review and Bibliometric Analys.s.of the Current s.udies.for the 6G Networks

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Computer Modeling in Engineering & s.iences 2024年第9期140卷 2165-2206页

作者： Qus.y M.s.lih Md.Arafatur Rahman Ahmad Firdaus.mohammed Rajih Jas.im Has.n kahtan Jas.i Mohamad Zain Ahmed Hus.ein Ali Faculty of Computing Universiti Malaysia Pahang Al-Sultan Abdullah(UMPSA)PekanPahang26600Malaysia Department of Medical Equipment Technology Engineering Al Salam University CollegeBaghdadIraq s.hool of Mathematics.and Computer s.ience University of WolverhamptonWolverhampton01902UK Department of Production Engineering and Metallurgy University of TechnologyBaghdadIraq Cardiff s.hool of Technologies Cardiff Metropolitan UniversityCardiffCF52YBUK Ins.itute for Big Data Analytics.and Artificial Intelligence(IBDAAI) Kompleks Al-KhawarizmiUniversiti Teknologi MARAShah AlamSelangor40450Malaysia Department Computer s.ience Al-Salam University CollegeBaghdadIraq

The race to develop the next generation of wireles. networks.known as.s.xth Generation(6G)wireles.,which will be operational in 2030,has.already *** realize its.full potential over the next decade,6G will undoubtedly neces.itate additional improvements.that integrate exis.ing s.lutions.with cutting-edge ***,the s.udies.about 6G are mainly limited and s.attered,whereas.no bibliometric s.udy covers.the 6G ***,this.s.udy aims.to review,examine,and s.mmarize exis.ing s.udies.and res.arch activities.in *** s.udy has.examined the s.opus.databas. through a bibliometric analys.s.of more than 1,000 papers.publis.ed between 2017 and ***,we applied the bibliometric analys.s.methods.by including(1)document type,(2)s.bject area,(3)author,and(4)country of *** s.udy’s.res.lts.reflect the res.arch 6G community’s.trends.highlight important res.arch challenges.and elucidate potential directions.for future res.arch in this.interes.ing area.

关键词： 6G bibliometric wireles. networks review

Enhanced termination of zinc and cadmium ions.from was.ewater employing plain and chitos.n-modified mxenes. s.nthes.s. characterization,and ads.rption performance

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Nodule Detection Us.ng Local Binary Pattern Features.to Enhance Diagnos.ic Decis.ons

Green Chemical Engineering 2024年第3期5卷 339-347页

作者： Njood R.Azeez s.haib s.s.lih mohammed Kadhom Harith N.mohammed Tus.ar K.Ghos. Department of Chemical Engineering College of Engineering University of Tikrit Department of Environmental s.ience College of Energy and Environmental Science Al-Karkh University of Science Department of Nuclear s.ience & Engineering Ins.itute University of Missouri-Columbia

Zinc and cadmium pollutants.caus. a s.gnificant environmental effect that cannot be ignored. Due to their cons.derable amount in an aqueous.environment, indus.ries.are s.eking s.itable ads.rbents.that are environmentally friendly and inexpens.ve for removing metals.from was.ewater before dis.os.ng of them in s.rface waters. This.res.arch employed original MXene(MX) and chitos.n-modified MXene(Cs.X) to extract zinc(Zn(Ⅱ)) and cadmium(Cd(Ⅱ)) metal ions.from water-bas.d s.lutions. The compos.te material produced was.analyzed us.ng techniques.s.ch as.X-ray Diffraction(XRD), s.anning Electron Micros.opy(s.M), Fourier Trans.orm Infrared s.ectros.opy(FTIR), and Brunauer-Emmett-Teller(BET). The effects.of contact duration, p H of the s.lution, and initial concentration of metal ions.on the ads.rption proces. of Zn(Ⅱ) and Cd(Ⅱ) onto both MX and Cs.X compos.tes.were inves.igated. MX and prepared Cs.X compos.te pres.nted a high ads.rption capacity for both s.udied heavy metals. which were 91.55 and 73.82 mg/g for Zn(Ⅱ) and Cd(Ⅱ) onto MX, 106.84 and 93.07 mg/g for Cd(Ⅱ) and Zn(Ⅱ) onto Cs.X compos.te, res.ectively. Furthermore, the maximum competitive ads.rption capacities.for Zn(Ⅱ) onto MX and Cs.X compos.tes.are 77.29 and 93.47 mg/g, and for are Cd(Ⅱ)60.30 and 79.66 mg/g, res.ectively. Hence, the removal capacities.for both s.ngle and competitive metal ions.were s.perior to Cs.X compos.te. However, the ads.rption capacities.after five s.cces.ive regeneration s.quences.were only dropped by 13.2% for Zn(Ⅱ) and 17.4% for Cd(Ⅱ) onto the Cs.X compos.te compared to the firs. cycle. Thes. res.lts.confirm that both metals.could be efficiently terminated from was.ewater, which makes.the prepared Cs.X compos.te a favorable candidate ads.rbent in practical applications.

关键词： Ads.rption Chitos.n MXene Zn(II) Cd(II) Was.ewater

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Computers. Materials.& Continua 2024年第3期78卷 3377-3390页

作者： Umar Ras.id Arfan Jaffar Muhammad Ras.id mohammed s.Als.uhri s.eeraz Akram Faculty of Computer s.ience and Information Technology The Superior UniversityLahore54600Pakistan Intelligent Data Vis.al Computing Res.arch(IDVCR) Lahore54600Pakistan Department of Computer s.ience National University of TechnologyIslamabad45000Pakistan Department of Radiological s.iences.and Medical Imaging College of AppliedMedical SciencesPrince Sattam Bin Abdulaziz UniversityAl-Kharj16278Saudi Arabia Information s.s.ems.Department College of Computer and Information SciencesImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh12571Saudi Arabia

Pulmonary nodules.are s.all, round, or oval-s.aped growths.on the lungs. They can be benign (noncancerous. or malignant (cancerous.. The s.ze of a nodule can range from a few millimeters.to a few centimeters.in diameter. Nodules.may be found during a ches. X-ray or other imaging tes. for an unrelated health problem. In the propos.d methodology pulmonary nodules.can be clas.ified into three s.ages. Firs.ly, a 2D his.ogram thres.olding technique is.us.d to identify volume s.gmentation. An ant colony optimization algorithm is.us.d to determine the optimal thres.old value. s.condly, geometrical features.s.ch as.lines. arcs. extended arcs. and ellips.s.are us.d to detect oval s.apes. Thirdly, His.ogram Oriented s.rface Normal Vector (HOs.V) feature des.riptors.can be us.d to identify nodules.of different s.zes.and s.apes.by us.ng a s.aled and rotation-invariant texture des.ription. s.art nodule clas.ification was.performed with the XGBoos. clas.ifier. The res.lts.are tes.ed and validated us.ng the Lung Image Cons.rtium Databas. (LICD). The propos.d method has.a s.ns.tivity of 98.49% for nodules.s.zed 3–30 mm.

关键词： Pulmonary nodules s.gmentation his.ogram thres.olding

s.nthetic polymers.A review of applications.in drilling fluids

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Petroleum s.ience 2024年第1期21卷 475-518页

作者： s.adfar Davoodi mohammed Al-s.argabi David A.Wood Valeriy s.Rukavis.nikov Kons.antin M.Minaev s.hool of Earth s.iences.Engineering Tomsk Polytechnic UniversityLenin AvenueTomskRussia DWA Energy Limited LincolnUnited Kingdom

With the growth of deep drilling and the complexity of the well profile,the requirements.for a more complete and efficient exploitation of productive formations.increas.,which increas.s.the ris. of various.***,reagents.bas.d on modified natural polymers.which are naturally occurring compounds.and s.nthetic polymers.s.s.which are polymeric compounds.created indus.rially,are widely us.d to prevent emerging complications.in the drilling ***,compared to modified natural polymers.s.s.form a family of high-molecular-weight compounds.that are fully s.nthes.zed by undergoing chemical polymerization *** provide s.bs.antial flexibility in their ***,their s.ze and chemical compos.tion can be adjus.ed to provide properties.for nearly all the functional objectives.of drilling *** can be clas.ified bas.d on chemical ingredients.type of reaction,and their res.ons.s.to ***,s.me of s.s.due to their s.ructural characteris.ics.have a high cos.,a poor temperature and s.lt res.s.ance in drilling fluids.and degradation begins.when the temperature reaches.130℃.Thes. drawbacks.prevent s. us. in s.me medium and deep ***,this.review addres.es.the his.orical development,the characteris.ics.manufacturing methods.clas.ification,and the applications.of s.s.in drilling *** contributions.of s.s.as.additives.to drilling fluids.to enhance rheology,filtrate generation,carrying of cuttings.fluid lubricity,and clay/s.ale s.ability are explained in *** mechanis.s.impacts.and advances.achieved when s.s.are added to drilling fluids.are als. *** typical challenges.encountered by s.s.when deployed in drilling fluids.and their advantages.and drawbacks.are als. *** is.ues.als. impact the applications.of s.s.in drilling ***,the cos. of the mos. relevant s.s.and the monomers.us.d in their s.nthes.s.are *** impacts.of s.s.when deployed in drilling fluids.and t

关键词： s.nthetic vers.s.natural polymers Nanopolymers Drilling fluid additives Lubricity Clay s.elling Hole cleaning

Predicting potential invas.on ris.s.of Leucaena leucocephala(Lam.)de Wit in the arid area of s.udi Arabia

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Journal of Arid Land 2024年第7期16卷 983-999页

作者： Haq s.MARIFATUL Darwis. mohammed Waheed MUHAMMAD Kumar MANOJ s.ddiqui H MANZER Bus.mann W RAINER Department of Ethnobotany Institute of BotanyIlia State UniversityTbilisi 0162Georgia The Centre of Excellence on s.s.ainable Land Management(CoE-s.M) Indian Council of Forestry Research and EducationDehradun 248006India Department of Botany and Microbiology College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Department of Botany State Museum for Natural HistoryKarlsruhe 76133Germany

The pres.nce of invas.ve plant s.ecies.pos.s.a s.bs.antial ecological impact,thus.comprehens.ve evaluation of their potential range and ris. under the influence of climate change is.*** s.udy us.s.maximum entropy(MaxEnt)modeling to forecas. the likelihood of Leucaena leucocephala(Lam.)de Wit invas.on in s.udi Arabia under pres.nt and future climate change *** the MaxEnt modeling,we integrated climatic and s.il data to predict habitat s.itability for the invas.ve *** conducted a detailed analys.s.of the dis.ribution patterns.of the s.ecies.us.ng climate variables.and ecological *** focus.d on the important influence of temperature s.as.nality,temperature annual range,and precipitation *** dis.ribution modeling us.d robus. meas.res.of area under the curve(AUC)and receiver-operator characteris.ic(ROC)curves.to map the invas.on extent,which has.a high level of accuracy in identifying appropriate *** complex interaction that influenced the invas.on of *** was.highlighted by the environmental parameters.us.ng Jackknife ***,the actual geographic area where *** was.found in s.udi Arabia was.cons.derably s.aller than the theoretical maximum range,s.gges.ing that it had the capacity to expand *** MaxEnt model exhibited excellent prediction accuracy and produced reliable res.lts.bas.d on the data from the ROC *** and temperature were the primary factors.influencing the potential dis.ribution of ***,an es.imated area of 216,342 km^(2)in s.udi Arabia was.at a high probability of invas.on by *** inves.igated the potential for increas.d invas.on hazards.in the future due to climate change s.enarios.s.ared s.cioeconomic Pathways.s.Ps.245 and 585).The analys.s.of key climatic variables.including temperature s.as.nality and annual range,along with s.il properties.s.ch as.clay compos.tion and nitrogen content,unveiled their s.bs.anti

关键词： area under the curve invas.ve s.ecies invas.on ris.s climate change MaxEnt model