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TiC-maraging stainless steel composite:microstructure, mechanical and wear properties

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Rare metals 2006年第6期25卷 630-635页

作者： Akhtar farid Khadijah Ali Shah Syed Javid Askari School of material Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Particulate TiC reinforced 17-4PH and 465 maraging stainless steel matrix composites were processed by conventional powder metallurgy （P/m）. TiC-maraging stainless steel composites with theoretical density 〉97% were produced using conventional P/m. The microstructure, and mechanical and wear properties of the composites were evaluated. The microstructure of the composites consisted of （core-rim structure） spherical and semi-spherical TiC particles depending on the wettability of the matrix with TiC particles. In TiC-maraging stainless steel composites, 465 stainless steel binder phase showed good wettability with TiC particles. Some microcracks appeared in the composites, indicating the presence of tensile stresses in the composites produced during sintering. The typical properties, hardness, and bend strength were reported for the composites. After heat treatment and aging, an increase in hardness was observed. The increase in hardness was at- tributed to the aging reaction in maraging stainless steel. The specific wear behavior of the composites strongly depends on the content of TiC particles and their interparticle spacing, and on the heat treatment of the maraging stainless steel.

关键词： TiC-maraging stainless steel composites aging wear powder metallurgy microcracks

Impact of carbimazole combined with vitamin E on testicular injury induced by experimental hyperthyroidism in adult albino rats:oxidative/inflammatory/apoptotic pathways

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Asian Journal of Andrology 2024年第4期26卷 396-401页

作者： Ramadan S hussein moustafa m Eyada Rashad m mostafa Samah m Elaidy Shereen H Elsayed Hany m Saad Department of Dermatology College of Medicine Prince Sattam Bin Abdulaziz UniversityAl-Kharj 16242Saudi Arabia Department of Dermatology Andrology and STDsAssiut Police HospitalAssiut 71525Egypt Department of Dermatology Venereology and AndrologyFaculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Department of Andrology and Sexology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Clinical Pharmacology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Rehabilitation Sciences Faculty of Health and Rehabilitation SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh 12271Saudi Arabia.

Thyroid hormones play essential roles in spermatogenesis,but their effects on infertile males remain poorly *** study aimed to evaluate the impact of combining carbimazole(CBZ)with vitamin E(VE)on testicular injury induced by experimental hyperthyroidism in adult albino rats,focusing on oxidative,inflammatory,and apoptotic *** this experimental study,64 adult male albino Wistar rats were divided into eight groups:Group I(control-untreated),Group II(CBZ-control),Group III(VE-control),Group IV(CBZ+VE-control),Group V(levothyroxine-induced testicular injury),Group VI(levothyroxine+CBZ-treated),Group VII(levothyroxine+VE-treated),and Group VIII(levothyroxine+CBZ+VE-treated).The study was conducted in the Faculty of medicine,Suez Canal University(Ismailia,Egypt).After cervical decapitation,both testes and epididymis were examined histopathologically and *** differences were observed among groups concerning malondialdehyde(mDA),glutathione(GSH),superoxide dismutase(SOD),and catalase(CAT;all Pmerase chain reaction analysis showed significant differences in tumor necrosis factor-α(TNF-α),interleukin-10(IL-10),Bcl-2-associated X protein(BAX),B-cell lymphoma 2 protein(Bcl2),p53,Caspase-3,Caspase-8,Caspase-9,and nuclear factor-kappa B(NF-κB)mRNA levels(all Pminiferous tubules and ***,the Group VIII showed improved spermatogenesis and a decrease in testicular side *** addition of VE to the treatment of hyperthyroid rats with CBZ reduced testicular side effects and seminiferous tubular affection when potentially improving *** research is needed to elucidate the underlying mechanisms fully.

关键词： antithyroid drugs testicular injury thyroid gland vitamin E

Thermal properties and high-temperature ablation of high-entropy (Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating on graphite substrate

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Journal of Advanced Ceramics 2024年第8期13卷 1268-1281页

作者： Ana C.Feltrin Daniel Hedman farid Akhtar Division of materials Science Lulea University of TechnologyLulea 97187Sweden Center for multidimensional Carbon materials(CmCm) Institute for Basic Science(IBS)Ulsan 44919Republic of Korea

An entropy-stabilized multicomponent ultrahigh-temperature ceramic(UHTC)coating,(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2),on a graphite substrate was in-situ sintered by spark plasma sintering(SPs)from constituent transition metal diboride ***(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) coating had a hardness of 31.2±2.1 GPa and resisted 36.9 GPa of stress before delamination,as observed at the *** temperature-dependent thermal properties of the multicomponent diboride(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) were obtained by molecular dynamics(mD)simulations driven by a machine learning force field(mLFF)trained on density functional theory(DFT)*** thermal conductivity,density,heat capacity,and coefficient of thermal expansion obtained by the mD simulations were used in time-dependent thermal stress finite element model(FEm)*** low thermal conductivity(m^(-1)·K^(-1))of the multicomponent diboride coupled with its similar coefficient of thermal expansion to that of graphite indicated that stresses of less than 10 GPa were generated at the interface at high temperatures,and therefore,the coating was mechanically resistant to the thermal stress induced during *** experiments at 220℃ showed that the multicomponent diboride coating was resistant to thermal stresses with no visible cracking or *** ablation mechanisms were mechanical denudation and evaporation of B_(2)O_(5) and light V-Ti oxides,which caused a decrease in the mass and thickness of the coating and resulted in mass and linear ablation rates of-0.51 mg·s^(-1) and -1.38μm·s^(-1),respectively,after 60 *** findings demonstrated the thermal and mechanical stability of multicomponent entropy-stabilized diborides as coatings for carbon materials in engineering components under extreme environments.

关键词： entropy-stabilized diborides ultrahigh temperature ceramics molecular dynamics(mD)simulations density functional theory(DFT) ablation properties

Evaluation of Shell and Tube Heat Exchanger Performance by Using ZnO/Water Nanofluids

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Journal of Harbin Institute of Technology(New Series) 2023年第6期30卷 62-69页

作者： hussein Hayder mohammed Ali Adnan m hussein Kadum mohammed Hussain Allami Barhm mohamad Technical Engineering College/Kirkuk Northern Technical UniversityKirkuk 36001Iraq Computer Engineering Techniques Department Al-Kitab UniversityKirkuk 36001Iraq Department of Petroleum Technology Koya Technical InstituteErbil Polytechnic UniversityErbil 44001Iraq

To examine and investigate the impact of nanofluid on heat exchanger performance,including the total heat transfer,the effect of friction factor,the average Nusselt number,and the thermal efficiency,the output heat transfers of a shell and tube heat exchanger using ZnO nanoparticles suspended in water has been conducted *** governing equations were solved using finite volume techniques and CFD simulations with ANSYS/FLUENT Solver *** nanoparticles volume fractions adopted are 0.2%and 0.35%that used in numerical computations under 200 to 1400 Reynolds numbers *** increasing of temperature is approximately 13%from the bottom to the top of heat exchanger,while the maximum enhancement of Nusselt number is about 10%,19%for volume fractions 0.2%and 0.35%*** elevated values of the friction factor at the volumetric ratios of 0.2%and 0.35%are 0.25%and 0.47%*** findings demonstrate that the performance efficiency of shell and tube heat exchanger is enhanced due to the increase in Nusselt number.

关键词： CFD Reynold number thermal efficiency Nusselt number nanofluid heat exchanger

Search for production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at√s=8 TeV using CmS open data

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Chinese Physics C 2024年第4期48卷 6-13页

作者： Y.mahmoud H.Abdallah m.T.hussein S.Elgammal Centre for theoretical physics The British University in EgyptEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

In this study,we conducted a search for dark matter using a part of the data recorded by the CmS experiment during run-I of the LHC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−*** data were gathered from the CmS open *** matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum *** benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the CmS open *** evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider CmS open data search for new physics dark fermion

Synthesis and evaluation of some new oxazolones and imidazolones as antioxidant additives for Egyptian lubricating oils

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Petroleum Science 2012年第3期9卷 389-399页

作者： Ahmed El-mekabaty Osman m.O.Habib hussein m.Hassan Evelin B.moawad Department of Chemistry Faculty of ScienceMansoura University

Oxazolone derivative 2 was utilized as a key intermediate for synthesis of some new oxazolone and imidazolone derivatives. Reaction of oxazolone derivative 2 with diamines under different conditions afforded the corresponding imidazolone derivatives 3-8, respectively. moreover, oxazolone 2 reacted with some heterocyclic amines in glacial acetic acid giving the corresponding imidazolone derivatives 9-14, respectively. Cyclocondensation of thiosemicarbazide with compound 2 in dry pyridine afforded compound 15. Addition of secondary amines to olefin double bond of compound 2 gave the corresponding addition products 16-19, respectively. michael addition of compound 2 with some active methylene compounds afforded oxazolone derivatives 20-23, respectively. These prepared products were evaluated as antioxidant and corrosion inhibitors for gasoline lubricating oil and compounds 6a-e, 10 and 15 exhibited the highest antioxidant and anticorrosive activities. The effect of concentration of additives was studied to recommend the optimum concentration to be used. The results showed, for additive 15, 0.1 g for 1 L oil was the more effective concentration. measurements for thermal analysis and of surface tension of oil after oxidation were also carried out.

关键词： Oxazolone imidazolone benzoimidazole surface tension thermal stability antioxidant additives.

A review on the rheology of heavy crude oil for pipeline transportation

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Petroleum Research 2021年第2期6卷 116-136页

作者： farid Souas Abdelhamid Safri Abdelbaki Benmounah LEGHYD Laboratory Faculty of Civil EngineeringUniversity of Science and Technology Houari Boumediene(USTHB)Bab EzzouarAlgerAlgeria Research Unit materials Processes and Environment(UR-MPE)Faculty of Engineering ScienceUniversity M’Hamed BougaraBoumerdesAlgeria

Given the combination of rising global energy demand and the decline in conventional crudes, heavycrudes are generally considered to be the future energy resource. In many regions of the world, heavycrude oil must be transported through pipelines from the point of production to storage facilities orrefineries. The transportation of heavy crude oil by pipeline poses serious problems related to the highviscosity and flow difficulties, particularly in cold climates or offshore conditions. Indeed, the viscosity ofcrude oil is an important physical property that influences and controls crude oil flow in *** introduces resistance to movement by causing a shear or frictional force between the fluidparticles and the boundary walls. This high viscosity means that the pumping power requirements forcrude oil in a long-distance pipeline are very high in order to overcome the increasing shear and frictionforces. Therefore, in order to facilitate the pumping of these viscous oils and reduce operating expensesand the negative impact of pressure drops in pipelines during flow and processing, their viscosity mustbe reduced. Various techniques are used to increase pumping efficiency and improve the flow of crude oilthrough the pipeline, which may present logistical, technical or economic disadvantages for a givenapplication. The main ones are the addition of surfactants or polymers, dilution with lighter crudes, useof water as annular fluid, thermal remediation and emulsification with surfactant (O/W). This reviewhighlights the methods currently used to enhance the fluidity of heavy crude oil in pipelines behindrheology improvement, in particular the addition of additives and the use of water and surfactants tocreate a stable emulsion of heavy crude oil in water have been considered.

关键词： Additives Emulsion Heavy crude oil Rheology Viscosity

Preparation of new and novel wave like poly(2-anisidine) zirconium tungstate nanocomposite: Thermal, electrical and ion-selective studies

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Chinese Journal of Chemical Engineering 2019年第2期27卷 459-466页

作者： Anish Khan Aftab Aslam Parwaz Khan mahmoud A.hussein Bernaurdshaw Neppolian Abdullah m.Asiri Chemistry Department King Abdulaziz University Center of Excellence for Advanced materials Research King Abdulaziz University Polymer Chemistry Laboratory Chemistry Department Faculty of Science Assiut University SRm Research Institute SRM University

It is necessary to synthesize new material for the advancements of the technology. In this study, new and novel poly(2-anisidine)@zirconium tungstate(P2A/ZrW_2O_8) was synthesized by simple so-gel method. Physicochemical characterization of P2A/ZrW_2O_8 was done by thermogravimetric analysis(TGA), scanning electron microscopy(SEm), X-ray powder diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), ion exchange and simultaneous four probe dc conductivity studies. The conductivity study revealed its highly semiconducting nature, in the range of 10^(-1)–10^(-2) S·cm^(-1). Ion-exchange capabilities of the composite make it applicable for cation-exchange studies. The result of distribution studies(Kd) revealed its selectivity towards Cd^(2+) compared to other metal ions. This property of the composite was utilized for designing Cd^(2+) selective membrane electrode. Several important physical parameters of the ion-selective electrode were determined, such as Nernstian slope(32.32 mV·decade^(-1)), working pH range was 2.0–4.0 and response time was found ～ 17 *** analytical utility of this wave like composite membrane electrode was as, indicator electrode in various potentiometric titrations.

关键词： Conducting polymers Electrochemistry Ion-exchangers Electrode Cd^2+ Poly(2-anisidine)

Sintering behavior, microstructure and properties of TiC-FeCr hard alloy

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Journal of University of Science and Technology Beijing 2007年第1期14卷 89-93页

作者： farid Akhtar Shiju Guo Jawid Askari Jianjun Tian materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Department of metallurgical and malerials Engineering University of Engineering and Technology Lahore Pakistan

TiC based cermets were produced with FeCr, as a binder, by conventional P/m （powder metallurgy） to near 〉97% of the theoretical density. Sintering temperature significantly affects the mechanical properties of the composite. The sintering temperature of 〉1360℃ caused severe chemical reaction between TiC particles and the binder phase. In the TiC-FeCr cermets, the mechanical properties did not vary linearly with the carbide content. Optimum mechanical properties were found in the composite containing 57wt% TiC reinforcement, when sintered at 1360℃ for 1 h. Use of carbon as an additive enhanced the mechanical properties of the composites. Cermets containing carbon as an additive with 49wt% TiC exhibited attractive mechanical properties. The microstructure of the developed composite contained less or no debonding, representing good wettabifity of the binder with TiC particles. Homogeneous distribution of the TiC particles ensured the presence of isotropic mechanical properties and homogeneous distribution of stresses in the composite. Preliminary experiments for evaluation of the oxidation resistance of FeCr bonded TiC cermets indicate that they are more resistant than WC-Co hardmetals.

关键词： powder technology hard alloy sintering reinforcement mechanical property