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Chinese Physics B 2016年第2期25卷 496-503页

作者： I.Ahmad m.j.akhtar m.Siddique Department of metallurgy and materials Engineering PIEAS Physics Division PINSTECH

Nd Fe_（1-x）Ni_xO_3（0.1 ≤ x ≤ 0.7） orthoferrites are synthesized by solid state reaction method, and the structural properties of these materials are investigated by employing x-ray diffraction（XRD）, scanning electron microscopy（SEm） and m o¨ssbauer spectroscopy. The orthorhombic structure is observed in all systems; however, with the increase in Ni doping,the increase in tolerance factor and the decrease in the cell volume are observed. Orthorhombic distortion decreases with Ni content increasing up to 50%, while above 50% Ni doping it increases. SEm examination indicates the increases in grain size and intermixing of grains with increase in Ni concentration. Comparison between bulk and theoretical densities shows that in each of all samples porosity is less than 2%. m？ssbauer spectroscopic investigations are performed to explain local structure, Fe oxidation states and collapse of the magnetic ordering. In these samples the Fe oxidation state remains＋3 and there is no considerable increase in hole states observed; however due to mismatch of the ionic radii between Fe^（3＋） and Ni^（3＋）, octahedral distortions, sagging and distribution of hyperfine parameters increase with increase in Ni concentration. The major factors behind the collapse of magnetic ordering in the Ni-doped systems are the weakening of the super-exchange interactions, decrease in the Neel temperature, increase in spin–spin relaxation frequency and high spin to low spin transition.

关键词： ceramic crystal structure electron microscopy mossbauer spectroscopy

Scrum Adoption,Acceptance and Implementation(A Case Study of Barriers in Pakistan's IT Industry and mandatory Improvements)

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Scrum Adoption,Acceptance and Implementation(A Case Study of...

Interatomic Potentials for Some Binary Oxides

第17届工业工程与工程管理国际学术会议(IE&Em2010)

作者： m.j.akhtar A.Ahsan W.Z.Sadiq Department of Engineering management Center for Advanced Studies in EngineeringIslamabadPakistan

Pakistan's software industry is comparatively young as compared to the global software *** aspect makes this young industry flexible to adopt new project management and software development methodologies because the existing methodologies are not mature enough therefore any new change does not impose serious threats and / or risks to existing operational working *** is a project management approach and is most commonly adopted in the global industry today and Pakistan's software industry is also adopting Scrum for acquiring utmost benefit from this *** primary rationale of this paper is to get an insight into Scrum adoption,implementation and acceptance in Pakistan's software *** purpose is also to understand how much Scrum is feasible;particularly for Pakistan's software *** derived from this research effort would be helpful for overall Pakistan's software industry for making an accurate decision for Scrum adoption,implementation and acceptance.

关键词： Scrum Software Project management

来源： cnki会议评论

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journal of materials Science & Technology 2001年第6期17卷 638-642页

作者： m.Nadeem, m.j.akhtar, R.Shaheen and m.N.Haque Nuclear Physics Division, Pakistan Institute of Nuclear Science and Technology, P.O. Nilore, Islamabad, Pakistan A.Y.Khan Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan Inst Nucl Sci & Technol Div Nucl Phys Islamabad Pakistan

Using atomistic computer simulation methods we have derived a new set of interatomic potential parameters for some binary oxides, comprising divalent transition elements (rock-salt structured) and tetravalent metals. Computational techniques based on the minimization of the crystal energy with respect to atomic coordinates have been employed. Crystal properties were calculated and compared with the experimental data to check the reliability of our potential models. Intrinsic (Schottky and Frenkel) defect energies were also calculated and compared with previous studies. There is a good agreement between these calculations, which shows that the new potential parameters are reliable and can be used with confidence for future investigations.

关键词： constants Frenkel derivation coordinates struc divalent Faraday ionic fitting dipole

Lubrication effectiveness of composite lubricants during P/m electrostatic die wall lubrication and warm compaction

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journal of University of Science and Technology Beijing 2006年第6期13卷 528-531页

作者： Farid akhtar materials Science and Engineering School University of Science and Technology BeijingBeijing 100083China

The lubrication effectiveness of the composite lubricants, 50wt% ethylene bis-stearamide （EBS） wax ＋50wt% graphite and 50wt% EBS wax ＋ 50wt% BN, during the powder metallurgy （P/m） electrostatic die wall lubrication and warm compaction was studied. The results show that the combination of 50wt% EBS wax and 50wt% graphite has excellent lubrication performance, resulting in fairly high green densities, but the mixture of 50wt% EBS wax and 50wt% BN has less beneficial effect. In addition, corresponding die temperatures should be applied when different die wall lubricants are used to achieve the highest green densities.

关键词： powder metallurgy composite lubricant electrostatic die wall lubrication warm compaction

Brain-penetrating neurotrophic factor mimetics: HER-096 as a disease-modifying therapy for Parkinson’s disease

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Neural Regeneration Research 2025年第4期20卷 1094-1095页

作者： Natalia Kulesskaya Kira m.Holmström Henri j.Huttunen Herantis Pharma Plc EspooFinland

Neurotrophic factors as a therapeutic approach in neurodegenerative diseases:A major unmet need in the field of central nervous system diseases is disease-modifying *** for decades there have been various symptomatic treatments available to alleviate the symptoms of the disease,disease-modification,*** that stop,significantly delay,or reverse the progression of the disease,has been turned out to a difficult goal to achieve.

关键词： diseases treatment therapeutic

Particle Size Distribution and Characterization of High Siliceous and microporous materials

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journal of materials Science & Technology 2005年第4期21卷 563-570页

作者： S.KDurrani j.akhtar m.Ahmad m.j.moughal Nuclear materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamabad PakistanNuclear Materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamabad PakistanNuclear Physics Divisions Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamaad PakistanNuclear Materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore. Islamabad. Pakistan

Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate （SAPO） microporous materials. A comparative study was furnished for measuring surface characteristics, particle size and particle size distribution using particle size analyzer （PSA） and scanning electron microscope （SEm）. The PSA is capable of measuring particle diameter in micron range. The results of these techniques for estimation of particle size were compared and correlated statistically. Student t-test and variance ratio test （F-test） methods were performed for the significance of results by the analysis of variance （ANONA） and multiple-range tests. Textural and surface characteristics were evaluated by Brunauer, Emmett ＆ Teller （BET） volumetric technique and v-αs plotting method. The textural results shows that the external surface area and micropore volume of microporous materials were higher than those of the high siliceous zeolites and its zeotype materials.

关键词： Synthesis High siliceous zeolites microporous materials Particle size distribution micropore volume SEm

Systematic study of Ce^(3+) on the structural and magnetic properties of Cu nanosized ferrites for potential applications

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journal of Rare Earths 2018年第2期36卷 156-164页

作者： majid Niaz akhtar A.B.Sulong m.N.akhtar muhammad Azhar Khan Department of Physics Muhammad Nawaz Sharif University of Engineering and Technology (MNSUET) Department of mechanical and materials Engineering Faculty of Engineering and Built Environment Universiti Kebangsaan Malaysia (UKM) Institute of Pure and Applied Biology Department of ZoologyBahaudin Zakariya University Department of Physics The Islamia University of Bahawalpur

Ce^（3＋） substituted Cu-spinel nanoferrites CuCe_xFe_（2-x）O_4（x=0.00, 0.02, 0.04, 0.06, 0.08 and 0.10） were synthesized via sol-gel self-combustion hybrid route. Single phase spinel ferrite of Cu nanoferrites were examined using X-ray diffraction（XRD） analysis whereas the multiphase structure was observed as Ce contents increased from x=0.06. Field emission scanning electron microscopy（FESEm）, Thermogravimetric and differential thermal analysis（TGA and DTA） and Fourier transform infrared spectroscopy（FTIR） were used to find out the morphology phase and metal stretching vibrations of Ce^（3＋） substituted nanocrystalline ferrites. The crystallite size was increased and found in the range of 25-91 nm. The agglomerations in Cu ferrite samples increase as the Ce^（3＋） concentration increases. The magnetic properties such as remanence, saturation magnetization, coercivity, Bohr magneton and magnetocrystalline anisotropy constant（K） were determined using m-H loops recorded from a vibrating sample magnetometer（VSm）. Saturation magnetization, remanence and coercivity are increased as the Ce^（3＋）contents increase in Cu nanocrystalline samples. moreover, law of approach to saturation（LoA） was used to calculate the maximum value of saturation for Ce-doped Cu nanoferrites. The soft magnetic behaviour of the Cu nanoferrite is observed as compared to the samples substituted with the increased Ce contents in Cu nanocrystalline ferrite. Bohr magneton and magnetocrystalline anisotropy are found to increase with the substitution of rare earth Ce^（3＋） contents in Cu spinel nanocrystalline ferrite. Cedoped Cu nanocrystalline ferrites with excellent properties may be suitable for potential applications in sensing, security, switching, core, multilayer chip inductor, biomedical and microwave absorption applications.

关键词： Ce-doped Cu nanocrystalline ferrites X-ray diffraction(XRD) Scanning electron microscopy(SEm) Transmission electron microscopy(TEm) Fourier transform infrared(FTIR) Vibrating sample magnetometer(VSm)

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert j.Thomas m.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

EFFECT OF GAmmA RAYS IN THE PREPARATION OF POLYmER AND HYDROGEL FROm ACRYLAmIDE mONOmER

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Chinese journal of Polymer Science 2003年第4期21卷 437-442页

作者： m.m.Alam m.F.mina F.akhtar NRCD INST AERE GPO Box-3787 Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh

The formation of polymer and hydrogel from aqueous solutions having 20, 30 and 40% concentrations ofacrylamide monomer by γ-ray irradiation processing in the dose range 0.06-30 kGy using a Co-60 source and theircharacterization have been observed. Polymer conversion and gel fraction are found to depend on radiation doses. Polymerconversion increases with the increase of dose, depending on the solution concentration, where maximum conversion isachieved at 0.18, 0.16 and 0.10 kGy for 20%, 30% and 40% concentrations, respectively. On the other hand, gel fractionincreases with dose from the gel point (0.12 kGy) for all concentrations, where 100% conversion of gel occurs at doses≥5 kGy. Tensile strength, viscosity and molecular weight (m_w) of polymer samples increase with both the dose and theconcentration, showing a high value of m_w up to≈10~8. Swelling of hydrogels under water with respect to time varies due tothe variation of cross-linking density formed in the gels and the maximum swelling mainly occurs within 24 h. A remarkable change of surface morphology reveals characteristic features of monomer, polymer and hydrogel films.

关键词： Polymer Hydrogel γ-Radiation Cross-linking Swelling

Effect of inner oxidant on self-propagating high-temperature synthesis of mnZn-ferrite powder

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Rare metals 2006年第Z1期25卷 553-556页

作者： akhtar Farid School of materials Science and Engineering University of Science and Technology Beijing

Using KClO3 as an inner oxidant, mnZn-ferrite powder was synthesized by a self-propagating high-temperature synthesis (SHS) process in normal air atmosphere. The effects of the inner oxidant on combustion temperature, combustion velocity, microstructure and the phase of the product were investigated by XRD and SEm,respectively. The results show that a highly ferritized powder can be obtained as well as the highest combustion temperature and the highest combustion velocity when the inner oxidant content m equals 54(k-16).

关键词： inner oxidant self-propagating high-temperature synthesis (SHS) mnZn-ferrite powder