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Chinese Physics B 2015年第11期24卷 478-482页

作者： M.A.hadi M.A.Alam M.Roknuzzaman M.T.Nasir A.K.M.A.Islam s.h.naqib Department of Physics University of Rajshahi Department of Physics Rajshahi University of Engineering and Technology Department of Physics Jessore University of Science and Technology International Islamic University Chittagong

The structural, elastic, and electronic properties of the very recently discovered ternary silicide superconductor, Li2Irsi3, are calculated using an ab-initio technique. We adopt the plane-wave pseudopotential approach within the frame- work of the first-principles density functional theory （DFT） implemented by the CAsTEP code. The calculated structural parameters show reasonable agreement with the experimental results. The elastic moduli of this interesting material are calculated for the first time. The electronic band structure and electronic energy density of states indicate the strong cova- lent Ir-si and si-si bonding, which leads to the formation of the rigid structure of Li2Irsi3. strong covalency gives rise to a high Debye temperature in this system. We discuss the theoretical results in detail in this paper.

关键词： silicide superconductor crystal structure elastic properties electronic structures

Elastic, thermodynamic, electronic, and optical properties of recently discovered superconducting transition metal boride NbRuB:An ab-initio investigation

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Chinese Physics B 2017年第10期26卷 339-347页

作者： F Parvin s.h.naqib Department of Physics University of Rajshahi

The elastic, thermodynamic, electronic, and optical properties of recently discovered and potentially technologically important transition metal boride NbRuB, are investigated using the density functional formalism. Both generalized gradient approximation （GGA） and local density approximation （LDA） are used for optimizing the geometry and for estimating various elastic moduli and constants. The optical properties of NbRuB are studied for the first time with different photon polarizations. The frequency （energy） dependence of various optical constants complement quite well the essential features of the electronic band structure calculations. Debye temperature of NbRuB is estimated from the thermodynamical study. All these theoretical estimates are compared with published results, where available, and discussed in detail. Both electronic band structure and optical conductivity reveal robust metallic characteristics. The NbRuB possesses significant elastic anisotropy. Electronic features, on the other hand, are almost isotropic in nature. The effects of electronic band structure and Debye temperature on the emergence of superconductivity are also analyzed.

关键词： hard materials ternary borides DFT calculations electronic band structure optical properties superconductivity

Field-dependent resistive transitions in YBa_2Cu_3O_(7-δ) thin films:Influence of the pseudogap on vortex dynamics

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Chinese Physics B 2015年第1期24卷 467-473页

作者： s.h.naqib R s Islam Department of Physics University of RajshahiRajshahi-6205 Bangladesh

The nature of resistive transition of high-quality crystalline thin films of YBa2Cu3O7-δhas been studied under magnetic fields（h） applied along the c direction over a wide range of doped holes, p, in the Cu O2 planes. The field- and temperature-dependent in-plane resistivity, ρab（T, h）, has been analyzed within the thermally assisted flux-flow（TAFF）formalism. The flux activation energy, U（T, h）, has been extracted from this analysis. The low-T part of the ρab（T, h）data can be described by an activation energy having the functional form of U（T, h） =（1- t）m（h-0/h）β, where t = T /Tc（reduced temperature）, and h0 is a field scale that primarily determines the magnitude of U（T, h）. The temperature exponent, m, shows a systematic variation with p, whereas the field exponent, β, is insensitive to the p values and is close to unity. The h0, on the other hand, changes rapidly as p is varied. U（T, h） is linked to the pinning potential and consequently on the superconducting condensation energy. since the normal state pseudogap directly affects superconducting condensation energy, a clear correspondence between h0 and the PG energy scale, ε g, is found. Possible implications of these results are discussed.

关键词： Y123 superconductors thermally assisted flux-flow model activation energy pseudogap

New ternary superconducting compound LaRu2As2： Physical properties from density functional theory calculations

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Chinese Physics B 2017年第3期26卷 453-460页

作者： M A hadi M s Ali s.h.naqib A K M A Islam Department of Physics University of Rajshahi Rajshahi 6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International Islamic University Chittagong Chittagong 4203 Bangladesh

In this paper, we perform the density functional theory （DFT） -based calculations by the first-principles pseudopo- tential method to investigate the physical properties of the newly discovered superconductor LaRu2As2 for the first time. The optimized structural parameters are in good agreement with the experimental results. The calculated independent elas- tic constants ensure the mechanical stability of the compound. The calculated Cauchy pressure, Pugh＇s ratio as well as Poisson＇s ratio indicate that LaRu2As2 should behave as a ductile material. Due to low Debye temperature, LaRu2As2 may be used as a thermal barrier coating （TBC） material. The new compound should exhibit metallic nature as its valence bands overlap considerably with the conduction bands. LaRu2As2 is expected to be a soft material and easily machinable because of its low hardness value of 6.8 GPa. The multi-band nature is observed in the calculated Fermi surface. A highly anisotropic combination of ionic, covalent and metallic interactions is expected to be in accordance with charge density calculation.

关键词： new superconductor LaRu2As2 density functional theory (DFT) calculations mechanical proper-ties electronic features

An ab initio investigation of vibrational, thermodynamic, and optical properties of sc_2AlC MAX compound

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Chinese Physics B 2016年第10期25卷 103-108页

作者： M A Ali M T Nasir M R Khatun A K M A Islam s.h.naqib Department of Physics Chittagong University of Engineering and Technology Department of Arts & sciences Bangladesh Army University of Science and Technology Department of Physics University of Rajshahi International Islamic University Chittagong

The structural vibrational, thermodynamical, and optical properties of potentially technologically important, weakly coupled MAX compound, sc2 Al C are calculated using density functional theory(DFT). The structural properties of scAlC are compared with the results reported earlier. The vibrational, thermodynamical, and optical properties are theoretically estimated for the first time. The phonon dispersion curve is calculated and the dynamical stability of this compound is investigated. The optical and acoustic modes are observed clearly. We calculate the helmholtz free energy(F), internal energy(E), entropy(s), and specific heat capacity(Cv) from the phonon density of states. Various optical parameters are also calculated. The reflectance spectrum shows that this compound has the potential to be used as an efficient solar reflector.

关键词： MAX compound phonon dispersion thermodynamical properties optical properties

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI h.GhANDVAR E.JUMAEV s.KhATIR T.CUONG-LE school of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and science Center for Engineering Application and Technology solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Revisiting cerebral endothelial cells in Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

Deciphering the mechanobiology of microglia in traumatic brain injury with advanced microsystems

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Neural Regeneration Research 2025年第8期20卷 2304-2306页

作者： Anthony Procès sylvain Gabriele Univ.Grenoble Alpes InsermU1216Grenoble Institut des NeurosciencesGrenobleFrance Mechanobiology&Biomaterials Group CIRMAPResearch Institute for BiosciencesUniversity of MonsMonsBelgium

Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results from a mechanical insult to the brain,leading to neuronal and axonal damage and subsequently causing a secondary *** minutes ... 详细信息

关键词： traumatic injury damage