检索结果-南通市图书馆

Transport Properties of Bi_2s_3 single Crystals

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 2008年第5期24卷 757-760页

作者： H.T.shaban M.M.Nassary M.s.El-sadek Physics Department Faculty of ScienceSouth Valley Univ.QenaEgypt.

Bi2s3 single crystals were grown by using a modification of Bridgman method. Measurements of the electrical conductivity, Hall effect and thermoelectric power （TEP） were preformed in two crystallographic directions （parallel and perpendicular to the c-axis）. The measurements showed that the electrical conductivity, Hall mobility, and seebeck coefficient have anisotropic nature. From these measurements some physical parameters were estimated and the crystals showed n-type of conduction mechanism. Also, values of the energy gap were found to be different in the two directions.

关键词： Bi2s3 Hall effect Thermoelectric power Electrical conductivity

Revisiting cerebral endothelial cells in Alzheimer’s disease

在线全文

学校读者我要写书评

暂无评论

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

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Complementary roles of glial cells in generating region-specific neuroinflammatory responses and phagocytosis in Parkinson’s disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第10期20卷 2917-2918页

作者： Leyre Ayerra Maria s.Aymerich Universidad de Navarra Facultad de CienciasDepartamento de Bioquímica y GenéticaPamplonaSpain CIMA-Universidad de Navarra PamplonaSpain IdisNA Instituto de Investigación Sanitaria de NavarraPamplonaSpain

Neuroinflammation is associated with Parkinson’s disease:Reactive gliosis and neuroinflammation are hallmarks of Parkinson’s disease(PD),a multisystem neurodegenerative disorder characterized by a progressive loss of dopaminergic *** has long been considered a mere consequence of neuronal loss,but whether it promotes PD or is a key player in disease progression remains to be *** leukocyte antigen.

关键词： inflammation leukocyte generating

strain hardening behavior, strain rate sensitivity and hot deformation maps of AIsI 321 austenitic stainless steel

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第11期28卷 1799-1810页

作者： Mehdi shaban Ghazani Beitallah Eghbali Department of Materials science Engineering University of BonabBonab***Iran Faculty of Materials Engineering Sahand University of TechnologyTabriz51335-1996Iran

Hot compression tests were performed on AIsI 321 austenitic stainless steel in the deformation temperature range of 800–1200℃ and constant strain rates of 0.001,0.01,0.1,and 1 s^(−1).Hot flow curves were used to determine the strain hardening exponent and the strain rate sensitivity exponent,and to construct the processing *** of the strain hardening exponent with strain were used to predict the microstructural evolutions during the hot *** variations were distinguished reflecting the different microstructural *** on the analysis of the strain hardening exponent versus strain curves,the microstructural evolutions were dynamic recovery,single and multiple peak dynamic recrystallization,and interactions between dynamic recrystallization and *** strain rate sensitivity variations at an applied strain of 0.8 and strain rate of 0.1 s^(−1) were compared with the microstructural *** results demonstrate the existence of a reliable correlation between the strain rate sensitivity values and evolved ***,the power dissipation map at the applied strain of 0.8 was compared with the resultant microstructures at predetermined deformation *** microstructural evolutions strongly correlated to the power dissipation ratio,and dynamic recrystallization occurred completely at lower power dissipation ratios.

关键词： strain hardening strain rate sensitivity processing map AIsI 321 austenitic stainless steel hot compression

Warm Deformation Microstructure of a Plain Carbon steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and steel Research International 2011年第7期18卷 41-46页

作者： B Eghbali M shaban Department of Materials Engineering Sahand University of Technology

Grain refinement in a plain carbon steel under intercritical warm deformation was studied by torsion tes ring. Based on the experimental results, the warm flow behaviour and microstructural evolution of ferrite were researched with particular emphasis on the effect of the strain rate in controlling the grain refinement mechanism of fer- rite. The deformed microstructures were investigated at various strain rates using optical microscopy and electron back-scattered diffraction （EBsD）. The EBsD observations indicate that an increase in the strain rate leads to the development of new fine ferrite grains with high angle boundaries. Furthermore, it shows that the annihilation of dislo- cations occurs more readily at lower strain rate. The elongated ferrite grains continuously dynamically recrystallize to form the equiaxed fine ferrite grains. Thereby, the aspect ratio of elongated grains decreases with increasing the strain rate. Furthermore, the peak stress and steady state stress of ferrite both increase with increasing strain rate. Based on the study, the effect of strain rate on the development of fine ferrite grains during continuous dynamic recrystallization of ferrite was analyzed in detail.

关键词： grain refinement steel strain rate torsion testing EBsD

Bending analysis of five-layer curved functionally graded sandwich panel in magnetic field:closed-form solution

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2021年第2期42卷 251-274页

作者： M.shaban H.MAZAHERI Mechanical Engineering Department Bu-Ali Sina UniversityHamadan 3869-6517Iran

In this paper,an exact closed-form solution for a curved sandwich panel with two piezoelectric layers as actuator and sensor that are inserted in the top and bottom facings is *** core is made from functionally graded(FG)material that has heterogeneous power-law distribution through the radial *** is assumed that the core is subjected to a magnetic field whereas the core is covered by two insulated composite *** determine the exact solution,first characteristic equations are derived for different material types in a polar coordinate system,namely,magneto-elastic,elastic,and electro-elastic for the FG,orthotropic,and piezoelectric materials,*** displacement-based method is used instead of the stress-based method to derive a set of closed-form real-valued solutions for both real and complex *** on the elasticity theory,exact solutions for the governing equations are determined layer-by-layer that are considerably more accurate than typical simplified *** accuracy of the presented method is compared and validated with the available literature and the finite element *** effects of geometrical and material parameters such as FG index,angular span along with external conditions such as magnetic field,mechanical pressure,and electrical difference are investigated in detail through numerical examples.

关键词： five-layer sandwich panel piezoelectric material closed-form solution functionally graded(FG)material magnetic field

Warm Deformation of Low Carbon steel Using Forward Extrusion-Equal Channel Angular Pressing Technique

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and steel Research International 2013年第2期20卷 68-71页

作者： B Eghbali M shaban Department of Materials science Engineering Sahand University of Technology

A combination of extrusion and equal channel angular pressing （ECAP） was used to deform a plain low carbon steel. This process consists of two successive deformations by extrusion and ECAP in a single die （Ex-ECAP）. Cylindrical samples were heated to predefined temperatures （650 and 850 ℃） and then pressed through a die channel with crosshead speed of 10 mm/s. Microstructure and resultant mechanical properties of processed material were studied. The results showed that pressing temperature has a significant effect on the resultant microstructure. While at 650 ℃, the cold worked structure with elongated ferrite grains were obtained, and at 850 ℃ the microstructure consisted of elongated ferrite grains and very fine grains at their boundaries as a consequence of continuous dynamic recrystallization （CDRX） of ferrite phase. Also at 850 ℃, a particular microstructure consisted of cold worked ferrite and static recrystallized grains on shear bands was obtained.

关键词： extrusion equal channel angular pressing low carbon steel

Characterization of Austenite Dynamic Recrystallization under Different Z Parameters in a Microalloyed steel

在线全文

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 2011年第4期27卷 359-363页

作者： M.shaban B.Eghbali Department of Materials science and Engineering Sahand University of Technology

A low carbon Nb-Ti microalloyed steel was subjected to hot torsion testing over the temperature range 850-1100℃ and strain rates 0.01-1 s-1 to study the influence of deformation conditions on the dynamic recrystallization characteristics of austenite. The results show that dynamic recrystallization occurs more easily with the decrease of strain rate and the increase of deformation temperature. The complete dynamically recrystallized grain size as a function of Zener-Hollomon parameter was established. It was found that dynamically recrystallized grain sizes decrease with increasing strain rate and decreasing deformation temperature. The effect of microalloying elements on peak strain was investigated and the solute drag corrected peak strain was determined. Also, the dynamic recrystallization map of austenite was obtained by using recrystallization critical parameters.

关键词： Dynamic recrystallization Microalloyed steel Grain size Hot torsion