检索结果-南通市图书馆

Effects of Multiple strengthening Treatments on Mechanical Properties and stability of Nanoscale Precipitated Phases in an Aluminum-Copper-Lithium Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 2010年第12期26卷 1078-1082页

作者： s.ahmadi H.Arabi A.shokuhfar Department of Material science Faculty of EngineeringTarbiat Modares UniversityTehranIran Center of Excellence of Advanced Materials and Processing(CEAMP) Department of Metallurgy and Materials Science and EngineeringIran University of Science & Technology(IUST)NarmakTehranIran Department of Material science Faculty of Mechanical EngineeringK.N.Toosi University of TechnologyTehranIran

Effects of multiple strengthening treatments （i.e. ag mechanical properties and stability of nanoscale prec in this research. Various tests such as hardness, tensi ng either at three or four consecutive temperatures） on pitated phases in an AA2090 alloy have been evaluated e, electrical resistance, differential scanning calorimetric （DsC）, and transmission electron microscopy （TEM） have been performed. The results show that the ultimate tensile strength （UTs） and the yield strength of the samples aged at four consecutive temperatures （i.e. natural aging＋190℃＋150℃＋100℃） can be increased approximately to 660 and 610 MPa, respectively. It is also found that precipitation of T1 phase occurs during multiple aging process of the alloy and the higher amounts of enthalpies shown in DsC charts are linked to higher volume fraction of this precipitate. Furthermore, TEM observations reveal that T1 phase has plate shape morphology and its crystal structure is in the form of hcp with lattice parameters of a=0.467 nm and c=0.878 nm.

关键词： Multiple strengthening Thermo mechanical treatment (TMT) selected area electron diffraction (sAED) pattern Inter planar spacing (d)

Evaluation of the Electroslag Remelting Process in Medical Grade of 316LC stainless steel

在线全文

学校读者我要写书评

暂无评论

Journal of Materials science & Technology 2009年第5期25卷 592-596页

作者： s.ahmadi H.Arabi A.shokuhfar A.Rezaei Institute of Advanced Technologies for Metallic Materials Tarbiat Modares University Center of Excellence of Advanced Materials and Processing(CEAMP) Department of Metallurgy and Materials Science and EngineeringIran University of Science&Technology(IUST) Department of Material science Faculty of Mechanical EngineeringK.N.Toosi University of Technology

This study is focused on the effects of electroslag remelting by prefused slag （CaO, Al2O3, and CaF2） on macrostructure and reduction of inclusions in the medical grade of 316LC （316LVM） stainless steel. Analysis of the obtained results indicated that for production of a uniform ingot structure during electroslag remelting, shape and depth of the molten pool should be carefully controlled. High melting rates led to deeper pool depth and interior radial solidification characteristics, while decrease in the melting rates caused more reduction of nonmetallic inclusions. Large shrinkage cavities formed during the conventional casting process in the primary ingots were found to be the cause of the fluctuation in the melting rate, pool depth and extension of equiaxed crystals zone.

关键词： Ultra clean steel Electroslag Radial solidification remelting Prefused slag Vertical solidification

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

Cohomogeneity One de sitter space s1 n

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica sinica,English series 2010年第10期26卷 1915-1926页

作者： P.ahmadi s.M.B.KAsHANI H.ABEDI Department of Pure Mathematics Faculty of Mathematical SciencesTarbiat Modares University Group of Mathematics School of Sciences Bu-Ali Sina University

In this paper we study the cohomogeneity one de sitter space s1 n. We consider the actions in both proper and non-proper cases. In the first case we characterize the acting groups and orbits and we prove that the orbit space is homeomorphic to R. In the latter case we determine the groups and consequently the orbits in some different cases and prove that the orbit space is not Hausdorff.

关键词： Cohomogeneity one Lorentzian space de sitter space

L^q Inequalities and Operator Preserving Inequalities

在线全文

学校读者我要写书评

暂无评论

Analysis in Theory and Applications 2014年第4期30卷 377-386页

作者： M.Bidkham s.ahmadi Department of Mathematics Semnan University

Let Pn be the class of polynomials of degree at most n. Rather and shah [15] proved that if P∈Pn and P（z） 6=0 in｜z｜〈1, then for every R〉0 and 0≤q〈∞,｜B[P（Rz）]｜q≤｜RnB[zn]＋λ0｜q｜1＋zn｜q ｜P（z）｜q, where B is a Bn-operator. In this paper, we prove some generalization of this result which in particular yield-s some known polynomial inequalities as special. We also consider an operator Dαwhich maps a polynomial P（z） into DαP（z）：=nP（z）＋（α-z）P′（z） and obtain exten-sions and generalizations of a number of well-known Lq inequalities.

关键词： Complex polynomial polar derivative B-operator.

Effect of Gaussian size distribution width on minimum fluidization velocity in tapered gas–solid fluidized beds

在线全文

学校读者我要写书评

暂无评论

Particuology 2022年第7期20卷 71-84页

作者： Mojtaba Rasteh Goodarz ahmadi s.H.Hosseini Department of Chemical Engineering Hamedan University of TechnologyHamedanP.O.Box 65155-579Iran Department of Mechanical and Aeronautical Engineering Clarkson UniversityPotsdamNY 13699-5725USA Department of Chemical Engineering Ilam UniversityIlam 69315-516Iran

This paper investigated the effect of Gaussian distribution width,average particle diameter,particle loading,and the tapered angle on minimum fluidization velocity(U_(mf))by conducting extensive experiments in tapered fluidized *** powders with Gaussian size distribution and different distribution widths were used in the *** increase in U_(mf)with increasing the average particle diameter,particle loading,and the tapered angle was *** was also a nonmonotonic behavior of Umf as the Gaussian distribution width *** empirical correlation including dimensionless groups for predicting Umf in tapered beds was developed in which the effect of distribution width was *** proposed correlation predictions were in good agreement with the experimental data,with a maximum deviation of 16.5%and average and standard deviations of,respectively,6.4%and 7.4%.The proposed correlation was also compared with three earlier models,and their accuracy was discussed.

关键词： Tapered fluidized bed Minimum fluidization velocity Gaussian size distribution Distribution width Dimensional analysis

A systematic review of progenitor survival and maturation in Parkinsonian models

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

Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience Center University of GalwayGalwayIreland

stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged froms transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant