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DIScREPANcIES IN THE REGRESSION mODELLING OF REcRYSTALLIZATION RATE AS USING THE DATA FROm PHYSIcAL SImULATION TESTS

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Acta metallurgica Sinica(English Letters) 2004年第3期17卷 221-228页

作者： L.P.Karjalainen m.c.somani S.F.medina Department of mechanical Engineering University of OuluFIN-90014 OuluFinlandDepartment of Mechanical EngineeringUniversity of OuluFIN-90014 OuluFinlandCentro Nacional de Investigaciones Metallurgicas(CENIM-CSIC) ES-28040 madrid Spain

The analysis of numerous experimental equations published in the literature reveals awide scatter in the predictions for the static recrystallization kinetics of steels. Thepowers of the deformation variables, strain and strain rate, similarly as the powerof the grain size vary in these equations. These differences are highlighted and thetypical values are compared between torsion and compression tests. Potential errorsin physical simulation testing are discussed.

关键词： physical simulation static recrystallization regression modeling hot working steel

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Observations on the Formation of Ultrafine Ferrite Grain Size in Steels by Physical Simulation Routes

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Observations on the Formation of Ultrafine Ferrite Grain Siz...

Improving the mechanical Properties of copper Alloys by Thermo-mechanical Processing

The Fourth International conference on Physical and Numerical Simulation of materials Processing (IcPNS’2004)

作者： L.P.Karjalainen m.c.somani University of Oulu Department of mechanical Engineering P.O.Box 4200 FIN-90014 Oulu FINLAND University of Oulu Department of mechanical Engineering P.O.Box 4200 FIN-90014 Oulu FINLAND

Some observations are reported on the simulation of two thermo-mechanical routes to produce ultra-fine ferrite grain size in steels. One c-mn grade and Nb, Nb-Ti and Nb-high Ti bearing steels were used in the tests performed on a Gleeble simulator and a laboratory rolling mill. The routes included severe hot deformation of prior grain-refined austenite at the temperatures close to Ar3 (DIF) and static recrystallization of fine-grained cold-rolled martensite (SRm). It was observed that the hot deformation induces the formation of ferrite above the Ar3 temperature of the steel, but severe reductions are required for the complete transformation. Strain of 1.2 can result in about 70% of ferrite with the grain size of about 1.4 - 2 urn in all the studied steels. Similarly, in short annealing of cold-worked martensite, the static recrystallization can also lead to a grain size of about 1.5 μm. The distribution of carbon varies in the microstructures. carbon being in the second phase in the DIF route and in carbide particles in the SRm route, which may have a significant influence on the mechanical properties and the thermal stability of ultrafine grain structure.

关键词： Ultrafine grain size Steels Physical simulation Strain-induced ferrite cold rolling and annealing

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Improving the Mechanical Properties of Copper Alloys by Ther...

Observations on the Formation of Ultrafine Ferrite Grain Size in Steels by Physical Simulation Routes

The Fourth International conference on Physical and Numerical Simulation of materials Processing (IcPNS’2004)

作者： m.c.somani L.P.Karjalainen University of Oulu Department of mechanical Engineering 4KOmT P.O. Box 4200 90014 Oulu FINLAND University of Oulu Department of mechanical Engineering 4KOmT P.O. Box 4200 90014 Oulu FINLAND

Systematic physical simulation of thermo-mechanical processing routes has been applied on a Gleeble 1500 simulator to four copper alloys (wt-%) cu-0.57co-0.32Si, cu-0.55cr-0.065P/cu-0.22Zr-0.035Si and cu-l.01Ni-0.43Si aimed at clarifying the influences of processing conditions on their final properties, strength and electrical conductivity. Flow curves were determined over wide temperature and strain rate ranges. Hardness was used as a measure of the strength level achieved. High hardness was obtained as using equal amounts (strains 0.5) of cold deformation before and after the precipitation annealing stage. The maximum values achieved for the cu-co-Si, cu-cr-P, cu-Zr-Si and cu-Ni-Si alloys were 190, 165, 178 and 193 HV5, respectively. A thermo-mechanical schedule involving the hot deformation-ageing-cold deformation stages showed even better results for the cu-Zr-Si alloy. consequently, the processing routes were designed based on simulation test results and wires of 5 and 2 mm in diameters, have been successfully processed in the industrial scale.

关键词： copper alloys Thermo-mechanical processing Ageing Strength Flow stress Hardness

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Journal of materials Science & Technology 2003年第z1期19卷 112-114页

作者： L.X. Pan L.P. Karjalainen m. c. somani University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland University of Oulu Department of Mechanical Engineering P.O. Box 4200 FIN-90014 Oulu Finland

Some observations are reported on the simulation of two thermomechanical routes to produce ultrafine ferrite grainsize in steels. One c-mn grade and Nb, Nb-Ti and Nb-high Ti bearing steels were used in the tests performed ona Gleeble simulator and a laboratory rolling mill. The routes included severe hot deformation of prior grain-refinedaustenite at the temperature close to Ar3 (DIF) and static recrystallization of fine-grained cold-rolled martensite(SRm). It was observed that the hot deformation induces the formation of ferrite above the Ar3 temperature of thesteel, but severe reductions are required for the complete transformation. Strain of 1.2 can result in about 70% offerrite with the grain size of about 1.4～2μm in all the studied steels. Similarly, in short annealing of cold-workedmartensite, the static recrystallization can also lead to a grain size of about 1.5 μm. The distribution of carbonvaries in the microstructures, carbon being in the second phase in the DIF route and in carbide particles in the SRmroute, which may have a significant influence on the mechanical properties and the thermal stability of ultrafine grainstructure.

关键词： Ultrafine grain size, Steels, Physical simulation, Strain-induced ferrite, cold rolling and annealing

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： md Al Raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

Role of endoscopic ultrasound in idiopathic pancreatitis

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World Journal of Gastroenterology 2017年第38期23卷 6952-6961页

作者： Piyush somani Tagore Sunkara malay Sharma Department of Gastr-oenterology Jaswant Rai Speciality Hospital Department of Gastroenterology and Hepatology The Brooklyn Hospital Center Clinical Affliate of The Mount Sinai Hospital

Recurrent acute pancreatitis(RAP) is defined based on the occurrence of two or more episodes of acute pancreatitis. The initial evaluation fails to detect the cause of RAP in 10%-30% of patients, whose condition is classified as idiopathic RAP(IRAP). Idiopathic acute pancreatitis(IAP) is a diagnostic challenge for gastroenterologists. In view of associated morbidity and mortality, it is important to determine the aetiology of pancreatitis to provide early treatment and prevent recurrence. Endoscopic ultrasound(EUS) is an investigation of choice for imaging of pancreas and biliary tract. In view of high diagnostic accuracy and safety of EUS, a EUS based management strategy appears to be a reasonable approach for evaluation of patients with a single/recurrent idiopathic pancreatitis. The most common diagnoses by EUS in IAP is biliary tract disease. The present review aims to discuss the role of EUS in the clinical management and diagnosis of patients with IAP. It elaborates the diagnostic approach to IAP in relation to EUS and other different modalities. controversial issues in IAP like when to perform EUS, whether to perform after first episode or recurrent episodes, comparison among different investigations and the latest evidence significance are detailed.

关键词： Endoscopic ultrasound Pancreatitis ERcP mRcP USG cT Idiopathic recurrent pancreatitis Ascariasis Pancreatic cancer Biliary sludge Gallstones microlithiasis common bile duct stones

Efficacy of repetitive transcranial magnetic stimulation in treatmentresistant depression:the evidence thus far

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General Psychiatry 2019年第4期32卷 167-174页

作者： Aditya somani Sujita Kumar Kar Department of Psychiatry Mental Health InstituteChandigarhIndia departm ent of Psychiatry King George's Medical UniversityLucknowUttar PradeshIndia

Depression is a common mental disorder, which attributes to significant morbidity, disability and burden of care. A significant number of patients with depression still remain symptomatic after adequate trials of antidepressant treatment as well as psychotherapy, which is often referred to as treatment-resistant depression. Neuromodulation techniques—like electroconvulsive therapy, vagus nerve stimulation, transcranial magnetic stimulation (TmS) and transcranial direct current stimulation, may be useful augmenting techniques in depression, mostly recommended for treatment-resistant cases. Robust evidence exists regarding the efficacy of electroconvulsive therapy in the management of treatment-resistant depression;however, other techniques are understudied. TmS has been increasingly studied in various psychiatric disorders including depression. It has been approved by the US Food and Drug Administration for use in major depressive disorder. Over the past two decades, TmS has been studied in diverse groups of the population with depression using several research designs. This article gives an overview of the efficacy of repetitive TmS in treatment-resistant depression with the recent evidence.

关键词： magnetic stimulation treatmentresistant depression

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EmBASE,Ovid mEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

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