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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN M.MOHAMMADIMEHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

Electrical Properties of Li-doped P-type ZnO Ceramics

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Journal of Materials Science & Technology 2009年第3期25卷 314-318页

作者： A.H. Salama f.f. Hammad Physical Chemistry Department National Research Center Inorganic Chemistry Department National Research Center

Li-doped p-type ZnO ceramics were prepared by conventional methods according to the chemical formula Zn1-xLixO2 where x=0.5, 1.0, 1.5 and 2.0 mole fraction, respectively. The crystal structures of the prepared samples were studied by X-ray diffraction analysis. The dielectric properties （including dielectric constant ε′ and dielectric loss ε″） and dc-electrical conductivity [σ（Ω^-***^-1）] were investigated. The dielectric constant ε′ was sharply decreased at the low frequency range and independent on frequency at high frequency range. Otherwise, the dielectric loss ε″ varied with frequency and showed absorption peak located from 200 Hz to 4 kHz and moved to higher frequency as the concentration of Li＋ doped increased. It was found that dcelectrical conductivity logσ varied from -9 to -5 and the energy gap width were calculated by using Arrhenius equation. The p-type conductivity of Li-doped ZnO may be attributed to the formation of a Lizn-Lii donor complex, which is limited by reducing the amount of Lii.

关键词： P-type ZnO ceramics Dielectric constant Dielectric loss dc-conductivity

An old issue and a new challenge for nuclear reactor safety

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frontiers in Energy 2021年第4期15卷 854-859页

作者： f.D’AURIA University of Pisa DESTEC/GRNSPG–L.go L.Lazzarino 256100 PisaItaly

Nuclear reactor safety(NRS)and the branch accident analysis(AA)constitute proven technologies:these are based on,among the other things,long lasting research and operational experience in the area of water cooled nuclear reactors(WCNR).Large break loss of coolant accident(LBLOCA)has been,so far,the orienting scenario within AA and a basis for the design of *** incomplete vision for those technologies during the last few years is as follows:Progress in fundamentals was stagnant,namely in those countries where the WCNR were *** became evident,noticeably in relation to nuclear fuel under high *** estimate plus uncertainty(BEPU)techniques were perfected and available for *** and informatics systems were in extensive use and their impact in case of accident becomes more and more un-checked(however,quite irrelevant in case of LBLOCA).The time delay between technological discoveries and applications was becoming *** present paper deals with the LBLOCA that is inserted into the above *** conclusion is that regulations need suitable modification,rather than lowering the importance and the role of ***,strengths of emergency core cooling system(ECCS)and containment need a tight link.

关键词： large break loss of coolant accident(LBLOCA) nuclear reactor safety(NRS) licensing perspectives basis for design of water cooled nuclear reactors(WCNR)

Axial magnetic field effect in numerical analysis of high power Cherenkov free electron laser

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Chinese Physics B 2019年第6期28卷 176-183页

作者： f BazoubAND B Maraghechi Department of Physics Fasa UniversityPost code 74616-86131FasaIran Department of Physics Manhattanville CollegePurchaseNew York 10577USA

Cherenkov free electron laser(CfEL) is simulated numerically by using the single particle method to optimize the electron beam. The electron beam is assumed to be moving near the surface of a flat dielectric slab along a growing radiation. The set of coupled nonlinear differential equations of motion is solved to study the electron dynamics. for three sets of parameters, in high power CfEL, it is found that an axial magnetic field is always necessary to keep the electron beam in the interaction region and its optimal strength is reported for each case. At the injection point, the electron beam’s distance above the dielectric surface is kept at a minimum value so that the electrons neither hit the dielectric nor move away from it to the weaker radiation fields and out of the interaction region. The optimal electron beam radius and current are thereby calculated. This analysis is in agreement with two previous numerical studies for a cylindrical waveguide but is at odds with analytical treatments of a flat dielectric that does not use an axial magnetic field. This is backed by an interesting physical reasoning.

关键词： Cherenkov free electron laser axial magnetic field flat dielectric slab electron beam

Pancreatic metastasis from mycosis fungoides mimicking primary pancreatic tumor

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World Journal of Gastroenterology 2016年第12期22卷 3496-3501页

作者： Paola Ceriolo Valentina fausti Elisa Cinotti Silvia Bonadio Lizzia Raffaghello Giovanna bianchi Giulio fraternali Orcioni Roberto fiocca franco Rongioletti Vito Pistoia Giacomo Borgonovo Course in Paediatric Science Fetal-Perinatal and Paediatric Pathology University of Genoa Pathology Unit Istituto Giannina Gaslini Section of Dermatology IRCCS AOU San Martino-IST Pathology Unit IRCCS AOU San Martino-IST Laboratory of Oncology Istituto Giannina Gaslini Pathology Unit IRCCS AOU San Martino-IST and University of Genoa Surgery Unit IRCCS AOU San Martino-IST and University of Genoa

Mycosis fungoides(Mf) is a cutaneous T-cell lymphoma that can undergo local progression with possible systemic dissemination. We report a case of a patient affected by Mf with a pancreatic mass that was a diagnostic challenge between primitive tumor and pancreatic metastasis from Mf. Clinical setting findings and imaging studies raised the suspicion of a pancreatic primary neoplasm. A diagnostic clue was provided by the combined histomorphologic/immunohistochemical study of pancreatic and cutaneous biopsies, which revealed a pancreatic localization of Mf. Considering the rarity of metastatic localization of Mf to the pancreas, we next investigated whether chemokinechemokine receptor interactions could be involved in the phenomenon to provide new insight into the possible mechanisms underlying metastatic localization of Mf to the pancreas. Histological analyses of archival pancreatic tissue demonstrated that glucagon-secreting cells of the pancreatic islets expressed the CCL27 chemokine, which may have attracted in our case metastatic Mf cells expressing the complementary receptor CCR10.

关键词： Differential diagnosis Pancreatic mass Extracutaneous localization Mycosis fungoides CCL27 CCR10

Intranasal nerve growth factor bypasses the blood-brain barrier and affects spinal cord neurons in spinal cord injury

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Neural Regeneration Research 2014年第10期9卷 1025-1030页

作者： Luigi Aloe Patrizia bianchi Alberto De Bellis Marzia Soligo Maria Luisa Rocco Cellular Biology and Neurobiology Institute National Research Council(CNR) Maria Rosaria Maglione foundation Onlus NapoliItaly Intitute of Translational Pharmacology National Research Council(CNR)

The purpose of this work was to investigate whether, by intranasal administration, the nerve growth factor bypasses the blood-brain barrier and turns over the spinal cord neurons and if such therapeutic approach could be of value in the treatment of spinal cord injury. Adult Sprague-Dawley rats with intact and injured spinal cord received daily intranasal nerve growth factor administration in both nostrils for 1 day or for 3 consecutive weeks. We found an in-creased content of nerve growth factor and enhanced expression of nerve growth factor receptor in the spinal cord 24 hours after a single intranasal administration of nerve growth factor in healthy rats, while daily treatment for 3 weeks in a model of spinal cord injury improved the deifcits in locomotor behaviour and increased spinal content of both nerve growth factor and nerve growth factor receptors. These outcomes suggest that the intranasal nerve growth factor bypasses blood-brain barrier and affects spinal cord neurons in spinal cord injury. They also suggest exploiting the possible therapeutic role of intranasally delivered nerve growth factor for the neuroprotection of damaged spinal nerve cells.

关键词： nerve regeneration spinal cord injury nerve growth factor intranasal delivery blood-brain barrier motor function leptin neuroprotection rats neural regeneration

Characterization of Phases in an As-cast Copper-Manganese-Aluminum Alloy

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Journal of Materials Science & Technology 2006年第6期22卷 779-784页

作者： J.Iqbal f.Hasan f.Ahmad Department of Metallurgical and Materials Engineering University of Engineering and TechnologyLahorePakistan

Copper-manganese-aluminum （CMA） alloys, containing small additions of fe, Ni, and Si, exhibit good strength and remarkable corrosion resistance against sea water. The alloys are used in as-cast condition, and their microstructure can show wide variations. The morphology, crystallography and composition of the phases presented in an as-cast （CMA） alloy of nominal composition Cu-14%Mn-8%Al-3%fe-2%Ni were investigated using optical, electron optical, and microprobe analytical techniques. The as-cast microstructure consisted of the grains of fcc α and bcc β-phases alongwith intermetallic precipitates of various morphologies. The room temperature microstructure exhibited four different types of precipitates inside the α-grains： the ＇large＇ dendritic-shaped particles and the cuboid-shaped precipitates, which were rich in fe and Mn and had an fcc structure, while the ＇small＇ dendritic-shaped particles and the globular precipitates were based on feaAI and had DO3 structure. These four different morphologies of intermetallic precipitates exhibited discrete orientation-relationships with the α-matrix. The β-grains only contained very small cuboid shaped precipitates, which could only be resolved through transmission electron microscopy. These precipitates were found to be based on fe3Al and had the DO3 structure.

关键词： Orientation relationship DO3 structure Intermetallic phases

Numerical simulation of wave transformation,breaking and runup by a contravariant fully non-linear Boussinesq equations model

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Journal of Hydrodynamics 2016年第3期28卷 379-388页

作者： f.GALLERANO G.CANNATA f.LASAPONARA Department of Civil Constructional and Environmental Engineering Sapienza University of Rome

In this paper we propose a new model based on a contravariant integral form of the fully non-linear Boussinesq equations （fNBE） in order to simulate wave transformation phenomena, wave breaking, runup and nearshore currents in computational domains representing the complex morphology of real coastal regions. The above-mentioned contravariant integral form, in which Christoffel symbols are absent, is characterized by the fact that the continuity equation does not include any dispersive term. The Boussinesq equation system is numerically solved by a hybrid finite volume-f＇mite difference scheme. A high-order upwind weighted essentially non-oscillatory （WENO） finite volume scheme that involves an exact Riemann solver is implemented. The wave breaking is represented by discontinuities of the weak solution of the integral form of the non-linear shallow water equations （NSWE）. On the basis of the shock-capturing high order WENO scheme a new procedure, for the computation of the structure of the solution of a Riemann problem associated with a wet/dry front, is proposed in order to simulate the run up hydrodynamics in swash zone. The capacity of the proposed model to correctly represent wave propagation, wave breaking, run up and wave induced currents is verified against test cases present in literature. The results obtained are compared with experimental measures, analytical solutions or alternative numerical solutions. The proposed model is applied to a real case regarding the simulation of wave fields and nearshore currents in the coastal region opposite San Mauro Cilento （Italy）.

关键词： fully non-linear Boussinesq equations contravariant formulation Christoffel symbols upwind WENO scheme wet-dryfronts

Inflammation, lipid metabolism and cardiovascular risk in rheumatoid arthritis: A qualitative relationship?

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World Journal of Orthopedics 2014年第3期5卷 304-311页

作者： Carmen García-Gómez Maria bianchi Diana de la fuente Lina Badimon Teresa Padró Emili Corbella Xavier Pintó Department of Rheumatology Consorci Sanitari de Terrassa (CST)Unitat Investigació Biomèdica CST-UAB (Universitat Autònoma de Barcelona)08227-TerrassaBarcelonaSpain Department of Rheumatology Hospital de Viladecans08840-ViladecansBarcelonaSpain Cardiovascular Research Center CSIC-ICCCBiomedical Research Institute Sant-Pau08025-BarcelonaSpain Lipid and Vascular Risk Unit Department of Internal MedicineHospital Universitari de Bellvitge-IDIBELLL’Hospitalet de LlobregatBarcelona University08907 FipecCIBERobn ISCIIISpain

Life expectancy in patients with rheumatoid arthritis(RA)is reduced compared to the general population owing to an increase in cardiovascular diseases(CVD)not fully explained by traditional cardiovascular risk *** recent years,interest has been focused on the alterations in lipid metabolism in relation to chronic inflammation as one of the possible mechanisms involvedin the pathogenesis of atherosclerosis of RA *** regarding this issue has revealed quantitative alterations in lipoproteins during the acute-phase reaction,and has also demonstrated structural alterations in these lipoproteins which affect their functional *** many alterations in lipid metabolism have been described in this regard,these structural changes associated with inflammation are particularly important in high-density lipoproteins as they affect their cardioprotective *** this respect,excessive oxidation in low-density lipoprotein(LDL)and increased lipoprotein(a)with a predominance of smaller apolipoprotein(a)isoforms has also been *** article will discuss proinflammatory high-density lipoproteins(pi HDL),oxidized LDL and lipoprotein(a).Elevated concentrations of these lipoproteins with marked pro-atherogenic properties have been observed in RA patients,which could help to explain the increased cardiovascular risk of these patients.

关键词： Rheumatoid arthritis Cardiovascular disease Lipoproteins Proinflammatory high-density lipoproteins Lipoprotein(a) Oxidized low-density lipoproteins Lipid metabolism Inflammation