检索结果-南通市图书馆

国外畜牧学（饲料） 1999年第5期 3-4,2页

作者：陈茜 gisele gizzi 博士

二恶英二恶英和二恶英类化合物是一个有400种以上不同分子的族类(75种多氯代二苯并二恶英-PCDD,135种多氯代二苯并呋喃-PCDF和209种多氯代联苯-PCB),其特点是具有共同的化学结构。其中,7种多氯代二苯并二恶英。

关键词：动物饲料二恶英食物链

Intra-cycle depolarization of ultraintense laser pulses focused by off-axis parabolic mirrors

在线全文

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2018年第2期6卷 141-148页

作者： Luca Labate Gianluca Vantaggiato Leonida A.gizzi Istituto Nazionale di Ottica Consiglio Nazionale delle Ricerche Istituto Nazionale di Fisica Nucleare Sezione di Pisa

A study of the structure of the electric and magnetic fields of ultraintense laser pulses focused by an off-axis parabolic mirror is reported. At first, a theoretical model is laid out, whose final equations integration allows the space and time structure of the fields to be retrieved. The model is then employed to investigate the field patterns at different times within the optical cycle, for off-axis parabola parameters normally employed in the context of ultraintense laser–plasma interaction experiments. The results show that nontrivial, complex electromagnetic field patterns are observed at the time at which the electric and magnetic fields are supposed to vanish. The importance of this effect is then studied for different laser polarizations, f numbers and off-axis angles.

关键词： laser-driven particle acceleration laser focusing off-axis parabolic mirrors ultrashort laser pulses

Biomechanical modeling of metal screw loadings on the human vertebra

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2021年第2期37卷 307-320页

作者： Leonardo Molinari Cristina Falcinelli Alessio gizzi Alberto Di Martino Department of Engineering Campus Bio-Medico University of RomeVia A.del Portillo 21Rome 00128Italy Department of Biomedical and Neuromotor Science DIBINEM University of BolognaBolognaItaly 1st Orthopaedic and Traumatologic Clinic IRCCS Istituto Ortopedico RizzoliBolognaItaly

During spinal fusion surgery,angled screw insertion can provide a more favorable stress distribution reducing failure events(screw breakage and loosening).Finite element(FE)analysis can be employed for identifying the optimal insertion path,preventing stress concentrations,and ensuring a lower failure *** this work,a patient-specific FE model of L4 vertebra,virtually implanted with two pedicle screws,was obtained from diagnostic images and numerically *** elastic,inhomogeneous,and isotropic material properties were assigned to bone based on density distributions reconstructed from the medical *** mechanical response of the screws-vertebra system was analyzed through a progressive damage procedure,considering a stress-based *** screws insertion angles were simulated,as well as physiological loading *** each loading case,screw orientation influences the fracture mechanism(i.e.,brittle or ductile one),as well as the fracture pattern and ***,stresses in trabecular bone and pedicle screws are significantly affected by the screw *** caudomedial trajectory indicates the most safe case,significantly reducing the stress concentrations in both trabecular bone and *** findings aim to furnish a useful indication to surgeons regarding the screws insertion angle,further reducing the failure risk and improving the clinical outcome of the fixation procedure.

关键词： Fracture mechanics Patient-specific FE modeling Vertebra mechanics Screw orientation Stress analysis

Theoretical and Numerical Modeling of Nonlinear Electromechanics with applications to Biological Active Media

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Computational Physics 2015年第1期17卷 93-126页

作者： Alessio gizzi Christian Cherubini Simonetta Filippi Anna Pandolfi Nonlinear Physics and Mathematical Modeling Laboratory ***University Campus Bio-Medico of RomeVia A.del Portillo 2100128 RomeItaly International Center for Relativistic Astrophysics Network ***University Campus Bio-Medico of RomeVia A.del Portillo 2100128 RomeItaly Civil and Environmental Engineering Department Politecnico di Milano Piazza Leonardo da Vinci 3220133 MilanoItaly

We present a general theoretical framework for the formulation of the nonlinear electromechanics of polymeric and biological active *** approach developed here is based on the additive decomposition of the Helmholtz free energy in elastic and inelastic parts and on the multiplicative decomposition of the deformation gradient in passive and active *** describe a thermodynamically sound scenario that accounts for geometric and material *** view of numerical applications,we specialize the general approach to a particular material model accounting for the behavior of fiber reinforced ***,we use the model to solve via finite elements a uniaxial electromechanical problem dynamically activated by an electrophysiological *** for nonlinear solid mechanics and computational electrophysiology are finally discussed.

关键词： Active electromechanical media Helmholtz free energy multiplicative decomposition of the deformation gradient active deformation active stress

Modelling Thermo-Electro-Mechanical Effects in Orthotropic Cardiac Tissue

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Computational Physics 2020年第1期27卷 87-115页

作者： Ricardo Ruiz-Baier Alessio gizzi Alessandro Loppini Christian Cherubini Simonetta Filippi Mathematical Institute University of OxfordWoodstock RoadOxford OX26GGUnited Kingdom Laboratory of Mathematical Modelling Institute of Personalised MedicineSechenov UniversityMoscowRussian Federation Nonlinear Physics and Mathematical Modeling Department of EngineeringUniversity Campus Bio-Medico of RomeVia A.del Portillo 2100128RomeItaly International Center for Relativistic Astrophysics(ICRA) and ICRANetPiazza delle Repubblica 10I-65122 PescaraItaly

In this paper we introduce a new mathematical model for the active contraction of cardiac muscle,featuring different thermo-electric and nonlinear conductivity *** passive hyperelastic response of the tissue is described by an orthotropic exponential model,whereas the ionic activity dictates active contraction in-corporated through the concept of orthotropic active *** use a fully incompressible formulation,and the generated strain modifies directly the conductivity mechanisms in the medium through the pull-back *** also investigate the influence of thermo-electric effects in the onset of multiphysics emergent spatiotem-poral dynamics,using nonlinear *** turns out that these ingredients have a key role in reproducing pathological chaotic dynamics such as ventricular fibrillation during inflammatory events,for *** specific structure of the governing equations suggests to cast the problem in mixed-primal form and we write it in terms of Kirchhoff stress,displacements,solid pressure,dimensionless electric potential,activation generation,and ionic *** also advance a new mixed-primal finite element method for its numerical approximation,and we use it to explore the properties of the model and to assess the importance of coupling terms,by means of a few computational experiments in 3D.

关键词： Cardiac electromechanics orthotropic active strain thermo-electric coupling scroll wave propagation numerical simulations

Optical diagnostics for density measurement in high-quality laser-plasma electron accelerators

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2019年第2期7卷 40-50页

作者： Fernando Brandi Leonida Antonio gizzi Intense Laser Irradiation Laboratory(ILIL) Istituto Nazionale di Ottica-Consiglio Nazionale delle Ricerche(INO-CNR)Sede Secondaria di PisaVia Moruzzi156124PisaItaly Istituto Nazionale di Fisica Nucleare(INFN) Sezione di PisaLargo Bruno PontecorvoLargoBruno Pontecorvo356127PisaItaly

Implementation of laser-plasma-based acceleration stages in user-oriented facilities requires the definition and deployment of appropriate diagnostic methodologies to monitor and control the acceleration *** overview is given here of optical diagnostics for density measurement in laser-plasma acceleration stages,with emphasis on wellestablished and easily implemented *** for both neutral gas and free-electron number density are considered,highlighting real-time measurement *** interferometry,in its various configurations,from standard two-arm to more advanced common-path designs,is discussed,along with spectroscopic techniques such as Stark broadening and Raman scattering.A critical analysis of the diagnostics presented is given concerning their implementation in laser-plasma acceleration stages for the production of high-quality GeV electron bunches.

关键词： gas target interferometry laser-plasma laser wake-field acceleration Raman scattering Stark broadening

A Bistable FieldModel of Cancer Dynamics

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2012年第1期11卷 1-18页

作者： C.Cherubini A.gizzi M.Bertolaso V.Tambone S.Filippi Nonlinear Physics and Mathematical Modeling Lab University Campus Bio-MedicoI-00128Via A.del Portillo 21RomeItaly International Center for Relativistic Astrophysics-I.C.R.A. University of Rome“La Sapienza”I-00185 RomeItaly Alberto Sordi Foundation-Research Institute on Aging I-00128 RomeItaly Institute of Philosophy of Scientific and Technological Activity University Campus Bio-MedicoI-00128Via A.del Portillo 21RomeItaly

Cancer spread is a dynamical process occurring not only in time but also in space which,for solid tumors at least,can be modeled quantitatively by reaction and diffusion equations with a bistable behavior:tumor cell colonization happens in a portion of tissue and propagates,but in some cases the process is *** a cancer proliferation/extintion dynamics is obtained in many mathematical models as a limit of complicated interacting biological *** this article we present a very basic model of cancer proliferation adopting the bistable equation for a single tumor cell *** reaction-diffusion theory is numerically and analytically studied and then extended in order to take into account dispersal effects in cancer progression in analogy with ecological models based on the porous medium *** implications of this approach for explanation and prediction of tumor development on the lines of existing studies on brain cancer progression are *** potential role of continuum models in connecting the two predominant interpretative theories about cancer,once formalized in appropriatemathematical terms,is discussed。

关键词： Reaction-diffusion equations cancer modeling finite elements method

Inertial confinement fusion ignition achieved at the National Ignition Facility–an editorial

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2023年第3期11卷 73-75页

作者： C.N.Danson L.A.gizzi Editor-in-Chief High Power Laser Science and EngineeringCambridge University PressCambridgeUK AWE AldermastonReadingUK Centre for Inertial Fusion Studies Blackett LaboratoryImperial College LondonLondonUK Editorial Board Member High Power Laser Science and EngineeringCambridge University PressCambridgeUK Istituto Nazionale di Ottica Consiglio Nazionale delle RicerchePisaItaly

On behalf of all at High Power Laser Science and Engineering we would like to congratulate the team at Lawrence Livermore National Laboratory(LLNL)on demonstrating fusion ignition at the National Ignition *** major scientific achievement was realized on the 5 December 2022 at the LLNL and announced at a press briefing on the 13 December 2022 by the United States Department of Energy’s National Nuclear Security *** was a historic milestone and the culmination of decades of effort.

关键词： inertial confinement fusion fusion ignition inertial fusion energy high power lasers

On Spiral Waves Arising in Natural Systems

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2010年第8期8卷 610-622页

作者： D.Bini C.Cherubini S.Filippi A.gizzi P.E.Ricci Istituto per le Applicazioni del Calcolo“M.Picone” CNR I-00161 RomeItaly International Center for Relativistic Astrophysics-I.C.R.A. University of Rome“La Sapienza”I-00185 RomeItaly Nonlinear Physics and Mathematical Modeling Lab Faculty of EngineeringUniversity Campus Bio-MedicoI-00128 RomeItaly Alberto Sordi Foundation-Research Institute on Aging I-00128 RomeItaly Mathematics Department University of Rome“La Sapienza”I-00185 RomeItaly

Spiral waves appear in many different natural contexts:excitable biological tissues,fungi and amoebae colonies,chemical reactions,growing crystals,fluids and gas eddies as well as in *** the existing theories explain the presence of spirals in terms of nonlinear parabolic equations,it is explored here the fact that selfsustained spiral wave regime is already present in the linear heat operator,in terms of integer Bessel functions of complex *** solutions,even if commonly not discussed in the literature because diverging at spatial infinity,play a central role in the understanding of the universality of spiral *** particular,we have studied how in nonlinear reaction-diffusion models the linear part of the equations determines the wave front appearance while nonlinearities are mandatory to cancel out the blowup of *** spiral wave pattern still requires however at least two cross-reacting species to be physically *** implications of such a results are discussed.

关键词： Reaction-diffusion equations biophysics crystal growth heat transfer

Accurate electron beam phase-space theory for ionization-injection schemes driven by laser pulses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Power Laser Science and Engineering 2022年第2期10卷 64-79页

作者： Paolo Tomassini Francesco Massimo Luca Labate Leonida A.gizzi Intense Laser Irradiation Laboratory INO-CNRPisaItaly ELI-NP MagureleIfovRomania Maison de la Simulation CEAUSR Gif-sur-Yette France 4INFNSect.of PisaPisaltaly

After the introduction of the ionization-injection scheme in laser wake field acceleration and of related high-quality electron beam generation methods,such as two-color and resonant multi-pulse ionization injection(Re MPI),the theory of thermal emittance has been used to predict the beam normalized emittance obtainable with those *** recast and extend such a theory,including both higher order terms in the polynomial laser field expansion and non-polynomial corrections due to the onset of saturation effects on a single ***,a very accurate model for predicting the cycle-averaged distribution of the extracted electrons,including saturation and multi-process events,is proposed and *** show that our theory is very accurate for the selected processes of Kr^(8+→10+) and Ar^(8+→10+),resulting in a maximum error below 1%,even in a deep-saturation *** accurate prediction of the beam phase-space can be implemented,for example,in laser-envelope or hybrid particle-in-cell(PIC)/fiuid codes,to correctly mimic the cycle-averaged momentum distribution without the need for resolving the intra-cycle *** introduce further spatial averaging,obtaining expressions for the whole-beam emittance fitting with simulations in a saturated regime,***,a PIC simulation for a laser wakefield acceleration injector in the Re MPI configuration is discussed.

关键词： field theory ionization high-quality electron beams ionization injection laser wakefield acceleration laser-plasma acceleration resonant multi-pulse ionization injection tunnel ionization two-color ionization ultraintense laser pulses