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Radioisotope production using lasers:From basic science to applications

Matter and Radiation at extremes 2024年第3期9卷 31-44页

作者： M.R.D.Rodrigues A.Bonasera M.Scisciò J.A.Pérez-Hernández M.ehret F.Filippi P.L.Andreoli M.Huault H.Larreur D.Singappuli D.Molloy D.Raffestin M.Alonzo G.G.Rapisarda D.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.McNamee M.La Cognata S.Palmerini T.Carriere M.Cipriani G.di Giorgio G.Cristofari R.De Angelis G.A.P.Cirrone D.Margarone L.Giuffrida D.Batani P.Nicolai K.Batani R.Lera L.Volpe D.Giulietti S.Agarwal M.Krupka S.Singh Fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly eNeA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain Centre Lasers Intenses et Applications(CeLIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 energy Holdings Pty FreshwaterNew South WalesAustralia School of Mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom dipartimento di Fisica e Astronomia“e.Majorana ”Università di CataniaCataniaItaly facoltàdi ingegneria e architettura Universitàdegli Studi di Enna“Kore”EnnaItaly dipartimento di ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly dipartimento di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto Nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly eLI Beamlines Facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic eTSIA Universidad Politécnica de MadridMadridSpain dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academy of Sciences PragueCzech Republic Institute of Plasma Physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few micrometers.Protons with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary targets.Under such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical application.The use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on accelerators.In this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other applications.At the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy production.The experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,Spain.Angular distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium detector.Our results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[Nucl.Instrum.Methods Phys.Res.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

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Assimilation of NDVI data in a land surface-Vegetation model for leaf area index predictions in a tree-grass ecosystem

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International Journal of digital earth 2023年第1期16卷 3810-3837页

作者： Nicola Montaldo Andrea Gaspa Roberto Corona dipartimento di ingegneria civile ambientale e architetturaUniversita di CagliariCagliariItaly

Periodic observations of vegetation index,such as the normalized difference vegetation index(NDVI),can be used for data assimilation in heterogenous ecosystems.Indeed,the new Sentinel 2 Multispectral instrument and Landsat 8 Operational Land Imager sensor data are available at such high temporal and spatial resolutions that can be used to detect the patches of the main vegetation components(grass and trees)of heterogenous ecosystems,and capture their dynamics.We demonstrate the possibility to merge grass and tree NDVI observations and models,to optimally provide robust predictions of grass and tree leaf area index.The proposed assimilation approach assimilates NDVI data through the ensemble Kalman filter(enKF)and dynamically calibrates a key vegetation dynamic model parameter,the maintenance respiration coeffcient(ma).In the presence of large bias of the grass and tree ma base values,only the use of the proposed assimilation approach removes the large bias in the biomass balance,dynamically calibrating maintenance respiration coefficients,and corrects the model.The performance of a land surface-vegetation model was improved by assimilating observations of NDVl.The effective impact of the proposed assimilation approach on the evapotranspiration and CO_(2) uptake predictions in the heterogenous ecosystem is also demonstrated.

关键词： Data assimilation leaf area index heterogenous ecosystem vegetation dynamic model Landsat 8 Sentinel 2

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A semi-empirical model for top-down cracking depth evolution in thick asphalt pavements with open-graded friction courses

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Journal of Traffic and Transportation engineering(english edition) 2022年第2期9卷 244-260页

作者： Francesco Canestrari Lorenzo Paolo Ingrassia Amedeo Virgili dipartimento di ingegneria Civile Edile e Architettura(DICEA)UniversitàPolitecnica delle MarcheAncona 60131Italy

Thick asphalt pavements with open-graded friction course(OGFC) are exposed to topdown cracking(TDC), a distress consisting of longitudinal cracks that initiate on the pavement surface close to the wheel path and propagate downwards. The main objective of this study is to develop a semi-empirical model for the prediction of TDC depth evolution for such pavements. For this purpose, a series of cores were taken from different Italian motorway pavements affected by TDC and analyzed in the laboratory. Cracked cores taken from the wheel path area were analyzed to determine TDC depth, whereas intact cores taken from the middle of the lane(not affected by traffic loadings) were tested to obtain the volumetric and mechanical properties of the OGFC mixture. The proposed model, developed on the basis of the results already available in literature and on the findings of the laboratory investigation, predicts the evolution of TDC depth as a function of the applied traffic loadings(in terms of 12-ton fatigue equivalent single axle loads, i.e., eSALs). The model is sigmoidal with a maximum TDC depth assumed equal to 150 mm. The shape parameter of the sigmoidal function depends on the indirect tensile strength(ITS) of the OGFC mixtures(which takes into account indirectly also the volumetrics and stiffness of the OGFC), whereas the evolutive translation factor depends on the age of the OGFC mixture. After excluding some outliers, the model was able to predict the measured TDC depth very well. Moreover, in-situ observations allowed a preliminary validation of the proposed model. This model can be used in pavement management systems(PMSs) to plan surface repairs due to TDC in a timely manner, thus minimizing pavement damage and maintenance costs.

关键词： Top-down cracking(TDC) Asphalt pavement Open-graded friction course(OGFC) Porous asphalt(PA) Pavement management system(PMS) Modelling

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Assessment of different Optimization Algorithms for a Thermal Conduction Problem

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Fluid Dynamics & Materials Processing 2023年第1期19卷 233-244页

作者： Mohammad Reza Hajmohammadi Javad Najafiyan Giulio Lorenzini Department of Mechanical engineering Amirkabir University of TechnologyTehranIran dipartimento di ingegneria e architettura UniversitàDegli Studi di ParmaParmaItaly

In this study,three computational approaches for the optimization of a thermal conduction problem are critically compared.These include a direct Method(DM),a Genetic Algorithm(GA),and a Pattern Search(PS)technique.The optimization aims to minimize the maximum temperature of a hot medium(a medium with uniform heat generation)using a constant amount of high conductivity materials(playing the role of fixed factor constraining the considered problem).The principal goal of this paper is to determine the most efficient and fastest option among the considered ones.It is shown that the examined three methods approximately lead to the same result in terms of maximum tem-perature.However,when the number of optimization variables is low,the DM is the fastest one.An increment in the complexity of the design and the number of degrees of freedom(DOF)can make the DM impractical.Results also show that the PS algorithm becomes faster than the GA as the number of variables for the optimization rises.

关键词： Optimization thermal conduction pattern search genetic algorithm

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experimental characterization of the 3D linear viscoelastic behavior of cold recycled bitumen emulsion mixtures

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Journal of Traffic and Transportation engineering(english edition) 2019年第4期6卷 324-336页

作者： Andrea Graziani Carlotta Godenzoni Francesco Canestrari dipartimento di ingegneria Civile Edile e Architettura Università Politecnica delle Marche

Cold mixtures with bitumen emulsion are produced at ambient temperature, leading to substantial reductions of energy consumption and atmospheric emissions. In cold recycling applications, cement is normally used to improve the mixture performance. Thus, the rheological behavior of cold recycled mixtures is different from that of conventional hot mixtures because it is due to the interaction of fresh bitumen, aged bitumen and cementitious bonds. In this study, we investigated the three-dimensional(3 D) linear viscoelastic(LVe) behavior of a cement-bitumen treated material(CBTM) mixture fabricated using bitumen emulsion and cement. For comparison, we also investigated the 3 D LVe behavior of hot-mix asphalt containing 25% of reclaimed asphalt and fabricated using polymermodified binder. Sinusoidal axial tests on cylindrical specimens, were carried out at various temperatures(from 0℃ to 50℃) and frequencies(from 0.1 to 12 Hz). The complex Young’s modulus e~*and the complex Poisson’s ratio v~*were determined through the measurement of axial and transverse strain. We show that when considering e*, CBTM mixtures may be considered thermo-rheologically simple and the Huet-Sayegh model can be used to simulate the frequencyetemperature dependence. On the other hand, when considering v*the behavior of CBTM mixtures is very different from that of hot mix asphalt. In particular, its absolute value is almost constant and very close to 0.15.

关键词： Bitumen emulsion Cold recycling Complex modulus Complex Poisson’s ratio Huet-Sayegh model

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Comparison of smart panels for tonal and broadband vibration and sound transmission active control

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International Journal of Smart and Nano Materials 2020年第4期11卷 431-484页

作者： Paolo Gardonio emanuele Turco Loris Dal Bo dipartimento Politecnico di ingegneria e architettura UniversitàDegli Studi Di UdineUdineItaly

This paper presents a comprehensive overview of the principal features of smart panels equipped with feed-forward and feedback systems for the control of the flexural response and sound transmission due respectively to tonal and to stochastic broadband disturbances.The smart panels are equipped with two types of actuators:first,distributed piezoelectric actuators formed either by small piezoelectric patches or large piezoelectric films bonded on the panels and second,point actuators formed by proof-mass electromagnetic transducers.Also,the panels encompass three types of sensors:first,small capacitive microphone sensors placed in front of the panels;second,distributed piezoelectric sensors formed by large piezoelectric films bonded on the panels and third point sensors formed by miniaturized accelerometers.The proposed systems implement both single-channel and multi-channel feed-forward and feedback control architectures.The study shows that,the vibration and sound radiation control performance of both feed-forward and feedback systems critically depends on the sensor-actuator configurations.

关键词： Active structural acoustic control active vibration control feed-forward control feedback control piezoelectric transducers proof-mass electromagnetic actuators

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A review of top-down cracking in asphalt pavements:Causes, models, experimental tools and future challenges

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Journal of Traffic and Transportation engineering(english edition) 2020年第5期7卷 541-572页

作者： Francesco Canestrari Lorenzo Paolo Ingrassia dipartimento di ingegneria Civile Edile e Architettura(DICEA)Uniuersita Politecnica delle MarcheAncona 60131Italy

In the last decades,a new type of distress has been observed more and more frequently on asphalt pavements.This distress,ascribable to fatigue failure,has been named top-down cracking(TDC) because it consists in longitudinal cracks that initiate on the pavement surface and then propagate downwards.A series of surveys recently carried out on Italian motorways highlighted that TDC can affect up to 20%-30% of the slow traffic lane.Therefore,in order to achieve a better understanding of such distress,this paper reviews causes,models and experimental tools and highlights future challenges for TDC.The literature review indicates that TDC can evolve on the pavement surface in three stages(i.e.,single crack,sister cracks,alligator cracking) and,below a certain depth,the cracks can form angles of 20°-40° with respect to the vertical plane.even though multiple factors contribute to TDC development,thick pavements are more likely to fail due to TDC induced by tire-pavement contact stresses,especially in the presence of open-graded friction courses(OGFCs).Moreover,in literature there are several TDC models based on mechanics(e.g.,fracture mechanics or continuum damage mechanics) which allow a rigorous study of crack initiation and propagation.Future challenges include the identification of a reliable and feasible test method,among those proposed in literature,to study the TDC performance of asphalt mixtures and the implementation of TDC in pavement management systems(PMSs) through the definition of criteria for TDC recognition in the field as well as for the rehabilitation depth evaluation.Finally,more research is needed for open-graded asphalt mixtures,which present critical drawbacks in terms of TDC.

关键词： Top-down cracking Flexible pavements Fatigue Cracking model Open-graded friction course Pavement management system

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Vibration suppression of speed-controlled robots with nonlinear control

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Frontiers of Mechanical engineering 2016年第2期11卷 204-212页

作者： Paolo BOSCARIOL Alessandro GASPAReTTO dipartimento Politecnico di ingegneria e architettura (DPIA) University of Udine Via delle Scienze 206 Udine 33100 Italy

在这份报纸，为追踪的同时的位置和机器人抑制的颤动的简单非线性的控制策略被介绍。控制为控制速度的伺服运动激活的设备被开发。为靠近环的系统的 asymptotic 稳定性的条件被保证它的被动导出。完成改进轨道追踪和颤动抑制的能力通过... 详细信息

在这份报纸，为追踪的同时的位置和机器人抑制的颤动的简单非线性的控制策略被介绍。控制为控制速度的伺服运动激活的设备被开发。为靠近环的系统的 asymptotic 稳定性的条件被保证它的被动导出。完成改进轨道追踪和颤动抑制的能力通过在一个三轴的笛卡儿的机器人上进行的试验性的测试被显示出。控制被瞄准与作为唯一的测量信号给联合位置的实现，减少的计算要求，和使用的简洁的很工业的应用程序兼容。

关键词：直角坐标机器人非线性控制策略速度控制振动抑制伺服驱动器位置跟踪渐近稳定性振动阻尼

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Chemical,morphological and rheological characterization of bitumen partially replaced with wood bio-oil:Towards more sustainable materials in road pavements

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Journal of Traffic and Transportation engineering(english edition) 2020年第2期7卷 192-204页

作者： Lorenzo Paolo Ingrassia Xiaohu Lu Gilda Ferrotti Francesco Canestrari dipartimento di ingegneria Civile Edile e Architettura(DICEA)Universita Politecnica delle MarcheAncona 60131Italy Nynas AB Nynashamn SE-14982Sweden

Nowadays,sustainability and circular economy are two principles to be pursued in all fields.In road pavement engineering,they can be put into practice through the partial substitution of bitumen with industrial residues and by-products deriving from renewable materials.Within this framework,this paper presents an extensive investigation of the chemical,morphological and rheological properties of bio-binders obtained by mixing a conventional 50/70 bitumen with different percentages by weight(0,5%,10%and 15%)of a renewable bio-oil,generated as a residue in the processing of wood into pulp and paper.Results show that overall the bio-oil provides a softening effect,which,in terms of performance,leads to an improvement of the low-temperature behaviour and fatigue resistance with respect to the control bitumen,in spite of an increased tendency to permanent deformation.Although no chemical reaction appears to occur after blending,the peculiarities of the bio-oil affect the chemistry of the resulting bio-binders,whereas no phase separation is observed from the microscopic analysis.In addition,a Newtonian behaviour,an unchanged temperature susceptibility and a good fitting of 1 S2 P1 D model to the rheological data are found,regardless of the bio-oil percentage considered.These promising outcomes suggest that such bio-binders can be favourably employed for several applications in road pavements.

关键词： Road materials Bio-binders FTIR SARA 1S2P1D Sustainability

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Strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

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Computer Modeling in engineering & Sciences 2023年第12期137卷 2149-2161页

作者： Stepan Konev Victor A.eremeyev Hamid M.Sedighi Leonid Igumnov Anatoly Bragov Aleksandr Konstantinov Ayaulym Kuanyshova Ivan Sergeichev Skolkovo Institute of Science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussia dipartimento di ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy Mechanical engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under compression.The test samples were manufactured through the filament winding of flat plates.To establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static tests.The samples were loaded both along and perpendicular to the direction of the reinforcing fiber.The applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during testing.As a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were obtained.Based on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are constructed.It is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under compression.An increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,respectively.Perpendicular loading resulted in a strength and elastic modulus increase by 58%and 50%,respectively.The average strength along the fibers at the largest studied strain rate was about 1000MPa.The obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength Split Hopkinson Pressure Bar compression

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