79 research outputs found

    Study and development of high release refractory materials for the SPES project

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    Throughout the last century, theoretical and experimental research made by the international nuclear physicists community has led to important advancement in the knowledge of the mechanisms that govern the behavior and stability of the nuclei. The technological improvements necessary to support this research has often opened the way to new applications in other field of science and industry which directly reflects in our common life experience. Nowadays, Europe is becoming more and more a leader in both theoretical and experimental nuclear physics, as testified by the presence on its territory of several institutes and laboratories dedicated to this field of research, like CERN (Organisation Européenne pour la Recherche Nucléaire), the world’s largest particle physics laboratory. Italy, represented mainly by INFN (Istituto Nazionale di Fisica Nucleare), is one of the main members of this community. One of the most important projects supported by INFN is SPES (Selective Production of Exotic Species), which aim is to develop a facility for the production of radioactive ion beams (RIBs) in one of the four national laboratories of INFN, LNL (Laboratori Nazionali di Legnaro). The facility is designed to produce and deliver to users both proton-rich and neutron-rich nuclei (range of mass 80-160 amu) to be used for nuclear physics research, as well as other applications in different fields of science. The generation of the aforementioned isotopes will occur inside a properly designed target, which represents the core of the whole project. The choice of the proper material for the target, both in terms of composition and properties, is of vital importance in determining the quantity and type of the produced isotopes. In this work, the synthesis and characterization of different types of target materials are presented. The results of experimental tests performed on some of the produced materials, in configurations very similar to those intended for the final SPES facility are also reported. Chapter 1 gives a general overview of the SPES project and its context whereas chapter 2 introduces the main topics related to the on-line behavior of the SPES target, relative to both its layout and to the properties of the material constituting it. Chapter 3 is focused on uranium carbide, which will be used at SPES to produce neutron-rich isotopes; after a description of its main physicochemical properties, the results of two on-line tests performed on target prototypes made of this material is reported and discussed into detail. In chapter 4 the synthesis methods and release-related properties of two potential materials to be used as SPES targets for the production of proton-rich isotopes, boron and lanthanum carbides, are presente

    Evaluating roughness scaling properties of natural active fault surfaces by means of multi-view photogrammetry

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    Fault roughness is a measure of the dimensions and distribution of fault asperities, which can act as stress concentrators affecting fault frictional behaviour and the dynamics of rupture propagation. Studies aimed at describing fault roughness require the acquisition of extremely detailed and accurate datasets of fault surface topography. Fault surface data have been acquired by methods such as LiDAR, laser profilometers and white light interferometers, each covering different length scales and with only LiDAR available in the field. Here we explore the potential use of multi-view photogrammetric methods in fault roughness studies, which are presently underexplored and offer the advantage of detailed data acquisition directly in the field. We applied the photogrammetric method to reproduce fault topography, by using seven dm-sized fault rock samples photographed in the lab, three fault surfaces photographed in the field, and one control object used to estimate the model error. We studied these topographies estimating their roughness scaling coefficients through a Fourier power spectrum method. Our results show scaling coefficients of 0.84 ± 0.17 along the slip direction and 0.91 ± 0.17 perpendicularly to it, and are thus comparable to those results obtained by previous authors. This provides encouragement for the use of photogrammetric methods for future studies, particularly those involving field-based acquisition, where other techniques have limitations

    Virtual Outcrops in a Pocket: The Smartphone as a Fully Equipped Photogrammetric Data Acquisition Tool

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    Since the advent of affordable consumer-grade cameras over a century ago, photographic images have been the standard medium for capturing and visualizing outcrop-scale geological features. Despite the ubiquity of raster image data capture in routine fieldwork, the development of close-range 3D remote-sensing techniques has led to a paradigm shift in the representation and analysis of rock exposures from two- to three-dimensional forms. The use of geological 3D surface reconstructions in routine fieldwork has, however, been limited by the portability, associated learning curve, and/or expense of tools required for data capture, visualization, and analysis. Smartphones are rapidly becoming a viable alternative to conventional 3D close-range remote-sensing data capture and visualization platforms, providing a catalyst for the general uptake of 3D outcrop technologies by the geological community, which were up until relatively recently the purview of a relatively small number of geospatial specialists. Indeed, the continuous improvement of smartphone cameras, coupled with their integration with global navigation satellite system (GNSS) and inertial sensors provides 3D reconstructions with comparable accuracy to survey-grade systems. These developments have already led many field geologists to replace reflex cameras, as well as dedicated handheld GNSS receivers and compass clinometers, with smartphones, which offer the equivalent functionality within a single compact platform. Here we demonstrate that through the use of a smartphone and a portable gimbal stabilizer, we can readily generate and register high-quality 3D scans of outcropping geological structures, with the workflow exemplified using a mirror of a seismically active fault. The scan is conducted with minimal effort over the course of a few minutes with limited equipment, thus being representative of a routine situation for a field geologist

    Photogrammetric 3D model via smartphone GNSS sensor. Workflow, error estimate, and best practices

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    Geotagged smartphone photos can be employed to build digital terrain models using structure from motion-multiview stereo (SfM-MVS) photogrammetry. Accelerometer, magnetometer, and gyroscope sensors integrated within consumer-grade smartphones can be used to record the orientation of images, which can be combined with location information provided by inbuilt global navigation satellite system (GNSS) sensors to geo-register the SfM-MVS model. The accuracy of these sensors is, however, highly variable. In this work, we use a 200 m-wide natural rocky cliff as a test case to evaluate the impact of consumer-grade smartphone GNSS sensor accuracy on the registration of SfM-MVS models. We built a high-resolution 3D model of the cliff, using an unmanned aerial vehicle (UAV) for image acquisition and ground control points (GCPs) located using a differential GNSS survey for georeferencing. This 3D model provides the benchmark against which terrestrial SfM-MVS photogrammetry models, built using smartphone images and registered using built-in accelerometer/gyroscope and GNSS sensors, are compared. Results show that satisfactory post-processing registrations of the smartphone models can be attained, requiring: (1) wide acquisition areas (scaling with GNSS error) and (2) the progressive removal of misaligned images, via an iterative process of model building and error estimation

    Early Evaluation of Copper Radioisotope Production at ISOLPHARM

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    The ISOLPHARM (ISOL technique for radioPHARMaceuticals) project is dedicated to the development of high purity radiopharmaceuticals exploiting the radionuclides producible with the future Selective Production of Exotic Species (SPES) Isotope Separation On-Line (ISOL) facility at the Legnaro National Laboratories of the Italian National Institute for Nuclear Physics (INFN-LNL). At SPES, a proton beam (up to 70 MeV) extracted from a cyclotron will directly impinge a primary target, where the produced isotopes are released thanks to the high working temperatures (2000 \ub0C), ionized, extracted and accelerated, and finally, after mass separation, only the desired nuclei are collected on a secondary target, free from isotopic contaminants that decrease their specific activity. A case study for such project is the evaluation of the feasibility of the ISOL production of 64Cu and 67Cu using a zirconium germanide target, currently under development. The producible activities of 64Cu and 67Cu were calculated by means of the Monte Carlo code FLUKA, whereas dedicated off-line tests with stable beams were performed at LNL to evaluate the capability to ionize and recover isotopically pure copper

    Study and development of high release refractory materials for the SPES project

    Get PDF
    Throughout the last century, theoretical and experimental research made by the international nuclear physicists community has led to important advancement in the knowledge of the mechanisms that govern the behavior and stability of the nuclei. The technological improvements necessary to support this research has often opened the way to new applications in other field of science and industry which directly reflects in our common life experience. Nowadays, Europe is becoming more and more a leader in both theoretical and experimental nuclear physics, as testified by the presence on its territory of several institutes and laboratories dedicated to this field of research, like CERN (Organisation Européenne pour la Recherche Nucléaire), the world’s largest particle physics laboratory. Italy, represented mainly by INFN (Istituto Nazionale di Fisica Nucleare), is one of the main members of this community. One of the most important projects supported by INFN is SPES (Selective Production of Exotic Species), which aim is to develop a facility for the production of radioactive ion beams (RIBs) in one of the four national laboratories of INFN, LNL (Laboratori Nazionali di Legnaro). The facility is designed to produce and deliver to users both proton-rich and neutron-rich nuclei (range of mass 80-160 amu) to be used for nuclear physics research, as well as other applications in different fields of science. The generation of the aforementioned isotopes will occur inside a properly designed target, which represents the core of the whole project. The choice of the proper material for the target, both in terms of composition and properties, is of vital importance in determining the quantity and type of the produced isotopes. In this work, the synthesis and characterization of different types of target materials are presented. The results of experimental tests performed on some of the produced materials, in configurations very similar to those intended for the final SPES facility are also reported. Chapter 1 gives a general overview of the SPES project and its context whereas chapter 2 introduces the main topics related to the on-line behavior of the SPES target, relative to both its layout and to the properties of the material constituting it. Chapter 3 is focused on uranium carbide, which will be used at SPES to produce neutron-rich isotopes; after a description of its main physicochemical properties, the results of two on-line tests performed on target prototypes made of this material is reported and discussed into detail. In chapter 4 the synthesis methods and release-related properties of two potential materials to be used as SPES targets for the production of proton-rich isotopes, boron and lanthanum carbides, are presentedNel corso dell’ultimo secolo, la ricerca teorica e sperimentale condotta dalla comunità internazionale in fisica nucleare ha portato ad importanti passi avanti nella comprensione dei meccanismi che governano il comportamento dei nuclei e della loro stabilità. In molti casi, le innovazioni tecnologiche che si sono rese necessarie per supportare tali ricerche hanno aperto la strada verso nuove applicazioni scientifiche ed industriali con ripercussioni dirette nella vita di tutti i giorni. Attualmente, l’Europa è sempre più leader nel campo della fisica nucleare, teorica e sperimentale, come testimoniato dalla presenza nel suo territorio di svariati istituti e laboratori dedicati a questa specifica area di ricerca, come ad esempio il CERN (Organisation Européenne pour la Recherche Nucléaire), il più grande laboratorio al mondo per la fisica delle particelle. L’Italia, principalmente rappresentata dall’INFN (Istituto Nazionale di Fisica Nucleare), è uno dei principali membri di questa comunità. Uno dei progetti più importanti finanziato dall’INFN è SPES (Selective Production of Exotic Species), la cui finalità è la costruzione di una facility per la produzione di fasci di ioni radioattivi, in uno dei quattro laboratori nazionali dell’INFN, LNL (Laboratori Nazionali di Legnaro). La facility è progettata per produrre e fornire agli utenti isotopi proton-rich e neutron-rich (massa compresa fra 80 e 160 amu) utilizzabili per esperimenti di fisica nucleare, ma anche per altre applicazioni in diversi settori scientifici. La formazione di tali isotopi avverrà all’interno di uno specifico bersaglio (target), che rappresenta il cuore dell’intero progetto. La scelta dell’opportuno materiale per il target, sia in termini di composizione che di proprietà è di vitale importanza nel determinare la quantità e tipo di isotopi prodotti. In questo lavoro, vengono descritte nel dettaglio la sintesi e caratterizzazione di diversi tipi di materiali proposti come target, ed inoltre vengono riportati i risultati di test sperimentali condotti su alcuni di essi, ottenuti in modalità molto simili a quelle a cui saranno sottoposti nella facility SPES. Il capitolo 1 fornisce una presentazione generale del progetto SPES e del contesto scientifico ad esso legato, mentre nel capitolo 2 viene descritto nel dettaglio il comportamento operativo del target SPES, con particolare riferimento alla sua geometria e alle proprietà del materiale che lo costituirà. Nel capitolo 3 vengono presentate le proprietà del materiale scelto come bersaglio per produrre isotopi neutron-rich, ovvero il carburo di uranio; vengono inoltre presentati i risultati di un test sperimentale di produzione di isotopi da parte di un prototipo di target SPES costituito di tale materiale. Il capitolo 4 descrive la sintesi e caratterizzazione di carburi di boro e lantanio, con particolare riferimento alle proprietà riconducibili alla capacità di rilascio di isotopi; tali materiali rappresentano dei potenziali target SPES per la produzione di isotopi proton-ric

    Extraction of 3D structural data from Virtual Outcrop Models: problems and best practices.

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    The rapid improvements of computer vision–based photogrammetric image processing pipelines (i.e., Structure from Motion–Multi View Stereophotogrammetry: SfM-MVS), coupled with the availability of various low-cost and portable acquisition tools, such as Digital Single-Lens Reflex (DSLR), mirrorless cameras, Unmanned Aerial Vehicle (UAV) and even smartphones, have revolutionized outcrop studies in structural geology and have brought traditional field geology into the digital age. This has had a transformative impact on Virtual Outcrop Models (VOMs), which have been promoted from mostly visualization media to fully interrogable quantitative objects. Among the several applications of VOMs in structural geology, extraction of near planar features (e.g., fracture and bedding surfaces) is one of the most important. Various procedures aimed at this purpose exist, spanning from fully automated segmentation and best fitting of point clouds to the manual picking of 3D polylines on both point clouds and textured meshes. Here we illustrate the pros and cons, best practices, and drawbacks of the main procedures for near planar geological data extraction from VOMs. While automated or supervised recognition and subsequent best-fitting of coplanar patches in point clouds has received remarkable attention, its application generally limits to rare case studies. Indeed, most commonly, geological outcrops do not expose patches of near planar surfaces which are large enough to carry out a robust best fitting, and the structural interpretation of the outcrop only permits manual picking procedures. In the latter case, the use of textured meshes must be preferred to point clouds, and during digitization the accuracy of the textured mesh must be considered, as well as the intrinsic roughness of any geological surfaces. The analysis of coplanarity and collinearity of the picked pointsets may help in identifying traces that diverge from idealized (low) collinear and (high) coplanar configurations. However, typically suggested threshold values often produce small datasets. Nonetheless, the goodness of the extraction of data based merely on the visual inspection of the best-fit plane, handling coplanarity and collinearity in real-time through live computation of best-fit planes from picked pointsets, is often acceptable

    Extraction of 3D structural data from Virtual Outcrop Models: problems and best practices.

    No full text
    The rapid improvements of computer vision–based photogrammetric image processing pipelines (i.e., Structure from Motion–Multi View Stereophotogrammetry: SfM-MVS), coupled with the availability of various low-cost and portable acquisition tools, such as Digital Single-Lens Reflex (DSLR), mirrorless cameras, Unmanned Aerial Vehicle (UAV) and even smartphones, have revolutionized outcrop studies in structural geology and have brought traditional field geology into the digital age. This has had a transformative impact on Virtual Outcrop Models (VOMs), which have been promoted from mostly visualization media to fully interrogable quantitative objects. Among the several applications of VOMs in structural geology, extraction of near planar features (e.g., fracture and bedding surfaces) is one of the most important. Various procedures aimed at this purpose exist, spanning from fully automated segmentation and best fitting of point clouds to the manual picking of 3D polylines on both point clouds and textured meshes. Here we illustrate the pros and cons, best practices, and drawbacks of the main procedures for near planar geological data extraction from VOMs. While automated or supervised recognition and subsequent best-fitting of coplanar patches in point clouds has received remarkable attention, its application generally limits to rare case studies. Indeed, most commonly, geological outcrops do not expose patches of near planar surfaces which are large enough to carry out a robust best fitting, and the structural interpretation of the outcrop only permits manual picking procedures. In the latter case, the use of textured meshes must be preferred to point clouds, and during digitization the accuracy of the textured mesh must be considered, as well as the intrinsic roughness of any geological surfaces. The analysis of coplanarity and collinearity of the picked pointsets may help in identifying traces that diverge from idealized (low) collinear and (high) coplanar configurations. However, typically suggested threshold values often produces small datasets. Nonetheless, the goodness of the extraction of data based merely on the visual inspection of the best-fit plane, handling coplanarity and collinearity in real-time through live computation of best-fit planes from picked pointsets, is often acceptable
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