Attivit C3 A0 nel settore delle Radiazioni Ionizza

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Ionizing Radiation Sources Applications ENEA-Casaccia Research Center S. BACCARO ENEA-FIM July 11, 2007

Ionizing Radiation Sources Applications : 

Ionizing Radiation Sources Applications Gamma radiation effects : irradiation tests at Calliope 60Co plant and related effects on materials; Nuclear Medicine that uses the nuclear properties of matter in diagnosis and therapy. Many procedures in nuclear medicine use radionuclides, or pharmaceuticals that have been labeled with radionuclides (radiopharmaceuticals).

Irradiation technologies : 

Irradiation technologies Dosimetry

Effects of radiation: 

60Co PLANT LABORATORY Effects of radiation Chemical physical analysis

Calliope 60Co radioisotope source : 

Calliope 60Co radioisotope source Rack with 60Co sources Available dosimetry methods: 1) Fricke absolute dosimetry (20-400 Gy); 2) Alanine dosimetry (1 Gy-500 kGy); 3) Red Perspex dosimetry (5-40 kGy).


Unseismic system Laboratory area Ozone control system Optical laboratory Control room Control consolle CALLIOPE plant

Dosimetric methods at CALLIOPE plant: 

Spectrophotometer UV-VIS Spectrophotometer UV-VIS And radiocromic analyser (510-600 nm) g 50 G Dosimetric methods at CALLIOPE plant


To map the  radiation field inside the irradiation cell, we have performed a simulation of Calliope dose rate profile by using FLUKA code. Such code includes a good description of the electromagnetic physics down to about 1\,keV and its models are adapted and extended versions of the EGS4 shower code. Simulation of  radiation field inside the cell. Top view x-y of the dose rate profile in the overall irradiation cell Simulation results of the radiation field inside the 60Co pencil rack and in the region closest to the source. Thanks to this simulation, we can easy check the dose rate values requested to perform tests and before to start with experimental activity we can verify by dosimeters the dose rate position in the plant.


Interaction of -rays with matter Interaction of  rays with the matter Secondary processes: the Auger emission and fluorescence (in the photoelectric effect), recoil electrons emission (Compton effect), positron annihilation (pair production).

Radiation effects on polymers: 

Degradation Cross-linking Industrial Applications Radiation effects on polymers Ionising radiation


Characterization of polymers under  irradiation: spectroscopic and mechanical measurements The Electron Paramagnetic Resonance (EPR) spectroscopy is based on the magnetic properties of free radicals, which are chemical species containing an unpaired electron in the outer orbital.


Structure: It is made by very small graphite lamellae arranged in a disordered way. When carbon black is used as filler it binds to rubber PHYSICAL COMPONENT & CHEMICAL COMPONENT Carbon black Attempt to increase the “chemical component” of the Bound Rubber mechanism by  radiation.


The EPR signal depends on the dose and on the dose rate Radical fading after the stop of irradiation At the ~ 500 kGy irradiation dose, both the ESR signal intensity and the Bdr are maximum indicating a clear correlation between radiation induced sensitization and Bdr phenomenon


Possibility of enhance carbon substrates performances, related to platinum deposition, using gamma radiation Morphology, electrochemical and electrocatalytic behaviour of nanostructured Pt deposits Gamma radiation induced free radical concentration on carbon materials (carbon powder and multiwalled carbon nanotubes) used as substrates were studied by EPR spectroscopy. RADIATION EFFECTS ON PLATINUM NANOSTRUCTURED ELECTROCATALYSTS FOR POLYMER ELECTROLYTE FUEL CELLS Polymer Electrolyte Fuel Cells (PEFCs) low weight and high power density


SCINTILLATOR + LIGHT DETECTOR = DETECTOR Excited state Fundamental state Parameters Density, Emission spectrum, Light yield, Molière radius, Radiation length, Radiation hardness, Hygroscopicity.

Application of Scintillators: 

Application of Scintillators Medical treatment




Possible formation of colour centres which absorb photons emitted by luminescent centres.


Measurement method investigate the radiation induced damage of scintillating crystals. UV-visible optical absorption spectroscopy


Radiation doses (10 years) g Dose n Flux ECAL crystals <5 kGy 2 10 13 n/cm2 PROTON – PROTON Beam energy 7 TeV Energy at the collision = 14 TeV Higgs boson associates with Higgs field to solve the question: “why elementary particles have mass and their masses are different?”


YAG:Ce3+ POSSIBILITY TO REDUCE point defects by aliovalent doping:


Glassy scintillators Bulk Fibre forms For X-rays and neutron detection PROPERTIES


Chalcogenide Glasses and ZnO based scintillating glasses Nano-crystallized glasses Rare earth doped glasses -irradiation induced effects on glasses


Irradiation Resistance Transmitting spectra before and afterγ irradiation of ZnO based and Ce3+-doped glasses


Radiation resistance of novel PbO-free glasses PbO containing glass systems have become popular as commercial radiation shielding and low temperature sinterable materials due to their high density, high structural stability, low glass transition temperature and good thermal and electrical characteristics. However, these materials contain PbO (typical PbO content is 50 mol% or >70 wt%), a component with deleterious health and environmental effects. Recent environmental regulations have restricted the wide use of PbO systems. Thus developing Pb-free or Pb-saving materials has been undertaken. In the present project, Bi2O3, BaO and ZnO have been considered as candidate materials to replace PbO. γ-radiation Effects on luminescent glasses or glass-ceramics for white LED applications White-light LEDs show high potential for replacement of conventional lighting sources with the advantage of the longer lifetime, lower energy consumption, and environmental-friendly characteristics. Since the glass or glass-ceramic can be formed in a plate-like shape, developing luminescent glass to substitute phosphor is of great significance to realize resin free white LED devices. The present work aims at preparation of glass or glass-ceramic which emits the mixed blue and yellow light by itself and has the excitation spectra being well matched with the emission spectra of UV LED chip.


The radiation damage induced on silicon based detectors underwent several studies since from 1950. Recently, the advent of has increased the interest in the analysis of radiation-induced damage on electronic devices.

AlphaMagnetic Spectrometer : 

AlphaMagnetic Spectrometer Collaboration at INFN Section of Roma1 AMS Roma1 Participants: INFN, University of Rome “La Sapienza”,ENEA Transition Radiation Detector Orbit: 350 km altitude Dose rate 10 Gy/year

Effects of irradiation on electronic devices: 

 damage mechanisms  Effects dose-rate  T effects on damage mechanisms Space radiation Shielding: 1.5 mmPb & 0.7mmAl D(Si) =0.9D(Fricke) T=100°C per 168h Effects of irradiation on electronic devices


Radiation damage qualification of electronic devices * Importance of the radiation induced damage on electronic devices; * Qualification of radiation damage at irradiation facilities: * Ionization & Displacement Damage


Devices used in Space experiments are also exposed to the passage of highly energetic particles: The flux of GCR with energy < 1 GeV is affected by the sun’s 11 years cycle: GCR flux enters the solar system interacting with the solar wind and it is partially attenuated.


Solar particles events: high fluxes of charged particles encountered during rare but intense coronal mass ejections and solar flares (electrons, protons, heavy charged particles up to iron). J.Barth, NASA


Van Allen Belts: energetic electron and protons trapped in the geomagnetic field and making up the Earth’s radiation Belts.


For space vehicles or satellites Earth Orbiting Missions Typical radiation levels < 20 krad (Si) (altitude, inclination, SAA)


BEFORE IRRADIATION - e--h creation and separation - e- drift outside the oxide - h migration and trapping in the near the Si-SiO2 interface AFTER IRRADIATION g


Displacement damage: Caused by lattice collisions between energetic protons or electrons that transfer sufficient energy to the lattice to move an atom out of its normal position.


ESA/SCC BASIC SPECIFICATION No. 22900 MIL-STD-883E Irradiation tests of electronic devices can be performed according to:


50< dose rate <300 rads(Si)/s (0.5 and 3 Gy(Si)/s)  10% Two dose rate windows: 1)The standard dose rate: 3.6 krad to 36 krad/h (36 to 360 Gy/h); 2) The low dose rate: 36 to 360 rad/h (0.36 to 3.6 Gy/h) ESA/SCC BASIC SPECIFICATION No. 22900 MIL-STD-883E IONIZATION DAMAGE QUALIFICATION -Total exposition time<96 hours. -Post irradiation electrical characterization within 1 hour of completion of exposure. -Time interval between one completed exposition and the beginning of the next exposition should be < 2 hours. -Accelerated ageing under bias: 100 °C under bias for 168 hours.


Nell'ambito delle attività commissionate da Sogin (specifica tecnica Sogin SL CX 004 del 11/06/2004), la Nucleco S.p.A., in data 23/06/2004, ha dato inizio, presso il laboratorio TLA del centro di ricerche Casaccia, alle attività sperimentali finalizzate alla prequalificazione del prodotto finale della cementazione ("waste form"). Il progetto sperimentale è stato articolato in diverse fasi: Preparazione delle soluzioni simulanti i rifiuti radioattivi; Preparazione di miscele cementizie e conduzione di prove e misure (sia sugli impasti che sui provini) per la prequalificazione di una o più matrici di condizionamento. Le attività sperimentali svolte dalla Nucleco S.p.A. sono finalizzate all'individuazione e alla validazione della migliore possibile composizione della matrice cementizia Test di irraggiamento su cementi per inglobamento di scorie


Dopo un processo di trattamento, i rifiuti  vengono inglobati in matrici,  la cui natura dipende dal tipo di rifiuto, dalla sua attività e dai criteri di accettabilità previsti per lo smaltimento finale.  I rifiuti di bassa attività vengono condizionati mediante l'inglobamento in matrice cementizia o più raramente in matrice bituminosa. Il manufatto finale consiste in un fusto cementato le cui dimensioni standard sono di 220, 400 o 500 litri. Nel caso di inglobamento di residui costituiti da componenti di impianto voluminosi (tubazioni, strumenti contaminati, ecc) vengono prodotti manufatti costituiti da cassoni cementati di grandi dimensioni (10 metri cubi ed oltre). I rifiuti ad alta attività vengono sottoposti ad un processo di vetrificazione che consiste nell'inglobamento in blocchi vetrosi per fusione ad alta temperatura (oltre 1000°C). Il manufatto finale è costituito da un contenitore in acciaio (generalmente di circa 50 cm di diametro e 120 cm di altezza) nel quale viene colato il vetro contenente i rifiuti. 


Le soluzioni di simulazione vengono preparate avendo cura di rappresentare tutti i componenti chimici che, direttamente o indirettamente, possono assumere rilevanza sia nella gestione dei rifiuti che sulle caratteristiche di durabilità della "waste form". per la simulazione si parte dalla composizione chimica (limitata ai macro componenti, cioè quelli che, per la loro concentrazione, possono influire in modo significativo sulla scelta e sulla composizione della matrice cementizia di solidificazione e quindi sulla qualità del prodotto finale cementato) Radioactive wastes solidified in concrete Resistenza a compressione richiesta non inferiore a 500 N/cm2


IRRADIATION TEST In accordance with the requirements of Waste form Technical Position (United States Nuclear Regulatory Commission), irradiation testing of solidified waste forms should be conducted on specimens exposed to a minimum dose of 10E+8 rads. The 10E+8 rads radiation dose is approximately equivalent to the dose that would be acquired by a waste form over a 300-year period, if the waste form were loaded to a Cesium-137 or Strontium-90 concentration of 10 Ci/cu.ft. Cu.ft x 0.0283 m3 10 Ci /0.0283 m3 10 Ci/litre in concrete = 108 rad in 300 Years


This is recommended maximum activity level for organic resins based on evidence that while a measurable amount of damage to the resin will occur at 10E+8 rads, the amount of damage will have negligible effect on power plant or disposal site safety. However, cementitious materials are not affected by gamma radiation to relatively high cumulative doses (e.g. greater than 10E+9 rads) considerably in excess of 10E+8 rads. Therefore, for cement-stabilizated waste forms, irradiation qualification testing need not be conducted unless the waste form contain ion exchange resins or other organic media or the expected cumulative dose on waste forms containing other materials is greater than 10E+9 rads.


Testing should be performed on specimens exposed to 10E+8 rads or the expected maximum dose greater than 10E+8 rads for waste forms that contain ion exchange resins or other organic media or the expected maximum dose greater than 10E+9 rads for other waste forms. In cases where irradiation testing is warranted, a minimum of three specimens should be tested for each waste formulation being qualified. Following the irradiation exposure the specimens should be examined visually and should be free of any evidence of significant cracking, spalling, or bulk disintegration; i.e., visible evidence of significant degradation would be indicative of failure of the irradiation test. If there are no significant visible defects the test specimens should be subjected to compressive strength testing in accordance with ASTM C39.

Radiation effects on biologic systems: 

Montreal Protocol (1991): Fumigant abolition Cultural Heritage Disinfection/Disinfesting books and archive documents (Dose 3-5 kGy) Agriculture Sterilization (Dose 25 kGy) Radiation effects on biologic systems

Programma sperimentale per disinfezione e disinfestazione di archivi cartacei: 

Trasferimento tecnologico Messa a punto del processo Ministero Beni Culturali Industrie di settore Emanazione norme applicative per materiale bibliografico e documentale Programma sperimentale per disinfezione e disinfestazione di archivi cartacei

Attività di ricerca su archivi cartacei: 

Collaborazione con l’Istituto Centrale per la Patologia del Libro e l’Istituto Poligrafico e Zecca dello Stato . Attività di ricerca su archivi cartacei

Effetto dei raggi g su vari substrati Dose ottimale: 2-3 kGy: 

Cellulosa Carta permanente Funghi microscopici cellulosolitici Radioresistenza Raggi g, trattamenti in atmosfera controllata e invecchiamento termico Raggi g Effetto dei raggi g su vari substrati Dose ottimale: 2-3 kGy Ciclo biologico Sopravvivenza Fertilità Muta Malformazioni Inchiostri


Isotopi attivi 32P, 90Y e 188Re in un multistrato brevettato per il tumore della pelle, e il complesso DMSA-99mTc(V) contenente tecnezio pentavalente con Sn(II) e acido dimercaptosuccinico per diagnosi e terapia della metastasi ossee da carcinoma prostatico. Medicina nucleare Risparmiare il tessuto sano raggiungere ed aderire alle zone interessate patologia tumorale Distruggere la massa patogena Messa a punto di tecniche complesse che utilizzano isotopi gamma emittenti (131I e 99mTc) in vettori specifici per la cura del tumore della vescica.

Kit diagnostico per la determinazione della ioduria (commercializzato CELLTECH, brevetto ENEA) : 

Kit diagnostico per la determinazione della ioduria (commercializzato CELLTECH, brevetto ENEA) La determinazione dello iodio nei fluidi biologici e nell’urina in particolare è il mezzo principale per scoprire carenze o eccessi nutrizionali e/o patologici di Iodio nell’organismo cosi come nella terapia dei tumori tiroidei, ove viene effettuata una distruzione dei tessuti tiroidei per irraggiamento selettivo con 131I (radioablazione). Kit diagnostico per la determinazione non strumentale (titolazione cronocolorimetrica). Tale kit è attualmente commercializzato in un gran numero di Ospedali italiani dalla azienda CELLTECH, e la metodica della ioduria è stata inserita in alcuni tariffari sanitari regionali.


E’ stato realizzato e brevettato un procedimento che consente un irraggiamento selettivo di tumori della pelle (basaliomi e carcinomi a cellule squamose) mediante un multistrato beta emittente.

Sviluppi futuri: 

Sviluppi futuri Caratterizzazione metrologica sugli isotopi di interesse con validazione e taratura della strumentazione medica. Programmi per il calcolo dosimetrico con isotopi beta emittenti e calcolo di autoassorbimenti in diversi tessuti. Metodi di misura di dose con risoluzione del sub-millimetro su tessuti simulati ed umani, e relativa validazione sperimentale. Identificazione di strumentazione per scintigrafia ad alta risoluzione, in particolare per tumori vescicali e brachiterapia post-angioplastica.



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