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Serianni G, Toigo V, Bigi M, Boldrin M, Chitarin G, Dal Bello S, Grando L, Luchetta A, Marcuzzi D, Pasqualotto R, Pomaro N, Zaccaria P, Zanotto L, Agostinetti P, Agostini M, Antoni V, Aprile D, Barbisan M, Battistella M, Brombin M, Cavazzana R, Dalla Palma M, Dan M, De Lorenzi A, Delogu R, De Muri M, Denizeau S, Fadone M, Fellin F, Ferbel L, Ferro A, Gaio E, Gambetta G, Gasparini F, Gnesotto F, Jain P, Maistrello A, Manduchi G, Manfrin S, Marchiori G, Marconato N, Moresco M, Patton T, Pavei M, Peruzzo S, Pilan N, Pimazzoni A, Piovan R, Poggi C, Recchia M, Rizzolo A, Rostagni G, Sartori E, Siragusa M, Sonato P, Spada E, Spagnolo S, Spolaore M, Taliercio C, Tinti P, Ugoletti M, Valente M, Zamengo A, Zaniol B, Zaupa M, Baltador C, Cavenago M, Boilson D, Rotti C, Veltri P, Bonicelli T, Paolucci F, Muriel S, Masiello A, Chakraborty A, Patel H, Singh N, Fantz U, Heinemann B, Kraus W, Kashiwagi M, Tsumori K. SPIDER in the roadmap of the ITER neutral beams. FUSION ENGINEERING AND DESIGN 2019. [DOI: 10.1016/j.fusengdes.2019.04.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Siragusa M, Sonato P, Visentin M, Mura M, Siviero F, Viale L, Maccallini E, Day C, Hanke S, Sartori E. Conceptual design of scalable vacuum pump to validate sintered getter technology for future NBI application. FUSION ENGINEERING AND DESIGN 2019. [DOI: 10.1016/j.fusengdes.2018.11.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Cavenago M, Serianni G, Baltador C, Barbisan M, De Muri M, Pimazzoni A, Poggi C, Veltri P, Aprile D, Antoni V, Armelao L, Baseggio L, Candeloro V, Cervaro V, Franchin L, Jain P, Laterza B, Maniero M, Martini D, Minarello A, Pasqualotto R, Rancan M, Ravarotto D, Recchia M, Sartori E, Sattin M, Ugoletti M, Variale V, Zucchetti S. Experimental experience and improvement of NIO1 H− ion source. FUSION ENGINEERING AND DESIGN 2019. [DOI: 10.1016/j.fusengdes.2019.01.071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Siviero F, Caruso L, Porcelli T, Mura M, Maccallini E, Manini P, Sartori E, Siragusa M, Day C, Sonato P. Characterization of ZAO® sintered getter material for use in fusion applications. FUSION ENGINEERING AND DESIGN 2019. [DOI: 10.1016/j.fusengdes.2019.03.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Lebrun C, Vukusic S, Abadie V, Achour C, Ader F, Alchaar H, Alkhedr A, Andreux F, Androdias G, Arjmand R, Audoin B, Audry D, Aufauvre D, Autreaux C, Ayrignac X, Bailbe M, Benazet M, Bensa C, Bensmail D, Berger E, Bernady P, Bertagna Y, Biotti D, Blanchard-Dauphin A, Bonenfant J, Bonnan M, Bonnemain B, Borgel F, Botelho-Nevers E, Boucly S, Bourre B, Boutière C, Branger P, Brassat D, Bresch S, Breuil V, Brochet B, Brugeilles H, Bugnon P, Cabre P, Camdessanché JP, Carra-Dalière C, Casez O, Chamouard JM, Chassande B, Chataignier P, Chbicheb M, Chenet A, Ciron J, Clavelou P, Cohen M, Colamarino R, Collongues N, Coman I, Corail PR, Courtois S, Coustans M, Creange A, Creisson E, Daluzeau N, Davenas C, De Seze J, Debouverie M, Depaz R, Derache N, Divio L, Douay X, Dulau C, Durand-Dubief F, Edan G, Elias Z, Fagniez O, Faucher M, Faucheux JM, Fournier M, Gagneux-Brunon A, Gaida P, Galli P, Gallien P, Gaudelus J, Gault D, Gayou A, Genevray M, Gentil A, Gere J, Gignoux L, Giroux M, Givron P, Gout O, Grimaud J, Guennoc AM, Hadhoum N, Hautecoeur P, Heinzlef O, Jaeger M, Jeannin S, Kremer L, Kwiatkowski A, Labauge P, Labeyrie C, Lachaud S, Laffont I, Lanctin-Garcia C, Lannoy J, Lanotte L, Laplaud D, Latombe D, Lauxerois M, Le Page E, Lebrun-Frenay C, Lejeune P, Lejoyeux P, Lemonnier B, Leray E, Loche CM, Louapre C, Lubetzki C, Maarouf A, Mada B, Magy L, Maillart E, Manchon E, Marignier R, Marque P, Mathey G, Maurousset A, Mekies C, Merienne M, Michel L, Milor AM, Moisset X, Montcuquet A, Moreau T, Morel N, Moussa M, Naudillon JP, Normand M, Olive P, Ouallet JC, Outteryck O, Pacault C, Papeix C, Patry I, Peaureaux D, Pelletier J, Pichon B, Pittion S, Planque E, Pouget MC, Pourcher V, Radot C, Robert I, Rocher F, Ruet A, Ruet A, Saint-Val C, Salle JY, Salmon A, Sartori E, Schaeffer S, Stankhof B, Taithe F, Thouvenot E, Tizon C, Tourbah A, Tourniaire P, Vaillant M, Vermersch P, Vidil S, Wahab A, Warter MH, Wiertlewski S, Wiplosz B, Wittwer B, Zaenker C, Zephir H. Immunization and multiple sclerosis: Recommendations from the French Multiple Sclerosis Society. Rev Neurol (Paris) 2019; 175:341-357. [DOI: 10.1016/j.neurol.2019.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 03/31/2019] [Accepted: 04/11/2019] [Indexed: 10/26/2022]
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Antoni V, Taccogna F, Agostinetti P, Barbisan M, Cavenago M, Chitarin G, Ferron N, Minelli P, Pimazzoni A, Poggi C, Sartori E, Serianni G, Suweis S, Ugoletti M, Veltri P. Negative ion beam source as a complex system: identification of main processes and key interdependence. RENDICONTI LINCEI. SCIENZE FISICHE E NATURALI 2019. [DOI: 10.1007/s12210-019-00798-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Budui S, Bigolin F, Giordano F, Leoni S, Berteotti M, Sartori E, Franceschini L, Taddei M, Salvetti S, Castiglioni F, Gilli F, Skafidas S, Schena F, Petroni ML, Busetto L. Effects of an Intensive Inpatient Rehabilitation Program in Elderly Patients with Obesity. Obes Facts 2019; 12:199-210. [PMID: 30928989 PMCID: PMC6547270 DOI: 10.1159/000497461] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 02/04/2019] [Indexed: 12/17/2022] Open
Abstract
OBJECTIVE The aim of this study was to assess the short-term effectiveness of an intensive inpatient multidimensional rehabilitation program (MRP), including diet, exercise, and behavioral therapy, in elderly patients with severe obesity. METHODS Forty-four elderly patients (old; age 69.3 ± 3.5 years, BMI 41.9 ± 14.9) were analyzed against 215 younger patients (young; age 48.2 ± 18.5 years, BMI 43.9 ± 9.4), who were used as controls. All patients underwent MRP, based on group therapy guided by a multidisciplinary team (physicians, dietitians, exercise trainers, psychologists). We evaluated changes in anthropometry, cardiovascular risk factors, physical fitness, quality of life, and eating behavior. RESULTS After 3 weeks of MRP, we observed a reduction in body weight (old -3.8%, young -4.3%), BMI (old -3.9%, young -4.4%), waist circumference (old -3.4%, young -4.1%), total cholesterol (old -14.0%, young -15.0%), and fasting glucose (old -8.3%, young -8.1%), as well as improved performance in the Six-Minute-Walk Test (old +28.7%, young +15.3%), chair-stand test (old +24.8%, young +26.9%), and arm-curl test (old +15.2%, young +27.3%). Significant improvement was registered in all other analyzed domains. CONCLUSION Our 3-week MRP provided significant clinical and functional improvement, which was similar between elderly and younger patients with severe obesity. In the long-term, this may be translated into better quality of life, through better management of obesity-associated morbidities and reduced frailty.
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Dalla Palma M, Sartori E, Zaupa M, Pasqualotto R. Simulation of the beamline thermal measurements to derive particle beam parameters in the ITER neutral beam test facility. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:10J111. [PMID: 30399762 DOI: 10.1063/1.5038952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Injection of high energy neutral beam particles will be used in the ITER experiment for plasma heating and current drive. In a ITER heating beam injector, a 40 MW electrostatically accelerated negative beam will be neutralised and filtered along the beamline, obtaining a nominal 16.5 MW neutral beam power to be injected in the tokamak plasma or intercepted during conditioning and commissioning. The beam will heat the actively cooled panels of the beamline components with up to 13 MW/m2 surface power density and 18 MW power. These extreme conditions require testing in a ITER full scale neutral beam test facility under construction in Padova where the temperature of the beamline components will be monitored by 610 embedded thermocouples for protection against critical conditions, for recognising beam conditioning, and for deriving beam parameters. Power density maps of the expected beam-component interactions are applied on a parametric non-linear finite element model to simulate fields of expected temperatures. Such thermal maps are analyzed to derive the beam parameters during operation: divergence of 3-7 mrad and misalignment of 0-3 mrad. The sensibility of the temperature measurements is discussed considering a minimum 10% fraction of the nominal beam power.
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Toigo V, Piovan R, Dal Bello S, Gaio E, Luchetta A, Pasqualotto R, Zaccaria P, Bigi M, Chitarin G, Marcuzzi D, Pomaro N, Serianni G, Agostinetti P, Agostini M, Antoni V, Aprile D, Baltador C, Barbisan M, Battistella M, Boldrin M, Brombin M, Dalla Palma M, De Lorenzi A, Delogu R, De Muri M, Fellin F, Ferro A, Finotti C, Fiorentin A, Gambetta G, Gnesotto F, Grando L, Jain P, Maistrello A, Manduchi G, Marconato N, Moresco M, Ocello E, Pavei M, Peruzzo S, Pilan N, Pimazzoni A, Recchia M, Rizzolo A, Rostagni G, Sartori E, Siragusa M, Sonato P, Sottocornola A, Spada E, Spagnolo S, Spolaore M, Taliercio C, Valente M, Veltri P, Zamengo A, Zaniol B, Zanotto L, Zaupa M, Boilson D, Graceffa J, Svensson L, Schunke B, Decamps H, Urbani M, Kushwah M, Chareyre J, Singh M, Bonicelli T, Agarici G, Masiello A, Paolucci F, Simon M, Bailly-Maitre L, Bragulat E, Gomez G, Gutierrez D, Mico G, Moreno JF, Pilard V, Kashiwagi M, Hanada M, Tobari H, Watanabe K, Maeshima T, Kojima A, Umeda N, Yamanaka H, Chakraborty A, Baruah U, Rotti C, Patel H, Nagaraju M, Singh N, Patel A, Dhola H, Raval B, Fantz U, Heinemann B, Kraus W, Hanke S, Hauer V, Ochoa S, Blatchford P, Chuilon B, Xue Y, De Esch H, Hemsworth R, Croci G, Gorini G, Rebai M, Muraro A, Cavenago M, D'Arienzo M, Sandri S. A substantial step forward in the realization of the ITER HNB system: The ITER NBI Test Facility. FUSION ENGINEERING AND DESIGN 2017. [DOI: 10.1016/j.fusengdes.2016.11.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Furlan L, Contiero B, Chiarini F, Colauzzi M, Sartori E, Benvegnù I, Fracasso F, Giandon P. Risk assessment of maize damage by wireworms (Coleoptera: Elateridae) as the first step in implementing IPM and in reducing the environmental impact of soil insecticides. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:236-251. [PMID: 27709433 PMCID: PMC5219023 DOI: 10.1007/s11356-016-7692-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 09/12/2016] [Indexed: 05/27/2023]
Abstract
A survey of maize fields was conducted in northeast Italy from 1986 to 2014, resulting in a dataset of 1296 records including information on wireworm damage to maize, plant-attacking species, agronomic characteristics, landscape and climate. Three wireworm species, Agriotes brevis Candeze, A. sordidus Illiger and A. ustulatus Schäller, were identified as the dominant pest species in maize fields. Over the 29-year period surveyed, no yield reduction was observed when wireworm plant damage was below 15 % of the stand. A preliminary univariate analysis of risk assessment was applied to identify the main factors influencing the occurrence of damage. A multifactorial model was then applied by using the significant factors identified. This model allowed the research to highlight the strongest factors and to analyse how the main factors together influenced damage risk. The strongest factors were: A. brevis as prevalent damaging species, soil organic matter content >5 %, rotation including meadows and/or double crops, A. sordidus as prevalent damaging species, and surrounding landscape mainly meadows, uncultivated grass and double crops. The multifactorial model also showed how the simultaneous occurrence of two or more of the aforementioned risk factors can conspicuously increase the risk of wireworm damage to maize crops, while the probability of damage to a field with no-risk factors is always low (<1 %). These results make it possible to draw risk maps to identify low-risk and high-risk areas, a first step in implementing bespoke IPM procedures in an attempt to reduce the impact of soil insecticides significantly.
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Sartori E, Panasenkov A, Veltri P, Serianni G, Pasqualotto R. Study of a high power hydrogen beam diagnostic based on secondary electron emission. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:11D438. [PMID: 27910602 DOI: 10.1063/1.4960313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In high power neutral beams for fusion, beam uniformity is an important figure of merit. Knowing the transverse power profile is essential during the initial phases of beam source operation, such as those expected for the ITER heating neutral beam (HNB) test facility. To measure it a diagnostic technique is proposed, based on the collection of secondary electrons generated by beam-surface and beam-gas interactions, by an array of positively biased collectors placed behind the calorimeter tubes. This measurement showed in the IREK test stand good proportionality to the primary beam current. To investigate the diagnostic performances in different conditions, we developed a numerical model of secondary electron emission, induced by beam particle impact on the copper tubes, and reproducing the cascade of secondary emission caused by successive electron impacts. The model is first validated against IREK measurements. It is then applied to the HNB case, to assess the locality of the measurement, the proportionality to the beam current density, and the influence of beam plasma.
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Zaupa M, Dalla Palma M, Sartori E, Brombin M, Pasqualotto R. SPIDER beam dump as diagnostic of the particle beam. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:11D415. [PMID: 27910661 DOI: 10.1063/1.4958906] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The beam power produced by the negative ion source for the production of ion of deuterium extracted from RF plasma is mainly absorbed by the beam dump component which has been designed also for measuring the temperatures on the dumping panels for beam diagnostics. A finite element code has been developed to characterize, by thermo-hydraulic analysis, the sensitivity of the beam dump to the different beam parameters. The results prove the capability of diagnosing the beam divergence and the horizontal misalignment, while the entity of the halo fraction appears hardly detectable without considering the other foreseen diagnostics like tomography and beam emission spectroscopy.
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Dalla Palma M, Pasqualotto R, Sartori E, Spagnolo S, Spolaore M, Veltri P. In-vacuum sensors for the beamline components of the ITER neutral beam test facility. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:11D417. [PMID: 27910334 DOI: 10.1063/1.4959954] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Embedded sensors have been designed for installation on the components of the MITICA beamline, the prototype ITER neutral beam injector (Megavolt ITER Injector and Concept Advancement), to derive characteristics of the particle beam and to monitor the component conditions during operation for protection and thermal control. Along the beamline, the components interacting with the particle beam are the neutralizer, the residual ion dump, and the calorimeter. The design and the positioning of sensors on each component have been developed considering the expected beam-surface interaction including non-ideal and off-normal conditions. The arrangement of the following instrumentation is presented: thermal sensors, strain gages, electrostatic probes including secondary emission detectors, grounding shunt for electrical currents, and accelerometers.
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Calura E, Paracchini L, Fruscio R, DiFeo A, Ravaggi A, Peronne J, Martini P, Sales G, Beltrame L, Bignotti E, Tognon G, Milani R, Clivio L, Dell'Anna T, Cattoretti G, Katsaros D, Sartori E, Mangioni C, Ardighieri L, D'Incalci M, Marchini S, Romualdi C. A prognostic regulatory pathway in stage I epithelial ovarian cancer: new hints for the poor prognosis assessment. Ann Oncol 2016; 27:1511-9. [PMID: 27194815 DOI: 10.1093/annonc/mdw210] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 05/11/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Clinical and pathological parameters of patients with epithelial ovarian cancer (EOC) do not thoroughly predict patients' outcome. Despite the good outcome of stage I EOC compared with that of stages III and IV, the risk assessment and treatments are almost the same. However, only 20% of stage I EOC cases relapse and die, meaning that only a proportion of patients need intensive treatment and closer follow-up. Thus, the identification of cell mechanisms that could improve outcome prediction and rationalize therapeutic options is an urgent need in the clinical practice. PATIENTS AND METHODS We have gathered together 203 patients with stage I EOC diagnosis, from whom snap-frozen tumor biopsies were available at the time of primary surgery before any treatment. Patients, with a median follow-up of 7 years, were stratified into a training set and a validation set. RESULTS AND CONCLUSIONS Integrated analysis of miRNA and gene expression profiles allowed to identify a prognostic cell pathway, composed of 16 miRNAs and 10 genes, wiring the cell cycle, 'Activins/Inhibins' and 'Hedgehog' signaling pathways. Once validated by an independent technique, all the elements of the circuit resulted associated with overall survival (OS) and progression-free survival (PFS), in both univariate and multivariate models. For each patient, the circuit expressions have been translated into an activation state index (integrated signature classifier, ISC), used to stratify patients into classes of risk. This prediction reaches the 89.7% of sensitivity and 96.6% of specificity for the detection of PFS events. The prognostic value was then confirmed in the external independent validation set in which the PFS events are predicted with 75% sensitivity and 94.7% specificity. Moreover, the ISC shows higher classification performance than conventional clinical classifiers. Thus, the identified circuit enhances the understanding of the molecular mechanisms lagging behind stage I EOC and the ISC improves our capabilities to assess, at the time of diagnosis, the patient risk of relapse.
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Pilan N, Antoni V, De Lorenzi A, Chitarin G, Veltri P, Sartori E. A new deflection technique applied to an existing scheme of electrostatic accelerator for high energy neutral beam injection in fusion reactor devices. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B325. [PMID: 26932053 DOI: 10.1063/1.4939857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A scheme of a neutral beam injector (NBI), based on electrostatic acceleration and magneto-static deflection of negative ions, is proposed and analyzed in terms of feasibility and performance. The scheme is based on the deflection of a high energy (2 MeV) and high current (some tens of amperes) negative ion beam by a large magnetic deflector placed between the Beam Source (BS) and the neutralizer. This scheme has the potential of solving two key issues, which at present limit the applicability of a NBI to a fusion reactor: the maximum achievable acceleration voltage and the direct exposure of the BS to the flux of neutrons and radiation coming from the fusion reactor. In order to solve these two issues, a magnetic deflector is proposed to screen the BS from direct exposure to radiation and neutrons so that the voltage insulation between the electrostatic accelerator and the grounded vessel can be enhanced by using compressed SF6 instead of vacuum so that the negative ions can be accelerated at energies higher than 1 MeV. By solving the beam transport with different magnetic deflector properties, an optimum scheme has been found which is shown to be effective to guarantee both the steering effect and the beam aiming.
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Veltri P, Sartori E. Transmission of electrons inside the cryogenic pumps of ITER injector. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B313. [PMID: 26932041 DOI: 10.1063/1.4933187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Large cryogenic pumps are installed in the vessel of large neutral beam injectors (NBIs) used to heat the plasma in nuclear fusion experiments. The operation of such pumps can be compromised by the presence of stray secondary electrons that are generated along the beam path. In this paper, we present a numerical model to analyze the propagation of the electrons inside the pump. The aim of the study is to quantify the power load on the active pump elements, via evaluation of the transmission probabilities across the domain of the pump. These are obtained starting from large datasets of particle trajectories, obtained by numerical means. The transmission probability of the electrons across the domain is calculated for the NBI of the ITER and for its prototype Megavolt ITer Injector and Concept Advancement (MITICA) and the results are discussed.
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Zaupa M, Sartori E, Dalla Palma M, Fellin F, Marcuzzi D, Pavei M, Rizzolo A. Steady state thermal-hydraulic analyses of the MITICA cooling circuits. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B323. [PMID: 26932051 DOI: 10.1063/1.4936919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Megavolt ITER Injector Concept Advancement is the full scale prototype of the heating and current drive neutral beam injectors for ITER, to be built at Consorzio RFX (Padova). The engineering design of its components is challenging: the total heat loads they will be subjected to (expected between 2 and 19 MW), the high heat fluxes (up to 20 MW/m(2)), and the beam pulse duration up to 1 h, set demanding requirements for reliable active cooling circuits. In support of the design, the thermo-hydraulic behavior of each cooling circuit under steady state condition has been investigated by using one-dimensional models. The final results, obtained considering a number of optimizations for the cooling circuits, show that all the requirements in terms of flow rate, temperature, and pressure drop are properly fulfilled.
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Sartori E, Maceina TJ, Veltri P, Cavenago M, Serianni G. Simulation of space charge compensation in a multibeamlet negative ion beam. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B917. [PMID: 26932089 DOI: 10.1063/1.4933252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Ion beam space charge compensation occurs by cumulating in the beam potential well charges having opposite polarity, usually generated by collisional processes. In this paper we investigate the case of a H(-) ion beam drift, in a bi-dimensional approximation of the NIO1 (Negative Ion Optimization phase 1) negative ion source. H(-) beam ion transport and plasma formation are studied via particle-in-cell simulations. Differential cross sections are sampled to determine the velocity distribution of secondary particles generated by ionization of the residual gas (electrons and slow H2 (+) ions) or by stripping of the beam ions (electrons, H, and H(+)). The simulations include three beamlets of a horizontal section, so that multibeamlet space charge and secondary particle diffusion between separate generation regions are considered, and include a repeller grid biased at various potentials. Results show that after the beam space charge is effectively screened by the secondary plasma in about 3 μs (in agreement with theoretical expectations), a plasma grows across the beamlets with a characteristic time three times longer, and a slight overcompensation of the electric potential is verified as expected in the case of negative ions.
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Sartori E, Veltri P, Cavenago M, Serianni G. Background gas density and beam losses in NIO1 beam source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B118. [PMID: 26932000 DOI: 10.1063/1.4932976] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
NIO1 (Negative Ion Optimization 1) is a versatile ion source designed to study the physics of production and acceleration of H- beams up to 60 keV. In ion sources, the gas is steadily injected in the plasma source to sustain the discharge, while high vacuum is maintained by a dedicated pumping system located in the vessel. In this paper, the three dimensional gas flow in NIO1 is studied in the molecular flow regime by the Avocado code. The analysis of the gas density profile along the accelerator considers the influence of effective gas temperature in the source, of the gas temperature accommodation by collisions at walls, and of the gas particle mass. The calculated source and vessel pressures are compared with experimental measurements in NIO1 during steady gas injection.
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Spagnolo S, Spolaore M, Dalla Palma M, Pasqualotto R, Sartori E, Serianni G, Veltri P. Preliminary design of electrostatic sensors for MITICA beam line components. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B931. [PMID: 26932103 DOI: 10.1063/1.4935612] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Megavolt ITER Injector and Concept Advancement, the full-scale prototype of ITER neutral beam injector, is under construction in Italy. The device will generate deuterium negative ions, then accelerated and neutralized. The emerging beam, after removal of residual ions, will be dumped onto a calorimeter. The presence of plasma and its parameters will be monitored in the components of the beam-line, by means of specific electrostatic probes. Double probes, with the possibility to be configured as Langmuir probes and provide local ion density and electron temperature measurements, will be employed in the neutralizer and in the residual ion dump. Biased electrodes collecting secondary emission electrons will be installed in the calorimeter with the aim to provide a horizontal profile of the beam.
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Cavenago M, Serianni G, De Muri M, Agostinetti P, Antoni V, Baltador C, Barbisan M, Baseggio L, Bigi M, Cervaro V, Degli Agostini F, Fagotti E, Kulevoy T, Ippolito N, Laterza B, Minarello A, Maniero M, Pasqualotto R, Petrenko S, Poggi M, Ravarotto D, Recchia M, Sartori E, Sattin M, Sonato P, Taccogna F, Variale V, Veltri P, Zaniol B, Zanotto L, Zucchetti S. First experiments with the negative ion source NIO1. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B320. [PMID: 26932048 DOI: 10.1063/1.4932616] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Neutral Beam Injectors (NBIs), which need to be strongly optimized in the perspective of DEMO reactor, request a thorough understanding of the negative ion source used and of the multi-beamlet optics. A relatively compact radio frequency (rf) ion source, named NIO1 (Negative Ion Optimization 1), with 9 beam apertures for a total H(-) current of 130 mA, 60 kV acceleration voltage, was installed at Consorzio RFX, including a high voltage deck and an X-ray shield, to provide a test bench for source optimizations for activities in support to the ITER NBI test facility. NIO1 status and plasma experiments both with air and with hydrogen as filling gas are described. Transition from a weak plasma to an inductively coupled plasma is clearly evident for the former gas and may be triggered by rising the rf power (over 0.5 kW) at low pressure (equal or below 2 Pa). Transition in hydrogen plasma requires more rf power (over 1.5 kW).
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Veltri P, Antoni V, Agostinetti P, Brombin M, Ikeda K, Kisaki M, Nakano H, Sartori E, Serianni G, Takeiri Y, Tsumori K. Optics of the NIFS negative ion source test stand by infrared calorimetry and numerical modelling. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B908. [PMID: 26932080 DOI: 10.1063/1.4932982] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
At National Institute for Fusion Science (NIFS), a multi-ampere negative ion source is used to support the R&D on H(-) production, extraction, and acceleration. In this contribution, we study the characteristics of the acceleration system of this source, in order to characterize the beam optics at different operational conditions. A dedicated experimental campaign was carried out at NIFS, using as main diagnostic the infra-red imaging of the beam profiles. The experimental measurements are also compared with 3D numerical simulations, in order to validate the codes and to assess their degree of reliability. The simulations show a satisfactory agreement with the experimental results.
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Tsumori K, Ikeda K, Nakano H, Kisaki M, Geng S, Wada M, Sasaki K, Nishiyama S, Goto M, Serianni G, Agostinetti P, Sartori E, Brombin M, Veltri P, Wimmer C, Nagaoka K, Osakabe M, Takeiri Y, Kaneko O. Negative ion production and beam extraction processes in a large ion source (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B936. [PMID: 26932108 DOI: 10.1063/1.4938254] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Recent research results on negative-ion-rich plasmas in a large negative ion source have been reviewed. Spatial density and flow distributions of negative hydrogen ions (H(-)) and positive hydrogen ions together with those of electrons are investigated with a 4-pin probe and a photodetachment (PD) signal of a Langmuir probe. The PD signal is converted to local H(-) density from signal calibration to a scanning cavity ring down PD measurement. Introduction of Cs changes the slope of plasma potential local distribution depending upon the plasma grid bias. A higher electron density H2 plasma locally shields the bias potential and behaves like a metallic free electron gas. On the other hand, the bias and extraction electric fields penetrate in a Cs-seeded electronegative plasma even when the electron density is similar. Electrons are transported by the penetrated electric fields from the driver region along and across the filter and electron deflection magnetic fields. Plasma ions exhibited a completely different response against the penetration of electric fields.
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Serianni G, Agostinetti P, Antoni V, Baltador C, Cavenago M, Chitarin G, Marconato N, Pasqualotto R, Sartori E, Toigo V, Veltri P. Numerical simulations of the first operational conditions of the negative ion test facility SPIDER. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B927. [PMID: 26932099 DOI: 10.1063/1.4935209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In view of the realization of the negative ion beam injectors for ITER, a test facility, named SPIDER, is under construction in Padova (Italy) to study and optimize production and extraction of negative ions. The present paper is devoted to the analysis of the expected first operations of SPIDER in terms of single-beamlet and multiple-beamlet simulations of the hydrogen beam optics in various operational conditions. The effectiveness of the methods adopted to compensate for the magnetic deflection of the particles is also assessed. Indications for a sequence of the experimental activities are obtained.
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Sartori E, Brescaccin L, Serianni G. Simulation of diatomic gas-wall interaction and accommodation coefficients for negative ion sources and accelerators. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02A502. [PMID: 26931910 DOI: 10.1063/1.4932975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Particle-wall interactions determine in different ways the operating conditions of plasma sources, ion accelerators, and beams operating in vacuum. For instance, a contribution to gas heating is given by ion neutralization at walls; beam losses and stray particle production-detrimental for high current negative ion systems such as beam sources for fusion-are caused by collisional processes with residual gas, with the gas density profile that is determined by the scattering of neutral particles at the walls. This paper shows that Molecular Dynamics (MD) studies at the nano-scale can provide accommodation parameters for gas-wall interactions, such as the momentum accommodation coefficient and energy accommodation coefficient: in non-isothermal flows (such as the neutral gas in the accelerator, coming from the plasma source), these affect the gas density gradients and influence efficiency and losses in particular of negative ion accelerators. For ideal surfaces, the computation also provides the angular distribution of scattered particles. Classical MD method has been applied to the case of diatomic hydrogen molecules. Single collision events, against a frozen wall or a fully thermal lattice, have been simulated by using probe molecules. Different modelling approximations are compared.
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