Uranium carbide dispersed in graphite was produced under vacuum by means of carbothermic reduction of different uranium oxides (UO
2, U
3O
8 and UO
3), using graphite as the source of carbon. The ...thermal process was monitored by mass spectrometry and the gas evolution confirmed the reduction of the U
3O
8 and UO
3 oxides to UO
2 before the carbothermic reaction, that started to occur at
T
>
1000
°C. XRD analysis confirmed the formation of α-UC
2 and of a minor amount of UC. The morphology of the produced uranium carbide was not affected by the oxides employed as the source of uranium.
Status of the SPES Exotic Beam Facility Comunian, M; Andrighetto, A; Antonini, P ...
Journal of physics. Conference series,
01/2020, Letnik:
1401, Številka:
1
Journal Article
Recenzirano
Odprti dostop
At Legnaro National Laboratories of INFN is under construction a Rare Isotope Facility called "Selective Production of Exotic Species" (SPES) based on a 35-70 MeV proton cyclotron, able to deliver ...two beams with a total current up to 0.75 mA, an ISOL fission target station and an existing ALPI superconducting accelerator as a post accelerator (up to 10 MeV/u for A/q=7). The paper will cover notably: the high-resolution mass separator, the CW RFQ (80 MHz, 727 keV/u, with internal bunching), the 1+ low energy transfer line and the injection line from Charge Breeder to ALPI under installation.
SPES (Selective Production of Exotic Species) is an ISOL type facility for production and post-acceleration of exotic nuclei for forefront research in nuclear physics. Radioactive (RA) species (A = ...80÷160) will be produced by fissions induced by a proton beam impinging on an UCx target: the proton beam will be delivered by a commercial cyclotron with a 40 MeV maximum energy and a 0.25 mA maximum current. The RA species, extracted from the Target-Ion-Source system as a 1+ beam, will be cooled in a RFQ (radiofrequency quadrupole) beam cooler (RFQ-BC) and purified from the isobars contaminants through a High Resolution Mass Separator (HRMS). Post-acceleration will be performed via an ECR-based charge breeder, delivering the obtained q+ RA beam to a being built CW RFQ and to the being upgraded superconducting (sc) linac ALPI (up to 10 MeV/A for a mass-to-charge ratio A/q = 7).
The SPES Radioactive Ion Beam (RIB) facility at INFN-LNL is in the construction phase. It is based on the ISOL method with an UCx Direct Target able to sustain a power of 10 kW. The primary proton ...beam is delivered by a high current Cyclotron accelerator, with energy 35-70 MeV and a beam current of 0.2-0.5 mA. Neutron-rich radioactive ions will be produced by proton induced Uranium fission in the UCx target at an expected fission rate in the order of 10 super(13) fissions per second. The exotic isotopes will be re-accelerated by the ALPI superconducting LINAC at energies of 10A MeV and higher, for masses in the region A=130 amu at expected rate on the secondary target of 10 super(7) - 10 super(9) pps. The SPES project has the aim to provide high intensity and high-quality beams of neutron-rich nuclei as well as to develop an interdisciplinary research center based on the cyclotron proton beam.
In the framework of the SPES project at LNL-INFN a method for emissivity measurements by a double-frequency pyrometer in the infrared region at high temperatures on opaque gray bodies of SiC and ...graphite is presented. The measurement method proposed in this work reveals a good fitting with literature values. Moreover, the effect of surface finishing on emissivity values has been investigated.
The ISOLPHARM project explores the feasibility of exploiting an innovative technology to produce extremely high specific activity beta-emitting radionuclides as radiopharmaceutical precursors. This ...technique is expected to produce radiopharmaceuticals that are virtually mainly impossible to obtain in standard production facilities, at lower cost and with less environmental impact than traditional techniques. The groundbreaking ISOLPHARM method investigated in this project has been granted an international patent (INFN). As a component of the SPES (Selective Production of Exotic Species) project at the Istituto Nazionale di Fisica Nucleare–Laboratori Nazionali di Legnaro (INFN–LNL), a new facility will produce radioactive ion beams of neutron-rich nuclei with high purity and a mass range of 80–160 amu. The radioactive isotopes will result from nuclear reactions induced by accelerating 40 MeV protons in a cyclotron to collide on a target of UC
x
. The uranium in the target material will be
238
U, yielding radioactive isotopes that belong to elements with an atomic number between 28 and 57. Isotope separation on line (ISOL) is adopted in the ISOLPHARM project to obtain pure isobaric beams for radiopharmaceutical applications, with no isotopic contaminations in the beam or subsequent trapping substrate. Isobaric contaminations may potentially affect radiochemical and radionuclide purity, but proper methods to separate chemically different elements can be developed.
Mesoporous lanthanum carbide–carbon nanotube composites were produced by means of carbothermal reaction of lanthanum oxide, graphite and multi-walled carbon nanotube mixtures under high vacuum. ...Residual gas analysis revealed the higher reactivity of lanthanum oxide towards carbon nanotubes compared to graphite. After sintering, the composites revealed a specific surface area increasing with the amount of carbon nanotubes introduced. The meso-porosity of carbon nanotubes was maintained after thermal treatment.
Porous lanthanum carbide (LaC
2) based materials were prepared from lanthanum oxalate (La
2(C
2O
4)
3), lanthanum oxide (La
2O
3) and graphite mixtures. The molar ratio between La
2O
3 and La
2(C
2O
...4)
3 was varied in order to detect the effect of starting mixtures on the porosity of the products. Samples structure and morphology were investigated by means of scanning electron microscopy, equipped with the probe for elemental analysis, (SEM-EDS) and X-ray diffraction spectrometry (XRD). As for the porosity characterization, the amount of total porosity was derived from the comparison between the theoretical and the measured density values, whereas a thorough investigation on the amount of open porosity and pore size distribution was carried out by means of Mercury Intrusion Porosimetry, after carburization and sintering. Emissivity measurements were performed upon carburization and sintering in order to verify the effect of porosity on emissivity values.
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