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Beam-profile indicator for 184-inch cyclotronBrown, Robert L. January 1959 (has links)
Thesis (M.S. in Physics)--United States Naval Postgraduate School, 1959. / "Physics and Mathematics" -t.p. Includes bibliographical references (p. 17).
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Estudo da difusao de helio implantado em ciclotron nos metais de estrutura de face centrada Au, Ag e AlSCIANI, VALDIR 09 October 2014 (has links)
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The design and development of a microprocessor based control system for an electric rail transport systemHuman, TM January 1988 (has links)
Thesis (Masters Diploma (Technology) Cape Technikon, 1988 / Radioactivity and radioactive radiation are two scientific phenomena which man has always approached with great caution, if not fear. Radioactive radiation cannot be sensed by any of the human senses and experience has proved just how hazardous it can be to the human body. This caution is therefore by no means unfounded and through the years a set of standards has been derived as to what can be regarded as a safe dose to the human body. At the National Accelerator Centre radioisotopes are being produced by a chemical recovery process from targets which have been irradiated by a high energy proton beam. Targets are prepared by compressing salts, containing the elements to become radioisotopes, into tablets. The high energy protons collide with particles in the targets which give off radioactive radiation. The targets in their turn become radioactive and the isotopes that are produced from these targets are radioactive. The level of radioactive radiation is extremely hazardous and it is therefore impossible for any human being to come into close contact with any of the targets or isotopes. It is for these reasons that an electrical rail transport system was installed at the National Accelerator Centre to transport highly radioactive sources. The transport system links the two irradiation vaults to the two rows of hot cells, where the chemical recovery takes place, and to a well shielded storage area for storage of isotopes and radioactive waste. A transport system, performing tasks of this nature, must be, above all, extremely reliable. Secondly, commands entered by an operator to control the system, must be simple and straight forward. This thesis describes the control of the transport system at the National Accelerator Centre, including alI of its features, advantages and disadvantages.
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Estudo da difusao de helio implantado em ciclotron nos metais de estrutura de face centrada Au, Ag e AlSCIANI, VALDIR 09 October 2014 (has links)
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The cyclotron production of selected radionuclides using medium energy protonsVan der Meulen, N. P. (Nicolas Philip) 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: Radiochemical research involving ion exchange chromatography is of paramount
importance to the future of radionuclide production at the Radionuclide Production
Group (RPG) of iThemba LABS. It is required for the production of high-activity
yields of radionuclides to effectively remove impurities and for the safety of the
operators performing such productions. The radiochemical separations of some new
products from their target material, as well as experiments to determine whether
production is viable, are described.
67Ga is currently being produced at the RPG and makes use of zinc targets. With the
production of ultra-pure 67Ga, it was necessary to remove any Fe(III) impurities from
the final product, such that it may be possible to label peptides with this product. The
use of Amberchrom CG161M for this purpose was found to be satisfactory.
Interest was shown in 88Y by an overseas company for the manufacture of sources.
While a method involving extraction of the radionuclide and the ion exchange thereof
using Chelex 100 chelating resin had been published, problems with the production
persisted. Three methods, using ion exchange chromatography, were devised to
produce the radionuclide, with two of them being adopted for production purposes.
Thick-target nuclear data have also recently been accumulated in collaboration with
colleagues from ATOMKI, Debrecen, Hungary.
There is a large demand for 82Sr for the manufacture of 82Sr/82Rb generators for
medical use. A method was developed to manufacture this radionuclide with thicker
(32 g) target material, bombarded in the Vertical Beam Target Station (VBTS), and to
separate 82Sr from its target material with the use of Purolite S950 chelating resin.
68Ge/68Ga generators are becoming increasingly important in the world of
radiopharmaceuticals. A project to develop a local generator was funded by the
Innovation Fund and research was performed to produce 68Ge, such that the generator
could be manufactured. This involved bombarding thicker Ga targets in the VBTS
and performing the chemical separation using AG MP-1 anion exchange resin. The final product was loaded onto generators, although tests performed on different
materials to the ones being marketed are also reported in this work.
A project was initiated to study the cluster radioactive decay of 223Ac via 14C and 15N
emission. To produce 223Ac for these observations, a Th target was bombarded. The
227Pa was separated from the target material using AG MP-1 macroporous anion
exchange resin and used as a source, which decayed to 223Ac. The chemical
separation and the drying of the final product onto a source plate were completed
within approximately 70 minutes from the end of bombardment. The work was
performed in collaboration with JINR, Russia, and University of Milan and INFN,
Italy.
133Ba has a half-life of over 10 years and is an expensive radionuclide to produce. It
has been used in medical and biological studies and there still appears to be a demand
for it. A method was devised, utilizing AG50W-X4 cation exchange resin, to separate
133Ba from its CsCl target material.
Agricultural specialists in the past have shown an interest in 28Mg, to determine the
uptake of the element in fruit. It has long been regarded by some of the local
researchers as an interesting project to investigate. It has been determined that the
product can be produced in reasonable quantities using LiCl target material, with ten
targets being bombarded in series using a 200 MeV proton beam delivered by the
Separated Sector Cyclotron. A method, involving the use of Purolite S950 chelating
resin, was devised to separate 28Mg from its target material. / AFRIKAANSE OPSOMMING: Radiochemiese navorsing, wat ioonuitruiling chromatografie behels, is van uiterste
belang vir die toekoms van die produksie van radionukliede by die
Radionukliedproduksiegroep (RPG) van iThemba LABS. Dit is nodig vir die hoë
aktiwiteit opbrengs van radionuklied produkte om onsuiwerhede te verwyder en vir
die veiligheid van die operateurs wat die produksies moet uitvoer. Die skeiding van
nuwe produkte van hulle skyfmateriaal, sowel as eksperimente om vas te stel of ‘n
produksie uitvoerbaar is, word in die werk beskryf.
67Ga word tans by RPG vervaardig en maak gebruik van sink as skyfmateriaal. Vir
die produksie van “ultra-suiwer” 67Ga was dit belangrik om enige Fe(III)
onsuiwerhede uit die finale produk te verwyder om sodoende peptiede merking te kan
uitvoer. Die gebruik van Amberchrom CG161M hars was voldoende vir dié
eksperiment.
‘n Oorsese maatskappy het belangstelling getoon in 88Y vir die vervaardiging van
bronne. Alhoewel ‘n metode wat die ekstraksie van die radionuklied en die ioonuitruiling
daarvan met die gebruik van Chelex 100 chelerende hars reeds gepubliseer
was, het probleme met die produksie voortgeduur. Drie metodes is opgestel om 88Y te
produseer, waarvan twee van die metodes tans gebruik word vir produksie doeleindes.
Dik-skyf kerndata is ook versamel in samewerking met kollegas van ATOMKI,
Debrecen, Hongarye.
Daar is ‘n groot aanvraag vir 82Sr vir die vervaardiging van 82Sr/82Rb generators vir
mediese doeleindes. ‘n Metode is ontwikkel om die radionuklied te vervaardig van
dikker skyfmateriaal (32 g), in die Vertikale Bundelstasie gebombardeer, en om 82Sr
van sy skyfmateriaal te skei met die gebruik van Purolite S950 chelerende hars.
68Ge/68Ga generators is besig om toenemend belangrik te word in die wêreld van
radiofarmasie. iThemba LABS kry baie navrae om die produk te vervaardig. Die
projek was ook deel van die voorlegging aan die “Innovation Fund” en ‘n manier is
ondersoek om 68Ge te vervaardig, wat benodig word om so ‘n generator te laai. Dik Ga skyfmateriaal word in die Vertikale Bundelstasie gebombardeer en ‘n chemiese
skeiding is uitgevoer deur gebruik te maak van AG MP-1 anioonuitruiling hars. Die
finale produk is op die generators gelaai vir toetsdoeleindes. Toetse is ook op ‘n ander
tipe generator uitgevoer en word in die werk beskryf.
‘n Projek is begin om “cluster” radioaktiewe verval van 223Ac, via 14C en 15N emissie,
te bestudeer. ‘n Th-skyf is met protone gebombardeer om die 223Ac te produseer vir
die eksperiment. 227Pa is vervaardig en geskei van die skyfmateriaal. Dit is gedoen
met die gebruik van AG MP-1 makroporeuse anioonuitruiling hars en drooggemaak
op ‘n bronplaat, waar dit verval het na 223Ac. Die chemiese skeiding en die
droogmaak van die finale produk op ‘n bronplaat is uitgevoer binne 70 minute na
Einde van Bombardering (EVB). Die werk is deel van ‘n samewerking met kollegas
van JINR, Rusland, en die Universiteit van Milaan, sowel as INFN, Italië.
133Ba het ‘n halveertyd van oor die tien jaar en is ‘n duur produk om te vervaardig.
Dit is al gebruik in mediese en biologiese studies en daar is deesdae ‘n redelike
aanvraag daarvoor. ‘n Metode is uitgewerk om 133Ba te skei van die CsCl
skyfmateriaal met die gebruik van AG50W-X4 katioonuitruiling hars.
Spesialiste in landboustudies het in die verlede belangstelling getoon in 28Mg. Dit
word gebruik om die absorpsie van dié element in vrugte te ondersoek. Die produk
kan vervaardig word met die gebruik van LiCl skyfmateriaal: tot soveel as tien skywe
(agter mekaar) word gebombardeer met ‘n 200 MeV protonbundel te iThemba LABS.
‘n Metode, wat Purolite S950 behels, is daargestel om 28Mg van die skyfmateriaal te
skei.
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The study of a novel flat-topping resonator for more intense proton beams of better quality from cyclotronsDe Villiers, John Garrett 20 January 2009 (has links)
ABSTRACT
The multi-disciplinary accelerator based facilities at iThemba LABS are used intensively for
nuclear physics experiments, radiotherapy and the production of radioisotopes. To increase the
beam intensity for radioisotope production and to improve the beam quality of the 66 MeV
proton beam, a double-gap horizontal half-wave flat-topping resonator has been developed for
the separated-sector cyclotron to operate at the associated fixed frequency. This type of flattopping
resonator has never before been implemented in a cyclotron and this study is the first
to show that it can be done, featuring a special characteristic not offered by other types. The
resonator is reviewed against the other types of resonators that are already in use at other
institutes around the world.
The flat-topping voltage of the selected type has a sinusoidal half-wave distribution along a
radial line in each of its acceleration gaps with the nodal points located on the injection and
extraction orbits. The flat-topping voltage therefore progressively increases from zero at both
of the two most critical orbits in a cyclotron to a maximum at about halfway between them. As
a result will this resonator, apart from its basic function to reduce the energy spread in the
beam, not decrease the orbit separation at the injection and extraction orbits in the cyclotron,
as is the case with other types of flat-topping resonators. This advantageous feature implies
that the beam pattern in the cyclotron is not affected in the regions of the delicate injection and
extraction components and therefore will these components or the operational control of the
beam not require any modification to accommodate the resonator.
In order to design a resonator that will meet our requirements, the theory of the beam
dynamics and resonator characteristics were studied to ascertain the expected improvement in
beam quality and beam intensity when a flat-topping resonator is implemented with the
cyclotron. All resonator types were considered and studied in terms of their power dissipation,
voltage distribution, harmonic number, space requirements and influence on the beam. The
horizontal half-wave resonator type, with two acceleration gaps, was selected as the most
suitable for our application, because of its preferred electromagnetic characteristics and its
geometric shape that permits the installation inside an existing vacuum chamber through an
existing flange. Initially a half-scale resonator model was build to test the feasibility of such a
resonator and also to verify the calculation methods.
Transmission line methods and numerical field analysis in 3D were applied to determine the
resonator characteristics. In the former method a computer program, POISSON, was used to
calculate curvilinear squares on sections through a triangular-shaped transmission line and in
the latter method a commercial computer program, SOPRANO, was used. SOPRANO is part
of an internationally acclaimed suite of programs and the acquired knowledge and skill to use
this state-of-the-art software for the studying and designing of such and other electromagnetic
devices also put the institute amongst the front-runners in the world.
The calculated characteristics of the half- and full-scale resonator models, the study of the
different electromagnetic modes that resonate in close proximity to the required frequency, the
heat transport modelling and the theory and implementation of the coupling and tuning
devices are all in good agreement with their respective measured results and are reported in
this document.
This study lead the way to have the first-ever double-gap horizontal half-wave flat-topping
resonator in a cyclotron successfully commissioned at iThemba LABS and the first tests with
beam report very stable operation. Accelerator physicists now have another option to utilize for the establishing of flat-topped acceleration voltages.
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The activation of stable isotopes, their migration in soil and groundwater at a radionuclide production facility : a case study in Faure, Cape Town, South AfricaMarazula, Thandazile January 2018 (has links)
Thesis (MTech (Environmental Management))--Cape Peninsula University of Technology, 2018. / The iThemba Laboratory for Accelerator Based Sciences (iThemba LABS or iTL), a facility governed by the National Research Foundation (NRF) based in Cape Town has embarked on a project called the South African Isotope Facility (SAIF). Part of the SAIF will be a project called the Low Energy Radioactive Ion Beam (LERIB) for the production of radioactive beams with the Separated Sector Cyclotron (SSC). The LERIB project is anticipated to generate significant prompt sources of ionising radiation such as neutrons displaced by protons during bombardment of targets. At present, the facility has 3 - 5 m thick concrete walls designed to shield against 200 MeV neutrons. The floor thickness varies from each vault according to the behaviour and characteristics of the produced radiation. The LERIB facility concrete floor is envisioned to be 1 m thick. Insufficient floor shielding might expose the sub-surface strata below the floor with ionising radiation. Some matter in the exposed strata might undergo activation and consequently produce undesirable radioactive isotopes. Exposure to radioactive isotopes can pose potential risks to the general public and the receiving environment. In the sub-surface, the activated isotopes can spread through the soil and groundwater bodies. Groundwater being mobile in nature might act as conduit for activated isotopes to migrate in the subsurface. The half-lives of the formed radionuclides were used to estimate the distance the radionuclides can migrate in the sub-surface before decay. The X-Ray Fluorescence (XRF) and Inductive Coupled Plasma - Mass Spectrometry (ICP-MS) were used to quantify the mass fraction of elements from soil and groundwater samples. The Inductive Coupled Plasma - Optical Emission Spectrometry (ICP-OES) was used to measure dissolved metals of major and minor oxides in groundwater samples. These scientific techniques were applied in order to measure mass fractions of elements present in the sub-surface anticipated to be exposed with neutron radiation. Results revealed that the sub-surface in the study site constitutes Si, Al, Na and Fe in abundance. This suggests that, these elements might have a high probability to undergo activation compared to those occurring at lower concentrations, such as minor and trace elements. However the neutron capture cross-section for these elements varies and hence some elements such as Si and Al were not activated. To investigate elements measured from the ICP-MS, ICP-OES and XRF which might undergo activation, soil and water samples were irradiated for an hour with neutrons from a Beryllium target from a range of 0 – 66 MeV energy. The results revealed that activating the sub-surface with neutron radiation will result to the formation of short and long-lived unstable isotopes. However, isotopes with long half-lives such as 22Na, 52Mn, 54Mn and 46Sc only occurred in soil samples and none measured from the water samples except a short-lived isotope 24Na. These results agrees with the reviewed literature that, water being a product of two hydrogens and one oxygen, with 1H from H2O considered to be a good neutron moderator should have absorbed the neutrons so as to reduce neutron capture cross-sections.
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Desenvolvimento de novo metodo de producao de sup(111)In a partir da irradiacao de Cd com protonsLION, LUCIANA F. de 09 October 2014 (has links)
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Medidas de desgaste em aco inoxidavel AISI 316 por meio de ativacao superficial em ciclotronSUMIYA, LUIZ C. do A. 09 October 2014 (has links)
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Modelos analiticos para o desenvolvimento de alvos metalicos de alta performance irradiados nos ciclotrons cyclone 30 e cyclone 18 do IPEN-CNEN/SP / Analytical models for development of high performance metal targets irradiated in IPEN-CNEN/SP cyclone 30 and cyclone 18 cyclotronsOLIVEIRA, HENRIQUE B. de 09 October 2014 (has links)
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