Separation technique of rhenium radioisotopes from a deuteron-irradiated tungsten target of natural isotopic composition has been developed. The irradiated tungsten powder was dissolved in a mixture ...of H
2
O
2
and NaOH, the solution was passed through a column filled with an extraction chromatographic sorbent TEVA Resin. Rhenium was eluted with 4 M nitric acid. The separation procedure takes approximately 3 h, the radiochemical yield of rhenium is more than 97%.
The efficiency of employing a beam of intermediate-energy
He particles for the production of the radionuclide
Pa on natural-thorium targets, which is used to obtain a
U therapeutic
emitter was ...estimated. The cross section for the reaction
Pa and the cross sections for the accompanying reactions
Pa and
Pa in the energy range from 39 to 58 MeV were measured. Experimental results were compared with theoretical data from TENDL-2019 library. The present experiment did not confirm a large cross-section values presented in TENDL-2019 library (up to 400 mb for the reaction
Pa). Therefore, this reaction can hardly be viewed as an alternative to proton- and deuteron-induced reactions for production of
Pa. The cross sections for the reactions
Pa and
Pa in TENDL-2019 also differ significantly from the experimental data.
Modular nanotransporters (MNTs) are promising technology for nuclear medicine of the present time which is based on an engineered polypeptide platform. Emitters of Auger electrons can be used in pair ...with MNTs as short-range cytotoxic agents, and among the most effective ones
Rh with parent nuclide of
Ru (
min and
d respectively) is to be noted. This work provides new experimental data of cumulative yield of
Ru radionuclide for
He-,
He-, proton- and deuteron-induced reactions on ‘‘thick’’ ThO
targets. Data shows that acquired activity of
Ru is sufficient for creation of
Ru/
Rh generator.
Abstract
Method for production of alpha emitter
149
Tb by irradiation of
151
Eu with 70 MeV
3
He nuclei is proposed. For the first time, the cross sections for the formation of isotopes
...149,150,151,152
Tb were measured experimentally using a stack foil technique in the
3
He particles energy range 70 → 12 MeV. The thick target yield of
149
Tb is 39 MBq/μAh, or 230 MBq/μA
149
Tb at saturation. The optimal energy range from the point of view of radioisotopic purity is 70 → 40 MeV. At these conditions about 150 MBq/μA
149
Tb can be produced in 8 hours irradiation, which is sufficient for therapeutic applications. The main impurities are
150
Tb (~100% in activity) and
151
Tb (~30% in activity). The proposed method surpasses its counterparts by the high content of the target isotope in the natural mixture and the simplicity of the radiochemical separation of
149
Tb from the bulk target material.
An experimental complex was created at the NRC Kurchatov Institute for testing of structural materials developed for MSR. The complex makes it possible to implant helium and (or) hydrogen into ...material specimens at the U-150 cyclotron, simulating the result of long-term neutron exposure, to perform mechanical tests and microstructural studies before and after simulation exposure, and to test the compatibility of structural materials before and after exposure with fuel salt in non-isothermal dynamic conditions at temperatures up to 750°C with control of the melt redox potential. Preliminary tests with samples of nickel-molybdenum alloy KhN80MT demonstrated the efficiency of the proposed experimental technique. The concentration of helium nuclei in the alloy samples reaches ~150 ppm for approximately 10 h of irradiation.
—
One of the methods for obtaining
123
I is the bombardment of gaseous
124
Xe with protons, in which nuclear reactions of production and decay of
123
Xe and
123
I isotopes occur. After irradiation, ...the gas phase is condensed from the target into a special “decay container,” in which the target isotope
123
I is produced and accumulated during
123
Xe decay. The amount of
123
I produced in the target and deposited on its walls during the irradiation is comparable to the amount of
123
I obtained in the decay container. A laboratory setup has been created and a process technology for extracting
123
I from the walls of the target has been developed to increase the total yield of
123
I. Organic solvents (acetone and diethyl ether) are used for this purpose. The proportion of the
123
I extracted by washing off from the walls of the aluminum target is at least 84%. The loss during subsequent vacuum distillation of solvents does not exceed 5%. After vacuum distillation, the extracted
123
I is dissolved in NaOH. At this stage, the efficiency of
123
I washing-off with a 0.01 M NaOH solution is at least 95%. Nevertheless, even taking into account these losses, the proposed method makes it possible to additionally extract the
123
I radionuclide from the target in an amount equal to or greater than the activity of the
123
I produced using the existing technology.
Two rhenium isotopes (
186
Re and
188
Re) are of interest for nuclear medicine. The multiplicity of oxidation states and varying coordination chemistry of rhenium provide opportunities for the ...synthesis of various bioconjugates, including those based on nanosized carriers (liposomes, dendrimers, and inorganic nanoparticles). This review analyzes nuclear reactions that lead to the formation of rhenium isotopes and methods of their isolation from targets, as well as different variants of the application of rhenium in nuclear medicine.
At present, the radioisotope
U is considered as one of the most promising
-emitters for application in immunotherapy. In order to refine nuclear data and to evaluate the efficiency of
U production, ...the cross sections for the reactions
Th(
He,
)
U and
Th(
He,
)
U, as well as the cross sections for the accompanying reactions
Th(
He,
)
Pa and
Th(
He,
)
Pa, were measured for the first time in the range of energies of
He nuclei between 30 and 62 MeV. The activation technique was used to measure the reaction cross sections. The experimental cross sections were compared with data from the TENDL-2021 library. The results give grounds to conclude that the reactions
Th(
He,
)
U and
Th(
He,
)
U cannot ensure efficient production of
U at the U-150 cyclotron of National Research Center Kurchatov Institute. Therefore, they cannot be viewed as an alternative to proton- and deuteron-induced reactions producing
U.
The cross sections of the reactions
186
W(
4
He, p3n)
186
Re,
186
W(
4
He, pn)
188
Re, and
186
W(
4
He, p)
189
Re were measured by the activation method in the energy range of 4He nuclei 24–63 MeV. ...For all three reactions the cross sections in the TENDL-2019 nuclear data library differ from experiment by more than a factor of 2 in a wide energy range.
An apparatus for the rapid thermal extraction of Re radioisotopes from an irradiated tungsten target has been developed. Its operation was tested using a tungsten target pre-irradiated with deuterons ...on the U-150 cyclotron of the Kurchatov Institute. A description of the design of the apparatus and the principle of its operation are given. It has been shown that in one two-stage calcination–sublimation cycle, at least 89% of the Re activity from the W target can be collected on the receiving area of the collector. The apparatus can be used to isolate the
186
Re isotope formed from
186
W upon irradiation with protons or deuterons of cyclotron targets.
PDF
