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The GRAND universal gas-filled separator, located at the Factory of Super-Heavy Elements in the Flerov Laboratory of Nuclear Reactions (FLNR), Joint Institute for Nuclear Research, has been created and put into operation. The separator can be used both in experiments on α, β, and γ spectroscopy of isotopes of heavy and superheavy elements and in experiments on the chemical properties of superheavy elements as a preseparator. The results of the first experimental tests of the GRAND separator are presented. The possibility of effectively carrying out experiments both on a "physical" detection system and on a "chemical" installation has been demonstrated. [ABSTRACT FROM AUTHOR]

Among nuclides, Pt isomer is characterized by a number of properties that make it suitable for use in nuclear medicine. Effective ways of optimizing the Pt isomer yield at low impurity contents must be sought. The method based on double neutron capture by the Ir target nucleus with subsequent populating of Pt through β decay allows chemical isolation of the isomer. In this work, the problem is analyzed, test experiments on Ir activation with neutrons are conducted, and theoretical estimates of the Pt yield are presented. Full-scale model experiments on the IBR-2 reactor in Dubna should confirm the effectiveness of the method. [ABSTRACT FROM AUTHOR]

We have determined the total bremsstrahlung photon fluxes with end-point energies in the giant dipole resonance (GDR) region produced by electron accelerator Microtron MT-25 (the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia) and that of 65 MeV bremsstrahlung produced by the linear electron accelerator (the Pohang Neutron Facility, Pohang, South Korea). The method that we used was the photon activation technique. To ensure the accuracy of the results, we carried out simultaneous photon activation of two monitors made of Cu and Au foils in the same irradiation conditions. The results are discussed in the paper. [ABSTRACT FROM AUTHOR]

Isocratic anion exchange separations of Group V elements from solutions containing HF have been considered for the development of Db aqueous phase chemistry experiments. Separation of Nb/Ta from an HF/NHF system has been demonstrated but has limited utility due to interferences with alpha and spontaneous fission (SF) source preparation. The physical parameters associated with ion exchange chromatography have been optimized for the separation and sequential isolation of Pa, Nb and Ta from mixed HF/HNO solutions. A suitable procedure incorporating a series of successive chemical separation techniques, i.e. precipitation and ion exchange chromatography, has been suggested for off-line Db characterization studies. [ABSTRACT FROM AUTHOR]

Irradiation of natural lutetium oxide target with 7Li beam results in the formation of no-carrier-added 177W radionuclide in the matrix. An efficient radiochemical procedure for the separation of no-carrier-added (nca) 177W ( T1/2 = 2.21 h) radionuclide is presented using liquid-liquid extraction (LLX). A high separation factor between nca 177W from the target Lu has been achieved with 0.1 M TOA and 8 M HCl. About 85% of 177W has been extracted in the organic phase keeping Lu in the aqueous phase in a single run. Using this production and separation method radiochemically pure 177W can be obtained. The separation has also been tried with a greener approach viz. aqueous biphasic extraction. In this case, aqueous biphasic extraction is not a good method for separation of 177W. The radionuclide 177W thus obtained can be used to study the extraction pattern of lighter homologue of the element 106 (Sg) together with Mo, which in turn is important to investigate the chemistry of Sg. [ABSTRACT FROM AUTHOR]

A procedure was developed for selective separation of Group IV elements from Sr and Lu, followed by rapid separation of Zr and Hf by cation-exchange chromatography in dilute HCl/HF solutions. The possibility of using this procedure for chemical identification and determination of decay parameters of the new isotope 267Rf was demonstrated. [ABSTRACT FROM AUTHOR]

A 111In → 111 mCd radionuclide generator with the chemical yield higher than 95% and content of parent isotope (1 1 1In) in the 1 1 1 mCd preparation less then 0.6% (relative to the activity of the target nuclide) was developed. Parent and daughter radionuclides were separated by extraction chromatography using di-2-ethylhexyl hydrogen phosphate. The probability of electron capture to the 396-keV isomeric state (1 1 1 mCd) in 1 1 1In decay is (6.01±0.14r a n d o m±0.18s y s)×10- 5. [ABSTRACT FROM AUTHOR]

A short review of the radiochemical methods for preparation of widely used or promising cyclotronproduced radionuclides for nuclear medicine and biomedical or environmental studies is given. The presented data include the current status of the production of some gamma-emitters (97Ru, 111In, 123I, 201Tl), generator-pairs (68Ge/68Ga, 82Sr/82Rb, 128Ba/128Cs, 178W/178Ta), radioisotopes for metabolism studies (26Al, 67Cu, 237Pu) and actinides tracers for environmental researches (235Np, 236Np, 236Pu). The conditions for preparation of high-purity isotopes have been investigated and procedures including target chemistry design were developed. [ABSTRACT FROM AUTHOR]

Among radioactive isotopes of rare-earth elements (REEs) finding increasing application in nuclear medicine, α-emitting 149Tb ( T1/2 = 4.118 h; EC 76.2%; β+ 7.1%; α 16.7%) shows promise for radioimmumotherapy. Formation of 149Tb in nuclear reactions Nd(12C, xn)149Dy(4.23 min; β+, EC) → 149Tb performed by irradiation of a Nd target with carbon ions was experimentally studied. As estimated from the experimental data on 149Dy formation and its decay into 149Tb, the 149Tb yield under the best conditions (142Nd-enriched target, 12C ions with the energy of up to 120 MeV and current of up to 100 μA, irradiation time 8-10 h) can be as high as 30 GBq (0.8 Ci). [ABSTRACT FROM AUTHOR]

The flux weighted average cross sections and the isomeric yield ratios of 110m, gIn, 111m, gIn and 112m, gIn in the natIn(γ,xn) 112-110In reactions with the bremsstrahlung end-point energies of 65, 70 and 75 MeV have been determined by activation and off-line γ-ray spectrometric technique using the 100 MeV electron linac at Pohang accelerator laboratory, Korea. It was found that the natIn(γ,xn) 112-110In reaction cross sections increase very fast from the threshold energy to a certain value of the bremsstrahlung energy, where the other reaction channel opens. After a certain energy, it remains constant because the cross section of the other reaction channel starts to increase. This indicates the partition of the excitation energy in different reaction channles. The isomeric yield ratios of 110m, gIn, 111m, gIn and 112m, gIn in the natIn(γ,xn) reactions decrease very fast with the bemsstrahlung end-point energy from the threshold value to 15-30 MeV due to the giant dipole resonance (GDR) effect. Above that, the isomeric yield ratios increase slowly with the bremsstrahlung energy due to the increase of excitation energy. [ABSTRACT FROM AUTHOR]