[en] Technetium-99 is a long-lived fission product with a half-life of about 2.1 x 10⁵ years, which decays by β-emission. For the transmutation of ⁹⁹Tc, research on solid technetium was started. Technetium metal powder purchased was analyzed by X-ray diffraction, γ-ray spectrometry, and inductively coupled plasma-atomic emission spectrometry and -mass spectrometry. The lattice parameters obtained were agreed with the reported values. The metallic impurity was about 15 ppm, where aluminum and iron contributed mainly. No impurity nuclide with γ-emission was found. Using the technetium metal powder, button-, rod-, and disk-shaped samples of technetium metal were prepared by arc-melting technique. Thermal diffusivity of technetium metal was measured on a disk sample from room temperature to 1173 K by laser flash method. The thermal diffusivity decreased with increasing temperature though it was almost constant above 600 K. (author)

[en] Radiopharmaceutical preparations of relatively long-lived radionuclides (with half-lives ranging from few days to few months) are available from many commercial suppliers; in addition, national atomic energy organisations in many countries have undertaken reprograms for their production and supply to meet the national needs. ⁹⁹Tc^m is available in the form of generators which consist of the parent ⁹⁹Mo retained on a column of alumina from which the ⁹⁹Tc^m is eluted out with normal saline. Other generator systems which enable the separation of the daughter ⁹⁹Tc^m from the parent ⁹⁹Mo by selective solvent extraction or sublimation are also in use in some countries. ⁹⁹Tc^m is obtained from the generator in the form of pertechnetate solution; from the pertechnetate the ⁹⁹Tc^m is reduced to a lower valency cationic state and is then converted into various labelled pharmaceuticals. Preparation of short-lived radiopharmaceuticals produced from generators in usually undertaken in the hospital itself in a facility - called hospital radiopharmacy or a centralized radiopharmacy if it caters to the needs of more than one user hospital. Such centralized service may also undertake bulk imports of longer-lived radiopharmaceuticals and radiochemicals, dispensing and dose preparation, preparation of labelled compounds, quality control and training. This chapter describes the specifications of the commonly used radiopharmaceuticals, preparation of dosage forms of longer-lived products, in-house preparation of ''kits'' for short-lived generator-produced radiopharmaceuticals, their formulation and quality control

[en] The unsealed alpha-sources were designed and prepared to furnish 'Alpha-PXM' apparatus designed for analysis of Mars rock element composition and atmosphere by method of alpha back scattering, alpha-proton and X-ray fluorescence. The sources were prepared by high-temperature condensation of metal curium vapour on silicon substrates. The sources are silicon discs on which surfaces curium-244 as silicide is fixed. They have the following dimensions: disk of diameter 8 mm, active part of diameter 6 mm and 0.3 mm thickness. The sources activities are 5 + 1 mCi, alpha energy resolution (5.8 MeV): 1.7-2.5% FWHM, 2.9-4.5% FWTM. Performed thermovacuum (from -196 to 1000 degC), mechanical a resource tests showed the sources hold their characteristics. The sources were shown to be applied for the above mentioned analytical purposes. (author)

No abstract available

[en] Particle emitting radionuclides, e.g. Samarium-153, have been complexed with certain macrocyclic aminophosphonic acids wherein the nitrogen and phosphorus are interconnected by an alkylene group or substituted alkylene group. A composition is now disclosed which comprises a complex having a macrocyclic aminophosphonic acid, containing 1,4,7,10-tetraazycyclododecane as the macrocyclic moiety, or a physiologically, acceptable salt thereof, wherein the nitrogen and phosphorus are interconnected by an alkylene or substituted alkylene radical. 10 tabs

[en] Neutron irradiation of uranium, beginning in 1934, led to the reported discovery of such transuranium elements as eka-rhenium, etc. After a few years of investigation these were correctly identified, in December 1938, as fission products. The first real transuranium elements, with atomic numbers 93 and 94 (neptunium and plutonium), were discovered in 1940-1941. Not until it was recognized that transuranium elements should be part of a 14-member actinide series could elements 95 and 96 (americium and curium) be chemically identified following their nuclear synthesis. This new view was the key to the synthesis and identification of the next seven transuranium elements, resulting in the completion of the actinide series at element 103 in 1961. The transactinide elements could, according to the actinide concept, also be correctly placed in the Periodic Table and the chemical properties of the first transactinide elements, elements 104 and 105 (rutherfordium and hahnium), confirm this point of view. Transuranium elements through no. 109 are now known. There are possibilities for the discovery of more transactinide elements, including superheavy elements

[en] Synthesis is described which results in an iodinatable photoaffinity probe and derivatives which are useful in the covalent coupling of the probe to amine, carboxylic acid, and alcoholic hydroxy function on specific ligands of biological importance. Specific examples of natural product derivatization from terrestrial and marine sources are given. (author)

[en] Paroxetine (1), BRL 29060A, a potent antidepressant, has been prepared radiolabelled with carbon-14 in the methylenedioxy group in 5 steps and 20.9% overall yield from [¹⁴C]dibromomethane. Two alternative preparations of 3,4-[methylenedioxy-¹⁴C]phenol are also described. (Author)

[en] The benzodiazepine receptor tracer [¹²³I]iomazenil (Ro 16-0154, IMZ) can be prepared in close to theoretical specific activity by the reaction of its tributyltin precursor (IMZ-SnBu₃) with [¹²³I]NaI in the presence of Iodogen. However, the labeling reaction is associated with variably high amounts of a volatile ¹²³I byproduct. The purpose of these experiments was to characterize the volatile byproduct and to examine the effect on the course of the reaction of the following variables: solvent (MeOH, EtOH, HOAc, H₂O), pH (2-7), oxidizing agent (chloramine-T, Iodogen, AcO₂H), reaction temperature (22-128^oC) and structure of ArSnR₃). The volatile byproduct from the [¹²³I]IMZ preparations was identified as 1-[¹²³I]iodobutane by its trapping characteristics and by its retention time in two different HPLC systems. Volatile activity was not generated in the absence of Bu₃Sn precursor and was not due to the presence of impurities in the tributylstannyl precursor. (author)

[en] Short communication. 6 refs