[en] We have reported the chemical synthesis and D₂ dopamine receptor affinity of 3-N-(2-fluoroethyl)spiperone. The receptor affinity of this compound, as measured by an in vitro assay, is nearly the same as spiperone. (author)

[en] The development of methods to prepare ¹¹C-labelled peptides and proteins provides new tools to investigate biological processes in man by PET. A new method of ¹¹C-labelling by the addition of ¹¹C-amino acid to an appropriate precursor peptide is described. (author)

[en] N-[¹¹C-Methyl]Chlorphentermine (¹¹C-NMCP) has recently been developed in our laboratory as a potential brain blood flow agent for PET studies. The radiochemical yield of ¹¹C-NMCP was substantially low because the reaction gave a mixture of mono-, di-and quarternary amines. To improve the radiochemical yield of ¹¹C-NMCP, we investigated the Gabriel-like transformation of the primary to the secondary amine through a sequence of acylation, ionization, alkylation and hydrolysis. (author)

[en] The preparation of ¹¹C-labeled peptides by the route originally developed for the synthesis of ¹¹C-methionine has now been extended to the synthesis of the undecapeptide Substance P. Problems in the preparation of the substrate have now been solved. (author)

[en] To permit PET studies of brain binding in vivo, prostaglandins or prostaglandin analogues were subjected to labeling syntheses with ¹¹C. Our first approach was to synthesize prostaglandin methyl esters, labeling the alcoholic part of the ester. (author)

[en] The dc electrical conductivity of a series of Lasub(2 -x)Srsub(x)CuO₄ compounds has been investigated. At room temperature the compounds exhibit a continuous change from the orthorombic to the tetragonal structure as x is increased from zero to x = 0.15. Superconductivity appears in the tetragonal phase. The resistivity maximum, preceeding the superconducting transition varies in correlation with the Sr concentration. Application of hydrostatic pressure supresses the resistivity maximum. (author)

No abstract available

[en] A considerable amount of experience has been amassed during the seven years of operation of the Tricastin enrichment plant. This experience has been used to provide rapid and effective solutions to problems met during startup, to make improvements, and to acquire in-depth knowledge of the plant's performance under a broad range of operating conditions. (author)

[en] The gas centrifuge is not only considered more than a match for lasers for at least the rest of this century, but also the particular technical characteristics of the process make it especially suitable for re-enriching reprocessed uranium. (author)

[en] The regeneration of biologically clogged water wells by radiation proved to be a successful and economically beneficial process among other promising applications of ionizing radiation in the water supply technology. The application conditions and experience are mentioned. The potential pathogenic Mycobacteria occuring in the warm washing and bathing water are resistant against usual chlorine and ozone concentrations. The radiation sensitivity of Mycobacteria allowed to suggest a device for their destroying by radiation. Some toxic substances in the underground water can be efficiently degraded by gamma radiation directly in the wells drilled as a hydraulic barrier surrounding the contaminated land area. Substantial decrease of CN^- concentration and C.O.D. value was observed in water pumped from such well equipped with cobalt sources and charcoal. The removing of pathogenic contamination remains to be the main goal of radiation processing in the water purification technologies. The decrease of liquid sludge specific filter resistance and sedimentation acceleration by irradiation have a minor technological importance. The hygienization of sludge cake from the mechanical belt filter press by electron beam appears to be the optimum application in the Czechoslovak conditions. The potatoes and barley crop yields from experimental plots treated with sludge were higher in comparison with using the manure. Biological sludge from the municipal and food industry water purification plants contains nutritive components. The proper hygienization is a necessary condition for using them as a livestock feed supplement. Feeding experiments with broilers and pigs confirmed the possibility of partial (e.g. 50%) replacement of soya-, bone, or fish flour in feed mixtures by dried sludge hygienized either by heat or by the irradiation. (author)