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Abstract  

The paper deals with the problem of the outpatient administration of186Re-HEDP and153Sm-EDTMP for palliative therapy of bone metastases. The subsequent 6 hours stay of the treated patients in a department of nuclear medicine appears to be in compliance with regulations proposed in the Czech Republic as well as with ICRP recommendations.

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Abstract  

The Czech Republic has two nuclear power plants (NPPs) equipped with light water pressurized reactors (LWPR). Annual sampling of biota for 14C activity monitoring by Nuclear Physics Institute in cooperation with the National Institute of Radiation Protection started in 2002. We present the results of biota monitoring covering two sampling periods 2002–2005 and 2007–2008. The considerable problem in the case of biota sampling for monitoring purpose is given by a relatively short period of biota accumulation for prevailing types of biota samples (leaves of deciduous trees or agricultural plants), which usually lasts from several weeks to 2 months. The short period of sample accumulation can also be partly overlapped by a service period of reactor outage in a given NPP. On the base of our several years’ experiences we have changed a type of the sampled material to reduce variations of observed activities and to precise reference levels in the exposed and reference sites.

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Abstract  

At the Special Sessionk 0 of the MTAA-8 (Vienna, 1991), and later on at the Intemationalk 0 Users Workshop-Gent (1992), progress was reported with respect to the development and use of computer codes in order to mould thek 0-standardization of neutron activation analysis into an effective working instrument. Among others, this resulted in the software package KAYZERO for PC DOS, which was designed and distributed by DSM Research (Geleen, NL), and which is based on thek 0-methodology, algorithms and nuclear data file developed and created at the INW (Gent, B) and the KFKI (Budapest, H), the traditional k 0-centres. One of the most recent initiatives is a project in the framework of the COPERNICUS programme of the Commission of the European Union. It uses the synergism of a Joint Research Project to give an impulse to the exploitation of KAYZERO-assisted NAA as a manageable and competitive analytical tool in industry and environmental sanitation in Hungary, the Czech Republic and Slovenia. An outline is given of the strategy worked out in this JRP, emphasizing the procedures applied in the three institutes for the calibration of their irradiation facilities and Ge-detectors, quality control and assurance procedures following the implementation of the method, and the identification and tackling of the practical analytical problems which are of relevance to the Central European partner countries.

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Abstract  

The fruit bodies of wild-growing higher fungi (macromycetes), commonly called mushrooms, of various genera and species collected in localities with different geochemical features and man-made burden in the Czech Republic were analyzed by different modes of activation analysis. The elements Na, Mg, Al, S, Cl, K, Ti, V, Mn, Cu, Br, Ba and Dy were determined by short-term instrumental neutron activation analysis (INAA). Short-term epithermal INAA (ENAA) was used for determination of I and other elements, such as Rb, Ag, and U. The elements Na, K, Sc, Cr, Fe, Co, Cu, Zn, As, Se, Br, Rb, Ag, Cd, Sb, Cs, Ba, La, Ce, Sm, Eu, Hf, Au, Hg and Th were determined by long-term INAA, whereas long-term ENAA enabled determination of several other elements, such as Ni, Ta, W and U. The analytical possibilities of instrumental photon activation analysis (IPAA) using a microtron were also explored and found useful for determination of several additional elements, namely Sr, Y, Zr, Nb, and Pb. High concentrations of several essential and toxic trace elements found (up to hundreds of mg.g-1, dry mass) should be of concern in nutritional studies, because mushrooms form non-negligible part of diet in many countries, especially in Middle and East Europe.

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Abstract  

This contribution compares measured neutron energy spectra and neutron fluence rates in the LVR-15 reactor core fully equipped with IRT2M nuclear fuel (enrichment 36% of 235U in the form of UO2) and then with a partially replaced core equipped with three IRT4M nuclear fuel assemblies (enrichment 19.7%). The measurements were performed in the LVR-15 reactor at Research Center Rez Ltd. in the Czech Republic, and were related to a planned transition to low-enriched nuclear fuel within the scope of the RERTR programme. An activation method was chosen for the neutron spectrum measurement. Iron, cobalt, nickel, copper, titanium, iridium and niobium foils were irradiated at four positions near the replaced fuel assemblies. Reaction rates for observed reaction channels were determined using gamma spectroscopy. Reaction rates along the height of the reactor core at the same positions were determined using iron, nickel, and cobalt foils. The SAND-II and STAYNL computer programs were used for neutron spectrum adjustment, and input approximation for both programs was calculated using MCNPX (v2.6). The results include a comparison of theoretical and measured data. Differences were found between thermal neutron fluence rates inside IRT2M fuel assemblies and IRT4M fuel. This difference was predicted by preliminary calculations, but it becomes less significant as distance from fuel assemblies increases.

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Prof. Ing. Zdeněk Šolc, CSc (21 September 1931–30 September 2006) Prof. Zdeněk Šolc was born in 1931. After finishing his university studies, he joined the University of Pardubice where he remained for more than 50 years. He started to work at the Department of Physical Chemistry. His main fields of interest were: preparation of monocrystals, crystallization from solutions, measuring of physical and chemical properties of solutions. In the 1960's he turned to inorganic technology, studying inoranic pigments and he moved to the Department of Inorganic Technology. In this vast area of science, he achieved his greatest successes, and pigments became his ever-lasting passion up to the end of his life. The research in the field of crystallisation was oriented to development of liquid crystals for use in temperature indication, and materials for integrated circuits; besides that a school of inorganic pigments was formed (M. Trojan, Z. Šolc, D. Brandov) whose main orientation is mixed oxide materials for use in ceramics and enamels. A predominant part of the mentioned research activities was pursued at KAnT in 1990–1996, when the Department was headed by Professor Ing. Zdeněk Šolc. Most of Prof. ŠolcŠs projects were focused on the reactivity of inorganic pigments and powder materials, research of their high-temperature syntheses and rating of their physical and chemical properties. He applied mainly simultaneous thermal analytical techniques: thermogravimetry, differential thermal analysis using dynamic measuring conditions and quasi-isothermal and quasi-isobaric ones, moreover emanation thermal analysis and thermal conductivity measurements. Prof. Zdeněk Šolc was a creative scientist. He published more than 50 scientific papers in international journals and wrote 10 textbooks. He was the author of almost 100 lectures of conferences held in the Czech Republic and foreign countries. He had a silent but a very kind personality and he will be missed very much both by the local and the international communities. Requiescat in pace

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Summary  

Fruitbodies of wild-growing macromycetes (mushrooms) of various genera and species collected in localities with different geochemical features and man-made burden in the Czech Republic were analyzed using the short-term instrumental neutron activation, with both thermal and epithermal neutrons. Analytical possibilities of these methods were compared. Na, Mg, Al, Cl, K, Ca, V, Mn, Cu, and Br were determined regularly, whereas S, Ti, Rb, Cs, Ba, and Dy were determined occasionally with thermal neutron activation at irradiation-decay-counting times mode of 1-10-10 minutes. Because of high concentration of K and P in the macromycete dry matter (2-7% and 0.5-1%, respectively) and also high Cl concentration in some genera (up to 2.5%), all “1/v” absorbers, epithermal neutron activation in Cd box (1 mm thick wall) substantially suppresses their macroactivities and enhances sensitivity in the determination of elements with significant resonance integrals. Cu, Se, Rb, Ag, Hf, and sometimes Ba are determinable in the mode of 60-30-60 seconds, while K, Cu, As, Br, Rb, In, I, U (in some species also Co, Zn, Cs, Ba, and Hg) in the mode of 1-13-13 minutes. However, Na, Mg, Al, Cl, and Mn determination is not possible this way, as the (n,p) and (n,α) interfering reactions with fast neutrons and high K, P, and other interfering elements content make great interference contributions. Information about content of the essential and toxic elements in mushrooms is important in nutritional studies, because mushrooms form a non-negligible part of diet in many countries.

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from the Institute of Chemical Technology in Prague. He is a fellow of Engineering Academy of the Czech Republic (EACR), member of the scientific board of the Czech Science Foundation (CSF), and member of the Council of International Confederation for

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various research institutions of the Czech Republic and Slovakia. The group represents extensive publications, which also related to an important bibliographic citation response and is associated with the names as Arnošt Bergstein, Antonín Blažek

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. Institute of Hydro-Engineering (Polish Academy of Sciences, Gdańsk, Poland) 2 months 1991. Institute of Inorganic Chemistry (Academy of Sciences of the Czech Republic, Rez, Czech Republic), 4 weeks each: 1994, 1998, 1999, 2001

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