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Abstract  

The installation of a multi-sample beta-gamma coincidence spectrometer in an underground laboratory with a rock covering of 47 m yielded further background reduction by factors of between 10 (at 2 MeV) and about 4 (below 1 MeV). In silicon samples Fe can be measured by neutron activation analysis with a detection limit of 40 pg.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. Garcia Alonso, D. Thoby-Schultzendorff, B. Giovannone, and L. Koch

Abstract  

Inductively Coupled Plasma Mass Spectrometry ICP-MS has been applied to the characterisation of various nuclear waste forms. Long-lived radionuclides can be determined with similar sensitivities. The installation of an ICP-MS in a glove box and applications and limitations of the methods to nuclear materials, with especial emphasis on isobaric interferences are described.

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It is a prime aim to ensure a suitable comfort level in case of office buildings. The productivity of office employees is directly influenced by the comfort. Thermal discomfort and poor indoor air quality deteriorate the intensity and quality of human work. We investigated the comfort in office buildings with on-site measurements during the summer season. The office buildings were operating with different HVAC (Heating, Ventilating and Air-Conditioning) systems: ducted fan-coil with suspended ceiling, installation, non-ducted fan-coil with floor-mounted installation, active chilled beam with fresh air supply.

We evaluated the thermal comfort under PMV (Predicted Mean Vote), PPD (Predicted Percentage of Dissatisfied), the local discomfort based on DR (Draught Rate) and the IAQ (Indoor Air Quality) based on carbon dioxide concentration. The comfort measurements were evaluated. The measurements were evaluated with scientific research methods, comfort categories based on the requirements of CR 1752. The results of this comparison were presented in this article.

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Abstract  

A debate has occurred recently over the issue whether it is possible to account for differences in results when using various versions of theScience Citation Index for the measurement of national performance in terms of numbers of scientific publications. This article provides an overview of the various arguments which have been made, and reports that recent reorganization in the on-line installations (SciSearch) should make it possible to circumvene one of the major sources of error.

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Abstract  

An installation for photon activation analysis recently completed at CBNM, Geel, is described. Synthetic standards prepared from pure graphite are used for the non-destructive determination of lanthanides in boron carbide. The induced activities of153Sm,152mEu,159Gd and157Dy were measured using a single open-ended coaxial Ge(Li) detector and the photopeak areas were calculated using the GAFIT program. For the irradiation parameters used, the limits of detection are communicated.

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The text deals with the work of Jana Želibská (1941 Olomouc) — flanêuse in the 1960s and the priestess of the Great Mother (Nature) in the 1970s. Želibská took a central position among male protagonists of neo-avant-garde in Slovakia. Her approach has been labeled ‘latent feminism’ because no real feminist platform existed during socialism in Slovakia. Želibská used the language of pop art and New Realism and their iconography mixed with the local folklore motifs in a quite different way. Pop art and New Realism entered the oeuvre of many artists simultaneously with experiments in conceptual art (Stano Filko, Peter Bartoš, Július Koller, Jana Želibská). After 1968, Želibská shifted the focus of her activities to land as an open structure outside of official supervision. Želibská made several statements regarding experiencing the magic of the present moment and experience with landscape through concepts and events that emphasized connection with nature. Photography helped her to work with continuity and causality in photo-sequences of situations and events. The path through ‘rooms of her own’ and other spatial concepts from the female labyrinth to the architecture of the temple in the 1960s, through changing open structures outdoors in her concept and land art in the 1970s, photography in 1980s, reached installation and video in the 1990s. Installations in the 1980s were built mainly on the artist’s experience with and in nature, or on the typical postmodernist contrast of the urban and natural. Puberty and virginity, which interested her in the land art events in 1970s, appeared again in her video art in a monumental demonstration of ‘girl power.’ In 1997 Želibská took the position behind the camera, shooting a naked male body without identity and face in the video installation Her View of Him. Thus she completed her shift from the ‘girl power’ of the 1960s and early 1970s agenda to fully articulated ‘woman power’.

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Abstract  

DTA method was used to follow the hydration process of cement admixtures containing fluidized bed combustion by-product, formed on joined combustion and desulphurisation in some installations with fluidized bed. Based on endothermic peaks attributed to the dehydration of phases formed on hydration, the conditions leading to the formation of so-called ‘delayed’ ettringite were found. This calcium alumino-sulphate hydrate is responsible for lower durability of fluidized bed ash containing material. DTA method is also beneficial in the studies of fluidized bed combustion by-product itself, giving information about the un-burnt carbon content and pozzolanic properties.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Lindstrom, R. Zeisler, E. Mackey, P. Liposky, R. Popelka-Filcoff, and R. Williams

Abstract  

For accurate activation analysis, it is necessary to understand the neutron and gamma-ray environment experienced by a sample during irradiation. A new irradiation position was recently installed in the RT2 thimble of the NIST reactor. Modeling by MCNP was used to select the radial location in the reflector thimble and the size of the D2O shielding tank. After installation, the new rabbit was characterized for thermal, epithermal, and fast fluence rates, spectral parameters f and α, temporal stability, axial and radial flux gradients, and temperature.

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Stone columns are used in practice for ground improvement of soft subsoil. Current design procedures of these columns are based on simple empirical calculations. This research project investigates the behavior of a base reinforced embankment constructed on a soft clay layer, which is improved with stone columns. Centrifuge tests were performed in order to gain a deeper understanding of the interaction problem within the structure. Stone columns were constructed in-flight using a newly developed installation tool. First analysis of test data shows a significant change in stress state due to column construction and the influence on the clay behavior.

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Abstract  

We present a framework for a multi-user server-based installation of the Shaman gamma-ray spectrum identification software. It allows users to access centrally managed Shaman and UniSampo software packages in a laboratory-wide multi-workstation environment. The server-based framework allows coordinated management of the software packages themselves as well as analysis parameter sets and analysis results either in a file system-based data vault or in an SQL-database based on the Linssi gamma-ray spectrometry database definition. Hierarchical management of analysis parameter sets allows full control of the individual analysis runs yet maintaining flexibility when analyzing a variety of sample types.

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