958 resultados para Geiger-Müller counters.


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Asymmetric emission profiles of the stereoisomers of plant-derived volatile organic compounds vary with season, geography, plant type, and stress factors. After oxidation of these compounds in the atmosphere, the low-vapor pressure products ultimately contribute strongly to the particle-phase material of the atmosphere. In order to explore the possibility of stereochemical transfer to atmospheric aerosol particles during the oxidation of biogenic volatile organic compounds, second-order coherent vibrational spectra were recorded of the particle-phase organic material produced by the oxidation of different stereoisomeric mixes of alpha-pinene. The spectra show that the stereochemical configurations are not scrambled but instead are transferred from the gas-phase molecular precursors to the particle-phase molecules. The spectra also show that oligomers formed in the particle phase have a handed superstructure that depends strongly and nonlinearly on the initial stereochemical composition of the precursors. Because the stereochemical mix of the precursors for a material can influence the physical and chemical properties of that material, our findings suggest that chirality is also important for such properties of plant-derived aerosol particles. Citation: Ebben, C. J., S. R. Zorn, S.-B. Lee, P. Artaxo, S. T. Martin, and F. M. Geiger (2011), Stereochemical transfer to atmospheric aerosol particles accompanying the oxidation of biogenic volatile organic compounds, Geophys. Res. Lett., 38, L16807, doi: 10.1029/2011GL048599.

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The Southwest region of the Bahia state in Brazil hosts the largest uranium reserve of the country (100 kton in uranium, only), plus the cities of Caetite, Lagoa Real and Igapora. In this work, aim was at the investigation of uranium burdens on residents of these cities by using teeth as bioindicators, as a contribution for possible radiation protection measures. Thus, a total of 41 human teeth were collected, plus 50 from an allegedly uranium free area (the control region). Concentrations of uranium in teeth from residents of 5- to 87-y old were determined by means of a high-resolution inductively coupled plasma mass spectrometer (ICP-MS). The highest uranium concentration in teeth was measured from samples belonging to residents of Caetite (median equal to 16 ppb). Assuming that the uranium concentrations in teeth and bones are similar within 10-20% (for children and young adults), it concluded that uranium body levels in residents of Caetite are at least one order of magnitude higher than the worldwide average. This finding led to conclude that daily ingestion of uranium, from food and water, is equally high.

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Electron transport parameters are important in several areas ranging from particle detectors to plasma-assisted processing reactors. Nevertheless, especially at high fields strengths and for complex gases, relatively few data are published. A dedicated setup has been developed to measure the electron drift velocity and the first Townsend coefficient in parallel plate geometry. An RPC-like cell has been adopted to reach high field strengths without the risk of destructive sparks. The validation data obtained with pure Nitrogen will be presented and compared to a selection of the available literature and to calculations performed with Magboltz 2 version 8.6. The new data collected in pure Isobutane will then be discussed. This is the first time the electron drift velocity in pure Isobutane is measured well into the saturation region. Good agreement is found with expectations from Magboltz. (C) 2009 Elsevier B.V. All rights reserved.

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I denna uppsats som i sin allra enklaste form är en analys av ledmotivsanvändningen i filmen Sagan om Ringen ville jag ta reda på vilka olika narrativa funktioner dessa ledmotiv kan ha. Genom att jag genomförde en analys där jag såg filmen i kronologisk ordning och tittade på två slumpmässigt utvalda ledmotiv och deras berättande funktioner kom jag fram till att ledmotiven verkligen har en central roll i filmens musikaliska struktur. Ledmotiven används föra att underbygga den fortskridande handlingen och hjälpa publiken följa med i denna. Samtidigt klargör vissa av dessa ledmotiv saker i handlingen som annars skulle vara dolda, saker som inte berättas med vare sig ord eller bilder utan med musik.

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The digital printing market is changing faster now than before and the ability to adjust to newsituations has become more importat to a printing company. An efficient internal communicationis essential. At Elanders Digitaltryck a decision was made in august 2002 to look over the shiftworking system for the printer operators. In this paper, an investigation of the possibilities tochange the existing system to a better one was made.The project resultet in four different timetabels. The construction was based on theoretical studiesand an analysis of the current situation at the workplace. The analysis showed that a strong resistanseagainst a change of the working hours exists among the workers and that this should beconsidered before a decision is made. An analasys of the printers counters shows that they areused more efficient during shorter shift periods compared to the longer ones. A closeer look at theabcense due to sickness shows that it is relatively high but no connection between abcense andworking hours could be made.Working hours is a sensitive issue and should be treated with care. It is important that the workersare well informed and preferly involved in the development of a new timetable.

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Bobergs printing house in Falun has during some time had problems regarding deposits on blankets intheirs Müller Martini UV-printing presses. Deposits appear in both image areas and non-image areas.These areas have been analyzed and the deposits on non-image areas contain chalk, clay and talc. Thequestion remains how these material bond to the blanket surface. The chalk and clay comes from thepaper. The talc comes from the ink. Deposits from image areas contain pigment and talc from the printingink. The dampening water has also been analyzed. The result shows some sort of problem with thehardness regulator for the clean water. The pH-level should be increased a few steps.

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In Sweden the number of rural food shops has decreased for more than 50 years. Often the closing of a village shop is supposed to affect the migration patterns in the area it has been serving. However, according to this study, neither in- nor out-migration in the area affected by the closing is affected. The deficits of migration usual in those areas are established at least 10-12 years before the closing year. Thus, the typical closing takes place subsequent to a long term population decline. On the other hand, localities hosting a shop that survived during the study period 1990-2004 have a bigger total population and show tendencies towards decreasing deficit of migration at any potential closing year. These statistical results are supported by interviews carried out in three villages where the last shop has closed. They indicate that the shop has already lost its importance as supplier when it closes. By then the village shop is primarily used as complement to nearby towns or shopping centres. Each of the two studies accounted for here point at a relative un-importance of the village shop as a service point at the closing time. However, as it often offer the last public space in the village the village shop serves a key function as a meeting point for some households. When the shop has closed, the village holds private homes only. That is a situation increasing loneliness to some inhabitants.

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Denna rapport behandlar förutsättningar för regionala utvecklingseffekter av en väginvestering. Projektet är en inledande studie kring effekterna av vägen mellan Falun och Borlänge som öppnades för trafik 2005. Projektet är finansierat av Vägverket. Projektet avser att besvara två huvudsakliga frågeställningar: Vilka samhälleliga effekter får en ny väg mellan två städer som ligger inom samma lokala arbetsmarknad? Kan betydelsen för en region av en väginvestering påverkas genom medvetet arbete från regionens aktörer för att utnyttja dess potential? I vår studie går vi bortom själva tidsvinsten och fördjupar oss i hur utbytet mellan de två kommunerna ser ut och förändras. Vi vill också komma åt orsakerna till dessa förändringar. Det är intressant för oss hur aktörernas perspektiv och förväntningar omvandlas till beslut kring resande, byggande, kollektivtrafiksatsningar osv. Betydelsen av den nya vägen avgörs till stor del av hur regionens aktörer ser på den och agerar för att ta vara på dess potential.Studien kan ses som en förstudie. Avsikten har varit att studera utbytet mellan orterna innan vägens färdigställande och att kartlägga synen på regionens potential, vägens betydelse hos företrädare för näringslivsorganisationer, större arbetsgivare, politiker, m fl. Frågorna måste besvaras genom flera olika delstudier med skilda perspektiv. Vi har arbetat med intervjuer med beslutsfattare i den berörda regionen, vi har studerat pendlingsrörelser, analyserat kollektivtrafikens utveckling och vi har försökt att sätta in vägen i ett regionalpolitiskt utvecklingsperspektiv. Fokus i studien ligger på institutionella förhållanden och begrepp och processer i regional utveckling.

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The Arctic is affected by global environmental change and also by diverse interests from many economic sectors and industries. Over the last decade, various actors have attempted to explore the options for setting up integrated and comprehensive trans-boundary systems for monitoring and observing these impacts. These Arctic Observation Systems (AOS) contribute to the planning, implementation, monitoring and evaluation of environmental change and responsible social and economic development in the Arctic. The aim of this article is to identify the two-way relationship between AOS and tourism. On the one hand, tourism activities account for diverse changes across a broad spectrum of impact fields. On the other hand, due to its multiple and diverse agents and far-reaching activities, tourism is also well-positioned to collect observational data and participate as an actor in monitoring activities. To accomplish our goals, we provide an inventory of tourism-embedded issues and concerns of interest to AOS from a range of destinations in the circumpolar Arctic region, including Alaska, Arctic Canada, Iceland, Svalbard, the mainland European Arctic and Russia. The article also draws comparisons with the situation in Antarctica. On the basis of a collective analysis provided by members of the International Polar Tourism Research Network from across the polar regions, we conclude that the potential role for tourism in the development and implementation of AOS is significant and has been overlooked.