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78 Uppsatser om Trace - Sida 1 av 6

Spårelement i Sveriges jordbruksmark : flöden, trender och fältbalanser

Field balances based on supply and removal of Trace elements from the topsoil have been calculatedfor farms specialized in crop, dairy and pig production in Sweden. Today's field balances have beencompared with the field balances of 1990 in order to examine if, and then how, the situation haschanged. Studied Trace elements are arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu),mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn).The balance calculations show that the stores of Cu and Zn are depleted with an average rate of -15% and -6 % over a 100-years period on crop farms when only commercial fertilizers are being used.The concentrations of Hg and Pb tend to increase in the topsoil on crop farms with more than 3 % forHg and with 2 % for Pb in 100 years. There is today balance between supply and removal of the Traceelements As, Cd, Cr, Mn and Ni. In the south of Sweden, on crop farms with sugar beets in the croprotation, one can see a decrease in the concentration of Cd in the top soil by -6 % over a period of100 years.

Riktlinjer för modellering av reaktorkylpumpar i TRACE

Examensarbetet är utfört vid Ringhals AB och riktar in sig på reaktorkylpumparna på reaktor tre vid Ringhals kärnkraftverk (R3). R3an är en tryckvattenreaktor och reaktorkylpumparna är vertikala enstegs centrifugalpumpar som tillverkats av Westinghouse.Bakgrunden till detta examensarbete är att Vattenfall AB vill öka kunskapen inom modellering av LOCA (Loss-of-coolant Accident) och har startat ett projekt för modelleringen av detta i den termohydrauliska koden Trace. En viktig del i modelleringen av LOCA är hur reaktorkylpumparna beter sig när dom får hantera ett tvåfasflöde och då främst hur försvagad deras pumpförmåga blir.För att kunna göra en korrekt modell av pumparna i Trace behövs pumpkurvor för samtliga pumpregimer för både enfasflöde och fullt försvagat tvåfasflöde samt en kurva för hur pumpen reagerar på olika ånghalter. För de pumpar som finns på R3 finns bara kurvor för fyra pumpregimer för enfasflöde, så i dagsläget är det svårt att göra korrekta analyser av pumpförmågan.Syftet med arbetet är att få fördjupad förståelse hur reaktorkylpumparna beter sig vid ett tvåfasflöde och hur detta på bästa sätt kan modelleras för R3s pumpar och målet är att analysera och ge modelleringsförslag på bästa sättet att modellera reaktorkylpumparna i samband med tvåfasflöde.Examensarbetet har delats upp i två delar. En litteraturstudie för att utreda vilka pumpdata som skall användas för att på bästa sätt efterlikna pumparna på R3 och vad som gör att pumparna försvagas.

Växters upptag av spårämnen från rödfyr : ett odlingsförsök vid tre rödfyrshögar i Västra Götalands län

Burnt alun shale and lime is the residual product that was formed when alun shale was used as fuel to convert limestone to quick lime. The material contains arsenic, vanadium, molybdenum, cadmium, nickel, lead, and uranium among other elements. The aim of this paper is to examine the uptake of Trace elements in vegetables grown on burnt alun shale and lime to determine whether or not the surrounding environment and humans are exposed to these elements by eating plant products. A cultivation trial was carried out where onion, carrot, and lettuce were grown on three mounds of burnt alun shale and lime in the Falköping area in Sweden. The treatments were burnt alun shale and lime mixed with peat, only burnt alun shale and lime, and a reference soil. The reference plots were natural soil mixed with peat adjacent to the mounds.

Visualisering av produktionseffektivitet : Utveckling av ett verktyg för övervakningav avbrott och presentation av TAK

Many companies do not register all the stops that occur in a production plant, it often takes longer to report than to fix the problem. If no problems are registered, you cannot Trace where the problems arise.This master thesis was performed at AcobiaFLUX and they have noticed an increased demand from their customers to Trace problems raised in their processes. The aim of the thesis was to find out how a tool to monitor a process best could be developed. Then the most essential from the theoretical base was developed into a useful tool for operators. For the operators to know if the process utilizes the full capacity of a process, the tool presents a measure of the Overall Equipment Efficiency, OEE.

Concentration and offtake of trace elements and macronutrients in Italian ryegrass (Lolium multiflorum Lam.) and spring barley (Hordeum vulgare L.) grown on soils amended with water treatment residual sludge

Aluminium sulphate (Al2(SO4)3) is usually added during the drinking water treatment processin order to precipitate organic and inorganic material, resulting in aluminium-based drinkingwater treatment residual sludge (WTR). Since 2003 Swedish law no longer permits WTR tobe deposited in lakes, and there is an interest to explore the possibility to utilize WTR as soilamendment. The aim of this study was to examine the effects of WTR application on cropgrowth and concentrations of macronutrients and Trace elements (including micronutrients andpotential toxic elements). A greenhouse pot experiment was conducted with three soils; a clayloam rich in phosphorous (P), a loamy sand rich in P, and a silty loam with a low soil Pconcentration, and two crop species Italian ryegrass (Lolium multiflorum Lam. cv.

Jag vill, men hur? Ett utforskande av den kreativa processen.

I want to, but how? My work is a research of the creative process. I have asked myself how ideas take form and how materials can become bearers of ideas. The work has been treated as an action rather than an object. The result shows my research and my interpretation: the process and result are the same..

En undersökning av ljus av ljus - den omvända skuggbildningen

This work is an exploration of a method and how to find balance between it and its contents. One part consists of a technical study on how to use UV light to yellow distinct surfaces on paper and the other is about how to find use of the method. The common denominator is determined as the consequence of the relationship between light and time. The result is three images that shows various Traces of time with time as a graphic expression..

Utvärdering av rörelsemönster hos öring (Salmo trutta) utifrån otolitmikrokemi

The classic view of trout (Salmo trutta) life history is that trout begins its life in freshwater, migrates to the ocean after about 1-4 years and then returns to freshwater to spawn. As trout fry have been caught at the mouth of the River Emån, near the Baltic Sea, researchers have speculated that some trout emigrate during their first year of life. The purpose of this study was to describe the variation in the length of time trout reside in freshwater before they migrate to the ocean for the first time. Another purpose was to investigate whether it was possible to discern where and how long the fish spent in freshwater and saltwater during different parts of their lives. Between 2007 and 2009, 23 adult trout were captured in the River Emån in southeastern Sweden.

Tankar kring Torsk : Isotopanalyser av torskkotor för att undersöka vikten av torskimport i medeltida Sverige

This essay discusses the import of cod (Gadus morhua) in Sweden during the Middle Ages through isotope analysis of cod vertebrae. The isotope analysis is used to Trace the cods origin to either the Baltic Sea or the Atlantic Ocean. The bones were subjected to d13C, d15N and d34S analysis; 64 of  the analyzed bones met the quality criteria. The isotop data showed that import of Atlantic cod was significant in medeval Sweden. The analysis suggests that there is no specific time or event that the sites start to import cod but this varies from site to site. .

Gränser i Grödinge : Om hägnadsanläggningars funktion med utgångspunkt i en fosfatanalys av RAÄ 78 samt RAÄ 79 i Grödinge sn på Södertörn

This paper deals with the question of when hill forts ? or enclosed mountains ? were built and to what purpose, by examining two enclosed mountains (RAÄ 78 and 79) in Grödinge parish in the province of Södermanland. A phosphate analysis was conducted to Trace anthropogenic activities. The analysis showed only a slight elevation of phosphate content in the soil. A histogram indicated that the elevations were not normally distributed, which could suggest that they were caused by anthropogenic activities.

Utvärdering av individuellt märkt text

With the development of the Internet, illegal copying of electronic documents has become a growing problem. There is an increasing need of prevention in the field of pirate copying. One method is to mark the document by changing some of the words to synonyms. In this way it is possible to construct legal copies which do not differ in content but still are unique. Since the copies of the documents are unique, it is possible to Trace the owner of a document and accordingly call him or her to account for pirate copying if several exactly similar copies are reaching the market.

read me. do you copy ? - en undersökning av litterär interaktionsdesign i utställningsrummet

We are heading for a line, and its a fine one. This project is a dialogue between you and I; about the dialogue itself. The initial interest was to use literary text to address the visitor in the exhibition space. The purpose was to make man aware of its relation to others and narrative objects. I planned for the dialectical event in every descision.

Adonis - från Mesopotamien till Grekland

This paper attempts to Trace the journey of Adonis from ancient Mesopotamia, through Phoenicia and finally to Greece, and to see how his function and cult have evolved during this migration. It starts with a short summary of previous research regarding Adonis and goes on to describe the myths and the rites of Adonis as they were celebrated in Alexandria, Byblos and Athens. I then examine possible connections to ritual drama, the mystery religions and whether there is any evidence that the Adonia might have been a germination ritual.My conclusions are that Adonis loses his connection to the growing cycle and the ideology of sacred kingship with the move to Greece where the political system with independent city states is different, and that there has been too much focus on Adonis as a vegetation god. Since Adonis is connected with the ancient Near Eastern cults of sacral kingship it might be more rewarding to consider the death aspects associated with his cult and the possibility of ancestral worship in relation to a ruler. This would make some of the otherwise puzzling aspects of his cult more understandable..

Hälsa som huvudsak : En diskursanalys av hälsa i populärmedia

The purpose with this master´s thesis is to examine how helth and unhelthy in the Swedish magazines Topphälsa, Fitnez Magazine, hälsa and I Form. The study is made from a discourse analytical approach and text and pictures are analysed together. The governmentality-perspective is also used as a theoretical frame. Power and govern are two inportant conceptions for this paper. Some of the main characteristics of the material are the double messages, the division in the categories "we" and "them" and the personal address to the reader.

Slagfältarkeologi : Metod och möjlighet att lokalisera och undersöka förhistoriska bataljplatser.

This essay is a study regarding the existence of Bronze Ages and Iron Ages battlefields in Scandinavia and the possibility to Trace and find them by using the Battlefield Archaeological Method.Based on a theoretical background and results from historical battlefield research and excavation experiences, the discussion deals with some of the problems and possibilities of applying the Battlefield Archaeological Method on older places. The existence of these battlegrounds is also an unknown factor, and a major part of this study is trying to find evidence of their existence. For that purpose I am using as an example a deeper analysis of an Iron Age battlefield archaeological excavation in Germany in order to compare and draw parallels with the Scandinavian society of that time. I am also using the evolution of weaponry, in particular the sword, to show parallels between the Mediterranean and the Scandinavian societies in the matter of warfare and tactics..

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