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371 Uppsatser om Metal contaminated soils - Sida 13 av 25

Metallersättning inom byggbranschen

In this paper the possibilities to replace metal with plastic in products for the building industry were looked into. The first part was a market examination where several suitable products were found. After evaluation the door latch for in-house doors was selected to be re-designed to better suit the properties of plastic.New types of mechanisms were designed with different functions that use the benefits of plastic materials. Models of these mechanisms were developed to evaluate their function. The components in the different mechanisms were adapted for manufacturing with injection moulding.To confirm that the plastic material could handle the appearing stresses calculations on the most vulnerable parts were carried out.

Exosomes as a potential mechanism of intercellular spread of prion protein

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Pulveregenskapers inverkan på grönkropp med avseende på sprickor

This thesis is a survey and also an investigation of the different factors that affects the cracking that occurs in the inserts at AB Sandvik Coromants production in Gimo. The work that has been done has focused on two main factors, namely, powder characteristics and pressing parameters.AB Sandvik Coromant produces tools and tooling systems for metal cutting. They have some problems in their production of inserts. The problem is that cracks sometimes occur in the body of the insert, after it´s pressed. In order to investigate this, a preliminary study was made in which production principles were studied.

"Underhållsfria fönster" : I vilken utsträckning är dagens "underhållsfria" fönster underhållsfria och hur ser man

AbstractThe aim of this examination paper is to get an overview on the ?no-maintenance? windowsthat exist on the Swedish market, like plastic and aluminium windows.By way of introduction the reader gets knowledge in the background and problemformulatethat this subject has. This introduction explains why it has become so popular to changeyour windows into plastic- and aluminium windows and there is an existing scepticismagainst PVC and aluminium as construction material for windows.The main part of this report is constructed by segments of interviews where bothproducers of windows and stakeholders gets to answer questions about their viewing onno-maintenance windows from a material and construction point of view and where theproduction is headed to in the future. This is followed by an evaluation of a questionnaireon how pleased the house owners that changed their old windows to no-maintenancewindows are, followed by an inspection of windows made up from wood and an aluminiumclothing, windows made from only aluminium and PVC-based windows. It ends with atheory part about the materials PVC and metal based upon facts included in literature.By reading this report you can draw the conclusion that no window can be entirely nonmaintenancebut that the materials PVC and aluminium still are good substitutes for woodto lessen the maintenance..

Metodundersökning av tre metoder för kvävemätning i en arktisk äng : Jämförelse mellan mätmetoderna extraktion, inkubation och jonbytesmembran (PRS-sond)

The purpose with this report was to compare three commonly occurring methods for measuring plant available nitrogen in soils. The methods extraction, incubation and Plant root simulator (PRS) probe - an ion exchange membrane (Western Ag Innovations, Inc., Saskatoon, Canada) method were used and comparison between these methods were conducted. A full factorial experiment were set up in northern Finland with the treatments excluding herbivores, warming and fertilization to see how the inorganic nitrogen content in the soil was effected by the treatments. Soil cores were taken and from them a subsample was incubated for 18 days and thereafter analyzed for inorganic N in laboratory. PRS- probes were in the ground for 1 month.

Människan, kalven eller gödselbrunnen? Mjölkens destination och fördelning - hos mjölkbonden

A variety of food is produced and passes the whole chain by processing, transport and trade and finally it ends up with the consumer. But in many cases, the food is disposed before it is eaten. Some of the produced food does not even pass the whole entire chain before it turns to waste. The question about food waste in debates is a case of access to food for every human beeing. It is question of consumption of the resources, waste management and an issue of environmental impact.

Inköpsoptimering och kostnadsreducering

This thesis has been carried out at Diac Metal AB at Torsvik outside of Jönköping. The company produces parts for, amongst others, office furniture and store equipment. The essay will be concentrated on one detail which is included in many of their products.Today the company uses an ordering quantity based on experience which is rarely updated. Furthermore the operations are performed in both the company?s own engineering workshop but also an external workshop.The purpose with the report has been to check whether an updating of today?s batch shaping and ordering system can mean simpler storage control and possibly cost reduction.

Guld i Sverige - Från urtid till nutid

The Earth and everything else in the universe was created in the Big Bang around 14 billion years ago. A point with tremendous density and mass began to expand and more and more atoms began to form. From the first and lightest like hydrogen and helium to heavier atoms such as iron and eventually gold. The formation of the Earth occurred about 4.6 billion years ago and so the first gold atoms were concentrated only here. It is however believed that much later in Earth's history an extra supply of gold occurred thanks to massive meteorite bombardments.

Hassel (Corylus avellana) som indikator på markanvändningshistorik

Hazel (Corylus avellana L.) is a common feature of meadows and pastures where it can grow in large populations and become very old. Is it possible to use the size of hazel stools for age determination and is it possible to use the size distribution of a population to provide information about how the land has been used? Hazel populations on ground where the lake-water level had been lowered, has been studied to validate an already developed growth model of hazel clones. Different hazel populations, on wooded meadows affected by mowing or grazing or overgrown meadows, were studied to evaluate the method utilizing hazel as land use indicator. The growth model was used to compare the size distributions of hazel populations with historical periods, which has been important for changes in agriculture or demography.

Material och kvalitet, en studie för skärande bearbetning i stångmaterial

På uppdrag av Skärteknikcentrum Svergie AB i Gislaved gjordes en undersökning av driftstörningarna i produktionsprocessen hos tre olika medlemsföretag som kunde kopplas direkt till kvalitet på stångmaterialet som används. Undersökningen gjordes hos Gnosjö automatsvarvning AB, Finnveden Powertrain (Alvestafabriken) och Bufab Lann AB, alla arbetar med stångmaterial och har liknande tillverkningsprocesser. Uppgiften gick ut på att identifiera ifall det finns driftstörningar som enbart är beroende av kvaliteten på materialet samt vilka problem de leder till. Efter genomförda undersökningar och en större inblick hos de olika företagen konstaterades det att variationer i kvaliten på materialet har en effekt på hur produktionsprocessen fungerar. Störningar i produktionen kan reduceras ifall materialet egenskaper förbättras eller tillverkningsprocessen ändras.

Vanvårdens inverkan på nötkreaturs välfärd och hälsa

Farmers are required to make sure that cattles basic needs are met, but still every year cases of neglect occur where the farmer has not complied within the animal welfare law and regulations. The aim of this study was to investigate how cattle are affected physically and behaviourally by neglect in the form of underfeeding, starvation and lack of sanitation, which animals are most vulnerable to the impact and what prospects they have to recover. The study was conducted as a literature study and the results show that these types of neglect have a large impact on the cattle welfare. Underfeeding and starvation causes physical changes leading to reduced milk production, reduced muscle mass, impaired immune function, poor reproductive performance and changes in rumen microflora leading to decreased number of microbes and pH change. Physical changes due to the lack of sanitation consist of increased vulnerability to hoof diseases and mastitis, burns, and increased sensitivity to temperature.

Modellering av oorganiskt kol i boreal jord och vattendrag med hjälp av PHREEQC : Modelling of dissolved inorganic carbon in boreal soils and streams using PHREEQC

Syftet med examensarbetet har varit att studera kol i mindre vattendrag med hjälp av jämviktsmodellering i PHREEQC. Fokus har varit dynamik av löst icke organiskt kol (DIC) samt att förstå hur mycket koldioxid (CO2) som avges från mindre vattendrag och om den mängden har signifikant inverkan på den globala kolbalansen. Med hjälp av provtagen data från Krycklans avrinningsområde år 2003-2007 och 2009 har modellering av DIC och pCO2 utförts med målet att se förändring både över säsong och nedströms i ytvattensystemet. För att utvärdera modellen har tillhandahållen data över uppmätt pCO2 använts. Målet var att jämföra modellerade och tillhandahållna pCO2-värden för att se hur väl modellen kunde beskriva verkligheten och om den fungerade bättre för någon plats eller under vissa delar av året.

Marktillstånd och borbrist på åkermark planterad med gran i Västerbottens län :

This study was made on former agricultural areas that had been planted with spruce or pine, in the county of Västerbotten. The goal of the project was to investigate suspected deficiency of boron in these areas. Several objects have been reported for possible deficiency and some of these have the characteristic symptoms of boron-deficiency. The hypotheses are that 1) Boron deficiency is present at several of the investigated objects. 2) Planting of forest on cultivated postglacial sediments leads to a successive podzolisation with a decreasing content of organic matter in the mineral soil, due to decomposition, and a decreasing pH in the soil, even on locations that have been added lime. To be able to confirm or reject the hypotheses a number of tests were performed.

Standardisering av snöröjningsplan : Instruktioner, råd och tips för snöröjning av tak med stora spännvidder

The Swedish winters 2009/10 and 2010/11 were rich in snow and many roofs collapsed, mainly largespan frames. Investigations were made and the amount of snow was not the primary cause, insteadthere were several other causes. One of these was that in some cases roofs were shoveled in anunfavorable manner which affected the load patterns negatively, so causing the roofs to collapse.Most people lack the knowledge of how shoveling will affect the roof. Had there been an increasedunderstanding regarding shoveling, some roofs could have been prevented from collapsing.Through both qualitative and quantitative research in the form of interviews and calculations thetheoretically best ways to shovel a selection of roof types is presented in the report. The roofstructures covered are 3-compartment, continuous and Gerberspliced metal roof decks.

Undersökning av titanföreningar för tillverkning av standarder vid användning av röntgenfluorescens

SECO Tools manufactures tool inserts for all types of metal cutting machining. (Ti,W)C is a common raw material used in the production. At arrival, the material (Ti,W)C is always analyzed. Titanium has previously been analysed with x-ray fluorescence spectrometry, but as the calibration has previously been performed with two different types of titanium (rutile and metallic titanium), the results has differed. Because of that, this thesis project has been devoted to analyze titanium, to find the best titanium compound for producing standards.The work has been performed using literature studies and many experiments in the laboratories at SECO Tools inFagersta,Sweden.

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