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281 Uppsatser om Metal contamination - Sida 10 av 19

Bakterietillväxt i strömedel till mjölkkor

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most bacteria need humidity and prefer a quite high water activity to be able to grow.

Tungmetaller i metabolismen hos värphöns och slaktkycklingar

Mussel meal is a potential source of protein, with a good composition of amino acids, for laying hens and broiler chickens, and may replace the use of fish meal in organic poultry production. Lead and cadmium are heavy metals which occur in the environment and can be accumulated in mussels. When poultry are exposed to heavy metals, the metals are absorbed in the small intestine and distributed in the body in the form of ions, complexes or bound to proteins. In poultry, lead accumulates in bone tissue, liver and kidneys, while cadmium accumulates in liver and kidneys. Generally very low concentrations of these heavy metals occur in muscles of broilers which have been exposed to feed contaminated with cadmium or lead.

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.

Utformning & placering av vädringskanaler i ett passivhus, drivet av naturliga krafter

A passive house in Norra Djurgårdsstaden drawn by Tengbom Arkitekter is going to be built. A shaft for airing is needed for a few apartments in the house.The airing shaft is designed for a few two room apartments in the house, which are not able to achieve satisfactory airing, as their outer walls are facing a single direction. The other apartments on the same floor are corner apartments. These apartments do not have the same difficulty with airing since they have their outer walls in different directions, with different pressures at the facades. The airflow in the airing shaft is supposed to be driven only by natural forces, by the sun. The purpose of natural driven forces is to achieve low energy consumption for the house.In this thesis, a design of the shaft for airing has been developed.Initially an open shaft for all apartments was analyzed.

Höjning av vattennivån i Mälaren : Ett hot mot Stockholms centrala delar vid en framtida klimatförändring?

In today?s World is climate change an important and hot topic. Climate scenarios for Sweden show a warmer climate, especially during the autumn, winter and spring. The same climate scenarios also show that the precipitation will increase during this part of the year, however, during the summer the opposite is expected to occur. The purpose of this essay is to examine how future climate change will affect Stockholm especially the expected increase in precipitation, which may lead to a rising level of the Lake Mälaren. During 2000/2001 was Stockholm hit by a flood. This flood nearly resulted in major consequences and showed that there were significant risks for the city of Stockholm and increasing precipitation will result in even more water in the drainage systems of Lake Mälaren. The results presented here show that it is important to increase the drainage capacity of Lake Mälaren in order to reduce the risks of flooding in the central parts of Stockholm.

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.

3D modelling of a Laser Welding Cell for movie presentation : making of the movie

This report describes a Bachelor thesis work in which a robotised laser welding cell has been modelled and simulated for the purpose of making a presentation movie. The report shows that the work has been concentrated on making the movie from the modelling phase through the recording of the movie and ending up with the editing of the final presentation movie. A pre-study was made prior the Bachelor thesis work. In the pre-study a literature study was conducted about measurement and calibration of a welding cell. Measurement of almost all equipment in the entire cell was also conducted in the pre-study.

Kraven på ägare till minireningsverk skiljer sig åt mellan olika kommuner

Discharge of inadequately treated waste water containing nutrients such as phosphorus and nitrogen as well as organic matter and bacteria is associated with a risk of eutrophication and contamination. The Swedish government has decided upon several Environmental Quality Objectives aiming to reduce the emissions of nutrients to water bodies.In Sweden, there are between 675 000 to 1 000 000 on-site sewage systems. Recent studies have shown that the function of small sewage treatment plants is in many cases insufficient. To prevent this regular service and supervision by a professional is needed. The focus of this study are small sewage treatment plants which use a technique where mechanical, chemical and/or biological reduction of pollutants is being used in the same facility to reduce nutrients in household wastewater.The aim of the study is to investigate how different municipalities ensure that small sewage treatment plants fulfill the requirements and reduce pollutants as efficient as the manufacturers claim.

SEM/EDS-analyser av föremål påträffade i Birka : En jämförande studie

The purpose of this paper was to identify the elements and the alloys that five objects found in Birka consist of and to examine whether there are any significant differences between the presumably imported and domestic objects. The material was analyzed using a scanning electron microscope (SEM) which was equipped with an energy dispersive X-ray spectrometer (EDS) in order to identify the elements that are present and the alloys that the objects are made of. Then the SEM results were compared with the results of previous analyzes that have been performed on finds from Birka in order to investigate how the objects differ in elemental composition and to find out if there are any significant differences between them. The results showed that the objects? content of the elements analyzed varies as the copper alloys the objects are made of.

Möjligheter att öka effektiviteten och det ekonomiska utfallet av barkhanteringen vid Seskarö sågverk :

The sludgebark and to a certain extent the bark were until a decade ago waste products without any economic value that were thrown away. A number of environmental laws and increcing energy prices have improved the prerequisites for increasing the use of these materials. At Seskarö sawmill they burn the sludgebark and a great deal of the bark in the sawmill furnace. The sludgebark has a number of disadvantages compared to bark during burning. The sludgebark is often wet which means the energy net from burning often gets low.

Demonstratortest av gassensor baserad på tryckt organisk elektronik och jonledande papper

Researchers at Karlstad University have developed a method for making paper ion conducting. The reasearchers want to test this technique in various applications and produce products that make use of the ion-conducting paper. Hopefully this will drive the development forward and result in new applications for the ion-conducting paper.This study was to test the possibility of manufacturing a gas sensor of conducting paper along with electrodes of conductive polymers printed on the paper. By comparing the paper sensor with an electrochemical cell in which the electrodes of conductive polymer replaces electrodes of metal and ion-conductive paper replaces the liquid electrolyte in the electrochemical cell, it was hoped that it would be possible to measure the oxidation and reduction reactions that a gas could introduce at the electrodes.It was shown that it is possible to measure a potential difference in the range of 0.3 V to 0.5 V between the electrodes when exposing an electrode to 100% oxygen. The reaction that takes place is relatively slow and the reaction rate is partly due to the distance between the electrodes.Since the sensor can measure oxidation and reduction reactions it is possible that, in further development of a sensor, the sensor can be made ??into a versatile sensor with more applications than gas measurement as there are many more ways to oxidize or reduce the electrodes than by exposure to oxygen.During the study there have been discussions and meetings held with various companies in the sensor industry to be able to specify what the market demands of a sensor made ??of paper and the requirements that must be placed on the sensor for it to be interesting for the companies..

Modell för dimensionering av AGV-system inom tung industri

Interest in the implementation of AGV-systems (Automated Guided Vehicle) has in recent decades increased. The reason is that it allows companies to perform reliably and secure internal transport while reducing the need of personnel. It is one of todays most advanced and complex material handling system that can independently make their own decisions regarding flow paths and traffic control. An AGV-system consists of transport units carrying cargo from point A to point B, and communicates using a computer.The purpose of this study is to develop a model on how to proceed in order to design an AGV system in heavy industry. The model is tested by a case study of a company in the metal industry to determine if the model works and gives the correct result.

Spelutveckling och lansering av applikation till Android

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Svensk vindkraft

Sweden's drinking water quality is considered to be high partly due to a high quality of the raw water and a well developed sewage infrastructure. Despite this, there is water contamination that could be prevented by installation of a sophisticated early warning system. Some of the major players in the production of drinking water have already invested in different types of early warning systems to ensure drinking water of high quality. There are various forms of early warning systems where automatic monitoring of E. Coli is an interesting alternative.

Tvärvetenskaplig undersökning av textil Broderiet från Tämta kyrka

There are several objects of age whose provenance and history has disappeared with time. The purpose of this thesis is to find out which analyzing methods that gives results and how the different methods can be combined and /or established in each other. The investigations centers around an embroidery, belonging to Tämta church, with unknown origin, use and age. The embroidery is long and narrow with applications in the form of dragons and eagles on a ground of velvet cloth. The dragons and eagles are covered with metal threads.

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