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139 Uppsatser om Microbial leakage - Sida 8 av 10
Fem-studie av rörelser i planet mellan bakaxelbrygga ADA1100 och centralväxelhuslock R780
This thesis has been performed at Scania CV AB Technical Centre in Södertälje and its aim hasbeen to study the causes and effects of deformations in the interface between the rear axlehousing ADA1100 and the central gear house R780 during operation. Design changes that wouldincrease the sealing capability of the studied interface are also suggested. Finite element (FE)and CAD software have been the primary tools in this study.Finite element (FE) simulations are used in the industry to predict and develop engineeringdesigns. The main motive for FE simulations has traditionally been to identify weak spots in thedesign, regarding high tensions and large deformations.The FE model is an aggregation of submodels and interface models that represents the rear axlehousing, suspension, central gear, central gear housing, wheels, bolts and weldings, and theirinteractions. The submodels have different material properties and they are connected withcontact interface models.Boundary conditions are defined on the bushings in front of the rear axle and on the air bellowsbehind the rear axle.
Energieffektivisering i ett verkstadsföretag : En analys av energibesparande åtgärder samt uppvärmnings- och kylsystems driftkostnader och koldioxidutsläpp
The energy use in a workshop company has been examined in this work in order to find areas for energy efficiency improvement. The combined oil and electricity heating in the company were compared with other alternative heating systems including cooling of the premises in following combinations:Ground source heat pump for heating and coolingDistrict heating and absorption coolingDistrict heating and low temperate surface water coolingEnergy use, operation costs and carbon dioxide emissions were calculated for the current heating systems and the three alternatives including cooling. The ground source heat pump for heating and cooling decreases bought energy with 34 MWh annually compared to current heating only. The district heating and low temperate surface water cooling has the largest reduction of operation cost and carbon dioxide. The operation cost decreases with 42 kSEK and the carbon dioxide with 43 metric ton CO2 annually.
Produktutveckling av koncept för isbanesystem
Today most ice rinks in Sweden use secondary refrigeration systems with a solution of calcium chloride and water as secondary refrigerant. Due to the large amount of energy such a system uses more efficient systems would be desired.An earlier study concluded in the possibilities of using carbon dioxide as secondary refrigerant with copper tubes as the loops in the ice rink. Since then 3 ice rink refrigeration systems has been built with carbon dioxide in copper tubes. Excluding the ones being direct involved in those projects there is still very little knowledge about how these system works. This study has been made primarily with the aim of adding to the knowledge concerning availability and cost and secondary to look at possibilities for improvement.A comparison between systems with carbon dioxide, calcium chloride respective ammonium solved in water has been made by using Decision Matrix.
Påverkan av probiotika på kariesbildande bakterier in vivo
Abstract
Cavities used to be a very common problem but over time humans have learned to take care of their teeth. However, there are still many who have problems. This problem is due to microorganisms and in particular the various streptococci and lactobacilli producing acids which loosens up the enamel on teeth. These bacteria can be found at various places in the mouth and saliva. Besides being a discomfort it can be a major problems and the damaged tooth needs to be removed or make a dental filling.
The aim of the study was to see how intake of probiotic tablets containing Lactobacillus reuteri PTA ATCC 5289 and Lactobacillus reuteri DSM 17938 affects the levels of oral Streptococcus mutans and lactobacilli over a three-week period.
Kronisk mitralisinsufficiens hos hund : samband mellan graden av klaffinsufficiens och det arteriella blodtrycket
Myxomatous mitral valve disease is a common disease in older dogs of small- to medium-size breeds. The mitral valve, and less commonly the tricuspid valve may be affected which causes them to leak blood from the ventricle to the atrium of the heart during systole. With increasing severity of mitral valve leakage the forward stroke volume ejected into the aorta decreases, which may lead to an increase in blood pressure in the pulmonary vein resulting in pulmonary edema. A decrease in cardiac output may lead to a decrease in blood pressure, but the body may respond in order to normalize the blood pressure. Franzén showed in 2007 that the systolic blood pressure was increased in dogs with severe mitral insufficiency.
Emotionella sprickor och utbrott - i en sorg
Intangible feelings of sorrow and grief, caused by events like separation, death, loss and trauma, all leave some kind of traces in us and they play an important role in our development. The individualistic society here in Sweden has shaped us to keep our feelings inside and at bay; since our childhood we have learnt that showing emotions like tears, sorrow and sadness are signs of weakness and can make others and yourself feel uncomfortable. With the starting point from my own experience and understanding of how we can deal and handle grief, I take a closer look on how jewelry, objects and rituals can be of importance in a grieving process and our lack of visual outer display of grief in today?s society. Through Sara Ahmeds theory I found a new possible way of understanding emotions and how they shape us.
Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser
Most of the saw and pulp industries have stored wood nearby their production, the main
reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality.
One drawback of wet storage of wood is the leaching of chemical substances into the
surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and
organic substances. These substances can cause problems for the surrounding environment.
The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.
Undersökning av deponerat ferrokromstoft : Utvärdering av ny behandlingsmetod
The production of ferrochromium alloys at Vargön Alloys AB contributes to formation of unwanted ferrochromium dust, which contains toxic Cr(VI). The dust is since summer 2005 treated with an iron-sulphate solution to reduce Cr(VI) to the non-toxic Cr(III). A year later the treatment technique was improved and disposal occurs in cells on the landfill. The cells can be up to 300 m3 and the edges can be made out of fro example concrete. Tests are conducted on the treated dust when it is disposed.
Planering av robotstall på Gästgivaregården Blacksta
This work has been done to develop a plan for a future dairy barn at theGästgivaregården and to show the space needed for cows and replacement heifers. Itwould also show the storage that will be needed. The design was largely based on resultsfrom studies on six different farms, but also the facts that are taken from research papersand articles in order to compare theory with practice. Because some farms only whereinterviewed by phone I have used a query form to obtain comparable resultes.The aim is to build a new barn with Automatic milking. I've drawn a milking stable for120 milking cow and replacement heifers with the capability to house up to 140 milkingcows if the farm would expand in the future.Calculations of feed amounts and space requirements have been made to see how manyhectares are needed to supply the cows and replacement heifers with feed and to knowabout what size of storage space is required.The investigations made in this writing are to answer questions about the AMS-unit`sposition and how to best maintain a good health status in the herd.
Materialegenskaper och dimensioneringsmetodik för vattenledningar : En sammanställning av de material som förekommer i Norrvattens ledningsnät samt dimensioneringsverktyg för plastledningar
Detta examensarbete har genomförts med anledning av att Norrvatten har önskemål om att få en rapport om de material som används i deras vattenledningsnät med fokus på typiska skador kopplade till ett specifikt material eller tillverkningsmetod. Det har framkommit indikationer om att kunskapen om rörmaterial och dess egenskaper med tiden har försämrats då den äldre generationens projektörer efterlämnat en kunskapslucka efter sig.Syftet med rapporten är att ge en god överblick av materialen i Norrvattens ledningsnät. Det krävs kunskap om materialen för att analysera sambandet mellan läckningsstatistik och materialets egenskaper.Informationshalten varierar mellan de olika materialen. Detta beror framförallt på materialets uppbyggnad och svårighetshalten att redovisa en klar och rättvis bild över dem. Materialen och dess information är uppdelade i kapitel för att underlätta för läsaren att på ett enkelt sätt förstå sammanhangen.Ett annat viktigt kapitel i denna rapport är beskrivningen över de anläggningsmetoder som valdes att tas med, dels markförlagda ledningar men också två schaktfria metoder vilka är infodring och rörspräckning.
Inverkan av torrsubstanshalt och temperatur på kompostens syrabildning :
Composting is a process in which organic matter is mineralized by microorganisms. In January 2005 landfilling of organic waste was prohibited in Sweden. With this prohibition composting has become an important alternative to handle the produced organic wastes. One problem with continuous small-scale composting is the production of organic acids that will inhibit a further composting process. The aim of these theses was to study what effects temperature and dry matter content had on the production of organics acids, and what effect the organic acids had on the mineralisation of the substrate as well as the stability during storage of the product.
Förbättrad omvårdnad med sårprodukt av mjölksyrabakterier och honung, för hästar med muggliknande sår
Wound care of the horse?s distal part of the leg is challenging. Due to that distal limb wounds are easily enlarged, infected and generally heal slower than wounds on the body of the horse, the need for improved wound nursing arise. One way of improving wound nursing is to evaluate new ways of healing treatment. In this study, evaluation was made of a new product consisting of lactic acid bacteria and honey.
Flygplansavisningens miljöpåverkan vid svenska flygplatser
The aim of this thesis was to answer a number of questions about the environmental consequences of aircraft de-icing. A further aim was to suggest how the environmental consequences due to the release of de-icing fluids can be measured and reduced.The main impact of the aircraft de-icing on the environment is due to the large oxygen demand for the degradation of glycol based de-icing fluids which are released in the environment. The effect of the increase in oxygen demand depends on where the degradation occurs in the ecosystem. In a sensitive ecosystem, the large demand of oxygen could provide an anaerobic environment which would be harmful for many types of organisms.In order to reduce the negative effects of the applied de-icing fluid, there is some type of collection system at every regular airport in Sweden. The methods of collection can be divided into two general groups, hydrological isolation or vacuum sweeper trucks.
Prefabricerade Passivhus
European Union has made a new decision that all new built houses by 2020 shallbe near-zero energy houses. Boverket?s definition of near-zero energy housesintends buildings with good energy performance in which a proportion of theamount of energy that must be added to the building is made of renewable energy.Passive House is a set of requirements from FEBY designed to build energyefficient buildings. This is achieved by reducing loss of heat through the buildingenvelope and to take advantage of the passive heat from solar radiation,installation and heat sources like people living in the house.This project has been made with help of Anebyhus and one of their model houseshave been examined from the report?s issues, including Anebyhus?s energyperformance, requirements for the manufacturing and assembly, how theenvelope must be improved to fulfill the requirements for the Passive House andwhat energy calculation programs are available on the market.The report aims to provide solutions for energy efficient houses that are adaptedfor production of house building.Two visits to Anebyhus has been done to study their manufacture and assemblyof building elements.
Mikrobiella hot mot nordiskt dricksvatten : En studie av mikrobiella föroreningar i dricksvatten i Norden samt en utvärdering av olika reningsprocesser
Den största akuta risken inom dricksvattenförsörjningen är vattenburen smittspridning. Dricksvattenrelaterad smittspridning förekommer i störst utsträckning i utvecklingsländer med dåliga sanitära förhållanden. Under 2000-talet har de nordiska länderna drabbats av flertalet dricksvattenburna sjukdomsutbrott vilket har lett till att mikrobiella föroreningar uppmärksammats som ett problem även i Norden. För att säkerställa att det dricksvatten som distribueras är av god mikrobiologisk kvalitet krävs att säkerhetsbarriärerna i vattenverket är tillräckligt effektiva för alla typer av mikrobiella föroreningar. Vissa mikroorganismer har uppmärksammats som mer tåliga mot olika desinfektionsmetoder, till exempel klorering, än vad som tidigare varit känt.