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52 Uppsatser om Zinc alloy - Sida 1 av 4

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.

Varmsmidning av aluminiumlegering 6026 T9 : Warm forging of aluminum alloy 6026 T9

In this project forging of aluminum alloy Al 6026 T9 has been performed in the temperature range of 400 °C ? 470 °C. The alloy which was in the shape of a cylindrical billet was formed in a press with the aim of analyzing the effect of different forging temperatures and required press load for optimal die filling. The component?s dimensions were later measured and compared to a reference piece.

Elektrolytisk reduktion av zink vid reningsprocess

When cylinders for motor saws are manufactured there are high demands on the cylinders strength and wearing qualities. Aluminum is a material with low density and is used by Husqvarna AB for their motor saw cylinders. The aluminum is strengthening with nickel that is attached to the cylinders through electrolysis. When aluminum is in contact with oxygen a film of oxide is formed. To eliminate the oxide and to prevent formation of new oxide zinc is used.

Rostfria stålkonstruktioner och rostskyddsbehandling av stålkonstruktioner enligt Eurocode

Steel is an excellent material to build with, but consideration must be given to the fact that unprotected steel corrodes, rusts, therefore, as a rule, the steel must be protected in some way. This can be done by reducing the tendency of the steel to corrode by using stainless steel or by treating the steel with a protection method. The two most common methods of protection are corrosion protection paint and zinc coating. To determine the method, the corrosive category must first be evaluated and this is done in accordance to EN ISO 12944-2:1998.Stainless steel is available in many varieties but only some of them have properties that make them suitable for use as construction steels. There are many factors to be considered in the design of stainless steel to prevent corrosion from occurring.

Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

Spårning av miljöstörande ämnen i Uppsala stads spillvattennät

To the sewer systems households, industries and other activities are connected. The wastewater is collected at treatment plants where a nutritious sludge is produced. The sludge does not only contain nutrients, but also hazardous substances originating from different activities in society. To reduce the flow of hazardous substances to treatment plants and to create a sustainable recycling of plant nutrients the Swedish Water & Wastewater Association has developed the certificate system REVAQ. This certificate requires a good quality of the sludge but also that the treatment plants maps the origin of the unwanted substances.

Riskbedömning vid Saltvikens kopparverk

AbstractAt Saltvikens copperindustry, which is located in the municipality of Oskarshamn, copper was refined from sulphiteore some hundred years ago. The ore underwent several steps in the process before the final product was received. These steps all had an influence on the environment through discharge of heavy metals. The area where the copper industry was located is today considered to be of specific national interest due to its valuable nature and cultural values, as well as its value for recreational outdoor activities. Therefore, it is important to determine the present level of contamination and if any transport of contaminants have occurred, and to identify the risks that are associated with the site both at present and in a longer time perspective.Thirtynine soil samples and 16 sediment samples have been analyzed.

The legacy of the mill : a metal polluted forest soil in Gusum

Soils in a metal contaminated site on Stångberget in Gusum in southeastSweden were investigated and compared to relatively unaffected soils a fewkilometres away. Pollution came from historical release of untreated flue gasesfrom a brass mill. The objective was to find information on how high the metalconcentrations are, if metals from the polluted soil affect the surroundings andif the metal contamination affects the microbial community. The soil wasinvestigated using several different methods, such as field XRF measurements,chemical analysis of metal, carbon and nitrogen content, pH, acid neutralizingcapacity, texture, soil depth, field leach tests, sequential extraction and microbialfunctional profiles. The study showed that copper and zinc concentrationswere above Swedish Environmental Protection Agency guidelines for lesssensitive land use on the entire investigated area.

Kontroll av zinkskikt på monterat räckesmaterial

Kontroll av zinkskikt på monterat räckesmaterial som görs ute i fält saknar en fastställd metod. Zinktjockleken har ett minimum tjocklekskrav enligt den svenska standarden ISO 1461:2009, som bestäms av dimensionen på ståldetaljens tjocklek. Trafikverket begär att med hjälp av detta examensarbete kunna begränsa antal mätningar på plats, då kan det ta allt för mycket tid och arbetsresurser i fall det skulle behövas kontroll av väg-och bro räckesanläggningar från beställaren.Sannolikhetsläran och stickprov i statistik hjälper oss att begränsa antalet mätningarna på skyddsanordningarna som görs ute i fält. Med hjälp av normalfördelning kommer man fram till den efter strävade metoden, som med en rimlig arbetsinsats ger en rättvisbild av skikttjockleken på monterat räckesmaterial.Vid variation av varmförzinkaren på vägräckesanläggningar undersöker man varje leverantörs räckesdel för sig, alltså man mäter zinktjockleken på en varmförzikare för sig, kontrollerar zinkskiktstjockleken på de och tar slutsatser sedan går man vidare till nästa tillverkare. Om vägräckena är mindre än 30 stycken mäter man zinktjockleken på respektive anläggning.För beräkning av zinkskiktstjockleken på monterad räckesmaterial börjar man med 30 mätningar och användning av den centrala gränsvärde satsen för att approximera till normalfördelning och analysera resultatet.Det slutliga resultatet av examensarbetet är ett Excelprogram med inmatade formler.

Växters förmåga att ackumulera metaller : Vass, bredkaveldun och gäddnate i Bergviks dagvattendamm

AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.

Metaller i dagvatten - Effekter i recipient : En analys av koppar, kdamium och zink i dagvatten från en parkering i Halmstad, Sverige

When stormwater occurs near human activity the water gets polluted. The purity and composition vary widely depending on the types of activities in the area, the type of surface the water comes in contact with, precipitation and many more parameters. It has long been known that stormwater quality can affect both human health and the environment as stormwater is a major contributor to pollution of receiving waters.A human activity that has an impact on the environment in several different ways is traffic and stormwater is no exception. Airborne gases that react with precipitation, oil leaks and fuel systems that drops down on the ground, metals from brake linings and rubber particles from tire wear are some of the aspects you have to take into account when categorizing the relationship between traffic and polluted stormwater.In this project, stormwater samples from a parking lot in Halmstad, Sweden were collected and analyzed with an atomic spectrophotometer. The presence and relationship between copper, cadmium and zinc with different rainfall parameters have been studied.

Kateterrelaterade urinvägsinfektioner ? brist på effektiva preventioner ? En litteratursammanställning

Background: Urinary tract infections caused by indwelling urinary catheters causes unneccesay suffering among those it affects. These infections are also financially straining on the health care services. It is therefore of importance to gain knowledge about which evidence based preventive interventions that have the possibility to reduce the risk for bacteriuria and urinary tract infections among patients with indwelling urinary catheters. Aim: This study aimed to compile available knowledge concerning i) if silver alloy catheters does reduce bacteriuria in this patient group, ii) if aseptic catheterization does reduce bacteriuria in this patientgroup, iii) which routines for changing the urinary drainage bag reduces the risk of bacteriuria, iv) which routine genital hygenic care reduces the risk of bacteriuria? Method: Litterature was searched for in the data bases Cinahl, Medline and The Cochrane Library using the data bases? thesaurius combined with OR/AND.

Kateterrelaterade urinvägsinfektioner ? brist på effektiva preventioner ? En litteratursammanställning

Background: Urinary tract infections caused by indwelling urinary catheters causes unneccesay suffering among those it affects. These infections are also financially straining on the health care services. It is therefore of importance to gain knowledge about which evidence based preventive interventions that have the possibility to reduce the risk for bacteriuria and urinary tract infections among patients with indwelling urinary catheters. Aim: This study aimed to compile available knowledge concerning i) if silver alloy catheters does reduce bacteriuria in this patient group, ii) if aseptic catheterization does reduce bacteriuria in this patientgroup, iii) which routines for changing the urinary drainage bag reduces the risk of bacteriuria, iv) which routine genital hygenic care reduces the risk of bacteriuria? Method: Litterature was searched for in the data bases Cinahl, Medline and The Cochrane Library using the data bases? thesaurius combined with OR/AND.

Dietary intake of zinc and iron within the female population of two farming villages in the Red River Delta, Vietnam

In many developing countries, among them Vietnam, contamination of agricultural land is a major issue that has public health implications. A fast growing population, rapid urbanization and industrialization have led to air and water emissions of potentially toxic elements (PTEs), such as cadmium (Cd). Earlier studies have shown that individuals with low iron (Fe) and zinc (Zn) status absorb larger quantities of Cd than those of adequate nutritional status. The purpose of this study was to investigate and compare the Fe and Zn intake from the foods consumed by women (15-45 years) in selected households in two agricultural villag-es in the Red River delta in Vietnam. In one of the villages the residents were involved in metal (mainly Fe) recycling activity, whereas in the other village the residents had agricul-tural production as main source of income. Interviews, followed by food intake calcula-tions, were performed.

Prevention of catheter-associated urinary tract infection

AbstractBackground: After a while the usage of urinary catheters leads to UTI which for the patient means inconvenience, suffering and pain. Aim: The aim of this study was to illuminate how to prevent UTI from patients with indwelling catheter. Method: This study was a literature review in which the articles have been searched for in PubMed, Cinahl and ELIN@Kristianstad. Results: It is important for the nurse to clean the periutheral area before inserting the catheter, and has the knowledge of different cathetermaterials. Silver alloy-coated catheters reduces the rate of UTI.

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