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477 Uppsatser om Heavy metal - Sida 5 av 32
Sedimentprovtagning av dagvattendammar som ett alternativ till flödesproportionell vattenprovtagning
Stormwater run-off from surfaces such as roads or rooftops is often polluted with Heavy metals and nutrients. Many of these substances can cause great damage in biota if they end up in the recipient. In Sweden constructed wetlands and ponds for treatment of stormwater are frequently used, since research has shown that these treatment ponds are reducing stormwater pollution considerably to a low cost. The knowledge of these pollutant removal mechanisms and how follow-up and assessment of the ponds should be performed is still limited.To determine the pollutant removal efficiency of the stormwater ponds it is recommended that flow-weighted water samples are collected from both the inflow and the outflow of the pond. This method demands considerable resources of time and money for installations and analysis.
Reglering av matarsystem vid höghastighetskapning
Today small metal parts are mass-produced as for example rollers in cylinder bearings. At high velocity cutting the metal is cut with a great force in a scissor-like device. Both precision and repeatability is important to be able to guarantee good quality, but from an economical point of view it is also important to keep a great manufacturing capacity. The part of the process that is most time consuming is when the metal bar, that is about to be cut, is fed to the right position. Therefore it is interesting to examine if the time used for positioning can be reduced.
Tillverkning av mikronålar för medicinsk tillämpning
Transdermal drug delivery, besides painfulinjections with syringes, has long been associatedwith small size particle pharmaceuticals, which candiffuse through the skin. This method of drugadministration has only been applicable on a smallnumber of drugs, where active molecules are smalland delivery time should or can be long.Other drug delivery options are oral administrationand injection with hypodermic needles (ordinaryhospital syringes). In oral administration thestomach and liver tend to dissolve the drug and theeffect becomes more difficult to anticipate, anddrug delivery rates difficult to control. Hypodermicneedles are used as a mean of drug injectiondirectly into the bloodstream. This method ispainful and risks infection due to tissue damageand skin penetration.One way to get a painless non-damaging techniquewith high delivery rate that still can delivery largemolecules is to manufacture an array of microscopichollow needles and equip them with a pumping unitthat delivers the correct amount of drugs.This thesis shows the technique and possibility ofmanufacture micromachined needles using low costtechniques of Ion Track Technology (radiation ofheavy ions creates porous materials), electrolessdeposition (non-current activated wet chemistrymethod of depositing metal) and electroplating.
Maskinduglighet på planlaserskärare
Lars Höglund AB is one of Scandinavia?s most qualified manufacturers of sheet metal products and provides custom designed products of very detailed precision. One of the main methods of manufacturing is laser cutting. When Lars Höglund AB signed up a new customer, with high demands in tolerances for the products, Lars Höglund AB thought it would be necessary to know the capability of the laser cutting machine. Also the process of how to retrieve this capability was interesting. The capability will be researched for the following elements: Cutting right angles in squares with a corner radius of 1 mmCutting corners which are not right angleCutting of circles with constant radius Measurements were made on 150 pieces of sheet metal details, which had been cut out by the machine. The data from the measurements where later used to study the capability.
Grundvattnets geokemi vid Gladhammars gruvfält, Västervik. Effekter av äldre tiders kobolt- och kopparbrytning
The municipality of Västervik, with support from Envipro Miljöteknik AB, is carrying out a main study of the minefields at Gladhammar. Mining of iron, copper and cobalt under different periods from the 16th century until the end of the 19th century has led to discharges of metals to the lakes situated downstream. The aim of the main study is to investigate the possibilities to reduce the environmental load on the surrounding ground and water caused by Heavy metals from the mine. The present report is a part of the main study. The aim of the work is to investigate the geochemistry of the groundwater.
Förutsättningarna för ett parallellt generation IV system vid svensk nybyggnation av kärnkraft.
A new build in the Swedish nuclear power system would entail increased re-quirements for the proposed repository, which is adapted after the reactors of today. With a fast reactor, capable of burning nuclear waste, operating in parallel with the light water reactors, the increased requirements on the repository could be reduced.In this thesis, simulations of a light water reactor and a fast reactor have been performed by using the Monte Carlo code Serpent to investigate the changes in the fuel inventory. The light water reactor in the study is a boiling water reactor and the fast reactor of the type sodium-cooled fast reactor and they have been used for three different operation scenarios.By studying the fuel composition and the results from the simulations of the three scenarios conclusions can be drawn. Conclusions regarding the change of the fuel inventory and decay heat in Clab as well as the interim storage facility and in the repository. Depending on the operation alternative the changes dif-fered significantly and especially regarding the mass of burned actinides for different fuels in the fast reactor.The lowest increase of fuel assemblies was meet when using 50 years old fuel with 20MWd/kg U burnout and 2,0 % enrichment for start up of the fast reactor and 30 years old fuel assemblies with 50MWd/kg U burnout and 4,7 % enrichment for the further operation of the reactor.The increase of the number of fuel assemblies was 3174, which is equivalent to 641tons of Heavy metal.
Arkitektur i Mayariket : en jämförelse mellan Palenque och Tikal
The classical age cities of Palenque and Tikal where ones great Mayan bastions with extraordinary architecture. This architecture still fascinates modern archaeologies and historians alike. Still much of the architecture in the Mayan cities had the same style and function, but could diverse from town to town. This is the case of Palenque and Tikal. They share much of their buildings like temples, palaces and ball courts.
Jordbearbetningsstrategier på hösten inför vårsådd på tyngre lerjordar :
It is important for today?s farmers to minimize the costs for crop establishment, because
of decreased prices and support from the EU. Farmers, who plow in autumn on heavy
clay soil, often do some kind of tillage in autumn to get better soil structure before
spring seeding. This is especially important when growing small seed crop, e.g. sugar
beet and oil plants.
Miljöteknisk undersökning enligt MIFO : en studie på fastigheten Bodsjölandet 1:14 avseende den nedlagda tjärfabriken i Grötingen
During 40 years of industrial production, from the end of the 1890?s until the end of 1930?s, coal and wood distillation products were manufactured in AB Carbo?s tar factory along the River Gimån in Grötingen, in the county of Jämtland, Sweden. In accordance with the Swedish Environmental Protection Agency?s Methods for Inventories of contaminated sites, MIFO, the site in Grötingen has been identified as a potentially contaminated site. In order to determine whether toxic substances pose a threat to human health and ecological systems in the area, there was a need to investigate the presence of contaminants, their levels and potential for migration.
Effects of biogas residues on respiration and denitrification in arable soil : evaluation of methods, microbial activity and agronomic implications
Agricultural soils constitute the base in human food production and soil content of organic matter and plant nutrients together with soil microbial activity are all important parameters for high crop yield of good quality. These parameters are dependant on proper fertilization.Anaerobic digestion of organic wastes for biogas production generates a liquid residue called biogas residue (BR). It contains organic material and plant nutrients which makes ita potential fertilizer for arable cropping. However, it also contains Heavy metals and toxic organic compounds and it is therefore in need of evaluation before usage.Microbial tests were performed aiming to evaluate the agronomic traits of four different BR and to find a viable procedure for evaluating slurry fertilizers. Two experiments where soil respiration and soil potential denitrification activity (PDA) was measured at fertilizer addition were performed.
Optimering av maskinprocess
Since 2007, I´ve been working in the steel industry in a place called ?SSAB?. That?s why itseemed right to contact them for this thesis.The SSAB concern is global, but SSAB Sweden involves raw steel producing in Luleå, heavyplate producing in Oxelösund, and sheet metal producing in Borlänge..
Metod för val av sunda yt-material
Since 2007, I´ve been working in the steel industry in a place called ?SSAB?. That?s why itseemed right to contact them for this thesis.The SSAB concern is global, but SSAB Sweden involves raw steel producing in Luleå, heavyplate producing in Oxelösund, and sheet metal producing in Borlänge..
Återvinning av näringsämnen från hushållsspillvatten med omvänd osmos
Hammarby Sjöstad is a new district in Stockholm with high environmental standard. Stockholm Water Company evaluates a local wastewater treatment plant with cutting edge technology. The first step is an experimental treatment plant (Sjöstadsverket) with four parallel lines of treatment, each with a capacity to treat wastewater from 150 persons. Within the membrane technology subproject the possibility of using reverse osmosis (usually called RO) to regain nutrients is examined.Reverse osmosis separates the incoming water in a clean permeate and a concentrate that, as the name indicates, is a more concentrated version of the incoming water. Using this method in wastewater treatment, a solution high in nutrients can be obtained without the use of chemical precipitation agent and with no production of sludge.
Musikfestivaler som turistiskt dragplåster : en fallstudie på Sweden Rock Festival
Lately, more and more music festivals have emerged in Sweden. People?s desire and need to visit these events only seems to increase. Cultural tourism and music tourism has developed into a significant and important part of the experience industry and it employs more and more people within the tourism industry. The purpose of this paper is to investigate which effects this can have on the local community.
Låsning till spolkarslock
Since 2007, I´ve been working in the steel industry in a place called ?SSAB?. That?s why itseemed right to contact them for this thesis.The SSAB concern is global, but SSAB Sweden involves raw steel producing in Luleå, heavyplate producing in Oxelösund, and sheet metal producing in Borlänge..