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46 Uppsatser om Conductivity - Sida 3 av 4
Brunnsviken : Utvärdering av åtgärder för förbättrad vattenkvalitet
Periods of hypoxia are a recurring issue in Brunnsviken. Main factors that trigger hypoxia in Brunnsviken are eutrophication due to anthropogenic emission of nutrients, stratification in the water column due to salinity and temperature differences that prevents mixing and a sill inlet that prevents water exchange. As an attempt to improve the oxygen levels, bottom water is pumped from Brunnsviken causing aerated surface water to flow back into the basin. The objective of this Master?s thesis was to study the change in dissolved oxygen levels due to pumping.
Avgränsning av tillrinningsområden till grundvattenmagasin : vilken information ger berggrundens överyta?
Delineation of recharge areas for aquifers is performed in the groundwater mapping process at the Swedish geological survey, SGU. This work is time consuming and performed manually. It is therefore desirable to develop a more general and repeatable method for defining recharge areas for aquifers.The purpose of this study was to investigate two other possible methods to delineate recharge areas for aquifers. The first method was to examine the possibility of using the topography of the bedrock to define the recharge areas for aquifers. To enable this, a method for generating the topography of the bedrock was developed.
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.
Järnets förekomst i grundvattnet i isälvsavlagringar i Dalarna : Bakgrundshalter och rörmaterialets inverkan vid grundvattenprovtagning
A study has been performed that investigates the variation of iron content in groundwater.The study was initiated by Midvatten AB, which noticed that the iron content in groundwater samples can vary greatly over small distances. The purpose of this study was to geochemically and geohydrologically determine the factors that influence the content of iron and manganese in groundwater from a selection of eskers in Dalarna, and determine how to best sample groundwater with the method used by Midvatten AB. An evaluation was made of how the vertical variation in soil material, water composition, pumping time and pipe material affects the content of iron in groundwater. Piper diagrams were used to study the relationship between the chemical composition of the groundwater and the content of iron and manganese in groundwater samples from the studied areas. The groundwater from the studied areas was then classified in the Piper diagrams, according to the content of the major ions.
Uppvärmd konstgräsplan : Beräkning av utnyttjningstid för en uppvärmd konstgräplan med alternativa rörplaceringar
For Skattkärr IF a turf field with warming has been projected to increase field?s utilization hours and to have a longer period for athletes to perform their activities outdoors. The technique chosen to heat the plan is a type of a geothermal heating system without a heat pump. The brine, which is water with 30% ethanol, collects heat from the borehole and discharges it to a coil in the field. There is at position 11 boreholes but it is planned to increase the number to 31, which is the design for the facility.
Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam
Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as a complexing agent for heavy metals and in this way increase their mobility.
Kemisk stabilisering av gruvavfall från Ljusnarsbergsfältet med mesakalk och avloppsslam : Chemical stabilization of mine waste with sewage sludge and calcium carbonate residues
Chemical stabilization of mine waste from Ljusnarsbergsfältet with sewage sludge and calcium carbonate residuesMine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolvedoxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as complexing agents for heavy metals and in this way increase their mobility.
Allanblackia stuhlmannii ? a tree under current domestication: what are the soil requirements?
Allanblackia is a genus of trees that grows in the rainforests of West, Central and Eastern Africa. Its big fruits contain seeds very rich in oil which has been used by
local communities for cooking and making soaps. The native stands are threatened by overexploitation and the demand for the oil is much greater than the supply.
Domestication programs, aiming at introducing the trees to small holder agroforestry systems, have been started for some of the species. The main aim of this study was to investigate the soil requirements of Allanblackia
stuhlmannii in terms of chemical and physical parameters, as revealed by the soil conditions in native stands. Another aim was to see if these varied along an altitudinal transect.
Hur påverkar gummigolv i grisningsboxen suggans liggtider, liggbeteende och hennes tid för att lägga sig?
In the farrowing pens the amount of bedding material and the quality of the concrete floor has a huge impact on both the sow and the piglets. In this study imbedding of
rubber flooring on the solid area in the farrowing pen was used to see if it had any effects on the sows lying behaviour when compared to concrete. Another important
aspect was to evaluate if the rubber floorings had a high enough durability to resist the normal wear in a farrowing pen. Concrete flooring is assumed to have a higher thermally
conductive effect then rubber which can affect the sow?s chance to cool down.
Fosforavskiljning och hydraulisk konduktivitet i markbaserade reningssystem ? Kornstorleksfördelningens betydelse
Fosforutsläpp kan leda till övergödning i vattenrecipienten om kritiska nivåer överskrids. De enskilda avloppen står idag för en relativt stor andel av Sveriges fosforutsläpp jämfört med de kommunala avloppen. Detta kan sättas i bakgrund av att staten, alltsedan 1970-talet, har lagt ner stora resurser på att reducera utsläppen hos kommunala avlopp, medan en motsvarande satsning på de enskilda avloppen uteblivit.Merparten av dagens enskilda avlopp utgörs av markbaserade reningssystem, det vill säga avloppslösningar där avloppsvattnet får passera genom markmaterial för att renas. Fosforreningen i markbaserade reningssystem har forskningshistoriskt sett inte varit en prioriterad fråga, vilket har lett till kunskapsbrist inom området. Naturvårdsverket har i och med miljöbalkens införande skärpt sina krav på fosforreningen hos enskilda avlopp.
Interaktionskvalitet - hur mäts det?
Den tekniska utvecklingen har lett till att massiva mängder av information sänds, i höga
hastigheter. Detta flöde måste vi lära oss att hantera. För att maximera nyttan av de nya
teknikerna och undkomma de problem som detta enorma informationsflöde bär med sig, bör
interaktionskvalitet studeras. Vi måste anpassa gränssnitt efter användaren eftersom denne
inte har möjlighet att anpassa sig till, och sortera i för stora informationsmängder. Vi måste
utveckla system som gör människan mer effektiv vid användande av gränssnitt.
För att anpassa gränssnitten efter användarens behov och begränsningar krävs kunskaper
om den mänskliga kognitionen.
Påverkan på Valboåsen från verksamheter inom Svedens industriområde samt närliggande områden : hot mot grundvattnets kvalitet och kvantitet?
The aim of this work was to find out what potential contaminants from roads, residential area and businesses within Svedens industrial area that can affect groundwater quality and quantity. Data collection was from SGU, VISS, internal material from Gävleborg county Administrative Board and Gävle municipality archive. GIS software ArcGIS was used to create the map images in the work.
The studied area is located approximately ten kilometers west of Gävle city and consists of the esker Valboåsen, which is a glacifluvial deposit that in its central parts consist of coarse material that is overlaid by sand, clay and silt. North of esker Valboåsen there are the river Gavleån which has an inflow to the groundwater in the esker. This inflow represents the largest part of the groundwater recharge.
Analys av juverhälsodata från kärnbesättningen Viken :
Nötcenter Viken is a Swedish nucleus herd for dairy cattle. The goal for the farm is to select suitable mothers for the next top generation of bulls. Today the selection for udder health is based on a pedigree index and phenotype data. The pedigree index is based on the cow?s father and grandfathers breeding values.
Textile Electronics -Screentryckta konduktiva ledningsbanor pa? textila material
Studien underso?ker mo?jligheten att anva?nda ledande partiklar besta?ende av silver- belagda kopparflingor, fo?r att tillverka konduktiva ledningsbanor pa? textilsubstrat. Syftet med denna studie har varit att tillverka de banorna med hja?lp av screentryck- teknik. Sammansa?ttningen av bela?ggningsformuleringen har en stor inverkan pa? den be- lagda textilen och de ledande egenskaperna.
Geokemisk undersökning vid Rävlidmyrgruvan, Västerbottens län : provtagning, analys och förslag till åtgärder
The mining industry, in terms of ore excavation and metal production, is and has been
important to the Swedish economy. In connection with the ore excavation process, large
amounts of partly sulphidic waste are produced. When the metal sulphides are exposed to air and water they are eventually oxidised, which leads to the formation of acidic water with high concentrations of metal cations and sulphate ions, so called Acid Mine Drainage
(AMD). This water may reach the nearest surroundings and cause negative environmental
effects. By covering the waste with soil or water, the oxidation process can be minimised.
At the Rävlidmyran mine in the county of Västerbotten open pit mining took place between
1951 and 1991.