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3315 Uppsatser om Leaching test - Sida 1 av 221

Laktester för riskbedömning av förorenad mark :

Using Leaching test is a way to get a picture of pollutants retention and leaching in a risk assessment on contaminated land. There are several different types of standardised Leaching tests today, where the natural leaching processes are speeded up to make it possible to predict the leaching of pollutants. These Leaching tests have been developed for waste and there are no specific guidelines on how to judge the results from the tests, when making a risk assessment on contaminated land. This work is an investigation on how to use Leaching test in this type of risk assessments. The strengths and weaknesses of the different types of tests are discussed. Depending on what type of information you want from your Leaching test, different types of tests are suitable.

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.

Möjligheter att minska kväveutlakningen genom att anpassa kvävegödslingen till variationer inom stråsädesfält

Due to excess precipitation that cause runoff, all soils in Sweden naturally leaches nitrogen.High leaching from arable land is an environmental problem when the runoff reacheswaters. In the international agreement, Baltic Sea Action Plan, the aim is to reduce therunoff of nutrients. Sweden has agreed to reduce its load of e.g. nitrogen to the Baltic Sea.One of the proposed measures is an increased use of site-specific N-fertilization, which hasbeen shown to increase nitrogen use efficiency and therefore also reduce the nitrogen runoff.Either yields are increased with the same total amount of nitrogen, or the total quantityof nitrogen is reduced with preserved yield levels, which is profitable for the farmers.The dynamics of nitrogen leaching differs between top dressing applications above orbelow the economical optimum. There is a consensus about a difference in the dynamics,but not about its magnitude.

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.

Kvävestatus och risk för nitrifikation i två avverkade skogsområden i Halland

Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of nitrate, since nitrate is easily transported through the soil.

Lakningsförsök med furubarksflis : en utredning om utsläpp av fenolföreningar samt metallsorption

The filters used today to purify water are often expensive and the need to find new filter materials is substantial. Studies of pine bark have shown that this is a material that may be used as an alternative to conventional filter materials, such as activated carbon. However, the study of pine bark has shown that a leakage of phenolic compounds may occur when using the material for water purification. Therefore, the purpose of this report is to investigate the release of phenols from pine bark, in order to evaluate the use of pine bark as a filter material. Another assignment is to investigate the amount of metals adsorbed by the filter material.

Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark

This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.

Kalkningens påverkan på fosforlöslighet : skakförsök baserade på två svenska långliggande kalk- och fosforgödslingsförsök

Eutrophication is an environmental problem that affects more than ten percent of Swedish lakes. Excess nutrients increase the growth of algae, and cause major problems in the ecosystem through oxygen-free bottoms, fish kills, and at worst dead bottoms. Agriculture accounts for 44% of human emissions of phosphorus to lakes and rivers. Leaching occurs of particle bound phosphorus and of dissolved phosphate. The amount of phosphate in the soil solution that may be leached is partly due to the prevailing pH in the soil solution. The purpose of this study was to investigate how the relationship between phosphate solubility and pH was affected by liming.

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.

En beskrivning av manuellt test : Svagheter och styrkor med och utan stöd avett testverktyg

Test is an area in system development. Test can be performed manually or automated. Test activities can be supported by Word documents and Excel sheets for documenting and executing test cases and as well for follow up, but there are also new test tools designed to support and facilitate the testing process and the activities of the test. This study has described manual test and identified strengths and weaknesses of manual testing with a testing tool called Microsoft Test Manager (MTM) and of manual testing using test cases and test log templates developed by the testers at Sogeti. The result that emerged from the problem and strength analysis and the analysis of literature studies and firsthand experiences (in terms of creating, documenting and executing test cases) addresses the issue of the following weaknesses and strengths.

Testbänk för luftlager

Test bench for air bearingsThis thesis work consisted of bringing forward and defining the test parameters relevant for a test bench and constructing a test bench that can test and verify the largest existing air bearings that are of use in Micronic Laser Systems AB machines. Because the knowledge about air bearings is limited it is thought that with the help of the test bench the knowledge would increase and in that way improve the air bearings.After learning more about air bearings and their purpose at Micronic Laser Systems AB, I started the concept phase for the test bench. For each part in the test bench I consulted my two tutors, Torbjörn Hedevärn and Johan Bergqvist, at Micronic Laser Systems AB. The final concepts where documented as 3D-modells in Solidworks and some of them have been tested in Solidworks FEM-program.The test bench is designed so that, with the help of a pneumatic cylinder, 25 kilo weights are placed on the air bearing to test its stiffness, damping and the pressure performance under its surface area. To test these parameters the test bench has to have a pressure meter, accelerometer and a microcator.

Användbarheten hos WNV: granskning av ett nytt icke-verbalt intelligenstest för barn

This paper investigates the usability of the intelligence test Wechsler Nonverbal Scale of Ability (WNV). Twenty four children in two different age-groups were tested with WNV, 10 children between ages 5 - 6, and 14 children between ages 9 - 10. The WNV turned out to be a useful test when some verbal communication was used in the test situation. This was especially apparent among the younger children, who needed extra verbal instructions and verbal support through the different subtests. The test also contained standardized verbal instructions for all ages.

Konduktivitet i vattendrag som indikator på sura sulfatjordar

Increasing attention is being given to acid sulphate soils wherever they occur. The problems that leaching sulphate soils gives with significant lowerings of pH and mobilization of heavy metals influence large spectra of our society from fisheries to agriculture to construction. Mapping these soils is consequently of great importance and the methods of doing this is very much lacking in function and precision. This study was therefore carried out to investigate whether conductivity in running water can be used as a simple instrument to identify acid sulphate soils in the catchment. 31 coastal streams in the county of Västerbotten were analyzed for different catchment properties such as occurence of marine sediments and basic water chemistry including conductivity and sulphate.

Svarar människor mer eller mindre socialt önskvärt beroende på hur de genomför ett personlighetstest?

A personality test is a useful tool in recruitment contexts. Studies have shown that participants distort their answers in a socially desirable manner. The purpose of this study was to investigate if people respond more or less socially desirable depending on how they rate themselves in a personality test, based on the "big five" personality dimensions.Eighty people, (40 women and 40 men), 19-42 years, (M= 24,1 SD= 3,76) rated themselves on a personality test. Group one, (20 women and 20 men) completed the test on paper. Group two, (20 women and 20 men) completed the test verbally.

Hur barn i årkurs 3 uppfattar syftet med Nationella provet

This is a study of the national test in 3rd grade. The national test is obligatory and is conducted in 5th and 9th grade, but since the spring of 2009 the tests also become mandatory in 3rd grade. The case study of this research is to find out how children in 3rd grade perceive the purpose of the national test. The survey should also clarify how students think and feel about the national test, and how they feel before the national test and after they have finished writing the test. Has the test positive or negative influence on children? The survey will also show how much teachers clarify what the significance of the national test is for the students.

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