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913 Uppsatser om Leaching tests - Sida 1 av 61

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.

"Man får liksom inte bli slav under nationella prov" : en undersökning om lärares reflektioner kring de nationella proven i årskurs 3

Since the beginning of 1940 there have been externally developed tests in Sweden. Their appearances have changed over the years together with the cognitive approach. Nowadays, this kind of tests is going by the name of the national tests, which was introduced in the year of 1994. When the Swedish National Agency for Education received the assignment to develop new purposes and national tests to the third grade students, debate took a bounce. The matter was well discussed; national tests in third grade or not?The national tests thus far carried out four rounds in the third grade and the purpose of my study was to find out how teachers are reasoning about the tests.

Phosphorus in agricultural soils around the Baltic Sea : comparisons of different laboratory methods as indices for phosphorus leaching to waters

Eutrophication of the Baltic Sea is a serious problem. A major contributing factor is diffuse losses of phosphorus (P) from agricultural land in surrounding countries. In order to estimate P losses, environmental monitoring of small agriculture-dominated catchments is being carried out in most of these countries. Evaluation of the risk of P leaching to waters is usually based on chemical tests originally developed to quantify the amount of soil P available for plant production. The tests are performed in different ways in the different countries and a number of different extraction agents are in use.

Nationella prov i årskurs 5 : En studie om hur lärare påverkas av proven i sin planering

National tests has been carried out in fifth grade since 1996. Spring 2011 is the first year since the start, when it is no longer mandatory for Swedish schools to carry out the tests in fifth grade. Instead the tests will be moved to sixth grade, starting in spring 2012. This thesis investigates what effects the national tests has got on the teachers planning, but also what attitude the educators have to the tests. To solve the subject, teachers that are active in fifth grade and have recently carried out nationel tests in their class, were interviewed.

Utvärdering och jämförelse av olika fälttester för fotbollsspelare

Different field tests are currently used in a wide extent in different levels of soccer teams. To be able to assess the players? physiological status the tests must have high validity, reliability and external validity. Many different tests have been developt, but currently only five of these tests are most commonly used: Yo-Yo intermittent recovery test (YIRT), Yo-Yo intermittent endurance test (YIET), Multi-sprint-test, Beep-test and Cooper-test. Presently there is no definitive conclusion regarding which of these tests is most suitable for soccer players.

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.

Konditionstester i rehabiliteringssammanhang : - En litteraturöversikt

During the past few years there has been an observed decrease in physical fitness within different patient groups. As a part of the rehabilitating physiotherapy treatment it is important to acknowledge the physical condition of the patient. Physical fitness testing might be difficult due to physical limitations within different patient groups. A broad range of exercise tests is therefore of importance in clinical practice. The aim of this overview was to describe exercise tests used in rehabilitation contexts, and to define areas of use and restrictions.

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.

Med avseende på likvärdig betygsättning? : Aktörers tankar om och erfarenheter av de nationella ämnesproven

This essay aims to study how national tests in the ninth grade are being viewed upon in the Swedish school system. What are the affected people?s thoughts regarding its field of application? For further information about this matter, three different sub studies have taken place. In the first sub study, literature from The Swedish National Agency for Education (SNAE) has been studied and compared to other researches. In the second sub study, pupils who took part in the national tests during the previous year answered a survey about their experiences working with the tests.

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.

Bedömning av teori och praktik : En jämförelse mellan teoretiska prov och nationella kursmål i ämnet idrott och hälsa A

A significant amount of a teacher?s work consists of evaluation and marking of the students, which involves a great responsibility. This essay put the teacher?s evaluation of the students in focus. Today?s course Idrott och hälsa A, at the upper secondary school level, consists of 100 points and all students take this course apart from students attending apprentice programs.

Utformning av kylkanaler och spånrum på superturbofräsar

This thesis describes how the chip space and coolant channels are designed in today?s mills, the ideas behind the design and what is considered to be the best method of cooling. It contains ideas on how the chip space can be simplified. It contains several concepts on how the cooling could be designed for better efficiency and manufacturability. There are also suggestions on how the cooling could be stopped when the cutter isn?t cutting.

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