The aim of the study was to investigate if methane emission in a constructed wetland changed in a diurnal pattern correlating to temperature, humidity or light conditions. The gas measurements were carried out with a static chamber technique. The wetland (in Nykvarn outside of Linköping, Sweden) takes care of wastewater to reduce the nitrogen loads. Measurements were carried out at three different occasions in the summer of 1998 on two sites in the wetland. One site was close to the inflow, inhabited by Lemnaceae, and another site was located further downstream inhabited by the emergent macrophyte Typha latifolia.

When rubber equipment in a milking system ages, physical and chemical deterioration occurs and cracks, crevices, as well as deposits of organic and inorganic material is formed on the surface. Bacterial colonization can accumulate, especially on ageing rubber equipment and if the cleaning procedure is not functioning properly. Formation of biofilm in milking equipment could in turn cause bacterial contamination of bulk tank milk. ATP bioluminescence is a fast and easy way to determine the hygienic status of a surface based on its ATP content, and results are given in relative light units (RLU). The method measures both bacterial contamination as well as residues from other organic material.

Bath has been a part of human history for a long time. Today bathing/swimming inmunicipal pools is for people of all ages and it is possible to take swimming courses,exercise or enjoy recreation. The municipal indoor pool of Hogdalen in Sweden wasbuild in the sixties and has had problems with high levels of heterotrophic bacteria. Thefacility has two larger pools, one adventure park for young kids, two smaller bath tubsand a jacuzzi. To improve water quality UV light and coal filter were installed inOctober 2009 to the already existing purification system.

This thesis work was made for Södra Cell Mörrums bruk in Blekinge. The purpose of the work was to develop a computer model in the simulation program Extend for the removal and balance of organic oxygen consuming substances, measured as COD (Chemical Oxygen Demand), in the new biological treatment plant in the mill. The plant produces two different pulp products, TCF- (Totally Chlorine Free) pulp and ECF- (Elementary Chlorine Free) pulp, for sale. The different bleaching procedures affect the characteristic of the wastewater and thus the effectiveness of the biological treatment plant.In the model that was developed the COD in the wastewater was divided into five different COD-fractions: soluble easily degradable (SS), soluble hardly degradable (SR), soluble inert (SI), particulate inert (XI) and particulate biomass (XB). To create the model FlowMac? was used as a base.

Fermented liquid feed is well known for its health promoting effects on piglets. High levels of lactic acid are desired in the feed together with low levels of acetic acid and certain biogenic amines. Limits for acetic acid have been suggested to be 30-40 mmol/kg to avoid a decreased palatability of the feed; however, few studies have been performed. The purpose of this trial was therefore to examine which levels of lactic acid and acetic acid that can be accepted in a fermented feed without affecting the feed intake and thus the weight gain of the pig. A total of 60 pigs (Yorkshire/ Hampshire) were used in a trial during two weeks, between 9-11 weeks of age.

This is a project about learning from an experience, about trying to have fun and not getting overwhelmed and draining your work. The thing that wraps this whole experience together is the making of a book. The purpose of making the book has been to bring two interests together, illustration and graphic design.The content of the book for this graduation project is written by Fredrik Mårtensson. His poetry tells about the unnatural state of the modern society. I have interpreted the poetry in six abstract illustrations that I made digitally, with the intent to maintain the feeling of something organic.The process of making this book is a lot about learning what it actually takes to finish it, about trying to tell something and a lot about experience practical work..

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.

This paper presents why and how teachers use newspaper articles in the classroom when they educate their pupils in chemistry, biology and nature science. All the teachers have worked over 20 years and are, when interviewed, at a Swedish gymnasium in Dalarna. I also have, in a small study, interviewed some of their pupils to get their view about teachers using news paper articles during lessons.The teacher?s use of newspaper articles in the classroom can be divided in different ways. They can use the articles to illustrate up to date links to everyday life.

The freshwater pearl mussel Margaritifera margaritifera is an endangered species. To survive, the young mussels demand a fairly coarse bottom material containing an appropriate quantity of organic substrate to survive without suffocating. In order to estimate if a bottom is suitable for juvenile mussels, samples of the sediment are needed. To obtain samples a sampling device called the Mulv collector has been developed within this project. Bottom samples were collected from 18 stations in 4 south Swedish streams, Vramsån, Kling-storpsbäcken, Brönnestadsån and Bräkneån.

Areal is one of the major players in the Swedish market for real estate brokerage of agricultural properties and related additional services. The purpose of this report is to give a better picture of the needs for additional services of property purchasers of Areal. Add-on services are the type of counseling you may need to achieve good economy on an agricultural property. Through a survey of property buyers of Areal information has been collected and compiled. A very good response rate was obtained and the material seemed reliable as it reflected the population in general.

Agriculture has to be performed in a sustainable way in order to sustain high yields and to support a globally growing population. Functional soil properties are fundamental for high yields and in order to achieve good soil conditions sustainable management is a key. Loss of soil organic material and increased soil acidity are problems associated with degradation of soils and hence less sustainable agriculture. In this thesis, the effect of different agricultural systems on soil organic matter, pH and yield was examined. The systems examined are a cereal system with straw removal or returning and a ley system, all with different nitrogen levels.

This thesis has been focused around the Diels Alder reaction with the goal to design an enzyme catalyzed reaction pathway. To achieve this goal computer aided enzyme design was utilized. Common traditional methods of computational chemistry (B3LYP, MP2) do not do well when calculating reaction barriers or even reaction energies for the Diels Alder reaction. New calcu- lation methods were developed and tested. This was the focus of the first part of the thesis, by choosing a small system, extensive and heavy calculations could be done with CBS-QB3.

The aim of this study was to investigate preschool teacher?s perceptions about the curriculum goal concerning simple chemical processes. The result was based on narratives received by a qualitative study and semi-structured interviews of six preschool teachers. The results of the study showed that preschool teachers perceive that they actually are working in a relatively small scale with simple chemical processes and they do not really know what simple chemical processes are, and do not feel very familiar with the subject. Water, dough, mud, paint and baking were the most common activities that were used when working towards the curricular goal. However, it was never explained to the children that it was simple chemical processes they were working with during the activities, neither was it discussed among colleagues because of the uncertainty about the concept.

Acidification is a central concept in the environmental debate. The effect of acidification of the soil is a matter of a decreasing amount of cations and thereby a decreasing ability to resist a supply of hydrogen ions to the soil. Acidification has gradually increased in the O horizon in Västerbotten over a 30-year period from the 1970th to the 1990th. The aim of this study was from inventories of The Swedish National Forest Soil Survey and The Swedish National Forest Inventory explain and quantify the acidification that has occurred in the O horizon of two regions in the north of Sweden. Data from SMHI, The Swedish Meteorological and Hydrological Institute, has also been used.

The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.