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1616 Uppsatser om Surface water - Sida 34 av 108

En utvärdering av de skogliga vattenplaneringsverktygen NPK+ och Blå målklassning med avseende på vattenkvalitet och vattenkemi

Intresset för vattenfrågor har ökat efter införandet av EU:s ramdirektiv för vatten (vattendirektivet, 2000/60/EG) och inneburit att vattenvård och hänsynstagande till vatten inom skogsbruket fått större fokus. Målet med vattendirektivet är att alla vatten inom EU (Europeiska Unionen) ska erhålla en god kemisk och ekologisk status innan år 2015 samt att ingen försämring får ske. Skogsbruket kan i vissa fall ha negativa effekter på vattenmiljöer. NPK+ och Blå målklassning är två skogliga vattenplaneringsverktyg som har utvecklats för att öka vattenhänsynen i skogen. Verktygen utgörs av ett inventeringsprotokoll som bedömer vattenmiljöns naturvärde (N), påverkan (P), känslighet för skogsbruk (K) samt plusvärden (+).

Tillagning i mikrovågsugn och dess effekt på livsmedel : En jämförelse med konventionell tillagning

Microwave is a time- efficient device for heating and reheating of foods. Despite the fact that its effects on foods have been evaluated during a long period of time, without any more negative effects shown compared to conventional cooking, one third of the Swedish population believes (in 2010) it accounts for a higher loss of nutrition. This literature review aim to compile studies regarding how food is affected by cooking in microwave, with respect to cooking losses, nutrition, secondary metabolites as well as sensory and textural aspects and compare it with conventional cooking. The compilation shows that different combination of effect (W), time and amount of water during microwave cooking have different effects on foods. The contents of proteins, vitamin B and carbohydrates are generally higher after microwave cooking, while anti-nutritional substances are affected much less during conventional cooking. This also depends on if it is of animal or non-animal origin. However, for the majority of nutrition values the differences are quite small.

Vindpark Vänern : Fundamentteknik och Logistik

An analysis of a specific application of anaerobic wastewater treatment at a pulp and board mill, Stora Enso Skoghall, was carried out. A literature study was done and effluent wastewater from CTMP pulp production was analyzed. The analysis consisted of a broad constituent analysis and an anaerobic treatment trial. Results from these test where used to calculate the treatment effectiveness and resulting energy potential at the mill.The literature study and constituent analysis showed that toxicity of the water to be treated, due to wood extractives and sulphur content, was of concern. Detoxification chemicals targeting these constituents where used in the anaerobic treatment trial.

Tillagning i mikrova?gsugn och dess effekt pa? livsmedel : en ja?mfo?relse med konventionell tillagning

Microwave is a time- efficient device for heating and reheating of foods. Despite the fact that its effects on foods have been evaluated during a long period of time, without any more negative effects shown compared to conventional cooking, one third of the Swedish population believes (in 2010) it accounts for a higher loss of nutrition. This literature review aim to compile studies regarding how food is affected by cooking in microwave, with respect to cooking losses, nutrition, secondary metabolites as well as sensory and textural aspects and compare it with conventional cooking. The compilation shows that different combination of effect (W), time and amount of water during microwave cooking have different effects on foods. The contents of proteins, vitamin B and carbohydrates are generally higher after microwave cooking, while anti-nutritional substances are affected much less during conventional cooking. This also depends on if it is of animal or non-animal origin. However, for the majority of nutrition values the differences are quite small.

NEDKYLNING HOS VANLIG B?NA, PHASEOLUS VULGARIS

Beans are a global source of plant-based protein, and in some countries, they constitute a primary source of protein intake. With ongoing climate change, including rising temperatures, it is necessary to adapt beans to ensure a reliable food supply. An important mechanism that many plants have, to cope with high temperatures, is cooling through transpiration. During transpiration, stomata open and release water vapor. Water molecules use heat energy from the leaf to convert into gas, thereby cooling the leaf.

Predicting spawning bed erosion and longevity : a case study in tributaries to river Vindelälven, northern Sweden

Timber floating operations in Scandinavia during the 19th and 20th centuries has contributed to severe negative impacts on riverine ecosystems. Increase in water velocity and lack of stream bed heterogeneity as a result of stream channelization lead to increased bed load transport. Since availability and recruitment of new suitable spawning substrate in Scandinavian watercourses is sparse, spawning habitats for salmonids has become a scarce commodity. Lately, increasingly more attention has been given to the recreation and improvement of brown trout (Salmo trutta) spawning habitats in restoration projects. While much of the research on spawning habitat has been focused on evaluation of the influence that the constructed spawning grounds have on fish populations, few studies have been conducted to evaluate the persistence of these constructions over time. I evaluate erosion of constructed spawning beds as an effect of sediment transport attributable to water discharge.

Avloppsvattenbehandling med membranbioreaktor : En jämförande systemanalys avseende exergi, miljöpåverkan samt återföring av närsalter

In the pilot plant at Hammarby Sjöstad, Sjöstadsverket, several new methods are tested in order to achieve a good use of resources. When a new technique is considered it is often the performance of the technique itself, under given conditions, that is evaluated. However, in order to evaluate the overall function the whole picture is needed. With a system analysis it becomes possible to make a comparison where all the positive aspects are put up against the negative ones, for the technique itself as well as its requirements. In this way the influence that minor components have on an entire system can be considered.This report presents a system analysis of an anaerobic membrane reactor (MBR) with a VSEP-membrane (Vibratory Shear Enhanced Process).

?Nu förstår jag!? : En undersökning om hur barns förståelse för vattnets väg till kranen kan utvecklas genom en pedagogisk aktivitet

Syftet med det här examensarbetet var att undersöka 3-5 åringars förmåga att utveckla sin förståelse för vattnets väg till kranen genom med en pedagogisk aktivitet. Genom den pedagogiska aktiviteten gavs barnen möjlighet att färdas genom vattensystemet med sina kroppar och sinnen, från sjön till kranen. För att kartlägga hur barnens förståelse utvecklats genomfördes kvalitativa intervjuer före och efter den pedagogiska aktiviteten.Jämförelsen mellan resultaten av förintervjuerna och uppföljningsintervjuerna pekar på en tydlig utveckling av barnens förståelse av vattnets väg till kranen, som ett tekniskt system. Flera av barnen utvecklade sin förståelse för att vårt hushållsvatten måste genomgå en reningsprocess, färdas genom olika komponenter i vattensystemet och rör innan det slutligen når kranen och kan förtäras..

Översvämningsrisker längs Funboån

Flooding events are no longer rare, floods occur all over the world. Accordingly, it is vital for the society and different authorities to work with flood mapping. To meet the goal of Uppsala kommun to map the risks of floods in Uppsala län, a map of the different areas around Funboån which are inside the area of risk for flooding have been developed.In the work, cross sections and the water flow have been measured. Moreover, an echo-sounding have been carried out in Funboån to map the bottom topography. From the bottom map and laser scanned data covering the study area, a terrain model was created.

Design av försöksanläggning för trycksatt rökgasrening vid oxy-fuelförbränning

Reducing the CO2-pollution, resulting from the combustion of fossil coal for energyproduction, is important to affect environmental changes. One way to achieve a reductionis to use the oxy-fuel technology. The technology uses O2 and re-circulated flue gasduring the combustion which results in a flue gas mainly consisting of CO2. The flue gascould then be compressed and stored without environmental effects. A problem thatfollows from the compression is the risk of acidification in sensitive parts of the process.Acidification can occur because of reactions following from the contact of condensedwater and sulphur- and nitrogen-oxides which are also present in the flue gas.This report compiles and evaluates the basis of a scientific unit with the purpose ofexploring the possibilities of extracting impurities of SOx and NOx from the flue gases.The dimensions of the unit are based on basic conditions, defined for an existing oxy-fuelprocess at Chalmers, and on the results of computer modelling.

Alternativ till fiskbaserat foder till karnivora fiskar

If one looks at physical planning in Sweden today one can see that while talking about densification of existing development, reduced emissions and careful use of important land, urban sprawl is a fact with development of sheer residential districts in the urban edges and shopping malls in each and every municipality. As sustainable development is an essential goal for physical planning to strive towards, it is worth questioning if the direction of today?s planning will lead to the goal. A sustainable development can be seen as an obvious to goal aim at. In reality the aim means a hard and complex work.

Hårdfräsning i verktygsstål : Förslitning av skäregg

This thesis work is made by Torbjörn Johansson on Karlstad University for Uddeholms AB. The assignment in this thesis work was to investigate tough cutting in three different tool steels: Vanadis 4 Extra, Vancron 40 and Sverker 21. The research was to compare the wear of the tool after cutting in each one of the tool steel alloys. The research was also made to see if the tool cutting in Vancron 40 has a better wear than the tool cutting in Vanadis 4 Extra and also compare the results with Sverker 21. All three of these alloys are a part of Uddeholms AB:s range of products, and is used in applications like forming tools and knife tools. Vancron 40 is a powder steel with a very good combination of mechanical properties like ductility, adhesive strength and hardness.

Smak och konsistens hos ost : en litteraturstudie kring årstiderna och fodrets inverkan

To enjoy the richness of the grazing cows and high yield during the summers, even during the winter, cheese has been the way to store milk for thousands of years. Nowadays yield is high all year around and the cheese production is possible during all seasons. The aim of this paper is to investi-gate how and why the seasons influence taste and texture of pressed and ripened cheese. Milk is composed of proteins, fat, lactose and water but contains also a lot of vitamins. The quality of milk is very important for the final constitution of cheese.

Minimera färgbortfall vid vattentvätt inom textilkonservering Med användning av cyklododekan, tvålagersmetoden eller ultrarent vatten

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2014:26.

Utsläpp av växthusgaser under islossning i små boreala sjöar

Freshwater ecosystems have long been neglected as an important part of the global carbon cycle. However, research shows that most of the world?s lakes are net-heterotrophic and consequently emitters of greenhouse gases to the atmosphere. In many boreal and north-temperate lakes, most of the yearly emissions usually occur in spring, shortly after ice-thaw. The aim of this study was to quantify the flux of carbon dioxide (CO2) and methane (CH4) in three boreal lakes, during this annual event.

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