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914 Uppsatser om Hydro plant turbine - Sida 23 av 61

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in the event of rainfall. An increased level of radioactivity in the plants may occur due to interception and retention of the radionuclides. If the content of the plants is above the threshold limit value, entire yields may have to be destroyed. In order to prevent contamination or decrease the content countermeasures can be taken. The impact of the biomass, leaf area index (LAI) and growth stage of the plant on the interception and retention is important to know in order to decide which countermeasures to use. Weather may also be an important factor. In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley and spring oil-seed rape was studied.

Ekonomi i vallfrödominerad växtföljd :

This is a project about how you grow timothy seed and red clover seed successfully. The main part is about economic analyse to see if it is any economy by growing leyseed. There are lots of things to be aware of to get all the costs in your economic analyze. Timothy Timothy seed is planted on 4400 hectares in Sweden. It is possible to grow timothy seed in the south part of Sweden. Timothy is very sensitive for dry weather in spring and in the beginning to summer. Timothy gives acceptable harvest of seed for about three years. Red clover Red clover is also sensitive for dry weather and is suitable to grow in the south part of Sweden.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in theevent of rainfall. An increased level of radioactivity in the plants may occur due tointerception and retention of the radionuclides. If the content of the plants is above thethreshold limit value, entire yields may have to be destroyed. In order to preventcontamination or decrease the content countermeasures can be taken. The impact of thebiomass, leaf area index (LAI) and growth stage of the plant on the interception andretention is important to know in order to decide which countermeasures to use.Weather may also be an important factor.In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley andspring oil-seed rape was studied.

Importance of mire plant community composition when estimating ecosystem level methane emission

Metan är en stark växthusgas som är viktig att ta med i beräkningarna när det gäller klimatförändringar. Feedback från myrmarker vid en ökad temperatur i samband med klimatförändringar har diskuterats, bland annat eftersom myrmarker är en källa för metan till atmosfären. Det finns många faktorer som påverkar metanemission, och en av dom är vegetation. Olika sorts vegetation tros bidra olika mycket till avgivningen av metan. Syftet med denna studie var att undersöka hur stor betydelse det har att ta med olika växtsamhällens sammansättning i beräkningarna för att uppnå korrekta uppskattningar av metanemission från myrmark på ekosystemnivå.

Fröskörd av hampa : metoder och tekniker för fröskörd av industrihampa

Hemp is an ancient cultivated plant that came to Sweden in the 1st to 2nd Century and was particularly interesting for use for food, clothing and building materials. Over time, other applications have been developed for hemp, e.g. in energy and health products. Interesting new uses for hemp continue to be identified and this fascinating plant has incredibly versatile applications.In this project, seed production of industrial hemp in Sweden was studied and evaluated. Five different methods are described, four of which are proven under Swedish conditions.

Jordbruksdränering, kostnader och genomförande :

Underdrainage is a costly investment but often a necessity to maintain rationalized plant cultivation, one can also see underdrainage as insurance to successful plant cultivation. Late ripening crops, low yield and difficult tillage cultivation are examples on an insufficient drainage. (Kvarnemo 1983) A drained field rise in land price and the scheme of the tiled drains is seen as a value item. The interest for underdrainage among the farmers follows with shifting economic situations within agriculture and has for long time been low. A big part of the Swedish tiled drainage systems is since 1930 and ahead. Many of these tiled drainage systems need to be replaced or complemented. The life length of one tiled drainage system varies with maintenance but can still remain in good function after 75 years with correct management.

The influence of active bomas on habitat choice of the common warthog (Phacochoerus africanus)

The common warthog (Phachocoerus africanus) is a relatively long-legged pig with noticeable curved tusks, a short neck and three pairs of facial warts. It has four recognized subspecies. The common warthog is a non-migratory ungulate living on the African savannah. It is a hindgut fermenter and predominantly dependent on high-quality foods. It prefers open areas for grazing but use bushes for cover.

CFD beräkning på en jetmotorinstallation

Hawk Turbine AB tillverkar mindre jetmotorer som ofta används i små obemannade och radiostyrda flygplan. I flygplansmodellen Lockheed T-33 Shooting Star är motorn monterad inuti planet varför luften måste ledas ut till atmosfären. För bästa möjliga prestanda måste ejektorn och utblåsröret som leder luften dimensioneras efter motor och flyghastighet.En 3-dimensionell CAD modell av flygplanets installation skapades och därefter simulerats i en virtuell vindtunnel med hjälp av datorprogrammet SolidWorks Flow Simulation. Flera olika utblåsrör i varierande storlekar samt olika former har testats för att avgöra om ändringar kan förbättra prestandan ytterligare.Simulationsresultat visar att det går att förbättra nuvarande konfiguration med 5,99 % om diametern på utblåsröret minskas från 75 mm till 70 mm med en bibehållen form på utblåsröret..

Energieffektivisering av färskvattensystemet på Skärblacka pappersbruk

The purpose of this master thesis was to study the water system for mechanically cleaned water at Skärblacka mill, in order to find and evaluate possibilities of using energy more efficiently. The thesis also includes an evaluation of the software tool ?Pumpanalys?Skärblacka mill produces pulp and paper. The large amount of water required is cleaned mechanically through filters and called mechanically cleaned water (MR0). The MR0 water is pumped out to the factory by four crude water pumps.

Urban vindkraft : Vindkraftsprojekt Järvafältet & vindkraft i Sverige

Wind power is an energy source that is becoming increasingly popular in Sweden and around the world. The establishment of large wind farms supply and contributes to energy production within grid in search of a more sustainable energy production. Wind power is becoming more popular and opens up new areas of implementation. More cities are starting to use small-scale urban wind power, everything from full-scale work for a little less work adapted to the villas. Sweden has high goals regarding the production of green electricity and the work which deals with the conditions Sweden plays in achieving those goals.

Effect of plant maturity at harvest of haylage on digestibility and faecal particle size in horses fed forage-dominated diets

Time of harvest affects nutritional value and digestibility of haylage since plants are in different developmental stages. The aim of this study was to examine the effect of plant maturity of haylage cut in June, July and August on digestibility and faecal particle size in horses.Forage and faecal samples used for the analysis of apparent dry matter digestibility (DMd) and particle size distribution in faeces were from a feed-study performed in the autumn of 2009. Twelve horses were used in the study, divided into three groups in a change-over experiment. Each group was fed haylage harvested in June, July or August during three periods. Faecal grab samples were taken from each horse and pooled so that one sample represented one horse during one period.

Planteringar på Marieholm med 1800-tals växtmaterial och tillhörande skötselplan

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Trädgårdens hantverk och design, 22,5 hp, 2014.

Nyckeltal för älg och fodertillgång på tall Pinus sylvestris och rönn Sorbus aucuparia

It has been shown that moose can affect plant community composition and structure. Selective browsing with other damages of large herbivores on tree species with different tolerance to disturbance could reshape the tree layer in both managed and natural forests. Rowan Sorbus aucuparia is widely distributed throughout Sweden and Europe. Research has shown that browsing by moose may prevent rowan from reaching browsing safe heights. The goal has been formulated that, where rowan is indigenous, it should have a good competition status and be able to reach tree level.

Patotyptest av potatiscystnematoden :

There are two species of potato cyst nematode (PCN), the yellow, Globodera rostochiensis, and the white, Globodera pallida. Each of them can appear in different pathotypes. These are separated by testing the nematode ability to multiply on a number of potato cultivars with different resistance properties. The aim of this project was to examine the virulence of Swedish and foreign PCN populations and to compare two test methods. Biotests are today the only available tests used to study virulence.

Sammankoppling av fjärrvärmenäten i Nyköping och Oxelösund : miljö- och systemkonsekvenser

District heating covers most of the residential areas and industries in the twoneighbouring Swedish municipalities Nyköping and Oxelösund. In Nyköping,Vattenfall AB Värme produces heat in a bio-fuelled CHP plant. In Oxelösund,waste heat and use of waste gases from the steel production at SSABOxelösund is the basis in the district heating system.This report examines the environmental consequences of a connection betweenthe two district heating systems. A broad system approach is used and the focusis on environmental effects in the system.A system analysis has been performed on the result of simulations of differentheat and electricity production alternatives. The alternatives simulated wereone where Vattenfall Nyköping covers the base load in the joint district heatingsystem and two where the power plant at SSAB Oxelösund supplies the heatbase load.The conclusion in this report is that the consequences of connecting the twodistrict heating systems can be both positive and negative, depending onsystem boundaries and on the environmental focus.

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