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710 Uppsatser om Carbon and peat filter - Sida 8 av 48
Hur skall skogen skötas? ? en analys av skogsfastigheten Fagerdal 2:10 i Jämtland
The forest property Fagerdal 2:10 was donated to the Swedish University of Agriculture in 1995 by Erik Rönnberg. The dominating species is Norwegian spruce (Picea Abies) and the average age is high due to selective cutting. The aim of this study has been to analyze how the forest on the property should be managed and demonstrate how a better estimated forest data affects the future management. The impact of the management on the carbon stock of the property was also examined.
A forestry plan established in 2009 by Skogssällskapet was used as a basis for the analyses.
Annonsmediers miljöpåverkan : när ska miljön få en reklampaus?
The aim of the thesis was to investigate energy consumption and carbon dioxide emissions from an advertisement broadcasted on the radio or the television or
distributed through press. The object was to calculate the amount of carbon dioxide emissions per individual receiver of an advertisement in Sweden. There was no room
for a deeper investigation into editorial work within the framework of the thesis.
Consequently, main focus of the radio and television study was on broadcasting itself and the components involved. Focus for the press study was on paper production,
printing and distribution. Production and discarding of media equipment was not taken into account.
Mesatorrhalt
AbstractDegree thesis Solid content in Lime Mud By Andre Flodin Process operator program ? Umeå University 17/6 ? 2014 Pages: 21A thesis was made on Billerudkorsnäs production unit in Karlsborg where lime kiln in the causticising department of chemical recovery plant does not meet the required production. Causticising department is the final step in the chemical recycling unit. There, the filtered green liquor is mixed with lime to recover the cooking chemicals used in the pulp factory. The cooking liquid is called white liquor.
Implementering av digitalt vågfilter av Richardstyp i FPGA
Ett digitalt vågfilter av Richardstyp har implementerats i en FPGA på ett utvecklingskort. Sampel kan skickas till filtret och mottas från filtret via serieporten på en dator. Metoden som användes är att en modell av filtret konstruerades i Simulink. Filtret har modifierats med avseende på skalning, brus och stabilitet. VHDL-koden till filtret genererades i Simulink genom att bygga modellen av Xilinx Blockset.
Carbon sequestration in the pastoral area of Chepareria, western Kenya : a comparison between open-grazing, fenced pastures and maize cultivations
Carbon sequestration through restoration of degraded pastoral soils is an advocated way of mitigating global warming, and simultaneously alleviating poverty. An often proposed rehabilitation strategy is fencing of pastures, a method that was introduced to the farmers of Chepareria by the Vi-Agroforestry organization in 1987. The landscape of Chepareria changed from eroded, over-grazed grasslands, to a mixture of open-grazed commons, pastoral enclosures and cultivations. The aim of this study was to investigate (1) if the soil organic carbon (SOC) is higher inside the enclosures than on the open-grazed commons, (2) if SOC is affected by duration of fencing and (3) what effect cultivation of pastures has on the SOC. Estimations of vegetation cover and deep profile (100cm) soil sampling was performed on six clusters containing; (1) open-grazing (OG) (2) 1-5 years of fencing (FENCED(1)), (3) 7-10 years of fencing (FENCED(2)), (4) 15-23 years of fencing (FENCED(3)), (5) maize from OG (A(OG)), (6) maize from fenced pasture (A(FENCED)).
Avskiljning av uran från dricksvatten med reaktiva filter :
Water is our most important provision and its quality is above all dependent on the
geological conditions in the area from where it is extracted. Due to geological
properties there are certain areas with an elevated risk of high uranium levels in the
ground water, which in turn constitutes a risk for human health. Consumption of water
that contains a high concentration of uranium implies a health risk due to the chemical
characteristics of uranium. Livsmedelsverket (The National Food Administration) and
Socialstyrelsen (The National Board of Health and Welfare) therefore recommend that
precautionary measures should be taken when the uranium concentration in ground
water exceeds 15 micrograms per litre. In particular, drinking water collected from
wells in areas with uranium-rich bedrock may have a harmfully high level of uranium.
One of the wells of the Ärla water purification plant, located near Eskilstuna, Sweden,
contains water that exceeds the guideline of 15 micrograms per litre.
One interesting technique for removing uranium from drinking water is adsorption to
reactive filter materials.
Klimatpåverkan vid vägbyggnad -beroende av vald konstruktion
It?s a fact that the climate is affected by the vehicle that runs on the worlds roads. But theconstruction of the road itself is rarely thought of as a climate threat. Svevia and the Swedish roadadministration have opposite views of how the construction of roads should be carried thru. It?sthe difference between those two construction methods that is the base in our thesis.The amount of energy use or the emissions are not analyzed for neither the Swedish roadadministrations nor Svevias construction models.
Inflationsprognoser i Sverige: Vilket gapmått bör användas?
Syftet med denna uppsats är att undersöka huruvida BNP-gap kan förutspåinflationen bättre jämfört med arbetslöshetsgap. Svensk kvartalsdata från1993 till och med 2005 har använts. Gapmåtten skapas med två olika metoder,en linjärregression och ett HP-filter. En direkt prognosmodell används föralla prognoser med out of sample metodik. Prognoshorisonterna somanvänds är ett kvartal, fyra kvartal samt åtta kvartal.
Effekten av kvävegödsling på gasproduktionen vintertid i boreala sjöar
To investigate effects of nitrogen on in-lake CO2 and CH4 production during winter, three pair of lakes was subject for a fertilizing experiment in which one lake in each pair was fertilized with nitric acid (HNO3) directly into the water column in the summer of 2012. The lakes in each pair are assumed to be morphologically, hydrologically and biologically similar, that is, the non-fertilized lakes are considered references. The pairs do differ in one major way by being progressively less humic, going from around 25 mg/l to 10 mg/l DOC. Sampling and analysis was carried out at the end of the frozen period in 2013. Results show a significantly higher concentration of both CO2 (p<0,001) and CH4 (?=0,1, p=0,053) between impact and reference sites in the two less humic pairs.
Gestaltningsförslag till ny förskola på Zakrisdal
Due to increasing regulations regarding new diesel vehicles particulate matteremissions the new Scania truck, Scania Euro 6, has been equipped with a particulatefilter. This component effectively stores the particles in the exhaust gas but must becleaned in order to prevent itself from clogging. The filter is cleaned through aprocess named regeneration which is a thermodynamic process in which thetemperature of the filter is raised through fuel supplied to the exhaust gas.The purpose of this thesis is to contribute to the development of improved controlstrategies of the temperature during the regeneration process through thedevelopment of model-based controllers. These controllers are designed in order tohave good performance in stationary as well as automatic regeneration.In order to develop these model-based controllers a model of the system isconstructed. The model is described as a linear thermodynamic grey-box model withflow varying parameters, showing good results in validation.The model provides a simulation environment during the controller design, which isfocused around the development of linear regulators with the exhaust gas mass flowas a scheduling variable whose size determines controllers? mode of operation.
Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon
Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques.
The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.
BIODIVERSITETS P?VERKAN P? M?NGDEN ORGANISKT MATERIAL I ALSUMPSKOG: En fallstudie i fyra alsumpskogar p? svenska v?stkusten
Globally, coastal ecosystems like mangrove forests, sea grass meadows and salt marshes are well known for their ability to capture and store atmospheric carbon effectively. In Sweden, there is still limited knowledge about local coastal ecosystems with similar functions, with alder swamp forests being an interesting example. Therefore, this study aimed to increase knowledge of the factors that can contribute to the potential carbon sequestering ability of alder swamps. Vegetation data and sediment samples were collected from a total of 37 sampling plots across four alder swamps in Bohusl?n on the Swedish west coast.
En indirekt metod för adaptiv reglering av en helikopter
When a helicopter is flying, the dynamics vary depending on, for example, speed and position. Hence, a time-invariant linear model cannot describe its properties under all flight conditions. It is therefore desirable to update the linear helicopter model continuously during the flight. In this thesis, two different recursive estimation methods are presented, LMS (Least Mean Square) and adaptation with a Kalman filter. The main purpose of the system estimation is to get a model which can be used for feedback control.
Impact of Eucalyptus plantations on pasture land on soil properties and carbon sequestration in Brazil
Soil organic carbon (SOC) stocks and fluxes in forest ecosystems are influenced by natural and human disturbances. In the tropical regions the highest impacts on disturbance in forest C cycles are related to human activities such as conversion of natural lands to cropland and pasture areas and to forest plantations. The disturbances in the forest C cycles will release CO2 emissions to the atmosphere triggering global warming. In this study the focus was set in subtropical soils in Brazil, south extreme region of Bahia. The aim of the study was to investigate whether reforestation of Eucalyptus plantations under former pasture areas will help mitigate climate change through carbon sequestration.
Miljödeklarering av konsumentprodukter : En undersökning om svårigheterna med att implementera ?Carbon Footprint?
För att kunna gå en hållbar morgondag tillmötes är det viktigt att miljöpåverkan från oss människor uppdagas och sätts i balans. Växthuseffekten är en av de världsomfattande angelägenheter som visat sig påverka ekologin och som för med sig stundande klimatförändringar vars utbredning ännu inte går att förutspå. Förändringar i våra rutiner måste till, och en del i det hela är att öka medvetenheten för utsläppen som sker inom industrin. Kännedomen om storleken och härkomsten av utsläppen är viktig såväl till insikt för konsumenterna som till underlag för vart företagen ska fokusera sitt miljöarbete.Genom att tillämpa livscykelbaserade analysmetoder får företagen en utförlig bild över omfattningen av miljöpåverkan som sker associerat med en produkt. Ett sådant arbete kan även komma att mynna ut i en miljövarudeklaration som kan användas av företaget i syfte att kommunicera utåt mot konsumenter och affärspartners.