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1616 Uppsatser om Surface water - Sida 42 av 108

Optimering av glödgningsparametrar för kromstål

At Sandvik Materials Technology, Argon gas is used as furnace atmosphere when heattreating hot rolled wire. Upon heating chromium steel wire, a rich oxidelayer forms on the wire surface. The abstract of this masters thesis is to enhance the understanding of the constitution of the oxidelayers and the influence of the furnace atmosphere. This will be achieved by performing a number of annealing experiments on laboratory level. Also, the aim is to understand the chemical reactions and physical mecanisms controlling the pickling process.

Nitrat i dricksvatten : jämförelse av nitrathalter, mellan åren 1975 och 2005

Ronneby Miljö- och hälsoskyddskontor ville genom undersökningen få information om nitrathalter ienskilda dricksvattenbrunnar inom kommunen, med bakgrund av den nya miljökvalitetsnormen.Riktvärdet för nitrat är 50 mg/l. Halter som överstiger detta bör inte ges till barn under ett års ålder pågrund av risk för methemoglobinemi. Jämförelsen skulle ske mellan områden präglade av jordbrukrespektive skogsbruk, samt mellan grävda och borrade brunnar. Jämförelsen skulle även ske över tiden,mellan 1975-1990 till 2005. Urvalet av provtagningspunkter baserades på en sammanställning frånbefintligt arkiv samt efter en annons i dagspressen.

Våtmarker i urbana miljöer : växtgestaltning och planering

The practice of landscape architectural involves forming the space in our cities and suburbs, as well as the landscape surrounding. The need of exploiting green environment leads up to, among other issues, flood problem during heavy rain and overfed water environments. The problem is partially caused by the shortage of knowledge, how the environment is responding of the innovations made by the city- urban planning and how to get sustainability. Research and knowledge how to take care of our environment, in a natural way, is increasing. The object of the thesis is to propose control and balance in urban wetlands, and discuss the difference a plant design can do. The thesis deals with discourses in the field of landscape architecture, biological diversity, dam construction, limnology, planting design and management, pollution of the environment and urban design practice.

GRÖNYTEFAKTOR I ETT NYTT PERSPEKTIV - Går ekosystemtjänster att mäta med fjärranalys?

Due to an increased population in cities the need of densification of cities increases. This means that the amount of ecological elements in the city is at risk of decreasing. Ecological services contribute to the city?s climate by softening the negative impacts that densification of cities means. Thus increases the will and ambition in city planning in to preserve greenery.This is an interdisciplinary thesis within the subject of geography that studies Biotope Area Factor (BAF), a planning tool that is used in city planning with the purpose of compensating for lost ecological services associated with new housing estate.

Våtmarker för näringsretention i Lillån : var bör de ligga och vilken effekt kan vi förvänta

Construction of wetlands in the agricultural landscape may reduce nitrogen and phosphorus transfer to streams, thereby reducing the eutrophication of lakes and seas. The agriculturalstream Lillån, a tributary to stream Sagån, ends up in Lake Mälaren and is transporting large amounts of these plant nutrients. The aim of this study was to estimate how hypothetical wetlands of different size and location may reduce nitrogen and phosphorus load from stream Lillån. Estimated nutrient retention in several small wetlands was compared to retention in a single large wetland based on existing data from the agricultural stream and from a nearby smaller stream. Retention in the stream was suggested to decrease along with the nutrient concentration in the water.

Klimatsäkrare städer : klimatförändringar, stadsplanering och översvämningar

The numbers of natural disasters caused by extreme weather are increasing through out the world. A large majority of the research concerning the climate shows that this is a trend that can be expected to continue. At the same time the urbanisation is increasing more than ever and for the first time in history more than fifty percent of the population lives in a city. How we build these cities will have a crucial importance for our adaption to the new climate. In Sweden, our capacity for an adaption are high because of our economic situation as well as our rather well built society.

Näringsretention i återskapad våtmark på betesmark : studier av en mad vid Bornsjön

It is important to construct or recreate different types of wetlands and study their retention of nutrients, since knowledge of their effectiveness in this matter is poor. In 2003 a wetland was constructed on an old meadow on the western shore of Lake Bornsjön in central Sweden. The main purpose of the wetland was to reduce the amount of phosphorus entering the lake, which is the back-up water supply for Stockholm when the city cannot obtain water from Lake Mälaren. Large areas around Lake Bornsjön consist of agricultural land and the nutrient concentrations in the inflows to the lake are usually relatively high (approx. 1 mg/l total nitrogen and 0.05-0.1 mg/l total phosphorus).

Framtidens Hus

The company Sol & Energiteknik wanted to examine the possibility to make a standardhouse totally energy independent. Based upon this I have, during the spring of 2007,examined the possibilities available at the market today through litterature studies, contactwith several companies and reading reports at the internet.The first thing to examine has been to determine the energy consumption for a standardhouse, and find out if there are better technologies to be used for energy conservation.My conclusion in this matter is that there are possibilities today for building a house moreenergy efficient.When I had reached the point at which my design for the house was decided, I also hadto choose the different products to use to produce energy as well as to store that energy.To produce heat and electricity to the house I decided to use a wind turbine and a solarwater heater.The most difficult part of designing a house that is energy independent is that theproduced energy must be stored somehow. Storing the heat is relatively easy beacuse theheat can be stored in a large water tank. The electricity is a bigger problem beacuse itmust be stored in batteries, which today are too expensive to be used in a standard house.In the future producing and storing hydrogen might be used to produce electricity, buttoday that technology is both expensive and not tested enough.My final conclusion is that a standard house can not be built to be totally energyindependent today, unless it is very expensive to connect the house to the electricitynetwork. As an alternative solution I came up with a proposal for a house which isconnected to the electricity network and have some amount of own produced energy.This house prooved to be a good investment if you choose to build it today, and it couldbe a very good investment in the long run beacuse energy prices increase every year..

Torkning av vallfrö :

In Sweden, grass is the single largest crop grown. Nearly 1 000 000 Ha grows on the fields, this is primarily used as feed for livestock. To get a good seed, you need to handle the crop carefully from planting to delivery. The part that I have been interested in, is how to dry the harvested seed with out destroying the growth in the small seed. This is very easily done if you aren?t careful during the drying period.

Trafikklasser för markplattor av natursten : förslag till klassificeringstabell

This report deals with hard surfaces and the factors which are behind the criteria for dimensioning, also dependent on the level, or volume, of traffic. A test was made on slabs of two kinds of natural stone. This was made to see if the values that were reached for breakload was transferable to the same tables that the concrete industry is using for surface dimensions of slabs and paving stones. The test showed very high values and the result, together with the written study, led to the author?s suggestion for a classification table where slabs of natural stone were divided in to different classes depending on traffic, thickness and durability..

Allt är möjligt hus i Gustavsberg

In a sequence described in the next paragraphs, I remove the poorly insulated roof of Gustavsberg Porcelain Factory and make new use of its  foundation. The monolith cement slab, once supporting heavy industrial machinery, is now the site of lakes and other movements:The top floor area is split, and a new built volume, one story higher, overtakes the southern half resting on the factory?s basement, digging into it at its western and eastern ends. Striking horizontally, the fissure exposes a long central axis, taking advantage of the factory?s horizontality to articulate vastness .

Utsidan räknas : ?En materialstudie

Judged by appearance. This is the conclusion of research made on shopper behavior that revealed that consumers tend to go by their instinct when evaluating vacuum cleaners in a purchasing situation. Many buy the first vacuum cleaner they interact with and few buy pre-planned brands. Almost none even turn the machine on before taking a purchase decision.Electrolux Floor Care Europe has their factory for vacuum cleaners in Hungary. Increased competition from China makes it harder to "only" produce vacuum cleaners with good performance.

Snabbare, högre ...och det Tredje Könet : Om könsgränserna inom idrotten och överträdandet av dessa

This thesis examines the gender boundaries in sports. I do this by exploring three cases in which these boundaries, at least on the surface, have been questioned: the transsexual tennis player Renée Richards, the east European runners Marita Koch and Jarmila Kratochvilova and the Swedish golf player Annika Sörenstam. The results point out different mechanisms that contain the"danger"and restore"security". But they also point out a criticism against the struggle for equality in sports, which is based on the preserving of differences and therefore cannot challenge the ideological assumptions about gender in sports..

Trycksatta huvudvattenledningar : Guide för material och schaktfria metodval vid åtgärder av vattenledningar

Detta examensarbete har utförts på uppdrag av Johan Lundberg AB som har haft ett behov av att det tas fram en guide vid åtgärder av vattenledningar. Åtgärder kan innebära nyläggning, utbyte eller renovering av en vattenledning. Syftet med rapporten är att ta reda på om ett visst material eller metod kan användas till vattenledningar, få fram för- och nackdelar med dessa material och metoder, både för installationsfasen och för driftsfasen. Detta görs ur ett långsiktigt tekniskt, ekonomiskt och miljömässigt perspektiv. Rapporten innehåller en faktadel med tänkbara material och schaktfria metoder och sju stycken intervjuer med ledningsägare har genomförts och en sammanställning av dessa intervjuer presenteras i kapitel 5.3.

En internationell jämförelse av miljölagstiftning avseende växtnäringsläckage med ursprung i jordbruket

SAMMANFATTNINGÖvergödning har de senaste åren blivit en stor och omdebatterad fråga i många EU- länder.Även om problemen har minskat en del är detta inte tillräckligt, vi ser fortfarande fiskdöd,syrefria bottnar och giftiga algblomningar. Hur långt ska vi gå för att kunna övervinnaövergödningsproblemen? Genom olika sorters lagstiftning, ekonomiska styrmedel ochrådgivning har vi nått en bit på vägen, men fortfarande krävs det mycket arbete innan vi haruppnått målet. Jordbruket har pekats ut som en av de största källorna till övergödning pågrund av överskottet av kväve och fosfor som varje år urlakas ur våra jordbruksmarker.Inom EU finns sedan 1991 en gemensam lagstiftning; Nitratdirektivet. Syftet med direktivetär att minska nitratföroreningar och andra föroreningar från jordbruket, då dessa påverkarsåväl yt- och grundvatten som kust- och havsvatten.

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