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964 Uppsatser om Surface temperature - Sida 62 av 65

Löslighet och metylering av kvicksilver i en förorenad sjö (Ala-Lombolo) i Kiruna kommun :

Transformation of inorganic mercury (Hg) to methyl mercury (MeHg) is a biotic process that is proposed to be conducted primarily by sulphate reducing bacteria (SRB). The formation of MeHg is of great interest because it is the mercury species that biomagnifies to the greatest extent in the aquatic food webs; about 90 % of all Hg in fish is MeHg. Our understanding of factors involved in the production of MeHg is very important for making a reliable risk assessment. The purposes of this study were to investigate the different factors that control the solubility of Hg and the production of MeHg in a contaminated lake sediment. The lake Ala-Lombolo, Kiruna municipality, is well-known to be contaminated by mercury from different sources. Sediment cores were sampled at three different locations (N, SW and SE) in the lake and divided in three different layers; 0-5, 5-10 and 10-15 cm.

Development of new food products with components active against Helicobacter pylori - with purpose to improve gastric health in humans

Gastric and intestinal disorders are common and costly human health problems worldwide. Helicobacter pylori are a gram-negative, pathogen bacteria and the most common cause of duodenal and gastric ulcer in the stomach the intestinal mucosa. Prolonged infection and colonization can lead to chronic gastritis and stomach cancer. H. pylori are present in the gastric and intestinal mucosa of half of the world population and a relation between infection and low socioeconomic status has been shown.

Chemical and sensory analyses of juice, cider and vinegar produced from different apple cultivars

The interest for locally produced food is increasing due to consumer concern about the environment, distrust of industrial foods and a demand for high quality products. Apple is the predominant fruit crop in Sweden, and by processing apples into cider and vinegar, these products could significantly contribute to the development of the market of local foods.In this study different yeast types and different bacterial cultures were evaluated for their suitability in cider and vinegar production from cloudy apple juice. Ten apple cultivars (Aroma, Baldwin, Belle de Boskoop, Bramley, Cortland, Gravensteiner, Ingrid-Marie, Jonathan, Rubinola and Spartan) were also evaluated for their suitability for production of juice, cider and vinegar. Chemical analyses including total soluble solids, titratable acidity and total phenols were performed on the products along with sensorial evaluation by taste panels.The yeast strains were shown to have an effect on fermentation rate and the resulting content of total phenols in ciders fermented from cloudy apple juice. Dry commercial starter strains gave a higher appreciated cider compared to cider that was spontaneously fermented, and the ale yeast Safale S-04 was concluded to be the most suited for fermentation of cloudy apple juice.For vinegar production, the bacterial culture had an effect on TSS, but not on any other chemical or taste characteristics.

Bergerosion i utskovskanaler

Today?s climate changes will probably give rise to precipitation in Sweden, which will cause more floods in Swedish rivers. Many of the Swedish rivers are regulated and have lots of hydro-electro power plants. Higher floods in the rivers will give greater water loads on the dams, which mean that a higher discharge through the sluice gates and in the spillway channels is needed. High discharge of water in a spillway channel can create scour of the material in the channel.

Vermicompost for reduction of vegetable waste - and a possible means to produce fish feed in aquaponic systems?

Aquaponics is a food production system consisting of a consecutive cultivation of plants and aquatic animals, fish or shellfish, in recirculating water. The plants feed on the nutritious effluents from the fish tank and bacteria converts ammonia from the fish tank into nitrate that is absorbed by the plants. The plants receive nutrition and the fish gain purified water. The environmental impact of the production of fish meal and fish oil used in conventional fish feed includes a large consumption of fossil fuels with subsequent carbon dioxide emission. The aquaponic system can be made environmentally sustainable and self-supporting if supplemented with a vermicompost/vermiculture for the production of worm protein as a fish feed. Vegetable waste from the hydroponic part of the system can be reused as worm feed in the compost and the protein rich worms can be harvested, dried and grinded and brought back to the aquaculture as fish feed. As a first step in this direction, I have investigated the effect of recycling of vegetable waste in vermicomposts on the growth and number of earthworms (this was evaluated after harvesting). The hypotheses were that earthworms can be cultivated in the vegetable waste and that by adding manure to the vermicompost it is possible to obtain a nutrient content adequate to support a continuous worm harvest, in other words create a vermiculture. Eisenia fetida and Dendrobaena veneta were grown in 20 L bins containing peat mixed with either poultry or cattle manure. The proportions were 70% peat and 30 % manure. Discarded plant parts from lettuce cultivation was added to the vermicomposts (35 g per week) and water was supplied with 0.8 L per week.

Land Art och landskap : en studie av tre Land Art-projekt ochderas förhållande till landskapet

My purpose with this thesis has been tostudy the intersection between Landscapearchitecture and Land Art. They both relateto the landscape in some way whetherit is to the urban landscape or thenatural landscape.What tangent points are there betweenthese two subjects, and can you learnsomething of the artists approach to thelandscape?Land Art is an art movement that began inthe late 60?s, what links are there to thecurrent landscape?Last summer, I travelled around the U.S.for a month and visited the three classicLand Art projects. Lightning Field in NewMexico, by Walter De Maria, Sun Tunnels inUtah, by Nancy Holt and the Spiral Jetty,also in Utah, by Robert Smithson.The sites where visited from half a day upto 24 hours and was described and analyzedwith text and photographs.To visit these sites has been crucial formy thesis and will affect my future workas a landscape architect. The use of themethod has been a thought of mine for along time, particularly to analyze ordescribe a landscape with images.

Handel med utsläppsrätter - hur företagsstrategier påverkas :

Climate change is one of the most difficult problems that humans have to deal with. Today, the evidence of human effects on the climate change and the rise of temperature on earth are strong. It is extremely important that all countries get together and cooperate in order to be able to solve the problem with climate change. One step in the work on climate changes is the Convention on Climate Change, which was agreed on in 1992. The Convention on Climate Change resulted in the Kyoto Protocol in 1997. The Kyoto Protocol is an agreement between a number of industrialized countries to limit or reduce the green gas emissions.

Tillväxt hos Husmossa (Hylocomium splendens) i boreal skog och växthus : effekter av ökad vattentillgång

Hylocomium splendens (Glittering wood-moss) is a common species in the Nordic countries and can be found in many different types of boreal forests. It usually forms dense moss carpets on the forest floor. The shoots grow in segments and new segments form annually on the previous years growth. The size of the segments is probably regulated in a high extent by local micro environmental conditions. Previous experiments suggest increased growth of H.

Metodik för beräkning av anslutna hårdgjorda ytor till spillvattennätet

Sveriges avloppsledningsnät förnyas och utvidgas kontinuerligt. Idag finns ett flertal datorprogram för hydraulisk modellering av flöden och uppdämningsnivåer i spill- och dagvattennät. Modellerna kan även användas som planeringsverktyg för att bedöma effekter av planerade åtgärder samt för uppföljning av utförda åtgärder. Vid uppbyggnaden av en modell krävs beräkningsresultat från en hydrologisk avrinningsmodell som indata. Det största arbetet vid modelluppbyggandet ligger just i beskrivningen av hydrologin.

  Genomgång av Turbomin 100 :   Förstudie och föreslagna förbättringar av undervisningsjetmotor Turbomin 100

ABSTRACTThis project thesis has been written at the request of Mälardalens University, Västerås.The aeronautical engineering students at Mälardalens University and the pupils of Hässlö upper secondary school, all gets the opportunity to perform a computation lab with a real turbojet engine during their study. The goal of the lab from the University is that it should give the students applied experience from the theory part of which has been tought in the course ?Aircraft Engine Technology?.                      The pupils of the Hässlö upper secondary school are performing simpler calculations from the measured values of the equipment. This turbojet engine is located at Hässlö airport in the premises of Hässlö upper seconday school.Since the installation 1989, the engine has lost both thrust and reliability. This makes the theoretical computations made by the students inaccurate.

Skillnader i vatten- och avloppshantering inom EU : En jämförelse mellan Slovakien och Sverige

The management of water resources and waste water varies between the countries of the EU. For many years, a large part of the water in Europe has been contaminated by, among other things, insufficiently treated waste water and emissions from agriculture. The EU Water Framework Directive 2000/60/EC and the Urban Waste Water Directive 91/271/EEC are intended to harmonize fresh-water management and waste water management within the whole EU, aiming at safeguarding drinking water of good quality and a high quality of all water within the EU today and in the future. There are however some problems concerning the waste-water directive. One problem is the huge investment needed in Slovakia to fulfil the demands of the waste-water directive for waste-water management in larger communities (with more than 2000 inhabitants).

Påverkar tidigare arbetslivserfarenhet lärande? : En kvalitativ studie om universitetsstudenters olika sätt att lära i relation till tidigare arbetslivserfarenhet.

Många av dagens ungdomar har svårt att komma in på arbetsmarknaden som en följd av att de saknar tidigare arbetslivserfarenhet eller eftergymnasial utbildning. Detta kan vara en förklaring till att allt fler väljer att studera vidare på universitet eller högskola. På programmet med inriktning mot personal- och arbetslivsfrågor vid Uppsala universitet har man låtit avsätta 30 procent av platserna för sökande med minst fyra års tidigare arbetslivserfarenhet. Detta innebär att en del av studenterna på programmet har arbetat i minst fyra år före studierna, medan andra påbörjat studierna direkt efter, eller i nära anslutning till gymnasiestudierna.Det huvudsakliga syftet med denna föreliggande studie var att undersöka vilken betydelse arbetslivserfarenhet har för universitetsstudenters lärande. Vidare avsåg den studera eventuella samband mellan studenternas arbetslivserfarenhet och deras syn på sitt eget lärande, samt mellan deras arbetslivserfarenhet och val av inlärningsstrategi, det vill säga ett yt- eller djupinriktat lärande.

Böklåda med torv på rastgårdsytan i ekologisk slaktsvinsproduktion : effekter på beteende och emission av kväve (NH3 och N2O)

In organic animal production, synthetic amino acids are not allowed. Therefore, a higher level of crude protein is needed in the diet to pigs, which lead to more nitrogen (N) excreted in the faeces and urine. N can be emitted to the air in the form of e.g. ammonia (NH3), which contributes to eutrophication and acidification and as nitrous oxide (N2O), which is a very potent greenhouse gas. The emission of N can be reduced by e.g.

Variation i temperaturrespons (Q10) vid nedbrytning av biopolymerer

Nedbrytningshastigheten för organiskt material i marken kan komma att förändras vid varmare klimat. I dagsläget råder dock oenighet om hur nedbrytningen av organiskt material kommer att reagera på förändrade temperaturer; forskningsrapporter pekar åt olika håll. För att kunna förutsäga framtida scenarier är det viktigt att vi får kunskap om hur organiskt material kan komma att påverkas. Om koncentrationen av koldioxid i atmosfären ökar och den globala medeltemperaturen stiger kan nedbrytningshastigheten för organiskt material öka. Detta kan leda till en positiv feedback loop där mer koldioxid avgår från marken till atmosfären.

Självkompakterande betong : Ytjämnhet utan efterbehandling

Betonggjutning är ett tungt moment inom byggproduktion och entreprenörer har länge använt betong med flyttillsats för att få en mer lättarbetad betong. Ändå har det krävts långa arbetspass och många tungarbetade moment. Efter lasernivellering, vibrering, slodning och glättning har man kunnat uppnå en yta som nästan är helt jämn. Dock ej så jämn att avjämningsmassa kunnat elimineras för att inte få sviktande parkett eller buktande plastmattor.Självkompakterande betong (SKB), eller vibreringsfri betong som man först kallade den, forskades fram på 80-talet i Japan och dök upp i Sverige i slutet på 90-talet. Det är en betong som innehåller en flyttillsats och en så kallad filler vars gemensamma egenskaper ger en betong som har bibehållen homogenitet samtidigt som den fyller ut formen och omsluter armering endast genom gravitationskraften.

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