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1194 Uppsatser om Nitrogen flow - Sida 12 av 80
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.
Läsa och samtala : Vad betyder folkbibliotekets bokcirkel för användaren?
The aim of this Master?s thesis is to investigate the meaning the reading group of the public library has to a number of users. To fulfill the aim the following three questions have been formulated: 1) What do a number of users expect from the reading group of the public library? 2) Which approach/attitude or approaches/attitudes do a number of users have to reading and to talking about reading? 3) How do a number of users experience the ongoing reading group?The research is founded on qualitative interviews with five users that take part in three different reading groups in public libraries. The theories that are used is the theory of three so called strategies - the pragmatic, the traditionalistic, the emancipatory ? and the theory of flow.
Självkörande fordon : En analys av energianvändning och kapacitet
Self-driving cars are soon to become a reality to the commercial market. A self-driving car does not have a human operator, which enables some interesting characteristics. The main benefits are considered to be:The number of accidents and traffic jams should be reduced.Enhanced comfort.Energy usage could be decreased while capacity could be increased.This study concerns the causes for improved energy efficiency. The reason for improved energy efficiency is mainly because of the variation in terms of acceleration, braking and distance holding are reduced. The vehicles are more intelligent and can work together as a unity.
Årlig gödsling med NPK bäst för gröda, miljö och ekonomi
Yesterdays common fertilizing strategy was to apply phosphor (P) and potassium (K) in thefall a few times in the crop rotation. In the spring only nitrogen (N) was applied. Recent trialsand studies has shown that this strategy, N+P/PK, is ineffective compared with the systemwhere NPK is spread every year in the spring. The strategy with annual NPK-fertilizer in thespring has proven to be better for the crop, the environment and the farmers economy.In the NPK-system the crop responds with higher yields and better quality, especially in thespring cereals. This is mainly because of an interaction between the different nutrients in thefertilizer.
Simulering av översvämningar i Byälven
Severe floods caused by heavy autumn rains in year 2000 raised the question whether measures to reduce the damage from high water levels, in the area surrounding lake Glafsfjorden and along the river Byälven down to lake Vänern, are possible. One option is to reduce flow resistance along the river and thereby lower the maximum water level a given inflow would cause. Good knowledge of hydraulic and hydrological conditions is necessary in order to estimate the effect of such flow-reducing measures. In order to quantify such effect a 1-dimensional hydraulic flow model has been set up for the river Byälven using the software package MIKE 11. The model is more detailed, especially concerning topography and bathymetry, than earlier models used for studies of the river.
Karakterisering och klassificering av gotländska ytvatten enligt ramdirektivet för vatten
In this study the practical work with the EU Water Framework starts on the island of Gotland. 33 lakes and 32 streams have been characterized and classified regarding to their ecological status. The aim with the characterisation is to create a uniform discription of all waterbodies and a comparable estimation for the future. The aim with the classification is both to study the waterbodies ecological status and to gain knowledge of where the resources should be concentrated so that the ecological status in all waterbodies will be good in 2015.The characterisation has been done according to the EU Water Framework Directive, and the factors that have been applied are the mean depth and area of the lake. The length and size on the catchment area are the factors that have been used on streams.
The effect of arginine on root system development in Norway spruce (Picea abies L. Karst) somatic embryos
The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.
Modellstudie av föroreningsretention i Bäckaslövs våtmark : Tillämpning av modellverktygen MIKE SHE WET och MIKE 21
During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland.
Konsekvenser av ny teknik på en sjukhusmottagning
An often encountered problem when implementing a mass flow regulator in a rolling mill is the one with measurement of speed. The most widely used solution is to fit a pulse counter to a wheel that is in contact with the strip. Common problems with this design are for instance scratch marks on the strip and problems with the flatness measuring system. One way of circumventing the aforementioned problems would be a non-contact measuring system. The market of today only offers systems based on the Doppler principle.This report evaluates three different systems for non-contact speed measurement. Important areas in the evaluation have been the ability to operate under normal rolling conditions, integration in existing control system and how well the sensor can be fitted to the rolling mill.
Val av teknik för hastighetsmätning i kallvalsverk
An often encountered problem when implementing a mass flow regulator in a rolling mill is the one with measurement of speed. The most widely used solution is to fit a pulse counter to a wheel that is in contact with the strip. Common problems with this design are for instance scratch marks on the strip and problems with the flatness measuring system. One way of circumventing the aforementioned problems would be a non-contact measuring system. The market of today only offers systems based on the Doppler principle.This report evaluates three different systems for non-contact speed measurement. Important areas in the evaluation have been the ability to operate under normal rolling conditions, integration in existing control system and how well the sensor can be fitted to the rolling mill.
Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff
In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.
Noble Operations: En studie av Stadshuskällarens processflöden
The aim of this thesis is to study Stadshuskällaren?s operational processe flow and identify their operational characteristics. The uniqueness of Stadshuskällaren is that they are breaking the law of trade-offs regarding volume/variety, much like Toyota managed to do ? which spawned the entire field of research of the ?Lean Philosophy?. In the thesis the characteristics we identify through analysis, which enables Stadshuskällaren to break the trade-off, are compared with the principles of Lean service theory, which ultimately stem from Toyota.
Grammatiken bakom den politiska retoriken : En syntaxstudie av före detta statssekreterare Lars Danielssons uttalanden angående sitt ansvar i regeringens hantering av tsunamikatastrofen 2004
In this thesis I based on Fowler?s method of syntax analysis construct a flow scheme which I then use to make a syntax analysis of former State Secretary Lars Danielsson?s statements, in his autobiography, regarding his responsibility in the Swedish government?s management of the 2004 Indian Ocean tsunami disaster. The focus of the flow scheme is how grammatical constructions can be used in the interest of rhetoric?s to on the syntax (non-explicit) level of the text indicate and place responsibility with or outside of involved individuals. The main conclusion of the syntax analysis performed is that Danielsson in his autobiography in fact does not use very many of the constructions described in the flow scheme, whereby it can be concluded that the syntax analysis in this case wasn?t so ?revealing?.
Evaluation of a Flow Cytometry Method for Identifying and Quantifying Fetal Red Blood Cells in Maternal Blood
Hemoglobin is an oxygen binding protein in erythrocytes. Hemoglobin is composed of four polypeptide chains. During the fetal stage the type of hemoglobin called fetal hemoglobin (HbF) dominates. After birth HbF is replaced by adult hemoglobin (HbA). HbF persists in concentrations less than 1%.
Headhunting : Rätt "man" på rätt plats?
Syftet med denna studie var att undersöka unga idrottares upplevelser i en topprestation.Studiens frågeställningar var:· Vilka upplevelser har unga idrottare i en topprestation?· Upplever unga idrottare flow i en topprestation?· Vilka faktorer ligger bakom en topprestation hos unga idrottare? Utifrån syfte och frågeställningar valdes mätinstrumentet Flow State Scale-2 (FSS-2). FSS-2 består av ett påståendeformulär som mäter den totala upplevelsen av flow samt var och en av de nio dimensionerna av flow.Kontakt togs via telefon och mail med ansvariga tränare vid idrottsgymnasier för att finna unga idrottare med ett tydligt minne av en topprestation. Undersökningsgruppen blev 51 stycken unga idrottare, män och kvinnor i åldrarna16-20 år som utövat fotboll, ishockey eller orientering på elitnivå.Litteratursökning gjordes i bibliotekskatalogen tillhörande Umeå Universitet. Den funna relevanta litteraturen och artiklarna har legat till grund för denna studies bakgrundsdel. Påståendeformuläret FSS-2 visar att undersökningspersonerna, i sin topprestation, hade en stark upplevelse av inre tillfredsställelse, tydliga mål, koncentration på uppgiften, känsla av kontroll och balans mellan skicklighet och utmaning.