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527 Uppsatser om Serum-concentration - Sida 15 av 36

Är det möjligt att använda SCR-rening av rökgaserna vid inblandning av avfall i biobränslet?

Waste appears to be a low-cost fuel compared to biofuel. This Masters thesis was conducted for Vattenfall Utveckling AB and deals with how waste in the fuel affects the performance of a SCR-catalyst. Different mechanisms of deactivation were surveyed, focusing on the poisoning mechanism. A literature study was carried out, which was used as a reference when analysing the results.Small samples (9x2x2 cm, 64 pieces) cut out from a full-scale unused honeycomb catalyst were exposed up to 1500h in two different combustion plants, Johannes in Gävle (co-combustion) and Högdalen in Stockholm (waste-combustion). The activity was measured mainly at 300°C but also at 250, 350, 375 and 400°C.

Stem injection of different nitrogen forms into young Norway spruce

This master thesis has been a pilot study preceding a forthcoming project of a larger scale with the long term objective to separate the direct effect of added nitrogen on soil processes from indirect effects via trees. The aim of this study has been to investigate the allocation of nitrogen following direct injection of liquid solutions into the xylem of 40 year old Norway spruce. The field site is located at Flakaliden (64°07?N, 19°27?E), approximately 60 km northwest of Umeå, Sweden. A total of 18 trees were selected for treatment, equally divided between three treatments, potassium nitrate, glutamine and water (control).

Borrelia burgdorferi : metodutveckling och tillämpning avseende odling och resistensstudier mot komplement, särskilt interaktion med faktor H

The genus Borrelia is a widespread, pathogenic pest and the causative of among others borreliosis or Lyme disease. The vector for the bacteria is the hard tick, Ixodes ricinus and the infection is transferred through a bite. Untreated, Borrelia may cause arthritis, heart damage or neuroborreliosis. Infection is made possible through different strategies for avoiding the body?s complement system.

Kostrelaterade riskfaktorer : En litteraturstudie gällande IGF-1 och ökad risk för prostatacancer

Bakgrund:Den dominerande cancerformen hos män över 75 år är prostatacancer. Kosten har en påverkan på många sjukdomstillstånd och på senare tid har man undersökt misstankarna kring om höga nivåer av IGF-1 kan öka risken för att utveckla prostatacancer. IGF-1 finns naturligt i kroppen men hormonet finns bland annat också i vissa livsmedel så som mejeriprodukter. Syfte:Att granska tillgänglig evidens gällande samband mellan höga nivåer av IGF-1 och prostatacancer, samt att om ett samband går att finna, undersöka om en kostrekommendation kan göras för att sänka nivåerna av detta hormon i kroppen och på så vis minska risken för utveckling av prostatacancer. Metod:Systematisk litteraturstudie.

Inverkan av juverhälsostatus på variation i mjölkens sammansättning och innehåll av utvalda inflammatoriska markörer

SAMMANFATTNINGMastit är den vanligaste och mest kostsamma sjukdomen hos mjölkkor. Enligt statistik från Svensk Mjölk har cirka 65 % av alla kor i Sverige mastit någon gång under en laktation. Subklinisk (utan märkbara symtom) mastit utgör det största problemet. De är svåra att upptäcka då även mjölken ser normal ut, vilket resulterar i att den hamnar i tanken och levereras till mejeriet. Mjölk från kor med mastit har ett ökat celltal samt försämrad kvalitet och sammansättning vilket i slutändan medför sämre betalt för lantbrukaren.

Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering

Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.

Mätning av partikelmassa i avgaser från en dieselmotor

This master thesis was a continuation of a previous study in the diesel exhaust characterization, which is part of the academical work embedded in the EMIR-1 project. The main objective of this thesis work was to finish the installation and make the proper modifications of the particulate mass measuring system located in one of the engine test cells at KTH, in order to be able to measure the mass of the particles from the exhaust of diesel engines.This experiment requires a diluted flow sample from the exhaust that should be sent to the device that makes possible the measurement of particle mass, called TEOM. In the first stage of this project, the objective was to study and make the proper modifications in the existing KTH diluter because there were several problems to obtain a constant dilution ratio from it during tests.This modifications were made and it resulted in a great improvement in the maximum inlet and outlet flow that this diluter can handle. Therefore another modification is proposed for controlling the inlet exhaust flow so it will be possible to regulate the dilution ratio and make it constant along a wide range of engine loads and speeds.The second and most important stage was to make particulate mass measurements possible by analyzing the frequency signal from the TEOM device. The idea was to obtain the frequency of oscillation from the tapered element in the TEOM, and therefore with the proper correlations, be able to predict the particulate mass concentration in the exhaust flow from the engine.An electrical problem in the TEOM circuit was detected and corrected, so the signal that carries the frequency from the TEOM can be analyzed properly.

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.

Megalitgravarna i öst : Megalitgravar i förhållande till bopats och landskap på Öland

The aim of this essay is to see if there are any relationship between the four Megalithic graves, and the newly excavated dwelling site in Resmo socken on Öland. The Megalithic graves on Öland consist of one dolmen and three passage graves. Is the excavated site a settlement? Since there are no signs of housing constructions, I will also explore other possible purposes of the site. What surprised the excavators was the concentration of pits that contained ceramics, flints and burned bones.

Effekter av tidiga reflektioner vid musikreproduktion

In this project the focus has been on the system for recombination at Oskarshamn 2. The recombining systems have on several occasions switched paths due to low pressure before the last ejector that?s feeding the recombiner. Of the mentioned reason, events and several measuring points have been analyzed in this report since the installation of the recombining systems.In order to prove theories and demonstrate what may be the cause of this problem, we used heat balance calculations by the program Probera. Using the program, we can demonstrate that the catalytic process does not reach the desired temperature with the amount of combustible substance.

Psykosocial arbetsmiljö och ledarskap: en kvalitativ studie om anställdas upplevelser av den psykosociala arbetsmiljön med fokus på ledarskap

Previous research has shown that the psychosocial work environment and leadership have a significant influence on the employees work satisfaction. Still there is much to explore regarding the employees experiences about these two subjects. A qualitative approach was used in this study to increase the understanding of the employee´s experience of psychosocial work environment and leaders role affecting it. Eight semi structured interviews were carried out at two organizations with four interviews in each place. The data was transcribed and a meaning concentration analysis was conducted.

En udda fågel i den för övrigt homogena bankflocken : En fallstudie av Oktogonen

The purpose is to describe and analyze Handelsbanken?s proftit share system Oktogonen and to investigate how it affects the motivation among the employees and management.The method qualitative case-study has been used. Both primary and secondary sources act as a foundation for the thesis. The primary sources are based on eight qualitative interviews. The empirical material is completed with appropriate theories.

System 348 - Rekombinator : Analys av reglerproblematik vid O2

In this project the focus has been on the system for recombination at Oskarshamn 2. The recombining systems have on several occasions switched paths due to low pressure before the last ejector that?s feeding the recombiner. Of the mentioned reason, events and several measuring points have been analyzed in this report since the installation of the recombining systems.In order to prove theories and demonstrate what may be the cause of this problem, we used heat balance calculations by the program Probera. Using the program, we can demonstrate that the catalytic process does not reach the desired temperature with the amount of combustible substance.

Fysiologi och beteende hos golden retriever i hemmiljö och under en testsituation

To fit into our society the dogs of today need a good mentality. To investigate their mentalitydifferent behavior tests have been developed. The tests are useful tools in the selection ofbreeding animals as well as for working and companion dogs. To counter the demand for atest that could be suited for all kind of dogs, regardless of their future function, the mentalitytest Beteende- och personlighetsbeskrivning hund (BPH) was developed. BPH consists ofseven subtests that expose dogs to various situations that can be found in everyday life, suchas meeting an unfamiliar person, sudden noises and suddenly appearing objects.The aim of this study was to find out if there are differences in physiological values betweenindividuals, validate the behavior observations during BPH and get aware of how the dogsexperience the situation.

Hur fungerar en glaselektrod?

To understand the glass electrode needs knowledge from more than one level. The construction ofthe glass electrode is one part, an other is the composition and structure of glass. The Nernstequation have an important role, but also the sources of errors in the analysis and the calibration ofthe glass electrode. Focus for this article is how the glass electrode really works and how Gibbs freeenergy made the potential dependent of the concentration of H+and gives the logarithm to thefunction. Nikolskii's ion exchange theory starts to explain the question about how the potentialcreates and Baucke's dissociation mechanism made it more explicit.

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