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517 Uppsatser om Particle concentration - Sida 15 av 35

Uppfyller BIM förväntningarna som arbetsmetod för broprojekt?

The purpose of this work is to design and construct a device able to measure the mechanical attrition of oxygen carrier particles. Those particles are used in chemical looping combustion and in the present situation there is a lack of knowledge in how the attrition process work and in which extension. To find already tested solutions trying to answering this problem a literature study wascarried out and the best solution found was the so called Grace-Davison Jet-Cup method. This method is supposed to emulate the attrition caused by a cyclone separator and its advantages are that it is possible to use small test amounts, 5-10 g, and a thirty minutes long test will be enough to acquire useable results. An device was designed based on the Jet-Cup method with some slight modifications.

Implementering av Patientsimulator för Anestesimaskiner

In order to facilitate testing of anesthesia machines a patient simulator has been required by Maquet Critical Care AB. A patient simulator has been developed to reduce expensive and time consuming animal experiments and temporary lab arrangements. The patient simulator has been developed and designed to simulate human lungs with regards to anesthetic uptake, production of carbon dioxide and heating and moisturizing exhaled air.The system comprises a container and a test lung to simulate the volume and the dynamic of the human lung. The simulation of uptake of anesthetics has been implemented by pumping a fraction of the gas from the container through a bypass circuit with an active charcoal filter that adsorbs volatile anesthetics. The flow through the bypass circuit is generated by a pump and is controlled by a linear valve.The resulting performance of the patient simulator has fulfilled the requirements.

Skogen i barnlitteraturen : Kan den fungera som en källa till naturvetenskaplig kunskap?

The amount of various phosphorus (P) fractions in the sediment and the relationship between the amount of P and sediment particle size were investigated in a constructed wetland southwest of Linköping. Furthermore, the possible correlation between clay content in the sediment and distance from the inlet was investigated. Sediment samples were collected along three transects from the inlet to the outlet, with six samples in each transect. In order to measure the soluble P, an NH4Cl extraction was done. This was also analysed for total soluble P after oxidation with peroxodisulphate.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Naturlig förekomst av arsenik och avskiljning av arsenik från grundvatten : test av olika filtertekniker avsedda för enskilda brunnar

During the last few years the presence of high arsenic (As) concentrations in ground water has been of major concern both internationally and in Sweden. Much evidence has been reported about toxic effects caused by arsenic. The carcinogenic effects and the possibility to measure the toxic impacts at low concentrations made the World Health Organisation (WHO) to reduce the guideline value from 50 to 10 ?g l-1 in 1993. In Sweden the corresponding reduction was implemented in 2003. Several surveys in Sweden have shown that high arsenic concentrations may occur in ground water.

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.

Utvärdering av den gröna smileyn inom livsmedelsinspektion : En intervju och enkätstudie i Halmstads kommun

With a growing population on earth the amount of end-of-life vehicles (ELVs) and other scrap steel increases. The European Directive 2000/53/CE? requires a minimum of 95 % reuse and recovery and 85 % re-use and recycling no later than 1 January 2015, for end-of life vehicles. This imposes a need for more efficient recycling and recovery. Despite this shredder residue (SR) is commonly land filled.This report investigated the magnetic fines residue generated at Stena Metall shredder facility in Halmstad, Sweden.

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).

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.

Våtmarken som renare av dagvatten

Eight healthy 3-day-old foals were given repeated injections of trimethoprim-sulfadiazine intravenously for 3 days, at a dosage of 15 mg/kg bodyweight (2,5 mg trimethoprim and 12,5 mg sulfadiazine). Blood samples were collected prior to each administration and for the following 24 hours after last administration. Serum concentrations of trimethoprim and sulfadiazine were measured and the pharmacokinetics for the substances were studied. The elimination half time (t½) and clearance (ClB) for trimethoprim and sulfadiazine for the foals did not diverge from adult horses. According to these data it is possible to assume that the same dose interval and dose can be used for foals as for adult horses.

Asymmetrier i travhästars rörelsemönster vid långsam och snabb trav

Eight healthy 3-day-old foals were given repeated injections of trimethoprim-sulfadiazine intravenously for 3 days, at a dosage of 15 mg/kg bodyweight (2,5 mg trimethoprim and 12,5 mg sulfadiazine). Blood samples were collected prior to each administration and for the following 24 hours after last administration. Serum concentrations of trimethoprim and sulfadiazine were measured and the pharmacokinetics for the substances were studied. The elimination half time (t½) and clearance (ClB) for trimethoprim and sulfadiazine for the foals did not diverge from adult horses. According to these data it is possible to assume that the same dose interval and dose can be used for foals as for adult horses.

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.

Upprepad intravenös administrering av trimetoprim-sulfadiazin hos neonatala föl

Eight healthy 3-day-old foals were given repeated injections of trimethoprim-sulfadiazine intravenously for 3 days, at a dosage of 15 mg/kg bodyweight (2,5 mg trimethoprim and 12,5 mg sulfadiazine). Blood samples were collected prior to each administration and for the following 24 hours after last administration. Serum concentrations of trimethoprim and sulfadiazine were measured and the pharmacokinetics for the substances were studied. The elimination half time (t½) and clearance (ClB) for trimethoprim and sulfadiazine for the foals did not diverge from adult horses. According to these data it is possible to assume that the same dose interval and dose can be used for foals as for adult horses.

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.

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