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98 Uppsatser om Particles. - Sida 6 av 7

Hur uppnår vi god inomhusmiljö i förskolan idag?

Abstract:This thesis work has been conducted at the Real Estate Department in Halmstad.The department consists of a construction/project management-unit and an operation/management-unit.Like many other towns in Sweden, Halmstad has had a long lasting problem with indoor environment. Not at least at their preschools.Today they are constructing from current building regulations. They have learned from negative experiences which have occurred in the indoor environment in older buildings.Focus is now on healthy materials, like low emission value, energy efficiency and optimization of the building, but still with soft parameters such as cleaning, interior and choice of materials.The fixtures is provides by the real estate department and the furnishings are provides by the children and youth administration. Together they are trying to provide a great indoor environment.I have, together with the real estate department and the children and youth administration of Halmstad, investigated how to provide a good indoor environment in the preschools with small funds.In my thesis there is one theoretical part with a questionnaire survey of how the preschool staff is experiencing their indoor environment to determine where the problems often start. And a practical part with measurements to try and come down to a result that analysis the cause of the problems and also to make sure that the ventilation systems are fulfilling projected values.The measurements and the questionnaire surveys was made at Lokes preschool in Frösakull, Askens preschool in Oskarström and Gullbrandstorps preschool.There were some differences between the staff-responses at the three different preschools.At Askens preschool they feel that the premises are cleaned poorly.At Gullbrandstorps preschool they feel that the indoor-air is bad because they can´t open the windows.

Kalciums och magnesiums inverkan på arsenikavdrivningen i virvelbäddsugnen : The influence of calcium and magnesium on the expellation of arsenic in the fluidized bed furnace

In the fluidized bed furnace at Rönnskärsverken, Skelleftehamn, sulphur-containing ore concentrates are roasted in order to remove about 50% of the sulphur in the incoming ore concentrate. This occurs in order to reach the goal of a matte containing 55% of copper in the following smelting process. At the same time as the ore concentrate is partially roasted pollutions as arsenic, antimony and bismuth are expelled. Earlier made thermodynamic calculations of equilibrium suggested that calcium and magnesium form stable compounds with arsenic and thereby inhibit expellation of arsenic in the fluidized bed furnace, an element that is undesired. The purpose of this thesis work was to gain knowledge of the mechanisms behind the formation of these stable arsenic compounds.

137Cesium i myrsamhällen i Gävleborgs län 24 årefter Tjernobylolyckan

24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.

Ett rökfritt sjukhus? : Diatermirök och rökevakueringssystem

Bakgrund: Vid de flesta kirurgiska ingrepp används diatermi. Diatermi används dels för att skära i vävnad, dels för att koagulera blodkärl, och en adekvat blodstillning är avgörande för en säkeroperation. Vid användning av diatermi utvecklas en skadlig rök, diatermirök. Trots att evidens finns för att diatermiröken innehåller skadliga ämnen som kan orsaka kroppsliga symptom, förekommer variation i användandet av rökevakueringssystem. Syfte: Syftet med denna studie var att undersöka i vilken utsträckning rökevakueringssystem, för diatermirök, används. Vi ämnade även undersöka om det förelåg några skillnader mellan avdelningarna samt mellan de två yrkeskategorierna; operatör och operationssjuksköterska. Metod: Operationssjuksköterskor och operatörer från nio operationsavdelningar, vid fyra sjukhus i Stockholmsregionen undersöktes i en deskriptiv tvärsnittsundersökning, med kvantitativ ansats, med ett intervjustött frågeformulär.

Retention av tungmetaller i en anlagd våtmark : studier av Vattenparken i Enköpings kommun

The aim of this study was to examine the amounts of heavy metals in the sediment of a wetland constructed for stormwater treatment. The wetland is called Vattenparken and is located in the city of Enköping. The heavy metals which were analysed were Pb, Cd, Ni, Zn, Cu, Cr and Hg. The total metal concentrations were determined using HNO3 chemical extraction. From 8 sampling sites 5 sediment cores were taken.

Axellagring till Klasserare

GE Healthcare wants to investigate whether additive manufacturing would be an alternative method in their workshops in the Umea? plant. Additive manufacturing is called 3D printing in everyday language and manufactures details by building them up layer by layer in an automated machine. The purpose of this work is therefore to investigate how mature additive manufacturing methods are and how they could be used at GE.The work has been divided into three parts. The first section investigates how additive manufacturing would work in the production workshop at GE.

Vaccination mot Humant Papillomvirus - vem bör vaccineras?

Background: Infection with Human Papillomavirus, HPV, is one of the world's most common sexual transmitted infections. The virus causes genital warts (condyloma) but certain virus types can cause cancer. The most common cancer type caused by the virus is cancer of the cervix. Nowadays there is a screening program for women between 23 and 60 years of age where Pap smears of the cervix is taken to discover abnormalities at an early stage. Cervical cancer is very common all over the world and this screening program saves many lives, but not in the less developed countries since the screening program is too expensive.

Additiv tillverkning : Ett nytt alternativ inom tillverkningsteknik

GE Healthcare wants to investigate whether additive manufacturing would be an alternative method in their workshops in the Umea? plant. Additive manufacturing is called 3D printing in everyday language and manufactures details by building them up layer by layer in an automated machine. The purpose of this work is therefore to investigate how mature additive manufacturing methods are and how they could be used at GE.The work has been divided into three parts. The first section investigates how additive manufacturing would work in the production workshop at GE.

Igensättning av långsamfilter i Östby vattenverk i Kramfors : studie av påverkande faktorer

Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.The waterworks is a surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters.

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.

Syntes av hydroxyapatit/ nanocellulosa kompositer

Cellulose nanocrystals (CNC) are great candidates for composite materials. The reasons why CNCs are such attractive materials for them are due to their great mechanical properties, high aspect ratio and low density. On the other hand, hydroxyapatite (HAp) is a kind of calcium phosphate and a main component of bones and teeth. The purpose of the present study is to make oriented nano-sized composites with CNC and HAp. Although some researchers carried out to make CNC composites with HAp for biomedical materials, nano-sized and oriented ones haven?t been achieved yet.

Optimering av den kemiska reningen vid Fläskebo deponi

Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.

Bedömning av spermiemotilitet i färsk, kyld samt selekterad hingstsperma med Qualisperm :

This EEF-project is a part of a larger project at SLU, Division of Reproduction, Dept of Clinical Science, with the intention of developing and evaluating new methods for the assessment of stallion semen quality. Over the last 10 years there has been an increase in the use of artificial insemination with cooled semen in Swedish horse breeding. At the same time, foaling rates have decreased. This has lead to a need for new and better methods of assessing the quality of stallion semen. This EEF-project was based on an objective method to calculate motility, with QualispermTM, in fresh and cooled stallion semen, and after selection. Today sperm motility evaluation is mainly done subjectively by visual assessment with a light microscope, and the correlation between these motility results and fertility have varied.

Är Lerbodaälven verkligen en problemälv? : undersökning av fosforhalter

Lerbodaälven is a river in the municipality of Kil which, due to high phosphorus content is not meeting the requirements for good ecological status according to the Water Framework Directive. The purpose of this report is to investigate the causes for the high content of phosphorus that has been measured in Lerbodaälven between 1995-2010. Four questions will be answered in this report. 1. Does the sewage treatment work affect the phosphorus level in Lerbodaälven? The result from the time series analysis shows that the sewage treatment works have a small impact on the phosphorus level in Lerbodaälven.

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