Sök:

Sökresultat:

11514 Uppsatser om Laboratory material - Sida 4 av 768

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.

Förbränning av pellets framställda av defibrerad granråvara :

Fuel pellets are in Sweden mainly produced from sawdust and cutter shavings. Before the pelletising process the raw material is dried to attain consistent moisture content and ground up in a hammer mill. In the densification process (pelletising) the ground material is forced through holes in a rotating die. This heats up the wood particles which cause them to soften and self bond. After the process the pellets are cooled, sieved and bagged. The milling process creates a wide range of particle sizes.

Avbördningskapacitet för Traryd kraftverk: en modellstudie vid dimensionerande flöde

Sydkraft Vattenkraft AB owns and operates the Traryd hydropower plant, located in the river Lagan in the southern part of Sweden. The gravity dam is classed according to RIDAS guidelines (Hydropower Industry Dam Safety Guidelines) as a class 1B dam. This means that the dam must discharge a class 1-flow which has a return period of 10 000 years. The inflow into the dam has been calculated in an earlier report to 495 m3/s, with a waterline at an elevation of 126, 3 meters above sea level. The gravity dam has a discharge system with two rectangular weirs, which results in a smaller discharge than the necessary 495 m3/s.

Texturbestämning genom fält-, pipett- och hydrometermetoder :

Texture is an important soil property and accurate particle size analysis of soil texture is therefore crucial. There are a number of well-established and newly developed methods available for determining soil texture. In order to compare the results of these methods, the differences between them must be determined. The difficulties, problems and differences regarding texture class determination were examined through a study performed on forest soil samples. The study compared different methods (pipette, hydrometer and field methods) and two types of dispersing agents (sodium pyrophosphate and sodium hexametaphosphate (calgon)) commonly used for particle size analysis.

Hydrolys av primärslam för förbättrande av biologisk fosforreduktion vid behandling av hushållsavloppsvatten [Hydrolysis of primary sludge for enhancement of biological phosphorus removal in household wastewater]

Hammarby Sjöstad is a new district of southern Stockholm built with focus on reduced environmental impact by recirculation of materials and sustainability. The environmental goals aim to cut the water consumption by half and a separate storm water treatment. Thus, the wastewater will be more concentrated and will originate from the households only. The Sjöstad project includes the idea of a local treatment plant for the household wastewater. To evaluate this possibility, Sjöstadsverket, an experimental treatment plant was constructed.

Hydrauliken i Ångersjöns fosforfällor : bestämning av flödesvägar och åtgärdsförslag för optimal fosforbindning vid avloppsrening med reaktiva filter

Discharge of untreated wastewater leads to unnaturally high levels of nitrogen and phosphorus in rivers, lakes and the sea, which results in unbalanced ecosystems with eutrophication and lack of oxygen. Part of the phosphorus in surface waters is coming from on-site wastewater treatment from scattered households with unsatisfactory purification. Blast furnace slag is a by-product from iron production, and has in laboratory trials showed good phosphorus binding capacity. To test blast furnace slag as a reactive filter media for phosphorus separation in a full scale experiment, a wastewater treatment plant has been built behind the picnic area at Ångersjön alongside the road E4 in central-eastern Sweden. The plant contains two parallel lines, one with blast furnaces slag and the other with Filtralite-P as phosphorus sorbent. Both filters have showed decreasing phosphorus purification effect with time in spite of a low wastewater load.

Matematik+andraspråkselever = matematiksvårigheter? : Varför och vad kan lärarna göra?

The purpose of my examination work was to show the need for support for students with another mother-tongue than Swedish, so that these students would be able to get through mathematics tuition better. To achieve this purpose, I chose to start from the perspective that presented itself at interviews with two class teachers and two mother-tongue supervisors. I also chose to use the qualitative research interview as study method, as I tried to understand those informing me in a thorough and in-depth way. In my study I have had a sociocultural perspective as starting point where the conceptions teaching, language and communication, support and individualizing are central for the development of knowledge. The questions for my study during this process were as follows: What difficulties, according to the teachers interviewed can occur for second language students in mathematics? What ways and methods of working do the teachers chosen give priority to, so that   the second language students` results in mathematics will improve? The results from my interviews show that the difficulties with mathematics for second anguage students can be perceived as being dependent on a combination of reasons, where amongst other things language plays a central part.

Ethics and Animal Experimentation in the Laboratory. A Critical Analysis of the Arguments for"Animal Rights"and"Animal Equality"

Growing up as a child, we had a Dog. To us, it was like a means to an end. That is, hunting other animals for food and for protection, with no special care and treatment given to this animal. Butas days passed by I began to witness a wind of change against such actions. I was made to understand that we were committing two crimes-: using the Dog as a means to an end (for hunting and for eating animals).

Claw and leg lesions in preweaning piglets : a comparative study of piglets reared on structured polyurethane coating and piglets reared on concrete floors

Floor surface in pig facilities can have an impact on animal welfare and pig health, as it can cause the pig physical damage and thereby increased risk of infectious diseases and lameness. The development of pig housing systems has resulted in a decreased use of bedding. It seems hard to find the optimal floor in farrowing pens, as it must suit both the sow and piglets. The floor friction needs to be adequate to avoid slips and at the same time should the floor be non-abrasive. Abrasions and lesions caused by the floor are not only causing the animal suffering, but are also negative from an economical aspect.

Utvärdering av visuella observatörer förhålkameror och panoramakameror

SammanfattningExamensarbetet är utfört vid Fujita laboratory på Tokyo Institute of Technology.Detta examensarbete beskriver teori och bakgrund av en visuell observatör somhar forskats på vid Fujita laboratory.Att använda visuella sensorer, det vill säga kameror, kan bland annat hjälparobotar att agera autonomt i okända och i dynamiska miljöer. Syftet med envisuell observatör är att estimera ett objekts position i förhållande till robotensamt hur objektet och roboten rör sig gentemot varandra, med hjälp av bildensom fås från kameran.Syftet med examensarbetet har varit att studera teorin bakom observatören ochhur den anpassas till två olika kameror, en hålkamera och en panoramakamera.Fokus har legat på att utvärdera observatörerna experimentellt samt jämföra deolika kamerorna. Observatören för de båda kamerorna modelleras och simulerassedan och testas slutligen experimentellt. Examensarbetet innefattar även denbildbehandling som behövs för att göra experimenten möjliga att genomföra.I slutet av examensarbetet jämförs observatörerna för de olika kamerorna medavseende på korrekthet i estimering, robusthet mot parameterosäkerheter samtkänslighet för störningar.Resultaten visar att observatören för panoramakameran är känsligare förstörningar än den för hålkameran. Resultaten visar också att observatören förhålkameran är känsligare för parameterosäkerheter.

Aktivering av en dissolvingmassa med enzymer före en konventionell viskosprocess

In conventional viscose manufacturing, a large amount of carbondisulfide is consumed. This amount has to be decreased to keep the production cost down and to reduce the environmental impact. The purpose with this work was to show if an enzyme treatment of a dissolving pulp could increase the degree of substitution in the viscose so that the amount of carbon disulfide consumed in the process could be decreased. Previous investigations by Kvarnlöf (2007), Engström et.al. (2006) and Henriksson et.al.

Utvärdering och jämförelse av olika fälttester för fotbollsspelare

Different field tests are currently used in a wide extent in different levels of soccer teams. To be able to assess the players? physiological status the tests must have high validity, reliability and external validity. Many different tests have been developt, but currently only five of these tests are most commonly used: Yo-Yo intermittent recovery test (YIRT), Yo-Yo intermittent endurance test (YIET), Multi-sprint-test, Beep-test and Cooper-test. Presently there is no definitive conclusion regarding which of these tests is most suitable for soccer players.

Evaluation of lithium-heparintube analyses performance

Today, some kind of laboratory results is required for around 70% of the diagnostics and follow-ups for diseases. In many of the cases the time from sampling to a result is very critical. Therefore the discussion of how to improve this situation has begun. For many analyses serum has been the routine choice for a long time but now it is disputed. After blood collection in a serum tube it is essential to wait 30-60 minutes before centrifugation and analysis of the sample, a long time for someone in an acute state.

Studie och riskanalys av sulfidleror i Uppsala stad

Most of the city of Uppsala rests on postglacial clay with a varying content of sulphur. The sulphur occurs naturally in the clay in reduced form as sulphide and the clay is for that reason usually called ?sulphide clay?. Excavation during construction activities gives rise to large amounts of excavation material, of which the sulphide clay is a considerable part.When the clay is exposed to air and water, an oxidation of the sulphides occurs which may produce an acid leachate and the mobilisation of heavy metals bound in the clay or underlying material. The aim of the work has been to improve our understanding of the behaviour of sulphide clays and produce a basis for risk assessment in the future handling of excavation material with high sulphide content.

Matematiksvårigheter : En studie om fyra pedagogers erfarenheter kring matematiksvårigheter med exempel på pedagogiskt arbetssätt

For many years, I have tried to understand why students end up in difficulties in mathematics. As a future teacher, it is extremely important to have knowledge of the various factors that leads to difficulties in mathematics. As a teacher it is obvious to meet the students who find mathematics a difficult subject, and, therefore it is necessary to have a broader knowledge of how to respond and support these students. According to Ahlberg, number of students with mathematics difficulties is increasing every year, therefore, it is important to help students and organize a supporting school environment that promotes and encourages learning (Ahlberg 2001, p. 104-105).

<- Föregående sida 4 Nästa sida ->