Avancerad sökning

Visar resultat 1 - 5 av 40 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Microplastics in the aquatic environment: Insights into biological fate and effects in fish

   Författare :Giedrė Ašmonaitė; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; microplastics; nanoplastics; plastic pollution; effects; fish; chemical mixtures; ecotoxicology;

   Sammanfattning : According to the United Nations, plastic pollution in the natural environment has been identified as one of the biggest environmental challenges of this century and has become a cause for an emerging international concern. It has been predicted that up to 12 million tons of plastic waste reach the aquatic environment annually. LÄS MER

3. 2. Catalytic Converters for Automotive Exhaust Applications. Flow Dynamics, Mass Transfer and Optimization

   Författare :Fredrik Ekström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TWC; optimization; exhaust; laboratory reactors; catalytic converter; catalysis; pressure drop; entrance effects; CFD; mass transfer; pulsations; flow distribution;

   Sammanfattning : In order to reduce emissions from vehicles powered by an internal combustion engine, an exhaust aftertreatment system is normally mounted on the engine. This aftertreatment system normally consists of one or several catalytic converters. LÄS MER

4. 3. Computational chemistry studies of UV induced processes in human skin

   Författare :Jonas Danielsson; Aatto Laaksonen; Villy Sundström; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photochemistry; Theoretical chemistry; Density functional theory; UV effects; TD-DFT; enzyme catalysis; DNA damage; Molecular dynamics; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : This thesis presents and uses the techniques of computational chemistry to explore two different processes induced in human skin by ultraviolet light. The first is the transformation of urocanic acid into a immunosuppressing agent, and the other is the enzymatic action of the 8-oxoguanine glycosylase enzyme. LÄS MER

5. 4. On some positive effects of swirling flow for the continuous cast mould billets

   Författare :Shavkat Kholmatov; Pär Jönsson; Simon Lille; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; swirling flow; round mould; divergent angle; aspect ratio; temperature distribution; velocity fluctuations; continuous casting of steel; mathematical modeling; CFD; Metallurgical process engineering; Metallurgisk processteknik;

   Sammanfattning : Continuous caster moulds are the last and most important stage in the steelmaking process, where inclusions can either be generated or removed. With increasing casting speed using conventional immersion nozzles critical problems, such as unstable bulk mould flow have been noticed. LÄS MER

7. 5. Developmental co-ordination disorder in pre-school children : Effects of motor skill intervention, parents' descriptions, and short-term follow-up of motor status

   Författare :Mia Pless; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Obstetrics and gynaecology; Developmental co-ordination disorder; follow-up; motor skill intervention; pre-school children; self-perceived competence; Obstetrik och kvinnosjukdomar; Obstetrics and women s diseases; Obstetrik och kvinnosjukdomar; pediatrik; Pediatrics;

   Sammanfattning : This investigation was undertaken to examine effects of motor skill intervention in children with motor difficulties consistent with developmental co-ordination disorder (DCD) diagnosed in child health care before school entrance, to analyse the parents' descriptions of their children, and to follow up the children's motor status in a short-term perspective. Thirteen studies on the effects of motor skill intervention were submitted to a meta-analysis (Study I). LÄS MER