Sök:

Sökresultat:

353 Uppsatser om Chemical precipitation - Sida 13 av 24

Brandsläckning och textil restvärdesräddning Hur saneras textil efter en pulversläckning?

This bachelor thesis discusses firefighting and the use of portable fireextinguishers in the salvageof historic artefacts focusing on textiles. It also looks into the use of multi-purpose dry chemicalextinguishers in a textile context and the impact the actual dry-agent has on textiles afterfirefighting.Literature studies, interviews and tests on different textiles were carried out to write this thesis.During the tests textiles were exposed to the dry agent and also to dry agent plus water toinvestigate the difference in residue. After vacuumcleaning it was clear that when the textile wasexposed to dry agent and water it was almost impossible to remove the chemical without rinsingin water.By examining the residue left on the textile using SEM it was possible to see if a textile was aswell decontaminated after vacuum-cleaning as it looks to the eye. We know that the dry agentoften consists of ammonium phosphate which acts corrosively on many materials and one canassume it damages textiles as well after longer exposure.Buildings housing cultural collections are vulnerable as we cannot easily replace ruined materialwith new.

Effect of low light intensities on dairy cows? behavior

The animal welfare act in Sweden states that dairy cows need to have at least a dim light present at night, but there are no recommendations for what intensity the light should have. It is unknown how cows perceive and react to low light intensities and earlier studies on this topic are limited. Red light as night light has also been suggested, based on the cows? inability to perceive red light. This have however been questioned. The aim with this study was to investigate how four different light intensities affect dairy cows behavior.

Förändring av nitratläckage och växtproduktion från låglänt jordbruksmark vid en ny reglering av vattennivån i Mälaren

The water level of Lake Mälaren has been regulated since the 1940?s. A recentinvestigation suggests that the current regulation needs to be adjusted in order toprevent a decline in water level, salt water from infiltrating from Lake Saltsjön,and risk of floodings. In addition to these preventions, the new regulation couldpotentially effect the natural environment and agriculture practices in the lowlands that surround the lake. The new regulation proposal calls for an increase invariations in Mälaren?s water level during seasons, while the annual mean waterlevel will remain the same.

Klimatfaktorers inverkan på granbarkborrens svärmningsintensitet i Medelpad

The spruce bark beetle (Ips typographhus) is one of the 25 000 species of insects in Sweden, an insect of great economic importance because it can alone terminate forest of high value. During the past decade, insights of climate change received with increasing attention. If the future brings a milder climate in the north and therefore a longer growing season, one would think that it would only affect the forestry to the better? Yet in recent time, outbreaks after storm felling seems to occur more frequently. The Spruce bark beetle ruins millions of cubic meter of Norway spruce (Picea abies) in Sweden alone, with more frequent storm felling and a larger amount of wind thrown threes in the forests there will also be room for an advancing reproduction.

Micro plastics in the oceans and their effect on the marine fauna

Small pieces of plastic, termed ?micro plastic? in the oceans derive mainly from degradation of big plastics such as beach littering, but also from sources of direct emission from e.g. beauty scrubbers and synthetic sand-blasting. These micro plastics are ingested by marine animals ? mistaking them for plankton ? or via prey.

Sjuksköterskors arbetsmiljö inom slutenvård och äldreomsorg : En litteraturstudie

AbstractThe aim of this study was to illuminate and collect existing research from the beginning of the 21 st century about nurses work environment in institutional and elderly care in Sweden.A literature review was made by analyzing eleven scientific articles. The result showed mainly information about nurses work load. The information dealt with high work demands, too much responsibility, shortage of staff, time press and stress. Furthermore nurses reported a lack of co-operation between staff and management. An important part in nurses? work was appreciation from colleagues, management, patients and relatives.

Identifiering av deponerat material i en deponi samt metodikförslag för upprättande av vattenbalans.

Högbytorp is Ragn-Sells? largest waste facility and it is located north of Stockholm. There is an old landfill still in use, but at the end of this year it will be closed. The waste deposited on the landfill can, through decomposition, give rise to a large amount of methane gas, which is an energy rich gas that can be used for heat and electricity production. To receive a relatively large amount of gas, the decomposition requires a high moisture content in the waste.

Påverkan från den förväntade klimatförändringen på tillväxten i norra Sveriges skogar : En litteraturanalys

This is a literature review of how the climate change affects the forest growth innorthern Sweden. The temperature will rise about 5 °C with the largest increase in thewinter season (December - February) and the CO2level in the atmosphere is expected tobe doubled. Precipitation patterns will change and increase with 25-35 % and theprecipitation will be in form of rain rather than snow. Today the forests in northernSweden are entirely dominated by coniferous stands. This may shift with the climatechange and results in a larger number of deciduous trees, preferably birch will becomestronger and grow better and faster.

Storjuktan ? Rekonstruktion av ett sekels kvicksilverbelastning. : En undersökning av kvicksilverkoncentrationer i daterat bottensediment.

The aim of this study was to examine the current and historic mercury(Hg) load of the lake Storjuktan due to its recent exposure to a local potential source of Hg in form of the Sulphide mine Blaikengruvan(2006) and an earlier potential sources of Hg-load, the damming of the lake(1960s). Sediments were extracted using a HTH-sampler, freeze-dried, and analyzed for tot-Hg, LOI and activity of 210Pb and compared to samples extracted prior to the opening of the mine(2006). Constant initial concentration (CIC)-dating model was used for dating the samples. Low levels of Hg (100ng/g) were found throughout the lakes sediment. The highest levels of Hg(220ng/g) was detected at a depth of 4-5cm dating back to the mid 1970:s, suggesting that increased levels of atmospheric Hg rather than damming of the lake has caused the increase of Hg.

Kemikalier på förskolor : En studie om hormonstörande ämnen och medvetenheten hos förskolepersonal

Chemicals in preschools - a study of endocrine disrupting chemicals and awareness among preschool teachers The purpose of this study was to investigate endocrine disrupting chemicals that have been shown in preschools and also the preschool teachers? awareness of these chemicals. There were two methods used for completing this study; a literature study and a practical study. The literature study was made by researching on the internet and in books. The practical study was performed by sending questionnaires to all preschools in Kiruna municipality to study awareness among staff.

Åre kommun och klimatförändringar : En studie kring hotet mot Åre kommuns vinterturism och dess anpassning till framtida klimatförändringar

Today?s climate research shows that the climate may increase its temperature. One sector that is being threatened by global warming is the winter tourism of the Swedish municipality A?re. Tourism is an important economical source of income in A?re and is now threatened by a shortened winter season.

Fuktens påverkan på utegipsskivor under byggtiden

This thesis is a study of humidity at Knauf Danogips external plasterboard. The study is performed at the building project Kv. Maskinen in Jönköping in cooperation with NCC Construction AB and Knauf Danogips. The measuring was performed during five winter/spring months to see how the weather influenced the plasterboard.The measuring was performed at a small two-storied building and a larger fourstoried building. From the buildings` placement were a couple of measuring dots selected and to get a good result was the dots located in the four cardinal points.

Effekten av Bisfenol A (BPA) på hanråttors (Rattus norvegicus) reproduktion

Today evidence exist that environmental chemicals deteriorate male sperm quality and that testicular cancer is increasing. Bisphenol A (BPA) is a chemical with estrogenic effects used in the manufacture of polycarbonate plastic and are found in, for instance, plastic boxes, feeding bottles and food containers. Much of the research on how men's reproductive ability is influenced are performed on rats. This review article complies how male rat reproduction is affected by BPA as a model for humans. Studies have investigated how sperm are affected, hormonal changes during reproduction and how reactive oxygen species (ROS) affects sperm.

Establishment and evaluation of a Barley starch isolation method with focus on representability

The high viscosity of barley material makes starch isolation problematical using regular methods established for cereals. An adjusted starch isolation method has been set up for barley, based on fractionation and purification. The focus is on attaining truly representative isolates of six flour samples selected for widely differing characteristics within the research program BarleyFunFood (BFF). Beside establishment of the method, this diploma work aspires to serve the BFF with isolated material of sufficient yield valid for further starch characterisation. A pre study was conducted evaluating available wet mixing equipment, experimental conditions and mode of procedure.

Validation of realtime-PCR of Fusarium avenaceum for detection in wheat

Mould is a common contamination in cereals. The growth of mould can stimulate mycotoxins production andsome of which at critical concentrations cause health problems in humans and animals. Fusarium is one of thefungus species that has been found in crops and can cause major problems for farmers such as reduced harvestand economic losses. A group of Fusarium species, Fusarium avenaceum, Fusarium poae and Fusariumtricinctum express a mycotoxin, enniatin. The limited information available today about enniatin-forming fungiis that they grow out on fields of wheat in colder climates.

<- Föregående sida 13 Nästa sida ->