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498 Uppsatser om Heavy metal polluted - Sida 8 av 34

Kemin bakom framtidens avgasrening : En studie av ureasönderfall under kvävgasatmosfär

The purpose of this work was to provide a better understanding of urea?s decomposition and byproduct formation in an SCR system on heavy trucks. In my experimental setup with TGA-DSC-FTIR (a combination of two thermal analysis methods and a method for gas phase detection), an FTIR method for urea in the gas phase was developed for the qualitative and quantitative determination of urea and its decomposition products. Chemicals such as urea, biuret, cyanuric acid and melamine of p.a. quality were used in this method development. Beforehand, there was no FTIR method available to detect these substances; hence, the aim of this work was to develop an FTIR method to understand the degradation chain of urea. The combination of TGA and DSC was used for analysis of different samples, where urea, biuret, cyanuric acid and melamine in varying amounts have been weighted in for various experiments in order to study the temperature at which a phase transition or reaction occurs, i.e.

Inventering av förorenad mark på LKAB´s industriområden i Kiruna, Svappavaara och Malmberget :

The county administration asked LKAB to make an inventory of possibly contaminated sites caused by their mining activity. The inventory should be performed according to the MIFO model, a method from SEPA which is used to assess a contaminated site. The first phase involves collection of information through interviews and site inspections and in phase 2 a general survey with field sampling is conducted. LKAB started the work with the first phase of the survey during 2003. During this project the information collected in Phase 1 was evaluated and 16 of the sites were chosen to proceed to MIFO Phase 2 (six sites in Kiruna, and 5 sites respectively in Svappavaara and Malmberget). The sampling of these 16 sites was performed during week 27 2004.

Inventering av förorenad mark på LKAB's industriområden i Kiruna, Svappavaara och Malmberget

The county administration asked LKAB to make an inventory of possibly contaminated sites caused by their mining activity. The inventory should be performed according to the MIFO model, a method from SEPA which is used to assess a contaminated site. The first phase involves collection of information through interviews and site inspections and in phase 2 a general survey with field sampling is conducted.LKAB started the work with the first phase of the survey during 2003. During this project the information collected in Phase 1 was evaluated and 16 of the sites were chosen to proceed to MIFO Phase 2 (six sites in Kiruna, and 5 sites respectively in Svappavaara and Malmberget). The sampling of these 16 sites was performed during week 27 2004.

Modellen och materialet

Tycho Hedéns Väg in Uppsala has evolved from being a through fare passage and highwayto the oversized road frame running through the city it is today. At the present time, dueto the relocation of the E4 highway east of Uppsala, Tycho Hedéns road creates a barrierbetween the north eastern area of Uppsala and the remaining parts of the city centre. Theroad is designed to endure heavy traffic and high speed limits, generating a surrounding urbanarea were inhabitants are complied to follow the standards set for a high traffic-accessibleenvironment. Furthermore, the heavy traffic has led to the turning of both urban roadsidesaway from the actual road. The aim of this project and proposal is to show the possibilities ofhow the innate features of Tycho Hedéns road can be used more advantageously to mend thecity area of Uppsala.

HUR KAN VI REDUCERA DEN INTERNA ÖVERGÖDNINGEN SAMT REGLERA ALGBLOMNINGAR FRÅN ATT NÅ EGENTLIGAÖSTERSJÖNS KUSTZON ?? : En vision om att återfå en balans i Östersjön genom att skörda algöverskott och använda biomassan som en framtida råvara.

The Baltic Sea is one of the world?s most polluted seas. Increased discharge of nutrients due to greater populations of people, together with a slow water exchange, creates great stress on the sea. Too much nutrients leads to increased growth of algae and causes problem in the ecosystem. Even if we reduce nutrient discharge the problem still exist in the ocean. When algae dies and sinks, more nutritional substances is produced called "internal eutrophication". This phenomenon will grow in the future due to a warmer climate and the problem is spreading towards the coastal zone, which is an important site for fish recreation. By removing the abundance of algae, the nutritional and toxic substances are reduced and the algae biomass can be a future resource for biofuel production..

Sha Jun

The agriculture in Sweden today uses chemical substances to control vermin, weed and diseases. This usage shows through polluted subsoil water and trace elements in the food we eat. There?s a risk that additional symptoms will arise in the future. Our product Sha Jun, developed in 2006-2007, is an attempt to try and minimize the need of chemicals in the agriculture. The idea started with the attempt to minimize the usage of pesticides on the cropland.

Vindfällning i naturliga och skapade bryn och kanter :

The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

Tycho Hedéns Väg : trafikrum blir stadsrum

Tycho Hedéns Väg in Uppsala has evolved from being a through fare passage and highwayto the oversized road frame running through the city it is today. At the present time, dueto the relocation of the E4 highway east of Uppsala, Tycho Hedéns road creates a barrierbetween the north eastern area of Uppsala and the remaining parts of the city centre. Theroad is designed to endure heavy traffic and high speed limits, generating a surrounding urbanarea were inhabitants are complied to follow the standards set for a high traffic-accessibleenvironment. Furthermore, the heavy traffic has led to the turning of both urban roadsidesaway from the actual road. The aim of this project and proposal is to show the possibilities ofhow the innate features of Tycho Hedéns road can be used more advantageously to mend thecity area of Uppsala.

Positiv särbehandling och kvotering

The purpose of the essay is to investigate SVT: s (Swedish Television) attitude to allocation of quotes and preferential treatment. In Sweden there is only one law, which allows preferential treatment ? the law of equal opportunities. This law prohibits discrimination between women and men. The profession of camera operator and editor have been viewed as masculine in accordance to heavy lifting and high technology, this considering being hindrance to women.

Detection of mutations in dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr) in Plasmodium falciparum in eastern Sudan

ABSTRACT: Commercial swab transport systems are used for collection and transporting of fecal and other microbiological samples. This system must maintain viability and contribute to survival of microorganisms during transport to the laboratory. Four swab transport systems have been compared, eSwab, ?- Transwab and fecalSwab, all three with flocked swabs, and Copan Venturi Transystem with rayon swabs. The study followed the recommendations from the Clinical Laboratory Standard Institute; document M40-A for recovery of Samonella, Shigella, Yersinia and Neisseria gonorrhoeae after storage for 0, 6, 24, 48 and 72 h at room- (22-25°C) and refrigerated (2-8ºC) temperature.

Comparison of four transport systems for enetric pathogens

ABSTRACT: Commercial swab transport systems are used for collection and transporting of fecal and other microbiological samples. This system must maintain viability and contribute to survival of microorganisms during transport to the laboratory. Four swab transport systems have been compared, eSwab, ?- Transwab and fecalSwab, all three with flocked swabs, and Copan Venturi Transystem with rayon swabs. The study followed the recommendations from the Clinical Laboratory Standard Institute; document M40-A for recovery of Samonella, Shigella, Yersinia and Neisseria gonorrhoeae after storage for 0, 6, 24, 48 and 72 h at room- (22-25°C) and refrigerated (2-8ºC) temperature.

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.

Riskbedömning vid Saltvikens kopparverk

AbstractAt Saltvikens copperindustry, which is located in the municipality of Oskarshamn, copper was refined from sulphiteore some hundred years ago. The ore underwent several steps in the process before the final product was received. These steps all had an influence on the environment through discharge of heavy metals. The area where the copper industry was located is today considered to be of specific national interest due to its valuable nature and cultural values, as well as its value for recreational outdoor activities. Therefore, it is important to determine the present level of contamination and if any transport of contaminants have occurred, and to identify the risks that are associated with the site both at present and in a longer time perspective.Thirtynine soil samples and 16 sediment samples have been analyzed.

Provtagning av trädkärnor för att bedöma föroreningsgraden av klorerade lösningsmedel i grundvatten

Chlorinated aliphatic hydrocarbons (CAH´s) were used widely within dry cleaning facilities and for metal degreasing until their toxicity was discovered. PCE is still used as dry cleaning liquid. Today CAH´s are found in soil environment at places where they have been used in the past. The CAH-concentration in trees growing on contaminated land has quite recently received attention as a cheap and effective way of assessing the extent of a CAH-contamination. The method has however, not been put into use in Sweden.The aim of the study has been to investigate whether the CAH-concentration in tree cores could be used to delineate the spread of CAH in a soil environment under Swedish conditions in different seasons.

Avena Sativa - En hyperackumulator? : En studie av havres kadmiumupptag

The aim of our research was to investigate if oat is capable of extracting cadmium to such extent that it is usable in decontaminating polluted soils. We grew oat in a hydroponic culture during 28 days in a controlled environment and a total of 30 plants were used. The nutrient solutions were contaminated with cadmium of ten different concentrations after seven days. After harvesting the plants, the roots were separated from the shoots, placed in separate containers and then turned to ashes. The cadmium content was measured three times per sample in an atomic absorption spectrometer.Our results indicate that the ability of oat to extract cadmium from a solution is linearly dependent of the cadmium concentration of the solution.

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