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336 Uppsatser om Chemical Vapour Deposition - Sida 10 av 23

Uran i dricksvatten : litteraturstudie om reningsmetoder samt pilotförsök med jonbytesteknik

Uranium (U) is a naturally occurring component in bedrock and under the "right" conditions it can dissolve and move into the ground water. Since many people in Sweden depend on drilled wells as their main drinking water supply, they may be exposed to the uranium in the water. Radioactive radiation is not the major concern associated with naturally occurring uranium. It is rather the chemical properties of uranium that make it a potential danger to human health. Uranium is proven to have toxic effects with respect to the functioning of the kidneys.

Möjlig kvittblivning och eftermarknad av ridbaneunderlag - topplager

The aim of this study is to find information about what to do when riding arena footings are worn-out. Especially, the surface layer of riding arena footings is very interesting because of its importance of giving grip in every step for the horse, as well as shock ab-sorption. Generally, surface layers are containing several different parts in order to achieve desirable properties. These different parts can consist of organic material or in-organic material (mostly gravel). Gravel and many other materials in the top-layer are environmental friendly, and therefore, easy to get rid of.

Kemisk karaktärisering samt nedbrytning av process- och avloppsvatten vid SCA Ortvikens pappersbruk

During pulp and papermaking process a huge amount of water is used. The wastewater contains a large amount of pollutants and has to be treated before it reaches the recipient. In March 2004 a new bleaching plant was started up at SCA Graphic Sundsvall AB, Ortviken?s paper mill using peroxide. The production of bleached thermo mechanical pulp and thus the load to the wastewater plant increased.

Geografiska informationssystem för studier av polyaromatiska kolväten (PAH) : undersökning av djupvariation i BO01-området, Västra hamnen, Malmö, samt utveckling av en matematisk formel för beräkning av PAH-koncentrationer från ett kontinuerligt utsläpp

At the end of August 1999, the local government council of Malmö city decided thatthe area known as Kvarteret Bilen would be made available for the European HousingExhibition 2001 (Bo01-mässan). Kvarteret Bilen extends over approximately 80hectars and includes the western parts of the Western Harbour area (Västra hamnen)of Malmö.Kvarteret Bilen as a whole, but especially the western sections of this area, the socalledBo01 section, has been the subject of heated discussions. This is mainly due tothe fact that the ground in question has proven to be contaminated to a certain extentby different chemical compounds. Investigations undertaken during 1998 showed sporadically high concentrations forespecially one chemical group: polycyclic aromatic hydrocarbons (PAH).The first part of the paper describes the use of a mathematical equation (Fetter 1994)to calculate the concentration of PAH from a continuous discharge at a given time byemploying Geographical Information System (GIS). Even the constraints of theequation are discussed, as well as the consequences that follow as a result of usingGIS.The second part of the paper focuses on the connections between the content ofcarcinogenic PAH in Kvarteret Bilen and the ground water level and type of fillingmaterial.

Allanblackia stuhlmannii ? a tree under current domestication: what are the soil requirements?

Allanblackia is a genus of trees that grows in the rainforests of West, Central and Eastern Africa. Its big fruits contain seeds very rich in oil which has been used by local communities for cooking and making soaps. The native stands are threatened by overexploitation and the demand for the oil is much greater than the supply. Domestication programs, aiming at introducing the trees to small holder agroforestry systems, have been started for some of the species. The main aim of this study was to investigate the soil requirements of Allanblackia stuhlmannii in terms of chemical and physical parameters, as revealed by the soil conditions in native stands. Another aim was to see if these varied along an altitudinal transect.

Alternativa drivmedel : Vilket alternativt drivmedel uppfyller bäst Försvarsmaktens behov?

This essay is written within my education for Technical Officer in the Swedish armed forces. The essay describes the alternative fuels that the Swedish armed forces can make use of if the supply of fossil fuels is insecure. The alternative fuels that are described and compared are; Synthetic diesel, Organic diesel, Methanol and Ethanol. The essay describes the process of producing the alternatives, the need for modification and the economics for each alternative. The alternatives are compared and assessed for their ability to secure the supply of fuel to the Swedish Armed Forces.

Nitrat i dricksvatten : jämförelse av nitrathalter, mellan åren 1975 och 2005

Ronneby Miljö- och hälsoskyddskontor ville genom undersökningen få information om nitrathalter ienskilda dricksvattenbrunnar inom kommunen, med bakgrund av den nya miljökvalitetsnormen.Riktvärdet för nitrat är 50 mg/l. Halter som överstiger detta bör inte ges till barn under ett års ålder pågrund av risk för methemoglobinemi. Jämförelsen skulle ske mellan områden präglade av jordbrukrespektive skogsbruk, samt mellan grävda och borrade brunnar. Jämförelsen skulle även ske över tiden,mellan 1975-1990 till 2005. Urvalet av provtagningspunkter baserades på en sammanställning frånbefintligt arkiv samt efter en annons i dagspressen.

Modellering av indunstning på Södra Cell Mönsterås

Evaporation is a part of the chemical recovery department at wood pulping mills. The purpose of evaporation is to remove water from the black liquor, which makes the liquor combustible. The process is very energy demanding, and having a well-functioning model of the system is of greatest interest. The model can then be used to study energy consumption and to test different control strategies. Two models have been developed during the master thesis.

Wallenius waters AOT luftrenare

This bachelors thesis was made forWallenius Water AB to develop a basisfor an Airpurifier prototype. Wallenius Water isone of the world's leading environmentaltechnology companies engaged inchemical-free water treatment based onUV-radiation. The thesis aim was toproduce a basis for a prototype that canbe used in three applications:Standalone, RAS systems and ventilationsystems. The work includes anintroductory description of the theorybehind AOP technology based on aliterature review on the subject. Asurvey of products currently on themarket and a product specification hasbeen used as the basis for thepreparation of a number of concepts inthis report.

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.

Nitrat i dricksvatten : jämförelse av nitrathalter, mellan åren 1975 och 2005

Ronneby Miljö- och hälsoskyddskontor ville genom undersökningen få information om nitrathalter ienskilda dricksvattenbrunnar inom kommunen, med bakgrund av den nya miljökvalitetsnormen.Riktvärdet för nitrat är 50 mg/l. Halter som överstiger detta bör inte ges till barn under ett års ålder pågrund av risk för methemoglobinemi. Jämförelsen skulle ske mellan områden präglade av jordbrukrespektive skogsbruk, samt mellan grävda och borrade brunnar. Jämförelsen skulle även ske över tiden,mellan 1975-1990 till 2005. Urvalet av provtagningspunkter baserades på en sammanställning frånbefintligt arkiv samt efter en annons i dagspressen.

Helicobacter spp. i digestionskanalen hos svenska katter : en metodologisk och klinisk studie

Following the accident at the nuclear power plant in Chernobyl in 1986, great volumes of137Cs were distributed over large parts of the former Soviet Union and Europe. Over Scotland,radiocaesium was deposited as wet deposition. Due to the relatively long physical half-life of30 years, there are still measurable activity concentrations in the natural environment. Thisstudy was made on two organic soils, Knockandy Hill and Rora Moss, situated in the easternpart of the central highlands of Scotland. At these two sites, studies on migration and transferbetween soil and plants were conducted.

Geokemin inom osorterade cirklar : Analys av tungmetallers distribution inom jordprofiler tagna från Abiskoområdet, nordvästra Sverige

The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr).

Tillverkning av mikronålar för medicinsk tillämpning

Transdermal drug delivery, besides painfulinjections with syringes, has long been associatedwith small size particle pharmaceuticals, which candiffuse through the skin. This method of drugadministration has only been applicable on a smallnumber of drugs, where active molecules are smalland delivery time should or can be long.Other drug delivery options are oral administrationand injection with hypodermic needles (ordinaryhospital syringes). In oral administration thestomach and liver tend to dissolve the drug and theeffect becomes more difficult to anticipate, anddrug delivery rates difficult to control. Hypodermicneedles are used as a mean of drug injectiondirectly into the bloodstream. This method ispainful and risks infection due to tissue damageand skin penetration.One way to get a painless non-damaging techniquewith high delivery rate that still can delivery largemolecules is to manufacture an array of microscopichollow needles and equip them with a pumping unitthat delivers the correct amount of drugs.This thesis shows the technique and possibility ofmanufacture micromachined needles using low costtechniques of Ion Track Technology (radiation ofheavy ions creates porous materials), electrolessdeposition (non-current activated wet chemistrymethod of depositing metal) and electroplating.

Klibbalens gödslingseffekt på volymproduktionen i ett blandbestånd av gran och klibbal : en simulering i Heureka

A secondary and a pioneer tree species can with advantage be included in a mixed stand to increase the use of sunlight. Nitrogen-fixing plants have been shown to increase the supply of nitrogen in the soil by, for example, litter fall. This deposition acts as a biological fertilization, which may be used by non-fixing plants. Alder is a nitrogen-fixing, pioneer tree species that loses its nitrogen-rich leaves late in the autumn. The aim of this study was to examine the effect on the total volume of production, when different proportions of nitrogen-fixing Alder were part of spruce stands.

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