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534 Uppsatser om Stone forming substances - Sida 7 av 36
Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon
Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques.
The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.
Behandlingsvåtmarkers reningseffekt på aktiva läkemedelssubstanser under vinterförhållanden : En studie av fyra svenska våtmarker för avloppsrening
Pharmaceuticals that are found in marine ecosystems are a threatening environmental concern, which is known to harm both animal and plant life. One of the reasons for this problem is that the waste water treatment techniques are not optimized to clear waste water from its pharmaceuticals contain. In this master thesis four Swedish treatment wetlands were studied, and their ability to reduce numerous pharmaceuticals in waste water. The four treatment wetlands that were studied were those in Oxelösund, Trosa, Nynäshamn and Eskilstuna. Two ecotoxicological tests and chemical analysis were used.
Genom skugga och sten
Through Shadow and Stone är ett projekt där textil och ljus samspelar i en textil utsmyckningsbelysning för att skapa en stämning på en offentlig plats och där en personlig upplevelse har varit utgångspunkten. Fokus i arbetet ligger på hur skuggbilder kan bidra till stämningen i rummet och hur man med hjälp av trikåteknik kan ta fram strukturer som kan framkalla dessa. För att nå resultatet har arbete med färg och form även varit ett viktigt element..
De bortglömda stenarna : om byars äldre gränsmarkeringar och rågångar i Ekeberga socken
This essay is about the hamlets´ older boundaries, i.e. boundary lines (?rågångar?) and boundary markers in the form of rocks, and an own survey of two hamlet boundaries in southeast Sweden. Many of the boundary rocks were subjected to unintentional damage or destruction that arose during forestry activities, the excavation of ditches, or road construction. Boundaries between hamlets sparsely populated areas were not clearly defined from the beginning, but were established initially in the form of boundary zones, that often consisted of wetlands, watercourses, or mountain heights.
Bestämning av syntetiska cannabinoider med gaskromatografi-masspektrometri
This thesis has been performed at Clinical Chemistry at Sahlgrenska University Hospital in Gothenburg. The purpose of the project was to investigate new and alternative ways to determinate synthetic cannabinoids by gas chromatography-mass spectrometry. Currently, the possibilities to quantify synthetic cannabinoids are very limited. This can lead to an increased use of synthetic cannabinoids as the risk of detection is low, which may be known by drug users. The synthetic cannabinoids are sold mixed with different herbs and have varying names like Spice Gold, Spice Silver, K2, Smoke and Pot-pourri.The synthetic cannabinoids analyzed were JWH-018 and JWH-073, which are commonly found in seized Spice material.
Skårby : En kultplats med lång tradition
The ancient site of Skårby, situated about twenty kilometres south of Stockholm, includes one very large cairn enclosured by a stone wall with a small cairn attached to it. Cairns are originally thought of as graves, but resent research shows that they are more likely to have been religious objects. The constructions are seated on a small hill with a view over the lake Bornsjön which used to be a bay of the lake Mälaren. This place has been the object of worship throughout the whole Bronze Age. Over the years the manifestation of the worship changed, but the place for it stayed the same..
Historiska emissioner av bly och arsenik till luft från Åfors Glasbruk och deras konsekvenser för miljön.
Åfors glasswork was a company which started in 1876 and closed in 2012 due to the bad economical situation in the company. After its closure, the glasswork left behind contaminated soil with different concentrations of heavy metals such as, arsenic from arsenic trioxide, a chemical used to remove bubbles during the melting of glass, and lead oxide, a chemical used in the production of crystal glass. Crystal glass?s production occurred under 1921-1971, but emissions of lead into the air from Åfors glasswork continued until 2011, because of the artist Bertil Valliens? artglas was made in Åfors glasswork from 1970?s and onwards.The aim of this study was to estimate how much lead (Pb) and arsenic (As) that were released by Åfors Glasswork into the atmosphere during the operational period of the glasswork in comparison with how much of lead and arsenic were purchased for the company. Added to the assistance of the data from National Archives the variations in the activities of Åfors glasswork could be shown.
Implementation av spridningsmodell i ArcGIS
The project involves implementing a finished dispersion model into ArcGIS. The goal of the tool is to show how dangerous and toxic substances will travel in the ground after long periods. The goal of the project is to understand GIS in general, what it is used for and gain an insight into how developing tools for ArcGIS is, what challenges might exists. Understanding the type of data that can be stored and accessed in ArcGIS a long with the tools and functionality offered by the system when using Python as the main language for development. A prototype of the tool is created..
Möjligheter och hinder för att utöka omfattningen av RoHS-direktivet
The RoHS Directive was introduced in order to restrict hazardous substances in Electrical and Electronic Equipment, EEE. It currently restricts the use of six hazardous substances/compounds; cadmium, lead, mercury, hexavalent chromium, PBB, and PBDE. The RoHS Directive currently includes category 1-7 and 10 in the categories of EEE listed in Annex 1A to the WEEE-Directive (Waste of EEE). The aim with the report is to investigate and elucidate prospects and obstacles to increase the scope of RoHS. This report mainly considers the inclusion of product categories 8 (Medical Devices) and 9 (Monitoring and Control Instruments).
INVERKAN AV HAVSF?RSURNING P? PROTONERBARA ORGANISKA F?RORENINGARAS EKOTOXICITET
Resulting from anthropogenic carbon dioxide emissions, average surface seawater pH is estimated to decline from today's approximately 8.05 to between 7.78 and 8.03 towards 2100. For ionisable organic pollutants, changes in pH can lead to a change in the degree of ionisation, which could influence the ecotoxicity of a compound by altering its bioavailability. In this study, potential changes in ecotoxicity of ionisable organic compounds resulting from ocean acidification are examined. This is achieved partly by conducting a literature review, analysing existing literature that investigates this relationship. Potential changes are also evaluated by examining marine ecotoxicity data for ionisable organic compounds on the watch list pursuant to Directive 2008/105/EC of the European Parliament and of the Council, as well as on the list of priority substances according to the 2022 proposal for amending the Water Framework Directive (2000/60/EC).
Relational Theory of Contract och företagsförsäkringsavtal
Forming teacher teams is currently the standard way of organizing teachers in Swedish Compulsory Schools. This is the result of a process that started in the 1970s.Traditionally the culture of teaching has been one of isolation. Once the door to the classroom is shut, what happens behind the door is up to the teacher to decide. Over the past thirty years a lot of time has been dedicated to making fundamental changes in the way teachers interact with their colleagues. Today the idea of teachers forming teams is generally accepted but still the core of a Swedish teacher?s job is that of a lone worker.
Upprepad administrering av trimetoprim/sulfadiazin till neonatala föl : plasmaproteinbindning och effekt på serumbilirubinkoncentrationen
Today most dosages used in horse medicine are based on studies in adult horses. Since there are differences between adult and neonatal horses with respect to different pharmacological parameters this can cause problems when administring drugs to neonatal foals. Neonatal sepsis is a common cause of morbidity and mortality in foals and aggressive antibiotic treatment is needed immediately when sepsis is suspected. In Sweden the combination of trimethoprim/sulphadiazine and bensylpenicillin is often used as the initial treatment. When administering drugs, interactions can occur between the drugs and endogenous substances.
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.
Ett verk blir kosmopolitiskt : Representerar Louise Bourgeois verk Maman någonting "universellt"?
The aim of this work is to give an example of how archaeoacoustics can broaden our understanding of archaeological remains and to further contribute to the almost non-existing research of ringing stones. With a theoretical discussion about sound from three different perspectives and by means of using different kinds of analysis, this essay will show that there are unknown relations between the three known ölandic ringing stones and the cultural landscape of Öland. Possible patterns in the placement of the stones and the possibility of the sound in this soundscape will be investigated. The essay will also suggest a resonant stone typology and discuss the necessity of one. Finally, the intention is also to shed new light upon the discussion on what the uses of the ringing stones might have been..
Järnåldersboplatser och historiska byar : En studie av agrara bebyggelsemönster i mälarbygder under 1500 år
Following paper deals with the questions about prehistorian and medieval settlements in the Mälar Valley and their relations to the historically known hamlets or single farmsteads from the 17th- and 18th-century cadastral maps. Models over settlement development through the period A.D 200 to 1700 done by geographers Ulf Sporrong and Dan Carlsson are tested and compared to the knowledge won by recent archaeological excavations. Is there a connection between the older settlements linked together by dry-stone walls and the late Iron Age settlements? Does the picture differ from the one presented for the Gotland region? How well are the general theories about different settlement development depending on basic natural conditions as for the potentials for cultivation and topography, corresponding to the physical remains? Are there other factors involved when the settlement structure takes its form?The methods that are used here constitutes mainly of a comparison between different locations in the Mälar Valley that has got a well known prehistory thanks to extensive archaeological excavations. Cadastral maps, soilmaps, topography maps and maps over ancient monuments are intertwined to the same map and analyzed through works in Geographical information systems.The results of this study reveal an interesting suspicion in the continuity-question through the Iron Age.