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50 Uppsatser om Oxide - Sida 3 av 4

Barns upplevelse av lustgasbehandling : En intervjustudie

Syftet med denna deskriptiva kvalitativa intervjustudie var att beskriva barns upplevelser av lustgasbehandling. Urvalet består av sex barn i åldern sex till fjorton år som behandlats med lustgas vid procedursmärta, akut eller planerat, på barnsjukhusets akutmottagning eller allmänna specialistmottagning. Intervjuerna analyserades med kvalitativ innehållsanalys. Alla barnen upplevde annorlunda kroppskänslor eller abstrakta känslor som inte nödvändigtvis var obehagliga under lustgasbehandlingen. Samtidigt som flera av barnen beskrev en typ av frånvaro var de flesta medvetna om omgivningen och till viss del händelseförloppet.

Temperaturens och den fotosyntetiskt aktiva strålningens effekt på avgång och inlagring av kol på en dikad torvjord

The decomposition of organic carbon in drained peat soils is a major source of carbon di-Oxide in Sweden. A big part of these drained peat soils are used in agriculture and it is a big challenge to slow down their decomposition. It has earlier been thought that less tilling and higher water table levels would decrease the activity of soil microbes and thereby the decomposition, but recent experiments has showed that this has little or no effect. In this bachelor thesis a field experiment was made on drained peat soil with ley, outside Björklinge, Uppsala municipality, Sweden. The experiment was carried out in May 2011. The objective was to develop a method to examine how the net exchange of carbon diox-ide from plant covered peat soil is affected by temperature and photosynthetically active radiation (PAR).

Jordbruksdränering, kostnader och genomförande :

Underdrainage is a costly investment but often a necessity to maintain rationalized plant cultivation, one can also see underdrainage as insurance to successful plant cultivation. Late ripening crops, low yield and difficult tillage cultivation are examples on an insufficient drainage. (Kvarnemo 1983) A drained field rise in land price and the scheme of the tiled drains is seen as a value item. The interest for underdrainage among the farmers follows with shifting economic situations within agriculture and has for long time been low. A big part of the Swedish tiled drainage systems is since 1930 and ahead. Many of these tiled drainage systems need to be replaced or complemented. The life length of one tiled drainage system varies with maintenance but can still remain in good function after 75 years with correct management.

Syrgasdelignifiering av magnesiumbaserad sulfitmassa med magnesiumbaserad alkali

Syftet med arbetet var att undersöka hur olika reaktionsbetingelser skulle påverka syrgasdelignifieringen av en sur sulfitmassa. De betingelser som undersöktes var utbyte, slut-pH, viskositet och kappatal. Massan som användes kom från Nordic Paper Seffle och alkalit som användes var magnesiumoxid. Syrgasdelignifiering av massan gjordes  i autoklaver i ett PEG bad där tid, temperatur och alkalisatser varierades.Resultaten visar att alla utbyten låg mellan 90-97% och att även de mest aggressiva betingelserna bara gav en viskositets reduktion på 260 enheter, motsvarande 19% av den totala viskositeten.Slut-pH för syrgasavluten hamnade mellan 6,5-9,4 beroende på alkalimängd och temperatur under delignifieringen. Slut-pH minskade när mängden alkali hölls konstant men temperaturen varierades mellan 110-140°C.Kappatalet för massan kunde effektivt reduceras från ett startvärde på 23,4 till ett slutvärde på under 5 med en temperatur på 140°C, alkalisats på 10 kg/ODT och en tid på två timmar utan större förluster av vare sig viskositet eller utbyte.En ovanligt resultat som upptäcktes under arbetet var att delignifieringen tappade i effektivitet med ökad alkalimängd och detta samband gällde vid alla betingelser.En teori om detta kan vara att jonstyrkan i lösningen gör att fibrerna i massan drar ihop sig och att syrgasen får svårare att reagera med ligninet..

P?verkar intag av ?gg niv?er av trimetylamin-N-oxid i blodet? En systematisk ?versikt

Syfte: Syftet med denna systematiska litteratur?versikt var att unders?ka det vetenskapliga underlaget kring om regelbundet intag av ?gg p?verkar niv?er av trimetylamin-N-oxid (TMAO) i plasma hos vuxna. Metod: En litteraturs?kning genomf?rdes i databaserna PubMed, Scopus och Cochrane Library 25 januari 2023. Inklusionskriterierna var vuxna ?18 ?r, intervention best?ende av ?gg eller ?ggula, kontroll best?ende av ?ggsubstitut/?ggvita/habituell kost/annat livsmedel som inte inneh?ller ?ggula, utfallet TMAO i plasma och studiedesign RCT. Artiklarna skulle vara skrivna p? engelska eller svenska.

Livscykelanalys av en ekologisk bomullsskjorta - miljöpåverkan från vagga till grav

This study includes a life cycle assessment, LCA, on an ecological produced cotton shirt for the company Reflective Circle, which designs ethical and ecological clothes.Initially were cotton farming and textile production studied to gather basic knowledge about the processes. Since this shirt is being ecological produced in the whole production chain, we studied what an ecological production means, but also how a conventional production works. When this was done we could start to discuss the differences and similarities between the production of the shirt and general conventional production.When the LCA was first initiated, the main focus was on the green house gas emissions from the manure at the cultivation. Thereafter the process steps such as picking, ginning, carding, spinning, weaving and sewing were being studied. The picking is done by hand, but the rest of the processes are handed by machines which consumes energy.

Vad är ?rätt? gjutkvalitet? Hur uppnås det?

Ever since ABB has begun diecasting their rotors instead of permanent mold casting it,variation in the quality of the cast has arisen. Diecasting is performed in three differentmachines, M1, M2, M3 with 400, 660 respectively 800 tons of die locking pressures.The aim of this thesis is to answer the following questions:What is the ?right? cast quality? How is the right quality achieved?For sizes 160-180 solutions will be proposed that consider eccentricity between thelaminate and the short circuit ring as well as elimination of the thin Al film that appearson the outer periphery of the rotors.Through considering the statistic material the most often diverging rotor type has beenidentified and one of the actual rotors has been sent to a laboratory to be analyzed inorder to establish the current defects. The result of the analysis shows that there areplenty of gas- and Oxide-porosity.It has been proved that every time the dies temperature decreased below 120°C thecontent of gas porosity increased. It is due to rapid solidification of metal that flowsthrough the ?cold? laminate.It has confirmed that enhanced porosity in squirrel cage causes high impedance in therotors.

Spårtaxisystem i Uppsala

An increased awareness about the global warming has created a demand for more information on how the climate is affected by different activities.This master thesis was initiated by Tricorona, a Swedish company that offers its customers analysis and calculation of their climate impact. Tricorona also supplies climate neutralisation with CERs, in accordance with the Kyoto protocol and controlled by the UN. This work demands updated emission factors for greenhouse gases. An emission factor gives information about the greenhouse gasintensity of a service or a product [kg CO2-eq./ functional unit].The purpose of this thesis is to examine how electricity, district heating, hotels, taxis, food and materials affect the climate and how emission factors for these areas can be calculated.This was done by reviewing and comparing different studies and by interviewing experts. The information was evaluated and recommendations on calculations and emission factors were made.The consumption of energy is the main source of greenhouse gas emissions for district heating, electricity, hotels, taxis and materials.

Diesel Dubbelbränsle Teknologi

The work covered in this report includes a literature study of the diesel dual fuel technology(hereinafter referred to as DDF). The literature study covers earlier work that has been doneregarding the use of compressed natural gas (CNG) and diesel in a DDF system. Moreover a onecylinder research diesel engine was fitted with a CNG fuel system for experimental testing. Theinstallation of the engine and the test cell is described. Results from the tests are presentedcovering emissions, heat release and pressure traces from the DDF-concept.During the literature study it was found that most research was related to heavy duty dieselengines.

Analys och beräkning av emissionsfaktorer för växthusgaser

An increased awareness about the global warming has created a demand for more information on how the climate is affected by different activities.This master thesis was initiated by Tricorona, a Swedish company that offers its customers analysis and calculation of their climate impact. Tricorona also supplies climate neutralisation with CERs, in accordance with the Kyoto protocol and controlled by the UN. This work demands updated emission factors for greenhouse gases. An emission factor gives information about the greenhouse gasintensity of a service or a product [kg CO2-eq./ functional unit].The purpose of this thesis is to examine how electricity, district heating, hotels, taxis, food and materials affect the climate and how emission factors for these areas can be calculated.This was done by reviewing and comparing different studies and by interviewing experts. The information was evaluated and recommendations on calculations and emission factors were made.The consumption of energy is the main source of greenhouse gas emissions for district heating, electricity, hotels, taxis and materials.

ALK?RR - K?LLA ELLER S?NKA F?R V?XTHUSGASERNA METAN OCH LUSTGAS? Empirisk studie av v?xthusgasutbyte i kustn?ra alk?rr p? den svenska V?stkusten.

Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon habitats also contribute to coastal carbon sink capacity.

Sjuksköterskors uppfattningar kring lustgasadministrering till barn vid smärtsamma procedurer : - en kvantitativ studie

Bakgrund: Inom va?rden fo?rekommer det ofta sma?rtsamma procedurer i form av behandlingar och underso?kningar. Dessa procedurer kan vara obehagliga fo?r barn vilket go?r sma?rtlindring till en viktig del av pediatrisk va?rd. Lustgas a?r ett bra alternativ till barn pa? grund av att den har lugnande effekt, inte kra?ver na?gon ytterligare sma?rtsam procedur som na?lstick och har snabb och kortvarig effekt.

Ärtrev som substrat för biogasproduktion : En litteraturstudie och rötning i labbskala

Until 2020, 49% of Sweden's use of energy must derive from renewable sources. Greenhouse gases must as well decline with 40% compared to 1990 as a part of Sweden's 16 environmental objectives. Biogas is part of the effort to achieve these objectives, but as the demand for biogas increases, more substrates are needed to meet the demand. The purpose is to investigate the conditions for pea residue as substrate by performing lab-scale mesophilic digestion with different fractions and notch lengths and then to summarize pea residue as a substrate for biogas production. During anaerobic digestion, 1000 ml bottles were used as reactors for digestion.

Glödskalsrensning på göt med varierande tvärsnitt

På Ovako i Hofors, framställs stål via götgjutning. Göten har ett kvadratiskt tvärsnitt som varierar mellan 300 och 700 mm. Dessa transporteras från stålverket, till valsverket för uppvärmning. Varpå de varmvalsas till färdiga ämnen. Under tiden i ugnen när göten värms upp, Oxiderar järn och andra legeringar och bildar glödskal.

Styrdokument för kontorsbyggnation ur ett ekologiskt hållbarhetsperspektiv : Aspekter och argument

The construction and real estate industry represents a significant part of Sweden's total impact on the environment and mainly affects the following national environmental objectives: reduced climate impact, a good built environment and a non-toxic environment. By establishing internal rules, companies within the industry can reduce their environmental impact. SMT (AB Sandvik Materials Technology), a part of the industrial group Sandvik AB, has set a target that during 2014 develop a guiding document with special consider to the environmental impact during construction of office buildings, that they establish at the Swedish regional capital Sandviken, for both internal and external tenants. This study therefore aims to clarify which environmental aspects that the construction and real estate sector mainly are responsible for, and therefore should be part of a guiding document for a company for establishing office buildings, and to present arguments regarding the use of such a document. The study is based on literature studies and personal contact with other companies, in the form of e-mail conversations and a telephone interview.

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