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114 Uppsatser om Gradient wash - Sida 1 av 8

Sänkta sjöars inverkan på ytvatten i Västerbottens kustland : Samband mellan sänkningsnivåer och vattenkemi i sjöar på sulfidrika sedimentjordar

Lake lowering in sulphide-rich areas is currently a major environmental impact for surface water. This study focuses on whether there is a relationship between a gradient of lake lowering and surface water impacts in areas of sulphide-rich sediments, in order to better understand their contribution of heavy metals and sulfuric acid. Also, is it a reasonable method to use the reduced lake area in order to quantify the gradient? The survey was conducted by collecting water samples from reference lakes and lowered lakes from south to north in coastal areas within the county of Västerbotten. Water samples were then analyzed for TOC, pH, conductivity, anions, base cations, alkalinity, acidity, sulfate, Al, Cd, Fe, Mn, Cu, Zn and Pb.

Miljöanpsassad metod för hjultvätt

In order to avoid harmful substances ending up at the municipal sewage treatment plants, it is important to purify the wastewater at the source. One such source is the wheel washers available in many tire garages which are used to wash the wheels on our vehicles when we change between summer and winter tires. It is important to wash the wheels before storage, to extend the tires lifetime. The purpose of this study is to find a green innovative solution for reduction of emissions of heavy metals at the source, so that the sludge from the sewage treatment plants can be used as fertilizer. The target is to find a wheel wash method which leads to compliance with the guidelines for car washers, and that also provides a better washing result than with the existing method.

Investeringskalkyl på självtvätthall för Vetlanda Vägkrog AB

Background and problem: Since the new law took place in 1999, it has been illegal towash a car with substances that can damage the environment on a paved street or on a driveway through a garage. This has conveyed to a new industry where more and more self-service car wash facility have opened around the country. Vetlanda Vägkrog AB has since 2012 been planning to install manual self-service car wash facility at the back of their restaurant business. The authors mission was to make an analysis in order to examine whether an investment of carwashes are lucrative enough for Vetlanda Vägkrog AB.Aim: The study's main objective was to analyze the profitability of an investment in a self-service car wash facility at Vetlanda Vägkrog AB, based on given data. The authors sub-aim was to clarify which factors in general that had played the greatest part in the establishment of a self-service car wash facility.Method: The authors have used an abductive approach in order to fulfill the aim of the study.

Tid kontra pengar : Goal-gradient effekt vid valet mellan nettonuvärdesmetoden och återbetalningsregeln

Syftet med denna uppsats var att studera om det finns en målgradient vid investeringsbedömning som medför en preferens för alternativ med kort återbetalningstid och snabba belöningar. Vi valde att genomföra denna studie med hjälp av en kvantitativ ansats, då vi genomförde ett experiment med studenter vid Blekinge Tekniska Högskola. Detta motiverar vi med att utifrån vårt syfte och vår teoretiska referensram, ger det oss störst möjlighet att generera ett intressant och relevant resultat. Vårt resultat visar tydligt att beslutsfattare föredrar att använda återbetalningsregeln före nettonuvärdesmetoden i en beslutssituation, och därmed ett fokus på tidsaspekten och när en investering är återbetald. 81 % av våra respondenter valde tidsalternativet i minst ett av de två casen.

Variation in protein precipitation and phenolic content within and among species across an elevational gradient in subarctic Sweden

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

Comparison between different freezing and thawing methods for human spermatozoa

Preservation of cells and tissues by freezing at temperatures below 70°C has led to new possibilities for the storage of germ cells for fertility preservation. During the freezing process problems might occur, the greatest being ice crystallization which can cause membrane destruction and thus cell death. To minimize this risk, solutions that reduce the freezing point can be added to reduce crystallization and increase survival rates. These solutions are called cryoprotectants. The best method for freezing is still not known.The aim of this study was to analyze the effect of various parameters on the survival rate of human semen frozen with liquid nitrogen.

Elementkoncentrationer i gran utmed en markfuktighetsgradient :

One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.

Vägparametrar och deras inverkan på trafiksäkerheten : Fallstudie på länsväg 360 Lycksele - Vilhelmina

The interaction between the driver, the car and the road is essential for the road safety. This case study focuses on the road condition and its effect regarding road safety issues. By studying and isolating the road condition aspect and its contributing role to the accident occurrence, the aim is to explore their relationship, as well as highlight the road parameters that are commonly associated with accident occurrence. This result will be used to develop and increase awareness of the impact of poor road alignment and poor road surface conditions on traffic safety, in order to prevent these accidents from occurring. The road parameters chosen for this study include side friction, cross slope and rut bottom cross slope, road texture, curvature, drainage gradient and rutting.The case study was limited to lv 360 in Va?sterbotten, where all accidents with an unclear cause of the accident were studied, between 2003 and 2012 were carefully studied and assessed based on the condition of the road at the time of the accident.

Tid kontra pengar - Goal-gradient effekt vid valet mellan nettonuvärdesmetoden och återbetalningsregeln

Syftet med denna uppsats var att studera om det finns en målgradient vid investeringsbedömning som medför en preferens för alternativ med kort återbetalningstid och snabba belöningar. Vi valde att genomföra denna studie med hjälp av en kvantitativ ansats, då vi genomförde ett experiment med studenter vid Blekinge Tekniska Högskola. Detta motiverar vi med att utifrån vårt syfte och vår teoretiska referensram, ger det oss störst möjlighet att generera ett intressant och relevant resultat. Vårt resultat visar tydligt att beslutsfattare föredrar att använda återbetalningsregeln före nettonuvärdesmetoden i en beslutssituation, och därmed ett fokus på tidsaspekten och när en investering är återbetald. 81 % av våra respondenter valde tidsalternativet i minst ett av de två casen.

Oljeavskiljare för biltvätt : Från idé till prototyp

This thesis describes the developmentof a device called "Oil Separator"which is used for washing vehicles andparticularly car washing. The devicedeveloped for Mr. Car Bilvård AB inUppsala, the company's work involvespassenger transport and courierservices. The company needs anexternal device that meets theenvironmental standards to wash theirown cars in the premises without theneed to modify or reconstruct on thepremises ground as the premises is ona leased contract.Work began with a preliminary study onthe literatures that describes boththe function and structure ofdesigning the device. A few interviewswith other car wash companies had beenimplemented, and some measurements.After collection of the necessaryinformation the specifications ofcustomer requirement was presented .With these requirements a fewconcepts was generated and weighedusing the Pugh matrix for conceptsselection for further development.The final concept was furtherdeveloped and a design has beenpresented.

Mesatorrhalt

AbstractDegree thesis Solid content in Lime Mud By Andre Flodin Process operator program ? Umeå University 17/6 ? 2014 Pages: 21A thesis was made on Billerudkorsnäs production unit in Karlsborg where lime kiln in the causticising department of chemical recovery plant does not meet the required production. Causticising department is the final step in the chemical recycling unit. There, the filtered green liquor is mixed with lime to recover the cooking chemicals used in the pulp factory. The cooking liquid is called white liquor.

Axial- och gradientkrympning hos golv på mark enligt Eurokod 2 : Sprickbredders beroende av betongkvalité, tvångseffekter och armeringshalt

AbstractConcrete foundation slabs are usually exposed to unilateral drying during the curing process. The unilateral drying causes an axial shrinkage and a concave curvature of the construction. The curvature results from the fact that the upper part of the slab is drying and shrinking faster than the lower part. This is called gradient shrinkage.A problem occurs when the slab is considered fully restrained by adjoining structural parts. The deformations caused by axial contraction due to the constant part of the shrinkage and the curvature caused by gradient shrinkage of the slab are then prevented by the fact that the slab is fully restrained.

Kromatinstabilitet som grund för kvalitetsbedömning av hingstsperma :

This study is part of a project to evaluate and develop metods to control the semen quality in stallions. The study was carried out in cooperation between SLU and Flyinge AB. The objective of the study was to analyse -if there are individual differences in sperm chromatin integrety between different stallions -if there is a correlation between subjectively evaluated sperm motility and sperm chromatin integrity -if sperm chromatin integrity is changed after selection of the semen with a centrifugation method through the silica-spheres, gradient or a single-layer, i.e to use the chromatin integrity analysis as a method to evaluate the selection method. The use of chilled transported semen has increased a lot during the last 10 years, especially among the Swedish warmblood breed. Because the foaling percentage has decreased with the increased use of chilled transported semen, there is a need to develop methods to control the sperm quality. Evaluation of the chromatin integrity could be one way to evaluate the quality of the semen. Chromatin is the DNA in the nucleus of the sperm.

Torkningstekniker i den preoperativa handdesinfektionen - en experimentell studie

ABSTRACTIntroduction: Preoperative hand disinfection aims to prevent surgical site infections. After the preparing hand wash, drying is performed using an aseptic technique. It?s important to dry hands thoroughly in order to achieve the full effect of the alcohol based hand disinfection. Due to the lack of a evidence-based guideline on this procedure, the hand drying techniques differ among operating theatre nurses, depending on which technique seen as the most appropriate.

Utveckling av mothållssystem till valsar

This Master Thesis is a product development project that has been carried out incooperation with Metso Paper Sundsvall AB. The task has been to develop a holdingsolution that generates force between two rolls and to evaluate the new solution withrespect to functionality, manufacturing, structural stability, costs, assembly etc. Theroll holding solution is a system that is part of a rollpress. The rollpress is used towash and dewater pulp. The existing solution creates forces that have to be absorbedby the gable of the press.

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