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281 Uppsatser om Metal contamination - Sida 4 av 19

Rening av metallhaltigt avloppsvatten : En teknisk/ekonomisk utvärdering av reningsmetoder för metallhaltigt avloppsvatten

This Master?s Thesis aims to investigate and assess the methods used to decrease the discharge ofmetals, primarily copper, from the water purification plant at Assa Industries plating factory inEskilstuna.Literature studies of the purification methods precipitation, ion exchange, evaporation, reverseosmosis and electrolysis has been done to appraise the adequacy of the technique. Thesetechniques are commonly used for purification of industrial waste water.Assa has four plating lines: the Trumline, the big Zinkline, the new Zinkline and the Decorativeline. The new Zinkline is the most modern of the four lines and purification is done byrecirculation over an ion exchange unit. The demand for fresh water is thereby heavily reduced.The Trumline, the big Zinkline and the Decorative line all use older techniques.

Empirisk studie av den radiella förspänningskraftens variation i klassiska skärskruvförband

In this study, the pre-tension force in an insert screw connection are examined in order to establish a greater understanding of the system and to facilitate the process of making new metal cutting tools. Certain especially significant design variables such as the offset, the length of the contact thread and the shank length above the threaded hole, are selected to be closely examined. A comparison of the influence on the pre-tension force between threaded holes made with a worn, versus new, threading tool is also involved in the experiment. The study is limited to handling the screw sizes M2,5 and M3,5. The results show that a regression model, with good approximation, can be fitted to the measured values.

Geokemisk undersökning vid Rävlidmyrgruvan, Västerbottens län : provtagning, analys och förslag till åtgärder

The mining industry, in terms of ore excavation and metal production, is and has been important to the Swedish economy. In connection with the ore excavation process, large amounts of partly sulphidic waste are produced. When the metal sulphides are exposed to air and water they are eventually oxidised, which leads to the formation of acidic water with high concentrations of metal cations and sulphate ions, so called Acid Mine Drainage (AMD). This water may reach the nearest surroundings and cause negative environmental effects. By covering the waste with soil or water, the oxidation process can be minimised. At the Rävlidmyran mine in the county of Västerbotten open pit mining took place between 1951 and 1991.

Investigation of tissue factor mRNA levels in human platelets using real-time PCR

Tissue factor (TF), a 47 kDa glycoprotein, is the initiator of the extrinsic pathway of blood coagulation and consequently of the upmost importance when damage to blood vessel occurs. The source of TF in circulation has been investigated. However, the source of TF is still not clear. One theory is that platelets express and increases the expression of TF after stimulation and the aim of our report was to investigate whether platelets really are a source for TF in circulation.Using specific primers for TF mRNA, platelets in plasma from healthy volunteers and from patients suffering from cardiac infarction were analyzed by using real-time polymerase chain reaction (PCR). Gel electrophoresis was performed after amplification of TF mRNA to verify the results.The samples were negative for TF when using real-time PCR and the few positive all had cycle threshold (Ct) values above 35.

Så långt inuti, näst intill borta

Through wing pattern, posture and movement, a harmless moth of the family Brenthia imitates an eight-eyed jumping spider. When an octopus of the species Thaumoctopus mimicus sense danger it can alter its appearance to that of a venomous sea snake. They are both drawing attention to themselves. Nevertheless, and because of this, they are protected. The mechanism is called mimicry.

3D-visualisering i markprojekteringsprocessen

The thesis has been made for NCC Teknik in Gothenburg. The NCC Corporation is one of the largest leading companies in Scandinavia within the construction industry. NCC is active throughout the whole construction process, where one part is to carry out soil investigations prior the construction of various buildings, for example residential buildings. NCC Technology wants to visualize the samples taken at the construction sites in 3D for clients, authorities and also internally to show in a simple and understandable way how contamination is spread out in the soil.The thesis includes the area of Limhamns läge in Malmö, previously an industrial area. The area has previously included a concrete factory and the contamination from that factory has lingered in the soil.

Ljus i butiksmiljö : Upplevelsen av ljus och exponering av produkter

This thesis examines how to improve the exhibition of products within retail for clothes and gift articles. The purpose is to investigate and test how light sources and different directions of light affect how the products are perceived regarding their exhibition. Our question formulations are:To what degree does the level of light in combination with the background of the interior design of a shop affect whether a product is perceived more or less attractive?What can we recommend to make the exhibition of products more attractive? From our observations shops nowadays have relatively high levels of light when they expose products on vertical areas. We have looked on the recommendation from ?Energimyndigheten? in order to see what they think is important when designing retail lightening.

Salmonella prevalence in the poultry feed industry in Pakistan

Abstract One of the leading causes of food borne infections in the world is due to Salmonella by con-suming poultry products including eggs and meat. According to US Food and Drug Admin-istration (2009), 2 to 4 million cases of Salmonellosis in humans occur every year only in US. Salmonella causes wide range of diseases with enteric and typhoid fever, food poisoning, di-arrhea and gastro-enteritis. Many serotypes of Salmonella do not have host specificity and cause disease in all kinds of animals and humans. Salmonella has capability to modify accord-ing to the changing environment and it can develop resistance against routine elimination practices of sanitation, chemical treatments and antibacterial drugs. Newly established poultry industries in Pakistan are confronting various infectious diseases including Salmonellosis while in Sweden Salmonella prevalence in animal products con-sumed for humans is extremely low.

Ett re(el)lt hot? Om elprisets betydelse för investeringar inom basindustrin

The aim of this thesis is to investigate the correlation between the price of electric power and investments within the Swedish basic industry. Using regression analysis, the authors test for correlation between the electricity prices and the basic industry, defined as the pulp and paper industry, the mining industry, the steel and metal industry and the basic chemical industry. Moreover, five variables found in the literature on investment decisions are being used as a means of comparison. The results suggest that the electricity price affects the investment decisions within the basic chemical industry as well as the steel and metal industry. On a more abstract level, this thesis contributes to the understanding of one of the properties of the Swedish GDP..

Instrumentbordets sterilitet

Background: Postoperative infections are a serious patient safety problem and affects about 3 % of all patients undergoing surgery. The consequences are prolonged hospital stays, high social costs, increased use of antibiotics and impaired quality of life for the patient. It has been shown that postoperative infections may be caused by contamination already in the operating room. Today we know that there is growth of microorganisms on the instrument table´s top, but there is a research gap about the instrument table's edges.Aim: To examine if the sterile drape on the instrument table´s edges are sterile after finished surgery.Method: Contact plates are printed on strategically selected areas on the sterile drapes top and edges. In the pilot study, a total of 51 cultures were taken at the end of three operations which lasted over three hours.Results: Growth on the top surface and the edges of the sterile drape were detected.

Bland brons och järn - spåren av metallhantverk från Bornholms yngre järnålder.

This essay is about Late Iron Age settlement and its production. I want to define the nature ofthree different workplaces on Bornholm, Denmark, and compare them. My aim is to see if itis possible to define a workplace through the traces of the craftsmanship. Several materials areselected in this essay and the analysis provides different perspective on workplaces in the LateIron Age in Scandinavia. The results of the analysis between the three workplacesAgerbygård, Baggård and Kanonhøj shows that Baggård have more traces of melting of bronsthan any other of the places.

Musik och Livsstil : En studie om ungdomar och hårdrock

In the following study I probe the social world of hard-rock music. By conducting interviews with four young male enthusiasts of this music I try to develop a general picture of this social world, as well as of the basic elements on which this particular subculture is constructed. The identity of a hard-rocker is based upon a number of factors beyond just a preference for that music. Throughout the interviews I encountered many implicit norms that one must followed in order to be able to see oneself as a true hard-rocker. I also found that from the respondents? perspective, the mainstream culture has, throughout the history of metal music, used various ways to counter the spreading of this genre.

Heavy metal rostar aldrig: om riffets roll inom hårdrocken

Detta examensarbete gjorde jag för att försöka ta reda på vad ett riff kan vara, och vilken roll riffet har inom hårdrocksmusiken..

Reglering av matarsystem vid höghastighetskapning

Today small metal parts are mass-produced as for example rollers in cylinder bearings. At high velocity cutting the metal is cut with a great force in a scissor-like device. Both precision and repeatability is important to be able to guarantee good quality, but from an economical point of view it is also important to keep a great manufacturing capacity. The part of the process that is most time consuming is when the metal bar, that is about to be cut, is fed to the right position. Therefore it is interesting to examine if the time used for positioning can be reduced.

Bacterial contamination of eggshells in deep litter floor systemsand conventional cages in Jordan

This study was carried out in Jordan with the purpose to investigate the bacterial microflora of egg shells from cage systems and from deep litter floor systems. Another aim wasto get a general impression of the hygiene, at farm level, of egg production in Jordan andthe factors affecting it.Eggs from two cage systems and three floor systems were analyzed, regarding bacterialcontamination of the egg shells. Egg samples were taken from the storage room, the eggcradle in the cage system and from the nest and floor in the floor system. To get a generalimpression of the hygiene at the farms, swab tests and air tests were performed. Swab testswere performed with a sterile cotton swab at the same units as the eggs were sampled andair tests were performed by opening petri dishes where the hens were staying.

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