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11707 Uppsatser om Material properties - Sida 1 av 781

Teknik i förskolan : En studie om hur 4 - 5 åringars uppfattningar om material och dess egenskaper kan utvecklas genom en pedagogisk aktivitet

The purpose of this work is to investigate how 4-5 year olds perceptions of materials and Material properties can be developed through an educational activity. The study is based on two interviews with eight children in that age category. The interviews were conducted before and after an activity where the children were first introduced to the subject by the tale of The three little pigs (Harris, 2009) and then given the opportunity to explore various materials related to the book. The kids got to experiment and explore how water affected materials and to compare different materials properties. The children were also attracted to build and create the material that was offered during the activity.

Tuftade ljudabsorbenter ? väggpaneler för rumsliga och akustiska egenskaper

It is a well-known fact that textiles and carpets have benign sound-absorbing properties. It is desirable to have quantified values of these properties ? especially for architects and interior designers. They often need to be able to giveaccount for the acoustic properties of their designs at a relatively early stage and sometimes have strict acoustic classifications imposed upon them by their contractor. A product with documented acoustic properties would aid when prescribing interior elements.The purpose of this thesis is to develop a wall-mounted panel in hand-tufted material ? aesthetically pleasing and versatile but also having documented and quantified acoustic properties.

Hållfasthetsegenskaper i gjutjärn : tensile properties of cast iron

In the last few years people have become more and more aware of how humanity is affecting the climate. In the direction of reducing the greenhouse gases is to design engines with higher tensile properties and reduced weight, in order to achieve lower fuel consumption and cleaner fuel incineration in today's truck engines.In order to achieve these requirements it?s necessary to increase the combustion pressure in the engine. This requires higher tensile properties and high thermal conductivity of the engine material. The department of Component Technology at the University of Jönköping in collaboration with Volvo Powertrain AB, Scania CV AB and DAROS Piston Rings AB has been commissioned to develop this material and to find knowledge of Material properties used in truck engines and piston rings used for marine applications.The purpose with this work is to analyze the tensile properties of a series of cast iron, cast under different metallurgical conditions.Four different series of cast irons have been analyzed from four points of view, carbon concentration, nodularity, amount inoculation and cooling rate.After the tensile test all specimen data was analyzed in a mathematic calculation program called Matlab 2006a.

Vad förmedlar en förskolas barnböcker ur ett genusperspektiv? : En kvantitativ studie av 136 barnböcker

The purpose of this study is to investigate how male and female is produced in the literary children?s literature that is found in a Municipal preschool. My issues are the following:Which sex dominates as a main character in the preschools literary books?What type of properties is attributed to the characters?What type of clothes is portrayed on the books characters?I performed a quantitative study of 136 children?s books. I used Maria Nikolajevas perceptions of stereotypical male and female properties to analyze my empirical data.

Alternativa förpackningsmaterial och konstruktioner för »Hackman tools«-serien

Choosing a new plastic material for a container includes several different steps. In this case,the Finnish company Hackman needed a new type of packaging material for theircutlery- and kitchentool series »Hackman tools«. The project was carried out in cooperationwith the design agency Ytterborn & Fuentes, which has Hackman as a client.Several different demands were put on the material in order to fulfill as many of the clientswishes as possible. The most urgent problem with the existing container was the difficultysfor the customer to clearly see the contents in the container. Because of this problemthe customer tried to open the container in the shop.

Double integrating spheres: A method for assessment of optical properties of biological tissues

The determination of the optical properties of biological tissue is an important issue in laser medicine. The optical properties define the tissue´s absorption and scattering behaviour, and can be expressed by quantities such as the albedo, the optical thickness and the anisotropy coefficient. During this project, a measurement system for the determination of the optical properties was built up. The system consists of a double integrating sphere set-up to perform the necessary reflection and transmission measurements, and a computer algorithm to calculate the optical properties from the measured data. This algorithm is called Inverse Adding Doubling method, and is based on a one-dimensional transport model.

Hur tillförlitlig är värderingen av förvaltningsfastigheter?: En studie av tillämpningen av IAS 40

This thesis studies the way valuation of investment properties is conducted in accordance with IAS 40 and how reliable these valuations are. This has been conducted by studying ten Swedish real estate companies listed on the NASDAQ OMX, during the period 2005-2008. The study shows that all companies use valuation models to determine the fair value of investment properties. Two different types of models have been identified. Companies that use the cash flow model show inconsistencies in time horizon, and how they determine the horizon value.

Trä som fasadmaterial ? behandling och beständighet

Since prehistoric time man has used wood to build their environment. The material?s availabilitycombined with its good mechanical properties has often made it the material of choice. Like allmaterials exposed to natures degradative processes the properties of wood decreases over time.Rot, UV radiation and attacks by insects and pests damage wood if not protected. Since we wantwhat we build to consist, optimizing our building materials durability is of great interest.Techniques and methods for increasing the endurance of wood have been developed in severaldifferent places and for a long time.

En studie av metodbyte vid sintring av hårdmetaller till mikrovågsintring samt dess ekonomiska fördelar : Självständigt arbete i teknisk fysik med materialvetenskap & Självständigt arbete i kemiteknik

The aim with this study was to investigate the effects a change of manufacturing process would have on the mechanical properties of drill bits made of a WC/Co composite used for stone cutting. The method used today is sintering, where the material is heated in a conventional sintering oven. The other method was microwave sintering, where the material is heated by radiation in the microwave region. Also an investigation of the manufacturing cost were made.The main difference between the two heating methods is that the conventional way is a rather slow process and the microwave method is very fast. The material is also heated homogeniously in the method with mirowaves, aposed to the case with the conventional sintering where the material is heated from the outside in.This makes the material harder and more wear resistent.

Det industriella byggandets betydelse för skapandet av de estetiska egenskaperna i bostadens arkitektur - En fallstudie på företaget JM AB

The study aims to investigate the impact of industrialised homebuilding in the creation of the aestheticproperties of the dwelling architecture.The concepts of industrialised homebuilding and the aesthetic properties of the dwelling architecture aredefined by previously developed models. In these models, industrialised homebuilding is described byeight characteristic areas. The aesthetic properties of the dwelling architecture are described by sevenaesthetic qualities.The study was conducted as a qualitative study, and in-depth interviews were conducted. The companyJM AB is the analysed unit that the author of this report has chosen to study. JM employees and by JMhiredarchitects were interviewed.The report concludes that characteristic area planning and control of processes are considered to havepositive impact on the aesthetic qualities if the process is designed in such a way that the creations ofthese are admitted.

Prefabricerade väggelement av hampabetong

Lime Hempcrete consists of lime, water and hemp and creates an insulating, sound-absorbing, lightweight and environmentally friendly material that can be used in wall, roof and floor structures (Bevan & Woolley 2008). This construction method is not yet developed in Sweden as there has been a ban on the cultivation of the hemp plant. This ban on the cultivation of hemp was removed in 2003, when the material got a boost. You can use it in many different ways and not just in the construction industry (Ahlsten, 2010).In this study we have investigated the possibility to produce prefabricated wall elements of LHC. We have also studied its mechanical properties and dehydration time.

Karaktärisering av hårdmetallpulvrets råvaror och dess påverkan på pulvrets flödesegenskaper

This thesis has been done at the powder department (GH) at AB Sandvik Coromant in Gimo. With a rheometer measurements has been made on raw materials and powder blends. The focus of this report has been to find correlations between raw material powders and press data, comparisons have also been made between raw materials and powder blends.The rheometer can show information of how a powder act in flow conditions, together with air and with pressure. Analyses has been done comparing the rheometer data with press parameters (for example: rejected orders, weight variations and the compaction pressure) with the goal to find correlations between the powders flow properties and the powders compaction in production.The measurements and analyses have been showing that the powder flow properties depends on the powders composition and that properties like flow rate, aeration and permeability varies between powder blends and batches of the same powder sort. It seems to exist a correlation between the pressure force and the flow rate of a raw material.

Medical Care : En jämförelse mellan kursinnehållet och dess utförande i Sverige och i Danmark som leder till ett internationellt certifikat i Medical Care

This thesis has been done at the powder department (GH) at AB Sandvik Coromant in Gimo. With a rheometer measurements has been made on raw materials and powder blends. The focus of this report has been to find correlations between raw material powders and press data, comparisons have also been made between raw materials and powder blends.The rheometer can show information of how a powder act in flow conditions, together with air and with pressure. Analyses has been done comparing the rheometer data with press parameters (for example: rejected orders, weight variations and the compaction pressure) with the goal to find correlations between the powders flow properties and the powders compaction in production.The measurements and analyses have been showing that the powder flow properties depends on the powders composition and that properties like flow rate, aeration and permeability varies between powder blends and batches of the same powder sort. It seems to exist a correlation between the pressure force and the flow rate of a raw material.

Termomekanisk utmattning av Sanicro 25 : Materialmodellering med finita elementmetoden

The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal ? and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well.

Utvärdering av kalkstens egenskaper med laboratorie- och fältmetoder.

A pavement construction designed to cope with the different type of traffic loads; it is exposed to and at the same time it can resist the effect of the climate. A road structure consists of sub- and superstructure which is divided by a boundary known as terrace. During the construction of unbound layers (base course and sub-base course) in the superstructure, it is always ensured that the material meet the requirements for bearing capacity and the degree of compaction. These parameters are controlled by various laboratory tests and control methods. To obtain increased knowledge of the material and improve the quality of the compaction in the field, it is necessary to perform laboratory tests in order to determine Material properties.A base course material 0/ 32 mm limestone from Gotland (Hejdeby) was investigated in this study.

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