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15 Uppsatser om Crushed aggreagate - Sida 1 av 1

Stenmjöl eller naturgrus i betong : En jämförande studie

 The objective of this thesis is to examine the difference in workability in fresh concrete, when crushed fine aggregate replaces natural gravel. The shape of the fine aggregate,  packing and flow of six crushed material and three natural materials will be determined by easy studies, the results will be compared with a slump cone test..

Övergång till helkrossballast : En studie för Strängbetongfabrikerna i Veddige och Herrljunga

This exam report has been developed in association with Strangbetong AB, Sweden.The natural gravel that is being used as fine aggregate for concrete production today is an ending natural recourse and the Swedish government has decided to strongly reduce the extraction from the year of 2020. The only reasonable replacement is aggregates from crushed rocks but this material has other properties than natural aggregates. The concrete manufacturers now have to learn how to use these new fine aggregates in a cost effective way in order to ensure the quality of their concrete production.In this project, crushed aggregates and combination of crushed and natural aggregates have been tested with existing formulas for fresh concrete. The two parameters yield stress and plastic viscosity have been measured which gives a good description of the workability of the fresh concrete. Different methods to make measurements on the dry fine aggregates, has also been tested, to find out if there is any correlations between these parameters and the parameters from the measurement on the fresh concrete..

När och varför dör smågrisarna under diperioden?

The purpose of this study was to compile when and why piglets die during the suckling peri-od. Piglet mortality is an important factor influencing the profitability of piglet production. There are many factors that play a role and interact whit each other. This study summarizes when the piglets die during the suckling period and reasons why the piglets die. The infor-mation given is crushed, illness, management/environmental, genetic influence and piglet birth weight/farrowingprocess.

Stubbtransporter och bränslekvalitet hos stubbved :

Stump wood is a hot alternative when the heating plants demands more and more forest fuel. The aim with the study has bean to calculate the costs in four different systems for transportations of stump wood, examine if there are any differences in fuel quality for the stump wood in the different systems, analyse if the fuel quality in stump wood is affected with the time it lays by the road side and how much space the stump wood demands on the road side. To calculate the costs for the different systems a system analysis was carried out, where some of the costs were collected through field studies on Holmen Skog stump experiment and other costs were collected from literature and contacts. Data for the fuel quality study was collected from Eons heat plant in Norrköping. Data for the study of how much space stump wood takes along a roadside was collected from field studies.

Stubbtransporter - en jämförelse av tre olika transportsystem

In Sweden, the demand for bio energy has increased in recent years due to the current energy and climate debate. In 2008, the energy supply of Sweden was 612 TWh, biofuels accounted for 123 TWh of these. Stumps have been highlighted as a potential fuel in recent years and the Swedish Forest Agency expects a technically and biologically feasible potential of 20.7 TWh annually between 2010 and 2019. The idea of utilize stumps is not new. During the 19th century stumps were used for tar production and during the 70?s and 80?s attempts were made to use stumps in the pulp industry.

Brandgravar : Yngre järnålder i Broe, Halla socken, på Gotland : en studie i olika metoder, med fokus på kremeringen

This essay concerns the osteological cremated skeletal remains from Broe, Halla parish, Gotland of  The Late Iron Age.The focus of this essay is to determine the position of the corpse on the pyre, whether the cremated bones were crushed after or prior to the cremation and if the individual was buried in the pyre. In addition the species, age, sex and skeletal abnormalities of the bones in question will be studied.The result of the research has yielded that the cremated bones did not need to be crushed to result in the small fragment sizes. Crushing of the bones may have happened during the cremation, this conclusion has been drawn through the comparison of a pyre experiment were bone fragmentation is evident with cremated foxes, and dogs in the cremation graves from Broe. The construction of the pyre and the position of the corpse could not be determined through colouring and fragmentation of the bones.The human's were commonly buried in the pyre, and in some cases it is possible that the "grave" in fact is the remainder of a pyre. The species found are dog, horse, cow, sheep/goat and bear.

Inverkan av flisig krossballast på betong

Concrete is one of the world?s most common construction materials and is composed of 70-80 % stone material. Today crushed stone is used as aggregate in concrete in order to replace natural aggregates due to strong environmental reasons. Stone crushing yields flaky material and in this thesis studies are made on the flaky particle shape and how it influence properties of concrete such as workability, rheology and strength. The concrete recipes used in this thesis have fixed values, the only variable is the flakiness of the crushed stone.

Maternal behaviour in pigs and its relation to piglet performance and survival

Piglet survival is of importance because it affects the farmer?s economy and the welfare of the pigs. There are several factors affecting piglet survival and they are often linked to each other. This paper will focus on how the behaviour of the sow can affect the growth and survival of the piglets and also possible causations of differences in maternal behaviour. Sows in intensive production systems have different possibilities to express their maternal behaviour than free ranging sows.

Bibaggar i Halländska grustäkter

This report is a result of a first survey of Halland?s gravel pits as an assignment from the County Administrative Board of Halland. The focus has been on Apalus bimaculatus, since the Swedish Environmental Protection Agency are creating a restoration program as it is red listed as Near Threatened. The purpose was also to get an overview of the pits since the County Administrative Board wants to continue this project. Apalus bimaculatus is easy to overlook since it is a short-lived beetle and it lives early in the spring.

Grovkrossning av stubbar : en produktivitetsstudie

The Swedish parliament has decided that Sweden should increase its usage of renewable fuel sources to a level of 50% of the total energy consumption in Sweden by the year 2020. One way to reach that goal may be to increase the usage of stumps as a bio-fuel. In Sweden stump harvesting is possible on about 5-10% of the total harvested area and thus contribute with 1,3 - 2,6 TWh per year. An increase stump harvest doesn't come without its drawbacks for the environment. When harvesting stumps a tracked excavator is used to pry the stumps from the ground and then cut the stumps into smaller pieces.

Buntning av grot med lastbilsmonterad utrustning :

During the transportation of logging residues (LR) the material´s low density is a problem that results in low use of pay-load capacity. Comminution or compression of LR are possible methods to increase pay-loads. In the present thesis studied a bundling machine which was mounted on a truck chassis, and the subsequent transport and crushing. The truck bundler created bundles that were larger and longer than other bundling equipment on the market. The objectives were to determine the total time consumption and its allocation over work element and machinery, to measure dry matter (DM) content of green and brown LR-bundles.

?It?s time to break the rules?, Kvinnligt författarskap i ett postrevolutionärt Egypten

AbstractTitle:?It?s time to break the rules?, Female writing in a post revolutionary Egypt Year: 2013Author: Teresa Egfors GergesKeywords: the modern Arabic short story, Egyptian female writers, the Egyptian revolution, romanticism, realism, modernism, Modern Standard Arabic, Cairo Arabic.The purpose of this essay is to analyze four stories, written by Egyptian women and published after the Egyptian revolution, namely; A?wal mimm? yanbagh? and Qi??a shatwiyya by Hanan Elbadawi and Bint r?gil and Sam?ra ?-?ar?b?sh? by Shaimaa Elmaria. The stories of the essay are analyzed by the questions:? What are the themes? ? What kind of language and style is it? ? What are the messages?The essay is based on a comparing analyze, the stories are especially analyzed by Sabry Hafez? theories about the modern Arabic short story. Interviews with the two writers have been made.

Vad påverkar en travhästs hållbarhet? : en undersökning med fokus på djurskyddsaspekten gällande träningsrutiner och behandlingsmetoder för träningsrelaterade skador bland svenska travtränare

The harness racing industry has roots hundreds of years back in time and breeders through time have changed the horses to a mix of potential, harmony and speed. Breeding has changed the conditions and created a horse that perform better and better. A risk with high-performance horses is that injuries related to training and racing may occur more often. In training and racing situations, lameness is the most common injury. There are many factors affecting the occurrence of injuries and lameness of the trotter horses, such as how the horse is trained and raced, the surface condition of the racetrack, banking and angle of the curves of the racetrack and how fast injuries are discovered and treated.

SARS

SARS [Severe Acute Respiratory Syndrome] penetrated China in spring of 2003, created havoc in the social society, exposed weaknesses within the political system and pushed the nation towards a crisis of confidence. At the same time the crisis revitalised the Party's position, brought people from different social stratum together and had a beneficial impact on the populace's knowledge on health related issues.What makes the SARS crisis in China interesting for further and deeper investigation is the method it chose to respond to its national crisis. They plan of response was indeed a retrogression back to "older" times, using methods and propaganda very much like those used during Mao Zedong and later Deng Xiaoping. The first step of response was denial and cover up of the real situation, which quickly turned to unprecedented transparency, as the magnitude of SARS became known. The Party and the government were quick to proclaim themselves as the bearer of the key knowledge and information on how to best fight the disease, this in sharp contrast to the political trend of more co-operation between the private and public sector and political transparency.

Effekt av naturligt förekommande beta-glukan hos vuxna med hyperkolesterolemi ? en systematisk översiktsartikel med fokus på livsmedel i Svensk handel.

Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionAbstractTitle: The effect of naturally existent beta-glucan in adults with hypercholesterolemia. - a systematic review with focus on the Swedish food market.Author: Ida Edman Hellberg, Frida HanssonSupervisor: Mette AxelsenExaminer: Anna WinkvistProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 01, 2014Background EFSA states in 2010 that there are good evidence that three grams of beta-glucan/day from oat as a part of a balanced diet, has a positive effect on total cholesterol and LDL.Objective Evaluate if there is evidence for primary treatment of lifestyle related hypercholesterolemia with products naturally containing beta-glucan.Search strategyIn February 2014 the databases PubMed and Scopus were used for article research. The search terms used were; cholesterol level, beta-glucan, hypercholesterolemia, oat and barley.Selection criteria Articles, written in Swedish and English, on RCT-studies conducted on otherwise healthy adults with hypercholesterolemia (serum cholesterol >5,0 mmol/L) were included. The intervention product must naturally contain beta-glucan, and an equally product should be retailed in Swedish grocery stores. The control group needed to be supplied with a placebo product and the participants could not be on any lipid-lowering medication.