Sökresultat:
653 Uppsatser om Chemical composition - Sida 6 av 44
Modellering av mekatroniksystem för spjällstyrning
To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.
Optimering av satellitbredband offshore
To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.
Recept- och rapporthantering inom blandningsteknik
To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.
Multilateral och unilateral säkerhetspolitisk praktik och strategi för hantering av Syrienkonflikten
This security study attempts to explain the dynamics of international conflict management of an intrastate conflict, through a combination of three theoretical frameworks. The conflict in Syria is shown to be managed mainly through strategies using coercive diplomacy, and some main contributions within the research field relating to strategies of coercion are used for guidance, to important factors which could affect coercive international conflict management, as well as to additional theories which could enhance the study?s explanatory power through a combined theoretical framework. The two added theoretical frameworks are Power Balancing and a Multidimensional concept of Power. With the aid of analytical tools derived from this combined framework the conflict management is analysed within both a multilateral and unilateral setting, offering some explanation as to why international conflict management (practiced by UNSC multilaterally and USA unilaterally) has shown so little progress in regard to the conflict, as well as why one significant, though limited, result could be achieved regarding the destruction of the Syrian regime?s chemical weapons arsenal..
Studier av utseendet på askan i sodapannor med hjälp av bildanalys
To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.
Effekter av landskapets sammansättning på humlearters förekomst
The species in the genus bumblebees (Bombus) are important pollinators. In the world there are 250 bumblebee species and there are 34 species in Norway. The purpose of this study is 1) to assess changes in the species composition of bumblebees in twenty different places in Norway that have been inventoried first one time between 1939-1960 and the second time in 2012, and 2) to relate species richness and distributions to current landscape composition with the aid of orthophotos. In this study, I have used regression analyzes on the different bumblebee species that were present or absent at the inventory, using the premises of the following variables: low or high altitude, latitude, longitude and seven different types of land use (farmland, building/plots, open land/pasture, forest, wetland and open or snow-covered ground above the tree line) to see if there was any relationship between each species and the different variables.
I have not analyzed what the landscape looked like at the first inventories and therefore we cannot say whether it has changed and if that is why species number has decreased. This would be interesting to study further and to see if there is any relationship between landscape changes and bumblebee?s species decline.
Förekomst av ultra-fina partiklar och partiklar ?10µm vid diatermianvändning med mobilt rökutsug : Jämförelse av partikelnivåer centralt och perifert på operationssal
Flertalet studier har påvisat ett samband mellan koncentrationen av partiklar ? 10µm i luftföroreningar och cardiovaskulär- och pulmonell morbiditet och mortalitet. Vid resektion, koagulering/bränning med diatermipenna under operationer alstras rök. Denna rök innehåller bland annat mutagena och carcinogena partiklar i inhalerbar storlek (partiklar ? 10µm).Ett första syfte med denna studie var att kvantifiera den mängd ultra-fina partiklar (UFP) och partiklar ? 10µm som operationspersonal exponeras för i operationsrummet, vid användande av diatermi med mobilt rökutsug.
Hur mycket "mjölk" ska det vara i mjölken, och hur styr vi det?
In most countries, the dairy industry focuses on the volume of milk produced instead of its composition. This results in a high content of water and a lower proportion of fat and protein. A high proportion of water is not desirable when processing the milk into various dairy products like cheese, cream and milk powder. High water content also increases the costs for transport and storage, and also an unnecessary, albeit marginal, strains on the world?s water reservoir.
En jämförande studie av fluiddynamiken för olika fluidiseringsmedium i en kallmodell av en 100 kW-anläggning för kemcyklisk förbränning
To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.
Hur ofta hälsar du på din granne? : En kvantitativ studie av integration som förklaringskraft beträffande befolkningssammansättning och radikala högerpopulistiska åsikter
A logical cause of migration is of course immigrants which is a topic always creating discussions. When arriving in a new country a process of integration with the goal to adapt to the environment is started. This study will explore the need for integration and seeks to examine the connection between population composition and radical right opinions.To fulfill the aim, a multivariate regression analysis is done on aggregated level in Sweden with statistics concerning the year of 2010. The relation between ethnic composition and voters support for the Swedish radical right party Sverigedemokraterna is studied as well as integration as an explanatory intermediate factor operationalized through unemployment, financial assistance and trust.The results of the study indicate a positive connection between immigrants from EU/EFTA and the voter support for Sverigedemokraterna. A negative relation is identified between trust and the voter support for Sverigedemokraterna.
Extraterrestrisk och terrestrisk kromrik spinell i fanerozoiska kondenserade sediment
This study aims to assess the normal inflow of extraterrestrial chromite to Earth. The results from the investigationare compared to earlier studies of middle Ordovician Orthoceratite Limestone in which 1 - 3 extraterrestrial chromitegrains ( >63 ?Êm ) per kilogram limestone were found. These values have been interpreted as evidence of a twoorders of magnitude increase in the flux of extraterrestrial matter to Earth during a part of middle Ordovician.From an early Paleocene marine sedimentary sequence with known sedimentation rate in Zumaia, northernSpain, 90,5 kilogram of condensed limestone, dated to about 63 Ma, was sampled. The limestone was dissolved inhydrochloric- and hydrofluoric acid and the residue was sieved and searched for opaque minerals under the binocularmicroscope.
Vitpunktsförskjutningens påverkan på ICC-profiler vid användande av optiska vitmedel
The connection between fluorescence and color management still is a relatively unexplored area. Thefollowing composition analyses the theory that when printing on fluorescent ink jet paper using ICCprofilesa more yellow print will appear. In theory the ICC-profile compensate for blue light that fluorescefrom the paper with the complementary color, yellow. The human eye apprehands this fluorescentlight as white.When categorizing a number of ink jet qualities some tests to indicate change of color in the final printwere made. Five qualities were chosen for further analyses, each with different white point.
Energieffektivisering i ett reningsverk för skogsindustriellt avloppsvatten genom förfällning av extraktivämnen
Pulp- and papermills expend vast amounts of water in order to produce pulp, paper and cardboard. Hence, they alsocreate vast amounts of waste water which has to be cleaned before it can be released into the receiving body of water. Insuch a wastewater treatment plant, tremendous amounts of energy are expended by the aeration in the biologicalcleaning process. This aeration is necessary to supply the microorganisms that shall decompose organic material withoxygen, which they need for their metabolism. The transfer of oxygen from the gas phase to the liquid phase isprimarily inhibited by surface-active substances in the waste water like resin acids or fatty acids.
Projektering av en etanolfermenteringsanläggning i pilotskala med Biostilteknologi
AbstractThis degree thesis was made in cooperation with Chematur Engineering in Karlskoga.Many of the environmental issues of today are a result of the motor traffic. Consumption of fossil fuels harms our environmental through formation of carbon dioxide and other greenhouse gases. To get under control with our environmental issues it?s important to find substitutes for oil that are both cheap and environmentally friendly. Ethanol has a long history as a motor fuel and is both enviromentally friendly has a high efficiency.According to the EU commissions directives for motor fuels, 5, 75 % of all the fuels in Sweden should be renewable in 2010.
Förutsättningar för hantering av kemikalierisker i förskolor : En fallstudie av Haninge kommun
Goods that children come in contact with on a daily basis for example toys, electronics, textiles, household items, have attracted an increased attention in recent years because of a common occurrence of residues of potentially hazardous chemical substances. Some municipalities in Stockholm have developed plans for managing chemical risks and work systematically to phase out products containing hazardous substances. This thesis aims to contribute to an improved knowledge base for any future work with non-toxic nursery schools in Haninge. The study's focus is on the challenges encountered by conditions and problems of preschool personnel to manage chemical risks in early childhood environments. Primary data was collected through a qualitative approach based on semi-structured interviews with both the preschool staff and practitioners working in the central organization of the municipality.