Painelaitteen hitsauksen kehittäminen

Työ tehtiin Steris Finn Aqualle, joka oli ottanut tuotantoon uuden autoklaavimallin kevään 2007 aikana. Työn tavoitteena oli kehittää painelaitteen hitsausta vertailemalla kevytmekanisointi, mekanisointi ja robotisointiratkaisuja ja hankkia riittävät tiedot mahdollisen investointipaatoksen tueksi. Tarkastellut kevytmekanisointilaitteet koostuivat kuljetinkiskosta, kuljettimesta ja mahdollisesta railonseurantalaitteesta. Tarkasteltu mekanisointijärjestelmä oli asiakaskohtaisesti räätälöitävä kokonaisuus. Tarkasteltuun hitsausrobottijärjestelmään kuului kappaleenkäsittelylaite sekä etäohjelmointiohjelmisto. Työn teoriaosassa käsiteltiin painelaitelainsäädännön vaikutuksia tuotantoon, ruostumattoman ja haponkestävän teräksen ominaisuuksia hitsauksen kannalta, tuotannossa käytettäviä hitsausprosesseja, hitsauksen mekanisointia ja automatisointia sekä railonseurantaa. Työn käytännön osuudessa käytiin läpi painelaitevalmistuksen nykytila. Painelaitevalmistus jaettiin eri työvaiheisiin ja työvaiheet analysoitiin, millä varmistettiin, että kehitysresurssit suunnataan oikeisiin kohteisiin. Kehitysehdotuksena esitettiin joko railonseurannalla varustetun kevytmekanisointilaitteiston tai etäohjelmoitavan hitsausrobottijärjestelmän hankintaa. Kevytmekanisoinnilla on mahdollista saavuttaa samat edut kuin kalliimmillakin mekanisointilaitteilla ja kevytmekanisoinnin etuna on käyttöönoton helppous ja laitteiston edullisuus. Hitsausrobotin hankintaan liittyy epävarmuustekijöitä, joiden tarkempi selvittäminen on tarpeen, ennen hitsausrobotin hankintapaatosta. Suuremmilla tuotantomäärillä hitsausrobottisolu olisi ollut selkeästi parempi ratkaisu.

Tekijännimet Mikael Agricolan teosten kielessä. Henkilötarkoitteisten johdosten merkitykset, funktiot ja rakenteet

My research deals with agent nouns in the language of the works of Mikael Agricola (ca. 1510–1557). The main tasks addressed in my thesis have been to describe individual agent noun types, to provide a comprehensive picture of the category of agent nouns and to clarify the relations between different types of agent nouns. My research material consists of all the agent nouns referring to persons in the language of Agricola’s works, together with their context. The language studied is for the most part translated language. Agent nouns play an important role both in the vocabulary of natural language and in broader sentence structures, since in a text it is constantly necessary to refer to actors re-ferring to persons in the text. As a concept and a phenomenon, the agent noun is widely known in languages. It is a word formed with a certain derivational affixes, which typical-ly refers to a person. In my research the agent noun category includes both deverbal and denominal derivatives referring to persons, e.g. kirjoittaa > kirjoittaja (to write > writer), asua > asuva (to inhabit > inhabitant), imeä > imeväinen (to suck > suckling), juopua > juopunut (to drink > drunkard), pelätä > pelkuri (to fear > one who fears ‘a coward’), apu > apulainen (help/to help > helper); lammas > lampuri (sheep > shepherd). Besides original Finnish expressions, agent noun derivatives taken as such from foreign languages form a word group of central importance for the research (e.g. nikkari, porvari, ryöväri, based on the German/Swedish for carpenter, burgher, robber). Especially important for the formation of agent nouns in Finnish are the models offered by foreign languages. The starting point for my work is predominantly semantic, as both the criteria for collecting the material and the categorisation underlying the analysis of the material are based on semantic criteria. When examining derivatives, aspects relating to structure are also inevitably of central importance, as form and meaning are closely associated with each other in this type of vocabulary. The alliance of structure and meaning can be described in an illustrative manner with the help of structural schemata. The examination of agent nouns comprises on the one hand analysis of syntactic elements and on the other, study of cultural words in their most typical form. The latter aspect offers a research object in which language and the extralinguistic world, referents, their designations and cultural-historical reality are in concrete terms one and the same. Thus both the agent noun types that follow the word formation principles of the Finn-ish language and those of foreign origin borrowed as a whole into Finnish illustrate very well how an expression of a certain origin and formed according to a certain structural model is inseparably bound up with the background of its referent and in general with semantic factors. This becomes evident both on the level of the connection between cer-tain linguistic features and text genre and in relation to cultural words referring to per-sons. For example, the model for the designations of God based on agent nouns goes back thousands of years and is still closely linked in 16th century literature with certain text genres. This brings out the link between the linguistic feature and the genre in a very con-crete manner. A good example of the connection between language and the extralinguistic world is provided by the cultural vocabulary referring to persons. Originally Finnish agent noun derivatives are associated with an agrarian society, while the vocabulary relat-ing to mediaeval urbanisation, the Hansa trade and specialisation by trade or profession is borrowed and originates in its entirety from vocabulary that was originally German.

Kielioppi suomen kielen opiskelijoille

Kirjallisuusarvostelu

Kurzrezensionen

Kirjallisuusarvostelu

Production of Mg(OH)2 from Mg-silicate rock for CO2 mineral sequestration

Sequestration of carbon dioxide in mineral rocks, also known as CO2 Capture and Mineralization (CCM), is considered to have a huge potential in stabilizing anthropogenic CO2 emissions. One of the CCM routes is the ex situ indirect gas/sold carbonation of reactive materials, such as Mg(OH)2, produced from abundantly available Mg-silicate rocks. The gas/solid carbonation method is intensively researched at Åbo Akademi University (ÅAU ), Finland because it is energetically attractive and utilizes the exothermic chemistry of Mg(OH)2 carbonation. In this thesis, a method for producing Mg(OH)2 from Mg-silicate rocks for CCM was investigated, and the process efficiency, energy and environmental impact assessed. The Mg(OH)2 process studied here was first proposed in 2008 in a Master’s Thesis by the author. At that time the process was applied to only one Mg-silicate rock (Finnish serpentinite from the Hitura nickel mine site of Finn Nickel) and the optimum process conversions, energy and environmental performance were not known. Producing Mg(OH)2 from Mg-silicate rocks involves a two-staged process of Mg extraction and Mg(OH)2 precipitation. The first stage extracts Mg and other cations by reacting pulverized serpentinite or olivine rocks with ammonium sulfate (AS) salt at 400 - 550 oC (preferably < 450 oC). In the second stage, ammonia solution reacts with the cations (extracted from the first stage after they are leached in water) to form mainly FeOOH, high purity Mg(OH)2 and aqueous (dissolved) AS. The Mg(OH)2 process described here is closed loop in nature; gaseous ammonia and water vapour are produced from the extraction stage, recovered and used as reagent for the precipitation stage. The AS reagent is thereafter recovered after the precipitation stage. The Mg extraction stage, being the conversion-determining and the most energy-intensive step of the entire CCM process chain, received a prominent attention in this study. The extraction behavior and reactivity of different rocks types (serpentinite and olivine rocks) from different locations worldwide (Australia, Finland, Lithuania, Norway and Portugal) was tested. Also, parametric evaluation was carried out to determine the optimal reaction temperature, time and chemical reagent (AS). Effects of reactor types and configuration, mixing and scale-up possibilities were also studied. The Mg(OH)2 produced can be used to convert CO2 to thermodynamically stable and environmentally benign magnesium carbonate. Therefore, the process energy and life cycle environmental performance of the ÅAU CCM technique that first produces Mg(OH)2 and the carbonates in a pressurized fluidized bed (FB) were assessed. The life cycle energy and environmental assessment approach applied in this thesis is motivated by the fact that the CCM technology should in itself offer a solution to what is both an energy and environmental problem. Results obtained in this study show that different Mg-silicate rocks react differently; olivine rocks being far less reactive than serpentinite rocks. In summary, the reactivity of Mg-silicate rocks is a function of both the chemical and physical properties of rocks. Reaction temperature and time remain important parameters to consider in process design and operation. Heat transfer properties of the reactor determine the temperature at which maximum Mg extraction is obtained. Also, an increase in reaction temperature leads to an increase in the extent of extraction, reaching a maximum yield at different temperatures depending on the reaction time. Process energy requirement for producing Mg(OH)2 from a hypothetical case of an iron-free serpentine rock is 3.62 GJ/t-CO2. This value can increase by 16 - 68% depending on the type of iron compound (FeO, Fe2O3 or Fe3O4) in the mineral. This suggests that the benefit from the potential use of FeOOH as an iron ore feedstock in iron and steelmaking should be determined by considering the energy, cost and emissions associated with the FeOOH by-product. AS recovery through crystallization is the second most energy intensive unit operation after the extraction reaction. However, the choice of mechanical vapor recompression (MVR) over the “simple evaporation” crystallization method has a potential energy savings of 15.2 GJ/t-CO2 (84 % savings). Integrating the Mg(OH)2 production method and the gas/solid carbonation process could provide up to an 25% energy offset to the CCM process energy requirements. Life cycle inventory assessment (LCIA) results show that for every ton of CO2 mineralized, the ÅAU CCM process avoids 430 - 480 kg CO2. The Mg(OH)2 process studied in this thesis has many promising features. Even at the current high energy and environmental burden, producing Mg(OH)2 from Mg-silicates can play a significant role in advancing CCM processes. However, dedicated future research and development (R&D) have potential to significantly improve the Mg(OH)2 process performance.

Adapting to a team of host culture domination: Experiences of Finnish and British expatriates

International teams are permanent features of the global market, and multinational companies cannot ignore them. This thesis discusses an individual’s adaptation to a team of host culture domination by looking at the experiences of Finnish and British expatriates. The research question is: How does a foreigner adapt to a Finnish-British team where all the other members are from the local culture? The theoretical framework of this thesis consists of theories on multicultural teamwork and Finnish and British cultures. Based on theories, the impact of diversity on teamwork and whether it improves or deteriorates a team’s performance is unclear but the idea of multicultural teams is not just to live with cultural differences but to use and benefit of them. The main differences between Finnish and British cultures are in management styles and level of hierarchy. Still, these two cultures seem to be very similar. This is a qualitative study and expert interviews were used as a method for data collection. The results of the empirical research showed that Finns and Brits have differences in decision-making, level of hierarchy and communication. None of the informants saw the challenges that they have faced to result from being the only representative of a foreign culture – they only perceived them resulting from the characteristics of the host culture. In addition, all the informants had to change their habits and behaviour in the host culture in order to fit into the new culture and to become a part of the team. However, all the informants saw advantages in cross-cultural teams. Based on this thesis, team members from the host culture do not value cultural differences and they seem to be an issue only for the team member from the minority culture. It seems that a Finn or a Brit adapts to a Finnish-British team where the host culture dominates by changing their own behaviour in order to become a part of the team – even though people often see their own culture’s methods and habits as the right ones. Finnish and British cultures seem to be similar in fundamental issues like views and attitudes, which could mean that it is fairly easy for a Finn to get used to working in a British team and vice versa. Even though there are many challenges in cross-cultural and bi-cultural teams, there are even more advantages.