64 resultados para cyclic oxidation – Ti3SiC2-base material – scale spallation – adherence
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Selective papers of the workshop on "Development of models and forest soil surveys for monitoring of soil carbon", Koli, Finland, April 5-9 2006.
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The calcified tissues, comprising bone and cartilage, are metabolically active tissues that bind and release calcium, bicarbonate and other substances according to systemic needs. Understanding the regulation of cellular metabolism in bone and cartilage is an important issue, since a link between the metabolism and diseases of these tissues is clear. An essential element in the function of bone-resorbing osteoclasts, namely regulation of bicarbonate transport, has not yet been thoroughly studied. Another example of an important but at the same time fairly unexplored subject of interest in this field is cartilage degeneration, an important determinant for development of osteoarthritis. The link between this and oxidative metabolism has rarely been studied. In this study, we have investigated the significance of bicarbonate transport in osteoclasts. We found that osteoclasts possess several potential proteins for bicarbonate transport, including carbonic anhydrase IV and XIV, and an electroneutral bicarbonate co-transporter NBCn1. We have also shown that inhibiting the function of these proteins has a significant impact on bone resorption and osteoclast morphology. Furthermore, we have explored oxidative metabolism in chondrocytes and found that carbonic anhydrase III (CA III), a protein linked to the prevention of protein oxidation in muscle cells, is also present in mouse chondrocytes, where its expression correlates with the presence of reactive oxygen species. Thus, our study provides novel information on the regulation of cellular metabolism in calcified tissues.
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The properties of the paper surface play a crucial role in ensuring suitable quality and runnability in various converting and finishing operations, such as printing. Plasma surface modification makes it possible to modify the surface chemistry of paper without altering the bulk material properties. This also makes it possible to investigate the role of the surface chemistry alone on printability without influencing the porous structure of the pigment-coated paper. Since the porous structure of a pigment coating controls both ink setting and optical properties, surface chemical changes created by a plasma modification have a potential to decouple these two effects and to permit a better optimization of them both. The aim of this work was to understand the effects of plasma surface modification on paper properties, and how it influences printability in the sheet-fed offset process. The objective was to broaden the fundamental understanding of the role of surface chemistry on offset printing. The effects of changing the hydrophilicity/ hydrophobicity and the surface chemical composition by plasma activation and plasma coatings on the properties of coated paper and on ink-paper interactions as well as on sheet-fed offset print quality were investigated. In addition, the durability of the plasma surface modification was studied. Nowadays, a typical sheet-fed offset press also contains units for surface finishing, for example UVvarnishing. The role of the surface chemistry on the UV-varnish absorption into highly permeable and porous pigment-coated paper was also investigated. With plasma activation it was possible to increase the surface energy and hydrophilicity of paper. Both polar and dispersion interactions were found to increase, although the change was greater in the polar interactions due to induced oxygen molecular groups. The results indicated that plasma activation takes place particularly in high molecular weight components such as the dispersion chemicals used to stabilize the pigment and latex particles. Surface composition, such as pigment and binder type, was found to influence the response to the plasma activation. The general trend was that pilot-scale treatment modified the surface chemistry without altering the physical coating structure, whereas excessive laboratory-scale treatment increased the surface roughness and reduced the surface strength, which led to micro-picking in printing. It was shown that pilot-scale plasma activation in combination with appropriate ink oils makes it possible to adjust the ink-setting rate. The ink-setting rate decreased with linseed-oil-based inks, probably due to increased acid-base interactions between the polar groups in the oil and the plasma-treated paper surface. With mineral-oil-based inks, the ink setting accelerated due to plasma activation. Hydrophobic plasma coatings were able to reduce or even prevent the absorption of dampening water into pigmentcoated paper, even when the dampening water was applied under the influence of nip pressure. A uniform hydrophobic plasma coating with sufficient chemical affinity with ink gave an improved print quality in terms of higher print density and lower print mottle. It was also shown that a fluorocarbon plasma coating reduced the free wetting of the UV-varnish into the highly permeable and porous pigment coating. However, when the UV-varnish was applied under the influence of nip pressure, which leads to forced wetting, the role of the surface chemical composition seems to be much less. A decay in surface energy and wettability occurred during the first weeks of storage after plasma activation, after which it leveled off. However, the oxygen/carbon elemental ratio did not decrease as a function of time, indicating that ageing could be caused by a re-orientation of polar groups or by a contamination of the surface. The plasma coatings appeared to be more stable when the hydrophobicity was higher, probably due to fewer interactions with oxygen and water vapor in the air.
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Pro gradu -tutkielmassa tutkitaan julkisissa hankinnoissa kyttn otettavien uusien shkisten menettelyjen, shkisen huutokaupan ja dynaamisen hankintajrjestelmn, yritysvaikutuksia. Ydintutkimustehtvn on tutkia, millaisia taloudellisia vaikutuksia shkisill menettelyill tulee olemaan yrityksiin niiden tarjotessa palveluita tai tavaroita julkiselle sektorille ja mitk ovat shkisten menettelyjen kytn motiivit. Tutkielman teoriaosa on pohja empiiriselle tutkimukselle, jossa aineistona on kytetty suppeaa kyselytutkimusta, haastatteluja ja lisksi materiaalia on tuotettu analysoimalla hallinnollisten kustannusten mr shkisiss hankintamenettelyiss. Yritysvaikutusten arvioinnissa tarkasteltiin shkisten hankintamenettelyjen kytn motiiveja. Motiiveiksi tunnistettiin tehokkuuden tavoittelu, kustannussstt, ajankytn ja henkilresurssien kytn tehostaminen sek avoimuus. Tutkimuksessa onnistuttiin todentamaan edell mainittuja tekijit taloudellisilla malleilla. Mrlliset ja laadulliset tutkimustulokset osoittavat kokonaisuudessaan tuloksellisella tavalla shkisten hankintamenettelyjen kytn motiiveita ja vaikutuksia yrityksiin. Shkisill hankintamenettelyill voidaan perustellusti tehostaa hankintaprosessia ja saavuttaa kustannussstj. Monia yleisi yritysten julkisiin hankintoihin psyn estein pitmi seikkoja voitaisiin vhent tai poistaa kyttmll shkisi hankintoja. Shkist huutokauppaa ja dynaamista hankintajrjestelm koskevan lainsdnnn luodessa puitteet menettelyiden kytlle, tulee menettelyjen kyttnoton motiivien ja kannustimien riittvyytt seurata. Hallinnollisten kustannusten vheneminen ja muiden esteiden pieneneminen ei vlttmtt synnyt pysyv kannustinvaikutusta, vaan hankintaprosessia tulee pyrki shkistmn kokonaisvaltaisesti mys muissa hankintalain mukaisissa hankintamenettelyiss ja kilpailuttamisen ulkopuolisissa hankinnan osa-alueissa kuten laskuttaminen, maksatus ja tilaus.
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Tm diplomity ksittelee Neste Oilin Porvoon jalostamon HF-alkylointiyksikn alasajon ja huoltopysytyksen rajapintaa. Tyss tarkastellaan erilaisia vaihtoehtoja alasajon aikaisen neutralointi- ja puhdistusprosessin kehittmiseen huomioiden materiaalitekninen nkkulma. Tyn alkuosassa esitelln alkyloinnin perusperiaate, huoltopysytysprosessi sek eri neutralointi- ja puhdistusprosessit, joista tarkemmin nykyisin jalostamolla kytettv EnvTech:n prosessi. Tyss on mys kerrottu alkyloinnin erityisvaatimukset materiaaleille, joista tarkemmin on esitelty perusmateriaaleina kytettvt hiiliters A106 sek Monel 400. Niden perusmateriaalien kohdalla on mys esitelty kirjallisuuden pohjalta niiden kyttytyminen fluorivety-ympristss. Tyn loppuosassa on esitelty eri vaihtoehtoja, jotta kyttvarmuutta voitaisiin kehitt yhdess mahdollisesti kasvavien tuotantomrien kanssa. Putkistojen kohdalla tyss on ksitelty kehityskohteeksi valittua erst pkolonni-osaan kuuluvaa linjastoa. Eri vaihtoehtoja on vertailtu teknistaloudelliselta nkkulma ja putkiston kohdalla on tyss pdytty geometrian muuttamiseen sek koon kasvattamiseen. Tyss on mys esitetty kuumatypetysvaiheen uudelleen aikataulutusta alasajovaiheen nopeuttamiseksi sek jatkotutkimusehdotuksia putkiston passivoimisesta, rautafluoridikalvon paikalleen jttmiseksi ja huoltopysytyssyklin kehittmiseksi.
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Intensive and critical care nursing is a speciality in its own right and with its own nature within the nursing profession. This speciality poses its own demands for nursing competencies. Intensive and critical care nursing is focused on severely ill patients and their significant others. The patients are comprehensively cared for, constantly monitored and their vital functions are sustained artificially. The main goal is to win time to cure the cause of the patients situation or illness. The purpose of this empirical study was i) to describe and define competence and competence requirements in intensive and critical care nursing, ii) to develop a basic measurement scale for competence assessment in intensive and critical care nursing for graduating nursing students, and iii) to describe and evaluate graduating nursing students basic competence in intensive and critical care nursing by seeking the reference basis of self-evaluated basic competence in intensive and critical care nursing from ICU nurses. However, the main focus of this study was on the outcomes of nursing education in this nursing speciality. The study was carried out in different phases: basic exploration of competence (phase 1 and 2), instrumentation of competence (phase 3) and evaluation of competence (phase 4). Phase 1 (n=130) evaluated graduating nursing students basic biological and physiological knowledge and skills for working in intensive and critical care with Basic Knowledge Assessment Tool version 5 (BKAT-5, Toth 2012). Phase 2 focused on defining competence in intensive and critical care nursing with the help of literature review (n=45 empirical studies) as well as competence requirements in intensive and critical care nursing with the help of experts (n=45 experts) in a Delphi study. In phase 3 the scale Intensive and Critical Care Nursing Competence Scale (ICCN-CS) was developed and tested twice (pilot test 1: n=18 students and n=12 nurses; pilot test 2: n=56 students and n=54 nurses). Finally, in phase 4, graduating nursing students competence was evaluated with ICCN-CS and BKAT version 7 (Toth 2012). In order to develop a valid assessment scale of competence for graduating nursing students and to evaluate and establish the competence of graduating nursing students, empirical data were retrieved at the same time from both graduating nursing students (n=139) and ICU nurses (n=431). Competence can be divided into clinical and general professional competence. It can be defined as a specific knowledge base, skill base, attitude and value base and experience base of nursing and the personal base of an intensive and critical care nurse. Personal base was excluded in this self-evaluation based scale. The ICCN-CS-1 consists of 144 items (6 sum variables). Finally, it became evident that the experience base of competence is not a suitable sum variable in holistic intensive and critical care competence scale for graduating nursing students because of their minor experience in this special nursing area. ICCN-CS-1 is a reliable and tolerably valid scale for use among graduating nursing students and ICU nurses Among students, basic competence of intensive and critical care nursing was self-rated as good by 69%, as excellent by 25% and as moderate by 6%. However, graduating nursing students basic biological and physiological knowledge and skills for working in intensive and critical care were poor. The students rated their clinical and professional competence as good, and their knowledge base and skill base as moderate. They gave slightly higher ratings for their knowledge base than skill base. Differences in basic competence emerged between graduating nursing students and ICU nurses. The students self-ratings of both their basic competence and clinical and professional competence were significantly lower than the nurses ratings. The students self-ratings of their knowledge and skill base were also statistically significantly lower than nurses ratings. However, both groups reported the same attitude and value base, which was excellent. The strongest factor explaining students conception of their competence was their experience of autonomy in nursing. Conclusions: Competence in intensive and critical care nursing is a multidimensional concept. Basic competence in intensive and critical care nursing can be measured with self-evaluation based scale but alongside should be used an objective evaluation method. Graduating nursing students basic competence in intensive and critical care nursing is good but their knowledge and skill base are moderate. Especially the biological and physiological knowledge base is poor. Therefore in future in intensive and critical care nursing education should be focused on both strengthening students biological and physiological knowledge base and on strengthening their overall skill base. Practical implications are presented for nursing education, practice and administration. In future, research should focus on education methods and contents, mentoring of clinical practice and orientation programmes as well as further development of the scale.
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Ilmavoimien johtamisjrjestelm on osa Ilmavoimien jrjestelmkokonaisuutta, jonka kaksi muuta osaa ovat taistelujrjestelm ja tukeutumisjrjestelm. Ilmavoimien materiaalista suorituskyky rakennetaan tmn jrjestelmajattelun pohjalta. tss tutkimuksessa Ilmavoimien johtamisjrjestelm tutkitaan kolmen kokonaisuuden, ilmavalvontajrjestelmn, ilmatilannekuvan muodostamisjrjestelmn ja tulenkytn johtamisjrjestelmn, nkkulmasta. Ilmavoimien johtamisjrjestelmn laajuuden vuoksi tutkimusaluetta on jouduttu rajaamaan. Tutkimus perustuu evoluutioparadigmaan, jonka mukaisesti kaikki olevainen on evolutionaarista. Mikn tss ajassa oleva ilmi ei ole historiaton. Jokaisella ilmill on nykyisyytens lisksi historia ja tulevaisuus. Evoluutioparadigman avulla laajennetaan Ilmavoimien johtamisjrjestelmn nykyisyyden ymmrtmist kuvaamalla ja analysoimalla sen evoluutiota. Tutkimusaineistoa analysoidaan kytten hyvksi polkuriippuvuutta evolutionaarisena mallina. tt mallia on kytetty uusinstitutionaalisessa ja evolutionaarisessa taloustieteess ja taloushistoriassa tutkittaessa yritysten, toimialojen tai tuotteiden pysyvyytt markkinoilla sek erilaisten innovaatioiden vaikuttavuutta menestymiseen eri markkinatilanteissa. Tutkimusasetelman lhtkohtana on Ilmavoimien johtamisjrjestelmevoluution kuvaaminen kolmen tekijn tasapainoasetelman suhteen, joita ovat instituutiot, ilmasotateoria ja kansainvlinen ilmavoimien johtamisjrjestelmn kehitys. tutkimuksen tavoitteena on lyt institutionaalinen logiikka Ilmavoimien johtamisjrjestelmn evoluutiolle sek sen eri kehitysprosesseihin liittyv mahdollinen polkuriippuvuuden logiikka. Tutkittavina instituutioina ovat kansallinen poliittinen ptksenteko, joka ilmentyy erilaisina komiteamietintj, raportteina ja selontekoina. Sotilaallista instituutiota edustavat eri operatiiviset ohjeet, ohjesnnt ja doktriinit, jotka ovat ohjanneet johtamisjrjestelmkehityst. Ilmasotateorian vaikuttavuuden analyysi varten tutkimuskohteiksi on valittu seitsemn merkittv ilmasotateoreetikkoa. Kenraalimajuri Giulio douhet, ilmamarsalkka Hugh Trenchard ja kenraalimajuri William Mitchell edustavat ilmasotateorian varhaista kautta. Kansallista ilmasotateorian kehityst edustavat eversti Richard Lorentz ja kenraalimajuri Gustaf Erik Magnusson. Yhdysvaltalaiset everstit John Boyd ja John Warden III ovat uuden ajan ilmasotateoreetikkoja. Niden henkiliden tuottamien teorioiden avulla voidaan piirt kuva muutoksesta, jota ilmasodankynnin teoreetti- sessa ajattelussa on tapahtunut. Ilmavoimien johtamisjrjestelmn evoluutiolle haetaan vertailua kehityksest, jota on tapahtunut Yhdysvalloissa, Isossa-Britanniassa ja Saksassa. Ilmavoimat on saanut vaikutteita muistakin maista, mutta niden maiden kehityksen avulla voidaan selitt Suomessa tapahtunutta kehityst. Tutkimuksessa osoitetaan, ett kansainvlisell johtamisjrjestelmevoluutiolla on ollut merkittv vaikutus suomalaiseen kehitykseen. Tm tutkimus laajentaa prosessuaalista tutkimusteoriaa ja polkuriippuvuusmallin kytt sotatieteelliseen tutkimuskenttn. tutkimus yhdist toisiinsa aivan uudella tavalla sotilasorganisaation institutionaalisia tekijit pitkss evoluutioketjussa. Tutkimus luo pohjaa prosessuaaliseen, havaintoihin perustuvaan evoluutioajatteluun, jossa eri tekijiden selitysmalleja ja kausaalisuutta eri periodien aikana voidaan kuvata. Tutkimuksen tuloksena ilmavoimien johtamisjrjestelmevoluutiossa paljastui merkittvi piirteit. Teknologia on ollut voimakas katalysaattori ilmapuolustuksen evoluutiossa. Uusien teknologisten innovaatioiden ilmestyminen taistelukentlle on muuttanut oleellisesti taistelun kuvaa. Sodankynnin revoluutiosta huolimatta sodankynnin tai operaatiotaidon ja taktiikan perusperiaatteissa ei ole tapahtunut perustavanlaatuista muutosta. Ilmavoimien johtamisjrjestelmn kehitys on voimakkaasti linkittynyt ulkomaiseen johtamisjrjestelmkehitykseen, jossa teknologiaimplementaatiot perustuvat usean eri ilmin paljastumiseen ja hyvksikyttn. Sotilas- ja siviili-instituutiot ovat merkittvsti vaikuttaneet Ilmavoimien johtamisjrjestelmn kansalliseen kehitykseen. Ne ovat antaneet poliittisen ohjauksen, taloudellisten resurssien ja strategis-operatiivisten kskyjen ja suunnitelmien avulla perusteet, joiden pohjalta johtamisjrjestelm on kehitetty. Tutkimus osoittaa, ett Suomen taloudellisten resurssien rajallisuus on ollut merkittvin institutionaalinen rajoite Ilmavoimien johtamisjrjestelm kehitettess. Useat poliittiset ohjausasiakirjat ovat korostaneet, ettei Suomella pienen kansakuntana ole taloudellisia resursseja seurata kansainvlist sotilasteknologiakehityst. Lisksi ulko- ja turvallisuuspoliittinen liikkumavapaus on vaikuttanut kehittmismahdollisuuksiin. Ilmasotateorian evoluutio on luonut johtamisjrjestelmn kehitykselle vlttmttmn konseptuaalisen viitekehyksen, jotta ilmasota on voitu vied kytnnn tasolle. Teoria, doktriini ja instituutiot toimivat vuorovaikutuksessa, jossa ne interaktiivisesti vaikuttavat toinen toisiinsa. Tutkimus paljasti kuusi merkittv sokkia, jotka saivat aikaan radikaaleja muutoksia johtamisjrjestelmn evoluutiopolulla. tutkimuksen perusteella vaikuttavimmat muutoksia aiheuttavat sokit olivat radikaalit turvallisuuspoliittiset muutokset kuten sota ja voimakkaat kansantalouden muutokset kuten lama. Sokkeja aiheuttaneet kuusi ajankohtaa olivat: 1. Puolustusvoimien rakentamisen aloittaminen vapaussodan jlkeen 1918 2. Maailmanlaajuinen lama 1929–1933 ja eurooppalainen rauhanaate 1928–1933 3. Talvi- ja jatkosota 1939–1944 4. Uusi alku Pariisin rauhansopimuksen 1947 ja YYA-sopimuksen 1948 varjossa 5. Kylmn sodan pttyminen ja Suomen lama 1990–1993 6. Maailmanlaajuinen lama 2008- Tutkimuksen perusteella voidaan todeta, ett Suomen ilmavoimien johtamisjrjestelmn kehittminen on perustunut rationaalisiin ptksiin, jotka ovat saaneet vaikutteita ulkomaisesta ilmasotateorian ja -doktriinien kehityksest sek kansainvlisest johtamisjrjestelmkehityksest. Johtamisjrjestelmn evoluutioon on vaikuttanut globaali konvergenssi, johon on tehty kansallisen tason ratkaisuja jrjestelmien adaptaation ja implementaation yhteydess.
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It is known already from 1970s that laser beam is suitable for processing paper materials. In this thesis, term paper materials mean all wood-fibre based materials, like dried pulp, copy paper, newspaper, cardboard, corrugated board, tissue paper etc. Accordingly, laser processing in this thesis means all laser treatments resulting material removal, like cutting, partial cutting, marking, creasing, perforation etc. that can be used to process paper materials. Laser technology provides many advantages for processing of paper materials: non-contact method, freedom of processing geometry, reliable technology for non-stop production etc. Especially packaging industry is very promising area for laser processing applications. However, there are only few industrial laser processing applications worldwide even in beginning of 2010s. One reason for small-scale use of lasers in paper material manufacturing is that there is a shortage of published research and scientific articles. Another problem, restraining the use of laser for processing of paper materials, is colouration of paper material i.e. the yellowish and/or greyish colour of cut edge appearing during cutting or after cutting. These are the main reasons for selecting the topic of this thesis to concern characterization of interaction of laser beam and paper materials. This study was carried out in Laboratory of Laser Processing at Lappeenranta University of Technology (Finland). Laser equipment used in this study was TRUMPF TLF 2700 carbon dioxide laser that produces a beam with wavelength of 10.6 m with power range of 190-2500 W (laser power on work piece). Study of laser beam and paper material interaction was carried out by treating dried kraft pulp (grammage of 67 g m-2) with different laser power levels, focal plane postion settings and interaction times. Interaction between laser beam and dried kraft pulp was detected with different monitoring devices, i.e. spectrometer, pyrometer and active illumination imaging system. This way it was possible to create an input and output parameter diagram and to study the effects of input and output parameters in this thesis. When interaction phenomena are understood also process development can be carried out and even new innovations developed. Fulfilling the lack of information on interaction phenomena can assist in the way of lasers for wider use of technology in paper making and converting industry. It was concluded in this thesis that interaction of laser beam and paper material has two mechanisms that are dependent on focal plane position range. Assumed interaction mechanism B appears in range of average focal plane position of 3.4 mm and 2.4 mm and assumed interaction mechanism A in range of average focal plane position of 0.4 mm and -0.6 mm both in used experimental set up. Focal plane position 1.4 mm represents midzone of these two mechanisms. Holes during laser beam and paper material interaction are formed gradually: first small hole is formed to interaction area in the centre of laser beam cross-section and after that, as function of interaction time, hole expands, until interaction between laser beam and dried kraft pulp is ended. By the image analysis it can be seen that in beginning of laser beam and dried kraft pulp material interaction small holes off very good quality are formed. It is obvious that black colour and heat affected zone appear as function of interaction time. This reveals that there still are different interaction phases within interaction mechanisms A and B. These interaction phases appear as function of time and also as function of peak intensity of laser beam. Limit peak intensity is the value that divides interaction mechanism A and B from one-phase interaction into dual-phase interaction. So all peak intensity values under limit peak intensity belong to MAOM (interaction mechanism A one-phase mode) or to MBOM (interaction mechanism B onephase mode) and values over that belong to MADM (interaction mechanism A dual-phase mode) or to MBDM (interaction mechanism B dual-phase mode). Decomposition process of cellulose is evolution of hydrocarbons when temperature is between 380- 500C. This means that long cellulose molecule is split into smaller volatile hydrocarbons in this temperature range. As temperature increases, decomposition process of cellulose molecule changes. In range of 700-900C, cellulose molecule is mainly decomposed into H2 gas; this is why this range is called evolution of hydrogen. Interaction in this range starts (as in range of MAOM and MBOM), when a small good quality hole is formed. This is due to direct evaporation of pulp via decomposition process of evolution of hydrogen. And this can be seen can be seen in spectrometer as high intensity peak of yellow light (in range of 588-589 nm) which refers to temperature of ~1750C. Pyrometer does not detect this high intensity peak since it is not able to detect physical phase change from solid kraft pulp to gaseous compounds. As interaction time between laser beam and dried kraft pulp continues, hypothesis is that three auto ignition processes occurs. Auto ignition of substance is the lowest temperature in which it will spontaneously ignite in a normal atmosphere without an external source of ignition, such as a flame or spark. Three auto ignition processes appears in range of MADM and MBDM, namely: 1. temperature of auto ignition of hydrogen atom (H2) is 500C, 2. temperature of auto ignition of carbon monoxide molecule (CO) is 609C and 3. temperature of auto ignition of carbon atom (C) is 700C. These three auto ignition processes leads to formation of plasma plume which has strong emission of radiation in range of visible light. Formation of this plasma plume can be seen as increase of intensity in wavelength range of ~475-652 nm. Pyrometer shows maximum temperature just after this ignition. This plasma plume is assumed to scatter laser beam so that it interacts with larger area of dried kraft pulp than what is actual area of beam cross-section. This assumed scattering reduces also peak intensity. So result shows that assumably scattered light with low peak intensity is interacting with large area of hole edges and due to low peak intensity this interaction happens in low temperature. So interaction between laser beam and dried kraft pulp turns from evolution of hydrogen to evolution of hydrocarbons. This leads to black colour of hole edges.
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Mass-produced paper electronics (large area organic printed electronics on paper-based substrates, throw-away electronics) has the potential to introduce the use of flexible electronic applications in everyday life. While paper manufacturing and printing have a long history, they were not developed with electronic applications in mind. Modifications to paper substrates and printing processes are required in order to obtain working electronic devices. This should be done while maintaining the high throughput of conventional printing techniques and the low cost and recyclability of paper. An understanding of the interactions between the functional materials, the printing process and the substrate are required for successful manufacturing of advanced devices on paper. Based on the understanding, a recyclable, multilayer-coated paper-based substrate that combines adequate barrier and printability properties for printed electronics and sensor applications was developed in this work. In this multilayer structure, a thin top-coating consisting of mineral pigments is coated on top of a dispersion-coated barrier layer. The top-coating provides well-controlled sorption properties through controlled thickness and porosity, thus enabling optimizing the printability of functional materials. The penetration of ink solvents and functional materials stops at the barrier layer, which not only improves the performance of the functional material but also eliminates potential fiber swelling and de-bonding that can occur when the solvents are allowed to penetrate into the base paper. The multi-layer coated paper under consideration in the current work consists of a pre-coating and a smoothing layer on which the barrier layer is deposited. Coated fine paper may also be used directly as basepaper, ensuring a smooth base for the barrier layer. The top layer is thin and smooth consisting of mineral pigments such as kaolin, precipitated calcium carbonate, silica or blends of these. All the materials in the coating structure have been chosen in order to maintain the recyclability and sustainability of the substrate. The substrate can be coated in steps, sequentially layer by layer, which requires detailed understanding and tuning of the wetting properties and topography of the barrier layer versus the surface tension of the top-coating. A cost competitive method for industrial scale production is the curtain coating technique allowing extremely thin top-coatings to be applied simultaneously with a closed and sealed barrier layer. The understanding of the interactions between functional materials formulated and applied on paper as inks, makes it possible to create a paper-based substrate that can be used to manufacture printed electronics-based devices and sensors on paper. The multitude of functional materials and their complex interactions make it challenging to draw general conclusions in this topic area. Inevitably, the results become partially specific to the device chosen and the materials needed in its manufacturing. Based on the results, it is clear that for inks based on dissolved or small size functional materials, a barrier layer is beneficial and ensures the functionality of the printed material in a device. The required active barrier life time depends on the solvents or analytes used and their volatility. High aspect ratio mineral pigments, which create tortuous pathways and physical barriers within the barrier layer limit the penetration of solvents used in functional inks. The surface pore volume and pore size can be optimized for a given printing process and ink through a choice of pigment type and coating layer thickness. However, when manufacturing multilayer functional devices, such as transistors, which consist of several printed layers, compromises have to be made. E.g., while a thick and porous top-coating is preferable for printing of source and drain electrodes with a silver particle ink, a thinner and less absorbing surface is required to form a functional semiconducting layer. With the multilayer coating structure concept developed in this work, it was possible to make the paper substrate suitable for printed functionality. The possibility of printing functional devices, such as transistors, sensors and pixels in a roll-to-roll process on paper is demonstrated which may enable introducing paper for use in disposable onetime use or throwaway electronics and sensors, such as lab-on-strip devices for various analyses, consumer packages equipped with product quality sensors or remote tracking devices.
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In the present work, liquid-solid flow in industrial scale is modeled using the commercial software of Computational Fluid Dynamics (CFD) ANSYS Fluent 14.5. In literature, there are few studies on liquid-solid flow in industrial scale, but any information about the particular case with modified geometry cannot be found. The aim of this thesis is to describe the strengths and weaknesses of the multiphase models, when a large-scale application is studied within liquid-solid flow, including the boundary-layer characteristics. The results indicate that the selection of the most appropriate multiphase model depends on the flow regime. Thus, careful estimations of the flow regime are recommended to be done before modeling. The computational tool is developed for this purpose during this thesis. The homogeneous multiphase model is valid only for homogeneous suspension, the discrete phase model (DPM) is recommended for homogeneous and heterogeneous suspension where pipe Froude number is greater than 1.0, while the mixture and Eulerian models are able to predict also flow regimes, where pipe Froude number is smaller than 1.0 and particles tend to settle. With increasing material density ratio and decreasing pipe Froude number, the Eulerian model gives the most accurate results, because it does not include simplifications in Navier-Stokes equations like the other models. In addition, the results indicate that the potential location of erosion in the pipe depends on material density ratio. Possible sedimentation of particles can cause erosion and increase pressure drop as well. In the pipe bend, especially secondary flows, perpendicular to the main flow, affect the location of erosion.
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Diplomity tehtiin Suomen Sokeri Oy:n vesilaitokselle Vihren Kemian laboratoriossa. Prosessia tarkasteltiin saostuksen osalta ja tavoitteena oli sen kehittminen esihapetusmenetelmn tai saostuskemikaalin vaihdon avulla. Tarkastelu tehtiin orgaanisen, kiintoaineksen ja metallien poiston, desinfiointitehon sek ympristystvllisyyden osalta. Potentiaalisia esihapetusmenetelmi (kaliumpermanganaatti, vetyperoksidi, valokemiallinen, H2O2/UV, valokatalyyttinen, TiO2/UV, H2O2/ultrani sek esihapetus peretikkahapolla) tarkasteltiin eri pitoisuuksilla ja tehoilla laboratoriomittakaavassa jar-testin avulla. Saostustehoa testattiin alumiinikloridilla ja ferrisulfaatilla. Raakaveden laadun muutoksia eri vaiheissa seurattiin laboratorioanalyysein. Hapetusmenetelmien desinfiointiteho, vaikutukset syanobakteereihin ja -toksiineihin sek reaktioissa syntyvt sivutuotteet kartoitettiin teorian perusteella. Tyn tuloksien perusteella kaliumpermanganatti, vetyperoksidi erityisesti kehittyneen hapetustekniikkana sek valokatalyyttinen menetelm tehostivat vedenksittely, mutta koska TiO2/UV- tai ultranihapetukselle ei ole viel olemassa kaupallista sovellusta laitosmittakaavassa niin suositeltavat menetelmt ovat KMnO4- ja H2O2(/UV)-hapetukset jatkotutkimussuositukset huomioiden. Peretikkahappo ei tmn tutkimuksen perusteella vaikuttanut suositeltavalta hapetusmenetelmlt, mutta sen sijaan teorian perusteella potentiaaliselta desinfektioaineelta mys talousvedenpuhdistukseen. Opinnytetyt eri hapetusmenetelmien osalta talousvedelle ei ole aiemmin tehty eik peretikkahappohapetuksesta ole laajalti aiempaa tutkimustietoa. Kokeellisen osuuden tulokset antavat uutta tietoa menetelmien soveltuvuudesta vastaaville laitoksille.
Resumo:
Tmn pro gradu -tutkielman tarkoituksena oli kartoittaa pohjoiskarjalaisten kasvuyritysten menestystekijit. Tutkimuksen tarkoitus oli tehd alustava pohjaty pohjoiskarjalaisten kasvuyritysten ja niiss vaikuttavien menestystekijiden tarkempaa tutkimusta varten. Laajemmassa mittakaavassa tmn tutkimuksen toivotaan tuovan hyty pohjoiskarjalaiselle elinkeinoelmlle ja erityisesti aloittaville yrittjille. Tutkimus toteutettiin laadullisena tutkimuksena. Tutkimusaineisto kerttiin haastattelemalla neljn pohjoiskarjalaisen kasvuyrityksen edustajia soveltamalla teemahaastattelua. Kohdeyritykset mriteltiin kasvuyrityksiksi kyttmll EurostatOECD:n kasvuyrityksen kriteeri. Kohdeyrityksist haastateltiin kahdesta kolmeen ylimpn johtoon kuuluvaa avainhenkil, joista useimmat olivat mys yritysten omistajia. Haastattelujen perusteella muodostetut yritysnarratiivit toimivat jatkoanalysoinnin perustana. Tutkimuksessa todettiin, ett pohjoiskarjalaisen kasvuyrityksen merkityksellisimmt menestystekijt polveutuvat omistajan yrittjmisest asenteesta ja vasta tmn jlkeen tulevat yrittjn kasvuasenteisiin, yrityksen strategiseen sopivuuteen ja yrityksen resursseihin lukeutuvat menestystekijt. Mys kulttuuristen tekijiden epsuorasta vaikutuksesta yrityksen kasvuun saatiin tutkimuksessa viitteit.
Resumo:
The objective of this Masters Thesis was to conduct a wide scale preliminary survey regarding the package requirements of a cultured dairy package, and to compare the currently used material polystyrene to other suitable packaging materials. Polystyrene has a long history of use in dairy cups, but in recent years its price has increased significantly compared to other common packaging materials. The overall environmental effects of a package and a package material are today a part of designing a sustainable product life cycle. In addition, in certain contexts there has been discussion of the risks posed by styrene polymer for the environment and for humans. These risks are also discussed in this thesis. Polystyrene (PS) is still the most widely used material in dairy cups. In recent years, polypropylene (PP) cups have appeared in increasing numbers on market shelves. This study focuses on the differences of the suitable polymers and examines the suitability of alternative suitable polymers with regards to dairy packaging. Aside from focusing on the cup manufacturer, this thesis also examines its subject matter from the viewpoint of the dairy customer, as well as observing the concrete implications of material changes in the overall value chain. It was known in advance that material permeability would be one of the determining factors and that gas transmission testing would be a significant part of the thesis. Mechanical tests were the second part of the testing process, providing information regarding package strength and protectiveness during the packages life cycle. Production efficiency, along with uninterrupted stable production, was another important factor that was taken into consideration. These two issues are sometimes neglected in similar contexts due to their self-evident nature. In addition, materials used in production may have a surprising significance to the production and efficiency. Consistent high quality is also partly based on material selection. All of the aforementioned factors have been documented and the results have been analyzed by the development team at Coveris Rigid Finland. Coveris is now calculating the total finance effects and capacities should the material changes be implemented in practice. There are many factors in favor of switching to polypropylene at the moment. The overall production costs, as well as the environmental effects of resin production are the primary influences for said switch from the converters perspective.
