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Shape modification of embedded nanoparticles can be achieved by means of swift heavy ion irradiation. During irradiation, the particles elongate and align with the direction of the ion beam, presumably due to nanometer-scale phase transitions induced by individual ion impacts. However, the details of this transformation are not fully understood. The shape of metal nanoparticles embedded in dielectric matrices defines the non-linear optical properties of the composite material. Therefore, understanding the transformation process better is beneficial for producing materials with the desired optical properties. We study the elongation mechanism of gold nanoparticles using atomistic simulations. Here we focus on long-timescale processes and adhesion between the nanoparticle and the matrix. Without the necessity of ad-hoc assumptions used earlier, our simulations show that, due to adhesion with the oxide, the nanoparticles can grow in aspect ratio while in the molten state even after silicon dioxide solidifies. Moreover, they demonstrate the active role of the matrix: Only explicit simulations of ion impacts around the embedded nanoparticle provide the mechanism for continuous elongation up to experimental values of aspect ratio. Experimental transmission electron microscopy micrographs of nanoparticles after high-fluence irradiation support the simulations. The elongated nanoparticles in experiments and their interface structures with silica, as characterized by the micrographs, are consistent with the simulations. These findings bring ion beam technology forward as a precise tool for shaping embedded nanostructures for various optical applications.

The shape of metal nanoparticles embedded in dielectric matrices influences the optical properties of the composite material. Swift heavy ion irradiation can induce a controllable shape transformation in gold and other metals embedded in amorphous silicon dioxide, where the particles elongate along the direction of the ion beam. The details of this transformation are not fully understood, but it is presumably related to nanometer-scale phase transitions induced by individual ion impacts. The phenomenon has been reproduced using atomistic simulations, although the time scale limitations and the lack of accurate interatomic models within the metal-silica interface lead unavoidably to severe simplifications. We improve the realism in the simulations with an accurate model for surface adhesion between gold and silica and by simulating the processes in the matrix between impacts. The simulations with correct adhesion show that the nanoparticles can grow in aspect ratio in the molten state even after silicon dioxide solidifies. Moreover, we demonstrate the active role of the matrix: without explicitly modeling processes in the matrix between impacts, the elongation is limited and does not reach significant aspect ratios seen in experiments. These results significantly improve the theoretical understanding of processes developing in embedded nanoparticles under swift heavy ion irradiation. The knowledge brings forward the ion beam technology as a precise tool for shaping of embedded nanostructures for various optical applications., 22 pages, 7 figures, supplementary material

Tiedonhallinta ja -käyttö on noussut suureksi haasteeksi jatkuvasti globalisoituvassa organisaatioiden toimintaympäristöissä. Tähän haasteeseen on vastattu erilaisilla tietojärjestelmillä. Tässä diplomityössä keskitytään Enterprise Resource Planning (ERP) järjestelmän käyttöönoton analysointiin. Diplomityön tavoitteena oli käyttöönottaa Netsuite ERP-järjestelmä Logistic TKT Systems Oy:ssä kahdessa tuotantoympäristössä, toteuttaa projektimalli muiden tuotantoyksiköiden käyttöönotoille ja listata ERP-järjestelmän seuraavat kehitysaskeleet. Käyttöönoton tukena toteutettiin kirjallisuuskatsaus ERP-järjestelmien ominaisuuksiin ja käyttöönottoihin liittyen. Työn tutkimusvaihe suoritettiin nykytila-analyysin, vaatimusmäärittelyn ja pilotoinnin avulla. Nykytila-analyysi ja vaatimusmäärittely toteutettiin asiantuntijatyöpajassa ja pilotointi suoritettiin projektiryhmän toimesta. Kirjallisuuskatsaus antoi näkökulman ERP-projektin moniulotteisuudelle. ERP-järjestelmän käyttöönotto projektin tärkeimpiä onnistumistekijöitä ovat organisaation prosessien muokkaaminen järjestelmään sopivaksi, järjestelmän asettamien rajoitteiden huomioiminen ja muutosjohtamisen laatu. Nykytila-analyysin ja vaatimusmäärittelyn avulla varmistettiin projektin toteutuskelpoisuus ja määriteltiin projektin lähtötila sekä tavoitteet. Käyttöönoton suurimpana tavoitteena oli tiedon lisääminen yrityksessä ja tiedon automaattinen hyödyntäminen. Tämän tiedon perusteella luotiin raportteja, joita voidaan hyödyntää tuotannon- ja varastonhallinnassa ja jälkilaskelmissa. Käyttöönoton ja kirjallisuuskatsauksen perusteella projektimalli tulevia käyttöönottoja varten saatiin kartoitettua ja automaattinen raportointi lisääntyi huomattavasti yrityksessä. Suurimpana haasteena ja epäonnistumistekijänä projektissa koettiin muutosjohtamisen epäonnistuminen. Tämän seurauksena loppukäyttäjien sitouttaminen järjestelmän käyttöön ei onnistunut toivotulla tavalla. Data management and usage has become one of the most significant challenge in globalized operation environment. To respond this challenge, organizations has implemented different data management systems. In this thesis, Enterprise resource planning (ERP) system is implemented, and implementation analysis is completed. The target for thesis work is to implement Netsuite ERP system to two production environments at Logistic TKT Systems Oy and develop implementation model for future implementations in other production environments. At the same time will be planned next step after thesis work. To support ERP implementation, literature review was collected regarding ERP system properties and implementations. Thesis’ research phase executed by state of art, requirements analysis and piloting in two production environments. State of art and requirement analysis was executed by expert workshops and piloting was done by project team. Literature review gave a view for multidimensionality of ERP project. ERP system implementation’s greatest success factors are modifying organization’s processes a line with system’s processes, recognizing limitations in the system and the quality of management of change. Project plan, current state and target state was defined with state of art and requirement analysis. Implementation’s greatest targets were increasing data collection and automated data utilization. With that information reports were created to help with production planning, warehouse management and calculating historical costs. Based on literature review and ERP implementation a project model was created for future ERP implementations and automated reporting increased significantly. The biggest challenge and failure were management of change. Because of that, there was challenges to commitment end users to this change.

Creating a competitive advantage is often contextualized as the finding the Holy Grail of strategy. This study examines how Nordic sports businesses incorporate sustainability and how it can be used as a strategy to create a competitive advantage. The climate change debate, and increased consumer environmental consciousness has compelled companies to endeavor for a sustainable development. The sport industry has in general lacking behind in the green transition. However, they are now progressively trying to reconstruct their businesses model to a more sustainable approach. Consequently, more companies are today trying to market their brands to be perceived as sustainable. Although, the challenge is to how position a brand as sustainable without being accused for greenwashing. The thesis structure is based on three segments. Corporate sustainability, sustainability marketing and corporate transformation. The study was based on a qualitative research method, based from six case study interviews with companies from Sweden and Finland. The main research findings was that sustainability has become an increasingly important issue for Nordic sports businesses. The driving force behind the sustainable development is three different stakeholder. Customers, policy makers and employees at the own organization. The Agenda 2030 can be seen as a powerful and tangible set of framework, used to better implement sustainability. Another finding is that sustainability is mostly communicated on product level rather than on corporate level because of the fear of greenwashing accusation. Finally, creating a competitive advantage through corporate sustainability is the main objectives. In order to accomplish that desired outcome, the strategy have to been based on sound businesses practices which depends on how the company is using, and absorbing both internal and external resources and capabilities.

When a swift heavy ion (SHI) penetrates amorphous SiO2, a core/shell (C/S) ion track is formed, which consists of a lower-density core and a higher-density shell. According to the conventional inelastic thermal spike (iTS) model represented by a pair of coupled heat equations, the C/S tracks are believed to form via "vaporization" and melting of the SiO2 induced by SHI (V-M model). However, the model does not describe what the vaporization in confined ion-track geometry with a condensed matter density is. Here we reexamine this hypothesis. While the total and core radii of the C/S tracks determined by small angle x-ray scattering are in good agreement with the vaporization and melting radii calculated from the conventional iTS model under high electronic stopping power (S-e) irradiations (>10 keV/nm), the deviations between them are evident at low-S, irradiation (3-5 keV/nm). Even though the iTS calculations exclude the vaporization of SiO2 at the low S-e, both the formation of the C/S tracks and the ion shaping of nanoparticles (NPs) are experimentally confirmed, indicating the inconsistency with the V-M model. Molecular dynamics (MD) simulations based on the two-temperature model, which is an atomic-level modeling extension of the conventional iTS, clarified that the "vaporlike" phase exists at S-e similar to 5 keV/nm or higher as a nonequilibrium phase where atoms have higher kinetic energies than the vaporization energy, but are confined at a nearly condensed matter density. Simultaneously, the simulations indicate that the vaporization is not induced under 50-MeV Si irradiation (S-e similar to 3 keV/nm), but the C/S tracks and the ion shaping of nanoparticles are nevertheless induced. Even though the final density variations in the C/S tracks are very small at the low stopping power values (both in the simulations and experiments), the MD simulations show that the ion shaping can be explained by flow of liquid metal from the NP into the transient low-density phase of the track core during the first similar to 10 ps after the ion impact. The ion shaping correlates with the recovery process of the silica matrix after emitting a pressure wave. Thus, the vaporization is not a prerequisite for the C/S tracks and the ion shaping.

Ions in the keV energy range are regularly used in the semiconductor industry for device fabrication. Irradiation with ions of higher energies can also induce favorable structural changes in the irradiated samples. Among these, irradiation effects of the so-called swift heavy ions (SHIs, heavy ions with specific energies in the 1 MeV / amu range) in electrically insulating materials are particularly interesting. Despite the wide range of existing applications (filters, printed circuit boards and geological dating) and application potential (fuel cells, cell mimicking membranes) of SHI irradiation, the mechanisms by which SHIs interact with insulators are still under debate. Modelling of SHIs is a very challenging task as, contrary to ions with lower energies, they mostly interact with electrons, inducing lots of electronic excitations. Incorporating the latter with atomistic dynamics is especially difficult in insulators, and the methods have not yet been fully established. SHIs can induce a cylindrical region of structural transformation known as an ion track. In crystalline silicon dioxide, a track consists of an amorphized region that is typically several microns long and has a radius of less than ten nanometers. Furthermore, it was recently found out that SHI irradiation can be used to induce a shape transformation in metal nanoclusters (NCs) that are embedded in amorphous silicon dioxide. Spherical NCs (radius 1-50 nm) elongate along the ion beam direction and are shaped into nanorods or prolate spheroids. The phenomenon can be exploited to produce large arrays of equally aligned nanoclusters within a solid substrate, which is difficult to achieve otherwise. In this thesis, ion track formation and the elongation of gold nanoclusters in silicon dioxide are studied using so called two-temperature molecular dynamics simulations. The structure of the tracks is studied and a mechanism is proposed for the nanoparticle elongation effect. The work presented here is a step towards the understanding of SHI related effects in a broader range of insulating materials for the SHI based applications. Tapa, jolla raskas ioni vuorovaikuttaa aineen kanssa riippuu suuresti sen nopeudesta. Tavallisissa ionisäteilyn sovelluskohteissa (esimerkiksi puolijohdekomponenttien valmistaminen) ionin nopeus on suuruudeltaan sellainen (ts. ionin kineettinen energia on suuruusluokaltaan kiloelektronivoltteja), että ionin ja aineen atomien välisissä törmäyksissä liike-energia siirtyy suoraan aineen atomiytimille. Tämänkaltaisten ionien käyttäytyminen aineessa osataan ennustaa hyvin. Vaikeammin ennustettavissa ovat nopeudeltaan suurempien ionien vaikutukset, kun ionin kineettinen energia on kymmeniä tai satoja megaelektronivoltteja. Nämä ionit (ns. ripeät raskas-ionit) jarruuntuvat aineessa pääasiassa törmäyksissä aineen elektronien kanssa. Myös ripeillä raskas-ioneilla on sovelluskohteita. Niitä käytetään esimerkiksi suodattimien valmistamiseen. Lisäksi geologisten näytteiden iänmääritys voidaan suorittaa perustuen ripeiden raskas-ionien vaikutukseen. Ei kuitenkaan ole olemassa yleisesti hyväksyttyä teoriaa, joka kuvaisi säteilyvaikutuksen syntymistä ionin nopeuden ollessa suuri. Työssä tutkitaan kahta ripeiden raskas-ionien säteilyvaikutusta piidioksidissa tietokonesimulaatioiden avulla. Ionit voivat indusoida aineeseen sylinterinmuotoisen rakennemuutoksen, jota kutsutaan ionin jäljeksi. Kiteisessä piidioksidissa jälki muodostuu amorfisesta alueesta, joka on tyypillisesti useita mikrometrejä pitkä ja jonka säde on pienempi kuin 10 nanometriä. Näiden rakennetta ja syntyä tutkitaan. Lisäksi tiedetään, että ripeät raskas-ionit voivat aikaansaada rakennemuutoksen amorfisen piidioksidin sisällä oleviin metallisiin nanohiukkasiin. Pallonmuotoiset nanohiukkaset (säde 1-50 nm) pitenevät ionisäteen suunnassa ja muokkautuvat nanoputkiksi tai sferoideiksi. Ilmiötä hyödyntämällä voidaan kasvattaa suuria määriä samaan suuntaan osoittavia nanopartikkeleja kiinteän aineen sisällä. Rakennetta on vaikea valmistaa muilla keinoilla. Simulaatiotuloksiin perustuen työssä ehdotetaan mekanismia, jolla nanopartikkelit pitenevät. Työn tulokset lisäävät ripeiden raskas-ionien vaikutusten ymmärrystä, mikä on tärkeää sovellusten kannalta.

Familiar materials show interesting properties when their size is reduced to the nanoscale. At the same time, controlling and tuning something so small becomes a challenge of its own. Metal nanoparticles, for instance, show interesting optical properties such as narrow peaks in their absorption spectra. The location of this peak depends on not only the material of the nanoparticle, but also on its shape. Controlling the shape of a nanoparticle can be done in different ways. One of them is irradiation using swift heavy ions. The latter are able to penetrate deep into the material, allowing for modification of nanoparticles embedded in insulators to protect them from environment. Swift heavy ion irradiation is known to affect the aspect ratio of embedded metal nanoparticles. Because the process happens in a picosecond timescale, the only plausible way to study the process with sufficient resolution is to use computer simulations. In this work we use both the multiscale atomistic simulations which include atomic and electronic dynamics, as well as a continuum model for larger structures to understand the driving mechanisms for swift heavy ion modification of Au nanoparticles embedded in silica. First we look into the shape modification in the subtrack regime. A cylindrical damage region – an underdense core-overdense shell track – created in the wake of the passing ion was believed to be the prerequisite for nanoparticle shape modification. The explanation is based on material flow of a molten nanoparticle into the underdense ion track. In the subtrack region, however, these tracks are not experimentally measurable, but nanoparticles still elongate. This observation was in apparent contradiction to the previous explanation. We show that the shape change is still possible, because of the transient tracks that form on a picosecond time scale. This confirms that the suggested earlier mechanism holds, while no permanent tracks are required. In our study, we have also included shape modification of nanorods. Such elongated nanoparticles have not been yet as extensively studied as spherical ones. Experimentally, we observed an apparent rotation of the nanorods that were initially positioned perpendicular to the ion beam. After irradiation, however, all nanorods were found to be aligned with the ion beam direction. Using atomistic simulations of the multiple subsequent impacts, we explained the "rotation" by re-orientation of the nanorod in a series of incremental shape modifications that cumulatively made the nanorod "rotate". Furthermore, we improved our atomistic simulation models by introducing a new interatomic potential for the interface between the nanoparticle and the surrounding insulator. Earlier atomistic simulations had the weakness that while they could show shape change after one simulated ion impact, these changes did not accumulate with multiple impacts without additional tweaks between the impacts. The latter was necessary to account for processes not accessible within the existing models in order for the elongation process to continue. With the use of the new potential, and by including side impacts around the nanoparticle as well as longer cooling between the ion impacts, we were able to accumulate the shape changes without the use of any poorly motivated ad hoc models. The multiscale nature of atomistic simulations of swift heavy ion impacts includes the solution of two coupled partial differential equations, a so-called two-temperature model that describes the heat dynamics in both atomic and electronic subsystems. Although these equations are routinely solved for Au-SiO2 systems, the complex nature of possible effects in the interface between the metal and insulator had not been this far taken into account. These models suggested that a nanoparticle melts fully or partially via the deposition of energy to silica, which is a prerequisite for their shape transformation. The excited electrons from the nanoparticle, in these models, reach the surface without a barrier, depositing their energy to the atoms of the insulator material close to the interface and subsequently melting the nanoparticle from the outside. We found that taking into account that an insulator around the gold nanoparticle effectively traps the electrons of gold in a potential well, and reduces the energy that can leak from the nanoparticle when its electrons are excited. We also saw that including interface scattering in the heat simulations, increases the heating in the surface of the nanoparticle. With these two effects also taken into account, we studied the effects of thermal insulation caused by a material interface between gold and silica. The atomic heat conduction between the nanoparticle and its surrounding became negligibly small. The only source of heating was the energy trapped inside the nanoparticle because of the barrier. Our study showed that when this energy was sufficiently high in medium-sized < 80 nm diameter nanoparticles, large regions of the nanoparticle still melted, consistent with experimental results. Overall, in this work, we have improved the realism of both the two-temperature model and the atomistic simulations that are used together to simulate swift heavy ion impacts on materials. With these improvements, we can better understand the shape modification of metal nanoparticles under swift heavy ion irradiation. This new understanding can be used to better control the processthat can be used in the production of future nanoscale optical devices. Monet arkiset ja tutut materiaalit muuttuvat mielenkiintoisiksi kun niiden kokoluokkaa skaalataan nanometrimittaluokkaan. Esimerkiksi kultaiset nanopartikkelit reagoivat valoon eri tavalla kuin paljaalla silmällä erottuvat kultaiset kappaleet. Nämä pienestä koosta johtuvat ominaisuudet voivat osoittautua hyödyllisiksi tulevaisuuden elektronisissa sovelluksissa. Nanomittakaavassa olevien kappaleiden muodon tarkka säätäminen ei ole helppoa, mutta muoto vaikuttaa kuitenkin nanopartikkelien ominaisuuksiin. Eräs tapa muokata eristeisiin upotettuja metallisia nanopartikkeleita on niiden säteilyttäminen ripeillä raskas-ioneilla (Swift heavy ion). Tämä työ käsittelee tällaisen nanopartikkelien säteilytyksen teoreettista mallintamista tietokonesimulaatioiden avulla. Suhteessa aiempiin aiheesta tehtyihin tutkimuksiin, uusina tuloksina tässä työssä on nanosauvojen kääntymisen selittäminen, sekä sellainen säteilytys, joka ei vaikuta jättävän jälkiä nanopartikkeleita ympäröivään eristemateriaaliin, mutta kuitenkin muuttaa sisällä olevien nanopartikkelien muotoa. Lisäksi tässä työssä on tutkittu nanopartikkelien ja niitä ympäröivät eristemateriaalin rajapinnassa tapahtuvia fysikaalisia ilmiöitä. Vaikka tämä työ on keskittynyt aiheen teoreettiseen tutkimukseen, voi sen tuloksista olla hyötyä tulevaisuudessa, erityisesti jos nanopartikkelipohjaiset elektroniset sovellutukset yleistyvät.