Fabrication of wet spun core-shell filaments from functionalized nanocelluloses

Tiivistelmä. The aim of this thesis was to investigate a novel wet spinning process based on interfacial complexation of functionalized nanocelluloses for the production of core-shell filaments or yarns. The work focused on wet spinning process development, and investigated how winding and drying steps could be integrated in the continuous spinning process, in which interfacial complexation and wet spinning are combined for filament fabrication of oppositely charged cellulose nanofibers (CNF). Additionally, the effect of processing parameters such as drying temperature, spinning speed, needle size, washing and stretching on mechanical properties of the filaments were investigated to optimize the process. A continuous process was developed by investigating different types of CNF core-shell combinations and by integrating separate unit operations to obtain a continuous filament fabrication. Three different types of filaments consisting of functionalized anionic-cationic or anionic-anionic CNF pairs (S-CNF/CDAC-CNF, TO-CNF/CDAC-CNF, and TO-CNF/TO-CNF) were successfully fabricated. The requirement for feasible continuous process and homogenous filament fabrication were the filament structure consisting of anionic core and cationic shell, proper air removal from CNFs, filament support and reduced friction during the processing, properly directed drying air and Teflon covered winder. In addition, drying temperature, spinning speed and needle size of the process were optimized. The structure of filaments were investigated by microscopy and mechanical properties were analyzed using tensile tests. Stretching was shown to be an important parameter for better CNF orientation and improved mechanical properties. Additionally, washing stage significantly increased tensile strengths of the filaments. The highest tensile strength was reached with washed S-CNF/CDAC-CNF, which was purely based on CNFs which were obtained through a green synthesis route in the deep eutectic solvent (DES). Overall, the results showed the technical feasibility of continuous process for fabrication of core-shell filaments based on functionalized nanocelluloses. However, further research is still needed to improve the CNF orientation and mechanical properties, and to develop the process by incorporating e.g. washing step.Tiivistelmä. Tämän diplomityön tarkoituksena oli tutkia uutta funktionalisoitujen nanoselluloosien rajapintakompleksointiin perustuvaa märkäkehruuprosessia ydin-kuori filamenttien tai lankojen valmistusta varten. Työ keskittyi märkäkehruuprosessin kehittämiseen ja työssä selvitettiin kuinka kelaus- ja kuivausvaiheet voisi yhdistää jatkuvatoimiseen prosessiin, jossa varaukseltaan vastakkaisista nanoselluloosista (CNF) valmistetaan filamentteja yhdistämällä rajapintakompleksointi ja märkäkehruu. Prosessin optimoimiseksi myös prosessiparametrien kuten kuivauslämpötilan, kehruunopeuden, neulan koon, pesun ja venytyksen vaikutuksia filamenttien mekaanisiin ominaisuuksiin tutkittiin. Jatkuvatoiminen prosessi kehitettiin kokeilemalla filamenteille erilaisia CNF ydin-kuori -yhdistelmiä ja yksikköoperaatiot liitettiin toisiinsa jatkuvien filamenttien valmistamiseksi. Työssä valmistettiin onnistuneesti kolme koostumukseltaan erilaista filamenttia, jotka koostuivat funktionalisoiduista anioninen-kationinen tai anioninen-anioninen CNF-pareista (S-CNF/CDAC-CNF, TO-CNF/CDAC-CNF, ja TO-CNF/TO-CNF). Filamenttien rakenne, joka muodostui anionisesta ytimestä ja kationisesta kuoresta, ilman poistaminen CNF:stä, filamenttien tukeminen ja kitkan vähentäminen prosessin aikana, kuivausilman oikea suuntaaminen sekä kelaimen Teflon-pinta olivat edellytys jatkuvatoimisen prosessin ja homogeenisten filamenttien valmistamisen kannalta. Lisäksi prosessin kehruunopeus, kuivauslämpötila ja neulan koko optimoitiin. Filamenttien rakennetta tutkittiin mikroskopialla ja lujuusmittausten avulla selvitettiin filamenttien mekaanisia ominaisuuksia. Venytyksen osoitettiin olevan tärkeä parametri CNF:n paremman orientaation ja mekaanisten ominaisuuksien kannalta. Lisäksi filamenttien peseminen paransi niiden vetolujuuksia. Paras vetolujuus saatiin pestylle S-CNF/CDAC-CNF filamentille, joka valmistettiin käyttämällä vihreitä syväeutektisia liuottimia (DES). Kaiken kaikkiaan tulokset osoittivat ydin-kuori filamenttien jatkuvatoimisen valmistuksen funktionalisoiduista nanoselluloosista olevan teknisesti mahdollista. Lisätutkimuksia kuitenkin tarvitaan CNF:n orientaation ja mekaanisten ominaisuuksien parantamiseksi sekä prosessin kehittämiseksi, esimerkiksi liittämällä pesuvaihe prosessiin

Series of configurational movements : User activities in technology generalization

The detailed studies of adoption and user activities indicate that continuous alterations accompany the proliferation of new technology, yet diffusion theory and system change-oriented frameworks portray the spread of technologies across a social or sociotechnical system with relatively few changes. To better reconcile the two orientations, we introduce a series of configurational movements (SCM) as a conceptual register for the generalization of new technology in society. We elaborate on the SCM with an over-a-decade-long investigation into heat pumps in Finland, one of the globally furthest progressed energy transitions. The process has thus far involved nine configurational movements, each featuring a change in the character of the technology, the ecology of actors relevant to it, and the contexts in which the technology spreads. SCM analysis further surfaces eight user activity types that have shaped how the technology, its deployment, and its markets have evolved: Adoption and routine use, adaption and adjustment, championing, user innovation, community building, peer intermediation, market creation and production of legitimating discourse on heat pumps. In all, the generalization features significant shifts in user practices, the technology, and societal impact throughout the process, not only during its early phases, instilling energy system wide change.© 2023 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioitu|en=peerReviewed

Navigating doctoral studies in Operations Management and Industrial Engineering

This short guidebook aims to address some frequently asked questions about doctoral studies in industrial management/industrial engineering and the related subjects. The purpose of this guide is to provide practical information with some background justification for each of the items. This is not a replacement for any university official instructions, degree structures or courses offered by the university. The contents of the guide consist of following: positioning what is our field of study, writing and defending a research plan, conducting a literature review and founding on theoretical framework, addressing questions related to research methods, discussing academic publications in conferences and journals, and outlining what constitutes a dissertation in a doctoral level. We hope that this book will demystify the process of doctoral studies, give practical advice of selecting the right journals, conferences, helping to handle review feedback, and other essential parts of the doctoral studies.fi=vertaisarvioimaton|en=nonPeerReviewed

Business models for enhanced solar photovoltaic (PV) adoption : Transforming customer interaction and engagement practices

Solar energy can play an important role in meeting global energy needs in a sustainable and environmentally friendly manner. However, despite solar energy’s accelerated growth in recent years, its level of diffusion is highly uneven when looked at on a global scale. The solar photovoltaic (PV) companies involved in the sales of PV systems are central to fostering diffusion. A company’s ability to devise and deliver value offerings that match customers’ needs is vital in encouraging the adoption of solar PV technology. The extent to which a company can address market needs and deliver value often depends on the business model it has adopted. The extant research has explored business models based on ownership structures, financing options, the effect of regulatory regimes and policies, industry practices, alliances, and business models for distributed generation and large-scale utility companies. However, the research to date, has mostly neglected the business models of solar companies involved in the sales and installation of solar PV. This qualitative study based on twenty semi-structured interviews contributes to the existing knowledge by exploring how sales and installation companies can enhance solar photovoltaic adoption by transforming customer interactions and engagement practices, which is a key element of a company’s business model. Companies’ ability to communicate value offerings and address consumer concerns is important in enhancing diffusion. The study highlights that transforming customer interaction and engagement practices can help companies broaden customer reach, improve the dissemination of information, reduce transaction costs and efficiently utilise market insights and trends.© 2024 The Authors. Published by Elsevier Ltd on behalf of International Solar Energy Society. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioitu|en=peerReviewed

Evaluation of novel protease enzymes on growth performance and apparent ileal digestibility of amino acids in poultry: enzyme screening

Three experiments were conducted to evaluate eight neutral and six acid proteases on growth performance and apparent ileal amino acid digestibility (AID) of poults (Experiment 1) or chicks (Experiments 2 and 3). Two basal diets were formulated: a nutrient adequate positive control (PC), which met or exceeded the nutrient requirements for poults (Experiment 1) or chicks (Experiments 2 and 3) and a negative control (NC) formulated to achieve 85% (Experiments 1 and 2) or 80% (Experiments 3) of the requirement for protein and amino acids. Phytase was included in all diets to provide 500 phytase units (FTU)/kg and xylanase was included in all diets to provide 10,000 (Experiments 1 and 2) or 16,000 (Experiments 3) xylanase units (BXU)/kg. Proteases were supplemented in the NC diet at an equivalent amount of enzyme protein to create 16 experimental diets. There were five birds/pen and 10 replicate pens per treatment in each experiment. In experiment 1, birds fed the PC diet gained more (P < 0.05) than birds fed the NC. There were no differences in growth performance in birds fed the PC or NC in experiments 2 or 3. In all three experiments, birds fed the NC supplemented with neutral protease 1 had reduced (P < 0.05) feed intake (FI) or body weight gain (BWG) and increased (P < 0.05) feed conversion ratio (FCR) compared with birds fed the NC. Birds fed the NC diet supplemented with neutral protease 3, 7 (Experiment 1), or acid protease 4 (Experiment 3) had increased (P < 0.05) FCR and birds fed neutral protease 6 (Experiment 2) had reduced (P < 0.05) BWG compared with birds fed the NC. Apparent ileal amino acid digestibility was improved (P < 0.05) with protease supplementation to the NC diets (Experiment 1 or 3), but this was dependent on the protease and the amino acid. In conclusion, novel protease supplementation improved AID of amino acids but this was not reflected in improvements in growth performance of poults or chicks

A Bayesian population model to estimate changes in the stock size in data poor cases using Mediterranean bogue (Boops boops) and picarel (Spicara smaris) as an example

The paper presents an effort to build a biologically realistic, age structured Bayesian model for the stock assessment of data poor fisheries where only aggregated catch data is available. The model is built using prior information from other areas and ecologically or taxonomically similar species. The modeling approach is tested with data poor fisheries on the Cyclades islands in Greek archipelago. The two most important species in the area are selected: bogue (Boops boops) and picarel (Spicara smaris). Both are hermaphroditic. The only data available is the total catch from 1950 to 2010. Information was gathered about natural mortality, recruitment, growth, body size, fecundity, and sex ratio. There were significant problems in finding reliable prior information and a uniform prior was used for fishing mortality. The models at their present stage are not used to give management advice. The biological characteristics of the species in that area should be further studied. However, the posteriors of biological parameters reflect the best available knowledge on these species and they could be used in future studies or in simpler biomass dynamics models as priors

Nesting Induced Peierls-type Instability for Compressed Li-CI16

Alkalies are considered to be simple metals at ambient conditions. However, recently reported theoretical and experimental results have shown an unexpected and intriguing correlation between complex structures and an enhanced superconducting transition temperature in lithium under pressure. In this article we analyze the pressure induced Fermi surface deformation in bcc lithium, and its relation to the observed cI16 structure. According to our calculations, the Fermi surface becomes increasingly anisotropic with pressure and develops an extended nesting along the bcc [121] direction. This nesting induces a phonon instability of both transverse modes at N, so that a Peierls-type mechanism is proposed to explain the stability of Li-cI16.Comment: Proceedings of Fukuoka 2006 Conference on Novel Pressure-induced Phenomena in Condensed Matter Systems. To be published in J. Phys. Soc. Jpn. 2 pages and 3 figure

(No) Time for Change : When and Why Entrepreneurs Act During Underperforming Fundraising Attempts

Entrepreneurs need to mobilize funds, but they do so under considerable uncertainty about resource holders’ preferences, leading often to fundraising attempts that perform below entrepreneurs’ aspirations. Past research has offered contrasting theorizing and evidence for why entrepreneurs then make changes to their product offering during such attempts as well as for why entrepreneurs refrain from taking such action. This paper develops and tests behavioral theory to reconcile this tension, explicating when and why entrepreneurs change their product offering during underperforming fundraising attempts. Specifically, we argue that entrepreneurs draw on three sources of information that are inherent to fundraising attempts and that inform the extent of their actions to change their product offering: the degree to which they perform below their own fundraising aspirations, the degree to which they fall below peer fundraising performance, and the time that remains until the deadline for the fundraising attempt. Longitudinal data on 576 fundraising campaigns (6,758 observations) published on the crowdfunding platform Kickstarter support our theory. By developing novel behavioral theory on when and why entrepreneurs take action during resource mobilization, we offer contributions to research on entrepreneurial resource mobilization, the crowdfunding literature, and the Behavioral Theory of the Firm.© 2023 The Author(s). This work is licensed under a Creative Commons Attribution-NonCommercialNoDerivatives 4.0 International License. You are free to download this work and share with others, but cannot change in any way or use commercially without permission, and you must attribute this work as Organization Science. https://doi.org/10.1287/orsc.2020.13803, used under a Creative Commons Attribution License: https://creativecommons.org/licenses/by-nc-nd/4.0/.fi=vertaisarvioitu|en=peerReviewed

Kelan järjestämien omaishoitajien kuntoutuskurssien arviointitutkimus

Kela järjestää harkinnanvaraisena kuntoutuksena kuntoutuskursseja omaishoitajille. Vuoden 2013 alusta kursseja lisättiin ja uudistettiin siten, että omaishoitajille tarkoitettujen yksilökurssien lisäksi järjestetään parikursseja omaishoitajalle ja hänen hoidettavalle läheiselleen. Tutkimuksen tavoitteena oli arvioida Kelan omaishoitajien kursseille ohjautumista, niistä saatua hyötyä sekä kurssien kehittämistarpeita. Kuntoutuskurssien hyötyä ja vaikutuksia kuntoutujien masennusoireisiin (BDI-II), elämänlaatuun (WHOQOL-BREF) sekä omaishoidon kuormittavuuteen (COPE-indeksi) arvioitiin näennäiskokeellisella asetelmalla vertailemalla ryhmiä, joista yksi osallistui omaishoitajien yksilökursseille (n = 64), yksi omaishoitajien parikursseille (n = 67), ja ryhmää joka ei osallistunut Kelan järjestämälle omaishoitajien kuntoutuskurssille (n = 49). Lisäksi analysoitiin kursseille osallistuneiden omaishoitajien asettamat GAS-tavoitteet. Vuoden kestäneen seurannan aikana vertailuryhmän kuormittuminen lisääntyi ja yksilökursseille osallistuneiden fyysinen elämänlaatu koheni tilastollisesti merkitsevästi. Vuoden aikana tapahtuneissa muutoksissa oli tilastollisesti merkitsevä ero siten, että vertailuryhmässä kuormittuminen lisääntyi suhteessa parikurssilaisiin (p = 0,047) ja elämänlaadun fyysisen osa-alueen keskiarvo heikkeni suhteessa parikurssilaisiin (p = 0,016) ja yksilökurssilaisiin (p = 0,010). Elämänlaadun ympäristön osa-alueen keskiarvo heikkeni vertailuryhmässä suhteessa yksilökurssilaisiin (p = 0,049). Omaishoitajien masennusoireissa ei ollut tilastollisesti merkitseviä muutoksia vuoden aikana eikä ryhmien välillä ollut eroja. Omaishoitajien kuntoutukselleen asettamista tavoitteista 2/3 lukeutui suoritukset ja osallistuminen -osa-alueelle. Kaikista tavoitteista saavutettiin 62 % ja tavoitteiden määrän mukaisen T-lukuarvon keskiarvo oli yksilökurssilaisilla 49,4 ja parikurssilaisilla 50,2. Suurimmat kehittämistarpeet liittyvät omaishoitajien kuntoutuskursseista tiedottamiseen, jotta kurssit pystyttäisiin kohdentamaan niitä eniten tarvitseville. Kuntoutuskursseihin sinänsä oltiin enimmäkseen tyytyväisiä. Kurssiohjelmassa on kehitettävää fyysisen aktivoinnin ja omaishoitotilanteen hallintaan liittyvissä sisällöissä. Läheisten ohjelmaa parikursseilla olisi hyvä kehittää. Parikurssit ovat tervetullut lisä Kelan kuntoutuskurssivalikoimaan. Monelle omaishoitajalle ne ovat ainoa mahdollisuus osallistua kuntoutukseen ja omaishoitajien kuormittumista pystytään ehkäisemään paremmin, kun läheinen osallistuu kuntoutukseen. Omaishoitajien kuntoutuskursseilla saavutettiin edistymistä omaishoitajien elämänlaadussa. Masennusoireiden vähentämiseksi saatetaan tarvita lisäksi muita tukitoimia kuin kurssimuotoinen kuntoutus