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Nowadays, additive manufacturing, known as 3D printing, is vigorously employed at various enterprises due to the ability of industrial series production and customization in conjunction with geometry freedom. While, material design and fabrication of composite materials, meeting the desired architecture and properties, is another promising application of additive manufacturing. For instance, additive manufacturing of the material exhibiting electrochemical properties is beneficial for the development of freestanding electrodes that might be used in electrochemical energy storage systems. Herein, the graphite/nylon composite with a high carbon ratio of 30 wt% was produced by laser powder bed fusion to promote the development of the additive manufacturing of electrochemical energy storage devices. The material characterization of the additively manufactured graphite/nylon electrode demonstrates the porous structure with uniform distribution of the compounds, and the absence of chemical interactions between them during laser powder bed fusion. The electrochemical properties of the composite were investigated in acidic, neutral, and alkaline electrolytes. The tested additively manufactured electrodes demonstrate a capacitive behaviour and a stable electrochemical performance with average capacitance retention of 95%. The findings open new frontiers for the development and improvement of the production of electrochemically active materials by additive manufacturing with consideration to design freedom and customization. peerReviewed

For a long time, there has been a worldwide shortage of organ donations with hundreds of thousands of people suffering from prolonged waiting times. In addition, the current in vitro platforms for drug development and modelling of diseases, require a rapid upgrade towards more biologically relevant, three-dimensional (3D) systems. Tissue engineering (TE) of 3D scaffolds aims to solve these issues by fabrication of tissues and even organs in vitro with suitable biomaterials and fabrication techniques. 3D printed polymeric structures in combination with suitable biocompatible hydrogels results in 3D hydrogel constructs suitable for TE applications. This thesis work had three aims. First was to develop a 3D printed PVA mesh. Second aim was to prepare a robust, optimally crosslinked liver dECM hydrogel. And the third aim was to combine the mesh and the hydrogel into a cell culturing platform for liver hepatocytes. At first, a 3D model was developed, according to which a 4-layer PVA mesh was 3D printed. The solubilization kinetics of the mesh in phosphate buffer saline (PBS), were determined by measuring the diffraction over time. Full dissolution was observed within 180 min. Next, the dECM hydrogel was prepared form porcine liver and the decellularization deemed successful as over 99 % of the DNA was removed in relation to native liver. From the dECM, 4 different hydrogels with varying degrees of crosslinking were prepared: non-pH adjusted, pH adjusted, one crosslinked with succinimidyl valerate-polyethylene glycol-succinimidyl valerate (SVA-PEG-SVA), and one with crosslinkers SVA-PEG-SVA and tyrosinase. The addition of crosslinkers SVA-PEG-SVA and tyrosinase led to highest degree of crosslinking, confirmed with Trinitrobenzenesulfonic acid (TNBS) assay. With scanning electron microscopy (SEM), the effect of crosslinking on the gels’ porosity was determined, with denser porosity observed with higher degree of crosslinking. Viscosity and gelation kinetics of the hydrogels were determined by rheological measurements. These results were in line with TNBS-, and SEM results, with higher viscosity associated to higher degree of crosslinking. Additionally, all gels presented shear thinning. The gelation kinetics results showed that the addition of SVA-PEG-SVA and tyrosinase induced the slowest overall crosslinking. For the cell viability studies, liver HepG2 cells were encapsulated into the SVA-PEG-SVA and tyrosinase crosslinked hydrogel, and casted over the PVA mesh. The viability of the HepG2 cells was determined with Live/Dead assay and with alamarBlue assay. Both assays provided results of increased cell viability and proliferation. AlamarBlue assay showed exponential increase of viability between days 1 and 7, supported by the findings form Live/Dead assay. In this thesis, TE methods were deployed to develop a cell culture platform from liver dECM hydrogel with integrated 3D printed PVA mesh. The effect of additional crosslinkers on the dEMC gel were determined for optimal composition and properties. The platform was observed to support HepG2 cell proliferation over 7 days period. Maailmanlaajuisen elinluovutuspulan vuoksi sadat tuhannet ihmiset kärsivät pitkittyneistä odotusajoista. Myös lääkekehitys ja sairauksien tutkiminen vaativat nopeaa kehitystä kohti kolmiulotteisten (3D) biologisesti relevanttien in vitro-kudosmallien käyttöä. Kudosteknologian avulla näihin ongelmiin voidaan tarjota ratkaisuja valmistalla in vitro-ympäristössä kudoksia matkivia 3D-rakenteita ja tulevaisuudessa jopa elimiä. Tällöin erilaiset biomateriaalit ja valmistusmenetelmät ovat keskeisessä roolissa. Valmistettavien rakenteiden sisäistä ja ulkoista geometriaa voidaan hallita 3D-tulostuksen avulla. Kyseisellä menetelmällä valmistettujen polymeerirakenteiden ja bioyhteensopivien hydrogeelien yhdistelmiä on mahdollista käyttää kudosteknologisissa sovelluksissa. Opinnäytetyöllä oli kolme tavoitetta. Ensimmäiseksi tuli suunnitella ja 3D-tulostaa poly-vinyylialkoholi (PVA)-ristikko. Toisena tavoitteena oli valmistaa optimaalisesti ristisilloitettu hydrogeeli maksan soluttomasta ekstrasellulaarisesta matriisista (dECM). Kolmantena tavoitteena oli valmistaa soluviljelyalusta maksan syöpäsoluille integroimalla PVA-ristikko dECM-hydrogeeliin. Aluksi kehitettiin 3D-malli, minkä mukaan 3D-tulostettiin nelikerroksinen PVA-ristikko, jonka liukoisuuskinetiikka selvitettiin mittaamalla diffraktiota fosfaattipuskurisuolaliuoksessa (PBS). Totaalisen liukenemisen havaittiin tapahtuneen 180 minuutissa. Seuraavaksi dEMC-hydrogeeli valmistettiin poistamalla solut sian maksakudoksesta. Menetelmä todettiin onnistuneeksi, koska yli 99 % DNA:sta oli poistettu verrattaessa natiiviin maksakudokseen. DECM:stä valmistettiin neljä eri ristisilloitusasteista hydrogeeliä: ei-pH-neutraloitu, pH-neutraloitu, yksi ristisilloitettu sukkinimidyylivaleraatti-polyetyleeniglykoli-sukkinimidyylivaleraatilla (SVA-PEG-SVA) ja yksi ristisilloitettu SVA-PEG-SVA:lla sekä tyrosinaasilla. Kahden ristisilloittajan lisääminen johti suurimpaan ristisilloitusasteeseen, joka havaittiin trinitrobentseenisulfonihappo (TNBS)-määrityksellä. Ristisilloituksen vaikutus geelien huokoisuuteen määritettiin pyyhkäisyelektronimikroskopialla (SEM). Tulosten mukaan ristisilloitusaste oli kääntäen verrannollinen huokoisuuteen. Hydrogeelien viskositeetti ja geeliytymiskinetiikka määritettiin reologisilla mittauksilla. Viskositeetin ja ristisilloitusasteen huomattiin olevan suoraan verrannollisia. Lisäksi kaikkien hydrogeelien havaittiin olevan leikkausohenevia. Geeliytymiskinetiikan tulokset osoittivat, SVA-PEG-SVA:n ja tyrosinaasin lisäämisen aiheuttavan hitaimman kokonaisvaltaisen ristisilloituksen. Reologisten mittausten tulokset olivat linjassa TNBS- ja SEM-tulosten kanssa. Lopulta tutkittiin dECM-hydrogeelin ja PVA-ristikon bioyhteensopivuutta. Maksan HepG2-syöpäsoluja sekoitettiin SVA-PEG-SVA- ja tyrosinaasi-ristisilloitettuun hydrogeeliin, joka valettiin ristikon päälle. Solujen proliferaatio määritettiin alamarBlue- ja Live/Dead-menetelmillä. AlamarBlue osoitti proliferaation eksponentiaalisen lisääntymisen päivien 1 ja 7 välillä, mitä tukivat Live/Dead-menetelmän tulokset. Tässä opinnäytetyössä kudosteknologisilla menetelmillä kehitettiin soluviljelyalusta maksan dECM-hydrogeelistä ja 3D-tulostetusta PVA-ristikosta. Ristisilloittajien vaikutus dEMC-hydrogeeliin määritettiin optimaalisen koostumuksen ja ominaisuuksien saamiseksi. Lopuksi soluviljelyalustan havaittiin tukevan HepG2-solujen proliferaatiota 7 päivän ajan.

In this paper, we offer three examples from our research projects on both technological and pedagogical innovations to illustrate the impact of rapid technology changes on research. Members of our research team both developed and used technology applications in their research projects, utilizing design-based research (DBR). During the experiments, we encountered new challenges by the end of the research cycle due to updates in technologies. Although we had an idea of how to redesign the project for the next cycle based on the analyses of data, we noticed that we needed to not only redesign our approaches based on the research results but the changes in technologies were so rapid that materials and pedagogies needed to be altered as well. In our article, we propose an additional aspect to be considered in DBR while researching technology integration or innovative technologies. Moreover, the rapid change in technology raises further challenges to teachers’ professional development and the integration of those innovative technologies in classrooms. We anticipate our work to contribute to the development of technology resources and related pedagogies as well as the refinement of research methodologies in technology environments. Our contributions for the development of technology resources and refinement of research methods in technology-supported learning environments should, among other things, contribute to a less complex and at the same time more sustainable integration of pedagogical innovations into scientific and school practices. peerReviewed

A selective method for preconcentration and determination of methylmercury (MeHg) and inorganic mercury (iHg) in natural water samples at the ng L−1 level has been developed. The method involves adsorption of Hg species into a 3D printed metal scavenger and sequential elution with acidic thiourea solutions before ICP-MS determination. Experimental parameters affecting the preconcentration of MeHg and iHg such as the sample matrix, effect of the flow rate on adsorption, eluent composition, and elution mode have been studied in detail. The obtained method detection limits, considering the preconcentration factors of 42 and 93, were found to be 0.05 ng L−1 and 0.08 ng L−1 for MeHg and iHg, respectively. The accuracy of the method was assessed with a certified groundwater reference material ERM-CA615 (certified total iHg concentration 37 ± 4 ng L−1). The determined MeHg concentration was below MDL while iHg concentration was determined to be 41.2 ± 0.5 ng L−1. Both MeHg and iHg were also spiked to natural water samples at 5 ng L−1 concentration and favorable spiking recoveries of 88–97% were obtained. The speciation procedure was successfully applied to two lake water samples where MeHg and iHg concentrations ranged from 0.18 to 0.24 ng L−1 and 0.50–0.62 ng L−1, respectively. The results obtained demonstrate that the developed 3D printed metal scavenger-based method for preconcentration and speciation of Hg is simple and sensitive for the determination of Hg species at an ultra-trace level in water samples. peerReviewed

Open in a separate window Three-dimensional selective laser sintering printing was utilized to produce porous, solid objects, in which the catalytically active component, Pd/SiO2, is attached to an easily printable supporting polypropylene framework. Physical properties of the printed objects, such as porosity, were controlled by varying the printing parameters. Structural characterization of the objects was performed by helium ion microscopy, scanning electron microscopy, and X-ray tomography, and the catalytic performance of the objects was tested in the hydrogenation of styrene, cyclohexene, and phenylacetylene. The results show that the selective laser sintering process provides an alternative and effective way to produce highly active and easily reusable heterogeneous catalysts without significantly reducing the catalytic efficiency of the active Pd/SiO2 component. The ability to control the size, porosity, mechanical properties, flow properties, physical properties, and chemical properties of the catalyst objects opens up possibilities to optimize devices for different reaction environments including batch reactions and continuous flow systems.

In this paper, the ability to 3D print lithium-ion batteries through thermoplastic material extrusion and polymer powder bed fusion is considered. Focused on the formulation of positive electrodes composed of polypropylene, LiFePO4 as active material, and conductive additives, advantages and drawbacks of both additive manufacturing technologies, are thoroughly discussed from the electrochemical, electrical, morphological and mechanical perspectives. Based on these preliminary results, strategies to further optimize the electrochemical performances are proposed. Through a comprehensive modeling study, the enhanced electrochemical suitability at high current densities of various complex three-dimensional lithium-ion battery architectures, in comparison with classical two-dimensional planar design, is highlighted. Finally, the direct printing capability of the complete lithium-ion battery by means of multi-materials printing options processes is examined. peerReviewed

In this study, we develop mathematical educational practices for students to explore ancient buildings using GeoGebra, Augmented Reality and 3D printing. It is an interdisciplinary approach, intertwining history, culture, mathematics, and engineering. For example, the 3D modelling of Cheomseongdae in Korea and the Temple of Dendera in Egypt can enable students to practice a multimodal set of traditional and innovative learning approaches. Students might use their mathematical knowledge to reflect on architectural and cultural history in a modeling task.

Selective laser sintering (SLS) 3D printing was utilized to fabricate highly porous carbonous electrodes. The electrodes were prepared by using a mixture of fine graphite powder and either polyamide-12, polystyrene, or polyurethane polymer powder as SLS printing material. During the printing process the graphite powder was dispersed uniformly on the supporting polymer matrix. Graphite’s concentration in the mixture was varied between 5 and 40 wt % to find the correlation between the carbon content and conductivity. The graphite concentration, polymer matrix, and printing conditions all had an impact on the final conductivity. Due to the SLS printing technique, all the 3D printed electrodes were highly porous. By using polyurethane as the supporting matrix it was possible to produce flexible electrodes in which the conductivity is sensitive to pressure and mechanical stress. Physical properties such as graphite distribution, attachment, and the overall porosity of the printed electrodes were studied using scanning electron microscopy (SEM), helium ion microscopy (HIM), and X-ray tomography. The results show that the combination of chemical design of the printing material and the utilization of SLS 3D printing enables fabrication of highly customizable electrodes with desired chemical, physical, mechanical, and flow-through properties. peerReviewed

Selective laser sintering (SLS) 3d printing was utilized to manufacture a solid catalyst for Suzuki-Miyaura cross-coupling reactions from polypropylene as a base material and palladium nanoparticles on silica (SilicaCat Pd(0)R815-100 by SiliCycle) as the catalytically active additive. The 3d printed catalyst showed similar activity to that of the pristine powdery commercial catalyst, but with improved practical recoverability and reduced leaching of palladium into solution. Recycling of the printed catalyst led to increase of the induction period of the reactions, attributed to the pseudo-homogeneous catalysis. The reaction is initiated by oxidative addition of aryl iodide to palladium nanoparticles, resulting in formation of soluble molecular species, which then act as the homogeneous catalyst. SLS 3d printing improves handling, overall practicality and recyclability of the catalyst without altering the chemical behaviour of the active component.

Luukudos on heti veren jälkeen maailman käytetyin kudossiirre ja väestön ikääntyessä luusiirteiden tarpeen odotetaan nousevan nykyisestä. Mittavista panostuksista huolimatta biomateriaalikehityksessä ja -tutkimuksessa, potilaiden hoidossa synteettisiä luusiirteitä käytetään huomattavasti vähemmän kuin autologisia luusiirteitä. Uusien synteettisten luusiirteiden kehityksessä tarvitaan tehokkaita ja luotettavia soluviljelymenetelmiä arvioimaan materiaalien kykyä tukea luun ja verisuonien muodostumista. Aikuisen kantasolut, kuten rasvakudoksen ja luuytimen kantasolut, jotka pystyvät erilaistumaan sekä luusoluiksi, että verisuonten endoteelisoluiksi, ovat erinomainen työkalu tähän tarkoitukseen. Toimivia ja kustannustehokkaita menetelmiä luu- ja endoteelierilaistukseen täytyy kuitenkin vielä kehittää. Tämä väitöskirjassa tutkitaan strategioita aikuisen kantasolujen erilaistukseen 3-ulotteisessa ympäristössä, jotta uusien synteettisten luusiirteiden soveltuvuutta voidaan arvioida luotettavasti. Kahta kliinisessä käytössä olevaa synteettistä luusiirremateriaalia (BoneCeramic kalsiumfosfaatti ja BioRestore bioaktiivinen lasi) verrattiin rasvakudoksen kantasoluviljelmissä. Samalla tutkittiin yleisesti käytettyjen kasvutekijöiden luun morfogeneettisten proteiinien (BMP)-2, BMP-7 ja verisuonen endoteelin kasvutekijän (VEGF) tehokkuutta rasvakudoksen kantasolujen luuerilaistuksessa. Koska kovien ja hauraiden keraamien istuttaminen siirrekohtaan leikkauksen aikana on vaikeaa ja ne sopivat huonosti kuormaakantaviin kohtiin, tutkimuksessa kehitettiin elastinen β-trikalsiumfosfaatti/poly(L-laktidi-ko-ε-kaprolaktoni) (βTCP/PLCL) komposiitti hyödyntäen ylikriittistä hiilidioksidi prosessointia. Näiden komposiittien kykyä tukea luun ja verisuonten muodostumista tutkittiin sekä rasvakudoksen kantasoluviljelmissä, että kanin reisiluun puutoksessa. Seuraavaksi kehitettiin 3D tulostuksen avulla polykaprolaktoni (PCL)/bioaktiivinen lasi-kupari – komposiitti, jonka soluyhteensopivuutta sekä kykyä tukea luun ja verisuonten muodostumista tutkittiin luuytimen kantasolujen viljelyssä sekä luuytimen kantasolujen ja napanuoran endoteelisolujen yhteisviljelyssä. BoneCeramic kalsiumfosfaatti ja BioRestore bioaktiivinen lasi vaikuttivat eri tavalla rasvakudoksen kantasoluihin: kalsiumfosfaattirakeet lisäsivät luuerilaistumista, kun taas bioaktiivinen lasi stimuloi solujen jakautumista. Luuerilaistusliuos oli merkittävästi tehokkaampi luuerilaistaja verrattuna kasvutekijöihin rasvakudoksen kantasolujen erilaistuksessa. Rasvakudoksen kantasolut eivät herkistyneet kasvutekijöille myöskään silloin, kun kasvutekijät yhdistettiin luuerilaistuliuokseen. Kehitetyt β-TCP/PLCL komposiitit tukivat rasvakudoksen kantasolujen elinkykyä, jakautumista ja luuerilaistumista. Rasvakudoksen kantasolut kykenivät erilaistumaan sekä luu- että endoteelisolujen suuntaan komposiiteilla, kun niitä viljeltiin endoteelierilaistusliuoksessa, mutta erilaistuminen jäi vaillinaiseksi. Luu- ja endoteelierilaistusliuosten sekoituksen näytettiin tukevan solujen luu- mutta ei endoteelierilaistumista. Kun komposiitti istutettiin kanin reisiluun puutokseen, luukudoksen todettiin kasvavan komposiitin pinnalla ja sen sisällä jo 4 viikkoa istutuksen jälkeen. Lisäksi se ei aiheuttanut tulehdusta tai saanut aikaan sidekudoksen tai kystien muodostusta. Kasvavalla kuparipitoisuudella huomattiin olevan sytotoksinen vaikutus luuytimen kantasoluihin, kun soluja viljeltiin PCL/bioaktiivinen lasi-kupari komposiiteilla. PCL/bioaktiivinen lasi komposiitti tuki hyvin luuerilaistumista, kun taas kuparin lisääminen heikensi komposiitin luun muodostuskykyä. Molemmat komposiitit tukivat verisuonirakenteiden muodostumista luuytimen kantasolujen ja napanuoran endoteelisolujen yhteisviljelyssä; kuparilla ei huomattu olevan merkittävää vaikutusta verisuonittumiseen. Yhteenvetona luuerilaistusliuos on tehokkaampi luuerilaistaja 3-ulotteisessa ympäristössä kuin yleisesti käytetyt kasvutekijät rasvakudoksen kantasoluille. Huokoinen β-TCP/PLCL komposiitti on lupaava synteettinen luusiirre, sillä se on kudosyhteensopiva, luunkasvua johtava ja sitä on helppo käyttää ja muokata leikkauksen aikana. Lisäksi komposiitti tukee rasvakudoksen kantasolujen endoteelierilaistumista, kun niitä viljellään endoteelierilaistusliuoksessa, mutta solujen erilaistus ei kehity kypsien endoteelisolujen tasolle 3 viikon erilaistuksen aikana. Tulostettu PCL/bioaktiivinen lasi komposiitti tukee luuerilaistumista sekä verisuonittumista, mutta kuparin lisääminen komposiittiin heikentää luuerilaistumista eikä paranna verisuonittumista. Tämä tutkimus osoittaa, että yhdistämällä luunkasvua johtavia keraameja synteettisiin polymeereihin voidaan luoda hyvin lupaavia, elastisia synteettisiä luusiirremateriaaleja verrattuna koviin keraameihin. Bone tissue is the second most common tissue transplant after blood transfusion and as people age, the need for bone transplants is expected to rise even more. Despite the great efforts in biomaterial research and development, autologous bone remains the benchmark among bone grafts whereas synthetic bone grafts are still less-used. Effective and reliable development of synthetic bone grafts require efficient cellular assessments in vitro including the evaluation of osteogenic as well as vasculogenic potential of the scaffolds. Adult stem cells, including human adipose stem cells (hASCs) and human bone marrow stem cells (hBMSCs), provide an excellent tool for this as they have been shown to differentiate to bone-forming cells and endothelial cells. However, efficient and cost-effective approaches to induce osteogenic and endothelial differentiation are still needed. This thesis focuses on the study and development of in vitro differentiation strategies for hASCs and hBMSCs in 3-dimensional (3D) culture in order to study and verify the feasibility of novel bone substitute materials. Firstly, two clinically used synthetic bone graft scaffolds, BoneCeramic composed of biphasic calcium phosphate and BioRestore composed of bioactive glass (BaG), were compared in hASC culture and, the effectiveness of commonly used growth factors bone morphogenetic protein (BMP)-2, BMP-7 and vascular endothelial growth factor (VEGF) on hASC osteogenesis were compared to OM. As ceramics are hard and brittle making them difficult to implant and undesirable to load-bearing sites, an elastic β-tricalciumphosphate/poly(L-lactide-co-ε-caprolactone) (βTCP/PLCL) composite was developed using supercritical CO2 (scCO2) foaming. The capacity of the composites to support hASC osteogenesis and vasculogenesis were studied in vitro in hASC culture and in vivo in rabbit femur defect. Finally, 3D printed polycaprolactone (PCL)/copper-doped BaG composites were developed and their osteogenic and vasculogenic potential was studied in vitro in hBMSC culture and in a co-culture of hBMSCs and human umbilical vein endothelial cells (HUVECs). The two biomaterial scaffolds BoneCeramic and BioRestore demonstrated differential effects on hASCs: BoneCeramic induced ALP activity and collagen production of hASCs, while BioRestore stimulated hASC proliferation. In comparison to the growth factors, OM was more effective in the osteogenic differentiation of hASCs in vitro in BoneCeramic and BioRestore. On the other hand, combining the growth factors with OM did not sensitize hASCs to the growth factors. The β-TCP/PLCL composites supported the viability, proliferation and osteogenic differentiation of hASCs reliably in vitro. When studying the osteogenic and endothelial differentiation of hASCs in β-TCP/PLCL composites, hASCs differentiated towards both lineages when cultured in endothelial medium (EM) although the differentiation was left in a premature state. Culture in a cocktail medium of OM and EM supported osteogenic but not endothelial differentiation of hASCs. The in vivo study confirmed biocompatibility as well as osteoconductivity of the composite as no inflammation, fibrous tissue or cyst formation was detected and, native bone tissue was able to grow on and in the β-TCP/PLCL composite already at 4 weeks. In the evaluation of 3D printed PCL/BaG-Cu composites, copper was observed to have a dose-dependent cytotoxic effect on hBMSCs in vitro. The PCL/BaG composite induced hBMSC osteogenesis while the addition of copper in BaG had an inhibiting effect on the osteogenic differentiation of hBMSCs. In co-culture of hBMSCs and HUVECs, both PCL/BaG and PCL/BaG-Cu scaffolds supported tubule formation, but the added copper did not boost the vasculogenic effect of the composite. In conclusion, OM was shown to be a cost-effective osteogenic stimulant in 3D culture as compared to exogenously added growth factors. The feasibility of the scCO2 foamed β-TCP/PLCL composite as potential a bone graft for clinical use was evidenced in vitro and in vivo. The 3D printed PCL/BaG composite showed promise in supporting osteogenesis in vitro whereas the addition of copper hindered the osteogenic effect of the composite. Both PCL/BaG and PCL/BaG-Cu composites supported tubule formation in hBMSC+HUVEC co-culture but the copper did not induce the vasculogenic effect of the composite. To conclude, the elastic and bioactive synthetic polymer -based composites consisting osteoconductive ceramics are highly promising alternatives for synthetic bone grafts when compared to hard ceramics.

Three-dimensionally printed solid but highly porous polyamide-12 (PA12) plate-like filters were used as selective adsorbents for capturing tetrachloroaurate from acidic solutions and leachates to prepare PA12–Au composite catalysts. The polyamide-adsorbed tetrachloroaurate can be readily reduced to gold nanoparticles by using sodium borohydride, ascorbic acid, hydrogen peroxide, UV light, or by heating. All reduction methods led to polyamide-anchored nanoparticles with an even size distribution and high dispersion. The particle sizes were somewhat dependent on the reduction method, but the average diameters were typically about 20 nm. Particle sizes were determined by using a combination of single-particle inductively coupled plasma mass spectrometry, helium ion microscopy, and powder X-ray diffraction. Dispersion of the particles was analyzed by scanning electron microscopy with energy-dispersive spectroscopy. Due to the high adsorption selectivity of polyamide-12 toward tetrachloroaurate, the three-dimensional-printed filters were first used as selective gold scavengers for the acidic leachate of electronicwaste (WEEE). The supported nanoparticles were then generated directly on the filter via a simple reduction step. These objects were used as catalysts for the reduction of 4-nitrophenol to 4-aminophenol. The described method provides a direct route from waste to catalysts. The selective laser sintering method can be used to customize the flow properties of the catalytically active filter object, which allows the optimization of the porous catalytic object to meet the requirements of catalytic processes. peerReviewed

In the future, the number and complexity of products made using additive manufacturing (AM) techniques will increase rapidly. The development of softwares and algorithms related to processes will eliminate extra intermediate steps between the product design and the end product, and will finally give us more intelligent way to manufacture these new products. More efficient 3D printing processes will enable the production of cheaper individual items and, furthermore, they will increase the demand for these high - quality tailored unrivalled solutions. The market potential is huge. However, at present the fundamentals of the area are only lightly studied and several key challenges concerning structural behavior and performance have to be solved before these techniques can be used in a widespread, cost - effective manner. Success in this task creates a basis for mathematical modeling and design, which will considerably accelerate the development time cycle of consumer products. With new computational methods becoming even more sophisticated and faster, the repeatability and reliability of the product design process will improve, enabling further production quality advances in the manufacturing industry. 3D printing assisted by Artificial Intelligence (AI) will become one of the major components of concept of ’Industry 4.0’ approaching independently operating and even self - contained systems. nonPeerReviewed

Selective laser sintering (SLS) 3D printing is used to fabricate highly macroporous ion scavenger filters for recovery of Pd and Pt from electronic waste. The scavengers are printed by using a mixture of polypropylene with 10 wt% of type‐1 anion exchange resin. Porosities and the flow‐through properties of the filters are controlled by adjusting the SLS printing parameters. The cylinder‐shaped filters are used in selective recovery of Pd and Pt from acidic leachate of electronic waste simply by passing the solution through the object. Under such conditions, the scavenger filters are able to capture Pd and Pt as anionic complexes with high efficiency from a solution containing mixture of different metal ions. By using the Pd/Pt scavenger together with previously reported, highly selective nylon‐based Au scavenger, precious metals, i.e., Au, Pd, and Pt could all be recovered from the electronic waste leachate in a single flow‐through process. One of the main advantages of the printed scavengers is that all recovered metals can be easily extracted from the filters as separate fractions by using aqueous solutions of thiourea or diluted nitric acid. After removal of the captured metals, the scavengers are reusable without significant loss of their ion‐capturing performance. peerReviewed

The development of additive manufacturing (AM) technology is expected to transform product design and manufacturing. It is predicted that the effects of AM on business will be diverse and extensive. It will be critical for business owners to observe how AM impacts on conventional supply chains and business networks, plus the effects on customers’ value propositions and on value creation. Value creation and value capture are concepts strongly linked to business relations and to stakeholder management. However, the concept of value is inherently complex and multifaceted, and so are the structures within which value potential exists in business networks and business environments. The critical issue for business managers is to identify where and how value is created in business relations. In this study, the primary purpose was to observe how AM technology impacts on company value creation within complex business relations. peerReviewed

1800-luvun lopulla Englannissa syntynyt Arts and Crafts -liike halusi tehdä taiteesta ja tuotannosta demokraattisempaa. Liikkeen merkittävin edustaja oli runoilija, käsityöläinen ja sosialisti William Morris. Nykypäivänä avoimen lähdekoodin filosofia ja vertaistuotantotavat yhdistettynä 3D-tulostusteknologiaan edustavat samankaltaista filosofiaa tuotannon demokratisoinnista kuin Arts and Crafts -liike 1800-luvulla. 3D-tulostus on uusi teknologia, jolla tietokonemalleista voidaan helposti luoda fyysisiä kappaleita. Arts and Crafts -liike vastusti konetyötä, joten kysymys koneen roolista taiteen tuhoajana ja taiteen pelastajana 1800-luvun lopulta nykypäivään on tutkimuksessani keskeinen. Tutkin Arts and Crafts -liikettä erityisesti sen isähahmon William Morrisin luentojen pohjalta mutta pohdin myös muiden ajattelijoiden tekstejä. 3D-tulostuksen ollessa vielä hyvin uusi teknologia pohjaan tutkimukseni siitä akateemisten artikkelien ohella myös uutisartikkeleihin, populäärikirjallisuuteen, videoituihin luentoihin sekä itse tekemiini haastatteluihin. Vertaistuotantoa sekä avointa lähdekoodia käsittelevät jaksot perustuvat akateemiseen kirjallisuuteen. Tutkimukseni on kulttuurikritiikkiä ja sovellan siinä vertailevaa analyysiä. Arts and Crafts -liikettä, 3D-tulostusta ja siihen liittyviä filosofioita yhdistävät halu tuoda tavaratuotanto lähemmäksi tavallista ihmistä. Niitä yhdistävät myös ajatukset vapaasta yhteistoiminnasta, laadun tavoittelusta voittojen sijaan sekä eräänlainen sosialismi. Uuden teknologian myötä tulevaisuudessa saattaa ilmetä kehitystä Arts and Crafts -liikkeen toivomaan suuntaan. Taiteen, käsityön ja konetyön käsitteet ovat jatkuvassa muutoksessa. Lewis Mumfordin käsitteiden pohjalta voidaan väittää, että koneen rooli taiteen tuhoajana tai pelastajana on riippuvainen koneen käyttäjän ideologiasta tai filosofiasta.