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  • 1.
    Abrahamsen, Rune
    et al.
    Moelven Limtre, Norway.
    Bjertnaes, Magne A.
    Sweco, Norway.
    Bouillot, Jacques
    Eiffage, France.
    Brank, Bostjan
    University of Ljubljana, Slovenia.
    Cabaton, Lionel
    Arbonis, France.
    Crocetti, Roberto
    Moelven, Sweden.
    Flamand, Olivier
    CSTB, France.
    Garains, Fabien
    Eiffage, France.
    Gavric, Igor
    InnoRenew, Slovenia.
    Germain, Olivier
    Galeo, France.
    Hahusseau, Ludwig
    Eiffage, France.
    Hameury, Stephane
    CSTB, France.
    Johansson, Marie
    RISE, Sweden.
    Johansson, Thomas
    Moelven, Sweden.
    Ao, Wai Kei
    University of Exeter, UK.
    Kurent, Blaz
    University of Ljubljana, Slovenia.
    Landel, Pierre
    RISE, Sweden.
    Linderholt, Andreas
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Malo, Kjell
    NTNU Norwegian University of Science and Technology, Norway.
    Manthey, Manuel
    CSTB, France.
    Nåvik, Petter
    Sweco, Norway.
    Pavic, Alex
    University of Exeter, UK.
    Perez, Fernando
    Smith and Wallwork, UK.
    Rönnquist, Anders
    NTNU Norwegian University of Science and Technology, Norway.
    Stamatopoulos, Haris
    NTNU Norwegian University of Science and Technology, Norway.
    Sustersic, Iztok
    InnoRenew, Slovenia.
    Tulebekova, Salue
    NTNU Norwegian University of Science and Technology, Norway.
    Dynamic Response of Tall Timber Buildings Under Service Load: The DynaTTB Research Program2020In: EURODYN 2020, XI international conferece on structural dynamics: Proceedings, Volym II / [ed] M. Papadrakakis, M. Fragiadakis, C. Papadimitriou, National Technical University of Athens , 2020, p. 4900-4910Conference paper (Refereed)
    Abstract [en]

    Wind-induced dynamic excitation is becoming a governing design action determin-ing size and shape of modern Tall Timber Buildings (TTBs). The wind actions generate dynamic loading, causing discomfort or annoyance for occupants due to the perceived horizontal sway – i.e. vibration serviceability failure. Although some TTBs have been instrumented and meas-ured to estimate their key dynamic properties (natural frequencies and damping), no systematic evaluation of dynamic performance pertinent to wind loading has been performed for the new and evolving construction technology used in TTBs. The DynaTTB project, funded by the Forest Value research program, mixes on site measurements on existing buildings excited by heavy shakers, for identification of the structural system, with laboratory identification of building elements mechanical features coupled with numerical modelling of timber structures. The goal is to identify and quantify the causes of vibration energy dissipation in modern TTBs and pro-vide key elements to FE modelers.

    The first building, from a list of 8, was modelled and tested at full scale in December 2019. Some results are presented in this paper. Four other buildings will be modelled and tested in spring 2020.

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  • 2.
    Acharya, Sarthak
    et al.
    Luleå University of Technology, Sweden;Univ Oulu, Finland.
    Sattar, Shahid
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Chouhan, Shailesh Singh
    Luleå University of Technology, Sweden.
    Delsing, Jerker
    Luleå University of Technology, Sweden.
    Detailed Characterization of a Fully Additive Covalent Bonded PCB Manufacturing Process (SBU-CBM Method)2022In: Processes, ISSN 2227-9717, Vol. 10, no 4, article id 636Article in journal (Refereed)
    Abstract [en]

    To bridge the technology gap between IC-level and board-level fabrications, a fully additive selective metallization has already been demonstrated in the literature. In this article, the surface characterization of each step involved in the fabrication process is outlined with bulk metallization of the surface. This production technique has used polyurethane as epoxy resin and proprietary grafting chemistry to functionalize the surface with covalent bonds on an FR-4 base substrate. The surface was then metalized using an electroless copper (Cu) bath. This sequential growth of layers on top of each other using an actinic laser beam and palladium (Pd) ions to deposit Cu is analyzed. State-of-the-art material characterization techniques were employed to investigate process mechanism at the interfaces. Density functional theory calculations were performed to validate the experimental evidence of covalent bonding of the layers. This manufacturing approach is capable of adding metallic layers in a selective manner to the printed circuit boards at considerably lower temperatures. A complete analysis of the process using bulk deposition of the materials is illustrated in this work.

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  • 3.
    Addassi, Mouadh
    et al.
    Technical University of Denmark, Denmark.
    Johannesson, Björn
    Linnaeus University, Faculty of Technology, Department of Building Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Reactive mass transport in concrete including for gaseous constituents using a two-phase moisture transport approach2020In: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 232, p. 1-14, article id 117148Article in journal (Refereed)
    Abstract [en]

    This article presents the further development of a tool for multi-phase reactive mass transport modelingfor durability estimation of cement-based materials, by the addition of the gas phase, adopting a trulyseparate two-phase moisture transport approach. The governing system of equations are based on phys-ically sound hybrid mixture based version of the Poisson-Nernst-Planck system of equations includinggaseous transport in the air-filled space, ionic transport in the liquid phase, electro-migration of ionicspecies, a two-phase moisture transport model, and sorption. The addition of the gas phase and thetwo-phase moisture description enables the user of the model to investigate individual and combinedeffects of different degradation processes in unsaturated systems. The altering of hydrated cement underthree different environments were studied representing an accelerated carbonation environment, a sub-merged marine environment and a cyclic drying-wetting zone in a marine environment, to illustratesome of the model’s capabilities.

  • 4.
    Adler, Anna
    et al.
    Uppsala University, Sweden.
    Inoue, Yuuki
    Univ Tokyo, Japan.
    Sato, Yuya
    Univ Tokyo, Japan.
    Ishihara, Kazuhiko
    Univ Tokyo, Japan.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Uppsala University, Sweden.
    Nilsson, Bo
    Uppsala University, Sweden.
    Teramura, Yuji
    Uppsala University, Sweden;Univ Tokyo, Japan;Natl Inst Adv Ind Sci & Technol, Japan.
    Synthesis of poly(2-methacryloyloxyethyl phosphorylcholine)-conjugated lipids and their characterization and surface properties of modified liposomes for protein interactions2021In: Biomaterials Science, ISSN 2047-4830, E-ISSN 2047-4849, Vol. 9, no 17, p. 5854-5867Article in journal (Refereed)
    Abstract [en]

    Poly(ethylene glycol) (PEG) is frequently used for liposomal surface modification. However, as PEGylated liposomes are cleared rapidly from circulation upon repeated injections, substitutes of PEG are being sought. We focused on a water-soluble polymer composed of 2-methacryloyloxyethyl phosphorylcholine (MPC) units, and synthesized poly(MPC) (PMPC)-conjugated lipid (PMPC-lipid) with degrees of MPC polymerization ranging from 10 to 100 (calculated molecular weight: 3 to 30 kDa). In addition, lipids with three different alkyl chains, myristoyl, palmitoyl, and stearoyl, were applied for liposomal surface coating. We studied the interactions of PMPC-lipids with plasma albumin, human complement protein C3 and fibrinogen using a quartz crystal microbalance with energy dissipation, and found that adsorption of albumin, C3 and fibrinogen could be suppressed by coating with PMPC-lipids. In particular, the effect was more pronounced for PMPC chains with higher molecular weight. We evaluated the size, polydispersity index, surface charge, and membrane fluidity of the PMPC-lipid-modified liposomes. We found that the effect of the coating on the dispersion stability was maintained over a long period (98 days). Furthermore, we also demonstrated that the anti-PEG antibody did not interact with PMPC-lipids. Thus, our findings suggest that PMPC-lipids can be used for liposomal coating.

  • 5.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Adamopoulos, Stergios
    Swedish university of agricultural sciences, Sweden.
    Li, Junqiu
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kovacikova, Janka
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering.
    Prediction of mechanical performance of acetylated MDF at different humid conditions2020In: Applied Sciences, E-ISSN 2076-3417, Vol. 10, no 23, p. 1-16, article id 8712Article in journal (Refereed)
    Abstract [en]

    Change of relative humidity (RH) in surrounding environment can greatly affect the physical and mechanical properties of wood-based panels. Commercially produced acetylated medium density fiberboard (MDF), Medite Tricoya®, was used in this study to predict strength and stiffness under varying humid conditions by separating samples in parallel (//) and perpendicular (⊥) to the sanding directions. Thickness swelling, static moduli of elasticity (MOEstat) and rupture (MORstat), and internal bond (IB) strength were measured at three different humid conditions, i.e., dry (35% RH), standard (65% RH) and wet (85% RH). Internal bond (IB) strength was also measured after accelerated aging test. A resonance method was used to determine dynamic modulus of elasticity (MOEdyn) at the aforementioned humid conditions. Linear regression and finite element (FE) analyses were used to predict the MDF’s static bending behavior. Results showed that dimensional stability, MOEstat, MORstat and IB strength decreased significantly with an increase in RH. No reduction of IB strength was observed after 426 h of accelerated aging test. A multiple regression model was established using MOEdyn and RH values to predict MOEstat and MORstat. In both directions (// and ⊥), highly significant relationships were observed. The predicted and the measured values of MOEstat and MORstat were satisfactorily related to each other, which indicated that the developed model can be effectively used for evaluating the strength and stiffness of Medite Tricoya® MDF samples at any humid condition. Percent errors of two different simulation techniques (standard and extended FE method) showed highly efficient way of simulating the MDF structures with low fidelity.

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  • 6.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Poggi, Francesco
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Walther, Thomas
    IKEA Industry AB, Sweden.
    Resonance and time-of-flight methods for evaluating the modulus of elasticity of particleboards at different humid conditions2020In: Wood research, ISSN 1336-4561, Vol. 65, no 3, p. 365-380Article in journal (Refereed)
    Abstract [en]

    Non-destructive testing of wood panels by either resonance or time-of-flight (TOF) methods provides possibilities for predicting their static bending properties. In the present study, three non-destructive devices (BING - Beam Identification by Non-destructive Grading by CIRAD, Montpellier, France, Fakopp Ultrasonic Timer and Sylvatest TRIO) were used for measuring the dynamic stiffness of different particleboard types. Fakopp Ultrasonic Timer and Sylvatest TRIO produce ultrasonic pulses to measure the sound velocity while BING uses resonance frequencies. Commercially produced particleboards with different thickness and densities were used to measure the dynamic modulus of elasticity (MOEdyn) in two directions (parallel and perpendicular to the production line) and at three different humidity levels (dry - 35%, standard - 65% and wet - 85% RH in constant temperature of 20°C ). MOEdyn of particleboards were correlated with the static moduli of elasticity (MOEstat) and rupture (MORstat). It was found that the non-destructive methods gave higher MOEdyn values in both production directions than that of MOEstat values. MOEdyn was found to decrease from dry to wet conditions. A very strong and statistically significant correlation existed between MOEdyn and static bending properties. MOEdyn correlated stronger to MOEstat than MORstat. At different humidity level, all three methods- Fakopp Ultrasonic Timer, BING and Sylvatest TRIO analyses showed good predicting capabilities to estimate MOEstat and MORstat of different particleboard types with high level of accuracy.

  • 7.
    Ahmed, Sheikh Ali
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, The University Administration.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Green Sustainable Development.
    Brischke, Christian
    University of Goettingen, Germany.
    Adamopoulos, Stergios
    Swedish University of Agricultural Sciences, Sweden.
    Anatomical, Physical, Chemical, and Biological Durability Properties of Two Rattan Species of Different Diameter Classes2022In: Forests, E-ISSN 1999-4907, Vol. 13, no 1, article id 132Article in journal (Refereed)
    Abstract [en]

    Rattan cane is an important forest product with economic value. Its anatomical, physical, and biological properties vary with the cane height. This makes it difficult to select the appropriate cane diameter for harvesting. Understanding the material properties of rattan cane with different diameter sizes is important to enhance its utilization and performance for different end uses. Thus, the present study was performed on two rattan species, Calamus zollingeri and Calamus ornatus, at two different cane heights (bottom/mature and top/juvenile). Calamus zollingeri was studied at diameter classes of 20 mm and 30 mm, while Calamus ornatus was analyzed at a diameter class of 15 mm. The anatomical properties, basic density, volumetric swelling, dynamic moisture sorption, and biological durability of rattan samples were studied. The results showed that C. zollingeri with a 20 mm diameter exhibited the highest basic density, hydrophobicity, dimensional stability, and durability against mold and white-rot (Trametes versicolor) fungi. As confirmed by anatomical studies, this could be due to the higher vascular bundle frequency and longer thick-walled fibers that led to a denser structure than in the other categories. In addition, the lignin content might have a positive effect on the mass loss of different rattan canes caused by white-rot decay.

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  • 8.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Elastic Properties and Hardness of Mixed Alkaline Earth Silicate Oxynitride Glasses2022In: Materials, E-ISSN 1996-1944, Vol. 15, no 14, article id 5022Article in journal (Refereed)
    Abstract [en]

    The incorporation of nitrogen as a second anion species into oxide glasses offers unique opportunities for modifying glass properties via changes in glass polymerization and structure. In this work, the compositional dependence of elastic properties and the nanoindentation hardness of mixed alkaline-earth silicate oxynitride glasses containing a high amount of nitrogen (>15 at.%, c.a. 35 e/o) were investigated. Three series of silicon oxynitride glass compositions AE-Ca-Si-O-N glasses (where AE = Mg, Sr, and Ba) having varying amounts of modifiers were prepared using a new glass synthesis route, in which a precursor powder of metal hydrides was used. The obtained glasses contained high amounts of N (19 at.%, c.a. 43 e/o) and modifier cations (26 at.%, c.a. 39 e/o). Mg-Ca-Si-O-N glasses had high values of nanohardness (12-16 GPa), along with a reduced elastic modulus (130-153 GPa) and Young's modulus (127-146 GPa), in comparison with the Sr-Ca- and Ba-Ca-bearing oxynitride glasses. Both the elastic modulus and the nanohardness of AE-Ca-Si-O-N glasses decreased with an increase in the atomic number of the AE element. These property changes followed a linear dependence on the effective cation field strength (ECFS) of the alkaline earth (AE) modifier, according to their valences and ionic radii. No mixed alkaline-earth effect was observed in the current investigation, indicating that the properties were more dictated by the nitrogen content.

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  • 9.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Impact of the Atomic Packing Density on the Properties of Nitrogen-Rich Calcium Silicate Oxynitride Glasses2022In: Materials, E-ISSN 1996-1944, Vol. 15, no 17, article id 6054Article in journal (Refereed)
    Abstract [en]

    In this work, the impact of the atomic packing density/fractional glass compactness of Ca-Si-O-N glasses on glass transition and crystallization temperatures, glass density, microhardness, molar volume, and refractive index were examined. It was found that the atomic packing density increased with increasing the nitrogen content and decreased with increasing the Ca content in the glass network. Furthermore, density, glass transition and crystallization temperatures, and refractive index, increased with an increasing atomic packing density of the glass, while molar volume increased with decreasing atomic packing density values. The change in hardness with atomic packing density is less clear and suggests that the atomic packing density does not solely control the underlying deformation mechanism. There is indeed competition between densification (favored at low packing density values) and isochoric shear (at larger packing density). Despite that, the effects of nitrogen as a network former and Ca as a modifier are significantly independent. The obtained results indicate that the atomic packing density of the prepared samples linearly depends on many mechanical and optical properties, suggesting that the glass network and cross-linking are proportional to the ionic radius of the Ca and the nitrogen content, respectively.

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  • 10.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Novel thin films in the M-Si-O-N systems2019In: Presented at the Fourth International Conference on Nanomaterials: Synthesis, Characterization and Applications (ICN 2019). 12-14 April 2019, Kerala, India, 2019, p. 7-7Conference paper (Refereed)
  • 11.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Ellison, Adam
    Glass Science and Technology Corning Incorporated, USA.
    Luo, Jian
    Glass Science and Technology Corning Incorporated, USA.
    Edén, Mattias
    Stockholm University, Sweden.
    Composition–structure–property relationships of transparent Ca–Al–Si–O–N oxynitride glasses: The roles of nitrogen and aluminum2023In: Journal of The American Ceramic Society, ISSN 0002-7820, E-ISSN 1551-2916, Vol. 106, no 3, p. 1748-1765Article in journal (Refereed)
    Abstract [en]

    We explore the formation and composition–structure–property correlations of transparent Ca–Al–Si–O–N glasses, which were prepared by a standard melt-quenching technique using AlN as the nitrogen source and incorporating up to 8 at.% of N. Their measured physical properties of density, molar volume, compactness, refractive index, and hardness—along with the Young, shear, and bulk elastic moduli—depended roughly linearly on the N content. These effects are attributed primarily to the improved glass-network cross-linking from N compared to O, rather than the formation of higher-coordination AlO5 and AlO6 groups, where 27Al magic-angle-spinning nuclear magnetic resonance experimentation revealed that aluminum is predominately present in tetrahedral coordination as AlO4 units. Yet, several physical properties, such as the refractive index along with the bulk, shear, and Young's elastic moduli, increase concomitantly with the Al content of the glass. We discuss the incompletely understood mechanical–property boosting role of Al as observed both herein and in previous reports on oxynitride glasses, moreover suggesting glass-composition domains that are likely to offer optimal mechanical properties. 

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  • 12.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Hakeem, Abbas Saeed
    King Fahd Univ Petr & Minerals, Saudi Arabia.
    Eriksson, Mirva
    Stockholm University, Sweden.
    Wójcik, Natalia A.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Gdansk Univ Technol, Poland.
    A novel approach for processing CaAlSiON glass-ceramics by spark plasma sintering: Mechanical and electrical properties2022In: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 42, no 1, p. 96-104Article in journal (Refereed)
    Abstract [en]

    Lithium containing glassy materials can be used as solid electrolytes or electrode materials for lithium-ion batteries due to their high energy density. Conventional melt-quenched Ca11Al14Si16O49N10 glass powder containing 24 e/o N, doped with Li-ions (1, 3, and 6 wt. %) and sintered by spark plasma sintering technique (SPS) was studied. The benefits of using SPS to produce glass-ceramics are rapid heating rates compared to conventional consolidation techniques and tuning of properties, adjusting the temperature, holding time (closed to Tg temperature), heating rate (solidification), and pressure (densification) profile during the heat treatment using SPS. Pure glass and glass-ceramic were obtained under identical SPS conditions and compared with pristine oxynitride and soda-lime-silicate (float) glasses. XRD and SEM analysis confirmed that increasing the amount of Li increases the crystallinity in the glass matrix. Nano-indentation analysis showed a decreased hardness and reduced elastic modulus values with the addition of Li-ions. The direct current conductivity increases with the addition of Li due to the high mobility of Li-ions. However, the float glass sample doped with 6 wt.% of Li exhibits even higher values of D.C. conductivity, than the analogously doped Ca11Al14Si16O49N10 glass. The magnitude of activation energy (more than 1 eV) is typical for an ion hopping mechanism and the D.C. conduction mechanism is dominated by Li+ hopping.

  • 13.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Paul, Biplab
    Linköping University, Sweden.
    Magnusson, Roger
    Linköping University, Sweden.
    Erik, Ekström
    Linköping University, Sweden.
    Pallier, Camille
    Linköping University, Sweden.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Eklund, Per
    Linköping University, Sweden.
    Birch, Jens
    Linköping University, Sweden.
    Optical and mechanical properties of amorphous Mg-Si-O-N thin films deposited by reactive magnetron sputtering2019In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 372, no 25, p. 9-15Article in journal (Refereed)
    Abstract [en]

    In this work, amorphous thin films in Mg-Si-O-N system typically containing >15 at.% Mg and 35 at.% N were prepared in order to investigate especially the dependence of optical and mechanical properties on Mg composition. Reactive RF magnetron co-sputtering from magnesium and silicon targets were used for the deposition of Mg-Si-O-N thin films. Films were deposited on float glass, silica wafers and sapphire substrates in an Ar, N2 and O2 gas mixture. X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, spectroscopic ellipsometry, and nanoindentation were employed to characterize the composition, surface morphology, and properties of the films. The films consist of N and Mg contents up to 40 at.% and 28 at.%, respectively and have good adhesion to substrates and are chemically inert. The thickness and roughness of the films increased with increasing content of Mg. Both hardness (16–21 GPa) and reduced elastic modulus (120–176 GPa) are strongly correlated with the amount of Mg content. The refractive index up to 2.01 and extinction coefficient up to 0.18 were found to increase with Mg content. The optical band gap (3.1–4.3) decreases with increasing the Mg content. Thin film deposited at substrate temperature of 100 °C shows a lower value of hardness (10 GPa), refractive index (1.75), and higher values of reduced elastic modulus (124 GPa) as compared to the thin film deposited at 310 °C and 510 °C respectively, under identical synthesis parameters.

  • 14.
    Ali, Sharafat
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Wójcik, Natalia A.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Gdańsk University of Technology, Poland.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Kamitsos, Efstratios
    Theoretical and Physical Chemistry Institute, Greece.
    Li, Xinghua
    Corning Incorporated, USA.
    Luo, Jian
    Corning Incorporated, USA.
    Möncke, Doris
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Alfred University, USA.
    Synthesis, structural characterization, and thermal properties of Ca- and La-doped soda-lime glasses by laser melting2020In: International Journal of Applied Glass Science, Vol. 11, no 4, p. 699-706Article in journal (Refereed)
    Abstract [en]

    Laser melting techniques have been used in the preparation of unconventional glasscompositions with high melting temperatures. Thus, we wanted to test the feasibilityof using a CO2 laser in the preparation of nitrogen-rich oxynitride glasses and nitridesilicate glasses. Melting from oxides and metallic raw materials, we wanted to studyfirst glass formation and possible evaporation losses of the glass components. Twoglass series were prepared and studied for their structure and thermal properties, onewith Ca2+- and a higher melting La3+-doped soda-lime-silicate (SLS) series. In lessthan 3 minutes of laser melting, spheres of up to 6 mm diameter were successfullyfabricated. The obtained glass samples were homogeneous and transparent in thevisible region. X-ray diffraction and Raman spectroscopic analysis confirmed theamorphous nature of the synthesized samples. Sodium losses increase as calcium isadded to the soda-lime-silicate glass. As expected, increasing Ca2+ or La3+ additionlead to increased depolymerization of the silicate network. Moreover, the increasesin Tg with the addition of Ca2+ or La3+ ions indicating strengthening of the sodalime-silicate glass by increasing strength of the M-O bonds of divalent and trivalentions over monovalent sodium ions, weak Na-O bonds also resulting in significantevaporation loss during the short laser melting times. The thermal stability decreasesupon addition of Ca2+ or La3+ ions to the soda-lime-silicate glasses.

  • 15.
    Anaspure, Prasad
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Suriyanarayanan, Subramanian
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Nicholls, Ian A.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Palladium nanoparticles immobilized on polyethylenimine-derivatized gold surfaces for catalysis of Suzuki reactions: development and application in a lab-on-a-chip context2021In: RSC Advances, E-ISSN 2046-2069, Vol. 11, no 56, p. 35161-35164Article in journal (Refereed)
    Abstract [en]

    Gold surface-bound hyperbranched polyethyleneimine (PEI) films decorated with palladium nanoparticles have been used as efficient catalysts for a series of Suzuki reactions. This thin film-format demonstrated good catalytic efficiency (TON up to 3.4 x 10(3)) and stability. Incorporation into a quartz crystal microbalance (QCM) instrument illustrated the potential for using this approach in lab-on-a-chip-based synthesis applications.

  • 16.
    Anuar Bahari, Shahril
    et al.
    Universiti Teknologi MARA (UiTM), Malaysia.
    Nazarudin Zakaria, Mohd
    Universiti Teknologi MARA (UiTM), Malaysia.
    Osman, Syaiful
    Universiti Teknologi MARA (UiTM), Malaysia.
    Abu, Falah
    Universiti Teknologi MARA (UiTM), Malaysia.
    Jani Saad, Mohamad
    Malaysian Agricultural Research and Development Institute (MARDI), Malaysia.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Green Sustainable Development.
    Strength Performance and Microstructure Characteristic of Naturally-Bonded Fiberboard Composite from Malaysian Bamboo (Bambusa vulgaris)2022In: Journal of Renewable Materials, ISSN 2164-6325, E-ISSN 2164-6341, Vol. 10, no 10, p. 2581-2591Article in journal (Refereed)
    Abstract [en]

    This study investigated the mechanical properties and microstructural characteristics of fiberboard composite produced by naturally-bonded Malaysian bamboo fiber (Bambusa vulgaris). The components that obtained through soda pulping of bamboo culms such as fiber and black liquor, were used for the preparation of high-density fibreboard composite at two target densities of 850 and 950 kg/m3. The bamboo fiberboard composite (BFC) were then produced at 200°C and two pressing parameters of 125 and 175 s/mm. The mechanical properties, e.g., flexural strength and internal bonding (IB) of BFC samples were evaluated according to BS EN 310: 1993 and BS EN 319: 1993, respectively. It was found that the mechanical performance of the composite with 850 kg/m3 density was significantly higher than 950 kg/m3 ones, especially for the samples with 125 s/mm pressing parameter. Microstructure characteristic of the BFC samples illustrated that the fiber linkages were cracked in the composites with higher density, e.g., the composite with the density of 950 kg/m3 and also black liquor were slightly degraded at longer pressing time, which led to the reduction in mechanical properties, especially in IB strength.

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  • 17.
    Asawa, Kenta
    et al.
    Univ Tokyo, Japan.
    Ishihara, Kazuhiko
    Univ Tokyo, Japan.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Uppsala University, Sweden.
    Nilsson, Bo
    Uppsala University, Sweden.
    Teramura, Yuji
    Univ Tokyo, Japan;Uppsala University, Sweden.
    Cell Surface Functionalization with Heparin-Conjugated Lipid to Suppress Blood Activation2021In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 31, no 11, article id 2008167Article in journal (Refereed)
    Abstract [en]

    Organ transplantation leads to damage of the endothelial glycocalyx of the transplanted organ, and the activated endothelial surface induces thromboinflammation. The result is dysfunction of the transplanted organ, known as ischemia reperfusion injury (IRI). Long-term graft survival strongly depends on the regulation of IRI. Here the aim is to reconstruct the glycocalyx to regulate blood activation during IRI. Heparin-conjugated lipid (fHep-lipid) is synthesized with 0.6, 1.8, 2.7, 4.5, or 8.0 fragmented heparins per lipid to compare their anticoagulation activity. First, liposome and cells are modified with each fHep-lipid and the surface properties are evaluated. Then the hemocompatibility of the modified human mesenchymal stem cells (hMSCs) is examined in a loop model using human blood. The antithrombin-binding capacity and anti-factor Xa activity of the fHep-lipids depend on the number of conjugated heparins, with efficacy increasing with increasing number of heparins. The modified liposomes are highly negatively charged and show strong anti-factor Xa activity. In addition, the cell surfaces of human erythrocytes and hMSCs can be uniformly modified with fHep-lipid. The whole blood studies reveal that fHep-lipid on hMSCs can prevent generation of thrombin-antithrombin complexes, coagulation markers, and platelet aggregation, whereas unmodified hMSCs trigger activation of the platelet and coagulation systems.

  • 18.
    Asif, Sana
    et al.
    Uppsala University, Sweden.
    Asawa, Kenta
    Univ Tokyo, Japan.
    Inoue, Yuuki
    Univ Tokyo, Japan.
    Ishihara, Kazuhiko
    Univ Tokyo, Japan.
    Lindell, Björn
    Uppsala University, Sweden.
    Holmgren, Robin
    Uppsala University, Sweden.
    Nilsson, Bo
    Uppsala University, Sweden.
    Ryden, Anneli
    Swedish University of Agricultural Sciences, Sweden.
    Jensen-Waern, Marianne
    Swedish University of Agricultural Sciences, Sweden.
    Teramura, Yuji
    Uppsala University, Sweden;Univ Tokyo, Japan.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Uppsala University, Sweden.
    Validation of an MPC Polymer Coating to Attenuate Surface-Induced Crosstalk between the Complement and Coagulation Systems in Whole Blood in In Vitro and In Vivo Models2019In: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 19, no 5, article id 1800485Article in journal (Refereed)
    Abstract [en]

    Artificial surfaces that come into contact with blood induce an immediate activation of the cascade systems of the blood, leading to a thrombotic and/or inflammatory response that can eventually cause damage to the biomaterial or the patient, or to both. Heparin coating has been used to improve hemocompatibility, and another approach is 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymer coatings. Here, the aim is to evaluate the hemocompatibility of MPC polymer coating by studying the interactions with coagulation and complement systems using human blood in vitro model and pig in vivo model. The stability of the coatings is investigated in vitro and MPC polymer-coated catheters are tested in vivo by insertion into the external jugular vein of pigs to monitor the catheters' antithrombotic properties. There is no significant activation of platelets or of the coagulation and complement systems in the MPC polymer-coated one, which was superior in hemocompatibility to non-coated matrix surfaces. The protective effect of the MPC polymer coat does not decline after incubation in human plasma for up to 2 weeks. With MPC polymer-coated catheters, it is possible to easily draw blood from pig for 4 days in contrast to the case for non-coated catheters, in which substantial clotting is seen.

  • 19.
    Azuma, Tomoyuki
    et al.
    Univ Tokyo, Japan.
    Matsushita, Taishi
    Univ Tokyo, Japan.
    Manivel, Vivek Anand
    Uppsala University, Sweden.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Uppsala University, Sweden.
    Nilsson, Bo
    Uppsala University, Sweden.
    Teramura, Yuji
    Univ Tokyo, Japan;Uppsala University, Sweden.
    Takai, Madoka
    Univ Tokyo, Japan.
    Poly(2-aminoethyl methacrylate)-based polyampholyte brush surface with carboxylic groups to improve blood compatibility2020In: Journal of Biomaterials Science. Polymer Edition, ISSN 0920-5063, E-ISSN 1568-5624, Vol. 31, no 5, p. 679-693Article in journal (Refereed)
    Abstract [en]

    Zwitterionic material-based polymer brush significantly prevents protein adsorption and cell adhesion, which leads to the blood compatibility. However, zwitterionic polymer itself is difficult to be modified further, for the blood compatibility since the charged balance is impaired after the modification. In this research, chemically modifiable mixed charge polymer brush is designed, without impairing its characteristics. Condensed mixed charge polymer brush will work like zwitterionic material because neighbouring opposite charge is reported to be important in the zwitterionic material. Cationic polymer brush with primary amine group, which is based on 2-aminoethyl methacrylate (AEMA), was prepared and modified by succinic anhydride to obtain carboxylic group induced poly(AEMA). The ratio of primary amine group and carboxylic group was optimized to obtain the polyampholyte brush. The blood compatibility was evaluated by measuring coagulation/complement activation, protein adsorption and cell adhesion induced by the polymer. Our designed cationic-based polyampholyte brush prevented coagulation/complement activation comparable to poly(2-methacryloyloxyethyl phosphorylcholine) brush, based on intra-monomer interaction, because condensed mix charge works like zwitterion.

  • 20.
    Bobadilha, Gabrielly S.
    et al.
    Mississippi State University, USA.
    Stokes, C. Elizabeth
    Mississippi State University, USA.
    Kirker, Grant
    U.S. Forest Products Laboratory, USA.
    Ahmed, Sheikh Ali
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Ohno, Katie
    U.S. Forest Products Laboratory, USA.
    Lopes, Dercilio Junior Verly
    Mississippi State University, USA.
    Effect of exterior wood coatings on the durability of cross-laminated timber against mold and decay fungi2020In: BioResources, E-ISSN 1930-2126, Vol. 15, no 4, p. 8420-8433Article in journal (Refereed)
    Abstract [en]

    Cross-laminated timber (CLT) is increasingly used in building construction worldwide. Durability of CLT against fungal attack has yet to be fully explored. Water intrusion in mass timber can yield dimensional changes and microbial growth. This study evaluated the performance of CLT coated with various water- and solvent-based stains commercially available in the United States. Twelve coatings were tested for moisture excluding effectiveness, water repellency effectiveness, volumetric swelling, and anti-swelling efficiency. Only five coatings repelled water, limiting dimensional changes. A modified version of AWPA E10-16 (2016) was performed to evaluate decay of the coated CLT samples. Weight losses were recorded after 18 weeks' exposure to the brown-rot decay fungus Gloeophyllum trabeum. In accelerated mold testing, coated CLT samples were grown in chambers containing spores of Aspergillus sp., Rhizopus sp., and Penicillium sp. for 29 d and assessed visually for mold growth. In both tests, coating C (transparent, water-based, alkyd/acrylic resin) performed the best among the tested coatings. Mold growth was completely prevented, and weight loss caused by G. trabeum was approximately 1.33%. Although coating C prevented decay for 18 weeks, coatings are not intended to protect against decay fungi. However, they may offer short-term protection during transport, storage, and construction. 

  • 21.
    Bolarinwa, Sherifdeen O.
    et al.
    King Abdulaziz Univ, Saudi Arabia.
    Sattar, Shahid
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    AlShaikhi, Abdullah A.
    King Abdulaziz Univ, Saudi Arabia.
    Superior gas sensing properties of beta-In2Se3: A first-principles investigation2022In: Computational materials science, ISSN 0927-0256, E-ISSN 1879-0801, Vol. 201, article id 110880Article in journal (Refereed)
    Abstract [en]

    Using first-principles calculations, we report structural and electronic properties of CO, NO2 and NO molecular adsorption on beta-In2Se3 in comparison to a previous study on a-phase. Analysis and comparison of adsorption energies and extent of charge transfer indicates beta-In2Se3 to be selective in detecting gas molecules. We found NO molecules acting as charge donor whereas CO and NO2 molecules as charge acceptors, respectively, experiencing physisorption in all cases. Owing to enhanced adsorption, faster desorption and improved selectivity of the gas molecules discussed in detail, we conclude beta-In2Se3 to be a superior gas sensing material ideal for chemoresistive-type gas sensing applications.

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  • 22.
    Boventi, Matteo
    et al.
    Univ Milano Bicocca, Italy.
    Mauri, Michele
    Univ Milano Bicocca, Italy.
    Golker, Kerstin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Wiklander, Jesper G.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Nicholls, Ian A.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Simonutti, Roberto
    Univ Milano Bicocca, Italy.
    Porosity of Molecularly Imprinted Polymers Investigated by 129Xe NMR Spectroscopy2022In: ACS Applied Polymer Materials, E-ISSN 2637-6105, Vol. 4, no 12, p. 8740-8749Article in journal (Refereed)
    Abstract [en]

    Molecularly imprinted polymers (MIPs) display intriguing recognition properties and can be used as sensor recognition elements or in separation. In this work, we investigated the formation of hierarchical porosity of compositionally varied MIPs using 129Xe Nuclear Magnetic Resonance (NMR) and 1H Time Domain Nuclear Magnetic Resonance (TD-NMR). Variable temperature 129Xe NMR established the morphological variation with respect to the degree of cross-linking, supported by 1H TDNMR determination of polymer chain mobility. Together, the results indicate that a high degree of cross-linking stabilizes the porous structure: highly cross-linked samples display a significant amount of accessible mesopores that instead collapse in less structured polymers. No significant differences can be detected due to the presence of templated pores in molecularly imprinted polymers: in the dry state, these specific shapes are too small to accommodate xenon atoms, which, instead, probe higher levels in the porous structure, allowing their study in detail. Additional resonances at a high chemical shift are detected in the 129Xe NMR spectra. Even though their chemical shifts are compatible with xenon dissolved in bulk polymers, variable temperature experiments rule out this possibility. The combination of 129Xe and TDNMR data allows attribution of these resonances to softer superficial regions probed by xenon in the NMR time scale. This can contribute to the understanding of the surface dynamics of polymers.

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  • 23.
    Brandwijk, Ricardo J. M. G. E.
    et al.
    Hycult Biotechnol bv, Netherlands.
    Michels, Marloes A. H. M.
    Radboud Univ Nijmegen Med Ctr, Netherlands.
    van Rossum, Mara
    Hycult Biotechnol bv, Netherlands.
    de Nooijer, Aline H.
    Radboud Univ Nijmegen Med Ctr, Netherlands.
    Nilsson, Per H.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Univ Oslo, Norway;Oslo University Hospital Rikshospitalet, Norway.
    de Bruin, Wieke C. C.
    Hycult Biotechnol bv, Netherlands.
    Toonen, Erik J. M.
    Hycult Biotechnol bv, Netherlands.
    Pitfalls in complement analysis: A systematic literature review of assessing complement activation2022In: Frontiers in Immunology, E-ISSN 1664-3224, Vol. 13, article id 1007102Article in journal (Refereed)
    Abstract [en]

    Background: The complement system is an essential component of our innate defense and plays a vital role in the pathogenesis of many diseases. Assessment of complement activation is critical in monitoring both disease progression and response to therapy. Complement analysis requires accurate and standardized sampling and assay procedures, which has proven to be challenging. Objective: We performed a systematic analysis of the current methods used to assess complement components and reviewed whether the identified studies performed their complement measurements according to the recommended practice regarding pre-analytical sample handling and assay technique. Results are supplemented with own data regarding the assessment of key complement biomarkers to illustrate the importance of accurate sampling and measuring of complement components. Methods: A literature search using the Pubmed/MEDLINE database was performed focusing on studies measuring the key complement components C3, C5 and/or their split products and/or the soluble variant of the terminal C5b-9 complement complex (sTCC) in human blood samples that were published between February 2017 and February 2022. The identified studies were reviewed whether they had used the correct sample type and techniques for their analyses. Results: A total of 92 out of 376 studies were selected for full-text analysis. Forty-five studies (49%) were identified as using the correct sample type and techniques for their complement analyses, while 25 studies (27%) did not use the correct sample type or technique. For 22 studies (24%), it was not specified which sample type was used. Conclusion: A substantial part of the reviewed studies did not use the appropriate sample type for assessing complement activation or did not mention which sample type was used. This deviation from the standardized procedure can lead to misinterpretation of complement biomarker levels and hampers proper comparison of complement measurements between studies. Therefore, this study underlines the necessity of general guidelines for accurate and standardized complement analysis

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  • 24.
    Dugic, Izudin
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Effect of Casting Temperature on the Surface Finish of Grey Iron Castings2019In: Materials Processing Fundamentals 2019 / [ed] Lambotte G., Lee J., Allanore A., Wagstaff S., Springer, 2019, p. 87-95Conference paper (Refereed)
    Abstract [en]

    One of the most common surface defects in sand casting of grey cast iron is caused by metal penetration into the sand mould. Metal penetration is a surface condition in which metal or metal oxides have filled the voids between sand grains to various depth without displacing them, thus yielding a phase of sand grains surrounded by metal and frequently by mould–metal reaction products. The penetration is often so severe that casting components are beyond the point of economical rework and must be scrapped. This experimental work has focused on reducing metal penetration on casting component on a production scale. The casting component produced has strongly affected by sand sintering metal penetration. A series of simulations were performed with the casting simulation program MagmaSoft® in order to investigate the solidification characteristics as well as the porosity formation in the casting component. 

  • 25.
    Dugic, Izudin
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    How to Prevent Gas Porosity Defects in Castings of Stator Housing in Grey Cast Iron2020In: TMS 2020 149th Annual Meeting & Exhibition Supplemental Proceedings / [ed] Peng Z.,Hwang J.-Y.,Downey J.,Gregurek D.,Zhao B.,Yucel O.,Keskinkilic E.,Jiang T.,White J.,Mahmoud M., Springer, 2020, p. 1139-1148Conference paper (Refereed)
    Abstract [en]

    Grey cast iron is one of the easiest metals to cast in a foundry, and of ferrous metals, it has the lowest pouring temperature, high fluidity, and very low shrinkage during the transformation from the liquid to solid phase. One of the disadvantages of this grade of cast iron is the presence of the different types of defects produced in green sand casting. Cast defects are, at a higher proportion, caused by evolution of gases. Pinholes and blowholes are major casting defects caused by gases. This experimental work has focused on reducing gas defects on casting component, stator housing, at a production scale using the green sand casting process. The casting component produced was strongly affected by gas defects. A series of simulations were performed using the casting simulation program MAGMASOFT® in order to investigate the solidification characteristics as well as the porosity formation in the casting component.

  • 26.
    Dugic, Izudin
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Microscopic investigation of test specimen 2 after thermal shock test2022Report (Other academic)
    Abstract [en]

    Microscopic investigation

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  • 27.
    Dugic, Izudin
    Linnaeus University, Faculty of Technology, Department of Mechanical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Microscopic investigation of the test specimen after the thermal shock test2021Report (Other (popular science, discussion, etc.))
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  • 28.
    Eriksson, Oskar
    et al.
    Uppsala University, Sweden.
    Mohlin, Camilla
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Nilsson, Bo
    Uppsala University, Sweden.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Uppsala University, Sweden.
    The Human Platelet as an Innate Immune Cell: Interactions Between Activated Platelets and the Complement System2019In: Frontiers in Immunology, E-ISSN 1664-3224, Vol. 10, p. 1-16, article id 1590Article, review/survey (Refereed)
    Abstract [en]

    Platelets play an essential role in maintaining homeostasis in the circulatory system after an injury by forming a platelet thrombus, but they also occupy a central node in the intravascular innate immune system. This concept is supported by their extensive interactions with immune cells and the cascade systems of the blood. In this review we discuss the close relationship between platelets and the complement system and the role of these interactions during thromboinflammation. Platelets are protected from complement-mediated damage by soluble and membrane-expressed complement regulators, but they bind several complement components on their surfaces and trigger complement activation in the fluid phase. Furthermore, localized complement activation may enhance the procoagulant responses of platelets through the generation of procoagulant microparticles by insertion of sublytic amounts of C5b9 into the platelet membrane. We also highlight the role of post-translational protein modifications in regulating the complement system and the critical role of platelets in driving these reactions. In particular, modification of disulfide bonds by thiol isomerases and protein phosphorylation by extracellular kinases have emerged as important mechanisms to fine-tune complement activity in the platelet microenvironment. Lastly, we describe disorders with perturbed complement activation where part of the clinical presentation includes uncontrolled platelet activation that results in thrombocytopenia, and illustrate how complement-targeting drugs are alleviating the prothrombotic phenotype in these patients. Based on these clinical observations, we discuss the role of limited complement activation in enhancing platelet activation and consider how these drugs may provide opportunities for further dissecting the complex interactions between complement and platelets.

  • 29.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Water.
    Preferential Binding of Lanthanides to Methanol Dehydrogenase Evaluated with Density Functional Theory2021In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 125, no 9, p. 2251-2257Article in journal (Refereed)
    Abstract [en]

    Methanol dehydrogenase (MDH) is an enzyme used by certain bacteria for the oxidation of methanol to formaldehyde, which is a necessary metabolic reaction. The discovery of a lanthanide-dependent MDH reveals that lanthanide ions (Ln(3+)) have a role in biology. Two types of MDH exist in methane-utilizing bacteria: one that is Ca2+-dependent (MxaF) and another that is Ln(3+)-dependent. Given that the triply charged Ln(3+) are strongly hydrated, it is not clear how preference for Ln(3+) is manifested and if the Ca2+-dependent MxaF protein can also bind Ln(3+) ions. A computational approach was used to estimate the Gibbs energy differences between the binding of Ln(3+) and Ca2+ to MDH using density functional theory. The results show that both proteins bind La3+ with higher affinity than Ca2+, albeit with a more pronounced difference in the case of Ln(3+)-dependent MDH. Interestingly, the binding of heavier lanthanides is preferred over the binding of La3+, with Gd3+ showing the highest affinity for both proteins of all Ln(3+) ions that were tested (La3+, Sm3+, Gd3+, Dy3+, and Lu3+). Energy decomposition analysis reveals that the higher affinity of La3+ than Ca2+ to MDH is due to stronger contributions of electrostatics and polarization, which overcome the high cost of desolvating the ion.

  • 30.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Simulations of Biomolecules in Electrolyte Solutions2019In: Advanced Theory and Simulations, E-ISSN 2513-0390, Vol. 2, no 4, p. 1-10, article id 1800163Article in journal (Refereed)
    Abstract [en]

    Biomolecules including proteins, lipid membranes, and nucleic acids operate at an aqueous milieu that includes solvated ions. The interactions with ions affect biomolecules in different ways depending on the nature of the solute and the type of the ions. The dynamic nature of small soluble ions makes it difficult to follow them by structural methods. Consequently, theories were developed to explain how biomolecules interact in an environment that includes electrolytes. Moreover, simulations studies are often used to study such systems at the molecular or atomistic level. The status of the field, and inparticular of simulation studies, is the subject of this progress report.

  • 31.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Specific Ion and Concentration Effects in Acetate Solutions with Na+, K+ and Cs+2019In: ChemPhysChem, ISSN 1439-4235, E-ISSN 1439-7641, Vol. 20, no 8, p. 1006-1010Article in journal (Refereed)
    Abstract [en]

    How salt ions affect solutes and the water beyond the solvation shell is not well understood. Molecular dynamics simulations of alkali-acetate solutions were analysed here in order to examine if, and how, different cations and solute concentrations affect the water structure and the interactions between water and acetates. The results revealed that water structure is perturbed to more than 1 nm away from the acetates and that this effect is more pronounced in physiological than in molar electrolyte concentrations. Analysis of simulations of a soluble protein revealed that the water orientation is perturbed to at least 1.5 nm from the protein structure. Furthermore, modifications to the orientation of water around carboxylate side chains were shown to depend on the local environment on the protein surface, and could extend to well over 1 nm, which may have an effect on protein dynamics during MD simulations in small water boxes.

  • 32.
    Fromell, Karin
    et al.
    Uppsala university, Sweden.
    Adler, Anna
    Uppsala university, Sweden.
    Åman, Amanda
    Uppsala university, Sweden.
    Manivel, Vivek Anand
    Uppsala university, Sweden.
    Huang, Shan
    University of Gothenburg, Sweden.
    Duhrkop, Claudia
    Uppsala university, Sweden.
    Sandholm, Kerstin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Uppsala university, Sweden.
    Nilsson, Bo
    Uppsala university, Sweden.
    Assessment of the Role of C3(H2O) in the Alternative Pathway2020In: Frontiers in Immunology, E-ISSN 1664-3224, Vol. 11, p. 1-13, article id 530Article in journal (Refereed)
    Abstract [en]

    In this study we investigate the hydrolysis of C3 to C3(H2O) and its ability to initiate activation via the alternative pathway (AP) of the complement system. The internal thioester bond within C3 is hydrolyzed by water in plasma because of its inherent lability. This results in the formation of non-proteolytically activated C3(H2O) which is believed have C3b-like properties and be able to form an active initial fluid phase C3 convertase together with Factor B (FB). The generation of C3(H2O) occurs at a low but constant rate in blood, but the formation can be greatly accelerated by the interaction with various surfaces or nucleophilic and chaotropic agents. In order to more specifically elucidate the relevance of the C3(H2O) for AP activation, formation was induced in solution by repeated freeze/thawing, methylamine or KCSN treatment and named C3(x) where the x can be any of the reactive nucleophilic or chaotropic agents. Isolation and characterization of C3(x) showed that it exists in several forms with varying attributes, where some have more C3b-like properties and can be cleaved by Factor I in the presence of Factor H. However, in common for all these variants is that they are less active partners in initial formation of the AP convertase compared with the corresponding activity of C3b. These observations support the idea that formation of C3(x) in the fluid phase is not a strong initiator of the AP. It is rather likely that the AP mainly acts as an amplification mechanism of complement activation that is triggered by deposition of target-bound C3b molecules generated by other means.

  • 33.
    Gagner, Viktor Ahlberg
    et al.
    University of Gothenburg, Sweden.
    Lundholm, Ida
    University of Gothenburg, Sweden.
    Garcia-Bonete, Maria-Jose
    University of Gothenburg, Sweden.
    Rodilla, Helena
    Chalmers University of Technology, Sweden.
    Friedman, Ran
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Zhaunerchyk, Vitali
    University of Gothenburg, Sweden.
    Bourenkov, Gleb
    DESY, Germany.
    Schneider, Thomas
    DESY, Germany.
    Stake, Jan
    Chalmers University of Technology, Sweden.
    Katona, Gergely
    University of Gothenburg, Sweden.
    Clustering of atomic displacement parameters in bovine trypsin reveals a distributed lattice of atoms with shared chemical properties2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, p. 1-14, article id 19281Article in journal (Refereed)
    Abstract [en]

    Low-frequency vibrations are crucial for protein structure and function, but only a few experimental techniques can shine light on them. The main challenge when addressing protein dynamics in the terahertz domain is the ubiquitous water that exhibit strong absorption. In this paper, we observe the protein atoms directly using X-ray crystallography in bovine trypsin at 100 K while irradiating the crystals with 0.5THz radiation alternating on and off states. We observed that the anisotropy of atomic displacements increased upon terahertz irradiation. Atomic displacement similarities developed between chemically related atoms and between atoms of the catalytic machinery. This pattern likely arises from delocalized polar vibrational modes rather than delocalized elastic deformations or rigid-body displacements. The displacement correlation between these atoms were detected by a hierarchical clustering method, which can assist the analysis of other ultra-high resolution crystal structures. These experimental and analytical tools provide a detailed description of protein dynamics to complement the structural information from static diffraction experiments.

  • 34.
    García-Iruela, Alberto
    et al.
    Universidad Politécnica de Madrid, Spain.
    García Esteban, Luis
    Universidad Politécnica de Madrid, Spain.
    Garcia Fernández, Francisco
    Universidad Politécnica de Madrid, Spain.
    De Palacios, Paloma
    Universidad Politécnica de Madrid, Spain.
    Rodriguez-Navarro, Alejandro B
    Universidad de Granada, Spain.
    Gil Sánchez, Luis
    Universidad Politécnica de Madrid, Spain.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Effect of Degradation on Wood Hygroscopicity: The Case of a 400-Year-Old Coffin2020In: Forests, E-ISSN 1999-4907, Vol. 11, no 7, p. 1-15, article id 712Article in journal (Refereed)
    Abstract [en]

    The hygroscopicity and thermodynamic properties of Pinus sylvestris L. wood from a coffin allegedly holding the remains of famous Spanish author Miguel de Cervantes Saavedra (1547–1616) were studied using the 15 °C and 35 °C isotherms fitted to the Guggenheim–Anderson–de Boer model and comparing them with the isotherms of recently felled wood of the same species. In addition, using infrared spectroscopy (FTIR-ATR) and X-ray diffractograms, the functional groups were determined and the crystallinity and organization of the cell wall components were analyzed. The absence of the 1740 cm−1 group indicates hemicellulose degradation in the archaeological wood, and the X-ray diffractograms show a considerable decrease in cellulose crystallinity and disorganization of the cellulose crystallites. The greater availability of active –OH groups means that the archaeological wood isotherms are above the juvenile and mature wood isotherms, and therefore the thermodynamic balance in the sorption of the archaeological wood is greater.

  • 35.
    Gerogianni, Alexandra
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Dimitrov, Jordan D.
    Sorbonne Univ, France.
    Zarantonello, Alessandra
    Sorbonne Univ, France.
    Poillerat, Victoria
    Sorbonne Univ, France.
    Chonat, Satheesh
    Childrens Healthcare Atlanta, USA;Emory Univ, USA.
    Sandholm, Kerstin
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    McAdam, Karin E.
    Oslo Univ Hosp, Norway;Univ Oslo, Norway.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Uppsala University, Sweden.
    Mollnes, Tom E.
    Oslo Univ Hosp, Norway;Univ Oslo, Norway;Norwegian Univ Sci & Technol, Norway;Norwegian Univ Sci & Technol, Norway;Nordland Hosp, Norway.
    Mohlin, Camilla
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Roumenina, Lubka T.
    Sorbonne Univ, France.
    Nilsson, Per H.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Oslo Univ Hosp, Norway;Univ Oslo, Norway.
    Heme Interferes With Complement Factor I-Dependent Regulation by Enhancing Alternative Pathway Activation2022In: Frontiers in Immunology, E-ISSN 1664-3224, Vol. 13, article id 901876Article in journal (Refereed)
    Abstract [en]

    Hemolysis, as a result of disease or exposure to biomaterials, is characterized by excess amounts of cell-free heme intravascularly and consumption of the protective heme-scavenger proteins in plasma. The liberation of heme has been linked to the activation of inflammatory systems, including the complement system, through alternative pathway activation. Here, we investigated the impact of heme on the regulatory function of the complement system. Heme dose-dependently inhibited factor I-mediated degradation of soluble and surface-bound C3b, when incubated in plasma or buffer with complement regulatory proteins. Inhibition occurred with factor H and soluble complement receptor 1 as co-factors, and the mechanism was linked to the direct heme-interaction with factor I. The heme-scavenger protein hemopexin was the main contaminant in purified factor I preparations. This led us to identify that hemopexin formed a complex with factor I in normal human plasma. These complexes were significantly reduced during acute vasoocclusive pain crisis in patients with sickle cell disease, but the complexes were normalized at their baseline outpatient clinic visit. Hemopexin exposed a protective function of factor I activity in vitro, but only when it was present before the addition of heme. In conclusion, we present a mechanistic explanation of how heme promotes uncontrolled complement alternative pathway amplification by interfering with the regulatory capacity of factor I. Reduced levels of hemopexin and hemopexin-factor I complexes during an acute hemolytic crisis is a risk factor for heme-mediated factor I inhibition.

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  • 36.
    Ghavidel, Amir
    et al.
    University of Iasi, Romania.
    Bak, Miklós
    University of Sopron, Hungary.
    Hofmann, Tamás
    University of Sopron, Hungary.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Green Sustainable Development.
    Vasilache, Viorica
    University of Iasi, Romania.
    Sandu, Ion
    Academy of Romanian Scientists (AOSR), Romania;Romanian Inventors Forum, Romania.
    Comparison of chemical compositions in wood and bark of Persian silk tree (Albizia julibrissin Durazz)2022In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 17, no 6, p. 759-770Article in journal (Refereed)
    Abstract [en]

    This research was conducted to identify and compare the chemical compositions in Persian silk tree(Albizia julibrissin Durazz.) from different parts of wood and bark, using Fourier Transform Infrared(FTIR) Spectroscopy, gas and liquid chromatography coupled to mass spectrometry (GC-MS, LCMS),and elemental analysis. FTIR analysis showed significant differences in the chemical structureof bark and wood at peaks that belong to the cellulose and hemicelluloses. According to theresults, the C-O-C asymmetric stretch vibration in cellulose and hemicelluloses peak of Persian silktree was lower in the bark and ѵC=O in quinone or p-quinone peak was higher in the bark. Theresults of GC-MS showed 12 chemical constituents in the bark and 43 in the wood, respectively.Among these, hexadecanoic acid and inositol were in common. According to the LC-MS analyses,bark samples were rich in lignan compositions and triterpenoid saponins, whereas wood was poorin these compositions. Altogether 61 compositions have been tentatively identified and describedfrom bark and wood tissues; many of them were identified for the first time. Energy-dispersive Xray(EDX) spectrometry illustrated that the bark contained iron and aluminium, sodium,phosphorus, sulphur and chlorine, while these elements did not exist in wood.

  • 37.
    Ghavidel, Amir
    et al.
    Alexandru Ioan Cuza University, Romania.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Chemical composition of recent and naturally-aged european spruce (Picea abies) and silver fir (Abies alba) woods2020In: Proceedings of the 16th Annual Meeting of the Northern European Network for Wood Science and Engineering – WSE2020 / [ed] Marketta Sipi;Juha Rikala, University of Helsinki, Finland , 2020, p. 29-31Conference paper (Refereed)
  • 38.
    Ghavidel, Amir
    et al.
    Alexandru Ioan Cuza University of Iasi, Romania.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Gelbrich, Jana
    Leibniz-IWT-Institute for Materials Testing, Germany.
    Bak, Miklós
    University of Sopron, Hungary.
    Sandu, Ion
    Alexandru Ioan Cuza University of Iasi, Romania;Academy of Romanian Scientists (AOSR), Romania;Romanian Inventors Forum, Romania.
    Microstructural and Chemical Characteristics of Archaeological White Elm (Ulmus laevis P.) and Poplar (Populus spp.)2021In: Applied Sciences: APPS, E-ISSN 1454-5101, Vol. 11, no 21, article id 10271Article in journal (Refereed)
    Abstract [en]

    The degradation states of archaeological white elm, with an age estimation of ~350 years, and poplar, with an age approximation of ~1000–1200 years, were studied by means of different chemical and microscopy analyses. Recently cut samples from the respective species were used for comparison reasons. The chemical composition analysis of the archaeological samples showed significantly low holocellulose values, while the lignin, extractive, and ash contents were considerably high, as compared with the recently cut samples. The Fourier-transform infrared (FTIR) spectroscopy also confirmed the changes in the chemical structure of the archaeological elm and poplar samples. The light and scanning electron microscopies illustrated that the erosion bacteria were the main degrading agent in both archaeological elm and poplar, although the hyphae of rot fungi were detected inside the vessel elements of the archaeological poplar sample.

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  • 39.
    Ghavidel, Amir
    et al.
    University of Iasi, Romania.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Militz, Holger
    University of Göttingen, Germany.
    Vasilache, Viorica
    University of Iasi, Romania.
    Sandu, Ion
    Academy of Romanian Scientists (AOSR), Romania;Romanian Inventors Forum, Romania.
    Characterization of Archaeological European White Elm (Ulmus laevis P.) and Black Poplar(Populus nigra L.)2020In: Forests, E-ISSN 1999-4907, Vol. 11, no 12, p. 1-13, article id 1329Article in journal (Refereed)
    Abstract [en]

    The present study aims at characterization of freshly-cut and archaeological European white elm and poplar. The archaeological elm sample was buried at a depth of 8–10 m inside of soil with age approximation of ~1800–2000 years old, and the archaeological poplar sample was apart of a boat in a freshwater lake or river with age estimation of ~1000–1200 years. Alteration in the chemical structure of the elm and poplar samples due to the ageing process were confirmed by X-ray photoelectron spectroscopy (XPS). Both archaeological wood (AW) samples illustrated considerably lower cellulose crystallinity than the fresh samples as determined by X-ray diffraction. The sorption behavior of AW and fresh wood (FW) samples were evaluated by means of dynamic vapor sorption (DVS) analysis. Results exhibited a higher equilibrium moisture content (EMC) and sorption hysteresis values in archaeological elm and poplar as compared with the fresh samples. Higher hydrophilicity of the AW samples than the FW ones is attributed to their higher amorphous structure. The extensive degradation of AW samples were also confirmed by scanning electron microscopy (SEM) micrographs.

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  • 40.
    Ghavidel, Amir
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Jorbandian, Amin
    University of Tehran, Iran.
    Bak, Miklós
    University of Sopron, Hungary.
    Gelbrich, Jana
    Leibniz-IWT, Germany.
    Morrell, Jeffrey J.
    University of the Sunshine Coast, Australia.
    Sandu, Ion
    Academy of Romanian Scientists (AOSR), Romania;Romanian Inventors Forum, Romania.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Green Sustainable Development. Michigan Technological University , USA.
    Degradation assessment of archaeological oak (Quercus spp.) buried under oxygen-limited condition2023In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 77, no 3, p. 198-207Article in journal (Refereed)
    Abstract [en]

    The biological deterioration of archaeological wood under oxygen-limited conditions varies due to the limited activities of microorganisms. It is essential to expand the knowledge of the degradation types and the status of archaeological monuments for selecting the proper consolidates. The physical, chemical, and anatomical properties of approximately 600–650 year old archaeological oak collected from an archaeological site in Iasi-Romania were analysed to assess the quality and to identify the degradation types. The results were compared with similar tests on recently-cut oak. X-ray photoelectron spectroscopy (XPS) revealed the presence of more lignin-related peaks in the archaeological oak, which likely reflected the degradation of the wood carbohydrates as evidenced by the decreased oxygen-to-carbon ratio Cox/Cnon-ox. The differences in cellulose crystallinity were not significant suggesting that any cellulose degradation occurred in the amorphous regions. This was also reflected in the dynamic water vapor sorption analysis where the differences in sorption isotherms and hysteresis of archaeological and recently-cut oaks were marginal. Microscopic analysis of the oak cells illustrated bacterial degradation patterns, while the field emission scanning electron microscopy (FESEM) showed the presence of erosion bacteria in the archaeological oak collected from the site with low oxygen conditions.

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  • 41.
    Gholamiyan, Hadi
    et al.
    University of Tehran, Iran.
    Ashouri, Javad
    Shahid Rajaee Teacher Training University, Iran.
    Ahmadi, Peyman
    University of Tehran, Iran.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Green Sustainable Development. Michigan Technological University, USA.
    Surface Wettability and Coating Performance of Plasma-Treated Wood-Based Composite Panels2022In: Coatings, ISSN 2079-6412, Vol. 12, no 12, article id 1894Article in journal (Refereed)
    Abstract [en]

    The effect of dielectric barrier discharge (DBD) plasma treatment was studied on the surface characteristics and coating performance of transparent epoxy resin on the surface of particleboard (PB) and medium-density fiberboard (MDF). The plasma treatment was performed at three plasma energies (10, 15, and 20 kW) and three distances from the nozzle (10, 20, and 30 mm). Analyzing the samples by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) indicated the changes of their chemical structure by means of the plasma treatment. The contact angle study showed a significant increase in surface wettability after plasma treatment with a pronounced effect observed by treatment parameters. The surface roughness was also significantly increased by the plasma treatment. The strength of the coating adhesion to the surface of the PB and MDF composite panels was also significantly improved by the plasma treatment, while no obvious trend was observed by treatment parameters. The highest adhesion strength of 2.03 MPa and 3.63 MPa were obtained by the PB and MDF samples, respectively, treated at a 10 mm nozzle distance and 15 kW plasma energy. The scratch resistance of the epoxy coatings showed a similar trend as the adhesion strength illustrating an inferior isolated surface of the coating after the plasma treatment.

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  • 42.
    Gholamiyan, Hadi
    et al.
    University of Tehran, Iran.
    Gholampoor, Behnam
    University of Tehran, Iran.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Linnaeus University, Linnaeus Knowledge Environments, Green Sustainable Development.
    Application of Waterborne Acrylic and Solvent-Borne Polyester Coatings on Plasma-Treated Fir (Abies alba M.) Wood2022In: Materials, E-ISSN 1996-1944, Vol. 15, no 1, article id 370Article in journal (Refereed)
    Abstract [en]

    This research investigates the effect of plasma treatment with air, nitrogen (N2), and carbon dioxide (CO2) gases on the performance of waterborne (acrylic) and solvent-borne (polyester) coated fir (Abies alba M.) wood samples. The properties of the plasma-coated samples were analyzed before and after exposure to accelerated weathering and compared with those of untreated and solely treated ones. According to pull-off testing, the coating adhesion of the wood samples was considerably improved by plasma treatment, and obvious differences were observed between different plasma gases. The effect was more pronounced after the weathering test. Similar results were obtained for the abrasion resistance of the samples. The water contact angle measurement illustrated more hydrophilic character in the solely plasma-treated wood in comparison with the untreated wood. The application of coatings, however, strongly improved its hydrophobic character. The performances of waterborne and solvent-borne coatings on plasma-treated wood were comparable, although slightly better values were obtained by the waterborne system. Our results exhibit the positive effect of plasma treatment on coating performances and the increased weather resistance of the waterborne and solvent-borne coating systems on plasma-treated wood.

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  • 43.
    Grund Bäck, Lina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. RISE, Sweden.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Karlsson, Stefan
    RISE, Sweden.
    Möncke, Doris
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. National Hellenic Research Foundation, Greece.
    Kamitsos, Efstratios
    National Hellenic Research Foundation, Greece.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Mixed alkali/alkaline earth‐silicate glasses: Physical properties and structure by vibrational spectroscopy2019In: International Journal of Applied Glass Science, ISSN 2041-1286, Vol. 10, no 3, p. 349-362Article in journal (Refereed)
    Abstract [en]

    In this article, we investigate the correlation of selected physical properties with structural changes in quaternary mixed modifier alkali/alkaline earth oxide silicate glass systems, focusing either on the mixed alkali effect [(20−x)Na2O–xK2O–10CaO–70SiO2 (x = 0, 5, 10, 15, 20)] or on the mixed alkaline earth effect [20Na2O–(10−y)CaO–yBaO–70SiO2 (y = 0, 5, 10)]. A maximum microhardness and packing density, as well as a minimum glass transition temperature were observed for mixed alkali glasses. The mixed alkaline earth glasses do not exhibit any clear extrema in any of the properties studied. The hardness and glass transition temperature decreases, while the density and molar volume increases with increasing BaO content. Raman spectroscopy showed an increase in the Q3 group compared to the Q2 and Q4 groups as the high field strength ions Na+ or Ca2+ are substituted by their low field strength analogs K+ or Ba2+. In the mixed alkali series, the high field strength ion Na+, seems to push the low field strength ion K+ into lower energy sites when present simultaneously, while such an effect is not apparent for the mixed alkaline earth glasses, where the far IR spectra of mixed glasses are equivalent to the weighted averages of the pure glasses.

  • 44.
    Grund Bäck, Lina
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. RISE Research Institutes of Sweden, Sweden.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Karlsson, Stefan
    RISE Research Institutes of Sweden, Sweden;Friedrich Schiller University of Jena, Germany.
    Wondraczek, Lothar
    Friedrich Schiller University of Jena, Germany.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    X-ray and UV-Vis-NIR absorption spectroscopy studies of the Cu(I) and Cu(II) coordination environments in mixed alkali-lime-silicate glasses2019In: Journal of Non-Crystalline Solids: X, ISSN 2590-1591, Vol. 3, article id 100029Article in journal (Refereed)
    Abstract [en]

    The local structures of Cu(I) and Cu(II) in (20-x)Na2O-xK2O-10CaO-70SiO2 glasses with a copper content of 0.4 mol% have been investigated by Cu K-edge extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES). Complementary data for Cu(II) was derived using UV–Vis-NIR spectroscopy. Indication for mainly linear two-fold coordination of the Cu+ ion was found by both EXAFS and XANES, but other coordination between Cu+ and O2– cannot be excluded. The Cu(I)O bond lengths were found to be 1.79–1.83 ± 0.02 Å. EXAFS results showed that Cu(II) was mostly present in a Jahn-Teller distorted environment with oxygen, an octahedron with four shorter Cu(II)O bonds and two longer in axial position. The equatorial bond lengths were found to be 1.89–1.91 ± 0.02 Å and the axial 2.20–2.24 ± 0.02 Å with no effect of the Jahn-Teller distortion of the octahedron when the glass composition was altered.

  • 45.
    Hakeem, Abbas Saeed
    et al.
    King Fahd Univ Petr & Minerals, Saudi Arabia.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Hoche, Thomas
    Leibniz Inst Surface Engn IOM, Germany;Fraunhofer Inst Microstruct Mat & Syst IMWS, Germany.
    Drmosh, Qasem Ahmed
    King Fahd Univ Petr & Minerals, Saudi Arabia.
    Khan, Amir Azam
    Natl Univ Sci & Technol, Pakistan.
    Jonson, Bo
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Microstructure Evaluation and Impurities in La Containing Silicon Oxynitrides2021In: Nanomaterials, E-ISSN 2079-4991, Vol. 11, no 8, article id 1896Article in journal (Refereed)
    Abstract [en]

    Oxynitride glasses are not yet commercialised primarily due to the impurities present in the network of these glasses. In this work, we investigated the microstructure and instinctive defects in nitrogen rich La-Si-O-N glasses. Glasses were prepared by heating a powder mixture of pure La metal, Si3N4, and SiO2 in a nitrogen atmosphere at 1650-1800 degrees C. The microstructure and impurities in the glasses were examined by optical microscopy, scanning electron microscopy, atomic force microscopy, and transmission electron microscopy in conjunction with electron energy-loss spectroscopy. Analyses showed that the glasses contain a small amount of spherical metal silicide particles, mostly amorphous or poorly crystalline, and having sizes typically ranging from 1 mu m and less. The amount of silicide was estimated to be less than 2 vol. %. There was no systematic relation between silicide formation and glass composition or preparation temperature. The microstructure examination revealed that the opacity of these nitrogen rich glasses is due to the elemental Si arise from the decomposition reaction of silicon nitride and silicon oxide, at a high temperature above similar to 1600 degrees C and from the metallic silicide particles formed by the reduction of silicon oxide and silicon nitride at an early stage of reaction to form a silicide intermetallic with the La metal.

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  • 46.
    Hakeem, Abbas Saeed
    et al.
    King Fahd University of Petroleum & Minerals, Saudi Arabia.
    Khan, Majid
    King Fahd University of Petroleum & Minerals, Saudi Arabia.
    Ahmed, Bilal Anjum
    National University of Sciences and Technology, Pakistan.
    Ghanim, Ahmed Ali
    King Fahd University of Petroleum & Minerals, Saudi Arabia.
    Patel, Faheemuddin
    King Fahd University of Petroleum & Minerals, Saudi Arabia.
    Ehsan, Muhammad Ali
    King Fahd University of Petroleum & Minerals, Saudi Arabia.
    Ali, Sadaqat
    Imam Abdulrahman bin Faisal University, Saudi Arabia.
    Laoui, Tahar
    University of Sharjah, United Arab Emirates.
    Ali, Sharafat
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Synthesis and characterization of alkaline earth and rare earth doped sialon Ceramics by spark plasma sintering2021In: International journal of refractory metals & hard materials, ISSN 0263-4368, Vol. 97, article id 105500Article in journal (Refereed)
    Abstract [en]

    Several sialon ceramics compositions were synthesized by selecting metal oxides (MOs) in the nanosize range as additives in the oxynitride network. Nanosized precursors, including Si3N4, SiO2, AlN, Al2O3, and MO (MO =MgO, CaO, SrO, BaO, Y2O3, La2O3, CeO2, Nd2O3, Eu2O3, Dy2O3, Er2O3 and Yb2O3,) were used in the present study. Probe sonication and spark plasma sintering techniques were used for mixing the powder precursors and subsequent synthesis of sialon ceramics at a relatively low temperature of 1500 ◦C. Formation of α-sialon(general formula represented by Mm/vSi12-(m+n)Alm+nOnN16-n) was investigated for m and n values of 1.1 and 0.6, respectively and their structural, morphological, thermal, and mechanical properties were evaluated. The synthesized samples were characterized using X-ray diffractometry and field emission scanning electron microscopy to study the effect of the MOs on the microstructure and resulting densification, hardness, fracture toughness, thermal expansion, and thermal conductivity. The sialon samples synthesized using the selected MOs exhibited similar relative densities in the range of 96 to 99% among all the samples and Vickers hardness (HV10) values, in the range of 15 to 20.8 GPa, depending on the type of MO. However, RE MOs exhibited a higher HV than AE MOs.Fracture toughness (KIc) was ~4 MPa⋅m1/2 for most of the samples, but the sample doped with Yb2O3 had the highest KIc of 6.3 MPa⋅m1/2. The thermal conductivity decreased as the atomic number (atomic radii) of the AE increases and in the case of RE exhibited a random tendency. On the other hand, the thermal expansion coefficient increased with increasing atomic radii of the AE, and a mixed trend, with values in the range of 2.63 to2.83 ppm⋅K-1, was observed for RE doped sialon ceramics. These behaviors are attributed to the resulting morphology and structure of alpha sialon comprised of both equiaxed and elongated grains. The properties of these sialon ceramics could be tailored by the proper selection of suitable precursors and synthesis parameters.

  • 47.
    Han, Sang Sub
    et al.
    Univ Cent Florida, USA;Seoul Natl Univ, Republic of Korea.
    Ko, Tae-Jun
    Univ Cent Florida, USA.
    Shawkat, Mashiyat Sumaiya
    Univ Cent Florida, USA.
    Shum, Alex Ka
    Univ Cent Florida, USA.
    Bae, Tae-Sung
    Korea Basic Sci Inst, Republic of Korea.
    Chung, Hee-Suk
    Korea Basic Sci Inst, Republic of Korea.
    Ma, Jinwoo
    North Carolina State Univ, USA.
    Sattar, Shahid
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials. Luleå University of Technology, Sweden.
    Bin Hafiz, Shihab
    New Jersey Inst Technol, USA.
    Al Mahfuz, Mohammad M.
    New Jersey Inst Technol, USA.
    Mofid, Sohrab Alex
    Univ Cent Florida, USA.
    Larsson, J. Andreas
    Luleå University of Technology, Sweden.
    Oh, Kyu Hwan
    Seoul Natl Univ, Republic of Korea.
    Ko, Dong-Kyun
    New Jersey Inst Technol, USA.
    Jung, Yeonwoong
    Univ Cent Florida, USA.
    Peel-and-Stick Integration of Atomically Thin Nonlayered PtS Semiconductors for Multidimensionally Stretchable Electronic Devices2022In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 14, no 17, p. 20268-20279Article in journal (Refereed)
    Abstract [en]

    van der Waals (vdW) crystals with unparalleled electromechanical properties have been explored for transformative devices. Currently, the availability of 2D vdW crystals is rather limited in nature as they are only obtained from certain mother crystals with intrinsically possessed layered crystallinity and anisotropic molecular bonding. Recent efforts to transform conventionally non-vdW three-dimensional (3D) crystals into ultrathin 2D-like structures have seen rapid developments to explore device building blocks of unique form factors. Herein, we explore a "peel-and-stick" approach, where a nonlayered 3D platinum sulfide (PtS) crystal, traditionally known as a cooperate mineral material, is transformed into a freestanding 2D-like membrane for electromechanical applications. The ultrathin (???10 nm) 3D PtS films grown on large-area (>cm2) silicon dioxide/silicon (SiO2/Si) wafers are precisely "peeled" inside water retaining desired geometries via a capillary-force-driven surface wettability control. Subsequently, they are "sticked" on strain-engineered patterned substrates presenting prominent semiconducting properties, i.e., p-type transport with an optical band gap of ∼1.24 eV. A variety of mechanically deformable strain-invariant electronic devices have been demonstrated by this peel-and-stick method, including biaxially stretchable photodetectors and respiratory sensing face masks. This study offers new opportunities of 2D-like nonlayered semiconducting crystals for emerging mechanically reconfigurable and stretchable device technologies.

  • 48.
    Han, Sang Sub
    et al.
    Univ Cent Florida, USA.
    Shawkat, Mashiyat Sumaiya
    Univ Cent Florida, USA.
    Lee, Yoong Hee
    Seoul Natl Univ, Republic of Korea.
    Park, Gyehyun
    Seoul Natl Univ, Republic of Korea.
    Li, Hao
    Univ Cent Florida, USA.
    Chung, Hee-Suk
    Korea Basic Sci Inst, Republic of Korea.
    Yoo, Changhyeon
    Univ Cent Florida, USA.
    Mofid, Sohrab Alex
    Univ Cent Florida, USA.
    Sattar, Shahid
    Linnaeus University, Faculty of Technology, Department of Physics and Electrical Engineering. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Choudhary, Nitin
    Univ Cent Florida, USA.
    Choi, Jea-Young
    Dong A Univ, Republic of Korea.
    Jung, YounJoon
    Seoul Natl Univ, Republic of Korea.
    Jung, Yeonwoong
    Univ Cent Florida, USA.
    Kim, Jung Han
    Dong A Univ, Republic of Korea.
    Wafer-Scale Anion Exchange Conversion of Nonlayered PtS Films to van der Waals Two-Dimensional PtTe2 Layers with Negative Photoresponsiveness2022In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 34, no 15, p. 6996-7005Article in journal (Refereed)
    Abstract [en]

    This study reports on the controlled vapor-phase anion exchange conversion of three-dimensional (3D) platinum(II) sulfide (PtS) thin films to two-dimensional platinum ditelluride (2D PtTe2) van der Waals (vdW) layers. The low temperature (i.e., 400 ?) thermal tellurization of chemical vapor deposition (CVD)-grown PtS thin films leads to the formation of 2D PtTe2 vdW layers with a modulated crystallographic orientation, i.e., a mixture of horizontally and vertically oriented 2D layers. This chemical conversion enables the tunable electrical transport accompanying semiconducting-to-metallic transition as well as negative photoresponsiveness in the 2D PtTe2 layers. Density functional theory (DFT) calculations verify the thermodynamic principle for the conversion in the frame of free energy landscapes. The present work suggests a new chemical route for controlling the atomic and chemical structures of 2D transition metal dichalcogenides (TMDs) toward their wafer-scale modulation of electrical and opto-electrical properties.

  • 49.
    Hemmilä, Venla
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Ahmed, Sheikh Ali
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Ammonium Lignosulfonate Adhesives for Particleboards with pMDI and Furfuryl Alcohol as Crosslinkers2019In: Polymers, E-ISSN 2073-4360, Vol. 11, no 10, p. 1-17, article id 1633Article in journal (Refereed)
    Abstract [en]

    Tightening formaldehyde emission limits and the need for more sustainable materials have boosted research towards alternatives to urea-formaldehyde adhesives for wood-based panels. Lignin residues from biorefineries consist of a growing raw material source but lack reactivity. Two crosslinkers were tested for ammonium lignosulfonate (ALS)—bio-based furfuryl alcohol (FOH) and synthetic polymeric 4,4′-diphenylmethane diisocyanate (pMDI). The addition of mimosa tannin to ALS before crosslinking was also evaluated. The derived ALS adhesives were used for gluing 2-layered veneer samples and particleboards. Differential Scanning Calorimetry showed a reduction of curing temperature and heat for the samples with crosslinkers. Light microscopy showed that the FOH crosslinked samples had thicker bondlines and higher penetration, which occurred mainly through vessels. Tensile shear strength values of 2-layered veneer samples glued with crosslinked ALS adhesives were at the same level as the melamine reinforced urea-formaldehyde (UmF) reference. For particleboards, the FOH crosslinked samples showed a significant decrease in mechanical properties (internal bond (IB), modulus of elasticity (MOE), modulus of rupture (MOR)) and thickness swelling. For pMDI crosslinked samples, these properties increased compared to the UmF. Although the FOH crosslinked ALS samples can be classified as non-added-formaldehyde adhesives, their emissions were higher than what can be expected to be sourced from the particles. 

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  • 50.
    Hemmilä, Venla
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hosseinpourpia, Reza
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. Linnaeus University, Linnaeus Knowledge Environments, Advanced Materials.
    Adamopoulos, Stergios
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Eceiza, Arantxa
    University of the Basque Country UPV/EHU, Spain.
    Characterization of Wood-based Industrial Biorefinery Lignosulfonates and Supercritical Water Hydrolysis Lignin2020In: Waste and Biomass Valorization, ISSN 1877-2641, E-ISSN 1877-265X, Vol. 11, no 11, p. 5835-5845Article in journal (Refereed)
    Abstract [en]

    Understanding the properties of any particular biorefinery or pulping residue lignin is crucial when choosing the right lignin for the right end use. In this paper, three different residual lignin types [supercritical water hydrolysis lignin (SCWH), ammonium lignosulfonate (A-LS), and sodium lignosulfonate (S-LS)] were evaluated for their chemical structure, thermal properties and water vapor adsorption behavior. SCWH lignin was found to have a high amount of phenolic hydroxyl groups and the highest amount of beta-O-4 linkages. Combined with a low ash content, it shows potential to be used for conversion into aromatic or platform chemicals. A-LS and S-LS had more aliphatic hydroxyl groups, aliphatic double bonds and C=O structures. All lignins had available C-3/C-5 positions, which can increase reactivity towards adhesive precursors. The glass transition temperature (T-g) data indicated that the SCWH and S-LS lignin types can be suitable for production of carbon fibers. Lignosulfonates exhibited considerable higher water vapor adsorption as compared to the SCWH lignin. In conclusion, this study demonstrated that the SCWH differed greatly from the lignosulfonates in purity, chemical structure, thermal stability and water sorption behavior. SCWH lignin showed great potential as raw material for aromatic compounds, carbon fibers, adhesives or polymers. Lignosulfonates are less suited for conversion into chemicals or carbon fibers, but due to the high amount of aliphatic hydroxyl groups, they can potentially be modified or used as adhesives, dispersants, or reinforcement material in polymers. For most value-adding applications, energy-intensive purification of the lignosulfonates would be required. [GRAPHICS] .

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