This study aims to investigate the influence of atmospheric plasma treatment on the abrasion resistance of particleboards, as an example of a wood-based material, coated with a waterborne finish. The ...treatment of the substrate, prior to coating application, using a floating-electrode dielectric barrier discharge (FE-DBD) plasma, resulted in an enhanced abrasion resistance of the coated particleboards in comparison to the untreated ones during the abrasion test with a duration of 200 revolutions. This finding was related to lower contact angles of water and coating after treatment with plasma and greater hardness of the coating on the treated substrates. The micrographs of the sample cross sections recorded with scanning electron microscope showed differences in the amounts of remained coating on the abraded areas. Investigation with attenuated total reflection Fourier transform infrared spectroscopy revealed that treatment of the substrate with plasma did not affect the chemical composition nor the curing and structure of the later applied coating. Further studies should be performed to determine the resistance properties of such surface systems to other impacts.
Cilj ovog rada bio je istražiti utjecaj atmosferske plazme na otpornost iverica na abraziju, kao primjer materijala na bazi drva premazanoga vodenim premazom. Tijekom ispitivanja abrazije u trajanju od 200 ciklusa obrada iverica uz pomoć plazme (FE-DBD) prije nanošenja premaza rezultirala je poboljšanom otpornošću premazanih iverica na abraziju u usporedbi s neobrađenom ivericom. Rezultat istraživanja povezan je s nižim kontaktnim kutom vode i premaznog materijala nakon obrade iverica plazmom i s većom tvrdoćom premaza na podlozi obrađenoj plazmom. Mikrografi je presjeka uzorka dobivene pretražnim elektronskim mikroskopom pokazale su razlike u količini preostalog premaza na površinama ispitanima na otpornost na habanje. Ispitivanje infracrvenom spektroskopijom uz prigušenu totalnu refleksiju pokazalo je da obrada podloge plazmom nije utjecala na kemijski sastav ni na otvrdnjavanje i strukturu kasnije nanesenog premaza. Potrebno je provesti daljnja ispitivanja kako bi se dodatno utvrdila otpornost takvih površinskih sustava.
This paper presents a novel method of partially liquefying bark sawmilling waste for use in making particleboards. Maritime pine (Pinus pinaster Ait.) bark of different particle sizes (fine, medium, ...coarse, and mixed) was partially liquefied in the presence of ethylene glycol as a solvent and sulphuric acid as a catalyst at 180 degrees C for 30 minutes. Single-layer particleboards were prepared by mixing partially liquefied bark (PLB) and wood chips at a ratio of 0.25 with no adhesives (group A) and at ratios of 0.25 or 0.1 with melamine-urea-formaldehyde (MUF) adhesives for additional bonding (groups B and C respectively). Mechanical and physical properties of the particleboards were tested according to European standards. The results showed that the boards in group A had lower densities, inferior mechanical properties and higher moisture content than those in groups B and C. Bark particle size had a significant effect on the mechanical properties of particleboards within each group. Additional MUF bonding and avoidance of coarse bark particles had a positive effect on mechanical properties. The thickness swelling (TS) and water absorption (WA) values of MUF-bonded boards were lower than those of boards without MUF, and greater addition of PLB produced particleboards with better water resistance. Bark particle size was not as critical for TS and WA as for mechanical properties. The overall results suggested using a bark particle size of < 2 mm for further studies.
Future HEP experiments require detailed simulation and advanced reconstruction algorithms to explore the physics reach of their proposed machines and to design, optimise, and study the detector ...geometry and performance. To synergize the development of the CLIC and FCC software efforts, the CERN EP R&D roadmap proposes the creation of a “Turnkey Software Stack”, which is foreseen to provide all the necessary ingredients, from simulation to analysis, for future experiments; not only CLIC and FCC, but also for proposed Super-tau-charm factories, CEPC, and ILC. The software stack will facilitate writing specific software for experiments ensuring coherency and maximising the re-use of established packages to benefit from existing solutions and community developments, for example, ROOT, Geant4, DD4hep, Gaudi and podio. As a showcase for the software stack, the existing CLIC reconstruction software, written for iLCSoft, is being to be ported to Gaudi. In parallel, the back-end of the LCIO event data model can be replaced by an implementation in podio. These changes will enable the sharing of the algorithms with other users of the software stack.
We will present the current status and plans of the turnkey software stack, with a focus of the adaptation of the CLIC reconstruction chain to Gaudi and podio, and detail the plans for future developments to generalise their applicability to FCC and beyond.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Janus crystals represent an exciting class of 2D materials with different atomic species on their upper and lower facets. Theories have predicted that this symmetry breaking induces an electric field ...and leads to a wealth of novel properties, such as large Rashba spin–orbit coupling and formation of strongly correlated electronic states. Monolayer MoSSe Janus crystals have been synthesized by two methods, via controlled sulfurization of monolayer MoSe2 and via plasma stripping followed thermal annealing of MoS2. However, the high processing temperatures prevent growth of other Janus materials and their heterostructures. Here, a room‐temperature technique for the synthesis of a variety of Janus monolayers with high structural and optical quality is reported. This process involves low‐energy reactive radical precursors, which enables selective removal and replacement of the uppermost chalcogen layer, thus transforming classical transition metal dichalcogenides into a Janus structure. The resulting materials show clear mixed character for their excitonic transitions, and more importantly, the presented room‐temperature method enables the demonstration of first vertical and lateral heterojunctions of 2D Janus TMDs. The results present significant and pioneering advances in the synthesis of new classes of 2D materials, and pave the way for the creation of heterostructures from 2D Janus layers.
Janus crystals represent an exciting class of 2D materials with different atomic species on their upper and lower facets. Theories predict that this broken symmetry leads to a wealth of novel properties. A room‐temperature technique for the synthesis of a variety of Janus monolayers and their lateral and vertical heterostructures with high structural and optical quality is reported.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The effect of heat treatment temperature on the elemental composition of Scots pine sapwood (
Pinus sylvestris) has been investigated in the range of temperatures between 220 and 250 °C. The results ...revealed an important increase of carbon content, while oxygen content significantly decreases. Independently of the heat treatment temperature, elemental composition is strongly correlated with the mass losses due to thermal degradations. Carbon content as well as O/C ratio seem to represent valuable markers to estimate wood degradation after heat treatment. Heat treated specimens were exposed to fungal decay using the brown rot fungus
Poria placenta and the weight losses due to fungal degradation were determined. Correlations between weight losses recorded after fungal exposure and elemental composition indicated that carbon content or O/C ratio can be used to predict wood durability conferred by heat treatment allowing us to envisage the development of a proper method to evaluate the quality of heat treated wood and predict its durability. These results also confirm that chemical modifications of wood cell wall polymers are the main factors responsible for wood durability improvement against fungal decay after heat treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Wettability of Norway spruce modified by a new vacuum thermal modification procedure was studied. The mass loss caused by this process ranged from almost 0% when treated at 140 °C to 4.3% at 210 °C. ...Apparent contact angles of water, formamide, and diiodomethane were measured by the Wilhelmy plate method on the specimens taken from the centers of the thermally modified wood samples. For the treatment at the highest temperature, the contact angle of water was significantly higher when compared to untreated spruce (96.6° vs. 83.6°); lower treatment temperatures, however, did not result in a clear correlation between treatment temperature and contact angle. Formamide yielded lower contact angles for treated spruce compared to the untreated one, but without clear influence of the treatment temperature and diiodomethane always gave perfect wetting. Surface energy calculations according to the Owens, Wendt, Rabel, and Kaelble method revealed that the thermal modification process in vacuum increased the surface free energy and lowered the polarity of wood significantly only at the highest applied temperature (210 °C); the treatment had only limited effect at lower temperatures of modification. These results indicate that adequate wetting and adhesion can be achieved on the surfaces of Norway spruce thermally modified in vacuum.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Nanoplasmonic systems combined with optically active two-dimensional materials provide intriguing opportunities to explore and control light–matter interactions at extreme subwavelength length scales ...approaching the exciton Bohr radius. Here, we present room- and cryogenic-temperature investigations of a MoSe2 monolayer on individual gold dipole nanoantennas. By controlling nanoantenna size, the dipolar resonance is tuned relative to the exciton achieving a total tuning of ∼130 meV. Differential reflectance measurements performed on >100 structures reveal an apparent avoided crossing between exciton and dipolar mode and an exciton–plasmon coupling constant of g = 55 meV, representing g/(ℏω X ) ≥ 3% of the transition energy. This places our hybrid system in the intermediate-coupling regime where spectra exhibit a characteristic Fano-like shape. We demonstrate active control by varying the polarization of the excitation light to programmably suppress coupling to the dipole mode. We further study the emerging optical signatures of the monolayer localized at dipole nanoantennas at 10 K.
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IJS, KILJ, NUK, PNG, UL, UM
Liquefied wood-based polyurethane wood coatings of an aesthetically acceptable light colour were prepared and characterised. Liquefied black poplar wood was obtained by solvolysis in a polyethylene ...glycol/glycerol mixture, and it was bleached with hydrogen peroxide. The bleaching treatment converted liquefied wood from a dark brown to a yellowish product. Polyurethane films were prepared by the curing of liquefied wood with polymeric diphenylmethane diisocyanate or trimethylolpropane toluene diisocyanate prepolymer (TMP/TDI) isocyanate-type hardeners. It was found that the selected properties of the films prepared from the bleached liquefied wood were, in general, equivalent to those prepared from unbleached liquefied wood. The mechanical properties of the films obtained with the TMP/TDI curing agent were acceptable for wood coating applications. The initial poor resistance of the films to water and ethanol was substantially improved by the addition of n-octyltriethoxysilane to the liquefied wood prior to the preparation of the polyurethane coatings; the hardness of the films also increased.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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