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V prispevku je predstavljena uporaba nizkotemperaturne plazme, ustvarjene v zraku pri atmosferskem tlaku, za obdelavo površin lesa z namenom izboljšanja njihove omočljivosti. Uporabljena je bila naprava s plazemsko razelektritvijo s površinsko oviro, v konfiguraciji s plavajočo elektrodo. Izkazalo se je, da sta gostota in homogenost plazemske razelektritve, ki se je tvorila med izoliranima visoko napetostnima elektrodama in površino lesa smreke (Picea abies (L.) Karst.) in bukve (Fagus sylvatica L.), zelo odvisni od velikosti razmika med elektrodo in lesom. Meritve topografije s konfokalnim laserskim mikroskopom so pokazale, da obdelava lesa s plazmo na njegovi površini povzroči spremembe na submikroskopskem nivoju. Meritve stičnih kotov kapljic vode in premaza na vodni osnovi so pokazale izboljšano dovzetnost za omočitev obdelanih površin. Zaznati je bilo tudi razlike v omočljivosti površin, v odvisnosti od izbranih parametrov pri obdelavi: vrste lesa, podajalne hitrosti obdelovanca, razdalje med elektrodama, razdalje med elektrodama in obdelovancem ter debeline obdelovanca.

Bacterial contamination of the membranes used during guided bone regeneration directly influences the outcome of this procedure. In this study, we analyzed the early stages of bacterial adhesion on two commercial dense polytetrafluoroethylene (d-PTFE) membranes in order to identify microstructural features that led to different adhesion strengths. The microstructure was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR). The surface properties were analyzed by atomic force microscopy (AFM), scanning electron microscopy (SEM), and surface free energy (SFE) measurements. Bacterial properties were determined using the microbial adhesion to solvents (MATS) assay, and bacterial surface free energy (SFE) was measured spectrophotometrically. The adhesion of four species of oral bacteria (Streptococcus mutans, Streptococcus oralis, Aggregatibacter actinomycetemcomitas, and Veilonella parvula) was studied on surfaces with or without the artificial saliva coating. The results indicated that the degree of crystallinity (78.6% vs. 34.2%, with average crystallite size 50.54 nm vs. 32.86 nm) is the principal feature promoting the adhesion strength, through lower nanoscale roughness and possibly higher surface stiffness. The spherical crystallites (“warts”), observed on the surface of the highly crystalline sample, were also identified as a contributor. All bacterial species adhered better to a highly crystalline membrane (around 1 log10CFU/mL difference), both with and without artificial saliva coating. Our results show that the changes in polymer microstructure result in different antimicrobial properties even for chemically identical PTFE membranes.

Cilj študije je bil priprava bionanokompozita na osnovi polimlečne kisline (PLA) z dodatkom nanofibrilirane celuloze (NFC) kot ojačitvene komponente. Za izdelavo kompozita smo uporabili nemodificirano in acetilirano NFC (A_NFC). NFC, posušeno z zamrzovanjem, smo acetilirali v heterogenem sistemu z acetanhidridom v dimetilformamidu (DMF) ob prisotnosti piridina kot katalizatorja. Uspešnost acetiliranja smo ugotavljali z infrardečo (FT-IR) spektroskopijo. Pripravili smo PLA filme z 2,5 %, 5 % in 10 % dodatkom nemodificirane oziroma acetilirane NFC. Osredotočili smo se na proučevanje vpliva dodatka NFC na prosojnost bionanokompozita in na njegovo odpornost proti razenju. Prosojnost bionanokompozitnega filma smo merili z UV-Vis spektrofotometrijo, odpornost površine filmov proti razenju pa smo ovrednotili z vzmetnim svinčnikom. Določili smo optimalno količino dodane NFC in A_NFC polimeru PLA za doseganje boljše odpornosti proti razenju. Ugotovili smo, da z dodatkom 2,5 % A_NFC dosežemo najboljšo odpornost pripravljenega bionanokompozita proti razenju, ki ima tudi minimalno zmanjšano prosojnost glede na PLA film. Celo z najvišjim dodatkom A_NFC k PLA polimeru smo dobili bionanokompozitne folije z minimalnim zmanjšanjem prosojnosti The aim of the study was to prepare a bionanocomposite based on polylactic acid (PLA) with the addition of nanofibrillated cellulose (NFC) as a reinforcement component. For the production of the composite we used unmodified and acetylated NFC (A_NFC). Freeze-dried NFC was acetylated in a heterogeneous system with acetic anhydride in dimethylformamide (DMF) in the presence of pyridine as a catalyst. The success of the acetylation was determined by FT-IR spectroscopy. PLA films were prepared with the addition of 2.5%, 5% and 10% of unmodified and acetylated NFC. The focus of this research was the impact of the NFC additive on the transparency and on the resistance of the bionanocomposite to scratching. The transparency of the bionanocomposite film was measured using UV-Vis spectrophotometry, and the resistance of the films to scratching was evaluated with a scratch test. The optimal amount of NFC and A_NFC added to the polymer PLA to achieve better resistance of the bionanocomposite to scratching was determined. The best resistance of the prepared bionanocomposite to scratching was achieved by the addition of a 2.5% A_NFC to the PLA polymer, which also has minimal reduced transparency with respect to the PLA film. With the highest addition of A_NFC to the PLA polymer, bionanocomposite films with minimal reduction of transparency were obtained.

Presentation of the project NewSiest and basic data of this project at the conference "9th Development Day of the Slovenian Forest Based Sector", Ljubljana, Slovenia

This dataset includesthe supplementary informationrelated to the manuscript: Authors: ŽigonJ, Pavlič M, Petrič M, Dahle S Title:Influence of artificial weathering on coated MDF pre-treated with atmospheric plasma

This dataset includesthe supplementary informationrelated to the manuscript: Authors: ŽigonJ, Pavlič M, Kibleur P, Van den BulckeJ, Petrič M, Van Acker J, Dahle S Title:Treatment of wood with atmospheric plasma discharge: Study of the treatment process, dynamic wettability and interactions with a waterborne coating

This paper is the presentation of the NewSiest project at IRG/WP conference:Thermal modification is a process which improves the properties of wood, resulting in a materialthat can be disposed at the end of the product life cycle without presenting an environmentalhazard. Thermally modified wood retains as a natural product and the grain, original colourvariances and characteristics of wood are still present. However, exposure to daylight causes brightening or greying of heat-treated wood surfaces. In order to tackle thischallenge, we areproposing a novel way to improve the UV stability of thermally modified wood using nano basedstabilizers. But instead of coating nanoparticles on heat treated wood, wood surfaces will be treatedwith nanoparticle (ZnO or CeO2) solutions, thereby forming protective envelope on a woodensurface, which will be further heat treated under controlledtemperature and time.

A short description and presentation of the NewSiest project in a professional journal

Together with the recent CLIC detector model CLICdet a new software suite was introduced for the simulation and reconstruction of events in this detector. This note gives a brief introduction to CLICdet and describes the CLIC experimental conditions at 380 GeV and 3 TeV, including beam-induced backgrounds. The simulation and reconstruction tools are introduced, and the physics performance obtained is described in terms of single particles, particles in jets, jet energy resolution and flavour tagging. The performance of the very forward electromagnetic calorimeters is also discussed.

We report an observation of the $B^{pm } to J/psi eta K^{pm }$ and $B^0 to J/psi eta K^0_S$ decays using $772times 10^{6}Boverline {B}$ pairs collected at the $Upsilon (4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We obtain the branching fractions ${mathcal B}(B^{pm }rightarrow J/psi eta K^{pm })=(1.27pm 0.11(hbox {stat.})pm 0.11(hbox {syst.}))times 10^{-4}$ and ${mathcal B}(B^0to J/psi eta K^0_S)=(5.22 pm 0.78 (hbox {stat.}) pm 0.49 (hbox {syst.}))times 10^{-5}$. We search for a new narrow charmonium(-like) state $X$ in the $ J/psi eta$ mass spectrum and find no significant excess. We set upper limits on the product of branching fractions, ${mathcal B}(B^pm to XK^pm){mathcal B}(X to J/psi eta)$, at $3872,hbox {MeV},c^{-2}$ where a $C$-odd partner of $X(3872)$ may exist, at $psi (4040)$ and $psi (4160)$ assuming their known mass and width, and over a range from 3.8 to $4.8,hbox {GeV},c^{-2}$. The obtained upper limits at 90% confidence level for $X^{Chbox {-}{rm odd}}(3872)$, $psi (4040)$, and $psi (4160)$ are $3.8times 10^{-6}$, $15.5times 10^{-6}$, and $7.4times 10^{-6}$, respectively.

We report a high-statistics measurement of the differential cross section of the process $gamma gamma to K^0_S K^0_S$ in the range $1.05,{mathrm {GeV}} leq W leq 4.00$ , where W is the center-of-mass energy of the colliding photons, using 972 $^{-1}$ of data collected with the Belle detector at the KEKB asymmetric-energy e+e− collider operated at and near the $Upsilon$-resonance region. The differential cross section is fitted by parameterized S-, $D_0$, $D_2$-, $G_0$-, and $G_2$-wave amplitudes. In the $D_2$ wave, the $f_2$(1270), $a_2$(1320), and $f′_2$(1525) are dominant and a resonance, the $f_2$(2200), is also present. The $f_0$(1710) and possibly the $f_0$(2500) are seen in the S wave. The mass, total width, and product of the two-photon partial decay width and decay branching fraction to the $K bar {K}$ state $Gamma _{gamma gamma }mathcal {B}(K bar {K})$ are extracted for the $f′_2$(1525), $f_0$(1710), $f_2$(2200), and $f_0$(2500). The destructive interference between the $f_2$(1270) and $a_2$(1320) is confirmed by measuring their relative phase. The parameters of the charmonium states $chi _{c0}$ and $chi _{c2}$ are updated. Possible contributions from the $chi _{c0}(2P)$ and $chi _{c2}(2P)$ states are discussed. A new upper limit for the branching fraction of the P- and CP-violating decay channel $eta _c to K^0_S K^0_S$ is reported. The detailed behavior of the cross section is updated and compared with QCD-based calculations.