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Thin solid pixels made of Ag/PMMA stacks have been fabricated by laser-induced forward transfer (LIFT), to be tested as thin film microcapacitors in organic electronics applications. The square-shaped laser-printed pixels have a lateral size of ∼350 μm, and the thickness of the dielectric film was varied between 100 and 1500 nm. The pixels were deposited on electrode structures made by LIFT printing of silver nanoparticles ink and paste. Optimal printing conditions led to the fabrication of microcapacitors with typical capacitance in the pF range, tuned by changing the properties of the multilayered structure (e.g. pixel size and/or thickness of the dielectric). Their stability was also investigated over time. We discuss on the morphological and electrical properties of such laser-printed structures, with respect to the impact resistance of the polymer and its suitability for the LIFT process. [ABSTRACT FROM AUTHOR]

Carbon nanowalls (CNW) are two-dimensional interconnected graphitic nanostructures that have a few μm in length and height, reaching typical thicknesses of a few tens of nm. We present results on such layers synthesized in a low pressure argon plasma jet, injected with acetylene and hydrogen, on transparent substrates (quartz) heated at 600 °C, without catalyst. Thermogravimetric analysis reveals that the CNW are stable up to 420 °C in air, and Raman spectroscopy investigations highlight their graphene-like structure. Finally, using a pulsed Nd:YAG laser device (355 nm, 50 ps), we show that 2D-arrays of CNW (pixels and lines) can be printed by laser-induced forward transfer (LIFT), preserving their architecture and structure. Electrical measurements on 1 μm thick CNW demonstrate typical values in the range of 357.5–358.4 Ω for the samples grown on Au/Cr electrodes, and in the range of 450.1–474.7 Ω for the LIFT printed lines (under positive, negative, and neutral polarization; 1 kHz–5 MHz frequency range; 500 mV and 1 V, respectively). Their morphology is highlighted by means of optical and electronic microscopy. Such structures have potential applications as soft conductive lines, in sensor development and/or embedding purposes. [ABSTRACT FROM AUTHOR]

Thermal behavior studies of several polymers, i.e. polyvinyl chloride (PVC), polyacrylic acid (PAA), and polyaniline (PAni), together with thin film deposition by a MAPLE technique, are presented. Thermal stability studies are important before attempting any laser-assisted processing of such materials, as this provides a better understanding of their molecular behavior, to assess the evolution and dynamics of the deposition. Thin films were grown on silicon substrates by means of matrix-assisted pulsed laser evaporation (MAPLE) using a Nd:YAG laser (266 and 355 nm, 7 ns pulse duration). Above the fluence of ~0.7 J/cm 2 the polymeric films are highly non-uniform due to the transferring of matrix-droplets and/or clusters from the target. At low fluence, typically between 0.1 and 0.5 J/cm 2 , the polymeric films are intact; the surface morphology is substantially improved and there are no measurable traces of the matrix molecules in the films. The important question of polymeric molecules integrity in the films with respect to that of the targets is discussed, in relation to their properties, and compared to data available in the literature. [ABSTRACT FROM AUTHOR]

There is a dire need to develop an algorithm to improve the recognition of acquired hemophilia A and B (AHA and AHB) in clinical practice. Initial and intensive care unit (ICU) management of the disorder is particular and represents a challenge for the internist/hematologist and the ICU physician. A delay in the proper treatment of bleeding episodes can lead to a life-threatening event. Expert advice should be sought as soon as possible. Succesful resolution involves accurate diagnosis, bleeding control with hemostatic and immunotherapy, and eradication of the autoantibodies to improve overall survival. Current treatment guidelines are based on the literature in the form of cases and observational studies due to a lack of randomized controlled trials. AH can be triggered by many pathologies, presenting as a paraneoplastic syndrome in case of malignancies or as surgical associated acquired hemophilia (SAHA). We have reviewed the literature from 2015 to 2021 regarding the new case reports to further assess if there is an improvement in the clinical approach. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ferrocenecarboxaldehyde thin films are grown on silicon substrates, by MAPLE. [•] Thin films with low roughness and preserved chemical structure are obtained. [•] Second harmonic generation capabilities of films are evidenced. [Copyright &y& Elsevier]

Abstract: Ferrocene – Fe(C5H5)2, the prototypical metallocene, is a type of organometallic chemical compound consisting of two cyclopentadienyl rings bound on opposite sides of a central iron atom. We discuss here on the growth of high quality, nanometric-sized ferrocene thin films by a non-conventional technique, i.e. matrix-assisted pulsed laser evaporation (MAPLE), on silicon and ITO coated glass substrates, by using a Nd:YAG pulsed laser device emitting at 266 nm (4ω). Spectroscopic-ellipsometry, Fourier transform infrared spectroscopy, scanning electron microscopy and atomic force microscopy techniques were used to investigate the structure, morphology and optical properties of the films. Low-to-medium second harmonic generation capabilities of the films were evidenced, when irradiated by a femtosecond Ti:sapphire pulsed laser. [Copyright &y& Elsevier]

We present results on a new, laboratory synthesized ferrocene-derivative , i.e. 4-(ferrocenylmethylimino)-2-hydroxy-benzoic acid. Thin films with controlled thickness are deposited by matrix-assisted pulsed laser evaporation (MAPLE), on quartz and silicon substrates, with the aim of evaluating the nonlinear optical properties for potential optoelectronic applications. Dimethyl sulfoxide was used as matrix, with 1% wt. concentration of the guest compound. The frozen target is irradiated by using a Nd:YAG laser (4 ω /266 nm, 7 ns pulse duration, 10 Hz repetition rate), at low fluences ranging from 0.1 to 1 J/cm 2 . Atomic force microscopy (AFM) and scanning electron microscopy (SEM) are used to probe the surface morphology of the films. Fourier transform infrared (FTIR) and Raman spectroscopy reveal similar structure of the thin film material when compared to the starting material. The optical properties of the thin films are investigated by spectroscopic-ellipsometry (SE), and the refractive index dependence with respect to temperature is studied. The second harmonic generation (SHG) potential is assessed by using a femtosecond Ti:sapphire laser (800 nm, 60–100 fs pulse duration, 80 MHz repetition rate), at 200 mW maximum output power, revealing that the SHG signal intensity is strongly influenced by the films’ thickness. [ABSTRACT FROM AUTHOR]

We report on the thin film growth of 1,2,3,4,5,6,7,8-octahydroacridine (OHA) by matrix-assisted pulsed laser evaporation (MAPLE), starting from a frozen solution of 1% OHA dissolved in methanol and using a Nd:YAG laser emitting at 266 nm wavelength with fluences in the range 0.1–1 J/cm 2 . The optical properties were studied by spectroscopic-ellipsometry (SE), while Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were performed for structure and surface morphology investigation. Second harmonic generation (SHG) capabilities of the thin films were investigated by using a tunable Ti:sapphire laser with maximum emission centred in near infra-red. The peak of emitted photons is located at 388 nm, therefore half the wavelength of the initial photons (776 nm). The semi logarithmic dependence of SHG intensity on incident power is almost linear, except the value obtained at highest power of incident photons. This value indicates a local changing of sample due to the heating produced by the high-power incident beam. [ABSTRACT FROM AUTHOR]

Solution precursor plasma spraying (SPPS) is a promising method of obtaining coatings with unique microstructural features. The present study reports about the development of hydroxyapatite (HA) coatings by SPPS using water-based calcium-phosphate solution and about the analyses of their microstructure. X-ray diffraction (XRD) analysis showed that HA was the major crystal phase of the coatings, being present in the range from 95% to 98%. The coatings of greater HA content were obtained while spraying using shorter spray distance. The coating crystallinity ranges from 24% to 69% depending on the temperature at deposition. An increase of the temperature results in greater crystallinity. The obtained coatings' microstructures may be described by dome-like surface and by the columnar-like cross-section when using precursor with low concentration. The use of concentrated solution precursor results in cauliflower-like structures composed of agglomerated fragmented shells and fine spherical particles. The possible phenomena occurring in droplets in contact with the plasma jet and the coating build-up mechanisms were tentatively explained. [ABSTRACT FROM AUTHOR]

[Display omitted] • Modifications of Au micro-objects on sapphire by solid-state de-wetting process. • Au triangular nanoplatelets arrays embedded inside VO 2 thin film: a smart composite. • Modulation of the infrared localized surface plasmon resonance using temperature. • Red-shift resonance explained by the formation of a core–shell metallic structure. Localized surface plasmon resonances (LSPR) make systems capable of concentrating and amplifying light intensity at their near surface. Applications ranging from energy harvesting to biological sensors depend on the modulation of LSPR. Through the synthesis and shape modifications of Au quasi-triangular nanoplatelets (QTP) arrays, LSPR modulation from near- to mid- infrared (∼1.5 μm to ∼ 4.5 μm) is revealed. Au QTP arrays are then associated to a thermochromic vanadium dioxide (VO 2) layer leading to a "smart" nanocomposite exhibiting modulated absorptions. The VO 2 layer acts as a phase change material with a tunable dielectric function vs. temperature and represents an active matrix. The dynamics of the geometric changes in QTP arrays and the phase transition of the matrix are directly correlated to the shift of the LSPR position (Δλ LSPR ∼ 675 nm). The experimental data are supported by a theoretical approach via the finite difference time domain (FDTD) method that provides the LSPR characteristics in the various Au QTP array and nanocomposite configurations. The experimental and modelling investigations prove that the red-shift resonance modulation originates from the creation of a temperature-dependent core–shell structure of Au QTP (core) surrounded by a thin metallic VO 2 layer (shell) and embedded into the VO 2 dielectric matrix. [ABSTRACT FROM AUTHOR]