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• Geopolymers with CDW aggregates were optimized for producing architectural panels. • Final materials were characterized from a mechanical and physical standpoint. • Aspect ratio and size of specimens were compared to concrete/mortar provisions. • Splitting was correlated to compressive strength through numerous tested geopolymers. • Recyclability of geopolymers as waste aggregates was preliminarily assessed. The paper presents the mechanical and physical characterization of a metakaolin-slag-fly ash-potassium silicate geopolymer mortar embedding inorganic recycled aggregates from Construction and Demolition Waste (CDW). The binder was holistically optimized to comply with the pilot plant requirements for producing architectural panels of satisfactory quality, among them: reduced viscosity, minimum open time of 1 h, use of commercial reagents, sufficient strength and limited shrinkage. Size and aspect ratio of small scale cylindrical specimens were investigated in compression, comparing the performance of tested geopolymers to available provisions for natural rocks, cement concrete and mortars. Empirical correlations between compressive and splitting tensile strength were calibrated through the results of about 130 geopolymer mixtures produced in former and current activities. Lastly, the suitability of reusing geopolymers at their end-of-life as recycled aggregates in a new geopolymer production was preliminarily assessed to explore the feasibility of a closed-loop process. [ABSTRACT FROM AUTHOR]

The use of dispersions of poly(vinyl alcohol) PVA and detonation nanodiamond (DND) as novel inks for 3D printing of variously shaped objects using a layer-by-layer additive manufacturing method is reported. In parallel with the nanocomposites preparation, we designed a 3D printing apparatus and settled protocols for the shaping of hybrid materials, choosing PVA-DND inks as a model system to test the performances of the 3D apparatus. Along with material design and preparation, we discuss the main factors influencing the quality of the final printed objects and enlighten the importance of the matching between the chemical/physical properties of the materials to be extruded and the characteristics of the 3D printer. The thermal and mechanical properties of the printed systems have been tested by Differential Scanning Calorimetry and Contact Resonance Atomic Force Microscopy. The analysis of the mechanical properties of the 3D printed objects evidenced, for 0.5% w/w , 1% w and 5% w DND-loaded nanocomposites, values of mean indentation modulus that are 22%, 44% and 200% higher, respectively, than that of the unloaded PVA. The results of the present research, indicate that an appropriate methodology is able to print PVA-DND nanocomposites in well-defined and shaped structures, suitable for a variety of possible applications. [ABSTRACT FROM AUTHOR]

Abstract: Background: It is known that the incidence of endothelial dysfunction in patients with vascular erectile dysfunction (ED) is increased. The effects of daily vardenafil on endothelial function and arterial stiffness in patients with erectile dysfunction (ED) have never been investigated. Methods: 20 men complaining vascular ED (mean IIEF5=12±6 and peak systolic velocity-PSV=24±2cm/s) were enrolled in a 4-week, randomized, double-blind, double-dummy, crossover study (mean age 59±11) and received either vardenafil 10mg daily or 20mg on-demand with a two-week washout interval. Primary endpoints were variation from baseline of reactive hyperemia (RH) and augmentation index (AI) calculated by fingertip peripheral arterial tonometry (PAT) device. Secondary endpoints were variations of IIEF-5 and SEP3 scores from baseline and plasma surrogate markers of endothelial function, i.e. endothelin-1 (ET-1) and adrenomedullin (ADM). Results: Patients who took daily vardenafil (vs. on-demand) reported significant (P<0.01) improvements in arterial stiffness as evaluated by AI and reduction of plasma ADM levels (p<0.05) but no improvement in average RH. When corrected for heart rate, ADM showed a strong direct relationship with AI (r2 =0.22; p<0.005). The proportion of patients with an IIEF5 score of ≥22 or in SEP3 percentage of success rates were similar. Each treatment resulted in significantly greater IIEF5 scores (p<0.001) and better SEP3 response rates (p<0.0001) compared with baseline. Conclusions: We demonstrated that daily vardenafil improves arterial stiffness and erectile function measurements in men with severe vasculogenic ED. This effect may be mediated, at least in part, by a reduction in ADM circulating levels. [Copyright &y& Elsevier]

Abstract: Alumina (Al2O3) coatings of different thickness were deposited on OT59 brass substrate (BS) using the metal organic chemical vapour deposition (MOCVD) technique to evaluate the corrosion performance by EIS measurements. The used precursor was dimethyl-aluminium-isopropoxide. Electrochemical characterizations of the deposited films were performed in a standard very aggressive acidic solution (aerated 1N H2SO4 at 25°C up to 168h of immersion time) by means of direct current method (Tafel curves) and electrochemical impedance spectroscopy (EIS). The Rutherford backscattering spectroscopy (RBS) indicated that the films are very pure with the correct Al2O3 stoichiometry, while the IR absorption spectra showed that the films did not contain any h name="sbnd" />H groups. The surface film morphology was investigated by atomic force microscopy (AFM) and displayed a globular texture. The films were very smooth, with a maximum root mean square roughness, for example, of 14nm for a 0.96μm thick coating. The EIS data confirmed, as expected, that a 2.40μm Al2O3 layer ensures the best corrosion protection after 168h of immersion in the very acidic environment used. [Copyright &y& Elsevier]

• Optimization and analysis of the alkali activated mixtures were performed. • Laboratory and scale-up (pilot) productions of façade panels were conducted. • The durability behaviour of façade panels from both types of production was investigated. Novel prefabricated insulating façade panels were developed from construction and demolition waste (CDW) aggregates under the framework of the European H2020 project InnoWEE. These non-structural components, aimed at improving the thermal efficiency of existing buildings, consist of an insulating plate covered by a facing layer made of CDW aggregates bound with metakaolin, furnace slag and class F fly ash activated by a potassium silicate solution. The paper presents the design and assessment of the binder and panels for exterior use, taking into account mechanical performance, behaviour in the presence of water and durability issues. Testing was carried out on both laboratory prototypes and panels from the pilot industrial production. [ABSTRACT FROM AUTHOR]