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Abstract The paper presents the results of an experimental activity aimed at producing and characterizing a nano-encapsulated PEG600 (PCMs) into a silica shell. The nano-encapsulation was meant to be useful to improve the material's suitability to integration in building components. The (300±15)nm nanoparticles that were produced underwent a full characterization of their thermal performances. An enthalpy of fusion as high as 66.24 kJ/kg, in a tight melting temperature range (20–21°C) was obtained, making the material suitable for thermal energy storage in buildings. In order to demonstrate the benefits of such as this technology on the reduction of heating and cooling demand of buildings, a concentration of 50% in weight of nanoparticles was, then, embedded into a gypsum plasterboard and used for all indoor plastered surfaces of a reference residential buildings. A saving of respectively up to 4.3% and up to 1.1% of heating and cooling energy demand was predicted in comparison to the ones of a building without PCM. Finally, the material underwent a full toxicological characterization exposing human alveolar basal epithelial cells to nanoparticles. The results showed that there were no toxic effects on cell morphology. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanoparticles (TiO 2 NPs), in the two crystalline forms, rutile and anatase, have been widely used in many industrial fields, especially in cosmetics. Therefore, a lot of details about their safety issues have been discussed by the scientific community. Many studies have led to a general agreement about TiO 2 NPs toxicity, in particular for anatase form, but no mechanism details have been proved yet. In this study, data confirm the different toxic potential of rutile and anatase TiO 2 NPs in two cell lines up to 5 nM nanoparticles concentration. Moreover, we evaluated the role of titanium ions released by TiO 2 NPs in different conditions, at pH = 4.5 (the typical lysosomal compartment pH) and at pH = 5.5 (the skin physiological pH) in conditions of darkness and light, to mimic the dermal exposure of cosmetics. Anatase nanoparticles were proner to degradation both in the acidic conditions and at skin pH. Our study demonstrates that pH and sunlight are dominant factors to induce oxidative stress, TiO 2 NPs degradation and toxicity effects. [ABSTRACT FROM AUTHOR]

Early detection and diagnosis of diseases is a critical issue. A colorimetric “point-of-care” device – based on the principle of electrochromism – is proposed here for the precocious diagnosis of cystic fibrosis, especially in resource-limited environments, developing countries and ambulatory contests. We designed a complete device architecture to detect sodium chloride in a small amount of human sweat (3 μL), conceived in order to complete the steps of sample preparation and disease diagnosis. The device, as an alternative route for conductivimetric analysis, measures the amount of sodium chloride in a sample of sweat exploiting the electrochromic properties of tungsten oxide. In our case, sodium sweat promotes an oxide blue coloration depending on the cation concentration. Indeed the device shows an effective transmittance modulation when sodium cations exceed the physiological threshold. optical modulations of 48%, 35%, 15%, 7% were observed, at 555 nm, for sodium concentrations of 120 mmol/L, 90 mmol/L, 60 mmol/L, and 30 mmol/L, respectively. In the reported experimental investigations, both human and artificial sweat were employed, with strictly comparable results. [ABSTRACT FROM AUTHOR]

Ring-closing metathesis (RCM) has been shown to be a viable tool to incorporate fluoride and trifluoromethyl substituents in (hetero)cyclic ring systems. 2-Fluoroacrylamides were cyclized to the corresponding lactams, and trifluoromethyl-substituted olefins were cyclized to yield trifluoromethylated cyclopentenes, pyrrolines and a dihydrofuran derivative. [Copyright &y& Elsevier]

Abstract A significant interest in sustainable sound absorbing materials is fostering many researches on the use of recycled and vegetable products, that normally would have been sent to wastes, as compounds to obtain new building materials. One key issue when preparing new composite materials is the choice of the binder, which, in many cases, may significantly reduce the sustainability of the product by introducing synthetic and plastic elements. In the present paper olive tree pruning wastes bounded with chitosan are investigated to obtain sound absorbing materials. Experimental results showed that absorption coefficients as high as 0.9 can be obtained above 1 kHz using a 50 mm sample, and that a very good agreement with the phenomenological model for sound absorption through a rigid frame is obtained, suggesting that the model can be conveniently used to further improve the sound absorption characteristics of the samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • m-SPL techniques allow the patterning at the nanoscale with unprecedented precision. • Nanoindentation is the easiest m-SPL, permitting the realization of nanoholes array. • AFM Plowing lithographies allow for patterning in contact and semicontact modes. • Static and Dynamic Plowing lithography stands for advanced m-SPL techniques. • Coupled m-SPL enhances the patterning capability and the properties of nanostructures. In recent years, the scientific community's interest in nanoscience and nanotechnology stems from the increasing capability to manipulate matter at the nanoscale. Nanotechnology development is closely linked to fabricating and characterizing structures below 100 nm, driven by technological advancements enabling their in-depth analysis. Up to now, several top-down and bottom-up nanofabrication approaches have been developed to realize a plethora of nanostructures. Although effective, these methods have many drawbacks like high costs and limitations in feature size. In this scenario, Scanning Probe-based Lithography (SPL) emerges as a very promising alternative to conventional nanofabrication techniques, overcoming their main method limitations with versatility, flexibility, low cost, and nanoscale resolution. This review focuses on mechanical Scanning Probe-based Lithography (m-SPL), tracing its evolution from inception to recent advances. Different m-SPL methods, such as Nanoindentation, Static and Dynamic Plowing lithography, Nanomilling, and their variants are discussed in-depth, emphasizing their advantages and drawbacks, and highlighting their application. Moreover, this review explores the effects of combining m-SPL with other energy sources, such as heat and electric energy, and outlines future perspectives in the field. Overall, m-SPL stands out as a promising avenue in nanofabrication, offering sub-nanometer resolution and diverse material manipulation capabilities. [ABSTRACT FROM AUTHOR]