A Summary of Methods for Fire Tests of Roof Coverings

AbstractThe testing method about the fire performance of roof covering and materials has not been put into operation in China. This article focuses on two main international testing about fire performance of roof covering and materials, comparing the difference between the two test methods

Synthesis and Properties of Gold Nanoparticle Arrays Self-Organized on Surface-Deposited Lysozyme Amyloid Scaffolds

In this study, amyloid fibers prepared from hen egg white lysozyme (HEWL) are specifically mediating the assembly of citrate-capped gold nanoparticles, on glass and silicon substrates. The organization of nanoparticles is investigated for nanoparticle diameters of 5, 15, and 25 nm, using variable deposition times, and under a range of pH, salt, citric acid and nanoparticle concentrations. The observed periodic self-organization of nanoparticles is mainly influenced by the interparticle interactions rather than by the spacing of binding groups at the surface of the amyloid fiber template. For a fixed ionic strength of 2.3 mM and particle concentration, the interparticle distance increases with the nanoparticle diameter in agreement with the values predicted by the Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory. UV–visible spectroscopy measurements show a red shift of the 520 nm plasmon absorption peak associated with spherical gold nanoparticles up to 650 nm upon aggregation or decrease in the interparticle distance. Such protein templates deposited on technologically relevant surfaces allow the self-assembly of inorganic nanoparticle arrays with functional optoelectronic properties

Bottom-Up Mechanical Nanometrology of Granular Ag Nanoparticles Thin Films

Ultrathin metal nanoparticles coatings, synthesized by gas-phase deposition, are emerging as go-to materials in a variety of fields ranging from pathogens control and sensing to energy storage. Predicting their morphology and mechanical properties beyond a trial-and-error approach is a crucial issue limiting their exploitation in real-life applications. The morphology and mechanical properties of Ag nanoparticle ultrathin films, synthesized by supersonic cluster beam deposition, are here assessed adopting a bottom-up, multitechnique approach. A virtual film model is proposed merging high resolution scanning transmission electron microscopy, supersonic cluster beam dynamics, and molecular dynamics simulations. The model is validated against mechanical nanometrology measurements and is readily extendable to metals other than Ag. The virtual film is shown to be a flexible and reliable predictive tool to access morphology-dependent properties such as mesoscale gas-dynamics and elasticity of ultrathin films synthesized by gas-phase deposition

Bottom-Up Mechanical Nanometrology of Granular Ag Nanoparticles Thin Films

Ultrathin metal nanoparticles coatings, synthesized by gas-phase deposition, are emerging as go-to materials in a variety of fields ranging from pathogens control and sensing to energy storage. Predicting their morphology and mechanical properties beyond a trial-and-error approach is a crucial issue limiting their exploitation in real-life applications. The morphology and mechanical properties of Ag nanoparticle ultrathin films, synthesized by supersonic cluster beam deposition, are here assessed adopting a bottom-up, multitechnique approach. A virtual film model is proposed merging high resolution scanning transmission electron microscopy, supersonic cluster beam dynamics, and molecular dynamics simulations. The model is validated against mechanical nanometrology measurements and is readily extendable to metals other than Ag. The virtual film is shown to be a flexible and reliable predictive tool to access morphology-dependent properties such as mesoscale gas-dynamics and elasticity of ultrathin films synthesized by gas-phase deposition