Nanoparticles and Nanolayers In Commercial Applications

This paper presents particulate and layered materials used in industry with at least one dimension under 500 nm. The objective is to bring to the attention of researchers areas of investigation where new properties and phenomena may manifest. The most relevant materials are natural and synthetic platelets and spherical and coated silica particles.     

Nano-Particles by Wet Chemical Processing in Commercial Applications

Nano-sized materials produced by wet chemical processing have a wide range of industrial applications. For example, a solution of monodisperse SiO₂-particles for single-layer anti-reflection coating on glass was developed. Although being porous, the anti-reflection coating shows excellent mechanical stability which is sufficient for commercial applications. The coating sol is used to produce cover glass with high transmission for solar energy systems, e.g. photovoltaic modules.Nano-sized materials made by sol–gel processes are not limited to niche applications. Inorganic metal oxide coatings on thin mica platelets are the basis for pearl lustre pigments. The inorganic layers, consisting of titanium dioxide or iron oxides, are obtained by a wet chemical procedure. The well-defined layer thickness, varying from 50 to 300 nm, determines the optical properties of the pearlescent pigment. By using synthetic SiO₂ platelets instead of natural mica, impressive angle-dependant colour effects can be achieved. Synthetic SiO₂ platelets are also produced by a sol–gel coating technique.Special spherical silica particles made by a wet chemical processing are used in cosmetic applications. The size distribution determines the skin feeling of the formulation. In addition, specific colour or anti-wrinkle effects can be achieved.     

Synthesis,characterization, and field‐effect transistor performance of poly[2,6‐bis(3‐tridecanoxythiophen‐2‐yl)benzo[1,2‐b;4,5‐b′]dithiophene]

A new copolymer of benzo[1,2‐b:4,5‐b′]dithiophene and 3,3′‐bis(tridecanoxy)‐5,5′‐bithiophene was synthesized through Stille copolymerization. The bis‐(3‐alkoxythiophene) monomer was synthesized through a silver fluoride mediated, palladium‐catalyzed cross‐coupling, in which bromide functional groups were preserved instead of consumed. The copolymer has been characterized and applied in field‐effect transistors, giving a hole mobility of 2 × 10^?3 cm²/Vs and an on/off ratio >10⁶, with negligible hysteresis, on standard silicon substrates. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1973–1978, 2010     

Status report on theGALLEX experiment

Summary The GALLEX collaboration is performing an experiment for the detection of neutrinos coming principally from the p-p fusion reaction in the Sun, via the reaction ν_e+⁷¹Ga→⁷¹Ge+e⁻. The experiment is running in the Gran Sasso Underground Laboratory of INFN, using as a target 30.3 tons of gallium in the form of 8.13 molar aqueous GaCl₃ solution. A report is given of the status of GALLEX after the end of the operations devoted to the removal from the solution of the cosmogenically formed Ge isotopes, completed in the middle of 1991. The experiment is now collecting data on solar neutrinos and the data analysis is in progress. Preliminary results concerning the first year of measurement are presented. Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990.     

Phosphorus-Nitrogen Compounds as Complex Ligands

Abstract

Amino(imino)phosphanes(σ²-phosphazenes) of the type N[sbnd]P[dbnd]N- are useful complex ligands.