Corrole-silica hybrid particles: synthesis and effects on singlet oxygen generation

The present study describes the first example of hybrid particles composed of amorphous silica and corrole. The hybrid particles were obtained by covalent linking of the gallium(III)(pyridine) complex of 5,10,15-tris(pentafluorophenyl) corrole (GaPFC) at the surface of functionalized silica spheres. The functionalization step was achieved by a nucleophilic substitution reaction between corrole and 3-aminopropyltriethoxysilane previously grafted at the silica surfaces. The hybrids were morphologically and chemically characterized and the results have confirmed covalent linkages between corrole molecules and the silica particles. Preliminary studies on the capacity of corrole and hybrid particles to generate singlet oxygen was evaluated by a chemical method in which 1,3-diphenylisobenzofuran was used to trap singlet oxygen. The new corrole-silica hybrid particles have shown lower efficiency to generate singlet oxygen as compared to the pure corrole precursor. This effect was interpreted as a consequence of interparticle interactions mediated by the corrole molecules grafted at the silica surfaces that result in their clustering. Taken together, these findings demonstrate that despite lower efficiency in terms of singlet oxygen generation, the hybrid materials offer an alternative route to develop new platforms with potential for photodynamic therapy

Optical and Electronic NOx Sensors for Applications in Mechatronics

Current production and emerging NOx sensors based on optical and nanomaterials technologies are reviewed. In view of their potential applications in mechatronics, we compared the performance of: i) Quantum cascade lasers (QCL) based photoacoustic (PA) systems; ii) gold nanoparticles as catalytically active materials in field-effect transistor (FET) sensors, and iii) functionalized III-V semiconductor based devices. QCL-based PA sensors for NOx show a detection limit in the sub part-per-million range and are characterized by high selectivity and compact set-up. Electrochemically synthesized gold-nanoparticle FET sensors are able to monitor NOx in a concentration range from 50 to 200 parts per million and are suitable for miniaturization. Porphyrin-functionalized III-V semiconductor materials can be used for the fabrication of a reliable NOx sensor platform characterized by high conductivity, corrosion resistance, and strong surface state coupling

SPECTROELECTROCHEMICAL AND X-RAY PHOTOELECTRON SPECTROSCOPIC STUDIES OF PORPHYRINS AND RELATED COMPOUNDS.

Abstract not availabl

A Study on the Comparative Effects of Keyswitch Design of Desktop and Notebook Keyboards Related to Key Stiffness and Typing Force

Interest in the ergonomics of keyboard design and mechanism has become widespread due to the increasing popularity of personal computers. The increased use of keyboard typing has generated several studies addressing the issue of key force relevant to repetitive disorders and user comfort. However, previous studies on key stiffness, typing force, and user comfort employed keyboards of the desktop class, and to the author\u27s knowledge no studies have been published on the key force characteristics of notebook computer keyboards. Also lacking are studies examining the forces exerted by subjects while typing on notebook keyboards and a comparative analysis of notebook and desktop keyboards. The research performed in this thesis will address this research void and provide key and fingertip force characteristics of notebook keyboards together with a comparison of notebook and desktop keyboards. Since notebooks are becoming increasingly popular, studies on the biomechanical and psychosocial characteristics of the notebook keyboard would be of significant use when designing for user comfort and health considerations