Molybdenum-based nanostructured mixed oxides for sensing applications: Effect of the Mo oxide composition on the structure of sol-gel thin films

In this work, we report on the structural investigation by transmission electron microscopy of molybdenum-based mixed oxides for use as gas sensitive films. In particular, sol-gel thin films of molybdenum-titanium and molybdenum-tungsten oxides, deposited by spin coating on silicon substrates, have been analyzed by selected area electron diffraction, conventional, and high-resolution transmission electron microscopy. Our results show that the relative percentage of the molybdenum precursors used during the sol-gel deposition controls the morphology of the films, by modifying the size and the arrangements of the polycrystalline grains on the substrate

Pharmaceuticals from natural products: current trends

The use of products extracted from plants for medicinal purposes can be traced to the beginnings of civilization and up until the end of the nineteenth century natural products were the principal source of medicines. Since then their relative importance has oscillated according to the strategies of large pharmaceutical companies. Now that these strategies are changing, there are new opportunities for countries like Brazil, in which a large proportion of the world's biodiversity is located. There are, however, new circumstances that must be taken into consideration: material must be collected by groups which are formally authorized to do so and under the conditions of the Convention of Biological Diversity, the discovery process is being successively outsourced to smaller specialized firms and there is a growing integration with producers of cosmetics and phytomedicines.<br>O uso de produtos extraídos de plantas para fins medicinais pode ser tracejado aos inícios da civilização e até o fim do século XIX, os produtos naturais constituíram a principal fonte de medicamentos. Desde então, a importância relativa dos produtos naturais tem oscilado de acordo com as estratégias de grandes companhias farmacêuticas. Agora que estas estratégias vêm mudando, há novas oportunidades para países como o Brasil, no qual está localizada uma vasta proporção da biodiversidade mundial. Há, entretanto, novas circunstâncias que devem ser levadas em consideração: o material deve ser coletado por grupos que estão formalmente autorizados para tal, com a coleta sendo feita sob as condições da Convenção de Diversidade Biológica, o processo de descoberta está sendo sucessivamente terceirizado no sentido de firmas especializadas menores e há uma integração crescente como produtores de cosméticos e fitomedicamentos

Physical and gas sensing properties of MoO3-WO3 nanostructured oxides

9nonenoneA. Taurino; M. Catalano; R. Rella; P. Siciliano; K. Galatsis; Y.X. Li; W. Wlodarski; E. Comini; G. SberveglieriA., Taurino; M., Catalano; R., Rella; P., Siciliano; K., Galatsis; Y. X., Li; W., Wlodarski; Comini, Elisabetta; Sberveglieri, Giorgi

Investigation of MoO3-WO3 thin film microstructure for gas sensing applications

Abstract not available