Synthesis and properties of Co-doped titanate nanotubes and their optical sensitization with methylene blue

Here we report on a novel chemical route to synthesize homogenous cobalt doped titanate nanotubes (CoTNT), using an amorphous Co-doped precursor. The influence of the synthesis temperature, autoclave dwell time and metal doping on the structural and microstructural as well as on the optical properties of the synthesized titanate nanotubes is studied and discussed. The optical band gaps of the CoTNT samples are red shifted in comparison with the values determined for the undoped samples, such red shifts bringing the absorption edge of the CoTNT samples into the visible region. CoTNT materials also demonstrate particular high adsorption ability for methylene blue, the amount of the adsorbed dye being higher than the one predictable for a monolayer formation. This suggests the possibility of intercalation of the dye molecule between the TiO6 layers of the TNT structure. It is also shown that the methylene blue sensitized Co-doped nanostructures are highly stable under UV radiation and present a strong and broad absorption in the visible region.Comment: 31 pages, 3 tables, 7 figure

TIBIAL ROTATIONS DURING STEP UP EXERCISE DO NOT CHANGE KNEE EXTENSOR ACTIVITY IN THE PATELLOFEMORAL PAIN SYNDROME

The purpose of this study was to compare the electromyographic activity of vastus medialis (VM) and vastus lateralis (VL) muscles during step up exercises at different tibial rotations, between individuals with and without patellofemoral pain syndrome. The electromyographic activity of the VM and VL muscles during step up exercises was evaluated in three tibial rotations: without rotation, medial and lateral rotation. Thirteen patients with patellofemoral pain syndrome and 16 control subjects performed this exercise three times. The results showed a significant lower electromyographic activity of VM muscle in both groups, compared to the electromyographic activity of VL muscle (

Aplicação do bagaço de cana como biomassa energética e do sulfato de amônia como fonte de nitrogênio para síntese de celulases por Lentinula edodes.

Editores técnicos: Marcílio José Thomazini, Elenice Fritzsons, Patrícia Raquel Silva, Guilherme Schnell e Schuhli, Denise Jeton Cardoso, Luziane Franciscon. EVINCI. Resumos

Temperature dependence of the coercive field in single-domain particle systems

The magnetic properties of Cu97Co3 and Cu90Co10 granular alloys were measured over a wide temperature range (2 to 300K). The measurements show an unusual temperature dependence of the coercive field. A generalized model is proposed and explains well the experimental behavior over a wide temperature range. The coexistence of blocked and unblocked particles for a given temperature rises difficulties that are solved here by introducing a temperature dependent blocking temperature. An empirical factor gamma arise from the model and is directly related to the particle interactions. The proposed generalized model describes well the experimental results and can be applied to other single-domain particle system.Comment: 7 pages, 8 figures, revised version, accepted to Physical Review B on 29/04/200

Monitoring strategies for “Ponta da Ferraria e Pico das Camarinhas” geosite (S. Miguel Island, Azores)

This paper presents an ongoing work that is being developed under the scope of a master thesis. “Ponta da Ferraria e Pico das Camarinhas” is a protected area and a geosite with high geological relevance in S. Miguel Island, Azores archipelago, Portugal. Because of its importance for the Azores Geopark geoconservation strategy, a monitoring work has been under development during the last year in order to assure that the main geological features of the geosite are preserved, even considering its present use. Among the many geological features of the geosite the littoral cone (or pseudocrater) is the most endangered due to its uniqueness and high vulnerability. The monitoring strategy also intends to assess how visitors evaluate the interpretative panel located in the geosite based on visitors’ opinions. The number of visitors is being determined by direct counting and the visitors’ profile is being outlined based on data obtained with short questionnaires