Synthesis of self-organized nanostructured oxide for photocatalysis and photoelectrocatalysis application

Photocatalytic processes using self-organized TiO2 nanotubes semiconductor are considered together with the factors that affect the growth mechanism and formation of the nanotubes during the anodization of titanium. The chapter analyses the morphology of the nanotubes when they are modified with metals, oxides and wall decoration. Illustrated examples of the applications of TiO2 nanotubes in photocatalysis, photoelectrocatalysis, solar cells, semiconductors and biomedical areas are presented and the main characteristics required for these applications are highlighted.</p

Synthesis and characterization of self-organized oxide layer grown on ti-cu alloys system for CO 2 reduction

Ti-Cu alloys could be used as a substrate to produce photoelectrode pn-heterojunctions to increase copper stability and consequently to improve photoconversion of CO2. Cu–Ti–O films were grown by anodizing directly of Ti–x%at.Cu (x= 0.5, 5.5, 10 and 50) and after these alloys were submitted different kinds heat treatment (annealing or quenching) to compare a directly influence of presents phases in nanotubes alloy substrate after it preparation by voltaic arc melting following a annealed or rapid quenching as heat treatment. All films presented TiO2 and copper dioxides in its compositions. These electrodes showed higher absorbance in visible light, anodic current for less copper alloy cathodic current equiatomic composition and copper stability for all cases due cu atomic insertion inside TiO2 crystal lattice and sharing oxygen atomic. The cathodic current varied in function of Cu concentration in the alloy8974551COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES001The authors thank Coordenação de Aperfeiçoamento Pessoal de Nível Superior Brasil (CAPES) – Finance Code 001 for financial support. The authors acknowledge the support of LNNano - Brazilian Nanotechnology National Laboratory, CNPEM for SEM-FEG and XPS characterizatio

Photoelectrocatalytic oxidation of methyl orange on TiO2 nanotubular anode using a flow-cell

Methyl orange from water was removed by photocatalytic anodic oxidation method using a titanium dioxide array surface. The coating was prepared by anodising a titanium plate using NH4F as electrolyte followed by heat treatment to render a photocatalytic surface under UV light. SEM imaging showed that the array coating consisted of closely spaced 1 µm long, 0.1 µm internal diameter tubes perpendicular to the titanium plate. The aqueous solution of methyl orange was circulated through a rectangular channel flow cell containing the coated anode and the effect of electrolyte flow rate and applied potential on the oxidation rate and efficiency were evaluated. At higher mean linear flow rates, the efficiency of the oxidation process improved, indicating a mass transport controlled process. At more positive applied potentials the TiO2 structure deteriorated resulted in lower oxidation efficiency

Efficient degradation of solid yeast biomass from ethanol industry by Fenton and UV-Fenton processes applying multivariate analysis

<div><p>Abstract Organic agro-industrial residues have been successfully used as biosorbents and promoting new uses from agricultural wastes benefits the economy. However, the allocation of a solid waste biosorbent after the sorption of contaminants has limited their effective application on a large scale as an alternative treatment of water and wastewaters. One solution could be degradation to convert the biosorbent material and adsorbed organic contaminants into environmental friendly compounds suitable for discharge. This study used an experimental design to evaluate the Fenton degradation of yeast biomass (YB) from the alcohol industry as a potential biosorbent. The efficiency of degradation was monitored according to the degraded mass (DM) and total organic carbon (TOC) remaining in the solution. The ANOVA showed an error of 9.7% for the effects and the media of interaction for the employed model for DM. Conducting the experiments with the best-predicted conditions (60 min, 25 g of YB, pH 3, 8,000 mg L-1 H2O2 and 40 mg L-1 Fe2+) with 30 W UV irradiation resulted in a YB reduction of 72 ( 2% with a TOC of 30 ( 2%. This suggests that an advanced oxidative process is an alternative for degradation of a biosorbent after sorption.</p></div

Hereditary Angioedema with Normal C1 Inhibitor and F12 Mutations in 42 Brazilian Families.

Hereditary angioedema (HAE) with normal C1 inhibitor (C1-INH) is a rare condition with clinical features similar to those of HAE with C1-INH deficiency. Mutations in the F12 gene have been identified in subsets of patients with HAE with normal C1-INH, mostly within families of European descent.Our aim was to describe clinical characteristics observed in Brazilians from 42 families with HAE and F12 gene mutations (FXII-HAE), and to compare these findings with those from other populations.We evaluated a group of 195 individuals, which included 102 patients clinically diagnosed with FXII-HAE and their 93 asymptomatic relatives.Genetic analysis revealed that of the 195 subjects, 134 individuals (77.6% females) carried a pathogenic mutation in F12. The T328K substitution was found in 132 individuals, and the c.971_1018+24del72 deletion was found in 2 patients. The mean age at onset of symptoms in patients with FXII-HAE was 21.1 years. The most common symptoms were subcutaneous edema (85.8% of patients), abdominal pain attacks (69.7%), and upper airway edema (32.3%). Of male individuals carrying F12 mutations, 53.3% (16 of 30) were symptomatic. Compared with reports from Europe, fewer female patients (68.6%) reported an influence of estrogen on symptoms.Our study included a large number of patients with FXII-HAE, and, as the first such study conducted in a South American population, it highlighted significant differences between this and other study populations. The high number of symptomatic males and patients with estrogen-independent FXII-HAE found here suggests that male sex and the absence of a hormonal influence should not discourage clinicians from searching for F12 mutations in cases of HAE with normal C1-INH