Carbon nanotubes as catalysts for wet peroxide oxidation: The effect of surface chemistry

Three magnetic carbon nanotube (CNT) samples, named A30 (N-doped), E30 (undoped) and E10A20 (selectively N-doped), synthesized by catalytic chemical vapor deposition, were modified by introducing oxygenated surface groups (oxidation with HNO3, samples CNT-N), and by heat treatment at 800 °C for the removal of surface functionalities (samples CNT-HT). Both treatments lead to higher specific surface areas. The acid treatment results in more acidic surfaces, with higher amounts of oxygenated species being introduced on Ndoped surfaces. Heat-treated samples are less hydrophilic than those treated with nitric acid, heat treatment leading to neutral or basic surfaces, only N-quaternary and N-pyridinic species being found by XPS on N-doped surfaces. These materials were tested in the catalytic wet peroxide oxidation (CWPO) of highly concentrated 4-nitrophenol solutions (4-NP, 5 g L−1) at atmospheric pressure, T=50 °C and pH=3, using a catalyst load of 2.5 g L−1 and the stoichiometric amount of H2O2 needed for the complete mineralization of 4-NP. The high temperature treatment enhanced significantly the activity of the CNTs towards CWPO, evaluated in terms of 4-NP and total organic carbon conversion, due to the increased hydrophobicity of their surface. In particular, E30HT and E10A20HT were able to remove ca. 100% of 4-NP after 8 h of operation. On the other hand, by treating the CNTs with HNO3, the activity of the less hydrophilic samples decreased upon increasing the concentration of surface oxygen-containing functionalities, whilst the reactivity generated inside the opened nanotubes improved the activity of the highly hydrophilic A30 N.This work is a result of project “AIProcMat@N2020 - Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020”, with the reference NORTE-01-0145-FEDER-000006, supported by NORTE 2020, under the Portugal 2020 Partnership Agreement, through the ERDF and of Project Associate Laboratory LSRE-LCM - UID/EQU/50020/2019 - funded by national funds through FCT/MCTES (PIDDAC). M. Martín Martínez acknowledges the postdoc grant 2017-T2/AMB-5668 from Comunidad de Madrid, Programme “Atracción de talento investigador”. B. Machado acknowledges the exploratory project under FCT Investigator Programme (ref. IF/00301/ 2015) with the financial support of FCT/MCTES through national funds (PIDDAC). S. Morales Torres acknowledges the financial support from University of Granada (Reincorporación Plan Propio).info:eu-repo/semantics/publishedVersio

Carbon based materials for photocatalytic solar applications in water treatment

When dealing with chemical wastewater treatments one depends on the addition of auxiliary oxidants, which may include molecular oxygen, ozone, and hydrogen peroxide, working on their own, or activated by means of a catalyst or photocatalyst. Typical solutions are the thermal processes at elevated temperatures and pressures. Alternatively, it is possible to use heterogeneous photocatalysis at room temperature and atmospheric pressure. With the development of new carbon allotropes a whole range of advanced oxidation processes, traditionally based on the action of the HO● radical, can be explored using carbon materials as common denominator

Hydrophobicity in catalysts for wet peroxide oxidation

Organic pollutants, such as phenol and its derivatives, are commonly present in wastewaters from several industries. These compounds are difficult to remove by conventional biological processes, mainly when present at high concentrations (1-10 g L-1)1. Catalytic wet peroxide oxidation (CWPO) is regarded as a potential solution for the treatment of aqueous effluents containing this type of recalcitrant, toxic and non-biodegradable compounds

Carbon nanotubes as catalysts for wet peroxide oxidation: structure-reactivity relationships

Magnetic neat and N-doped carbon nanotubes with different properties have been synthesized by chemical vapour deposiüon and tested in the catalytic wet peroxide oxidation of 4-nitrophenol solutions (5 g L') at relatively mild operating conditions (atmospheric pressure, T = 50 °C, pH = 3)~using a catalyst load = 2.5 g L-' and [H202]o = 17.8 g L-1. The results demonstrate that the catalyst hydrophobicity/ hydrophilicity is a detenninant property in the CWPO reaction, since it affects the rate ofH202 decomposition. The controlled formation ofreactive radicais (HO* and HOO*) at hydrophobic surfaces avoids the formation of non-reactive species (02 and H20), increasing

Comunicação terapêutica na interação profissional de saúde e hipertenso na estratégia saúde da família

Objetivo: Analisar a comunicação terapêutica na interação profissional de saúde e hipertenso na Estratégia Saúde da Família.Métodos: Estudo descritivo com abordagem qualitativa. A amostra constituiu-se de 14 hipertensos e dois profissionais da ESF em um município do Estado do Ceará, Brasil, em 2016. Na coleta de dados, utilizou-se um checklist para observação sistemática não participante, contendo as estratégias de comunicação terapêutica: expressão, clarificação, validação e um diário de campo, sendo tratados pela análise de conteúdo.Resultados: Verificou-se que os profissionais da ESF não utilizam, de forma adequada, a comunicação terapêutica, reconhecendo a necessidade de investimento nesse dispositivo que atua como ponte de acesso aos usuários, potencializa as práticas assistenciais e abre caminhos que instrumentaliza as relações interpessoais.Conclusões: Desvelou-se que as estratégias de comunicação terapêutica são pouco exploradas pelos profissionais de saúde, necessitando, portanto, desenvolver habilidades para empregá-las, adequadamente, no cuidado ao hipertenso.Palavras-chave: Comunicação. Terapêutica. Relações interpessoais. Hipertensão. Atenção primária à saúde.

Accuracy of faecal calprotectin and neutrophil Gelatinase B-associated Lipocalin in evaluating subclinical inflammation in UlceRaTIVE colitis-the ACERTIVE study

Background and Aims: Mucosal healing and histological remission are different targets for patients with ulcerative colitis, but both rely on an invasive endoscopic procedure. This study aimed to assess faecal calprotectin and neutrophil gelatinase B-associated lipocalin as biomarkers for disease activity in asymptomatic ulcerative colitis patients. Methods: This was a multicentric cross-sectional study including 371 patients, who were classified according to their endoscopic and histological scores. These results were evaluated alongside the faecal levels of both biomarkers. Results: Macroscopic lesions [i.e. endoscopic Mayo score >= 1] were present in 28% of the patients, and 9% had active disease according to fht Ulcerative Colitis Endoscopic Index of Severity. Moreover, 21% presented with histological inflammation according to the Geboes index, whereas 15% and 5% presented with focal and diffuse basal plasmacytosis, respectively. The faecal levels of calprotectin and neutrophil gelatinase B-associated lipocalin were statistically higher for patients with endoscopic lesions and histological activity. A receiver operating characteristic-based analysis revealed that both biomarkers were able to indicate mucosal healing and histological remission with an acceptable probability, and cut-off levels of 150-250 mu g/g for faecal calprotectin and 12 mu g/g for neutrophil gelatinase B-associated lipocalin were proposed. Conclusions: Faecal calprotectin and neutrophil gelatinase B-associated lipocalin levels are a valuable addition for assessment of disease activity in asymptomatic ulcerative colitis patients. Biological levels of the analysed biomarkers below the proposed thresholds can rule out the presence of macroscopic and microscopic lesions with a probability of 75-93%. However, caution should be applied whenever interpreting positive results, as these biomarkers present consistently low positive predictive values.Portuguese IBD Group [GEDII - Grupo de Estudo da Doenca Inflamatcria Intestinal]info:eu-repo/semantics/publishedVersio

Erratum to: The study of cardiovascular risk in adolescents – ERICA: rationale, design and sample characteristics of a national survey examining cardiovascular risk factor profile in Brazilian adolescents

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