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1.
Environ Res ; 212(Pt D): 113553, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35661730

RESUMO

In this work, a solar electrochemical-raceway pond reactor (SEC-RPR) is used to treat textile industrial wastewater by solar photoelectron-Fenton (SPEF) at pilot plant scale for the first time. The SEC-RPR is composed of an electrochemical filter press-cell coupled to RPR, where H2O2 is electro-generated. A complete study about experimental variables such as current, catalyst concentration, pollutant load or liquid depth is conducted based on methyl orange removal, mineralization and decolorization. Validation of the SPEF process using SEC-RPR reached more than 80% of mineralization, as well as the complete decolorization of the solution. The good performance of the SPEF treatment in the new SEC-RPR led to quick degradation kinetics, mainly due to the synergetic action of solar radiation and good distribution of H2O2 electrogenerated in the photoreactor. 100% Methyl Orange degradation was achieved after 150, 60, 45, 30 and 20 min of reaction time applying current density equal to 5, 10, 20, 40 and 60 mA cm-2, respectively. However, the increase of current density decreased the mineralization current efficiency. Up to 10 aromatics intermediates and 5 short-chain carboxylic acids were identified by LC-MS and HPLC analysis and a reaction pathway for MO mineralization by SPEF is proposed. This study represents an essential preliminary step towards the development of the first SEC-RPR at demo scale.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Oxirredução
2.
Biomedicines ; 10(1)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35052739

RESUMO

On Earth, humans are subjected to a gravitational force that has been an important determinant in human evolution and function. During spaceflight, astronauts are subjected to several hazards including a prolonged state of microgravity that induces a myriad of physiological adaptations leading to orthostatic intolerance. This review summarises all known cardiovascular diseases related to human spaceflight and focusses on the cardiovascular changes related to human spaceflight (in vivo) as well as cellular and molecular changes (in vitro). Upon entering microgravity, cephalad fluid shift occurs and increases the stroke volume (35-46%) and cardiac output (18-41%). Despite this increase, astronauts enter a state of hypovolemia (10-15% decrease in blood volume). The absence of orthostatic pressure and a decrease in arterial pressures reduces the workload of the heart and is believed to be the underlying mechanism for the development of cardiac atrophy in space. Cellular and molecular changes include altered cell shape and endothelial dysfunction through suppressed cellular proliferation as well as increased cell apoptosis and oxidative stress. Human spaceflight is associated with several cardiovascular risk factors. Through the use of microgravity platforms, multiple physiological changes can be studied and stimulate the development of appropriate tools and countermeasures for future human spaceflight missions in low Earth orbit and beyond.

3.
Chemosphere ; 247: 125813, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31951953

RESUMO

Heterogeneous electro-Fenton (HEF) is as an alternative to the conventional electro-Fenton (EF) process. HEF uses a solid phase catalyst, whereas EF employs a solubilized one. This implies that in HEF, material can be recovered through a simple separation process such as filtration or magnetic separation in HEF. HEF also has the advantage of not requires a previous pH adjustment, which facilitates working in a higher pH range. In this work, Fe, Cu and Fe/Cu bimetallic nanoparticles (Fe/Cu NPs) were synthesized, characterized and used for the degradation of Nafcillin (NAF). The effect of the adsorption and the anodic oxidation (AO-H2O2) process was tested to assess their influence on HEF. NAF adsorption did not exceed 24% of antibiotic removal and the AO-H2O2 process eliminated the total NAF after 240 min of electrolysis. Through the HEF process, the antibiotic was completely removed using Fe/Cu NPs after 7.0 min of electrolysis, while these NPs, mineralization reached 41% after 240 min. In this case, NAF degradation occurs mainly due to the generation of hydroxyl radicals in the BDD electrode, and the Fenton reaction with Fe and Cu NPs. The main organic intermediates produced during the degradation of NAF by HEF were identified allowing the proposal of degradation pathway. Finally, the antibiotic was also completely eliminated from a wastewater from slaughterhouse after 15 min of treatment by HEF and using Fe/Cu bimetallic NPs.


Assuntos
Cobre/química , Peróxido de Hidrogênio/química , Ferro/química , Nanopartículas Metálicas/química , Nafcilina/química , Antibacterianos/química , Catálise , Técnicas Eletroquímicas , Eletrólise/instrumentação , Eletrólise/métodos , Radical Hidroxila/química , Oxirredução , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
4.
Liberabit ; 22(1): 67-76, ene.-jun.2016. tab
Artigo em Espanhol | LILACS, LIPECS | ID: lil-790693

RESUMO

La presente investigación busca determinar el impacto de la saliencia de la mortalidad en motivos identitarios individuales y colectivos, como la autoestima, la eficacia, la pertenencia, la distintividad, la continuidad y el significado. Se hipotetizó que la conciencia de la propia muerte potenciaría, a nivel individual y colectivo, los motivos identitarios descritos. A través de un diseño experimental, se encontró que a nivel de identidad individual el grupo experimental (expuesto a la saliencia de la propia mortalidad) mostró puntuaciones marginalmente más elevadas que el grupo de control en los motivos de autoestima y de distintividad, y puntuaciones significativamente más elevadas en el motivo de continuidad. A nivel de identificación colectiva no se aprecia efecto alguno de la mortalidad sobre los motivos identitarios...


The present investigation intends to determine mortality salienceÆs impact on individual and collective identity, through identity motives such as self-esteem, efficacy, belongingness, distinctiveness, continuity and meaning. It was hypothesized that the awareness of oneÆs own death would boost the described identity motives at both individual and collective levels. Throughout an experimental design it was found that, for individual identity, the experimental group (exposed to mortality salience) showed marginally higher punctuations than the control group for the self-esteem and distinctiveness motives and significantly higher punctuations for the continuity motive. At the collective identity level mortality salience has no effect on the identity motives...


Assuntos
Atitude Frente a Morte , Isolamento Social , Autoimagem , Psicologia Social
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