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2.
Ecotoxicol Environ Saf ; 130: 81-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27085001

RESUMO

Indium has numerous applications in different industrial sectors and is not an abundant element. Therefore appropriate technology to recover this element from various process wastes is needed. This research reports high adsorption capacity of multiwalled carbon nanotubes (MWCNT) for In(III). The effects of pH, kinetics, isotherms and adsorption mechanism of MWCNT on In(III) adsorption were investigated and discussed in detail. The pH increases improves the adsorption capacity for In(III). The Langmuir adsorption model is the best fit with the experimental data. For the kinetic study, the adsorption onto MWCNT could be fitted to pseudo second-order. The adsorption of indium(III) can be described to a mechanism which consists of a film diffusion controlled process. Metal desorption can be achieved with acidic solutions.


Assuntos
Índio/química , Nanotubos de Carbono/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Soluções , Temperatura , Purificação da Água/métodos
3.
Waste Manag ; 32(3): 550-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22119052

RESUMO

This paper describes an industrial process for stabilising sewage sludge (SS) with lime and evaluates the viability of the stabilised product, denominated Neutral, as a raw material for the cement industry. Lime not only stabilised the sludge, raised the temperature of the mix to 80-100°C, furthering water evaporation, portlandite formation and the partial oxidation of the organic matter present in the sludge. Process mass and energy balances were determined. Neutral, a white powder consisting of portlandite (49.8%), calcite (16.6%), inorganic oxides (13.4%) and organic matter and moisture (20.2%), proved to be technologically apt for inclusion as a component in cement raw mixes. In this study, it was used instead of limestone in raw mixes clinkerised at 1400, 1450 and 1500°C. These raw meals exhibited greater reactivity at high temperatures than the limestone product and their calcination at 1500°C yielded clinker containing over 75% calcium silicates, the key phases in Portland clinker. Finally, the two types of raw meal (Neutral and limestone) were observed to exhibit similar mineralogy and crystal size and distribution.


Assuntos
Compostos de Cálcio/química , Materiais de Construção , Óxidos/química , Reciclagem , Esgotos , Hidróxido de Cálcio/química , Projetos Piloto
5.
Neurology ; 74(5): 357-65, 2010 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-20054008

RESUMO

BACKGROUND: It is uncertain whether neurogenesis occurs in humans after stroke. We studied the morphologic changes that occurred in the subventricular zone (SVZ) in patients who died following an acute ischemic stroke. METHODS: We examined coronal brain slices from patients who died after a first-ever cerebral nonlacunar infarction in the middle cerebral artery territory. We evaluated the morphologic changes in the ipsilateral and contralateral SVZ by light and electron microscopy. Using immunochemistry with Ki-67 and PCNA, we detected cell proliferation. We used Tuj-1 for immature neurons and PSA-NCAM for migrating cells. RESULTS: The study included 7 patients with a mean age of 82 +/- 5 (mean +/- SD) years; 4 were men. They died a mean of 10 +/- 5 days after the ischemic stroke. Brain samples were obtained a mean of 4 +/- 2 hours after death. In comparison with the contralateral SVZ, the following changes were observed in the ipsilateral SVZ: an increase in the width of the gap and ribbon layers, as well as in the cell density of the ribbon layer, an enlargement of the cytoplasmic volume of astrocytes, and an increase of Ki-67-positive cells. In the ipsilateral SVZ, mitoses and cells that stained for either Tuj-1 or PSA-NCAM markers were observed more frequently than in the contralateral SVZ. CONCLUSION: We found unequivocal evidence of active cell proliferation in the ipsilateral subventricular zone following an acute ischemic stroke in our patients.


Assuntos
Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/fisiopatologia , Lateralidade Funcional/fisiologia , Neurogênese/fisiologia , Acidente Vascular Cerebral/patologia , Células-Tronco Adultas/fisiologia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Isquemia Encefálica/complicações , Proliferação de Células , Ventrículos Cerebrais/ultraestrutura , Feminino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Microscopia Eletrônica de Transmissão/métodos , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Ácidos Siálicos/metabolismo , Acidente Vascular Cerebral/etiologia
7.
Eur J Neurol ; 15(10): 1085-90, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18717722

RESUMO

BACKGROUND AND PURPOSE: We performed an observational study that compared baseline and subsequent blood pressure (BP) measurements and its association with haematoma enlargement (HE) in patients with intracerebral haemorrhage (ICH). METHODS: We prospectively studied consecutive patients with supratentorial spontaneous ICH within the first 6 h after the onset of symptoms. HE was defined as an increase >or=33% in the volume of haematoma on the CT obtained 24-48 h after the onset of symptoms as compared with the CT at admission. We recorded systolic BP (SBP), diastolic BP (DBP) and mean BP (MBP) at admission and at 6, 12, 18 and 24 h after onset; the maximum SBP, DBP and MBP during the study period; the maximum SBP and DBP within intervals; the mean of all BP readings; administration of antihypertensive agents. RESULTS: We studied 60 patients whose mean age was 72.1 +/- 11.3 years. HE was observed in 27 (45%) patients. No statistically significant differences were observed in any of the analyses that compared BP parameters between the HE and non-HE groups (two-way anova). CONCLUSIONS: In an exploratory analysis, we did not find an association between BP and HE within the first 24 h after an acute ICH.


Assuntos
Pressão Sanguínea/fisiologia , Hemorragia Cerebral/fisiopatologia , Circulação Cerebrovascular/fisiologia , Hematoma/fisiopatologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Progressão da Doença , Feminino , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Homeostase , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia Computadorizada por Raios X
8.
Sci Total Environ ; 302(1-3): 247-51, 2003 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-12526913

RESUMO

A historic building stone, Baumberger sandstone, was exposed to gaseous SO(2) under dry and wet surface conditions in an atmospheric test chamber. The extent of salt formation resulting from the exposure to pollutant gases as well as the variations in mineralogical composition were studied based on petrological thin sections. Results reveal that the salts are formed only over the surface of the sample. The thickness of the formed salt crusts is determined. Calcite dissolution as well as porosity decreases are due to gypsum formation.

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