Icpoes
Mostrando 1-12 de 190 artigos, teses e dissertações.
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1. AVALIAÇÃO DE METAIS POTENCIALMENTE TÓXICOS EM CHORUME PROVENIENTE DE ÁREA DE DEPOSIÇÃO DE RESÍDUOS SÓLIDOS EM BELÉM - PARÁ
The formation of solid waste is a global challenge regarding environmental preservation. Due to the lifestyle of modern society, which aims to improve practicality, new products are constantly being released in the market and increasing the formation of waste. The decomposition of waste from various origins produces a dark liquid named leachate, which presen
Química Nova. Publicado em: 2022
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2. Atomic Absorption Spectrometry as an Alternative to Determine the Presence of Gold Nanoparticles on or in Silica Matrix
Two different gold-silica-based nanomaterials were prepared: (i) silica-supported gold nanoparticles (AuNP/SiO2); and (ii) gold-silica core-shell nanoparticles (AuNP@SiO2). Three strategies for sample treatment (S), consisting in acid treatments, were employed: (S1) HNO3; (S2) HNO3 + HCl; and (S3) HF + HNO3 + HCl, applying microwave oven digestion for S2 and
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Preparation of SAPO-34-Based Catalyst for Conversion of Fructose to 5-Hydroxymethylfurfural
Solid acid-catalyzed dehydration of fructose to produce 5-hydroxymethylfurfural (5-HMF) has been a hotspot in biomass conversion research in recent years. In this study, a novel SAPO-34-based catalyst was prepared by consecutive steps of titanium doping, sulfuric acid impregnation, and sulfonic acid functionalization. Characterization of the catalyst with X-
J. Braz. Chem. Soc.. Publicado em: 2021-08
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4. Selective Entrapment of Pb2+ from Fresh Thunbergia laurifolia Leaves Extract and Thunbergia laurifolia Tea Extract
The leaves of Thunbergia laurifolia and its tea were extracted by water. The abilities to chelate heavy metal ions of the extracts were studied by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and atomic absorption spectroscopy (AAS). The results showed that the extracts exhibited high selectivity for Pb2+ chelation via a favourable-sele
J. Braz. Chem. Soc.. Publicado em: 2020-03
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5. SYNTHESIS OF MESOPOROUS γ-ALUMINA AND ITS CATALYTIC PERFORMANCE IN DICHLOROPROPANOL CYCLIZATION
This paper discusses the synthesis and resulting catalytic performance of mesoporous alumina using aluminum isopropoxide as the aluminum source, and synthesized organosiloxane KH560-540 as template. The effects of the hydrothermal conditions, as well as the amount of templating agent at pH values of 5-9 on the structure of the synthesized mesoporous alumina
Quím. Nova. Publicado em: 21/10/2019
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6. Adding value to polystyrene waste by chemically transforming it into sulfonated polystyrene
ABSTRACT Polystyrene (PS), one of the most used polymers in everyday life, has a low recycling rate due to its inexpensive virgin resin. In order to make polystyrene waste (WPS) recycling advantageous, it is possible to change it chemically, introducing heteroatoms in the polymer chain thus transforming the waste into a material with more added value. In thi
Matéria (Rio J.). Publicado em: 16/09/2019
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7. Levels of Chromium, Copper, Iron, Magnesium, Manganese, Selenium, Zinc, Cadmium, Lead and Aluminium of honey varieties produced in Turkey
Abstract Honey is a natural animal product. The elemental composition of honey varies greatly depending on the source of nectar, honeydew, pollen and environmental conditions. The aim of the present study was to determine the levels of chromium (Cr), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), selenium (Se), zinc (Zn), cadmium (Cd), lead (Pb) and
Food Sci. Technol. Publicado em: 10/12/2018
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8. Mineralogy and Concentration of Potentially Toxic Elements in Soils of the São Francisco Sedimentary Basin
ABSTRACT Lithological and geomorphological variations determine formation of soils with different mineralogical constitutions and can influence the distribution of potentially toxic elements (PTE). The aim of this study was to determine the contents of PTE and mineralogical assemblages along soil profiles of different classes and parent materials and to inve
Rev. Bras. Ciênc. Solo. Publicado em: 24/05/2018
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9. Alguns macro elementos e traços em vários tecidos de variação de peixe Van de acordo com sexo e peso
RESUMO Peixes van são a única espécie de peixe vivendo em pH 9-10 no mundo. A área de pescaria Van é uma fonte importante de proteína para a população. As variações de niveis de metal nos tecidos de acordo com sexo e peso do peixe Van (Alburnus tarichi, Güldenstadt 1814) foram estudadas. Esse é o primeiro estudo conduzido com peixes Van. São imp
Arq. Bras. Med. Vet. Zootec.. Publicado em: 2018-01
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10. Cu-Sn Coatings Produced Using Environmentally Non-Aggressive Electrolyte Containing Sodium Tartrate
This work proposes the production of Cu-Sn alloy coatings with anticorrosive properties, using an environmentally non-aggressive bath. The coatings were electrodeposited on carbon steel substrate AISI 1020 using an electrolyte containing CuCl2 and SnCl2, and sodium tartrate as the complexant agent. The produced coatings were characterized by scanning electro
Mat. Res.. Publicado em: 27/11/2017
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11. Potency of ZnFe2O4 Nanoparticles as Corrosion Inhibitor for Stainless Steel; the Pigment Extract Study
The corrosion inhibition of nanoparticulates zinc ferrite (NZF) pigment was studied. The steel samples were immersed in the NZF pigment extract in 3.5 wt. % NaCl. Electrochemical tests such as electrochemical impedance spectroscopy (EIS) and polarization as well as surface analysis were employed to evaluate the effect of NZF on the steel corrosion. The conce
Mat. Res.. Publicado em: 17/08/2017
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12. Influence of Aluminum Addition in the Framework of MCM-41 Mesoporous Molecular Sieve Synthesized by Non-Hydrothermal Method in an Alkali-Free System
Purely siliceous MCM-41 and Al-containing MCM-41 (Al-MCM-41) mesoporous materials were synthesized by non-hydrothermal method in alkali-free ions medium at room temperature and short reaction times. Under these synthesis conditions, it was also investigated the influence of Al incorporation in the crystal structure of MCM-41. The solids were characterized by
Mat. Res.. Publicado em: 17/08/2017