Solid Solutions
Mostrando 1-12 de 276 artigos, teses e dissertações.
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1. Innovative gas chromatographic determination of formaldehyde by miniaturized extraction and on-fiber derivatization, via SPME and SPME Arrow
Formaldehyde (FA) is a carbonyl compound, ubiquitous in the environment and among the most widespread pollutants: it has exhibited toxic properties and is classified as a human carcinogen. FA is released from several sources, both temporary (e.g., combustion processes) and permanent (e.g., building products). This work proposes an innovative fully-automated
Química Nova. Publicado em: 2022
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2. Dispersive Solid-Phase Extraction Using 3-Mercaptopropyltrimethoxysilane Functionalized Magnetic MWCNT-Based Nanocomposite for Selective and Efficient Preconcentration of Pb2+ with FAAS Determination
A novel nanocomposite based on magnetic multiwalled carbon nanotubes coated with SiO2 and functionalized with 3-mercaptopropyltrimethoxysilane (3-MPTMS) was prepared for the efficient extraction and quantification of lead ions from water samples. The adsorption capacity of this adsorbent could reach 1.995 mg g-1 Pb2+ in an equilibrium time of 30 min. Under o
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Understanding Solvent/Bixin Interactions by Raman Spectroscopy
In this work, Raman spectroscopy and density functional theory (DFT) calculations have been used in order to understand the nature of the interaction between the carotenoid bixin and organic solvents with dielectric constant varying from ca. 2 (toluene) to ca. 47 (dimethyl sulfoxide). Raman shifts registered for the main carotenoid marker band, the C=C stret
J. Braz. Chem. Soc.. Publicado em: 2020-07
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4. A evolução histórica da drenagem urbana: da drenagem tradicional à sintonia com a natureza
RESUMO No Brasil, mais de 80% da população brasileira vive em cidades. Como consequência desse crescimento populacional, há impermeabilização do solo, ocupação das faixas marginais de proteção dos rios, desmatamentos, canalização de rios, quantidade crescente de resíduos sólidos que são jogados nesses corpos hídricos, dentre outras. Quando oc
Saúde debate. Publicado em: 13/01/2020
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5. A study on the compressive strength and microstructure characteristic of alkali-activated metakaolin cement
ABSTRACT The main purpose of this study was to investigate the compressive strength and microstructure characteristic of alkali-activated metakaolin cement (AAMC). In accordance with this purpose, besides the pure metakaolin activation five other mixtures were designed by substitution of different OPC ratios instead of metakaolin (MK) from 0 to 25 (5, 10, 15
Matéria (Rio J.). Publicado em: 25/11/2019
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6. Aplicação de solução semianalítica para modelagem de ensaios de sorção e difusão pura com lixiviado
RESUMO A implementação da Política Nacional de Resíduos Sólidos (Lei nº 12.305, de 2 de agosto de 2010) foi um marco para a disposição final e o tratamento de resíduos sólidos no país. A contaminação decorrente da negligência na disposição dos resíduos sólidos urbanos atinge sistemas naturais vitais para a existência humana. Torna-se, port
Eng. Sanit. Ambient.. Publicado em: 25/11/2019
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7. Activated carbon loaded with manganese and iron for glyphosate adsorption: Kinetics, isotherms and thermodynamic studies
Resumo Carvão ativado granular foi impregnado com 1% de ferro e 0,5% de manganês (m/m) para remoção de glifosato em soluções aquosas. O adsorvente foi caracterizado por microscopia eletrônica de varredura, espectroscopia de energia dispersiva, técnicas de adsorção de nitrogênio e análises de potencial zeta. Estudos em batelada foram realizados pa
Rev. Ambient. Água. Publicado em: 25/11/2019
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8. Kinetic Analysis of Lead Removal by Natural Hydroxyapatite from Aqueous Solution in High Concentration
The aim of this work was to study of the kinetic of Pb(II) sorption, in high lead concentration aqueous solution, by the natural hydroxyapatite (HA) and to verify whether there is a different behavior between natural and synthetic HA under different lead concentrations. Batch experiments were carried out using solutions with high lead concentration, with the
Mat. Res.. Publicado em: 30/09/2019
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9. Effects of Aging Temperature, Time, and Pre-Strain on Mechanical Properties of AA7075
Aluminum alloys of the 7xxx series (AA7075) are preferred in the aerospace and automotive industries due to their low densities, high strength, good corrosion resistance properties. Additionally, these alloys show the most effective aging properties among aluminum alloys. For this reason, it is very important to determine the most appropriate aging parameter
Mat. Res.. Publicado em: 12/09/2019
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10. DEVELOPMENT OF INEXPENSIVE CELLULOSE-BASED SORBENTS FOR CARBON DIOXIDE
ABSTRACT Aqueous amine solutions are benchmark solvents for CO2 capture and their operational drawbacks are well-known. In order to overcome these problems, the support of amines on solid materials appears as an option for CO2 capture. Cellulose is a versatile and low-cost material that can be used as a support. This study reports chemical modification of ce
Braz. J. Chem. Eng.. Publicado em: 15/07/2019
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11. Determination of Plant Growth Regulators in Chinese Herbal Medicine: A Comparison of Liquid (QuEChERS) and Solid (MSPD) Extraction Methods
This work aimed to compare the methods for the determination of twenty plant growth regulators (PGRs) from Chinese herbal medicines by applying liquid and solid extraction methods simultaneously. Quick, easy, cheap, effective, rugged and safe (QuEChERS) and matrix solid-phase dispersion (MSPD) were chosen as the liquid and solid extraction methods, respectiv
J. Braz. Chem. Soc.. Publicado em: 04/07/2019
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12. Dispersive Solid Phase Extraction Headspace Sampling in Gas Chromatography-Mass Spectrometric Analysis of Volatiles: Application to Separation of Polycyclic Aromatic Hydrocarbons
For the first time, dispersive solid phase extraction combined with headspace sampling was introduced and applied to separation and pre-concentration of polycyclic aromatic hydrocarbons (PAHs) as representative of volatile and semi-volatile compounds, from aqueous solutions and sediments using multiwall carbon nanotubes (MWCNTs). After adsorption, PAHs were
J. Braz. Chem. Soc.. Publicado em: 2019-04