Chemical Speciation
Mostrando 1-12 de 67 artigos, teses e dissertações.
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1. QUANTITATIVE SPECIATION OF THE LIQUID PHASE BY FTIR SPECTROSCOPY IN THE SYSTEM AMP-PZ-CO2-H2O
This work reports a multivariate calibration partial least square regression (PLS) model to quantify the liquid-phase concentrations of 2-amino-2-methyl-1-propanol (AMP), piperazine (PZ), bicarbonate, PZ monocarbamate, and PZ dicarbamate during the absorption/desorption process by Fourier Transform Mid-Infrared spectroscopy (mid-FTIR). The model could predic
Química Nova. Publicado em: 2022
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2. AVALIAÇÃO DE NANOTUBOS DE CARBONO FUNCIONALIZADOS VISANDO O DESENVOLVIMENTO DE MÉTODOS DE PRÉ-CONCENTRAÇÃO DE ÍONS METÁLICOS E DETERMINAÇÃO POR TÉCNICAS ESPECTROMÉTRICAS E ELETROANALÍTICAS
This review focuses on the use of functionalized carbon nanotubes (CNTs) on the development of preconcentration methods with substantial contributions on selectivity and sensitivity for metal ions determination. CNTs have been usually employed in the development of preconcentration/speciation coupled to spectroanalytical techniques for ions determination at
Quím. Nova. Publicado em: 2020-09
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3. NANOESPECTROSCOPIA DE ABSORÇÃO DE RADIAÇÃO SÍNCROTRON NO INFRAVERMELHO PARA NANOESPECIAÇÃO DE PRODUTOS DE CORROSÃO METÁLICA
The understanding of chemical and physical behavior of materials, especially metals and their alloys, is of utmost importance for industrial and technological applications, development of new materials and preservation of cultural heritage. The use of complementary analytical techniques has allowed a better understanding of corrosion mechanisms, and results
Quím. Nova. Publicado em: 05/12/2019
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4. Elemental Concentration and Sulfur Chemical Speciation in the Amazonian Plant Andira surinamensis Using Synchrotron Radiation Techniques (SR-XRF, XANES), RBS and WD-XRF
The inorganic composition of the bark and leaf of a plant from the Amazon rainforest, Andira surinamensis, was determined using two non-destructive, multi-element techniques: X-ray fluorescence (XRF) and Rutherford backscattering spectrometry (RBS). XRF measurements were made using both a conventional X-ray source and synchrotron radiation. It was observed t
J. Braz. Chem. Soc.. Publicado em: 16/09/2019
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5. MODELOS FOTOQUÍMICOS SIMPLES COMO FERRAMENTA PARA O GERENCIAMENTO DA QUALIDADE DO AR
Atmospheric processes in an urban scenario are very complex and depend on meteorological parameters, emission, transport and deposition processes and the chemical mechanism. Simple air quality models can be used to understand the main aspects of ozone formation and provide information to adopt pollution control strategies. In this work the detailed simulatio
Quím. Nova. Publicado em: 02/05/2019
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6. Chemical Species and Aluminum Concentration in the Solution of Acid Soils Cultivated with Soybean and Corn under Liming
ABSTRACT Chemical speciation of the soil solution is an important tool to identify Al species related to phytotoxicity. In some Brazilian acid soils, the Al extractable by the KCl 1.0 mol L -1 solution (Al-KCl) exceeds 10 cmol c kg -1 and even then, in some situations, it does not cause toxicity to the plants. This study aimed to evaluate the relationship be
Rev. Bras. Ciênc. Solo. Publicado em: 18/10/2018
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7. QUÍMICA ANALÍTICA NO BRASIL: ATUALIDADES, TENDÊNCIAS E DESAFIOS
This work describes the development of Analytical Chemistry in Brazil from the Brazilian Chemical Society (SBQ) foundation to the present days. Important historical facts were highlighted and data on the human resources formation, financial investments and scientific production were used to evaluate and contextualize the progress achieved. The evolution of t
Quím. Nova. Publicado em: 2017-07
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8. The current status of the Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) species complex
Lutzomyia longipalpis s.l. is a complex of sibling species and is the principal vector of American visceral leishmaniasis. The present review summarises the diversity of efforts that have been undertaken to elucidate the number of unnamed species in this species complex and the phylogenetic relationships among them. A wide variety of evidence, including chem
Mem. Inst. Oswaldo Cruz. Publicado em: 2017-03
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9. Chemical Speciation of Iron in Different Varieties of Beans (Phaseolus vulgaris L.): Cooking Effects
Beans are considered a source of iron (Fe), and hence have considerable contribution in cases of Fe deficiency. Beans also contain certain anti-nutritional constituents, which are imperative to the cooking of beans. The nutritional value of beans depends on the bioavailability, which can be affected by cooking. Studies about heating effects in distribution o
J. Braz. Chem. Soc.. Publicado em: 2015-10
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10. Developing Fast and Facile Method for Speciation Analysis of Vanadium (V/IV) Ions with Calmagite Immobilization on Triacetyl Cellulose Membrane in Water Samples
An inexpensive and fast vanadium [(IV), (V)] speciation method was performed by using optical chemical sensor that incorporates lipophilized calmagite (Cal) with cetyl pyridinium chloride (CPC) as a suitable ligand on triacetylcellulose membrane in aqueous solutions prior to UV-Vis spectrometric determination. Absorbance decrease of the optode in pH 6 at 490
J. Braz. Chem. Soc.. Publicado em: 2015-03
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11. ARSÊNIO E ARROZ: TOXICIDADE, METABOLISMO E SEGURANÇA ALIMENTAR
Arsenic is considered a semimetal, and its wide distribution in the Earth's crust in different chemical forms, including organic and inorganic species, has a great deal of influence on the mechanisms of toxicity. Exposure to arsenic can be either through occupational practice (use of pesticides) or by the consumption of water and food containing the element.
Quím. Nova. Publicado em: 2015-01
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12. Especiação química de arsênio inorgânico no estuário da Laguna dos Patos (RS, Brasil)
This study optimized and validated a method to perform chemical speciation of inorganic arsenic in water samples collected under the Monitoring Program of the Port of Rio Grande-RS in July and October 2010 from the Laguna dos Patos Estuary (RS, Brazil). The flow injection hydride generation atomic absorption spectrometry technique was employed, allowing quan
Química Nova. Publicado em: 2012