Chemical Elements
Mostrando 1-12 de 548 artigos, teses e dissertações.
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1. Solventes eutéticos naturais profundos (NADES) no preparo de amostras de rocha fosfática e suplemento mineral para determinação elementar por técnicas de plasma
Natural deep eutectic solvents (NADES) based on xylitol, citric acid, and malic acid were synthesized and used in ultrasound-assisted extraction (UAE) and heating-bath extraction of phosphate rock and mineral supplement samples. Arsenic, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, P and Zn were determined by inductively coupled plasma mass spectrometry (ICP-MS) and i
Quím. Nova. Publicado em: 2021-06
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2. Synthesis, Characterization, and Application of Europium(III) Complexes as Luminescent Markers of Banknotes
In this work, three complexes were synthesized from the trivalent europium ion (EuIII), using the picrate anion (pic), and delta-valerolactam (DVL), epsilon-caprolactam (EPK), and oenantholactam (OEN). The synthesized complexes [Eu(pic)3·(DVL)3], [Eu(pic)3·(EPK)3], and [Eu(pic)3·(OEN)3] were studied as luminescent markers for application as security eleme
J. Braz. Chem. Soc.. Publicado em: 2021-05
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3. WILHELM OSTWALD PARA ALÉM DO ANTIATOMISMO
The Baltic German chemist Wilhelm Ostwald (1853-1932) had his scientific prestige eclipsed in the history of chemistry due to his rejection to atomic theory, which suggests the permanence of the whig interpretation on history of chemistry in the narratives about him. In this paper, we intend to present elements on Ostwald’s biography far from his role in t
Quím. Nova. Publicado em: 2021-02
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4. Yellow Mombin (Spondias mombin L.) Seeds from Agro-Industrial Waste as a Novel Adsorbent for Removal of Hexavalent Chromium from Aqueous Solutions
The objective of this study was to develop a low-cost and eco-friendly adsorbent from agro-industrial waste for the removal of hexavalent chromium in the aqueous medium. The adsorbent (BMC) produced from yellow mombin (Spondias mombin L.) seeds was characterized by the determination of the chemical composition, thermal analysis (thermogravimetric (TG) analys
J. Braz. Chem. Soc.. Publicado em: 2021-02
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5. Investigation of some properties of gluten-free tarhanas produced by red, green and yellow lentil whole flour
Abstract Gluten-free lentil tarhanas were obtained by replacing red, green and yellow lentil whole flour instead of wheat flour used in traditional tarhana formulation. Some physical, chemical, bioactive, microbiological, reological, morphological and sensory properties of these tarhanas were investigated comparatively. Amount of crude protein (%), crude ash
Food Sci. Technol. Publicado em: 2020-12
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6. Microstructural and mechanical characterisation of the Simon Bolivar's iron bridge structure, 19th century, Arequipa, Peru
Abstract The microstructure of the main structural elements (Phoenix columns, transversal beams and tie-rods) of the Simón Bolivar iron bridge, located in Arequipa (Peru), was investigated. The bridge was supposedly designed by Gustave Eiffel and opened to the public in 1882. The characterisation revealed that the columns, beams and tie-rods are made of pud
REM, Int. Eng. J.. Publicado em: 2020-12
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7. ENRIQUECIMENTO ELEMENTAR POR MEIO DE CULTIVO: PLANTAS E COGUMELOS
The foods enrichment with essential elements is an alternative to supply deficiencies of micronutrients and the fortification by rich cultivation is a promising strategy for the elemental enrichment of agricultural origin products, mainly in regions where there is high prevalence. On the other hand, in elemental enrichment procedures, possible antagonistic a
Quím. Nova. Publicado em: 2020-09
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8. A UNIFIED FORMULA FOR HYDROCARBONS WITH APPLICATIONS TO FUNCTIONAL GROUPS
Was supposed a numerical relationship between atoms of Hydrogen and Carbon in a hydrocarbon, assumption valid for all types of chains. In the proposed equation, variables such as number and types of carbon bonds are present, as well as the possible cycles. It was shown that the equation reduces to the known “general formulas” when applied to the type of
Quím. Nova. Publicado em: 20/07/2020
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9. Quality pattern evaluation of frozen soursop pulps: an assessment based on chemical composition and chemometric analysis
Abstract In the present study, the physicochemical properties and mineral composition of commercially-frozen soursop pulps from the southern region of the state of Bahia, Brazil, were evaluated. The physicochemical parameters such as soluble solids (°Brix), acidity and pH were determined according to reference methodologies. For mineral composition evaluati
Food Sci. Technol. Publicado em: 2020-06
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10. Chemical and structural composition of black pigmented supragingival biofilm of bovines with periodontitis
RESUMO: A periodontite bovina é uma infecção multifatorial associada primariamente à microbiota potencialmente patogênica presente no biofilme bucal. Biofilmes são estruturas organizadas, nas quais os constituintes convivem em simbiose, descritos em outras espécies como um fator predisponente à periodontite. O objetivo do presente estudo foi caracter
Pesq. Vet. Bras.. Publicado em: 10/01/2020
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11. Cation Vacancies in NiFe2O4 During Heat Treatments at High Temperatures: Structural, Morphological and Magnetic Characterization
Nickel ferrite (NiFe2O4) was synthesized by mixing stoichiometric amounts of α-Fe2O3 and NiO using mechanical milling and heat treatments at high temperatures. The physical characterization of the samples was carried out using X-ray diffraction, infrared and Raman spectroscopies, Mössbauer spectrometry, magnetization measurements, scanning electron microsc
Mat. Res.. Publicado em: 20/12/2019
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12. Quality pattern evaluation of frozen soursop pulps: an assessment based on chemical composition and chemometric analysis
Abstract In the present study, the physicochemical properties and mineral composition of commercially-frozen soursop pulps from the southern region of the state of Bahia, Brazil, were evaluated. The physicochemical parameters such as soluble solids (°Brix), acidity and pH were determined according to reference methodologies. For mineral composition evaluati
Food Sci. Technol. Publicado em: 13/12/2019