Hydrochloric Acid
Mostrando 1-12 de 220 artigos, teses e dissertações.
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1. Simple and fast process using hydrochloric acid for producing synthetic zinc-rich stevensite
Abstract In the last decades, clays have been used in sectors such as health and cosmetics. This requires products that are increasingly pure and present homogeneous properties, hardly found in natural clays. The use of synthetic clays can be a solution. For this, it is necessary to explore techniques for their production. The main focus of this study was to
Cerâmica. Publicado em: 2022
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2. Selective formation of neodymium phosphate from iron-neodymium magnet waste
Abstract Neodymium-iron-boron alloy, Nd2Fe14B, is used as a material for magnets. Neodymium is one of the valuable and expensive rare earth elements and is often recovered to reduce costs and environmental impact. Recently, a method for recovering neodymium as neodymium phosphate from mixed solutions was reported. This method was very useful because the main
Cerâmica. Publicado em: 2022
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3. Aqueous Extract of Cumaru (Dipteryx odorata) Seeds as Corrosion Inhibitor for Mild Steel in Hydrochloric Acid Solution
The corrosion inhibition of mild steel by aqueous extract of cumaru (Dipteryx odorata) seeds and its high molecular weight fraction (HMWF) was investigated in 1 mol L-1 HCl solution. The study was carried out through gravimetric essays, open circuit potential measurements, anodic and cathodic polarization curves and electrochemical impedance analyses, as wel
J. Braz. Chem. Soc.. Publicado em: 2021-02
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4. Improving seed germination and seedling growth of guava under heat and osmotic stresses by chemical and hormonal seed treatments
ABSTRACT This study, consisting of two independent experiments, was conducted to optimize presowing guava seed treatments and evaluate the optimized treatments in improving germination and seedling growth of guava under heat and osmotic stresses. In the first experiment, seeds of guava cultivar White Flesh Local I were soaked in water, gibberellic acid (GA3)
Bragantia. Publicado em: 2020-12
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5. Unexpected Rearrangement and Aromatization on Dehydration Reaction of the Bioactive Diterpenequinone 7α-Hydroxyroyleanone
7a-Hydroxyroyleanone is a bioactive diterpene isolated from leaves of Tetradenia riparia, active against tuberculosis and T. cruzi. In order to use this compound as starting material for the synthesis of compounds with enhanced bioactivity we aimed the dehydration of the 7-alpha-hydroxyl group of royleanone. The reaction performed in acetic acid and hydrochl
J. Braz. Chem. Soc.. Publicado em: 2020-03
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6. Use of Arduino in the Development of a New and Fast Automated Online Preconcentration System Based on Double-Knotted Reactor for the Mn Determination in Tea Samples by Flame Atomic Absorption Spectrometry (F AAS)
In the present paper, an automated online preconcentration system based on the use of two knotted reactors (KR) was developed for Mn determination in tea samples by flame atomic absorption spectrometry (F AAS). The system automation was performed by using four solenoid valves to switch sample streams and reagents. Valves were driven electronically by an inte
J. Braz. Chem. Soc.. Publicado em: 2020-01
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7. Long-term behavior of mortars produced with sulfide-bearing aggregates
ABSTRACT The variety of sulfides (inorganic compounds formed by combining sulfur with a metal element) presented in earth crust is not small, which makes it difficult to avoid the use of sulfide-bearing aggregates in the concrete, especially in places where another source of material is non-existent or economically impracticable, as is the case of dams. With
Matéria (Rio J.). Publicado em: 25/11/2019
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8. Obtenção de ferritas de cálcio dopadas com cromo visando aplicação em esmaltes transparentes brilhante e mate
RESUMO Este trabalho tem como objetivo obter óxidos com estrutura tipo espinélio de composição CaFe1,8Cr0,2O4 pelo método gelatina, visando aplicação em esmaltes transparentes brilhantes e mate. Os pós precursores, resultantes do processo de síntese, foram calcinados a 600 °C e a 800 °C para a obtenção da fase espinélio. Os pós foram caracteri
Matéria (Rio J.). Publicado em: 25/11/2019
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9. Biomonitoring of Heavy Metals (Fe, Zn, Cu, Mn, Cd and Cr) in Oysters: Crassostrea rhizophorae of Mangrove Areas of Alagoas (Brazil)
Abstract Mangroves are tropical and subtropical flooded forests that generally develop in estuarine areas over unstable sediments protected from the action of waves in the intertidal zone with an environment characterized by a great diversity of fauna and flora. Thus, the present study aimed to evaluate the levels of heavy metals that are absorbed by mangrov
Braz. arch. biol. technol.. Publicado em: 24/10/2019
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10. In Situ Effect of Intra-Oral Application of Pastes Containing CPP-ACP or CPP-ACPF Against Initial Enamel Erosion
Abstract Objective: To evaluate in situ the effect of toothpastes containing casein phosphopeptide - amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide-amorphous calcium phosphate associated to fluoride (CPP-ACPF) on initial erosion prevention. Material and Methods: Bovine enamel blocks (n = 192) were randomly assigned into 4 phases according
Pesqui. Bras. Odontopediatria Clín. Integr.. Publicado em: 10/10/2019
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11. Contents of total phenolics and flavonoids in and antioxidant activity of Ilex paraguariensis leaves
Resumo: O objetivo deste trabalho foi avaliar diferentes solventes e tempos de extração de polifenóis com ultrassom, para quantificar os compostos fenólicos e flavonoides totais e a capacidade antioxidante em folhas de erva-mate (Ilex paraguariensis). O experimento foi realizado em delineamento inteiramente casualizado, em arranjo fatorial 8x3 (solvente
Pesq. agropec. bras.. Publicado em: 07/10/2019
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12. Estudo da eficiência do Orbignya oleifera como inibidor verde de corrosão para aço com baixo teor de carbono comparado com inibidor comercial em solução HCl 1M
RESUMO O trabalho visa um estudo comparativo entre a eficiência do óleo de coco babaçu (Orbignya oleifera) utilizado como inibidor verde de corrosão e um inibidor comercial testados em aço ABNT 1020 em meio contendo ácido clorídrico. A avaliação foi realizada utilizando técnicas eletroquímicas de polarização linear aliado ao Método de Extrapola
Matéria (Rio J.). Publicado em: 16/09/2019