Acetates
Mostrando 1-12 de 59 artigos, teses e dissertações.
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1. Theoretical Study of the Reactivity of Phenyl Radicals Toward Enol Acetates
Arylation reactions are an important class of reactions and allow the synthesis of natural and synthetic products. Despite the efficient, but high cost and toxic methodologies involving transition metals, radical arylations have gained importance after the advent of photoredox catalysis. Arylation of enol acetates is an important tool for obtaining aryl keto
J. Braz. Chem. Soc.. Publicado em: 2021-02
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2. Mitral Valve Replacement with Regent Aortic Valve in Severe Mitral Stenosis
Arylation reactions are an important class of reactions and allow the synthesis of natural and synthetic products. Despite the efficient, but high cost and toxic methodologies involving transition metals, radical arylations have gained importance after the advent of photoredox catalysis. Arylation of enol acetates is an important tool for obtaining aryl keto
Int. J. Cardiovasc. Sci.. Publicado em: 2021-02
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3. APROVEITAMENTO DE PRECURSORES LIGNOCELULÓSICOS PARA PRODUÇÃO DE ACETATO DE CELULOSE
The feasibility of obtaining cellulose acetate from lignocellulosic precursors is of great interest from the environmental, economic and technological points of view. Herein, sugarcane bagasse and vegetable sponge (Luffa cylindrica ) were used as precursors to produce cellulose using the organosolv extraction procedure. From the extracted celluloses, the pro
Quím. Nova. Publicado em: 2020-03
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4. Effect of the degree of acetylation, plasticizer concentration and relative humidity on cassava starch films properties
Abstract The objective of this study was to develop films with reduced hygroscopicity and improved mechanical properties from acetylated cassava starch. For that, an acetylation procedure using acetic anhydride as the esterification reagent was performed, resulting in starch acetates with degrees of substitution (DS) of 0.6 (S0.6) and 1.1 (S1.1). Twelve fil
Food Sci. Technol. Publicado em: 07/01/2019
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5. Effect of the degree of acetylation, plasticizer concentration and relative humidity on cassava starch films properties
Abstract The objective of this study was to develop films with reduced hygroscopicity and improved mechanical properties from acetylated cassava starch. For that, an acetylation procedure using acetic anhydride as the esterification reagent was performed, resulting in starch acetates with degrees of substitution (DS) of 0.6 (S0.6) and 1.1 (S1.1). Twelve fil
Food Sci. Technol. Publicado em: 20/12/2018
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6. Synthesis and characterization of lithiated nanostructures
ABSTRACT Regardless of the simple accumulation of ions in the crystal insertion sites, nanomaterials offer a new storage mechanism of lithium ions (Li+), these storage mechanisms are formed in the interfaces and inside of the nanopores. Such kinds of storage mechanisms have no effect on the structure of the electrode material. Consequently, the charge-discha
Matéria (Rio J.). Publicado em: 19/07/2018
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7. Two mechanisms of oral malodor inhibition by zinc ions
Abstract Objectives The aim of this study was to reveal the mechanisms by which zinc ions inhibit oral malodor. Material and Methods The direct binding of zinc ions to gaseous hydrogen sulfide (H2S) was assessed in comparison with other metal ions. Nine metal chlorides and six metal acetates were examined. To understand the strength of H2S volatilization i
J. Appl. Oral Sci.. Publicado em: 18/01/2018
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8. Mg-Containing Hydroxyapatite Coatings Produced by Plasma Electrolytic Oxidation of Titanium
Plasma Electrolytic Oxidation (PEO) is promising for the processing of biomaterials because it enables the production of surfaces with adjustable composition and structure. In this work, aimed at the improvement of the bioactivity of titanium, PEO has been used to grow calcium phosphide coatings on titanium substrates. The effects of the addition of magnesiu
Mat. Res.. Publicado em: 30/03/2017
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9. Introdução à físico-química orgânica utilizando um colorímetro artesanal - uma prática interdisciplinar
Herein, we propose an interdisciplinary experiment for undergraduate course that involves concepts of organic and physical chemistry. Firstly, we propose the synthesis of three nitrophenyl acetates, varying the substituent position. Afterwards, we describe the construction of a homemade colorimeter using inexpensive materials and LED as both emission and det
Quím. Nova. Publicado em: 2017-02
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10. Pechini Synthesis of Nanostructured Li1.05M0.02Mn1.98O4 (M = Al3+ or Ga3+)
Doped Li1.05M0.02Mn1.98O4 (M = Ga3+ or Al3+) were prepared by Pechini synthesis using lithium and manganese acetates, citric acid, ethylene glycol, and the respective oxide or acetate of the doping ions in molar ratios of 2.00 (Mn1.98 + M0.02) to 1.05 Li. The TGA/DTA of the precursor gels showed weight loss/energy relative to crystallization below 450 ºC. F
Mat. Res.. Publicado em: 17/11/2015
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11. Caracterização de membranas assimétricas de acetato de celulose produzidas a partir do aproveitamento do resíduo da palha de milho para uso em ultrafiltração
Cellulose acetates (CA) with different degrees of acetylation were synthesized from cellulose extracted from corn stover. Membranes were prepared for the ultrafiltration process with pure polymers and blend form of CA utilizing a dioxane/acetone system. The membranes were characterized according to their transport properties. The blend form materials present
Quím. Nova. Publicado em: 2014-06
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12. Síntese, liofilização e caracterização de acetato de 57Fe(III)
Iron(III) acetate was synthesized by the reflux method using iron enriched in the 57Fe isotope and the compound processed by freeze-drying. The as-synthesized and freeze-dried acetates were characterized regarding their structural, thermal, vibrational and hyperfine properties. Similar diffractometric and spectroscopic results were found for both materials a
Quím. Nova. Publicado em: 2014