Absorptivity
Mostrando 1-12 de 47 artigos, teses e dissertações.
-
1. TD-DFT Analysis of the Dissymmetry Factor in Camphor
The fact that the dissymmetry lgeb (g-factor) of camphor is large has been known for decades, and the interpretation of the observed data has also been known for a long time. However, due to the ability of quantum chemical methods to describe chiroptical phenomena more appropriately, additional approaches based on these methods have been successful employed.
J. Braz. Chem. Soc.. Publicado em: 2020-03
-
2. NEW APPLICATIONS FOR AMOXICILLIN DETERMINATION IN PURE FORM AND PHARMACEUTICALS BASED ON IODATE-IODIDE MIXTURE: TITRIMETRY AND SPECTROSCOPY STUDIES
Three simple methods are described for the determination of amoxicillin (AMX) in bulk drug and dosage forms using iodate-iodide mixture reagent. These methods employed the well-known analytical reaction between iodate-iodide mixture in the presence of acid solution. The iodide oxidized by iodate to iodine in an amount equivalent to the -COOH group present in
Quím. Nova. Publicado em: 2020-01
-
3. Chitosan Imparts Better Biological Properties for Poly(ε-caprolactone) Electrospun Membranes than Dexamethasone
Poly(ε-caprolactone), an aliphatic polyester with biodegradability and cytocompatibility, has been used to create scaffolds for tissue engineering purposes. However, the hydrophobicity and low water absorptivity of poly(ε-caprolactone) reduce cell anchorage on their membranes. Here, poly(ε-caprolactone)-based scaffolds were prepared by electrospinning of
J. Braz. Chem. Soc.. Publicado em: 12/08/2019
-
4. Characterization of new selective coatings, made of granite and chrome, for solar collectors
ABSTRACT The depletion of fossil fuel reserves and climate change caused by atmospheric pollution has led the human being to seek alternatives that are less damaging to the environment. The concern and the awareness of the population open space for the study of renewable energies to be deepened, among them the best use of solar energy. The use of alternative
Matéria (Rio J.). Publicado em: 10/06/2019
-
5. Determination of cefotaxime, cefoperazone, ceftazidime and cefadroxil using surface plasmon resonance band of silver nanoparticles
The aim of this work is to evaluate simple, sensitive, effective and validated procedures for the determination of cefotaxime, cefoperazone, ceftazidime and cefadroxil. In this study, the methods based on the ability of the cited drugs to reduce Ag+ ions to silver nanoparticles (Ag-NPs) in the presence of Polyvinyl Pyrrolidone (PVP) as a stabilizing agent pr
Braz. J. Pharm. Sci.. Publicado em: 29/11/2018
-
6. New 9-Aminoacridine Derivative: Synthesis, Study and Potential Application as pH Indicator in Organic Solvents
In this work, we describe the synthesis of a novel 9-aminoacridine derivative that presents surprisingly different colors when exposed to neutral, acidic or basic mediums with potential application as pH indicator in organic solvents. Furthermore, pKa and molar absorptivity values were determined and theoretical studies supported by density functional theory
J. Braz. Chem. Soc.. Publicado em: 2017-12
-
7. Assembly and Testing of a Thermal Control Component Developed in Brazil
ABSTRACT: The optical solar reflector is basically a mirror of second surface with low absorptivity/emissivity ratio and negligible degradation in the space environment, which makes it an excellent coating for thermal control of satellites. It works as a radiator and is used in particular parts of the external surfaces of the satellites in order to reject th
J. Aerosp. Technol. Manag.. Publicado em: 2017-06
-
8. Synthesis, Characterization and Dielectric Properties of New 5-(4-Hydroxyphenyl)- 10,15,20-tri-4-[2-(3-pentadecylphenoxy)ethoxy]phenyl porphyrin and Their Ni, Co and Cu Complexes
New asymmetric cardanol-based porphyrins, free-base and coordinated with Ni, Co and Cu, were synthesized and completely characterized as A3B type. Such porphyrins were obtained aiming improved solubility in polar solvents due insertion of an -OH phenolic group. Their thermal and dielectric properties were also evaluated. Changes in the synthetic route reduce
J. Braz. Chem. Soc.. Publicado em: 2017-06
-
9. Macauba ( Acrocomia aculeata ) pulp oil quality is negatively affected by drying fruits at 60 ºC
ABSTRACT This study aimed to determine if the quality of macauba pulp oil is affected by drying the whole fruits at 60 ºC. Mature fruits were collected at every five days on the ground under 10 palm trees. A mixed batch of 3 kg of whole fruits, with three replications each, was dried in an oven with air circulation for 0, 12, 24, 36 and 48 h at 60 ºC. Afte
Braz. arch. biol. technol.. Publicado em: 02/05/2017
-
10. Development and Validation of a New Spectrophotometric Method for the Determination of Cephalexin Monohydrate in Pure Form and Pharmaceutical Formulations
A simple, fast, sensitive and accurate spectrophotometric method has been developed for the quantitative determination of cephalexin monohydrate in dosage form and in commercial formulations. The method involves the addition of CeIV to cephalexin in acidic medium, followed by the determination of residual CeIV by reacting with a fixed amount of methyl orange
J. Braz. Chem. Soc.. Publicado em: 2016-05
-
11. Ação antioxidante de extratos de especiarias e suas misturas binárias e ternárias sobre a estabilidade oxidativa de óleo de soja / Antioxidant activity of spices extracts and their binary and ternary mixtures on soybean oil oxidative stability
The lipid oxidation produces undesirable compounds that alter the organoleptic characteristics of food lipids and reduce the nutritional quality. In the food, cosmetics and pharmaceutical industries, synthetic antioxidants are added to retard or prevent the lipid deterioration. Due to the possible toxicity of synthetic antioxidants and the call for active na
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/10/2012
-
12. Studies on the development of spectrophotometric method for the determination of haloperidol in pharmaceutical preparations
A spectrophotometric method based on the formation of ion-pair complex between haloperidol and eriochrome black T (EBT) at pH 1.85 has been described. The formed complex was extracted quantitatively into chloroform and measured at 510 nm. Infra red (IR) studies were performed to confirm the formation of ion-pair complex. Beer's law was obeyed in the concentr
Química Nova. Publicado em: 2012