Weak Solution
Mostrando 1-12 de 167 artigos, teses e dissertações.
-
1. VIBRATION CHARACTERISTICS, CHEMICAL BONDS AND WEAK INTERACTIONS OF 4- AND 5-HYDROXYSALICYLIC ACID INVESTIGATED BY TERAHERTZ SPECTROSCOPY AND DENSITY FUNCTIONAL THEORY
The terahertz (THz) absorption spectra of 4- and 5-hydroxysalicylic acid were measured by terahertz time-domain spectroscopy (THz-TDS) in the range of 0.4-2.8 THz. The unit cells of both were calculated by density functional theory (DFT), and the theoretical simulation and experimental data were basically in agreement. To further interpret the origin of the
Química Nova. Publicado em: 2022
-
2. NO Photorelease from a Ruthenium Complex Assisted by Formation of a Supramolecular Dimer
This work presents the NO release from compound [Ru(biq)2(H2O)(NO)](PF6)3 (biq = 2,2’-biquinoline) with visible light irradiation (λirrad = 660 nm), assisted by the low-absorbing photosensitizer [Ru(biq)2Cl2]. The structure of both compounds were characterized by means of ESI-MS (electrospray ionization mass spectrometry). The NO+ stretching, ν(NO) = 199
J. Braz. Chem. Soc.. Publicado em: 2020-11
-
3. Synthesis, Characterization, Spectroelectrochemical, Photophysical and HSA-Binding Properties of Novel and Versatile meso-Tetra(4-pyridylvinylphenyl)porphyrins Coordinated to Ruthenium(II)-Polypyridyl Derivatives
The free-base meso-tetra(4-pyridylvinylphenyl)porphyrin (1a) and its zinc(II) complex were synthesized and then functionalized with [Ru(bpy)2Cl]+ units (2a and 2b) via conventional methods and evaluated in terms of photophysical, electrochemical and biological aspects. All porphyrins present moderate singlet oxygen production and fluorescence quantum yield,
J. Braz. Chem. Soc.. Publicado em: 2020-11
-
4. Imiquimod/β-Cyclodextrin Inclusion Complex: Experimental and Theoretical Studies
Imiquimod (IMQ), an immune response modifier, is used for topical treatment of basal cell carcinoma and actinic keratosis. The very poor aqueous solubility of imiquimod gives rise to difficulties in designing aqueous formulations with this drug. One approach that is widely used to enhance drug solubility is complexation with cyclodextrins. The formation of t
J. Braz. Chem. Soc.. Publicado em: 2020-08
-
5. Separation of gadolinium and europium from chloride media by the solvent extraction technique
Abstract Obtaining rare earth elements (REE) is a complicated task, due mainly to the difficulty of separating and purifying them. Solvent extraction is the most widely used technique for separating REE, and the most common extractants used are organophosphorus acids. The low selectivity of this technique leads to the need for a high number of extraction cel
REM, Int. Eng. J.. Publicado em: 2020-03
-
6. Condições de Otimalidade para Problemas Multiobjetivos Irregulares
RESUMO Neste artigo, consideramos problemas de Otimização multiobjetivo com restrições de igualdade dadas na forma F ( x ) = 0, sendo F : U ⊆ R n ⟶ R m e U um aberto não vazio. Consideramos o caso em que a restrição do problema é irregular, ou seja, quando a condição de qualificação de independência linear (LICQ) não é satisfei
TEMA (São Carlos). Publicado em: 13/12/2019
-
7. Applicability of papain solutions in immunohematology
RESUMO Objetivo: Comparar a atividade enzimática de diferentes apresentações de solução de papaína para validação de preparados in-house. Métodos: Foram preparadas duas soluções de papaína, e a terceira apresentação tratou-se de uma solução comercial. Os testes comparativos das reações enzimáticas foram realizados com amostras de hemáci
Einstein (São Paulo). Publicado em: 02/05/2019
-
8. MEASURING THE CONDUCTIVITY OF VERY DILUTE ELECTROLYTE SOLUTIONS, DROP BY DROP
Undergraduate experiments on ionic conductivity are common practice in general chemistry and advanced physical chemistry laboratories. Often, the conductivities are measured for solutions prepared for various salts, in a range of concentrations, and the relationship between solution conductivity and concentration is interpreted in terms of the Kohlrausch law
Quím. Nova. Publicado em: 2018-07
-
9. PROCESSING OF SPENT ZINC-MnO2 DRY CELLS IN VARIOUS ACIDIC MEDIA
This paper describes a route for recovering manganese and zinc from spent zinc-MnO2 dry cells via acid leaching. Sulfuric, hydrofluoric and formic acids were used as leachants. Hydrogen peroxide was added as reductant, except for formic acid since it is itself a reductant. Experiments were run at 25-40 ºC for 1-3 h. Under the best optimal conditions, over 9
Quím. Nova. Publicado em: 2018-02
-
10. Carbon nanotube buckypaper reinforced polymer composites: a review
Abstract This review provides valuable information about the general characteristics, processing conditions and physical properties of carbon nanotube buckypaper (BP) and its polymer composites. Vacuum filtration is the most common technique used for manufacturing BP, since the carbon nanotubes are dispersed in aqueous solution with the aid of surfactant. Pr
Polímeros. Publicado em: 21/09/2017
-
11. Application of a Greedy Algorithm to Military Aircraft Fleet Retirements
ABSTRACT This article presents a retirement analysis model for aircraft fleets. By employing a greedy algorithm, the presented solution is capable of identifying individually weak assets in a fleet of aircraft with inhomogeneous historical utilization. The model forecasts future retirement scenarios employing user-defined decision periods, informed by a cost
J. Aerosp. Technol. Manag.. Publicado em: 20/07/2017
-
12. Acidity and Characterization of 12-Tungstophosphoric Acid Supported on Silica-Alumina
This work deals with preparation and characterization of H3PW12O40 (H3PW) supported on silica-alumina. Impregnation of H3PW (15, 20, 30 and 40 wt.%) on commercial silica-alumina support in acidic aqueous solution is effective for preparing this catalyst keeping its Keggin structure, according to different methods of characterization. The catalysts were teste
J. Braz. Chem. Soc.. Publicado em: 2017-02