Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Materials (Basel) ; 15(24)2022 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-36556656

RESUMEN

P-type Sb2Te3 films with different thicknesses were deposited on polyimide substrates via heat treatment-assisted DC magnetron sputtering. The correlations between the thickness variance and the structure, dislocation density, surface morphology, thermoelectric properties and output power are investigated. As a result, it is clear that the film thickness and the heat treatment process during growth are related to the diffusion of deposited atoms on the substrate surface, leading to imperfection defects inside the films. The imperfections inside the films are affected by their properties. This work also presents the thermoelectric efficiency of a planar single leg of the deposited films with various thicknesses. The maximum power factor is 2.73 mW/mK2 obtained with a film thickness of 9.0 µm and an applied temperature of 100 °C. Planar Sb2Te3 produced a maximum output power of 0.032 µW for a temperature difference of 58 K.

2.
Front Nutr ; 8: 772220, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34938761

RESUMEN

The objective of this study was to investigate the possibility of using jellyfish (Lobonema smithii) for the production of nutritionally improved crackers. In this study, ground jellyfish were incorporated into different levels (20, 30, and 40%) to replace wheat flour in cracker formula. Physicochemical characteristics (linear expansion, hardness, and color) and sensory quality of the developed crackers were examined and compared with control crackers. The crackers with jellyfish were found significantly darker, with more brittleness, and less consumer accepted than the control samples (p < 0.05). Moisture content, a w, and thiobarbituric acid reactive substances (TBARS)-values of jellyfish crackers increased while the hardness of the jellyfish crackers decreased with increasing the storage time for both crackers stored at 35 and 45°C. The substitution of wheat flour with jellyfish led to high protein content in the crackers. The cracker with 30% of jellyfish gained characteristics of cracker, liking scores, as well as the subjective quality of the final product and had good physical and chemical conditions, being able to be consumed for 12 weeks stored at 35°C.

3.
Sensors (Basel) ; 21(7)2021 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-33916817

RESUMEN

We theoretically explore the potential of Si3N4 on SiO2 waveguide platform toward a wideband spectroscopic detection around the optical wavelength of 2 µm. The design of Si3N4 on SiO2 waveguide architectures consisting of a Si3N4 slot waveguide for a wideband on-chip spectroscopic sensing around 2 µm, and a Si3N4 multi-mode interferometer (MMI)-based coupler for light coupling from classical strip waveguide into the identified Si3N4 slot waveguides over a wide spectral range are investigated. We found that a Si3N4 on SiO2 slot waveguide structure can be designed for using as optical interaction part over a spectral range of interest, and the MMI structure can be used to enable broadband optical coupling from a strip to the slot waveguide for wideband multi-gas on-chip spectroscopic sensing. Reasons for the operating spectral range of the system are discussed.

4.
Food Chem ; 171: 123-7, 2015 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-25308651

RESUMEN

Anthocyanin, which is soluble in water and released into sugar steam during extraction, was investigated in this study. The anthocyanin content in refined sugar, plantation white sugar, soft brown sugar and raw sugar was determined using electron spin resonance (ESR) spectroscopy, which was operated at room temperature, and compared with spectra from standard anthocyanin. The ESR spectra of red and violet anthocyanins was predominantly g ≈ 2.0055, which corresponded to an unpaired electron located in the pyrylium ring. Signals for Fe(III) and Mn(II), which naturally occur in plants, were found in raw sugar, soft brown sugar and standard anthocyanin but were absent from refined sugar and plantation white sugar due to the refining process. In addition, the ESR results were correlated with the apparent colour of the sugar, which was determined using the method of the International Commission for Uniform Methods of Sugar Analysis and inductively coupled plasma optical emission spectroscopy.


Asunto(s)
Antocianinas/química , Carbohidratos/química , Espectroscopía de Resonancia por Spin del Electrón , Análisis de los Alimentos/métodos , Color , Compuestos Férricos/química , Hierro/química , Manganeso/química , Saccharum/química , Agua
5.
AAPS PharmSciTech ; 12(1): 132-40, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21181509

RESUMEN

The objectives of this study were to prepare push-pull osmotic tablets (PPOT) of felodipine using an interpolymer complex of chitosan (CS) and poly(acrylic acid) (PAA) as an osmopolymer, and to study the mechanisms of drug release from these tablets. The interpolymer complexes were prepared with different weight ratios of CS to PAA. Preparation of PPOT involved the fabrication of bilayered tablets with the drug layer, containing felodipine, polyethylene oxide, and the polymeric expansion layer, containing the CS-PAA complex. The effects of polymer ratios, type of plasticizers, and compression forces on release characteristics were investigated. It was found that drug release from PPOT exhibited zero-order kinetics and could be prolonged up to 12 or 24 h depending on the plasticizer used. PPOT using dibutyl sebacate showed a longer lag time and slower drug release than that using polyethylene glycol 400. In the case of polyethylene glycol 400, an increase in the CS proportion resulted in an increase in the drug release rate. The compression force had no effect on drug release from PPOT. Drug release was controlled by two consecutive mechanisms: an osmotic pump effect resulting in the extrusion of the drug layer from the tablet and subsequent erosion and dissolution of the extruded drug layer in the dissolution medium. The mathematical model (zero-order) related to extrusion and erosion rates for describing the mechanism of drug release showed a good correlation between predicted and observed values.


Asunto(s)
Resinas Acrílicas/química , Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/farmacocinética , Quitosano/química , Sistemas de Liberación de Medicamentos , Excipientes/química , Felodipino/química , Felodipino/farmacocinética , Administración Oral , Preparaciones de Acción Retardada , Composición de Medicamentos , Humanos , Ósmosis , Plastificantes , Polietilenglicoles , Polímeros , Solubilidad , Comprimidos
6.
Pharm Dev Technol ; 8(2): 135-42, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12760564

RESUMEN

Salbutamol elementary osmotic pump (EOP) tablets were developed, and fundamental variables affecting their release characteristics were evaluated. The effects of film thickness and compression force on drug release from the tablets containing fixed amount of sodium chloride used as osmogent were evaluated. The core tablets were directly compressed at four compression forces and coated with 3% wt/vol cellulose acetate in acetone to levels of 2%, 3%, and 4% wt/wt. Coated tablets were drilled with CO2 laser beam to form drug delivery orifice of approximately 400 microm in diameter. The drug release was found to follow zero order fashion. The release rate decreased with the increased film thickness and was not affected by the compression force or porosity. The tablets coated to 3% and 4% levels exhibited the release rates within the range calculated from pharmacokinetic data. To illustrate the effect of osmogent content, the tablets were prepared at four osmogent levels and compressed at a constant compression force. The core tablets were coated to a level of 3% wt/wt. The release rate was initially increased with osmogent content and then decreased. At higher osmogent contents, the drug fraction in soluble component was decreased and resulted in the reduction of drug release. In conclusion, film thickness and osmogents played important roles in drug release from EOP tablets.


Asunto(s)
Albuterol/administración & dosificación , Albuterol/química , Broncodilatadores/administración & dosificación , Broncodilatadores/química , Albuterol/farmacocinética , Algoritmos , Disponibilidad Biológica , Broncodilatadores/farmacocinética , Excipientes , Dureza , Rayos Láser , Microscopía Electrónica de Rastreo , Presión Osmótica , Porosidad , Presión , Solubilidad , Comprimidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...