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1.
Biosci Biotechnol Biochem ; 87(1): 82-89, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36255397

RESUMO

The parameter α was obtained from the molar fraction of solute and the freezing points of sugar alcohols and their related sugars in water. For comparison with this parameter, simple measurement of the hydration parameter h was performed using a capillary viscometer and a density meter. This parameter was calculated from the viscosity B coefficient and the partial molar volume of solute. The viscosity B coefficient was more suitable than the partial molar volume for h calculation, as indicated by the determination coefficients of the linear regression lines. h correlated well with α for various compounds, including sugar alcohols in water, supporting the parameters' theoretical correspondence (α =-h). In addition, the activation energy required for hydration implies that the thermal stability increases with the saccharide molecular weight.

2.
Food Chem ; 190: 594-598, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26213015

RESUMO

The hydration parameter h was obtained from the viscosity B-coefficients and the partial molar volume of solute, V2, for various sugars and urea in aqueous solutions. The parameter h showed a good correlation with the parameter α, determined from the activity coefficient of water, representing the solute-solvent interaction. The parameter h also showed a good correlation with the number of equatorial-OH groups (e-OH) for sugars, suggesting that the sugar molecules with the higher e-OH fit more to the water-structure. From the temperature dependence of the parameter h (dh/dT), the negative dh/dT for sugars suggested their water-structure making activity while the positive dh/dT for urea corresponded to its structure breaking effect. From the Arrhenius plot, the activation energy for h, Ea, was determined to be as low as 10 kJ/mol for disaccharides suggesting the stable hydration structure. The Ea increased with a decrease in molecular weight for sugars.


Assuntos
Carboidratos/química , Solventes/química , Soluções , Viscosidade
3.
J Oleo Sci ; 64(6): 653-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25891111

RESUMO

Nursing care food, made smooth and soft by adding a substantial amount of water, has been provided to elderly people who exhibit a decline in chewing and swallowing function. However, this is associated with problems such as an increase in the volume of meals and a decrease in the nutritional value per unit weight, causing malnutrition. To resolve these issues, we aimed to develop gelatinous fat suitable for processing nursing care food. We compared several types of oil and fat including this gelatinous fat using rheology measurement and sensory evaluation. In the measurement of fat alone using a dynamic viscoelastometer, the gelatinous fat had the highest values of storage elastic modulus (G') and loss elastic modulus (G") at the predetermined ranges of temperature and frequency. In the measurement of fat mixed with food using a creep meter, the gelatinous fat showed a significantly lower level of firmness and a higher level of cohesiveness than other types of fat. In the sensory evaluation, food processed with gelatinous fat was evaluated to be better than food processed with no addition or the addition of another type of fat in terms of softness, smoothness, low feeling of residual food, and palatability. These results suggest that the newly developed gelatinous fat is most suitable for nursing care food processing among the types of fat examined. It is expected that nursing care food processed with gelatinous fat can facilitate the consumption of food with high energy and reduce the risk of malnutrition in the elderly.


Assuntos
Gorduras na Dieta , Qualidade dos Alimentos , Alimentos Especializados , Cuidados de Enfermagem , Elasticidade , Gorduras/química , Géis , Desnutrição Proteico-Calórica/prevenção & controle , Temperatura de Transição , Viscosidade
4.
Phys Rev Lett ; 96(9): 093002, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16606260

RESUMO

The quantum interference of two molecular wave packets has been precisely controlled in the B electronic state of the I2 molecule by using a pair of fs laser pulses whose relative phase is locked within the attosecond time scale and its real-time evolution has been observed by another fs laser pulse. It is clearly observed that the temporal evolution changes drastically as a function of the relative phase between the locked pulses, allowing us to read both amplitude and phase information stored in the wave functions of the molecular ensemble.

5.
Phys Rev Lett ; 91(24): 243003, 2003 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-14683114

RESUMO

Molecular wave-packet (WP) interferometry has been demonstrated in the A electronic state of the HgAr van der Waals complex with two time-delayed UV fs pulses at 254 nm. The interferograms of three vibrational levels in the WP's display almost 100% fringe contrast as a function of the interpulse delay tau, which is tuned with sub-10 as stability and resolution. It is clearly observed that the three interferograms show their dephasing and rephasing within a single vibrational period, allowing us to prepare arbitrary relative populations of the three levels by adjusting a single parameter tau.

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