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Your search keyword '"Díaz-Torres, Raúl"' showing total 9 results
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9 results on '"Díaz-Torres, Raúl"'

2. Improving spin crossover characteristics in heteroleptic [FeIII(qsal-5-I)(qsal-5-OMe)]A complexes.

Author

Díaz-Torres, Raúl, Gómez-Coca, Silvia, Ruiz, Eliseo, Harding, Phimphaka, and Harding, David J.

Subjects
*PHENOXIDES, *MAGNETIC properties, *COLLOIDS, *HYSTERESIS, *SPIN crossover
Abstract

A family of heteroleptic spin crossover (SCO) [FeIII(qsal-5-I)(qsal-5-OMe)]A·sol (qsal-5-X = 5-X-2-[(8-quinolylimino)methyl]phenolate; A = NO3−1 sol = 2MeOH, NCS−2 sol = 0.75MeOH·1.3H2O, BF4−3 sol = MeOH, OTf−4, sol = MeOH) complexes have been synthesized. Most of the complexes exhibit gradual SCO, with the exception of NCS, which is principally high spin. In contrast, the OTf complex shows an abrupt hysteretic SCO (35 K) after solvent loss. The magnetic properties of this complex are significantly improved in comparison to the related homoleptics, [Fe(qsal-I)2]OTf 5 (hysteresis, 8 K) and [Fe(qsal-5-OMe)2]OTf·CH2Cl26 (gradual SCO). Structural studies reveal that slight changes in the crystal packing cause stronger interactions improving the cooperativity. These findings are supported by DFT calculations using the r2SCAN functional in which the calculated structures show that SCO from the LS to the HS state causes pronounced scissoring of the 1D π–π chains and substantial changes in their relative orientation following loss of MeOH. [ABSTRACT FROM AUTHOR]

Published
2023
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4. Degradación del ácido ascórbico en néctar de durazno enriquecido

Author

Cedeño Sares, Luis Alberto, Díaz Torres, Raúl, Armijos Cabrera, Gabriela, San Martín Torres, Delly Maribel, and Porras Fernández, Martha Ileana

Subjects
ascorbic acid, storage, kinetics, peach nectar, ácido ascórbico, almacenamiento, cinética, néctar de durazno
Abstract

The objective of this work was to evaluate the effect of processing and storage conditions on the content of ascorbic acid (AA) in a commercial peach nectar, enriched with vitamin C. The total loss of AA during processing was 54.15%, occurring mainly during pasteurization and subsequent cooling. During storage, it was found that AA degradation is dependent on temperature and light exposure. Values of -0.0066, -0.0118 and -0.0171 day-1 were found for the degradation rate constant (k) for storage at 22 °C, without exposure to light; 22 °C, with exposure to light and 45 °C, without exposure to light, respectively., El objetivo de este trabajo fue evaluar el efecto del procesamiento y condiciones de almacenamiento sobre el contenido de ácido ascórbico (AA) en un néctar de durazno comercial, enriquecido con vitamina C. La pérdida total de AA durante el procesamiento fue de 54.15 %, ocurriendo principalmente durante la pasteurización y posterior enfriamiento. Durante el almacenamiento se comprobó que la degradación de AA es dependiente de la temperatura y exposición a la luz. Se encontraron valores para la constante de velocidad de degradación (k) de -0.0066, -0.0118 y -0.0171 dia-1 para el almacenamiento a 22 oC, sin exposición a la luz; 22 oC, con exposición a la luz y 45 oC, sin exposición a la luz, respectivamente.

Published
2022

5. Degradación del ácido ascórbico en néctar de durazno enriquecido

Author

San Martín Torres, Delly Maribel, Porras Fernández, Martha Ileana, Cedeño Sares, Luis A., Díaz Torres, Raúl, Armijos Cabrera, Gabriela, San Martín Torres, Delly Maribel, Porras Fernández, Martha Ileana, Cedeño Sares, Luis A., Díaz Torres, Raúl, and Armijos Cabrera, Gabriela

Abstract

The objective of this work was to evaluate the effect of processing and storage conditions on the content of ascorbic acid (AA) in a commercial peach nectar, enriched with vitamin C. The total loss of AA during processing was 54.15%, occurring mainly during pasteurization and subsequent cooling. During storage, it was found that AA degradation is dependent on temperature and light exposure. Values of -0.0066, -0.0118 and -0.0171 day-1were found for the degradation rate constant (k) for storage at 22 °C, without exposure to light; 22 °C, with exposure to light and 45 °C, without exposure to light, respectively., El objetivo de este trabajo fue evaluar el efecto del procesamiento y condiciones de almacenamiento sobre el contenido de ácido ascórbico (AA) en un néctar de durazno comercial, enriquecido con vitamina C. La pérdida total de AA durante el procesamiento fue de 54.15 %, ocurriendo principalmente durante la pasteurización y posterior enfriamiento. Durante el almacenamiento se comprobó que la degradación de AA es dependiente de la temperatura y exposición a la luz. Se encontraron valores para la constante de velocidad de degradación (k) de -0.0066, -0.0118 y -0.0171 dia-1para el almacenamiento a 22 oC, sin exposición a la luz; 22 oC, con exposición a la luz y 45 oC, sin exposición a la luz, respectivamente.

Published
2022

9. Improving spin crossover characteristics in heteroleptic [Fe III (qsal-5-I)(qsal-5-OMe)]A complexes.

Author

Díaz-Torres R, Gómez-Coca S, Ruiz E, Harding P, and Harding DJ

Abstract

A family of heteroleptic spin crossover (SCO) [Fe III (qsal-5-I)(qsal-5-OMe)]A·sol (qsal-5-X = 5-X-2-[(8-quinolylimino)methyl]phenolate; A = NO 3 - 1 sol = 2MeOH, NCS - 2 sol = 0.75MeOH·1.3H 2 O, BF 4 - 3 sol = MeOH, OTf - 4, sol = MeOH) complexes have been synthesized. Most of the complexes exhibit gradual SCO, with the exception of NCS, which is principally high spin. In contrast, the OTf complex shows an abrupt hysteretic SCO (35 K) after solvent loss. The magnetic properties of this complex are significantly improved in comparison to the related homoleptics, [Fe(qsal-I) 2 ]OTf 5 (hysteresis, 8 K) and [Fe(qsal-5-OMe) 2 ]OTf·CH 2 Cl 2 6 (gradual SCO). Structural studies reveal that slight changes in the crystal packing cause stronger interactions improving the cooperativity. These findings are supported by DFT calculations using the r 2 SCAN functional in which the calculated structures show that SCO from the LS to the HS state causes pronounced scissoring of the 1D π-π chains and substantial changes in their relative orientation following loss of MeOH.

Published
2023
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