The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
Fatemeh Alizadeh - One of the best experts on this subject based on the ideXlab platform.
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measurement and modelling of water activity of aqueous poly ethylene glycol or poly propylene glycol Sodium Potassium Tartrate and corresponding binary salt solutions
The Journal of Chemical Thermodynamics, 2016Co-Authors: Mohammed Taghi Zafaranimoattar, Behnaz Asadzadeh, Fatemeh AlizadehAbstract:Abstract Water activity values of ternary aqueous Sodium Potassium Tartrate (Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol) solutions were measured using the isopiestic method at T = 298.15 K. Also the water activity for corresponding binary aqueous Sodium Potassium Tartrate (Na–K Tar) solutions was measured at T = (298.15, 308.15, 318.15) K. The obtained water activity values for binary aqueous Sodium Potassium Tartrate (Na–K Tar) system were successfully fitted with the local composition and Pitzer models. The mean activity coefficients for the studied binary salt solutions have been calculated. The thermodynamic behaviour of aqueous {(Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol)} solutions was discussed on basis of water, polymer and salt interactions.
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Measurement and modelling of water activity of aqueous poly (ethylene glycol) or poly (propylene glycol) + Sodium Potassium Tartrate and corresponding binary salt solutions
The Journal of Chemical Thermodynamics, 2016Co-Authors: Mohammed Taghi Zafarani-moattar, Behnaz Asadzadeh, Fatemeh AlizadehAbstract:Abstract Water activity values of ternary aqueous Sodium Potassium Tartrate (Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol) solutions were measured using the isopiestic method at T = 298.15 K. Also the water activity for corresponding binary aqueous Sodium Potassium Tartrate (Na–K Tar) solutions was measured at T = (298.15, 308.15, 318.15) K. The obtained water activity values for binary aqueous Sodium Potassium Tartrate (Na–K Tar) system were successfully fitted with the local composition and Pitzer models. The mean activity coefficients for the studied binary salt solutions have been calculated. The thermodynamic behaviour of aqueous {(Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol)} solutions was discussed on basis of water, polymer and salt interactions.
Dimitris P. Makris - One of the best experts on this subject based on the ideXlab platform.
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Ultrasound-Assisted Extraction of Polyphenolic Antioxidants from Olive (Olea europaea) Leaves Using a Novel Glycerol/Sodium-Potassium Tartrate Low-Transition Temperature Mixture (LTTM)
Environments, 2017Co-Authors: Marianna Dedousi, Valentina Mamoudaki, Spyros Grigorakis, Dimitris P. MakrisAbstract:Olive leaves (OLL) represent a major waste generated during the production of olive oil, but there is a great potential for their valorization, because they provide important content in polyphenolic phytochemicals, which possess several bioactivities. In spite of the high number of studies dealing with polyphenol recovery from olive leaves, green processes involving environmentally benign solvents are scarce. In this study, a novel renewable natural low-transition temperature mixture (LTTM), composed of glycerol and Sodium-Potassium Tartrate, was tested for its efficient ability to extract polyphenolic substances from OLL. The extraction process was optimised by using response surface methodology and the maximum yield in total polyphenols was 26.75 ± 3.22 mg caffeic acid equivalents per g dry weight, achieved with 50% (v/v) aqueous LTTM, liquid-to-solid ratio of 45 mL g−1 and at 73 °C. The LTTM was proven to be equally effective with 60% aqueous methanol, but it displayed inferior antioxidant properties. Liquid chromatography-diode array-mass spectrometry analyses revealed no significant qualitative differences between the LTTM and the aqueous methanolic extract.
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ultrasound assisted extraction of polyphenolic antioxidants from olive olea europaea leaves using a novel glycerol Sodium Potassium Tartrate low transition temperature mixture lttm
Environments, 2017Co-Authors: Marianna Dedousi, Valentina Mamoudaki, Spyros Grigorakis, Dimitris P. MakrisAbstract:Olive leaves (OLL) represent a major waste generated during the production of olive oil, but there is a great potential for their valorization, because they provide important content in polyphenolic phytochemicals, which possess several bioactivities. In spite of the high number of studies dealing with polyphenol recovery from olive leaves, green processes involving environmentally benign solvents are scarce. In this study, a novel renewable natural low-transition temperature mixture (LTTM), composed of glycerol and Sodium-Potassium Tartrate, was tested for its efficient ability to extract polyphenolic substances from OLL. The extraction process was optimised by using response surface methodology and the maximum yield in total polyphenols was 26.75 ± 3.22 mg caffeic acid equivalents per g dry weight, achieved with 50% (v/v) aqueous LTTM, liquid-to-solid ratio of 45 mL g−1 and at 73 °C. The LTTM was proven to be equally effective with 60% aqueous methanol, but it displayed inferior antioxidant properties. Liquid chromatography-diode array-mass spectrometry analyses revealed no significant qualitative differences between the LTTM and the aqueous methanolic extract.
M. Haris - One of the best experts on this subject based on the ideXlab platform.
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Thermal, magnetic, dielectric and anti microbial properties of solution-grown pure and doped Sodium Potassium Tartrate crystals
Optik, 2016Co-Authors: V. Mathivanan, M. Haris, J. ChandrasekaranAbstract:Abstract Crystals of pure and Cu(NO3)2·3H2O doped Rochelle salt (Sodium Potassium Tartrate) crystals are grown from solution at room temperature. The thermal studies such as TGA (thermo gravimetric analysis) shows that there are four stages of decomposition which is confirmed through the four endothermic peaks found in the DSC (differential scanning calorimetry) curve for both pure and Cu(NO3)2·3H2O doped Rochelle salt crystals. The magnetic susceptibility of the pure and doped crystals were found out to be 42.483 × 10−6 and 40.29 × 10−6 emu, respectively. Similarly, the magnetic moment of pure and doped crystals have been found out to be 3.19 BM and 3.10 BM, respectively. The antimicrobial activity of Pure and Cu(NO3)2·3H2O doped Rochelle salt crystals for various concentrations are explained in detail. The dielectric constant of pure and doped crystal decreases as the frequency of applied field increases at the end it gives diminishing value of dielectric constant. The dielectric nature of pure and doped crystals have been compared. The antimicrobial activity of pure and doped crystals shows the inhibition zone diameter for various concentrations with respect to E. coli and Staphylococcus aureus.
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Studies on solution-grown pure and doped Sodium Potassium Tartrate crystals
Spectrochimica acta. Part A Molecular and biomolecular spectroscopy, 2012Co-Authors: V. Mathivanan, M. HarisAbstract:Abstract A systematic analysis of the Fourier transform infrared spectroscopy and Raman spectra of pure and Cu(NO3)23H2O doped Rochelle salt (NaKC4H4O64H2O) in terms of the standard frequency correlations, deuteration shift and typical nature (with respect to intensity and width) of bands due to different modes is reported. The bands due to the internal modes (excluding some skeletal modes) of the C 4 H 4 O 6 2 - ion appear as doublets. For certain modes (e.g. βCH, γC(OH) and δCOO) doublets arise owing to interaction between two identical oscillations of two identical groups in COO(HO)HCCH(OH)COO2−, while for other modes (e.g. γCH, γ CO a , γ CO s , δCOH and τCOO) they arise owing to crystallographically distinguishable sites for two identical oscillators. The effect of dopant in the pure Rochelle salt crystals is found out by using Elemental analysis. The unit cell volume of pure and Cu(NO3)23H2O doped Rochelle salt crystals is found out from powder X-ray diffraction studies.
Marianna Dedousi - One of the best experts on this subject based on the ideXlab platform.
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Ultrasound-Assisted Extraction of Polyphenolic Antioxidants from Olive (Olea europaea) Leaves Using a Novel Glycerol/Sodium-Potassium Tartrate Low-Transition Temperature Mixture (LTTM)
Environments, 2017Co-Authors: Marianna Dedousi, Valentina Mamoudaki, Spyros Grigorakis, Dimitris P. MakrisAbstract:Olive leaves (OLL) represent a major waste generated during the production of olive oil, but there is a great potential for their valorization, because they provide important content in polyphenolic phytochemicals, which possess several bioactivities. In spite of the high number of studies dealing with polyphenol recovery from olive leaves, green processes involving environmentally benign solvents are scarce. In this study, a novel renewable natural low-transition temperature mixture (LTTM), composed of glycerol and Sodium-Potassium Tartrate, was tested for its efficient ability to extract polyphenolic substances from OLL. The extraction process was optimised by using response surface methodology and the maximum yield in total polyphenols was 26.75 ± 3.22 mg caffeic acid equivalents per g dry weight, achieved with 50% (v/v) aqueous LTTM, liquid-to-solid ratio of 45 mL g−1 and at 73 °C. The LTTM was proven to be equally effective with 60% aqueous methanol, but it displayed inferior antioxidant properties. Liquid chromatography-diode array-mass spectrometry analyses revealed no significant qualitative differences between the LTTM and the aqueous methanolic extract.
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ultrasound assisted extraction of polyphenolic antioxidants from olive olea europaea leaves using a novel glycerol Sodium Potassium Tartrate low transition temperature mixture lttm
Environments, 2017Co-Authors: Marianna Dedousi, Valentina Mamoudaki, Spyros Grigorakis, Dimitris P. MakrisAbstract:Olive leaves (OLL) represent a major waste generated during the production of olive oil, but there is a great potential for their valorization, because they provide important content in polyphenolic phytochemicals, which possess several bioactivities. In spite of the high number of studies dealing with polyphenol recovery from olive leaves, green processes involving environmentally benign solvents are scarce. In this study, a novel renewable natural low-transition temperature mixture (LTTM), composed of glycerol and Sodium-Potassium Tartrate, was tested for its efficient ability to extract polyphenolic substances from OLL. The extraction process was optimised by using response surface methodology and the maximum yield in total polyphenols was 26.75 ± 3.22 mg caffeic acid equivalents per g dry weight, achieved with 50% (v/v) aqueous LTTM, liquid-to-solid ratio of 45 mL g−1 and at 73 °C. The LTTM was proven to be equally effective with 60% aqueous methanol, but it displayed inferior antioxidant properties. Liquid chromatography-diode array-mass spectrometry analyses revealed no significant qualitative differences between the LTTM and the aqueous methanolic extract.
Behnaz Asadzadeh - One of the best experts on this subject based on the ideXlab platform.
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measurement and modelling of water activity of aqueous poly ethylene glycol or poly propylene glycol Sodium Potassium Tartrate and corresponding binary salt solutions
The Journal of Chemical Thermodynamics, 2016Co-Authors: Mohammed Taghi Zafaranimoattar, Behnaz Asadzadeh, Fatemeh AlizadehAbstract:Abstract Water activity values of ternary aqueous Sodium Potassium Tartrate (Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol) solutions were measured using the isopiestic method at T = 298.15 K. Also the water activity for corresponding binary aqueous Sodium Potassium Tartrate (Na–K Tar) solutions was measured at T = (298.15, 308.15, 318.15) K. The obtained water activity values for binary aqueous Sodium Potassium Tartrate (Na–K Tar) system were successfully fitted with the local composition and Pitzer models. The mean activity coefficients for the studied binary salt solutions have been calculated. The thermodynamic behaviour of aqueous {(Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol)} solutions was discussed on basis of water, polymer and salt interactions.
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Measurement and modelling of water activity of aqueous poly (ethylene glycol) or poly (propylene glycol) + Sodium Potassium Tartrate and corresponding binary salt solutions
The Journal of Chemical Thermodynamics, 2016Co-Authors: Mohammed Taghi Zafarani-moattar, Behnaz Asadzadeh, Fatemeh AlizadehAbstract:Abstract Water activity values of ternary aqueous Sodium Potassium Tartrate (Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol) solutions were measured using the isopiestic method at T = 298.15 K. Also the water activity for corresponding binary aqueous Sodium Potassium Tartrate (Na–K Tar) solutions was measured at T = (298.15, 308.15, 318.15) K. The obtained water activity values for binary aqueous Sodium Potassium Tartrate (Na–K Tar) system were successfully fitted with the local composition and Pitzer models. The mean activity coefficients for the studied binary salt solutions have been calculated. The thermodynamic behaviour of aqueous {(Na–K Tar) + poly (ethylene glycol) or poly (propylene glycol)} solutions was discussed on basis of water, polymer and salt interactions.