Influence of alternative drying aids on water sorption of spray dried mango mix powders: A thermodynamic approach

Ultrasound assisted extraction of red cabbage and encapsulation by freeze-drying: moisture sorption isotherms and thermodynamic characteristics of encapsulate

In the present study encapsulation of ultrasound assisted red cabbage extract was carried out using four different carrier agents such as maltodextrin, gum arbic, xanthan gum, and gellan gum. Among the four hydrocolloids investigated, maltodextrin was found to have the least destructive effect on anthocyanin content (14.87 mg C3G/g dw), TPC (54.51 ± 0.09 mg GAE/g dw), TFC (19.82 Mg RE/g dw) and antioxidant activity (74.15%) upon freeze-drying. Subsequently a storage study was conducted using maltodextrin as carrier agent at 25-50 °C. The Clausius-Clapeyron equation was used to evaluate the net isosteric heat (qst) of water adsorption. The differential entropy (ΔS) and qst decreased from 82.298 to 38.628 J/mol, and 27.518 kJ/mol to 12.505 kJ/mol, respectively as the moisture content increased from 2 to 14%. The value of isokinetic energy and Gibb's free energy were found to be 364.88 and - 1.596 kJ/mol for freeze dried red cabbage.

Graphical abstract

Dissociative electron attachment to gold(I)-based compounds: 4,5-dichloro-1,3-diethyl-imidazolylidene trifluoromethyl gold(I)

With the use of proton-NMR and powder XRD (XRPD) studies, the suitability of specific Au-focused electron beam induced deposition (FEBID) precursors has been investigated with low electron energy, structure, excited states and resonances, structural crystal modifications, flexibility, and vaporization level. 4,5-Dichloro-1,3-diethyl-imidazolylidene trifluoromethyl gold(I) is a compound that is a uniquely designed precursor to meet the needs of focused electron beam-induced deposition at the nanostructure level, which proves its capability in creating high purity structures, and its growing importance in other AuIm_x and AuCl_nB (where x and n are the number of radicals, B = CH, CH₃, or Br) compounds in the radiation cancer therapy increases the efforts to design more suitable bonds in processes of SEM (scanning electron microscopy) deposition and in gas-phase studies. The investigation performed of its powder shape using the XRPD XPERT³ panalytical diffractometer based on CoK_α lines shows changes to its structure with change in temperature, level of vacuum, and light; the sensitivity of this compound makes it highly interesting in particular to the radiation research. Used in FEBID, though its smaller number of C, H, and O atoms has lower levels of C contamination in the structures and on the surface, it replaces these bonds with C-Cl and C-N bonds that have lower bond-breaking energy. However, it still needs an extra purification step in the deposition process, either H₂O, O₂, or H jets.

Soft computing modelling of moisture sorption isotherms of milk-foxtail millet powder and determination of thermodynamic properties

Moisture sorption isotherms of spray-dried milk-foxtail millet powder were determined at 10, 25 and 40 °C. Sorption data was fitted using classical and soft-computing approaches. The isotherms were of type II, and equilibrium moisture content (EMC) was temperature dependent. The BET monolayer moisture content decreased from 3.30 to 2.67 % as temperature increased from 10 to 40 °C. Amongst the classical models, Ferro-Fontan gave the best fit of EMC-aw data. However, the Sugeno-type adaptive neuro-fuzzy inference system (ANFIS) with generalized bell-shaped membership function performed better than artificial neural network and classical models with RMSE as low as 0.0099. The isosteric heat of sorption decreased from 150.32 kJ mol(-1) at 1 % moisture content to 44.11 kJ mol(-1) at 15 % moisture. The enthalpy-entropy compensation theory was validated, and the isokinetic and harmonic mean temperatures were determined as 333.1 and 297.5 K, respectively.