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Abstract: Soy hypocotyls, the byproduct from soy protein industry, rich in isoflavones, was attempted to develop into a value-added functional food, soy protein isolate (SPI). Soy hypocotyls were defatted by supercritical CO2 (SC-CO2) under the following conditions as 35MPa, 2h, 45°C with a constant flow rate of CO2 at 5l/min, fed from the bottom of the extraction vessel. Via extraction, the oil contents were lowered from 10.5g/100g in original soy hypocotyls to 0.2g/100g in defatted soy hypocotyls (DSH) with a Protein Dispersibility Index (PDI) value of 91.2 that contained about 2.18g/100g of isoflavones and 63.6g/100g of proteins. SPI was then extracted from DSH under the optimized conditions including: the pH of water solution at 6, the ratio of DSH to water solution as 1:10 and the extraction temperature at 30°C with the extraction time of 30min. The freeze-dried SPI contained 92.46g/100g of the proteins and 640mg/100g of isoflavones, where the three major β-glycosides, glycitin, daidzin and genistin accounted for about 83.7% of the total isoflavones. The yields of SPI and isoflavones were about 48% and 30% in terms of their respective total contents in DSH. [Copyright &y& Elsevier]

Low-temperature heat capacities of pyrimethanil laurate (C24H37N3O2) were precisely measured with an automated adiabatic calorimeter over the temperature range between T=78 K and T=340 K. The sample was observed to melt at (321.52±0.04) K. The molar enthalpy and entropy of fusion as well as the chemical purity of the compound were determined to be (67244±11) J·mol−1, (209.28±0.02) J·mol−1·K−1, (0.9943±0.0004) mass fraction, respectively. The extrapolated melting temperature for the absolutely pure compound obtained from fractional melting experiments was (322.264±0.006) K. [Copyright &y& Elsevier]

Pyrimethanil myristic salt was synthesized and its heat capacities were measured with an automated adiabatic calorimeter over the temperature range from T=(79 to 360) K.The melting point, molar enthalpy, ΔfusHm and entropy, ΔfusSm, of fusion of this compound were determined to be (321.84 ± 0.05) K, (56.53 ± 0.03) kJ · mol−1 and (175.64 ± 0.05) J · mol−1 · K−1, respectively. The purity of the compound was calculated to be 98.99 mol% by using the fractional melting technique. The thermodynamic functions relative to the reference temperature, T=298.15 K, were calculated based on the heat capacity measurements in the temperature ranges from T=(80 to 360) K. The TG-DTG results demonstrate that the mass loss of the sample takes place in one step with the maximum rate at T=500 K, which was caused by evaporation of the sample. [Copyright &y& Elsevier]

The molar heat capacities of 1-(2-hydroxy-3-chloropropyl)-2-methyl-5-nitroimidazole (Ornidazole) (C7H10ClN3O3) with purity of 99.72 mol% were measured with an adiabatic calorimeter in the temperature range between 79 and 380 K. The melting-point temperature, molar enthalpy, ΔfusHm, and entropy, ΔfusSm, of fusion of this compound were determined to be 358.59±0.04 K, 21.38±0.02 kJ mol−1 and 59.61±0.05 J K−1 mol−1, respectively, from fractional melting experiments. The thermodynamic function data relative to the reference temperature (298.15 K) were calculated based on the heat capacities measurements in the temperature range from 80 to 380 K. The thermal stability of the compound was further investigated by DSC and TG. From the DSC curve an intensive exothermic peak assigned to the thermal decomposition of the compound was observed in the range of 445–590 K with the peak temperature of 505 K. Subsequently, a slow exothermic effect appears when the temperature is higher than 590 K, which is probably due to the further decomposition of the compound. The TG curve indicates the mass loss of the sample starts at about 440 K, which corresponds to the decomposition of the sample. [Copyright &y& Elsevier]

Low-temperature heat capacities of the 9-fluorenemethanol (C14H12O) have been precisely measured with a small sample automatic adiabatic calorimeter over the temperature range between T=78 K and T=390 K. The solid–liquid phase transition of the compound has been observed to be Tfus=(376.567±0.012) K from the heat-capacity measurements. The molar enthalpy and entropy of the melting of the substance were determined to be ΔfusHm=(26.273±0.013) kJ · mol−1 and ΔfusSm=(69.770±0.035) J · K−1 · mol−1. The experimental values of molar heat capacities in solid and liquid regions have been fitted to two polynomial equations by the least squares method. The constant-volume energy and standard molar enthalpy of combustion of the compound have been determined, ΔcU(C14H12O, s)=−(7125.56 ± 4.62) kJ · mol−1 and ΔcHm∘(C14H12O, s)=−(7131.76 ± 4.62) kJ · mol−1, by means of a homemade precision oxygen-bomb combustion calorimeter at T=(298.15±0.001) K. The standard molar enthalpy of formation of the compound has been derived, ΔfHm∘(C14H12O,s)=−(92.36 ± 0.97) kJ · mol−1, from the standard molar enthalpy of combustion of the compound in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle. [Copyright &y& Elsevier]

The ability of immobilized lipase B from Candida antarctica (Novozym 435) to catalyze the direct esterification of glyceryl ferulate (FG) and oleic acid for feruloylated monoacylglycerols (FMAG) preparation in a solvent-free system was investigated. Enzyme screening and the effect of glycerol on the initial reaction rate of esterification were also investigated. Response surface methodology (RSM) was used to optimize the effects of the reaction temperature (55-65 degrees C), the enzyme load (8-14%; relative to the weight of total substrates), oleic acid/(FG + glycerol) (6:1-9:1; w/w), and the reaction time (1-2 h) on the conversion of FG and yield of FMAG. Validation of the RSM model was verified by the good agreement between the experimental and the predicted values of FG conversion and FMAG yield. The optimum preparation conditions were as follows: temperature, 60 degrees C; enzyme load, 8.2%; substrate ratio, 8.65:1 (oleic acid/(FG + glycerol), w/w); and reaction time, 1.8 h. Under these conditions, the conversion of FG and yield of FMAG are 96.7 +/- 1.0% and 87.6 +/- 1.2%, respectively.

There are four different types of molecules of hydroxyl groups of the natural attapulgite. The band at 3614 cm(-1) was attributed to the stretching modes of hydroxyls coordinated with the magnesium. The band at 3415 cm(-1) is associated with the hydroxyl stretching vibrations of absorbed water. The bands at 3581 and 3552 cm(-1) were attributed to the symmetric and antisymmetric stretching modes of molecular water coordinated with the magnesium at the edges of the channels. The band at 1653 cm(-1) is associated with the hydroxyl stretching vibrations of zeolitic water. The structures of the natural palygorskite and its products dried at different temperatures for 30 min were analysed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The absorbed, zeolitic and co-ordinated water decreased during the drying process at the same time. The absorbed water was completely-dehydrated firstly, then the zeolitic water, and lastly the co-ordinated water. And the hydroxyl groups remained until about 600 degrees C. When the co-ordinated water was dehydrated completely at 450 degrees C, the crystalloid was destroyed. The mechanism of the palygorskite structure change was also discussed in detail.