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61.
In the paper, the method of obtaining the potato starch nanocomposites plasticized with a deep eutectic solvent is described. The deep eutectic solvent based on choline chloride and malic acid (CM, molar ratio 1:1) was used as the plasticizer. The effect of the sodium and calcium montmorillonite (MMTNa, MMTCa respectively) addition on the properties of potato starch films was investigated. The thermal, mechanical, and barrier properties were determined. Moreover, a moisture absorption test was performed. The starch gelatinization temperature increased in the presence of montmorillonite. The values of glass transition determined by DMTA depended on the nanofiller type. For the systems containing MMTCa, they generally decreased with its content (although still lower than reference samples). The obtained nanocomposites showed improved mechanical and barrier properties. The highest values of tensile strength and Young’s modulus were noted for the system containing 1% MMTNa. The XRD revealed that only the films with MMTNa exhibited intercalation. The homogeneity of the samples decreased with increasing nanofiller concentration. This was probably due to the occurrence of choline chloride-montmorillonite interactions, which were more favored than clay-starch interactions. 相似文献
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Emilia Janiszewska Dorota Witrowa‐Rajchert 《International Journal of Food Science & Technology》2009,44(12):2438-2444
The influence of particle morphology of spray dried powders obtained by using different carriers on the efficiency of microencapsulation of rosemary aroma is shown in the present research. It was found that the type of the carrier influenced the size but not the shape of rosemary aroma capsules and all the capsules were spherical with cracks. The biggest particles, d50 = 55 μm, were obtained with 25% maltodextrin (MD) as a carrier, and the smallest, d50 = 29 μm with 30% gum arabic (GA). The efficiency of encapsulating aroma inside of the capsules depended on the particles size and apparent density. An increase in the quantity of microencapsulated aroma from 10% for 25% MD to about 60% for 30% GA as the carrier was seen, which co‐related with a decrease in the average diameter of the powder particles. Similarly, an increase in the efficiency of aroma retention was followed by an increase of apparent density of powders from 796 (25% MD) to 1156 kg m?3 (30% GA). 相似文献
65.
Rare earth complexes with trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (DCTA) of the Ln(dcta)- ype exhibited an unusual sequence of affinity on the polystyrene anion exchangers: pm3 >Nd3 >Sm3 >pr3 >Ce3 >Eu3 >Gd3 >La3 >Sc3 >Tb3 >Dy3 >Ho3 >y3 >Er3 >Tm3 >yb3 >Lu3 [1]. Taking into account the position of Y3 , Sm3 , and Nd3 in this affinity series, for the monodispersive polystyrene anion exchangers, Lewafit MonoPlus M 500, Lewatit MonoPlus M 600, Lewatit MonoPlus MP 500, Lewatit MonoPlus MP 64,and for the heterodispersive anion exchanger, Lewatit MP 62, the weight (Dg,) and bed (Dv) distribution coefficients of these complexes and working ion exchange capacities (Cw) were determined. Based on these values, purifications of Y3 from Nd3 and y3 from Sm3 in the macro-micro component system on these anion exchangers were studied. The application potential of this method was highlighted for the separation of yz3 in the presence of Nd3 and Sm3 . With 1 L of monodispersive and strongly basic polystyrene gel anion exchanger Lewatit MonoPlus M 500 in the acetate form, it is possible to obtain approximately 79 g Y2O3 purified from Nd2O3 and 70 g Y2O3 purified from Sm2O3 in the same process condition. 相似文献
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The general parameters of the electrokinetic systems porous Al2O3/polar liquids: acetone, acetonitrile, nitromethane and their binary mixtures have been investigated. 相似文献
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The antioxidant properties of alcoholic extracts from the leaves, berries and flowers of Sambucus nigra L. are estimated by means of DPPH and β-carotene/linoleic acid methods, and considered in relation to the extraction temperature (in the range 20-200 °C) and to the level of flavonoids most representative for this plant. The extracts of S. nigra act as antioxidants neutralizing the activities of free radicals and inhibiting the co-oxidation reactions of linoleic acid and β-carotene. There is no direct correlation between the level of flavonoids in the extracts and their antioxidant activity. The data presented show that the extraction temperature strongly influences the antioxidant properties of the extracts, especially in the case of leaves. 相似文献
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Monika Mieszczakowska-Frąc Barbara Dyki Dorota Konopacka 《Food and Bioprocess Technology》2016,9(3):543-552
The effect of sonication time and kind of liquid medium on polyphenol retention and microstructure changes during predrying treatment of apple tissue was investigated. The apple cubes from ‘Idared’ cultivar were submerged in water or sucrose solution and sonicated indirectly in beakers placed in a water bath fitted with ultrasound transducers (25 kHz, 0.1 W/cm3) at 40 °C. The treatment was conducted with and without ultrasound applied for 45 and 90 min. The content of individual polyphenols was monitored by a reverse-phase high-performance liquid chromatography (RP-HPLC) method. The dominant phenolic compounds in apple were procyanidins, accounting for 56 % of total polyphenols. While a significant effect of sonication on mass transfer intensification was observed when the samples were dehydrated in sucrose solution, almost no negative effects of ultrasound application were perceived on polyphenols concentration, except for dimers of catechin. When using ultrasound in water solution, an increase in polyphenol compound losses was noted. Furthermore, the ultrasound energy caused an apple tissue structure modification which additionally affected polyphenol retention during predrying treatment. 相似文献
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