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The effects of multi-frequencies (mono: 20 kHz, 40 kHz, 60 kHz; dual: 20/40 kHz, 40/60 kHz, 20/60 kHz, and tri: 20/40/60 kHz) on physicochemical properties and in vitro digestibility of arrowhead starch-linoleic acid (AS-LA) complexes were evaluated. The complexing index and FTIR analyses showed that sonication treatment might be helpful in the formation of AS-LA complexes in an ultrasound frequency-dependent manner. The SEM micrographs revealed that the various ultrasonication frequencies caused dense network structure in AS-LA complexes. The XRD showed a V-type crystalline structure with increased crystallinity. Compared with arrowhead starch, a decrease in rapidly digestible starch , and an increase in resistant starch contents of AS-LA under various ultrasound frequencies was due to arrowhead starch and linoleic acid molecular interactions, which inhibited the further binding abilities. As a non-thermal technology, ultrasound could be effectively employed to prepare starch-lipid complexes with significant potential in functional foods and drug delivery systems.

The effects of ultrasound-assisted enzymolysis on the physicochemical properties and structure of arrowhead-derived type 3 resistant starch (RS3) were investigated. Compared with the traditional enzymolysis, ultrasonic treatment significantly (p

In this study, resveratrol was successfully encapsulated using zein-chitosan complex coacervation. The encapsulation efficiency was markedly improved (51.4%) after chitosan coating at 1:2.5 zein/chitosan ratio, compared with 38.6% using native zein. Analysis of multi-model frequency ultrasound treatment effects on resveratrol encapsulation using zein-chitosan complex coacervation showed that 28/40 kHz dual-frequency ultrasound led to the highest encapsulation efficiency (65.2%; 31.9% increase) and loading capacity (5.9%; 31.1% increase) of resveratrol, followed by multi-frequency ultrasound at 20/28/40 kHz (17.8% encapsulation efficiency increase; 17.8% loading capacity increase). Dual-frequency ultrasound treatment significantly reduced the zein-chitosan complex coacervation particle size and reduced their distribution, however, did not change the zeta potential. Fourier transform infrared spectroscopy and fluorescence spectroscopy analysis demonstrated that ultrasound treatment had no effect on secondary structure of zein-chitosan complex but markedly decreased the fluorescence emission intensity. Differential scanning calorimetry and X-ray diffraction results indicated that Dual-frequency ultrasound treatment improved the thermal stability of zein-chitosan complex coacervation but had no effect on the crystal structure. Atomic force microscopy and scanning electron microscopy images revealed uniform distribution of zein-chitosan complex coacervation followed by ultrasonic treatment.

The main areas of forest in Ningxia Province lie in the Helan and Liupan mountain ranges.These forests have important ecological and economic significance.The fertility of forest soil in these areas has not been systematically studied.The objective of this study was to evaluate soil fertility under six forest types in the Su-Yukou forest zone of the Helan mountain range and in the Xi-Xia and Die-Diegou forest zones of the Liupan mountain range.The natural forest types were Pinus tabulaeformis × Populus davidiana,Picea crassifolia × Populus davidiana,Potentilla parvifolia,and Larix principis-rupprechtii.The planted forest types were Quercus liaotungensis and Larix principis-rupprechtii.Five separate profiles(replications) were sampled in an 'S' pattern for each soil type.The profiles were divided into A,B,and C horizons and then sampled,making a total of 18 soil samples.Soil physical and chemical properties were measured with conventional methods.The results were analyzed using univariate analysis of variance.Differences among forest types and soil horizons were analyzed with Duncan′s test(SSR).Soil fertility characteristics were evaluated using principal component analysis. The results indicated significant differences in soil fertility under the six forest types.These differences can probably be attributed to differences in the accumulation and decomposition of forest litter,in soil parent material,or in climatic conditions.Soil porosity ranged from 54.5 to 72.2% and decreased as soil depth increased.Soil bulk density ranged from 0.72 to 1.21 g/cm3 and particle density ranged from 2.55 to 2.68 g/cm3.Soil bulk density and particle density both increased as soil depth increased.Soil particle density in the Liupan mountains was higher than that in the Helan mountains.Soil organic C(24.03—65.37 g/kg),total N(1.48—3.49 g/kg),NO-3-N(1.88—10.50 mg/kg),NH+4-N(5.02—11.01 mg/kg),total P(0.37—1.19 g/kg),available P(4.82—13.38 mg/kg),and available K(82.03—244.62 mg/kg) increased as soil depth increased.Total K(18.92—26.14 g/kg) increased as soil depth increased.Total K concentrations were higher in soil from the Liupan mountains than in soil from the Helan mountains.The soil C ∶N ratio(11.74 to 19.88) tended to be highest in the B horizon followed by the C and A horizons.The cation exchange capacity(23.94—40.30 cmol/kg) decreased as soil depth increased.In contrast,soil pH(7.09—8.09),exchangeable sodium percentage(0.59%—2.47%) and base saturation percentage(51.24%—80.57%) increased as soil depth increased.Clay content(5.46%—10.20%),total dissolved salt,(0.33—1.12 g/kg),and CaCO3 content(1.44—14.23 g/kg) did not change significantly with soil depth.The soil C ∶N ratio,pH,exchangeable sodium percentage,total dissolved salt,and CaCO3 content of soil from the Helan mountains was higher than that of soil from the Liupan mountains.Factor analysis was used to describe soil fertility under the six forest types.Three soil fertility components(organic matter factor,environmental factor,and NO-3-N factor) were derived from 14 physico-chemical soil properties.Component scores showed significant differences among the three fertility components under different forest types.The soil under the Picea crassifolia × Populus davidiana forest had the highest component score for the organic matter factor.Soils from the Helan mountain range had the highest component score for the environmental factor,and soil from the natural Potentilla parvifolia and Larix principis-rupprechtii forest had the highest component score for the NO-3-N factor.

On the basis of design of experiment and numerical simulation, a reliable optimization method for blades of a mixed-flow pump is proposed with the maximum weighted average efficiency at multi-conditions as optimum objective. First, the performance of the model pump was measured and the test results were used to validate the simulation method. To improve the simulation accuracy, the check of the grid independence and the comparison of different turbulence models were done in detail. Then, the method of design of experiment for key geometrical parameters was used to obtain the optimization scheme. The maximum weighted average efficiency of pump at three operation conditions was chosen as optimum objective. The optimum solution was gotten and confirmed by the experiment. The results demonstrate that efficiency of the mixed-flow pump with optimized impeller increases by 3.9%, and the high-efficiency zone is increased from 0.021 to 0.040.