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Unsaturated fat replacement should be used to reduce the use of saturated fat and trans fatty acids in the diet. In this study, pea protein micro-gels (PPMs) with different structures were prepared by microparticulation at pH 4.0–7.0 and named as PPM (pH 4.0), PPM (pH 4.5), PPM (pH 5.0), PPM (pH 5.5), PPM (pH 6.0), PPM (pH 6.5), and PPM (pH 7.0). Pea protein was used as a control to evaluate the structure and interfacial properties of PPMs by particle size distribution, Fourier transform infrared spectroscopy (FTIR), free sulfhydryl group content, and emulsifying property. PPM (pH 7.0) was suitable for application in O/W emulsion stabilization because of its proper particle size, more flexible structure, high emulsifying activity index (EAI) and emulsifying stability index (ESI). The Pickering emulsion stabilized by PPM (pH 7.0) had a uniform oil droplet distribution and similar rheological properties to cream, so it can be used as a saturated fat replacement in the manufacture of ice cream. Saturated fat was partially replaced at different levels of 0%, 20%, 40%, 60%, 80%, and 100%, which were respectively named as PR0, PR20, PR40, PR60, PR80, and PR100. The rheological properties, physicochemical indexes, and sensory properties of low-saturated fat ice cream show that PPM (pH 7.0)-stabilized emulsion can be used to substitute 60% cream to manufacture low-saturated fat ice cream that has high structural stability and similar melting properties, overrun, and sensory properties to PR0. The article shows that it is feasible to prepare low-saturated fat ice cream with PPM (pH 7.0)-stabilized Pickering emulsion, which can not only maintain the fatty acid profile of the corn oil used, but also possess a solid-like structure. Its application is of positive significance for the development of nutritious and healthy foods and the reduction of chronic disease incidence. [ABSTRACT FROM AUTHOR]

In order to acquire a red light-emitting component for an efficient w-LEDs device, we synthesized a series of Eu3+-doped Sr2GaTaO6 (SGT) phosphors using a traditional high-temperature solid-phase technique. The results of UV diffuse reflectance proved that the SGT host possesses a broad optical energy bandgap (Egap) of 4.47 eV (calculated value). The relevant characteristic spectra were also tested. By monitoring the emission at 612 nm, the excitation peak at 466 nm matches the blue light region (460–470 nm) of the popular blue LED chips on the market. The photoluminescence (PL) spectra of SGT: Eu3+ phosphors at room temperature consisting of four obvious PL bands (5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3, and 5D0 → 7F4) in the visible range. And the PL properties are necessarily analyzed by fluorescence decay curves. And it exhibits a decent photoluminescence quantum yield (39.88%). Moreover, the color purity and the ∆E of the SGT: 0.2Eu3+ sample are 96.5% and 0.29 eV, respectively, demonstrating that the ∆E of SGT: Eu3+ phosphor is superior to other reported Eu3+-doped materials for w-LEDs applications. The results manifest that the Eu3+ doped SGT phosphors can be outstanding candidates for w-LEDs applications with high color purity and activation energy. [ABSTRACT FROM AUTHOR]

Due to its poor stability and rapid metabolism, the biological activity and absorption of epigallocatechin gallate (EGCG) is limited. In this work, EGCG-loaded bovine serum albumin (BSA)/pullulan (PUL) nanoparticles (BPENs) were successfully fabricated via self-assembly. This assembly was driven by hydrogen bonding, which provided the desired EGCG loading efficiency, high stability, and a strong antioxidant capacity. The encapsulation efficiency of the BPENs was above 99.0%. BPENs have high antioxidant activity in vitro, and, in this study, their antioxidant capacity increased with an increase in the EGCG concentration. The in vitro release assays showed that the BPENs were released continuously over 6 h. The Fourier transform infrared spectra (FTIR) analysis indicated the presence of hydrogen bonding, hydrophobic interactions, and electrostatic interactions, which were the driving forces for the formation of the EGCG carrier nanoparticles. Furthermore, the transmission electron microscope (TEM) images demonstrated that the BSA/PUL-based nanoparticles (BPNs) and BPENs both exhibited regular spherical particles. In conclusion, BPENs are good delivery carriers for enhancing the stability and antioxidant activity of EGCG. [ABSTRACT FROM AUTHOR]

Chitosan (CS) and pea protein isolate (PPI) were used as raw materials to prepare nanoparticles. The structures and functional properties of the nanoparticles with three ratios (1:1, 1:2 1:3, CS:PPI) were evaluated. The particle sizes of chitosan–pea protein isolate (CS–PPI) nanoparticles with the ratios of 1:1, 1:2, and 1:3 were 802.95 ± 71.94, 807.10 ± 86.22, and 767.75 ± 110.10 nm, respectively, and there were no significant differences. Through the analysis of turbidity, endogenous fluorescence spectroscopy and Fourier transform infrared spectroscopy, the interaction between CS and PPI was mainly caused by electrostatic mutual attraction and hydrogen bonding. In terms of interface properties, the contact angles of nanoparticles with the ratio of 1:1, 1:2, and 1:3 were 119.2°, 112.3°, and 107.0°, respectively. The emulsifying activity (EAI) of the nanoparticles was related to the proportion of protein. The nanoparticle with the ratio of 1:1 had the highest potential and the best thermal stability. From the observation of their morphology by transmission electron microscopy, it could be seen that the nanoparticles with a ratio of 1:3 were the closest to spherical. This study provides a theoretical basis for the design of CS–PPI nanoparticles and their applications in promoting emulsion stabilization and the delivery of active substances using emulsions. [ABSTRACT FROM AUTHOR]

Purpose: Based on the nonlocal elasticity theory, the vibration behavior and wave propagation of functionally graded Euler nanobeams with axial motion are investigated. Assuming that the axial velocity of nanobeams is a constant and the graded material parameters vary along the thickness direction in terms of power index, we apply the hypothesis of neutral plane to derive the axial displacement of geometry surface caused by non-uniformity of graded materials. Effects of graded index, axial velocity and nonlocal scale parameter on natural frequencies are analyzed through numerical examples. Also, the relationship between wave propagation frequency, wave velocity and wave number is revealed. Methods: The complex mode method is utilized to solve the governing equation, and the natural frequencies and wave velocity are obtained accordingly. To solve the derived transcendental equations, the Newton iteration method is used and a detailed solution flowchart is provided. Results and Conclusions: For vibration, with the increase of non-dimensional axial velocity, non-dimensional nonlocal parameter and gradient index, natural frequencies decrease. For wave propagation, with the increase of wave number, frequency of wave propagation increases. However, with the increase of wave number, velocity of wave propagation decreases. Moreover, increasing the gradient index causes a decrease in frequency and velocity of wave propagation, increasing the axial velocity causes an increase in frequency and velocity of wave propagation, and increasing the nonlocal parameter causes a decrease in frequency and velocity of wave propagation. [ABSTRACT FROM AUTHOR]

A series of single-phase Sr3YNa(PO4)3F:Dy3+ phosphors were successfully synthesized via a conventional solid state reaction process. The powder X-ray diffraction patterns were utilized to confirm the phase composite and crystal structure. The phosphor could be excited by the ultraviolet visible light in the region from 300 to 420 nm, and it shown two dominant emission bands peaking at 484 nm (blue light) and 580 nm (yellow light) which originated from the transitions of 4F9/2→6H15/2 and 4F9/2→6H13/2 of Dy3+, respectively. The optimum dopant concentration of Dy3+ ions was confirmed to be 7 mol% in Sr3YNa(PO4)3F:Dy3+ system and the concentration quenching mechanism is dipole-dipole interaction. The lifetime values of Dy3+ ions at different concentrations (x = 0.03, 0.05, 0.07, 0.09 and 0.11) were determined to be about 0.855, 0.759, 0.686, 0.606 and 0.546 ms, respectively. The thermal stability of luminescence of Sr3YNa(PO4)3F:0.07Dy3+ phosphor was also investigated and the activated energy was deduced to be 0.228 eV, which shows good thermal stability. The chromaticity coordinates fall in the white-light region calculated by the emission spectrum. These results show that Sr3YNa(PO4)3F:Dy3+ phosphor can be a promising white emitting phosphor for white LEDs. [ABSTRACT FROM AUTHOR]

Phase pure Ce3+ and Tb3+ singly doped and Ce3+/Tb3+ co-doped Ba3GdNa(PO4)3F samples have been synthesized via the high temperature solid-state reaction. The crystal structures, photoluminescence properties, fluorescence lifetimes, thermal properties and energy transfer of Ba3GdNa(PO4)3F:Ce3+,Tb3+ were systematically investigated. Rietveld structure refinement indicates that Ba3GdNa(PO4)3F crystallizes in a hexagonal crystal system with the space group P-6. For the co-doped Ba3GdNa(PO4)3F:Ce3+,Tb3+ samples, the emission color can be tuned from blue to green by varying the doping concentration of the Tb3+ ions. The intense green emission was realized in the Ba3GdNa(PO4)3F:Ce3+,Tb3+ phosphors on the basis of the highly efficient energy transfer from Ce3+ to Tb3+. Also the energy transfer mechanism has been confirmed to be quadrupole-quadrupole interaction, which can be validated via the agreement of critical distances obtained from the concentration quenching (13.84 Å). These results show that the developed phosphors may possess potential applications in near-ultraviolet pumped white light-emitting diodes. [ABSTRACT FROM AUTHOR]

Highly-ordered ridged TiO nanotube (TNT) arrays have been fabricated by a simple anodic method. Their structures have been systematically investigated using X-ray diffractometer, scanning electron microscope, energy dispersive spectrometer and HRTEM, and the results clearly presented the ridged morphologies with the outer diameters of about 200 nm. We also found that the annealing procedure induced the phase transformation from amorphous phase to anatase phase. The room-temperature photoluminescence (PL) properties were studied, and the much stronger PL emission for the anatase phase was observed compared to the amorphous counterparts. Furthermore, the broad emission for the anatase phase could be decomposed of three peaks locating at 540, 622 and 773 nm, respectively. The oxygen vacancies and the trapping of free excitons by TiO octahedra near defects are the key factors to cause these peaks. [ABSTRACT FROM AUTHOR]

Appropriate pretreatment of proteins and addition of xanthan gum (XG) has the potential to improve the stability of oil-in-water (O/W) emulsions. However, the factors that regulate the enhancement and the mechanism are still not clear, which restricts the realization of improving the emulsion stability by directional design of its structure. Therefore, the effects of whey protein micro-gel particles (WPMPs) and WPMPs-XG complexes on the stability of O/W emulsion were investigated in this article to provide theoretical support. WPMPs with different structures were prepared by pretreatment (controlled high-speed shear treatment of heat-set WPC gels) at pH 3.5–8.5. The impact of initial WPC structure and XG addition on Turbiscan Indexes, mean droplet size and the peroxide values of O/W emulsions was investigated. The results indicate that WPMPs and XG can respectively inhibit droplet coalescence and gravitational separation to improve the physical stability of WPC-stabilized O/W emulsions. The pretreatment significantly enhanced the oxidative stability of WPC-stabilized O/W emulsions. The addition of XG did not necessarily enhance the oxidative stability of O/W emulsions. Whether the oxidative stability of the O/W emulsion with XG is increased or decreased depends on the interface structure of the protein-XG complex. This study has significant implications for the development of novel structures containing lipid phases that are susceptible to oxidation. [ABSTRACT FROM AUTHOR]