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This paper deals with the following parabolic-parabolic-parabolic chemotaxis system with singular sensitivity and Lotka-Volterra competition kinetics (0.1) { u t = Δ u − χ 1 ∇ ⋅ (u w ∇ w) + μ 1 u (1 − u − a 1 v) , t > 0 , x ∈ Ω , v t = Δ v − χ 2 ∇ ⋅ (v w ∇ w) + μ 2 v (1 − v − a 2 u) , t > 0 , x ∈ Ω , w t = Δ w − w + u + v , t > 0 , x ∈ Ω , ∂ u ∂ ν = ∂ v ∂ ν = ∂ w ∂ ν = 0 , t > 0 , x ∈ ∂ Ω , u (0 , x) = u 0 (x) , v (0 , x) = v 0 (x) , w (0 , x) = w 0 (x) , x ∈ Ω , where Ω ⊂ R N (N ≥ 2) is a bounded smooth convex domain, and the parameters χ 1 , χ 2 , μ 1 , μ 2 , a 1 and a 2 are positive constants. It is shown that the system possesses globally bounded classical solutions under the following conditions χ 1 , χ 2 ∈ (0 , 1 2) for N = 2 , 3 or χ 1 , χ 2 ∈ (0 , N − 2 N − 1) for N ≥ 4. Moreover, if min ⁡ { μ 1 , μ 2 } > max ⁡ { χ 1 , χ 2 } 2 4 , we obtain the uniformly lower bound for w. Finally, when χ 1 , χ 2 are suitably small, it is proved that if 0 < a 1 , a 2 < 1 , then the solution (u , v , w) converges to (1 − a 1 1 − a 1 a 2 , 1 − a 2 1 − a 1 a 2 , 2 − a 1 − a 2 1 − a 1 a 2 ) in L ∞ norm as t → ∞ ; if 0 < a 2 < 1 ≤ a 1 , then the solution (u , v , w) converges to (0 , 1 , 1) in L ∞ norm as t → ∞. [ABSTRACT FROM AUTHOR]

[Display omitted] • Myofibrillar protein-luteolin vehicle was greenly prepared with a high load capacity. • The differences between ethanol and non-ethanol samples were compared. • Ethanol samples showed superior in vitro antioxidant capacity. • Non-ethanol samples showed superior sustained-release properties. In this study, the highly loaded myofibrillar protein (MP)-luteolin (Lut) complexes were noncovalently constructed by using green high-pressure homogenization technology (HPH) and high-pressure micro-fluidization technology (HPM), aiming to optimize the encapsulation efficiency of flavonoids in the protein-based vehicle without relying on the organic solvent (i.e. DMSO, ethanol, etc.). The loading efficiency of Lut into MPs could reach 100 % with a concentration of 120 μmol/g protein by using HPH (103 MPa, 2 passes) without ethanol adoption. The in vitro gastrointestinal digestion behavior and antioxidant activity of the complexes were then compared with those of ethanol-assisted groups. During gastrointestinal digestion, the MP digestibility of complexes, reaching more than 70.56 % after thermal treatment, was higher than that of sole protein. The release profile of Lut encapsulated in ethanol-containing and ethanol-free samples both well fitted with the Hixson-Crowell release kinetic model (R2 = 0.92 and 0.94, respectively), and the total phenol content decreased by ≥ 40.02 % and ≥ 62.62 %, respectively. The in vitro antioxidant activity (DPPH, ABTS, and Fe2+) of the digestive products was significantly improved by 23.89 %, 159.69 %, 351.12 % (ethanol groups) and 13.43 %, 125.48 %, 213.95 % (non-ethanol groups). The 3 mg/mL freeze-dried digesta significantly alleviated lipid accumulation and oxidative stress in HepG2 cells. The triglycerides and malondialdehyde contents decreased by at least 57.62 % and 67.74 % after digesta treatment. This study provides an easily approached and environment-friendly strategy to construct a highly loaded protein–flavonoid conjugate, which showed great potential in the formulation of healthier meat products. [ABSTRACT FROM AUTHOR]

The inadvertent flow of mildly/moderately oxidized oil into production critically causes quality uncontrollability in food emulsions. In this paper, we explored the effects of oil pre-oxidation (oxidized before emulsification) on the emulsion stability and interfacial properties of two protein emulsifiers (myofibrillar protein, MP; sodium caseinate, SC). These effects were further found to be different dependent on the proteins native structural and physicochemical properties. For MP with a highly structured fibrous conformation, the adsorption capacity, diffusion and rearrangement rate, and dilatational elastic modulus were decreased (by at least 5.74%, 16.25%, 11.21%, 10.04% respectively) at the oxidized-oil/water interface, which were mainly explained by the increased oil polarity and the generated interfacial-active oxidation products that impeded the interfacial unfolding and protein-protein interactions. With an appreciably high adsorbed amount (adsorption ratio >90%), the MP's oxidized-oil emulsion stability was largely determined by the interfacial properties, and thus significantly decreased with oil oxidation (even at the mild oxidation level). In contrast, for SC with a disordered structure, the rearrangement rate and dilatational elastic modulus were similarly decreased (by at least 14.61%, 12.56% respectively) at the oxidized-oil/water interface, while the adsorption capacity and diffusion rate were increased (by at least 5.40%, 13.16% respectively) possibly due to the enhanced hydrogen bonding between the more hydrophilic SC and the higher polarity oil. With a significantly lower adsorbed amount (adsorption ratio <10%), the SC's oxidized-oil emulsion stability was mainly decided by the oil inherent properties but not interfacial performance, which thus significantly increased with oil oxidation (even at the mild level) due to the growing oil polarity and density. These findings highlight that mild oil pre-oxidation could have critical impacts on emulsion stability, and the mechanism exploration provides scientific guidelines for the quality control and rational formulation of labile unsaturated oil-based emulsion foods (e.g. fat substituted emulsified meat products). [Display omitted] • Oxidation increased oil polarity with the generation of interfacial-active products. • Oil pre-oxidation impaired MP emulsion stability but promoted SC emulsion stability. • Oil pre-oxidation impaired rearrangement rate, interfacial film strength of MP and SC. • Adsorption capacity and diffusion rate varied depended on protein properties. • Dispersed-phase and interfacial-film both mattered in affecting emulsion stability. [ABSTRACT FROM AUTHOR]

The effects of the oils density and viscosity (DV) on the emulsions kinetic stability and destabilization mechanisms were revealed from the perspective of droplets movement and emulsions viscosity. With the extension of storage time, severe creaming (20.20 ± 0.73 × 10−4 mm/s), flocculation and coalescence (7.26 ± 0.82 μm−2 min−1) occurred in emulsions prepared with oils of lowest DV; the extent of creaming (15.90 ± 0.68 × 10−4 mm/s) and coalescence (1.36 ± 0.10 μm−2 min−1) were alleviated upon increasing oils DV, accompanied by the occurrence of acute Ostwald ripening (17.03 ± 1.72 μm3 min−1); and only slight creaming (2.26 ± 0.24 × 10−4 mm/s), flocculation, coalescence (0.70 ± 0.09 μm−2 min−1) and Ostwald ripening (6.14 ± 0.42 μm3 min−1) occurred in emulsions prepared with oils of highest DV. This was because oils with higher DV (especially density) restricted the droplets fluidity due to an increased motion friction, leading to a more homogeneous internal network and a higher apparent/macroscopic viscosity (0.31 ± 0.04 Pa·sn and 0.1 nm−2 s) of emulsions. These impeded the Brownian motion and diffusion of droplets to decrease the collision frequency/efficiency and mass transfer respectively, which in turn conduced to retarding droplets size enlargement and stabilizing the emulsions against different destabilization mechanisms. [Display omitted] • Higher oil density and viscosity (DV) improves emulsions stability. • Oils of high DV increase the emulsion viscosity. • Oils of high DV retard gravitational separation to increase creaming stability. • Oils of high DV delay Brownian motion to increase flocculation/coalescence stability. • Density plays a more decisive role in tuning emulsions viscosity and stability. [ABSTRACT FROM AUTHOR]

In this paper, we study the following quasilinear chemotaxis model with singular sensitivity and indirect signal production (0.1) u t = ∇ ⋅ (D (u) ∇ u) − χ ∇ ⋅ (u v k ∇ v) + u (a − b u) , t > 0 , x ∈ Ω , v t = Δ v − v + w , t > 0 , x ∈ Ω , w t = Δ w − w + u , t > 0 , x ∈ Ω , under homogeneous Neumann boundary conditions in a convex smooth bounded domain Ω ⊂ R N , N ≥ 3 , where, χ , a , b > 0 , k ∈ (0 , 1 2) ∪ (1 2 , 1 ] and D (u) is smooth function satisfying D (u) ≥ (u + 1) α with α > 0. By constructing suitable Lyapunov functional, we prove that if a > χ 2 4 , there exists a positive constant m ∗ such that ∫ Ω u ≥ m ∗. Based on above result, the lower bound estimates for w and v have been established. When b is large enough and α > max { 0 , 1 − 4 N } , we further prove that the system has a global bounded classical solution. Finally, it is shown that the solution exponentially converges to the constant stationary solution (a b , a b , a b) as t → ∞. [ABSTRACT FROM AUTHOR]

Vortex-free high-speed stir casting (VFHSC) methodology can achieve uniform dispersion of particles in melt without air entrapment for fabricating particle reinforced composites, and it has been proved to be feasible for preparing micron-composites by this methodology. In this work, in order to study deeply on particles in nano-size magnitude in composites by this methodology, the preparation of 1.5 vol.% Nano-Al2O3p/Al–Cu–Mg–Si composite is also investigated. The proper stirring parameters for ideal particle dispersion are determined to prepare the materials. Porosity of the composite can be limited to 0.147 % under the VFHSC methodology. The composition and microstructure of ingots, including the incorporation of Al2O3 particles as well as the morphology of precipitated phases, are examined by OM, XRD, SEM, TEM, HRTEM and EDS. The nano-particles are incorporated ideally in the matrix with restricted aggregation and sedimentation, and the well-bounded Al2O3–Al interface possesses semi-coherent interface. Moreover, the VFHSC 1.5 vol.% Nano-Al2O3p/Al–Cu–Mg–Si composite exhibits obvious strengthening, limited ductility reduction, higher hardness as well as better wear resistance than those of matrix, validating the efficacy of the VFHSC methodology on fabricating 1.5 vol.% Nano-Al2O3p/Al–Cu–Mg–Si composite. The work proves that incorporating nano-particles in Al matrix by VFHSC methodology is feasible and efficient. The work presented in this paper proposes a viable approach for the fabrication of nanocomposites using the stir casting method, thereby offering valuable insights for further research on stir casting technology. [ABSTRACT FROM AUTHOR]

This research studies the wave-ship interaction and green water induced by rogue waves. Superposition model is used for rogue wave generation, while a KVLCC2 model is selected as the target ship. Ship motions and impact pressures are obtained numerically, which agree well with the experimental measurements conducted at the State Key Laboratory of Ocean Engineering of China. It is found that the rogue wave can result in severe ship motion responses and impact loadings. The pitch angles and impact pressures at the bow induced by the rogue wave are 2–3 times greater than the average of the background wave train. Two types of green water events are observed, namely the Hammer-Fist (HF) event and the plus dam-breaking (PDB) event, the former of which leads to 3–4 times greater impact pressures than the latter. Additionally, interactions between rogue waves and the ship are further investigated within the ship speed range of 0–20 knots and the encounter angle range of 0–75°. The relationship between encounter frequency and impact pressures on the ship bow, side, stern, and deck induced by rogue waves is quantitatively analyzed, which has reference value as a benchmark for the consideration of rogue wave loadings. • Interactions between rogue waves and a KVLCC2 are studied experimentally and numerically. • Green water events induced by rogue waves are obtained and analyzed in three-dimensional. • Ship motions and impact pressures are obtained to provide a benchmark for the rogue wave and ship interaction. • Influence of encounter frequencies on green water events caused by rogue waves is discussed. [ABSTRACT FROM AUTHOR]

Along the development of ionic porous organic polymers, simple and efficient synthetic methods are actively pursued. Herein, the Debus–Radziszewski reaction is applied to synthesize ionic conjugated microporous polymers (iCMPs) in one step. A series of imidazolium‐linked iCMP‐X (X = 1, 2, 3) are developed for CO2 sorption and in situ conversion with epoxide into cyclic carbonates. The as‐synthesized iCMPs are characterized in detail by scanning electron microscope, solid‐state nuclear magnetic resonance, X‐ray photoelectron spectroscopy, X‐ray diffraction analysis, N2/CO2 sorption, and more. Among all synthesized iCMPs, iCMP‐1 possesses the highest specific surface area and in turn the strongest CO2 sorption capacity. Moreover, through a simple anion ion exchange reaction with halide, iCMP‐1 is transformed to iCMP‐1@Cl that embodies significant catalytic capability for converting CO2 into cyclic carbonates. [ABSTRACT FROM AUTHOR]

This paper introduces a beam‐scanning holographic antenna composed of a substrate‐integrated waveguide (SIW) feeding structure and a rectangular microstrip array. The antenna innovatively combines holographic theory with liquid crystal electrical tunability to realize single‐frequency large‐angle beam scanning function which can effectively solve the problem of beamforming reconfiguration in traditional array antenna systems. In this paper, the variation of dielectric constant of liquid crystal under different bias voltages is quantitatively analyzed. Additionally, the beam forming technology is analyzed under hologram amplitude weighting theory. The relevant theories are verified by manufacturing and testing. The prototype antenna achieves the ultra‐wide beam scanning angle of −63° to 63° at 36 GHz. [ABSTRACT FROM AUTHOR]

Moenomycin A, an antimicrobial growth promoter widely used as an additive in aquaculture feedstuffs, has been restricted for use in the European Union and China due to its potential risk of promoting resistant strains of pathogenic bacteria and causing residues in aquatic animal products. Although methods for analyzing moenomycin A in feedstuffs have been developed, no established method exists for aquatic matrices. In this study, we present, for the first time, a sensitive and validated high-performance liquid chromatography-tandem mass spectrometry (HPLC–MS/MS) method for the determination of moenomycin A in aquatic animal products. Samples were extracted using methanol and purified with the QuEChERS method employing C18 sorbent. The aliquot was dried under a nitrogen stream, reconstituted with methanol-water solvent, and analyzed by HPLC–MS/MS. The developed method exhibited good linearity (r2 > 0.995) over a wide concentration range (1–100 μg/L) and a low limit of detection (1 µg/kg). Average recoveries ranged between 70 and 110% at spiked concentrations of 1, 50, and 100 μg/kg, with associated intra- and inter-day relative standard deviations of 1.25 to 7.32% (n = 6) and 2.91 to 10.08% (n = 3), for different representative aquatic animal production, respectively. To the best of our knowledge, this is the first reported HPLC–MS/MS method for the quantification of moenomycin A in aquatic animal products. The new approach was effectively employed in the analysis of moenomycin A across various aquatic samples. [ABSTRACT FROM AUTHOR]

• ● The ceramsite was successfully produced using MSWI fly ash and granite sawing mud. • ● The raw material ratio and sintering condition of ceramsite was optimized. • ● Chlorine in MG ceramsite mainly enters into the tail gas and secondary fly ash. • ● Chlorine salts are the main chlorine speciation after sintering. Municipal solid waste incineration (MSWI) fly ash is a hazardous waste containing high chlorine and harmful substances generated during the waste incineration disposal, and its resource utilization has a positive effect on reducing environmental pollution. In this study, the feasibility of preparing lightweight MSWI fly ash/granite sawing mud ceramsite (MG ceramsite) was investigated by evaluating the influence of Al 2 O 3 addition, MSWI fly ash content and sintering temperature on the ceramsite properties. The microstructure of MG ceramsite was investigated by using SEM, the chlorine morphological transformation and migration behaviors were simultaneously explored by using the tube furnace experiment, XRD and XRF analyses. The experimental results show that the maximum MSWI fly ash content is about 30 wt%∼35 wt%, with the Al 2 O 3 addition of at least 10 %. By controlling the MSWI fly ash content of 30 wt%, MG ceramsite can be obtained with bulk density of 986 kg/m3, cylindrical compressive strength of 19.67 MPa, 1 h water absorption of 0.31 %, and chlorine content of 0 after sintering at 1150 °C for 20 min. Chlorine in MG ceramsite enters into the tail gas or secondary fly ash in the form of chlorine salts and chlorine-containing gas when the sintering temperature is above 800 °C. The MG ceramsite prepared from MSWI fly ash meets the lightweight aggregate standard and are environmentally friendly. However, the disposal of tail gas and secondary fly ash needs attention when the MSWI fly ash is used as one of the main raw materials to prepare ceramsite. [ABSTRACT FROM AUTHOR]

Exploring advanced chemical sensing applications using porous materials is of critical importance for emerging industries such as Internet of Things, carbon neutrality, new energy resources, etc. Conjugated microporous polymers (CMPs), being well-renowned for their extended π-π conjugations, tunable pore structures, tailored chemical components, and high surface areas, have attracted increasing interests for chemical sensing applications. Here, recent milestones in the sensing applications of CMPs are presented, with an emphasis on the synthetic routes, structural requirements or parameters that dominate their sensing properties and functionalities. This review focuses on multiple chemical sensing devices including: i) fluorescent sensors, ii) electrochemical sensors, iii) colorimetric sensors, iv) resistive sensors, and v) versatile sensors. The key application areas of these CMPs-based sensors for detecting multiple matters including industrial exhausts, explosives, metal cations, halogen species, micropollutants, organic hazards, biological matters, and multiple. species, etc. , are highlighted. The in-depth understanding of the sensing mechanisms and structure-property-function relationships of CMPs are also provided. Finally, a perspective on the future research directions and challenges of CMPs-based sensors is presented. Illustration of the structure-property-function relationships of CMPs and their advanced sensing applications [Display omitted] [ABSTRACT FROM AUTHOR]