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Mononuclear ruthenium complex 1and dinuclear complex 2were synthesized by reaction of the appropriate bidentate pyrazolyl-pyridyl-based ligand L (L = 1,4-bis(3-(2-pyridyl)pyrazol-1-ylmethyl)benzene) with cis-Ru(bipy)2Cl2·2H2O. They were characterized by elemental analyses, ESI-MS, 1H spectroscopy, and X-ray crystallography for 2. Compounds 1and 2both emit strongly in solid states and in solutions at 298 K with the lifetimes in the microsecond range. Electrogenerated chemiluminescence (ECL) of complexes 1and 2in the absence or presence of coreactant tri-n-propylamine (TPrA) or 2-(dibutylamino)ethanol (DBAE) at different working electrodes in acetonitrile and phosphate buffer solutions (PBS, pH 7.5) was studied. The ECL spectra are identical to the photoluminescence spectra, indicating that the ECL emissions are due to the metal to ligand charge transfer (MLCT). In all cases, ECL quantum efficiencies of dinuclear complex 2are higher than those of mononuclear complex 1, and ECL quantum efficiencies of complexes 1and 2/TPrA system are higher than those of DBAE system. It is noted that diuretic furosemide tends to decrease the ECL intensity of complex 2/TPrA system in PBS (pH 7.5) at GC working electrode. A novel ECL method for the determination of diuretic furosemide was developed with a linear range between 2.0 × 10−7mol L−1and 1.0 × 10−6mol L−1, and a detection limit of 1.2 × 10−8mol L−1based on 3 times the ratio of signal-to-noise. [ABSTRACT FROM AUTHOR]

Herein, we reported a facile method to fabricate ultra-stable, surfactant- and antimicrobial-free Pickering emulsions by designing and modulating emulsions’ interfaces via zein/chitosan colloid particles (ZCCPs). Highly charged ZCCPs with neutral wettability were produced by a facile anti-solvent procedure. The ZCCPs were shown to be effective Pickering emulsifiers because the emulsions formed were highly resistant to coalescence over a 9-month storage period. The ZCCPs were adsorbed irreversibly at the interface during emulsification, forming a hybrid network framework in which zein particles were embedded within the chitosan network, yielding ultra-stable food-grade zein/chitosan colloid particles stabilized Pickering emulsions (ZCCPEs). Moreover, stable surfactant-free oil gels were obtained by a one-step freeze-drying process of the precursor ZCCPEs. This distinctive interfacial architecture accounted for the favourable physical performance, and potentially oxidative and microbial stability of the emulsions and/or oil gels. This work opens up a promising route via a food-grade Pickering emulsion-template approach to transform liquid oil into solid-like fats with zero trans -fat formation. [ABSTRACT FROM AUTHOR]

High entropy (AlCrNbSiTi)N hard coatings have been deposited by pulsed arc ion plating with various duty cycles. The effects of duty cycles on the morphology, chemical composition, microstructure and mechanical properties of coatings are studied. Higher duty cycles result in the increase of deposited particles and holes on the surface of the coatings. The coatings exhibited a single-phase face centered cubic structure with preferred orientation of (200). Appropriate duty cycle can significantly improve the comprehensive mechanical properties of the coatings. The coating exhibits highest hardness and elastic modulus of 43.4 GPa and 573.4 GPa, respectively. Formation of surface oxides during friction process are observed, which play a self-lubricating role. • The cross sections of all coatings are featureless and dense. • The coatings have typical single-phase B1–NaCl FCC solid solution crystal structure with (200) preferred orientation. • Coating deposited at 60 % duty cycle exhibits highest hardness of 43.4 GPa. [ABSTRACT FROM AUTHOR]

We report for the first time the usage of mono-dispersed gliadin/chitosan hybrid particles as a particulate emulsifier for Pickering high internal phase emulsions (HIPEs) development. The hybrid particles with partial wettability were fabricated at pH 5.0 using a facile anti-solvent route. Stable Pickering HIPEs with internal phases of up to 83% can be prepared with low particle concentrations (0.5–2%). The hybrid latexes were effectively adsorbed and anchored at the oil–water interface to exert steric hindrance against coalescence. Concomitantly, the compressed droplets in Pickering HIPEs to form a percolating 3D-network framework endowed the emulsions viscoelastic and self-standing features. The protective effect of Pickering HIPEs on curcumin was confirmed, and the content of primary oxidation products in HIPEs was slightly lower than that in bulk oil. This work opens an attractive strategy to convert liquid oils to viscoelastic soft solids without artificial trans fats, as a potential alternative for PHOs. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate for the first time the use of gliadin colloid particles (GCPs) as an effective particulate stabilizer of oil-in-water emulsions of natural oils and water. For this purpose, we fabricated GCPs through a facile anti-solvent precipitation procedure and demonstrated their uses in the formation of Pickering emulsions as well as Pickering high internal phase emulsions (HIPEs). We found that unmodified GCPs can produce stable, surfactant-free o/w emulsions with microscale droplet sizes under experimental mixing conditions at pH 4 and above. In contrast, the emulsions were not stable against coalescence at ∼pH 3.0. The microstructures, e.g., interfacial framework, GCPs partition between the continuous phase and interfacial region, and state of the droplets, of Pickering emulsions as a function of pH were visualized by optical microscopy and confocal laser scanning microscopy (CLSM), confirming that in addition to Pickering stabilization, the GCPs-based network and/or dispersed droplets-based network also contributed to the stabilization of the emulsions, in a pH-dependent manner. Clear correlations exist between colloid properties of the GCPs dispersions and the emulsion characteristics. Interestingly, stable surfactant-free Pickering HIPEs were fabricated by a facile shearing emulsification. This study opens a promising route based on Pickering HIPEs to transform liquid oils into viscoelastic emulsion gels with zero trans-fat and less saturated fat. The Pickering HIPEs possess promising potentials to replace solid fat in food formulations, which outline new directions for future fundamental research. [ABSTRACT FROM AUTHOR]

As an important organic semiconductor, copper phthalocyanine has been widely used in various photo/electronic devices. Until now, the one-step synthesis of copper phthalocyanine micro/nano-crystals is mainly limited to the high cost physical vapor deposition technology. Herein, for the first time, we proposed a green and low-cost solvothermal method for direct synthesis of highly crystalline copper phthalocyanine needles in nontoxic anhydrous ethanol medium at 190 °C. The purification of the as prepared copper phthalocyanine needles just required washing unreacted reactants with ethanol. The structures and morphologies of the copper phthalocyanine needles were characterized by Raman spectroscopy, X-ray powder diffractometor, and scanning electronic microscopy, respectively. Moreover, the thermal and photoelectronic performances were investigated preliminarily. [ABSTRACT FROM AUTHOR]

Microstructure heterogeneity of emulsion films impaired their physical performances. This work attempted to fabricate novel high-barrier chitosan (CH) emulsion films by manipulating emulsion's interface architecture via Pickering stabilization approach. Some selected physical properties, including tensile property, water vapor permeability (WVP), and oxygen permeability (OP) as well as the microstructure of the films were evaluated. Film-forming emulsions (FFEs) based on zein/chitosan colloid particles-stabilized Pickering emulsions (ZCCPEs) were extremely stable, evidenced by the similar droplets size and size distribution in the FFEs and film matrix, endowing the films with homogeneous distributions of lipid droplets over their 3D network matrix. Interestingly, emulsion films exhibited excellent oxygen-barrier efficiency, and the OP of the films was decreased by 1−4 orders of magnitude when compared with CH films. This phenomenon may be associated with the novel interfacial architecture of ZCCPEs as well as film microstructure morphology based on ordered assembles of CH matrix and ZCCPEs. A schematic diagram for the formation pathway of ZCCPEs-loaded CH emulsion films was proposed to establish structure-function relationships of the films. This study opens a promising pathway for producing emulsion films with excellent oxygen-barrier capability via Pickering stabilization principle. [ABSTRACT FROM AUTHOR]