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Grafting polyphenols and glycosylation are effective means to enhance the wettability and emulsifying properties of natural protein particles. A stable pickering emulsion (PE) with antioxidant properties was prepared using β-Lactoglobulin-Rosmarinic acid-Pectin (β-LG-RA-PC) conjugates as stabilizers in this study. When PC and β-LG-RA with the same mass were covalently combined, the solid protein-based particles exhibited ideal wettability (84.2 ± 0.3°), emulsification performance, and molecular flexibility. PEs with an oil content of 66.7% were successfully prepared using a 10 mg/mL concentration of the complex. The intrinsic reasons for the stabilization of the PE were explored through interfacial tension (from 16.02 mN/m to 12.18 mN/m), adsorption kinetics, interfacial expansion viscoelastic modulus (the tangent of the phase angle was 0.22), microstructure, and rheological properties, revealing that the dense, ideally viscoelastic interface layer formed was the main factor. The electrostatic repulsion between droplets, and the formation of a robust spatial network structure, facilitated PEs' stability. These studies confirmed the possibility of implementing protein-based particles to yield food-grade PE. [Display omitted] • The grafting rate for the same mass of β-Lactoglobulin-Rosmarinic acid (β-LG-RA) conjugate and pectin (PC) reached 39.07%. • Pickering emulsions (PEs) prepared with β-LG-RA-PC (8–12 mg/mL) exhibited a solid-like structure. • The viscoelastic interface and accumulated network structure increased the stability of PEs. • The addition of RA and PC could make the three-phase contact angle of β-LG-RA-PC nanoparticles close to 90°. [ABSTRACT FROM AUTHOR]

For the AgCuOIn 2 O 3 SnO 2 electrical contact composites, the interfacial bonding state and microstructure of each oxide with the silver matrix are still unknown, and in order to elucidate the interfacial state between Ag and CuO, first-principles calculations based on density-functional theory are used to establish the low-exponential surfaces of Ag and CuO, respectively, and to perform convergence tests. The computational results show that the Ag (111) surface and the CuO(100)-CuO surface are the most stable surfaces among the respective low-exponential surfaces, and thus the Ag (111) surface and the CuO(100)-CuO surface are selected to constitute the interfacial model, and the atomic structure, the adhesion work, and the interfacial energies of the interfaces are systematically analyzed. The calculation results show that the Ag (111)/CuO(100)-CuO interface has metallic properties and still has strong electrical conductivity, when the interface spacing d 0 = 3.0 Å, the interfacial adsorption work is the largest, and the value of the interfacial energy is the lowest and positive, which indicates that the Ag (111)/CuO(100)-CuO interface exists stably thermodynamically, and the interfacial stability is relatively good. Moreover, the Ag/CuO interface is bonded by ionic bonding and partial covalent bonding, the interface is well bonded, and the O atoms play a more critical role in the interfacial bonding, and the accuracy of the calculated results is verified by experiments. [Display omitted] • The Ag (111) surface and the CuO(100)-CuO surface are the most stable of the respective low-index surfaces. • The interfacial energy, electronic properties, microstructure of the Ag (111)/CuO(100)-CuO interface were investigated. • The Ag/CuO interface is bonded by ionic and partially covalent bonds, with O atoms playing a more critical role. • The veracity of the model predictions was confirmed by the orientation analysis of Ag and CuO. • Declaration of competing interest [ABSTRACT FROM AUTHOR]

The cross wedge rolling (CWR) method was used to produce laminated shafts of chromium-molybdenum steel (42CrMo). The effect of the rolling temperature on interface properties of composite 42CrMo/Q235 laminated shaft were explored, for example, the interface micro-structure, chromium diffusion, micro-hardness, bonding strength, and tensile fracture morphology. Results indicate that after rolling, the core material (Q235) and the clad material (42CrMo) combined effectively and formed a notable interface. Under high tem-perature rolling and composite binding, the chromium dif-fused near the interface. By rising the rolling temperature, the diffusion depth of chromium from the clad material to the core material increased. Near the interface of 42CrMo/Q235, the micro-hardness changes gradient. By rising the rolling temperature, the micro-hardness of same location decreased. The maximum interface bonding strength is 1100 °C, the maximum tensile strength is 532.0 MPa, and the maxi-mum shear strength is 422.3 MPa. Scanning electron microscope (SEM) images display the tensile fracture with a typical ductile dimple fracture pattern. Raising the rolling tempera-ture, the size of the dimple increased and the oxide at the bottom of the dimple decreased. At a rolling temperature of 1100 °C, the interface bonding strength should be the highest, which correlated with the interface bonding strength test results. [ABSTRACT FROM AUTHOR]

Dissimilar welding of austenitic stainless steel (ASS) to low-alloy structural steel is widely used in the power generation industry. The formation of brittle martensite and hot cracking susceptibility in the single-phase austenite microstructure are the main concerns related to the metallurgy of this kind of weld. This study investigates the effect of different welding wires and the weaving technique on the quality, microstructure and microhardness of fillet weld joints between AISI 304L austenitic stainless steel and S355MC low-alloy structural steel. Using robotised synergic gas metal arc welding (GMAW), three different filler wires were used to weld specimens with and without weaving. The macro-sections of the fillet welds were inspected and the dilution rates and ferrite numbers (FN) measured. The microstructure was also inspected and microhardness values recorded. Porosity was discerned in two weld samples made with the use of weave beads. The measured FNs for all the weldments were very close to estimations from the Schaeffler diagram. The formation of a narrow martensitic band on the ferritic side of the weld metal was detected for most of the specimens. It is concluded that weaving decreased the dilution rate and increased the FN. However, no obvious effect on the microstructure and hardness as a result of using the weaving technique was noticed. [ABSTRACT FROM AUTHOR]

Highly particle-filled polymer composites (HPFPCs) usually consist of stiff crystal particles, polymeric binder/matrix and the interfaces between the particles and the matrix. Unlike normal particle-filled composites, the particle filled ratio of HPFPCs can reach around 90% to 95% by weight, which makes it difficult to study the mechanical properties of HPFPCs by traditional schemes. To explore the mechanical performance of HPFPCs thoroughly, the influences of strain rate, temperature, interface properties (interface strength and fracture energy), and micro-structure (particle volume fraction (PVF) and particle distribution) on the fracture mechanisms have been systematically investigated using the nonlinear finite element method. A micro numerical scheme has been developed, including the development of mechanical constitutive models for each constituent of HPFPCs, and the generation of the micro-structural model with the PVF of over 90% using a Voronoi-modified method. The multiple failure events have been reproduced including the visco-elastic deformation, the fracture of the matrix, and interfacial debonding dominating the crack mode. The predicted results are in good agreement with the available experimental measurements and other numerical simulation results. This work provides a robust numerical tool to analyse the micro-mechanical behaviour of HPFPCs. [ABSTRACT FROM AUTHOR]

Abstract: The investigation on the interface properties of fcc-CoPt/CoO thin films grown by Pulsed Laser Deposition is presented. The structural and microstructural properties of the CoO antiferromagnetic layer have been modulated by thermal treatments in order to investigate their influence on the magnetic behavior of the system. [Copyright &y& Elsevier]

• This paper analyzes the microstructure and electrical insulation characteristics at the interface of 500 kV XLPE cable factory joints for EHVDC application. • Microporous defects are observed at the interface and the #1000 roughness is the threshold beyond which the trend of each parameter is reversed. • Degassing treatment promotes the orderly folding and recrystallization of the molecular chains arranged the amorphous region and significantly reduces the microporous defects at the interface. • An interfacial microscopic model and a charge transfer model are proposed to analyze the mechanism of material properties under different roughnesses and electric fields. This paper analyzes the microstructure and electrical insulation characteristics at the interface of 500 kV cross-linked polyethylene (XLPE) cable factory joints for extra high voltage direct current (EHVDC) application. The interface between two layers was polished by different grit sandpapers (80, 400, 1000, 2000, and 0000 (unpolished)). The samples (#1000) polished by 1000 grit mesh at the interface were degassed at 70°C for 0, 12, 36, 90, and 200 h, respectively. Physico-chemical and electrical experiments were performed on the prepared test samples. It is found that increasing the number of sandpaper grit meshes reduces the average lamellae thickness at the interface and increases the crystallinity. Moreover, microporous defects are observed at the interface. The parameters viz elongation at break, current density, and the number of microporous defects increase initially and then decrease. However, the space charge accumulation, threshold electric field strength, and DC breakdown decrease initially and then increase. Notably, the #1000 roughness is a turning point. On the other side, degassing treatment promotes the orderly folding and recrystallization of the molecular chains arranged the amorphous region and significantly reduces the microporous defects at the interface. The mechanical properties are affected to a certain extent. The improved microstructure reduces the space charge accumulation and the current density of the sample, and increases the DC breakdown strength. An interfacial microscopic model and a charge transport model are proposed to analyze the mechanism of material properties under different roughnesses and electric fields. The results indicate that the ultra-smooth interface and degassing treatment strengthen the molecular chain linking at the interface. Moreover, they significantly reduce the microporous defects at the interface and improve the insulation properties of the factory joint. [ABSTRACT FROM AUTHOR]