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Heterogeneous metallic structures constitute a novel class of materials with excellent mechanical properties. However, the existing process for obtaining heterostructures from a single material does not meet large-scale industrial requirements. In this study, a pure copper heterostructured laminate (HSL) composed of a surface elongated-grain layer and a central equiaxed-grain layer was fabricated by rolling bonding and annealing. To study the effect of the interface on the mechanical properties of gradient-structured materials, both laminate metal composite (LMC) and non-composite laminate (NCL) were fabricated by cold-rolling pretreatment of the center layer (60% reduction) and cold-rolling bonding of the whole blank (67% reduction). Then, the HSL was obtained by controlling the post-annealing regimes, the microstructure of each layer was optimized, and a larger degree of microstructural heterogeneities, such as grain size, misorientation angle, and grain orientation, was obtained, which resulted in obvious mechanical differences. Tensile tests of the HSL, surface layer, center layer, and NCL specimens revealed that the HSL annealed at 300 °C for 1 h had a significantly higher strength than the center layer and a higher elongation than the surface layer. The HSL had a tensile strength and elongation at fracture of 278.08 MPa and 46.2%, respectively, indicating a good balance of strength and plasticity. The improved properties were primarily attributed to the strengthening or strain hardening due to the inhomogeneous deformation of the heterogeneous layers in the laminate and the mutual constraint acquired by the distinct layers with strong mechanical differences. The HSL had an interfacial bonding strength of 178.5 MPa, which played a vital role in the coordinated deformation of the heterogeneous layers. This study proposes an HSL design method that effectively simplifies the process of obtaining heterostructures in homogeneous materials by controlling the cumulative deformation of the surface and center layers. [ABSTRACT FROM AUTHOR]

The interface is the weakest region of the coal-backfilling composite structure (CBCS) for underground mines, the sawtooth angles of which is one of the most critical concerns to be accounted. However, limited studies have focused on the deformation and failure behaviours of CBCS with different interface sawtooth angles under double shearing. To investigate the effect of interface sawtooth angles on the damage characteristics of CBCS under double shearing, CBCS with different interface sawtooth angles (i.e., 0°, 15°, 30°, 45°, 60°) were prepared and double shearing tests were carried out in the present research. Macroscopic failure characteristics (i.e., failure mode, failure process, and shear strength) of the CBCS were experimentally investigated via the digital image correlation (DIC), acoustic emission (AE), and 3D scanner system, whereas microscopic feature of which, including the contact force–microcrack evolution, and displacement vector of CBCS were numerical simulated by the discrete element modelling (DEM) method. The results showed that the failure modes of the CBCS can be classified into three types (e.g., climbing failure, cutting failure, and sliding failure). Among them, the climbing failure was only occurred when the loads on the sawtooth surfaces exceeded its shear strength, while the cutting failure occurred if the load on the sawtooth end of the coal element or backfilling element exceeded its shear strength. The sliding failure occurred, because the load applied to the interface exceeded the shear strength of the specimen interface. Moreover, the peak shear stress, the degree of strain concentration, and the extent of the strain concentration zone of the CBCS increased with the enlarged sawtooth angle. The research outcomes will contribute to obtain an in-depth understanding about the mechanical response of the coal-backfill composites under double shear loading. Highlights: Double shearing tests were carried out on coal-backfilling composite structures and the shear behaviour of CBCS was observed by DIC and AE monitoring systems. The contact force–microcrack distribution and displacement vector of CBCS during double shearing were investigated using DEM. Deformation and failure characteristics of CBCS were revealed from a microscopic and macroscopic perspective. The mechanisms of the double shearing failure process of CBCS with different interface sawtooth angles were revealed. [ABSTRACT FROM AUTHOR]

Highlights: A new strategy for elaborate regulation of microstructure was successfully introduced by the ice template‑assisted 3D printing and chemical vapor deposition strategy, including graphene nanoplate/silicon carbide nanowires hierarchical porous structure and graphene nanoplate/boron nitride composite heterogeneous interface. The composite exhibits excellent electromagnetic wave absorption performance with an RLmin of -37.8 dB and an EABmax of 9.2 GHz (from 8.8 to 18.0 GHz) at 2.5 mm. And the high-temperature absorption stability makes it a promising absorber candidate under high temperature and oxidizing atmosphere. With vigorous developments in nanotechnology, the elaborate regulation of microstructure shows attractive potential in the design of electromagnetic wave absorbers. Herein, a hierarchical porous structure and composite heterogeneous interface are constructed successfully to optimize the electromagnetic loss capacity. The macro–micro-synergistic graphene aerogel formed by the ice template‑assisted 3D printing strategy is cut by silicon carbide nanowires (SiCnws) grown in situ, while boron nitride (BN) interfacial structure is introduced on graphene nanoplates. The unique composite structure forces multiple scattering of incident EMWs, ensuring the combined effects of interfacial polarization, conduction networks, and magnetic-dielectric synergy. Therefore, the as-prepared composites present a minimum reflection loss value of − 37.8 dB and a wide effective absorption bandwidth (EAB) of 9.2 GHz (from 8.8 to 18.0 GHz) at 2.5 mm. Besides, relying on the intrinsic high-temperature resistance of SiCnws and BN, the EAB also remains above 5.0 GHz after annealing in air environment at 600 °C for 10 h. [ABSTRACT FROM AUTHOR]

Maintaining eye contact is a fundamental aspect of non-verbal communication, yet current remote communication tools, such as video calls, struggle to replicate the natural eye contact experienced in face-to-face interactions. This study presents a cutting-edge vision-sharing system for android avatars that enables remote eye contact by synchronizing the eye movements of the operator and the avatar. Our innovative system features an eyeball integrated with a wide-angle lens camera, meticulously designed to mimic human eyes in both appearance and functionality. This technology is seamlessly integrated into android avatars, enabling operators to perceive the avatar's surroundings as if physically present. It provides a stable and immersive visual experience through a head-mounted display synchronized with the avatar's gaze direction. Through rigorous experimental evaluations, we demonstrated the system's ability to faithfully replicate the operator's perspective through the avatar, making eye contact more intuitive and effortless compared with conventional methods. Subjective assessments further validated the system's capacity to reduce operational workload and enhance user experience. These compelling findings underscore the potential of our vision-sharing system to elevate the realism and efficacy of remote communication using android avatars. [ABSTRACT FROM AUTHOR]

Ultralow temperature crystals of the helium isotopes 3 He and 4 He are intriguing quantum systems. Deciphering the complex features of these unusual materials has been made possible in large part by Alexander Andreev's groundbreaking research. In 1978, Andreev and Alexander Parshin predicted the existence of melting/freezing waves at the surface of a solid 4 He crystal, which was subsequently promptly detected. Successively, for the fermionic 3 He superfluid/solid interface, even more intricate crystallization waves were anticipated, although they have not been observed experimentally so far. In this work, we provide preliminary results on 3 He crystals at the temperature T = 0.41 mK, supporting the existence of spin supercurrents in the melting/freezing waves on the crystal surface below the antiferromagnetic ordering temperature T N = 0.93 mK, as predicted by Andreev. The spin currents that accompany such a melting-freezing wave make it a unique object, in which the inertial mass is distinctly different from the gravitational mass. [ABSTRACT FROM AUTHOR]

The motivation for this paper is the analysis of the fixed-density Ising lattice gas in the presence of a gravitational field. This is seen as a particular instance of an Ising model with a slowly varying magnetic field in the fixed magnetization ensemble. We first characterize the typical magnetization profiles in the regime in which the contribution of the magnetic field competes with the bulk energy term. We then discuss in more detail the particular case of a gravitational field and the arising interfacial phenomena. In particular, we identify the macroscopic profile and propose several conjectures concerning the interface appearing in the phase coexistence regime. The latter are supported by explicit computations in an effective model. Finally, we state some conjectures concerning equilibrium crystal shapes in the presence of a gravitational field, when the latter contributes to the energy only to surface order. [ABSTRACT FROM AUTHOR]

Polymer dielectric materials possess advantages of high breakdown strength, low dielectric loss and easily to processing, etc., thus attract wide attention and play a crucial role in modern electronic industry and advanced energy storage applications. However, at high temperature, the energy storage density and efficiency of polymer dielectric decrease significantly and cannot meet practical application requirements. Crosslinking strategy is considered as one of the most feasible methods for polymer dielectric to meet high temperature requirements. This article mainly reviews the research progress in recent years on the preparation of PVDF dielectric polymers with crosslinking structure using physical crosslinking methods (hydrogen bonding crosslinking), chemical crosslinking methods (photo-crosslinking, thermal crosslinking, self-crosslinking), and physical–chemical dual crosslinking methods. The different principles and process methods for obtaining PVDF dielectric polymers with crosslinking structure were summarized, and the dielectric properties of crosslinked and uncrosslinked PVDF polymers were compared. It was found that PVDF dielectric polymers with a crosslinking structure have good energy storage density and charge–discharge efficiency, and have excellent dielectric properties at high temperatures. This provides a strategy and process method for exploring high-performance polymer dielectric materials suitable for new electronic devices under high-temperature conditions. [ABSTRACT FROM AUTHOR]

In this work, the AZ31/1060 laminated metal composites with Zn interlayer were successfully prepared by hot pressing with a strain of 47% in the atmospheric environment at 350 °C. The effects of the hot-pressing rate (from 3.3 × 10−4 to 1.0 × 10−2 s−1) on the interfacial structure and shear strength were examined. The quality of interface bonding and phase compositions at the interface are significantly affected by hot-pressing rate. With the decrease in strain rate, voids and cracks at the interfaces can be eliminated, and the phase compositions of the Mg/Al interface were changed from the Al-Zn solid solution, Zn and MgZn2 to Mg-Zn-Al ternary compounds. The hot-pressing time plays a decisive role in the compositions of diffusion zone. The maximum shear strength can be obtained in the sample hot-pressed at a strain rate of 1.0 × 10−3 s−1 due to that fracture occurred mainly in the MgZn2 layer. When the ternary Mg-Zn-Al phase exists at the interface, the bonding strength will be largely deteriorated. [ABSTRACT FROM AUTHOR]

High-quality antiferromagnetic Mott insulator thin films of LaTiO3 (LTO) were epitaxially grown onto SrTiO3 (STO) (110) substrates using the pulsed laser deposition. The LTO/STO heterostructures are not only highly conducting and ferromagnetic, but also show Kondo effect, Shubnikov-de Haas (SdH) oscillations with a nonzero Berry phase of π, and low-field hysteretic negative magnetoresistance (MR). Angle-dependent SdH oscillations and a calculation of the thickness of the interfacial conducting layer indicate the formation of a 4-nm high mobility two-dimensional electron gas (2DEG) layer at the interface. Moreover, an amazingly large low-field negative MR of ∼61.8% is observed at 1.8 K and 200 Oe, which is approximately one to two orders of magnitude larger than those observed in other spin-polarized 2DEG oxide systems. All these results demonstrate that the 2DEG is spin-polarized and the 4-nm interfacial layer is ferromagnetic, which are attributed to the presence of magnetic Ti3+ ions due to interfacial oxygen vacancies and the diffusion of La3+ ions into the STO substrate. The localized Ti3+ magnetic moments couple to high mobility itinerant electrons under magnetic fields, giving rise to the observed low-field MR. Our work demonstrates the great potential of antiferromagnetic titanate oxide interface for designing spin-polarized 2DEG and spintronic devices. [ABSTRACT FROM AUTHOR]

Highlights: The constructions under internal and external driving forces were introduced and compared with each other. The physicochemical properties were analyzed for the assessment of crystalline quality and photoelectric characteristics. The photocatalytic applications, mechanisms, and developments of the core-shell semiconductor-graphene nanoarchitectures were illustrated in detail. Semiconductor photocatalysis holds great promise for renewable energy generation and environment remediation, but generally suffers from the serious drawbacks on light absorption, charge generation and transport, and structural stability that limit the performance. The core–shell semiconductor-graphene (CSSG) nanoarchitectures may address these issues due to their unique structures with exceptional physical and chemical properties. This review explores recent advances of the CSSG nanoarchitectures in the photocatalytic performance. It starts with the classification of the CSSG nanoarchitectures by the dimensionality. Then, the construction methods under internal and external driving forces were introduced and compared with each other. Afterward, the physicochemical properties and photocatalytic applications of these nanoarchitectures were discussed, with a focus on their role in photocatalysis. It ends with a summary and some perspectives on future development of the CSSG nanoarchitectures toward highly efficient photocatalysts with extensive application. By harnessing the synergistic capabilities of the CSSG architectures, we aim to address pressing environmental and energy challenges and drive scientific progress in these fields. [ABSTRACT FROM AUTHOR]

To enhance the Young's modulus (E) and strength of titanium alloys, we designed titanium matrix composites with interconnected microstructure based on the Hashin-Shtrikman theory. According to the results, the in-situ reaction yielded an interconnected microstructure composed of Ti2C particles when the Ti2C content reached 50vol%. With widths of 10 and 230 nm, the intraparticle Ti lamellae in the prepared composite exhibited a bimodal size distribution due to precipitation and the unreacted Ti phase within the grown Ti2C particles. The composites with interconnected microstructure attained superior properties, including E of 174.3 GPa and ultimate flexural strength of 1014 GPa. Compared with that of pure Ti, the E of the composite was increased by 55% due to the high Ti2C content and interconnected microstructure. The outstanding strength resulted from the strong interfacial bonding, load-bearing capacity of interconnected Ti2C particles, and bimodal intraparticle Ti lamellae, which minimized the average crack driving force. Interrupted flexural tests revealed preferential crack initiation along the {001} cleavage plane and grain boundary of Ti2C in the region with the highest tensile stress. In addition, the propagation can be efficiently inhibited by interparticle Ti grains, which prevented the brittle fracture of the composites. [ABSTRACT FROM AUTHOR]

We have investigated the basic mechanism of carbon nanotube (CNT) interactions with various room-temperature ionic liquids (RTILs) using molecular dynamics (MD) simulations. To understand the effects of the cation molecular geometry on the properties of the interface structure in the RTIL systems, we have studied a set of three RTILs with the same [BF4]- (tetrafluoroborate) anion but with different cations, namely, [EMIM]+ (1-ethyl-3-methylimidazolium), [BMIM]+ (1-butyl-3-methylimidazolium), [HMIM]+ (1-hexyl-3-methylimidazolium), and [OMIM]+ (1-octyl-3-methylimidazolium) ions. The simulation results showed that the imidazolium cations exhibit two distinct orientations (perpendicular and parallel to the CNTs surface) at the interface irrespective of the alkyl chain length of the cations. The average number of hydrogen bonds per cations inside the CNT was found to be higher for [OMIM][BF4] (1.01), which suggests that [OMIM]+ imidazolium rings to be concentrated at the center of the CNT, which favors hydrogen bond. The reported results show the diffusion coefficients of ions in confinement are much lower in comparison to the bulk region. The interaction energy between [OMIM][BF4] (-8.75 kcal.mol−1.ion−1) and CNT was found to be higher as compared to other ILs. The cations paralleling the CNT surface are thermodynamically significantly more stable because of the substantial interfacial π-π stacking interactions, as shown by a comparison with the calculated interaction energies between cations and the CNTs. Our simulation results provide a molecular-level understanding of the stabilization and dispersion of CNT bundles in ILs. [ABSTRACT FROM AUTHOR]

The van der Waals interface structures and behaviors are of great importance in determining the physical properties of two-dimensional atomic crystals and their heterostructures. The delicate interfacial properties are sensitively dependent on the mechanical behaviors of atomically thin films under external strain. Here, we investigated the strain-engineered rippling structures at the CVD-grown bilayer-MoS2 interface with advanced atomic force microscopy (AFM). The in-plane compressive strain is sequentially introduced into the 1L-substrate and 2L-1L interface of bilayer-MoS2 flakes via a fast-cooling process. The thermal strain-engineered rippling structures were directly visualized at the central 2H- and 3R-MoS2 bilayer regions with friction force microscopy (FFM) and bimodal AFM techniques. These rippling structures can be further artificially manipulated into the beating-like rippling features and fully erased via the contact mode AFM scanning. Our results shed lights on the strain-engineered interfacial structures of two-dimensional materials and also inspire the further investigation on the interface engineering of their electronic and optical properties. [ABSTRACT FROM AUTHOR]

Although mangrove forests are great carbon sinks, they also release carbon dioxide (CO2) from soil, plants, and water through respiration. Many studies have focused on CO2 effluxes only from soils, but the role of biogenic structures such as pneumatophore roots has been poorly studied. Hence, CO2 effluxes from pneumatophores were quantified at sediment-air (non-flooded sediment) and water–air (flooded sediment) interfaces along a salinity gradient in three mangrove types (fringe, scrub, and basin) dominated by Avicennia germinans during the dry and rainy seasons in Yucatan, Mexico. Pneumatophore abundance explained up to 91% of CO2 effluxes for scrub, 87% for fringe, and 83% for basin mangrove forests at the water–air interface. Overall, CO2 effluxes were inversely correlated with temperature and salinity. The highest CO2 effluxes were in the fringe and the lowest were in the scrub mangrove forests. Flooding decreased CO2 effluxes from the dry to the rainy season in all mangrove forests. These results highlight the contribution of pneumatophores to mangrove respiration, and the need to include them in our current carbon budgets and models, but considering different exchange interfaces, seasons, and mangrove ecotypes. [ABSTRACT FROM AUTHOR]

Interface microstructures of metallic coatings at end faces are critical for durability of metallic polypropylene (MPP) capacitors. However, the microstructures are difficult to be regulated efficiently due to the specificity of the polymer substrates. Therefore, ZnAl coatings were deposited at end faces of MPP capacitors by arc spraying. The temperature and velocity of in-flight droplets were regulated with different spray distance. A modified numerical simulation with a combustion model was employed to calculate the temperature and velocity of the droplets. The interface microstructures and equivalent series resistance of the capacitors were characterized. The results show that the temperature of the droplets continued to increase during the flight due to exothermic oxidation. The interface of the coatings with the spray distance of 150 mm presented a dendritic microstructure with deeper embedment depth and more bonding layers. The bonding layers reduced as the spray distance decreased to 120 mm because of the damage of the MPP layers. The embedment depth of the coatings decreased as the spray distance increased to 180 mm due to lower temperature of the droplets. The equivalent series resistance of the capacitors decreased to 7.84 mΩ with the dendritic interface microstructures. The research provides a new numerical model to optimize arc spraying and improve the quality of MPP capacitors. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) stacking using hybrid bonding is the most scalable method for 3D integration. As the hybrid bonding pad width is reduced to adopt a higher number of interconnections, the ability to extract the contact resistivity at the bonding interface with high accuracy is critical. Using specific electrical test structures and a dedicated methodology, we extract the contact resistivity for hybrid bonding pad widths down to 400 nm for a Cu/SiO2 hybrid bonding integration. Very low values around 10−11 Ω cm2 were obtained for our reference process, close to the those of Cu grain boundaries. A comprehensive analysis of the experimental contact resistivity is performed to understand its increase with the Cu recess within the bonding pads. Based on thermomechanical simulations and experimental results, the influence of both the pad thickness and initial dishing on the interface closure is discussed, for bonding pad width down to 100 nm. These analyses enable us to propose process conditions to reach low contact resistivity with low sensitivity to wafer-to-wafer overlay for hybrid bonding stacking using bonding pad widths down to 100 nm. [ABSTRACT FROM AUTHOR]

The progress of stretchable organic light-emitting devices (OLEDs) has brought about new possibilities for highly functional wearable electronics. However, the efficiency and durability of stretchable OLEDs have been limited by the performance of stretchable transparent electrodes. Here, we proposed an interface engineering strategy that involves anchoring the growth of silver (Ag) atoms with amine-enriched biomaterials for high-quality stretchable transparent electrodes. The strong interactions between the Ag atom and the amine group enable the uniform Ag electrodes at an ultralow thickness of 7 nm, and provide remarkable mechanical flexibility and strain endurance to the Ag electrodes. The distinct effects of different amino acids were investigated, and a deep understanding of their unique contributions to the film formation process was gained. The resulting ultrathin Ag electrodes exhibit outstanding optoelectrical properties (transmittance of ~ 98% and sheet resistance of ~ 8.7 Ω/sq) and excellent stretchability during 500 stretching cycles at 100% strain. Stretchable green phosphorescent OLEDs based on the Ag electrodes have been demonstrated with a current efficiency of up to ~ 70.4 cd/A. Impressively, the devices show excellent stretching stability, retaining ~ 89% of the original luminance and ~ 78% of the original current efficiency after 200 stretching cycles at 100% strain. This work opens up new possibilities for stretchable transparent electrodes, fostering advancements in wearable displays and other innovative flexible devices. [ABSTRACT FROM AUTHOR]

This study analysed the failure of dissimilar metal welds (DMWs) between ferritic heat resistant steels and austenitic stainless steels and investigated its influencing factors by means of numerical simulation, microstructure characterization and mechanical property test. Under the long-term high-temperature service condition in practical power plant, the DMW failure mode was along the interface between nickel-based weld metal (WM) and ferritic heat resistant steel, and the failure mechanism was stress/strain concentration, microstructure degradation and oxidation coupling acting on the interface. The numerical simulation results show that interface stress/strain concentration was due to the differences in coefficient of thermal expansion and creep strength, and the degree of stress/strain concentration was related to service time. The ferrite band formed at the WM/ferritic steel interface was prone to cracking, attracting the fracture along the interface. The interface crack allowed oxidation to develop along the WM/ferritic steel interface. During long-term service, the interface stress/strain concentration, microstructure and oxidation all evolved, which synergistically promoted interface failure of DMW. However, only under the long-term service of low stress conditions could trigger the interface failure of DMW. Meanwhile, long-term service would reduce the mechanical strength and plasticity of DMW. [ABSTRACT FROM AUTHOR]

We perform a quantitative analysis of the concentration of an impurity migrating with a solution in a three-layer porous body in the presence of sorption processes on the contact boundaries of macroelements under the conditions of imperfect mass contact. To determine the desired functions from the contact conditions of equality of the diffusion fluxes, we deduce a system of integral equations. On the basis of the numerical analysis of the obtained solutions, it is shown that the variations of the sorption intensity factors in the second and third contacting layers, of the relative diffusion coefficient in the second layer, of the convective transfer velocity coefficients in the first and second layers, and of the coefficients of concentration dependence of chemical potentials strongly affect the behavior and/or the values of the impurity concentration functions on the contact boundaries of the macroelements participating in the formation of the porous layer. [ABSTRACT FROM AUTHOR]

The effect of high-temperature annealing pretreatment above Accm on the evolution of bainitic austempering microstructure in Fe – 0.95C – 1.37Si – 1.04Cr – 0.44Mn (wt.%) steel is investigated by differential thermal analysis, x-ray diffraction and high-resolution transmission electron microscopy. It is found that a novel nanobainite with a needle-like morphology forms in the experimental steel under conventional bainitic austempering after annealing pretreatment at 950°C. A thin film crystal of the novel nanobainite with a thickness as small as 50 nm has a body-centered cubic lattice, in which the opposite stacking fault is the main crystal defect. The interface of the novel nanobainite crystal is composed of both coherent and non-coherent areas. The steel containing the novel nanobainite structure has a higher hardness than that with conventional bainite. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs), especially inorganic NPs, have been used as fillers to improve the insulation properties of polymers. However, inorganic NPs is difficult to disperse well in polymer matrix, which inhibit the development of insulating nanocomposites for high-voltage direct current power cable. Therefore, it is necessary to improve the dispersion of NPs in the polymer matrix in order to make NPs play a greater role. In this work, polystyrene NPs (PS-NPs) were synthesized and used as fillers to improve the insulation properties of LLDPE. SEM images show that PS-NPs are monodispersed in LLDPE matrix without thermal fusion when the content of PS-NPs is less than 1 wt%. The results of DSC illustrate that the addition of PS-NPs had no effected on thermal behavior of LLDPE. With the introduction of PS-NPs, the DC breakdown strength of LLDPE/PS-NPs is first increased and then decreased. The highest value of 346.5 kV/mm is obtained by PS-0.1 with 0.1 wt% of PS-NPs. The electric conductivity of all LLDPE/PS-NPs composites are decreased comparing with neat LLDPE. Meanwhile, PS-NPs had no significant influence on the dielectric permittivity and dielectric loss of the complex. Therefore, PS-NPs is an alternative option to improve the insulating performance, and our results provide a way for the development of nanocomposites insulating material. [ABSTRACT FROM AUTHOR]

6061 aluminum alloy and 304 stainless steel were joined successfully by thermo-compensated resistance diffusion welding (abbreviated as TC-RDW) technology with Ni interlayer via pre-resistance seam welding (abbreviated as RSW). Experimental results indicated the metallurgical bond between interlayer and steel based on pre-RSW achieved a large-area Al/Ni/steel joint with better interfacial structure by subsequent TC-RBW process. An obvious diffusion layer with the main components of Al solid solution (s.s) was formed between Al alloy and interlayer in the final Al/steel joints. The interfacial structure was changed as follows: Al alloy, diffusion layer, interlayer, and steel. The tensile-shear load of the final Al/Ni/steel welded joint by this method reached 1793.3N, which was more than 3 times higher than that of the Al/steel joint via TC-RBW directly. The specimens mainly fractured at the interface between Al alloy and Ni interlayer after tensile-shear experiments. XRD analysis results confirmed that Al (s.s), Fe (s.s), and Ni (s.s) were generated at the fracture surface. [ABSTRACT FROM AUTHOR]

The mutual effects and the structure of interface in blends of low-density polyethylene (PE) and polycaprolactone (PCL) with different ratios of components (differing by 10 wt %) were studied. The creation of blended composites of this kind based on one polymer capable of photodegradation under the action of ultraviolet radiation and another polymer prone to hydrolytic degradation under the action of microbiota makes it possible to obtain materials with an enhanced ability to undergo fast abiotic and biotic degradation after use. Blended films with high PCL contents (over 80 wt %) showed mutual compatibility of polymers, forming a developed interfacial layer, which imparts increased tensile strength and hardness to the film. The phase inversion ranges were determined to be 10–30 wt % PCL (continuous PE phase with a discontinuous PCL phase), 40–60 wt % PCL (net-in-net structure) and 70–90 wt % (continuous PCL phase with a discontinuous PE phase). The composite containing 70 wt % PCL was characterized by the greatest defectiveness of internal structure, and the composite with 90 wt % PCL had the most optimum set of both mechanical and technological properties. [ABSTRACT FROM AUTHOR]

The study was carried out by LEED, AES, EELS, and AFM methods. Films of Fe/Si(001)2 × 1 were obtained at substrate temperatures of 30°C and source temperatures of 1250°C. Wetting layer (WL) Fe on Si(001)2 × 1 was formed by two-stage annealing at temperatures and thicknesses of 500 and 250°C and 1 monolayer (ML) and 3 ML, respectively. Analysis and interpretation of the data obtained, taking into account possible reaction patterns, showed that after annealing at 1 ML thickness, the Fe composition corresponded to 2 ML Si/Fe. Further, at 2 ML, it changed to Fe/Si/Fe, at 3 ML, it changed to Fe–FeSi, and after annealing, to FeSi. At 4 ML, there was formation of FeSi/FeSi2 film. And, further, at 7 ML and 10 ML, the composition of the films became Fe3Si/FeSi2 and, respectively, Fe/Fe3Si/FeSi2. At the same time, the upper Fe3Si layers were coated with 0.6 ML and the Fe layers with 0.3 ML of segregated Si atoms, which number increased, after annealing at 250°C, to 0.6 ML in the latter case. In the obtained Fe film, the size and average grain height were 10−20 nm and, respectively, ∼0.4 nm. [ABSTRACT FROM AUTHOR]

This study improves and expands the scope of application of the theoretical model previously proposed by the authors, which describes the relationship between the strength and electromigration (diffusion) properties of interfaces formed by connected materials. In the developed model, a linear relationship is established between the values of the work of reversible interface separation and electromigration activation energy in the interface. Estimates are made and the coefficients of the resulting relation are compared with experiments studying electromigration in a copper conductor coated with a protective dielectric. Using also the model previously developed by the authors, which describes the dependence of the quantity on the concentrations of nonequilibrium lattice defects presenting in the volumes of connected materials, a number of effects due to the influence of such defects on processes caused by electromigration are predicted and studied. This study shows that by introducing nonequilibrium lattice defects in the form of atomic interstitial or substitutional impurities into the volumes of the joined materials, we can effectively influence on the characteristics of the electromigration instability of the shape of the interlayer boundary. For interstitial impurities, quantitative analytical estimates of the impurity concentration required to significantly change (both increase and decrease) the characteristic growth time of the instability of the shape of an initially flat interface are performed. [ABSTRACT FROM AUTHOR]

The growth of germanium nanoparticles' thin films on rough SiO 2 surfaces through the sputtering technique was analyzed based on thermodynamic principles. The study proposes a predictive model that allows controlling the size, distribution, and crystalline quality of nanoparticles embedded in oxides by adjusting the corresponding growth parameters in reactive sputtering. Surfaces based on two-dimensional Brownian motion, a precise modeling technique, were used to model the rough surface. A mathematical relation between the Hurst exponent and root mean square of a surface measured is used to reconstruct theoretical roughness surfaces. The modeling predictions were compared with statistical results obtained through atomic force microscopy measurements. Additionally, we find that the interfacial thin film-surface energy impacts the crystallization process. [ABSTRACT FROM AUTHOR]

Hybrids of carbon nanotube and metals have been regarded as promising candidate for flexible circuit, where thermal stability of nanograined metals is a challenging issue. In this study, we find thermal stability of Cu layer in CNT–Cu hybrids can be improved by coating Al2O3 layer. As for CNT–Cu hybrids, Cu nanograins are agglomerated during 673 K annealing. In contrast, the agglomeration of CNT–Cu hybrids can be suppressed after coating Al2O3 layer, and exhibit a thickness-dependent thermal stability after annealing at higher temperature. The underlying mechanism might be the compressive stress applied by Al2O3 coatings and inhibited diffusion along Cu/Al2O3 interfaces. [ABSTRACT FROM AUTHOR]

Pulse investigations of resistive switching in planar memristive heterocontacts based on Nd2 – xC-exCuO4 – y epitaxial films are presented. The possibility of regulating metastable resistive states in planar memristive systems based on such films is studied using specific protocols of pulse measurements. Various metastable states are implemented by changing external parameters: the frequency and magnitude of the electric-field voltage applied to the heterocontacts. Dynamic effects are investigated, and the transition times between metastable states are determined. Direct investigation involves alteration of the electrodynamic properties under the effect of a sinusoidal alternating electric field at frequencies of 10–3 Hz and in the pulsed mode with pulse durations ranging from 0.1 ms to 25 s. This is accomplished by measuring the current–voltage characteristics, recording the current and voltage oscillograms at the heterocontact, and examining the temperature-dependent resistivity of metastable phases. The multilevel nature of the metastable resistive states in the studied systems and the ability to control switching times characterize the adaptability of these devices and their potential use as memory elements for neuromorphic applications in spiking neural networks. [ABSTRACT FROM AUTHOR]

The values of the fiber-matrix adhesive strength are presented, as well as electron microscopic data on the microstructure of the polymer matrix and interfacial layer for fiberglass in the initial state and after exposure to various climatic factors. The most significant drop in adhesive strength was observed for the sample after heat and humidity aging and subsequent thermal cycling. [ABSTRACT FROM AUTHOR]

Li-CO2 batteries are among the most intriguing techniques for balancing the carbon cycle, but are challenged by the annoyed thermodynamic barrier of the Li2CO3 decomposition reaction. Herein, we demonstrate the electrocatalytic performances of two-dimensional (2D) CoAl-layer double hydroxide (LDH) nanosheets can be significantly improved by trans-dimensional crosslinking with three-dimensional (3D) multilevel nanoporous (MP)-RuCoAl alloy (MP-RuCoAl alloy ⊥ CoAl-LDH). The MP-RuCoAl alloy⊥CoAl-LDH with multiscale pore channels and abundant nano-heterointerface is directly prepared by controllable etching Al from a Ru-Co-Al master alloy along with simultaneous partial oxidization of Al and Co atoms. The MP-RuCoAl is composed of various intermetallic compounds and Ru with abundant grain boundaries, and forms numerous heterointerface with 2D CoAl-LDH nanosheets. The multiscale porous metallic network benefits mass and electron transportation as well as discharge product storage and enables a rich multiphase reaction interface. In situ differential electrochemical mass spectrometry shows that the mass-to-charge ratio in the charging process is ∼ 0.733 which is consistent with the theoretical value of 3/4, stating that the reversible co-decomposition of Li2CO3 and C can be achieved with the MP-RuCoAl alloy⊥CoAl-LDH. The Ketjen black (KB)/MP-RuCoAl⊥CoAl-LDH battery demonstrates a high cyclability for over 2270 h (227 cycles) with a lower voltage gap stabilized at ∼ 1.3 V at 200 mA·g−1. Our findings here provide useful guidelines for developing high efficiency transition metal based electrocatalysts by coupling with conductive porous substrate for impelling the development of practical Li-CO2 battery systems. [ABSTRACT FROM AUTHOR]

Due to the rapid advancement of technologies, there has been a significant increase in the discharge of industrial wastewater, and freshwater is becoming a scarce resource. Currently, research on solar evaporators is mainly focused on the efficient production of clean water, with less emphasis on the removal of residual pollutants remaining in the original solutions. Through this study, problems, including the difficult recovery of catalyst powder and the difficult removal of floating organic matter are solved by co-depositing low-surface-tension zirconia particles and bismuth tungstate onto the floating layer. Hydrogels and melamine sponges were combined to solve the problem that traditional hydrogels lack mechanical strength. An excellent water-repellent effect can be seen from the contact angle between the liquid globule and canvas/felt, which is greater than 155°. The steam generation rate of the assembled evaporation system is 1.78 kg m−2 h−1, and its purification efficiency for methyl orange and rhodamine B exceeds 99%. This study presents a novel strategy for treating wastewater contaminated with organic dyes, aiming to solve problems including environmental damage, water pollution, and water scarcity. [ABSTRACT FROM AUTHOR]

Copyright of Die Pathologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The association between two types of concrete at different stages is common in precast connections, composite beams, and repairs, creating an interface. High-Strength Concrete (HSC) is extensively used in precast industries. Ultra-High-Performance Concrete (UHPC) is suitable for filling the HSC-UHPC connection due to its exceptional mechanical properties and adhesion capability. This study investigated the normal and tangential stiffness of the HSC-UHPC interface using different surface preparations: Exposed coarse aggregates, Shear keys, Exposed fine aggregate, Expanded mesh, Exposed fiber and Smooth (no special treatment). The stiffness of the interface was assessed through four-point bending, splitting tension and push-off tests. The normal stiffness coefficient derived from the four-point bending test proved more suitable than the stiffness coefficient obtained from the splitting tensile test. A trend between roughness and normal stiffness was observed, indicating decreased normal stiffness as roughness increased. Although the roughness of the interface influenced the normal stiffness by affecting adhesion and mechanical interlocking, its impact on tangential stiffness was not clearly observed and depended on the interface treatment. The normal and tangential stiffness parameters obtained at the HSC-UHPC interface were significantly higher than those observed in previous studies on the Normal Strength Concrete-UHPC interface. The complete nonlinear load displacement curves were provided to represent the interface behavior between HSC-UHPC considering different types of tests and surface preparations. A range of normal and tangential stiffness parameters was obtained, which can be useful in future research aiming to modeling the interface between HSC and UHPC. [ABSTRACT FROM AUTHOR]

Tunability of interfacial effects between two-dimensional (2D) crystals is crucial not only for understanding the intrinsic properties of each system, but also for designing electronic devices based on ultra-thin heterostructures. A prerequisite of such heterostructure engineering is the availability of 2D crystals with different degrees of interfacial interactions. In this work, we report a controlled epitaxial growth of monolayer TaSe2 with different structural phases, 1H and 1 T, on a bilayer graphene (BLG) substrate using molecular beam epitaxy, and its impact on the electronic properties of the heterostructures using angle-resolved photoemission spectroscopy. 1H-TaSe2 exhibits significant charge transfer and band hybridization at the interface, whereas 1 T-TaSe2 shows weak interactions with the substrate. The distinct interfacial interactions are attributed to the dual effects from the differences of the work functions as well as the relative interlayer distance between TaSe2 films and BLG substrate. The method demonstrated here provides a viable route towards interface engineering in a variety of transition-metal dichalcogenides that can be applied to future nano-devices with designed electronic properties. [ABSTRACT FROM AUTHOR]

Pure Ti (Grade 1) and Ni (type Ni201) were used to produce the Ti/Ni welds employing the explosive welding process. Thermal expansion of the welded plates was determined using dilatometric measurements from room temperature up to 600 °C. The results showed that the thermal expansion coefficient of Ti/Ni welded plates is closer to that of pure nickel than would be suggested by the Timoshenko’s model for bimetallic strip. The microstructure of the Ti/Ni interface after exposure to high temperatures revealed the presence of extensive interface porosity (Kirkendall porosity). This may cause a catastrophic disintegration of the weld during working or essential forming. The welded plates were annealed at the temperature of 650 °C under different applied compressive loads, and the applied load was shown to alter the microstructure of the NixTiy phases present at the Ti/Ni interface. Based on the obtained interface microstructural data, the strategy to suppress the Kirkendall porosity at the interface was proposed. [ABSTRACT FROM AUTHOR]

Bimetal materials are composed of dissimilar metals, which are increasingly used to fabricate components that withstand harsh thermal and mechanical environments. In this work, aluminum-brass bimetallic hollow cylinders were produced using the vertical centrifugal casting process, and their interface was studied. Aluminum melt, with two different liquid-to-solid volume ratios of 1.5 and 2.5, was cast into brass hollow cylinders preheated to 100–400°C and rotated at 800, 1600, and 2000 rotation-per-minute. The sector-shaped samples were then studied using X-ray diffraction analysis, optical microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. It was found that the interface consisted of three discernible layers. These included the chill zone (Al2Cu5Zn4 + Al3Cu3Zn) near the brass side, platelet precipitate zone (Al2Cu precipitates scattered in α-Al solid solution matrix), and finally anomalous (or divorced) eutectic grains (α-Al/Al3Cu) near the aluminum side. Mechanical tests were carried out, in particular Brinell, Vickers and compression tests. The findings revealed that the adhesion of the interface was reduced by increasing the thickness of the interface. Fractography of fractured surfaces illustrated the presence of flat faces (Al2Cu precipitates) locked together and deep depressions associated with cup-shaped dimples (α-Al/Al3Cu eutectic). [ABSTRACT FROM AUTHOR]

Linear low-density polyethylene (LLDPE) is a type of plastic with a high percentage of solid waste and is hardly degradable. The characteristics of LLDPE such as high toughness and low density have the potential to be an alternative aggregate substitute for applications in non-structural mortar composites. The purpose of this study was to determine the suitable formulation of LLDPE aggregate substitution against silica sand for the application of non-structural adhesive mortar composites. Vinyl acetate/ethylene (VAE) surfactant (1.2 wt%) was used to improve the interface between LLDPE and the cement matrix. Mechanical testing; XRD and FTIR characterization; density measurements; compression, adhesion, and thermogravimetric test; and morphological observation were carried out in this experiment. The results showed that LLDPE substitution decreased physical properties and accelerated thermal degradation. Cracks occurred on higher amount of LLDPE composition due to big difference in polarity. Suitable LLDPE substitution composition for adhesive mortar is up to 50%. [ABSTRACT FROM AUTHOR]

The shear bond of interface between concrete and basalt fiber reinforced polymer (BFRP) bars during freeze-thaw (F-T) cycles is crucial for the application of BFRP bar-reinforced concrete structures in cold regions. In this study, 48 groups of pull-out specimens were designed to test the shear bond of the BFRP-concrete interface subjected to F-T cycles. The effects of concrete strength, diameter, and embedment length of BFRP rebar were investigated under numerous F-T cycles. Test results showed that a larger diameter or longer embedment length of BFRP rebar resulted in lower interfacial shear bond behavior, such as interfacial bond strength, initial stiffness, and energy absorption, after the interface goes through F-T cycles. However, higher concrete strength and fewer F-T cycles were beneficial for enhancing the interfacial bond behavior. Subsequently, a three-dimensional (3D) interfacial model based on the finite element method was developed, and the interfacial bond behavior of the specimens was analyzed in-depth. Finally, a degradation bond strength subjected to F-T cycles was predicted by a proposed mechanical model. The predictions were fully consistent with the tested results. The model demonstrated accuracy in describing the shear bond behavior of the interface under numerous F-T cycles. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Doping rare earth elements in WC-Co cemented carbide can make the additives and the original elements form a complex structure, thus further strengthening the overall structure and improving the comprehensive properties of cemented carbide. In this paper, the rare earth element La is added to the cemented carbide WC-Co. Through the construction of atomic cell and interface, the influence of La element on WC-Co cemented carbides is analyzed. The influence law of La atom on other atoms is explained according to analyze the adhesion work, reaction enthalpy, electronic state density and charge density. The results show that more covalent bonds are generated near lanthanum atoms at the interface junction, which enhances the interface bonding strength, makes the whole structure more stable, and the unit cell doped with La element has better stability and improves the overall toughness. The calculation results can provide data for enhancing the performance of cemented carbides and provide a theoretical basis for doping rare earth lanthanum in WC-Co cemented carbides in the future. [ABSTRACT FROM AUTHOR]

The poor EMI shielding ability, limited UV resistance, and weak interfacial adhesion have restricted the use of Ultra-high molecular weight polyethylene (UHMWPE) fabric in ballistic, aviation, and other applications. To overcome these drawbacks, the present study proposes an electroless composite coating (NiP/MWCNT) on UHMWPE fabric surface with different weight propositions of MWCNTs (1 mg/L, 2 mg/L, and 3 mg/L). Comparative analysis in terms of morphology, surface roughness, functional groups, UV absorption, phase structure, surface energy, flammability, tensile load, peeling load, and EMI shielding was carried out to understand the influence of MWCNTs concentration in the NiP/MWCNT composite coating. Morphological analysis revealed that when the concentration of MWCNT increases, the nodular structure changes and the coating structure turns coarser. In addition, UV absorption, surface roughness, and crystal size increased and the burning rate during the flammability test decreased. Fabric tensile test and peel test results revealed improvements in breaking load and peeling load with higher MWCNTs concentration. In the X band frequency range, NiP/MWCNT composite coating exhibited higher shielding effectiveness (SET = 64.10 dB) for a lower coating thickness of 0.033 mm compared to NiP coating (SET = 42.25 dB) with a higher coating thickness of 0.038 mm. This article further details the EMI shielding, surface energy, single yarn tensile test, and the peeling load of NiP/MWCNT composite-coated UHMWPE fabrics. [ABSTRACT FROM AUTHOR]

Abstract—The chemical state of MoSx catalytic layers and interfaces with p-type silicon (p-Si) and p–n-junction silicon (pn-Si) at various stages of preparation and operation of photocathodes is studied. The SiOx oxide layer formed at the interface noticeably suppresses the photocurrent for p-Si cathodes, but its removal in the HF solution provides high photocurrents exceeding the values characteristic of pn-Si cathodes at zero potential. Studies of the energy bands show that, at all stages (after the formation of the photocathode, pre- and post-processing in acid solutions), the configuration of the energy bands for p-Si and pn-Si photocathodes provides charge transfer for the evolution of hydrogen according to the Z-scheme. The difference in the characteristics of p-Si and pn-Si photocathodes is due to the possible dependence of the photovoltage in the surface layer of p-Si on the state of the interface with the catalyst film, which does not affect the photovoltage in pn-Si. [ABSTRACT FROM AUTHOR]

Polymer dielectrics with a high energy density and an available energy storage capacity have been playing an important role in advanced electronics and power systems. Nevertheless, the use of polymer dielectrics in harsh environments is limited by their low energy density at high temperatures. Herein, zirconium dioxide (ZrO2) nanoparticles were decorated with amino group utilizing 4,4-methylenebis (phenyl isocyanate) (AMEO) and successfully incorporated into polyetherimide (PEI) matrix. The dielectric properties, breakdown strength, and energy storage performances of PEI/ZrO2-AMEO nanocomposites were investigated from 25 °C to 150 °C. It is found that the combination of moderate bandgap ZrO2 with modest dielectric constant and polar groups at interface with deep trap can offer an available strategy to simultaneously increase the dielectric constant and breakdown strength of polymer dielectrics. As a result, the composites containing ZrO2-AMEO exhibit excellent energy storage performance at elevated temperatures. Specially, the PEI-based composites with 3 vol% ZrO2-AMEO display a maximum discharged energy density (Ud) of 3.1 J/cm3 at 150 °C, presenting 90% higher than that of neat PEI. This study may help to better develop the polymer-based dielectric composite applied at elevated temperatures. [ABSTRACT FROM AUTHOR]

The proposed model describes the behavior of the lubricant particles at the interface between two surfaces for a group of cylindrical semi-solid lubricant fragments observed in a real beetle leg joint. It is shown that the lubricant particles may maintain a gap between joint surfaces at load. At the regular shear motion, such randomly oriented particles are reorienting perpendicular to the shear and function as a rolling bearing: the system demonstrates the lowest energy loss and lowest friction. At an increased load, the friction non-linearly increases, because of an increase of the particles' eccentricity. Finally, at some load, the particle rotation stops, friction switches from the rolling to the sliding regime and increases significantly. [ABSTRACT FROM AUTHOR]

The chemical and phase composition of oxide layers on U8, U10, and 45 tool steel samples formed by laser treatment is studied by X-ray photoelectron spectroscopy. In the surface layers of the samples, the depth of the oxide layers (Fe2O3, Fe3O4, FeO) is the same, but their thickness is different. That affects the tribological properties. [ABSTRACT FROM AUTHOR]

For dissimilar metal welds (DMWs) involving nickel-based weld metal (WM) and ferritic heat resistant steel base metal (BM) in power plants, there must be an interface between WM and BM, and this interface suffers mechanical and microstructure mismatches and is often the rupture location of premature failure. In this study, a new form of WM/BM interface form, namely double Y-type interface was designed for the DMWs. Creep behaviors and life of DMWs containing double Y-type interface and conventional I-type interface were compared by finite element analysis and creep tests, and creep failure mechanisms were investigated by stress-strain analysis and microstructure characterization. By applying double Y-type interface instead of conventional I-type interface, failure location of DMW could be shifted from the WM/ferritic heat-affected zone (HAZ) interface into the ferritic HAZ or even the ferritic BM, and the failure mode change improved the creep life of DMW. The interface premature failure of I-type interface DMW was related to the coupling effect of microstructure degradation, stress and strain concentrations, and oxide notch on the WM/HAZ interface. The creep failure of double Y-type interface DMW was the result of Type IV fracture due to the creep voids and micro-cracks on fine-grain boundaries in HAZ, which was a result of the matrix softening of HAZ and lack of precipitate pinning at fine-grain boundaries. The double Y-type interface form separated the stress and strain concentrations in DMW from the WM/HAZ interface, preventing the trigger effect of oxide notch on interface failure and inhibiting the interfacial microstructure cracking. It is a novel scheme to prolong creep life and enhance reliability of DMW, by means of optimizing the interface form, decoupling the damage factors from WM/HAZ interface, and then changing the failure mechanism and shifting the failure location. [ABSTRACT FROM AUTHOR]

Enhancing the tunneling magneto-Seebeck (TMS) ratio and uncovering its underlying mechanism are greatly demanded in spin caloritronics. The magnitude and sign of the TMS effect depend on the type of atom and the stacking order of atoms at the interfaces. Herein, we demonstrate that TMS ratios can be effectively manipulated by altering heterogonous or homogeneous interface through decoration on the CoFeSi (001) surface inserted on the MgO insulating layers. The maximum TMS ratio of pure Co2/O termination is 4565% at 800 K. Notably, the TMS ratio of the FeSi/O termination has two peak values, of which the maximum could reach up to −3290% at 650 K. By comparing two different atom arrangements at the interface, we reveal that the sign and symbol of the TMS ratio can be controlled by the temperature and different atomic configurations at the Co2FeSi/MgO interface. Furthermore, the spin-Seebeck coefficient up to ∼150 µV/K is also possible when we select suitable terminations and temperatures. These findings will provide useful insights into how to control the sign and symbol of the TMS ratio and accordingly stimulate the development field of magneto-thermoelectric power and spin caloritronic devices based on the magneto-Seebeck effect in Heusler-based metallic multilayers. [ABSTRACT FROM AUTHOR]

In this paper, we propose a space-time finite element method for a time fractional diffusion interface problem. This method uses the low-order discontinuous Galerkin (DG) method and the Nitsche extended finite element method (Nitsche-XFEM) for temporal and spatial discretization, respectively. Sharp pointwise-in-time error estimates in graded temporal grids are derived, without any smoothness assumptions on the solution. Finally, three numerical examples are provided to verify the theoretical results. [ABSTRACT FROM AUTHOR]

The layered metal oxides are reviewed as the hopeful cathode materials for high-performance sodium-ion batteries (SIBs) due to their large theoretical capacity, favorable two-dimensional (2D) ion diffusion channel, and simple manipuility. However, their cycling stability, rate capability, and thermal stability are still significantly concerned and highlighted before further practical application. The chemical, mechanical and electrochemical stability of the cathode–electrolyte interfaces upon cycling is of great significance. Herein, the unique structural and electrochemical properties of the layered oxide cathode materials for SIB are reviewed. The mechanism of bulk/surface degradation induced by oxygen evolution, phase transition, microcrack, and electrolyte decomposition is thoroughly understood. Furthermore, the interfacial engineering to construct stable interface through various effective methods is fully discussed. The future outlook and challenges for interfacial engineering in this filed are also summarized. This review should shed light on the rational design and construct of robust interface for applications of superior layered oxide cathodes in SIB and may suggest future research directions. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the influence of adhesive resin application modalities on the film thickness of the adhesive resin and the effectiveness of a two-step universal adhesive (UA) bonded in self-etch (SE) bonding mode to high C-factor class-I cavity-bottom dentin. Materials and methods: After application of the primer of G2-Bond Universal (G2B, GC), the adhesive resin was applied into standard class-I cavities (human molars) following four application modalities: (1) one layer, strongly air-blown; (2) one layer, gently air-blown; (3) two layers, each gently air-blown; (4) one layer, not air-blown. After being restored with composite, each tooth was sectioned to obtain one micro-specimen (n = 10), of which the adhesive resin film thickness was measured using optical microscopy. The micro-tensile bond strength (μTBS) was tested immediately or upon 100,000 thermocycles. Statistical analyses involved Kruskal–Wallis and Mann–Whitney U testing (p < 0.05). Results: G2B’s μTBS was significantly affected by the adhesive resin application modality and aging. Gently air-blowing the adhesive resin resulted in significantly higher immediate μTBS than strong air-blowing or no air-blowing. No significant difference in μTBS was found between single or double gently air-blown adhesive resin applications. The adhesive resin film thickness significantly varied with the application modalities. Conclusions: A too thin or too thick adhesive resin film thickness adversely affected bond strength of the two-step UA applied in SE mode and high C-factor condition. Clinical relevance: The adhesive resin layer thickness can affect the bonding performance of two-step UAs in high C-factor cavities. Dental clinicians remain advised to avoid improper air-blowing of UAs and strictly follow the application instructions. [ABSTRACT FROM AUTHOR]