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In low-permeability sandstone reservoirs (LPSR), impermeable interlayers significantly challenge carbon capture, utilization, and storage (CCUS) and enhance oil recovery (CO2-EOR) processes by creating complex, discontinuous flow units. This study aims to address these challenges through a comprehensive multi-faceted approach integrating geological and microscopic analyses, including core analysis, reservoir petrography, field emission-scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), and well-logging response analysis, and utilizing three-dimensional (3D) geological modeling. The current comprehensive investigation systematically characterizes interlayer types, petrophysical properties, thickness, connectivity, and their spatial distribution in the reservoir unit. Numerical simulations were conducted to assess the sealing efficiency and the impact of various interlayer materials on CO2 flooding over a 10-year period. Results indicate the presence of petrophysical and argillaceous interlayers, with optimal sealing occurring in petrophysical barriers ≥ 4 m and argillaceous barriers ≥ 1.5 m thick. CO2 leakage occurs through preferential pathways that emerge in a side-to-middle and bottom-to-top direction in interbeds, with multidirectional pathways showing greater leakage at the bottom compared to the upper side within barriers. Increased interlayer thickness constraints CO2 breakthrough but reduces vertical flooding area and production ratio compared to homogeneous reservoirs. Augmented interbed thickness and area mitigate CO2 breakthrough time while constraining gravity override and dispersion effects, enhancing horizontal oil displacement. These novel findings provide crucial insights for optimizing CCUS-EOR strategies in LPSR, offering a robust theoretical foundation for future applications and serving as a key reference for CO2 utilization in challenging geological settings of LPSR worldwide. [ABSTRACT FROM AUTHOR]

Memristors are promising candidates for next-generation non-volatile memory devices, offering low power consumption and high-speed switching capabilities. However, conventional metal oxide-based memristors are constrained by fabrication complexity and high costs, limiting their commercial viability. Organic–inorganic hybrid perovskites (OIHPs), known for their facile solution processability and unique ionic–electronic conductivity, provide an attractive alternative. This study presents a conjugated polyelectrolyte (CPE), PhNa-1T, as an interlayer for OIHP memristors to enhance the high-resistance state (HRS) performance. A post-treatment process using n-octylammonium bromide (OABr) was further applied to optimize the interlayer properties. Devices treated with PhNa-1T/OABr achieved a significantly improved ON/OFF ratio of 2150, compared to 197 for untreated devices. Systematic characterization revealed that OABr treatment improved film morphology, reduced crystallite strain, and optimized energy level alignment, thereby reinforcing the Schottky barrier and minimizing current leakage. These findings highlight the potential of tailored interlayer engineering to improve OIHP-based memristor performance, offering promising prospects for applications in non-volatile memory technologies. [ABSTRACT FROM AUTHOR]

In this study, the interfacial cracking mechanism of Cr-coated Zircaloy cladding tubes was investigated through a combination of tensile testing, advanced microstructural characterization, and first-principle calculations. The results demonstrate the presence of an interlayer (33 nm) between the Cr coating and the Zr substrate, which consists of Cr and O elements. In comparison with the coherent Cr/interlayer interface, the incoherent interlayer/Zr interface is conducive to crack initiation and propagation, resulting from local high strain concentration generated by incompatible deformation between the interlayer and Zr substrate, and O-induced reductions in Cr/Zr interfacial cohesive strength. [ABSTRACT FROM AUTHOR]

The distribution of interlayers in reservoirs has a significant impact on the flow of reservoir fluids. Accurate identification of interlayer distribution is crucial for analyzing oil–water migration patterns and formulating optimal development strategies. Current research on interlayers mainly focuses on qualitative analysis, particularly regarding sedimentary environments and petrophysical characteristics. However, research on the quantitative analysis of interlayers is relatively scarce, and most identification methods rely on manual interpretation, which introduces human bias. To address this issue, this paper proposes an automatic interlayer identification method based on logging curve units, in P Oilfield. By analyzing the sedimentary and petrophysical characteristics of argillaceous and calcareous interlayers, along with their logging curve responses, multiple logging curves are integrated into a single comprehensive curve. This enables the automatic identification of both single-well and inter-well interlayers, achieving an identification accuracy of up to 90%. This method effectively improves the accuracy and efficiency of interlayer identification and demonstrates high application potential. Analyzing actual data from the P Oilfield, this study reveals the dominant role of interlayers in controlling the distribution of remaining oil in bottom-water reservoirs. It also summarizes three typical remaining oil distribution patterns: basal oil, dome oil, and cap oil. These findings provide practical guidance for subsequent oilfield development and enhanced recovery. This method not only offers an automated solution for interlayer identification in oilfields but also provides scientific evidence for precise decision-making in oilfield development. [ABSTRACT FROM AUTHOR]

Purpose: The non-uniform sedimentary structure of tailings storage facilities (TSFs) has significant adverse effects on dam seepage and stability. However, the spatial distribution of tailings is disordered and the resulting sedimentary structures of TSFs have not been thoroughly understood. The objective is to investigate the complex sedimentary structures of tailings under different discharge conditions. Methods: A flume with a length of 20 m and a width of 2 m was built, and a series of flume tests with different discharge parameters were conducted. The depositional characteristics and formation mechanism were statistically investigated in terms of particle size distribution in the horizontal and vertical directions, the micro fabric of sediment, and the interlayer structure. Results: The hydraulic sorting is obvious. In the transitional region between the channel zone and laminar flow zone, d50 and d10 both undergo a sudden decrease. Vertically, the mean particle size of sediment is linearly related to the depth of each profile. The fabric pattern of sedimentary particle orientation changes from a spindle shape to a circular shape with increasing slurry concentration or decreasing discharge flow rate, indicating that particle deposition is clearly anisotropic and directional. Three new types of interlayers were observed: silt or clay interlayers in sand layers, sandy lenticles interbedded in muddy sediment and bedding structure interlayers. Conclusions: This study represents the first effort to analyse the micro fabric characteristics of tailings sediment and the formation mechanism of interlayer structure. This quantitative study provides useful information for the modelling and safety evaluation of TSFs. [ABSTRACT FROM AUTHOR]

The Hudson Oilfield's Donghe sandstone reservoir has multiple independent oil–water systems. The complex oil–water relationship is mainly due to reservoir heterogeneity, especially the sealing and shielding effects of interlayers. This paper uses methods like well logging and test well data interpretation, seismic impedance inversion, and the simulation of oil and gas preferential migration paths. It analyzes and quantifies parameters related to sand layer oil content, physical properties, and the development degree of interbedded layers using small layers as units. Sandstone horizontal transportability has three types. Type I matches structural forms to form preferential migration paths. Type II transportability has enclosed sand bodies that obstruct oil and gas flow and change their migration paths. Unevenly distributed calcareous interbedded layers are the main controlling factor for vertical sand body transportability. Locally continuous cemented calcareous interbedded layers can form the base of a dome-shaped pinch-out lithologic trap in sandstone. The closure area of the trap is controlled by the pinch-out line of sandstone and the distribution of continuous interbedded layers together. [ABSTRACT FROM AUTHOR]

Lithium metal solid‐state batteries (LMSSBs) are considered to be one of the ultimate choices for future energy storage systems because of their high theoretical energy density and enhanced safety. However, the development of LMSSBs has been seriously hindered by some practical issues, such as Li dendrite penetration in the solid‐state electrolytes (SSEs) and uncontrolled interphase growth at the Li/SSE interface, which can cause severe battery degradation, failure, and even safety hazards. To construct safe high‐performance LMSSBs, it is crucial to gain an in‐depth understanding of the failure mechanisms induced by these challenges, especially through direct visualization of the failure processes. In this review, the recent progress on the mechanistic study of LMSSBs by in situ electron microscopy is summarized. In situ transmission electron microscopy (TEM) and scanning electron microscopy (SEM) offer an opportunity to probe the battery failure mechanism by observing the associated physical and chemical processes at nano/atomic resolution. The failure causes of Li dendrites growth and interphase formation are classified and discussed, followed by the corresponding solutions to address these issues. Additionally, the emerging perspectives on future research directions in this field are also summarized. [ABSTRACT FROM AUTHOR]

Aluminum metal is widely applied in the industrial sector because it has many advantages. FSSW welding is a method that can be used to join aluminum. The microstructural test results show the flow distribution of the zinc interlayer in the welding area. The flow of zinc material looks dominant in the steering zone area. The hardness test results for the connection with zinc interlayer had the highest value of 147HV. Highest shear tensile testing on joints using zinc interlayer. The use of zinc interlayer has been proven to significantly improve connection capabilities.

The novel Ti69NbCrZrX （X=Sn，W，Al，Mo，1%-2%， mass fraction） was used as an interlayer to join TiAl alloy with Ti2AlNb alloy by pulsed current diffusion welding at 900 ℃/30 min/8 MPa. The post-weld joint microstructure and properties were analyzed by SEM， EDS， EBSD， and room temperature tensile test. The results show that defect-free TiAl/Ti2AlNb joints can be obtained using Ti69NbCrZrX as the connecting interlayer. The joint interface microstructure is mainly composed of TiAl diffusion affected zone， interlayer diffusion zone， and Ti2AlNb diffusion affected zone. The TiAl diffusion affected zone structure is composed of white β phase and gray block α2 phase，the interlayer diffusion zone structure is mainly composed of gray block α2+ α phase， and white β/B2 phase composition， Ti2AlNb diffusion affected zone is composed of β/B2 matrix phase with lath and acicular O phase. The average value of room temperature tensile strength of the joint is 642.5 MPa， which reaches 91.57% of the strength of the base material. The fracture mode of the joints is dominated by brittle intergranular fracture， supplemented by brittle transgranular fracture.

AbstractThis study explores the potential of engineered interphases to enhance the performance of fiber-reinforced composites through an integrated approach combining theory, computation, and experiments. A theoretical axisymmetric modeling framework is introduced to evaluate stress distribution within a three-phase composite system subjected to axial pull-out loads. The composite comprises a cylindrical fiber embedded in a matrix with intermediate interphase whose modulus varies radially, following linear and power-law gradation profiles. A variational principle is employed to derive formulation for stress estimation across the composite components. To validate these theoretical insights, an axisymmetric finite element model incorporating a radially graded interphase is developed using a user-defined subroutine (UMAT) in ABAQUS. Comparative analysis demonstrates good agreement between theoretical predictions and finite element results. Notably, graded interphases reduce peak radial and shear stresses at the interphase by approximately 37% and 60%, respectively, compared to ungraded interphases. These predictions are corroborated by single-fiber pull-out experiments using specimens with stepwise modulus-graded interphases fabricated via an Object Connex260 PolyJet 3D multi-material printer. Experimental results confirm that graded interphases significantly enhance the composite’s load-bearing capacity and toughness by mitigating peak interfacial stresses. This study underscores the transformative potential of strategically engineered interphases in optimizing composite system performance, offering insights into advanced material design for high-performance applications. [ABSTRACT FROM AUTHOR]

This paper uses a Monte Carlo method to study the thermal conductivity of graphene nanoplatelet (GNP) composites. Firstly, a large number of GNPs are randomly set in a representative volume element. Then, based on a temperature satisfying the Laplace equation in a matrix, a coated surface (CS) is set up on each GNP surface, and the temperature of the CS and GNP can be obtained by the walk-on-spheres (WoS) method. Finally, the WoS method continues to be applied to calculate the heat flux density of the composite materials, further obtaining the thermal conductivity of the composites. We add the influence of interlayers in random walks. We incorporate the influence of interlayers in the WoS process, and the points that walk onto the interlayer surface have a very low probability of reaching the GNP due to the extremely low thermal conductivity of the interlayer. The calculated results are consistent with the experimental data. The model also studies the effects of the size, orientation, and aggregation of GNPs on the thermal conductivity of composite materials. [ABSTRACT FROM AUTHOR]

The article presents the results of shear testing during tensile loading of a layered material composed of: AA2519-AA1050-Ti6Al4V, before and after heat treatment. The described material was produced using a high-energy explosive welding method utilizing the detonation of ANFO (mixture of NH4NO3 and fuel oil). The research was based on monotonic loading of the material with increasing uniaxial load until separation between the gripping parts of the specimen was achieved. During the analysis of the research results, the obtained curves were compared, and a visual analysis of the obtained fractures was conducted. As a result of the conducted research, a significant impact of heat treatment on the described mechanical characteristics was demonstrated. The average value of maximum shear stresses decreased from 77.6 MPa for untreated specimens to an average of 66.3 MPa for heat-treated specimens. The heat treatment caused a slight but noticeable decrease in the tensile shear strength of the examined material. Fractures of the specimens obtained from the experiment confirm that, in studied cases, separation of individual fragments of specimens exhibited cohesive characteristics within interlayer material, regardless of whether material was heat treated. Results of this work is elimination of main doubts related to explosive welding of materials by indicating location of damage in technical objects. As demonstrated by the conducted research, in the case of the presented material, potential local post-weld delamination will not have a critical impact on the composite's strength. The separation-type damage is most likely to exhibit a cohesive nature within the mechanically weakest material (aluminum alloy 1050). [ABSTRACT FROM AUTHOR]

This study examines the Inconel 718/Ti6Al4V multi-material with a Cu and Nb interlayer produced by SLM. To achieve this, it is necessary to investigate the microstructure, the chemical and phase composition, and the hardness of the interfacial zone in the multi-material samples. Furthermore, it is necessary to determine the impact of interlayer utilization on the mechanical properties of multi-material samples. The investigation showed that the formation of island macro-segregation was observed in all interfacial zones of the multi-material samples. The interfacial zones, Ti6Al4V/Nb and Cu/Inconel 718, exhibited a relatively sharp transition in the chemical composition. In contrast, the Cu/Nb interfacial zone exhibited a gradual transition. The results of the chemical composition study indicated that the width of the Nb/Cu transition zone was approximately 700 μm. No new phases were identified in the production of the multi-material samples. The typical phases were present in the alloy zone, as well as in the Nb/Cu interfacial zone. During the transition from the Ti6Al4V zone to the Inconel 718 zone through the Nb and Cu zones, the average microhardness values changed as follows: 270 → 190 → 120 → 300 HV. The ultimate tensile strength values for the multi-material samples reached 910 MPa. [ABSTRACT FROM AUTHOR]

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Stability under light is critical for lead sulfide quantum dots (PbS QDs) in solar cell applications. To improve the stability of PbS QDs solar cells, the influence of the light illumination on the performance of the as-prepared PbS QDs solar cells was carefully investigated. Combined with X-ray and ultraviolet photoelectron spectroscopies, it was revealed that the 1,2-ethanedithiol (EDT) ligands of the hole transport p-type PbS QDs reacted with the ligands of the PbS QDs active layer under light illumination. The reaction not only undermines the n-type characteristics of the active layer, but also increases the number of defects, leading to a serious deterioration in device performance. An interface layer was introduced to block the EDT penetration to avoid this issue, significantly improving the stability of the device under light irradiation. Moreover, the separation of carriers was also enhanced due to the better matching the energy level of the interface layer. The device with an interface layer yielded a power conversion efficiency of 12.55% and sustained to a long time light illumination. [ABSTRACT FROM AUTHOR]

The present work aims to elucidate the effect of process parameters and pin length on microstructure and the characteristics, distribution of intermetallic compounds (IMCs), and associated failure initiation and progress pattern of AA7075 friction stir lap weld (FSLW) joints prepared employing copper interlayer. FSLW joints obtained using various combinations of tool rotation (900 and 1200 rpm), weld speeds (63 and 98 mm/min), and pin lengths (3 mm and 4 mm) are tested for tensile shear strength, fracture behavior, and the influence of IMCs formed are appraised. Further, the elastic modulus and hardness of the IMCs and neighborhood are evaluated using nanoindentation tests to correlate with the joint performance. The non-uniform thickness of AlCu, Al2Cu, and Al4Cu9 IMCs is formed due to intermixing of Al and Cu whose thickness varied with process parameters. Higher elastic modulus and hardness are recorded at the IMCs. FSLW joint prepared with 1200 rpm tool rotation, 63 mm/min weld speed, and 4 mm pin length results in better joint formation and higher strength, wherein an IMC layer thickness of around 3–4.3 µm is measured near the hook region. [ABSTRACT FROM AUTHOR]