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Failure assessment diagrams (FADs) are essential engineering tools for evaluating the structural integrity of components. However, their widespread application can be limited by complexity and computational expense. This study presents a novel machine learning-based approach to streamline FAD analysis, offering accuracy and efficiency while overcoming these limitations. The approach integrates numerical contour integral-based FADs with artificial neural networks (ANNs). To ensure reliable material modeling for the Finite Element Analysis (FEA) used to generate J -integral based FADs that train the ANNs, careful experimental and numerical procedures were employed. This involved uniaxial tensile tests, an iterative method for obtaining precise true stress–strain curves, and a Ramberg–Osgood material model for accurate material behavior representation. The ANNs themselves not only analyze large datasets to generate precise FAD envelopes but also predict limit loads and the Φ parameter, incorporating the effect of residual stress on the FAD methodology. To verify and test the proposed method, hypothetical fitness-for-service assessment cases were conducted, incorporating experimental residual stress measurements from split-ring tests on P110 and L80 pipes. These assessments were compared to both traditional FAD methods and computationally intensive FEA-based FADs. Results demonstrate a closer agreement with FEA-based calculations than traditional methods provided in engineering standards. Ultimately, this work provides a rather innovative and adaptable approach for structural integrity evaluations and critical engineering assessments through the proposal of an ANN enhanced FAD approach, simplifying these calculations while maintaining high fidelity. • Developed an ANN-based approach for streamlined Failure Assessment Diagram (FAD) analysis. • Integrated ANNs with numerical FADs, enabling precise envelope generation from extensive datasets. • Conducted experimental residual stress measurements using split-ring test data as an input for hypothetical fitness-for-service (FFS) evaluations. • Demonstrated superior accuracy of the ANN-based FAD methodology for enhanced fitness-for-service (FFS) evaluations. [ABSTRACT FROM AUTHOR]

• Effect of minimal surface-lattice core topological features on the impact properties of a sandwich structure. • Cell size and relative density of minimal surface-lattice core show exponential growth with impact properties of sandwich structures. • The high shear resistance of periodic primitive TPMS topology contributed to improved perforation limit. • Stochastic and spinodoid-based lattice sandwich panels are damage tolerant. Recent advancements in 3D printing technologies have made it possible to fabricate intricate lattice architectures with high precision. These lattices can now be utilized to design lightweight sandwich structures that serve multiple functions. To enhance the impact loading performance of these structures, it is crucial to understand how the lattice's topological properties, particularly those with minimal surface attributes like periodic or stochastic Primitive and Gyroid triply periodic minimal surfaces (TPMS) and spinodal-like stochastic cellular materials, associate with the mechanical properties of sandwich structures while keeping the skin thickness fixed. Thus, this paper explores the low-velocity impact behavior of various sheet/shell-based minimal surface-latticed cores of sandwich structures with woven composite skins. The elasto-plastic-damage numerical simulations consider lattice core periodicity, randomness, and anisotropy while keeping the relative density constant. Core lattice randomness and anisotropy are designed using the Gaussian Random Field (GRF) method for spinodal-based stochastic cellular materials and stochastic TPMS. The simulation results showed that the periodic Primitive-lattice core exhibits high out-of-plane shearing strength, enabling the sandwich structure to demonstrate the highest perforation limit. GRF spinodal-based core achieved the highest peak load due to its anisotropic mechanical properties. However, the post-yielding bending of the lattice sheet limited its ability to resist perforation, and absorb and dissipated energy. Interestingly, the stochastic Gyroid TPMS topology, with its inherent densely-distributed microstructure, showed high sensitivity to loading rate, resulting in enhanced energy absorption and dissipation of the sandwich structure. These findings offer valuable insights for optimizing multifunctional sandwich structures with superior impact performance and their design for additive manufacturing. [Display omitted] [ABSTRACT FROM AUTHOR]

We provide a novel investigation that demonstrates the synthesis of silver-doped bismuth oxide (ABO), holmium-doped bismuth oxide (HBO), nanostructured bismuth oxide (BO), and silver-holmium co-doped bismuth oxide (CDBO) by a cost-effective and straightforward surfactant-assisted co-precipitation technique. In comparison to the BO, ABO, and HBO samples, the optical tests revealed that the CDBO sample exhibited superior photocatalytic characteristics. This is possibly attributed to the physical, optical, and structural properties of the material tailored by the synergistic effect of the adopted strategies, i.e., nanotechnology, oxygen vacancies, and co-doping. The microstructures, physicochemical properties, morphological characteristics, and compositional attributes of the synthesized materials were investigated using sophisticated characterization techniques. The intrinsic conductivity of the bismuth oxide was enhanced with the incorporation of Ag and Ho as co-dopants, as shown by the results obtained from two probe current-voltage experiments. The co-doped sample exhibited the highest efficacy in decomposing rhodamine B dye, with a degradation rate of 91 % during a mere 70-min exposure to W-lamp illumination. The most ideal settings for CDBO photocatalytic activities were identified by comprehensive parameter optimization research. These parameters include a basic pH, a catalyst dosage of 25 mg, a dye concentration of 15 ppm, and an operating temperature of 30 °C. The co-doped and nanostructured photocatalyst also showed an outstanding capability to break down orange II and phenol dye. The trapping experiments' results indicate that the hydroxyl and superoxide radicals play a significant role in the mineralization of the tested dye. [Display omitted] • Co-doped Bi 2 O 3 NPs have been prepared via wet route. • Synthesized samples were characterized via PXRD, FTIR, SEM, BET, and I–V studies. • Co-doping create structural defects and reduced the band gap. • Current-voltage study confirms improved current conductivity. • Co-doped Bi 2 O 3 effectively mineralized the RhB, Orange II and phenol dye. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pyramidal lattice structures (PLS) with I-shaped struts were 3D printed via DLP. • The utilization of I-shaped struts led to an increase in energy absorption of up to 68%. • Lateral buckling of the lattice struts was observed in the tailored PLS. • The measurements and observed collapse modes were in good agreement with FE predictions. • Specific cross-sectional designs can achieve enhancements in strength of up to 93%. This study examines the compressive response of geometrically tailored pyramidal lattice structures composed of struts with I-shaped cross-sections. Geometrically tailored pyramidal lattices with micro-scale features are 3D printed using the Digital Light Processing (DLP) technique, and their effective elastic modulus, collapse strength and energy absorption capacity are experimentally evaluated under quasi-static compressive loading. Furthermore, detailed non-linear finite element (FE) calculations are performed to examine underlying collapse mechanisms and explore the vast design space offered by the proposed geometrical tailoring scheme. Both the experimental and numerical results show that the geometrically tailored lattice structures outperform conventional pyramidal lattices of equal weight in terms of elastic modulus (+24 %), collapse strength (+21 %) and energy absorption (+68 %). Notably, these strength improvements are attributed to lateral buckling that prompts the I-shaped struts to bend sideways during collapse. Specific cross-sectional designs demonstrate remarkable enhancements in strength and energy absorption, reaching up to 93 % and 161 %, respectively, differentiating them significantly from conventional designs. [ABSTRACT FROM AUTHOR]

Because of their many advantages, such as simplicity of handling, affordability, and environmental friendliness, green magnetic nanoparticles (GMNPs) are currently receiving more attention than prevailing magnetic nanoparticles (MNPs). The synthesis and application of GMNPs inspired by biological systems are encouraged by rising ecological consciousness and stringent environmental restrictions and also deal with in detail in this manuscript. The current report presents the biological and environmental uses of GMNPs in-depth. Numerous biomedical applications, including imaging and diagnosis, cancer therapy, immunoassay, genetic engineering, and supported enzymes (proteins and peptides), among others, successfully use GMNPs. The GMNPs would be coupled with tiny sensors, microsystems, and microfluidics modules to boost the signal sensitivity for the identification of environmental contaminants, diseases, poisons, drugs, and trace biomarkers from clinical, environmental, and dietary examples. The GMNPs were essential elements in gene delivery and gene therapy initiatives, among other genetic engineering endeavors. They have also been extensively used for environmental applications such as wastewater treatment, organic pollutants decontamination, electrochemical sensing, industrial and radioactive wastes treatment, pollutant adsorption and removal etc. The use of GMNPs, particularly biosynthesized MNPs, is also believed to be more cost-effective than the majority of regularly used traditional MNPs. In addition, Green magnetic nanoparticles applied as supported enzymes, proteins and peptides catalyst, positron emission tomography, computed tomography, magnetic resonance imaging, theranostics, thermo-chemotherapy, electrochemical immunoassay and efficient detection of coronavirus is a significant issue in modern analytical chemistry and other fields. The opportunities of using GMNPs in the place of traditional MNPs have also been proposed. [ABSTRACT FROM AUTHOR]

Herein, lanthanide ion (Gd+3) doped Bismuth Molybdate (Bi 2 MoO 6) integrated on the rGO sheets has been prepared as a novel photocatalyst (Gd@Bi 2 MoO 6 /rGO) for the photocatalytic treatment of toxic pollutants. Different physiochemical, optical, electrical, thermal, and electrochemical properties of Gd@Bi 2 MoO 6 /rGO, along with its counterparts (Bi 2 MoO 6 and Gd@Bi2MoO6), were studied through XRD, SEM/TEM, FT-IR, UV/Vis, I-V, TGA, Mott-Schottky, and EIS measurements. Photocatalytic experiments revealed that Gd@Bi 2 MoO 6 /rGO exhibited significantly enhanced photocatalytic activity, achieving 96.2 % photo-degradation of Methylene Blue with 120 min of irradiation, which is 6.5 and 3.1 times higher compared to Bi 2 MoO 6 (40.9 %) and Gd@Bi 2 MoO 6 (64.8 %), respectively. Moreover, Gd@Bi 2 MoO 6 /rGO demonstrated a notable photocatalytic efficiency of 81.7 % towards Ciprofloxacin, significant as per the existing literature benchmark. The enhanced photocatalytic activity is ascribed to the in-built Gd+3 redox centers, high electrical conductivity (7.35 × 10−3 S/m), favorable flat band potential (-0.81 V), and low semiconductor impedance (R ct = 51.71 Ω and R s = 0.90 Ω). Additionally, the electron-capturing ability of lanthanide dopant ions and S-C heterojunction of Gd@Bi 2 MoO 6 /rGO facilitates the separation of photo-generated e-/h+ pairs and favors high concentrations of ROS. The results obtained highlight the potential of Gd@Bi 2 MoO 6 /rGO for applications in photocatalysis and wastewater treatment. [Display omitted] • Gd doped Bi 2 MoO 6 have been prepared via hydrothermal route. • Gd@Bi 2 MoO 6 NPs were reinforced with rGO using ultrasonication approach • Synthesized nanocomposite showed exceptional light harvesting aptitude. • The impedance study confirms the improved charge transport properties. • Newly developed nanocomposite effectively degrades organic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quaternary ammonium copolymers having different hydrophilicity/hydrophobicity are tested as casing and tubing corrosion inhibitors. • Polymeric surfactants with higher hydrophobicity showed better protection potential than surfactants with higher hydrophilicity. • They become effective by adsorbing on the metal surface using their hydrophilic segments, and their adsorption follows Langmuir isotherm. • Polymeric surfactants retards both anodic and cathodic reactions and mainly behave as cathodic-type inhibitors. • DFT study suggests that quaternary nitrogens deprotonate and coordinate with the metallic surface using their unshared electron pairs. In this study, two quaternary ammonium-based copolymers (DAC-DAD10 and DAC-DAD20) with varying hydrophilicity/hydrophobicity are synthesized, characterized, and their capacity to suppress P110 carbon steel (P110 CS) corrosion in 3.5% NaCl is examined. DAC-DAD10 and DAC-DAD20 were synthesized using diallylammonium chloride (DAC) and N1, N1-diallyl-N6-dodecyl-N6, N6-dimethylhexane-1,6-diaminium dichloride (DAD) and their inhibition potential (%IE) and mechanism were studied by different experimental and computational methods. The outcomes suggest that the %IE of DAC-DAD10 and DAC-DAD20 increases on increasing the hydrophobicity as DAC-DAD20, having a large hydrophobic alky chain, showed relatively better %IE than DAC-DAD10. DAC-DAD10 and DAC-DAD20 manifest the best %IE of 88.68% and 96.17%, respectively, at concentrations as low as 3 mgL-1. Potentiodynamic polarization studies indicate that they behave as cathodic-type inhibitors. Their adsorption on the metallic surface followed the Langmuir adsorption isotherm. Various surface analyses, including SEM-EDS, and XPS, confirm that they adsorb at the metal and electrolyte interface and build a corrosion protective layer. DFT study suggests that quaternary nitrogen atoms easily deprotonate and coordinate with the metallic surface using their unshared electron pairs. The corrosion inhibition based on experimental and computational analyses is schematically presented and described. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous bone plates with cubic (C), diamond (BCC) and body-centered cubic (CBCC) structures were prepared. • Axial compression, torsional and bending tests were carried out to check the designs' reliability. • CBCC structure with enhanced performance was used with varying rows' and porosities. • Finite element analysis was used to check the biomechanical performance of bone plates. • Increased porosity enhanced the callus volume but displayed poor mechanical performance. The current study investigates the biomechanical performance of porous bone plates augmented with three different cellular lattice structures, e.g., body-centered cube (BCC), simple cube (SC), and the superposition of simple and body-centered cube (SC-BCC) structures. The SC-BCC cellular structures, exhibiting improved torsional, compression, and bending stiffness, were strategically integrated into the bone plates. Configurations ranging from one to three rows, with porosity ranging from 30% to 90%. Increasing the number of rows and porosity maximized the interfragmentary movement at the fracture site. Specifically, SC-BCC configurations with one, two and three rows at 90% porosity demonstrated callus volume improvements of 31.33%, 42%, and 43.2%, respectively, compared with the lowest callus volume observed with SC-BCC at one row and 30% porosity. Regardless of the improved volume, callus stiffness was highest at 30% and 90% porosity levels across all cases, indicating more mature tissue formation in calluses and better physiological load support. High stresses located at 90% porosity, followed by 50% porosity, discouraged their mechanical performance. Therefore, employing 30% porosity configurations with appropriate vertical rows for desired movement is recommended for optimal biomechanical performance. However, 90% porosity may be suitable in scenarios involving minimal forces and restricted patient movement. [ABSTRACT FROM AUTHOR]