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Purpose: This paper presents the approximate limit pressure solution for shape-imperfect and through-wall circumferential cracked (TWCC) 90° pipe bends at the intrados region. Finite element (FE) limit analysis was used to estimate the limit pressure by considering the small geometrical change effects. Design/methodology/approach: Three-dimensional (3D) geometric linear FE methodology was implemented to investigate the limit pressure of structurally deformed TWCC 90° pipe bends. The material considered in the analysis is elastic perfectly plastic (EPP). The limit pressure of TWCC shape-distorted pipe bends was predicted from the corresponding internal pressure when von-Mises stress was equal to or just exceeded the material's yield strength for all the models. The theoretical solution which was published in the literature was used to evaluate the current FE approach. Findings: Ovality Co and TWCC at the intrados region caused a considerable impact on pipe bends, while the thinning? Ct produced a negligible effect and hence was not included in the analysis. With the combined effect, the bend portion of pipe bend experiences substantial influence, and the TWCC effect consequently increases with 45o, 60o and 90o crack angles and decreases the limit pressure of pipe bends. An improved closed-form empirical limit pressure solution was proposed for TWCC shape-distorted pipe bends at the intrados region. Originality/value: In the limit pressure analysis of 90° pipe bends, the implications of structural irregularities (ovality and thinning) and TWCC have not been examined and reported. [ABSTRACT FROM AUTHOR] more...

The study assesses the efficacy of CeO2 nanoparticles synthesised via the hydrothermal method for UV‐induced catalytic activity in decomposing cobalt complexes. Various analyses, including X‐ray diffractometry (XRD), Raman spectroscopy, scanning electron microscopy (SEM), high‐resolution transmission electron microscopy (HR‐TEM), and UV‐Vis spectrophotometry were employed to investigate the impact of cobalt on cerium oxide's morphology, optical, electrochemical, and microstructural characteristics. The XRD analysis revealed a cubic structure in the fluorite‐type pattern, primarily oriented along the (111) direction. Raman spectroscopy supported these findings, identifying an active mode peak at 464 cm−1 and indicating the presence of F2g cubic fluorite. SEM imaging displayed cleavage and uniform, densely packed grains. Elemental analysis confirmed the presence of Ce, O, and Co, corroborated by X‐ray Photoelectron Spectroscopy (XPS) data. Optical measurements indicated a band gap starting at 3.03 eV, which decreased with increasing Co ratio, reaching 2.9 eV at 4 % cobalt incorporation. Furthermore, cyclic voltammetry experiments demonstrated that Co‐doped samples exhibited enhanced ion storage capacity. These comprehensive analyses underscore the potential of Co‐doped CeO2 nanoparticles for UV‐induced catalytic activity, offering valuable insights into their structural and functional properties. [ABSTRACT FROM AUTHOR] more...

This review article analyses the research articles submitted for past one decade in various combinations of materials in thermal barrier coated engines. Thermal insulation materials have a major impact on the efficiency of automotive engines. More efficiency is expected to increase the operating temperature. This paper examines the different aspects and applications of the thermal insulation materials. The system has an impact on fuel consumption, fuel efficiency, and pollution content and fatigue life of an engine components. The thermal insulationon the top layer of the piston decreases thermal conductivity that increases the unburned oxidation of fuel, decreasing in thermal tension of the engines by exposing the metal substrates at low peak temperature. The article discusses the performance, merits and de-merits of TBC. [ABSTRACT FROM AUTHOR] more...

Over the past few decades, metal oxides have attracted significant research attention due to their wide-ranging applicability in nearly every field of study. In the present study, we focus on photochemical reactions promoted by using nanoscale MoO3, TiO2 and MoO3/TiO2 nanocomposite. The nanocomposite facilitated charge separation and elevated photo-destruction efficiency of [Cu(dien)(1-MeIm)Cl]Cl complex in a mixed solvent medium via an interlayer pathway. The synthesized complex and the nanomaterials were validated by various instrumental techniques. The lifetime of charge carriers (τ = 36 ns) is higher than bare materials proving its superior photo efficacy. Introduction of 40% acetonitrile (ACN:H2O) solvent gave a higher photoreduction rate constant for Cu(II) complex by MoO3/TiO2 (5.733 × 10–2 s−1) denoting the better photocatalytic nature of nanocomposite rather than the prepared bare nanomaterials. The findings from the study unambiguously reveal that even a small amount of surface incorporation significantly shifts the material for blue LED application. Thus, it paves the way for unleashing its diverse uses, comprehending its distinctive attributes and investigating its possibilities. [ABSTRACT FROM AUTHOR] more...

Nano CeO2/SnO2 composite was successfully synthesised using the hydrothermal method and is one of the most widely used photocatalysts in metal-oxide semiconductors and has good photocatalytic activity. Experimental and spectroscopic approaches confirmed the structure and shape of the nanocomposite according to XRD, HR-TEM and SEM results. Spectral peaks are shown to migrate with the CeO2/SnO2 composite in experiments using Raman and opacity (photoluminescence). The magnetic properties of the composite were thoroughly investigated. The different oxidation states of Ce and Sn, which act as active sites in the electrocatalytic activity of this nanocomposite material, were observed using X-ray photoelectron spectroscopy. The capability of the CeO2/SnO2 composite was demonstrated by additional galvanic charge–discharge (GCD) experiments at various current densities, cyclic voltammetry (CV) measurements at different scan rates (the maximum capacitance value of 718 F g−1 from CV and 721 A g−1 from GCD). Reduction of cis-[Co(phen)2Cl2]Cl by nano-CeO2/SnO2 was traced for the production of Co(II) ion, which was shown to be catalytically efficient by UV–Vis response curves. Thus, the enhanced photocatalytic activity of the nano-CeO2/SnO2 material can be attributed to the excellent charge separation and electron transport for the reduction efficiency of the photogenerated charge carriers. [ABSTRACT FROM AUTHOR] more...

This study uses a three-dimensional nonlinear finite-element method to investigate the effects of bend angle (ϕ) and shape imperfection on the collapse load of pipe bends subjected to in-plane opening bending moment using large displacement analysis. ABAQUS was used to create a pipe bend model, whereas by virtue of symmetry about the longitudinal axis, half of the pipe bend model was built. The bend angle was varied from 30° to 180° with an interval of 30°, and shape imperfections, namely ovality (C o) and thinning (C t), were varied from 0% to 20% each at 5% intervals. Elastic-perfectly plastic is thought to be the material of choice for the pipe bend. The results show that the bend angle has a significant impact on the collapse load of pipe bends between 30° and 120°, after which a significant decline was observed. The ovality impact increases with an increase in bend angle for pipe bends with a large thickness, whereas the opposite effect was found for smaller thicknesses with a small bend radius. The effect of bend radius and thickness was significant for large bend angles. Thinning (C t) and thickening (C th) have no effect on collapse load. A new mathematical equation has been proposed to predict the integrated effect of bend angle and shape imperfection. [ABSTRACT FROM AUTHOR] more...