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Abstract Metal‐insulator‐insulator‐metal (MIIM) diodes with thickness‐gradient films for the insulator layers are fabricated for the first time. Spatially varying atmospheric‐pressure chemical vapor deposition is used to deposit ZnO and Al2O3 films with orthogonal gradient directions, producing 414 MIIM diodes with 414 different ZnO/Al2O3 film‐thickness combinations on a single substrate for combinatorial and high‐throughput optimization. The nm‐scale ZnO/Al2O3 films are printed in only 2 min and the entire device fabrication takes 7 h, which is much less than conventional approaches for investigating many insulator‐thickness combinations. Rapid identification of the optimal thickness combination is demonstrated; high‐performance diodes (asymmetry = 227, nonlinearity = 13.1, and responsivity = 12 A/W) are observed when a trap‐assisted tunneling mechanism is dominant for insulator thicknesses of 3.4–4.4 nm (ZnO) and 7.4 nm (Al2O3).

In the last few decades, tremendous effort is given to the production of various polymers and polymeric composites components through innovative polymer processing techniques. Fused deposition modeling (FDM) of polymers as a printing technique in additive manufacturing has been explored extensively due to its cost-effectiveness, manufacturing capabilities, flexibility in material selection, and dimensional accuracy. A few reviews of the literature have been done to investigate various applications for polymers, but none have focused on the research on commercial and in-house generated polymers and polymeric composites, particularly those made using the FDM printing technology. Consequently, the study data on the internal development of polymer and polymeric composite filament-based FDM printing is gathered and processed in this work. The work also highlights various types of polymeric composites and recycled polymeric composites with their detailed material characteristics. In addition, various applications of FDM printing of polymeric composites at the industrial scale and domestic level usage are highlighted as the potential to reduce carbon emission through the effective recycling process.

The Parallel Tubular Channel Angular Pressing Process (PTCAP) has emerged as a promising method for refining the grain structure and enhancing the mechanical properties of metallic materials through severe plastic deformation. This study focuses on a comprehensive investigation of the PTCAP process, combining experimental and numerical analysis to gain insights into its underlying mechanisms. Experimental investigations involve processing a commercially pure copper tube using PTCAP under controlled conditions. In parallel, an explicit numerical analysis is developed using ABAQUS software to simulate the deformation behavior during PTCAP. The model incorporates material constitutive equations and accounts to describe the material response under high strain rates and large deformations. The research aims to investigate how multi-pass PTCAP affects hardness, strain homogeneity, and stress distribution. A comparison between the load punch from the experimental and FEM is conducted to validate the FEM results, and there is a good correlation between both. Hardness measurements are conducted at various stages to quantify the changes in material hardness resulting from the successive PTCAP passes. The hardness of the Cu tube increased by 63.45, 94.51, 103.98, and 105.64% after 1 to 4 passes, respectively.

This study investigates the friction stir welding (FSW) of aluminum alloy 7075-T651, mainly focusing on managing heat generation during the process. The critical parameters influencing heat amount and the material flow including FSW tool shoulder diameter (SD) and travel speed (TS) were investigated. Two far different SD of 10 mm and 20 mm with constant pin diameter (PD) of 5.70 mm that resulted in PD: SD ratios of 1:1.75 and 1: 3.50, respectively, were employed. Furthermore, three different travel speeds of 25, 50, and 75 mm min ^−1 at a constant rotation rate of 600 rpm were used in combination with the two PD: SD ratios. The macrographic and radiographic results indicated that the smallest PD: SD ratio has successfully achieved sound friction stir welded (FSWed) joints for the same travel speeds. Results also indicated that a significant amount of material deformed under a high PD: SD ratioat a high TS of 75 mm min ^−1 , while flash increased with reducing PD: SD ratio.Mechanical properties were compared, revealing that hardness in the nugget zone (NZ) decreased with a lower TS of 25 mm min ^−1 . A small PD: SD ratioallowed for more symmetrical heat distribution, supported by the hardness map. The ultimate tensile strength decreased with increasing TS, and the highest ultimate strength, reaching 319 MPa, was observed with a 1:1.75 ratio and TS of 25 mm min ^−1 . X-ray diffraction analysis (XRD) found an increase in peaks with increasing shoulder diameter and the number of peaks increased with decreasing travel speeds.

The aim of this study is to investigate friction stir welding (FSW) to join A304 austenitic stainless steel and low carbon steel A283 Gr. C in-lap configuration to clad the carbon steel with highly corrosion-resistant stainless steel. Thus, a wide range of FSW parameters were investigated such as FSW tool rotation rate from 200 to 400 rpm, tool traverse speed from 25 to 75 mm/min, and vertical forces of 20 to 32 KN. The FSW parameters combination of high welding rotation rate (400 rpm) and high vertical forces (32 KN) results in rejected joints in terms of surface appearance and clear surface defects. On the other hand, rotation rates of 200 and 300 rpm with different welding speeds and vertical forces resulted in some sound joints that were further investigated for microstructure and mechanical properties. The sound lap joints were examined via optical microstructure, SEM, and EDS investigations. For the mechanical properties, both tensile shear testing and hardness testing were used. The transverse macrographs showed intermixing between the two dissimilar materials with an almost irregular interface. The hardness profile in both materials showed a significant increase across the different regions from the Base Material (BM) to the nugget zone, with a maximum value of 260 Hv in the stainless steel and 245 Hv in the carbon steel. This increase is mainly attributed to the grain refining in the weld region due to the dynamic recrystallization and transformations upon the thermomechanical cycle. The tensile shear load of the joints varied from 20 to 27 KN for the FSWed joints, with the highest joint tensile shear load of 27 KN for that produced at 300 rpm tool rotation and 25 mm/min welding speed.

Background: Labor pain is a severe form of agony that females experience while giving birth. A lot of pregnant women prefer epidural anesthesia (EA) to avoid labor pain. Objective: This study focuses on women's general awareness about EA during the childbearing age. Methods: A cross-sectional, hospital-based study was conducted using a self-administered questionnaire. The study included all females of childbearing age getting routine antenatal care. The survey was designed to measure their awareness toward EA. A total of 328 females participated in the study. Of these, 205 (62.5%) women showed a low level of knowledge toward EA. Data were analyzed using the Chi-square test and Independent Samples t-test. Results: Participants in our study included 328 women of childbearing age. Most women (172 [52.4%]) participating in the study were aged between 30 and 40 years. In terms of education, 204 (62.2%) women had university-level education. Two hundred and ninety (88.4%) women were multipara. The majority of women (205 [62.5%]) had a low-level knowledge about EA with a significant relationship between the level of perception and primary education, as well as postgraduation with P < 0.023 and P < 0.001, respectively. Also, previous EA with pregnancy significantly related to the level of knowledge with P < 0.001. Through past pregnancies, 106 (32.3%) women had experience with EA. Of these, EA caused complications in only 13 (12.3%) women and side effects in 29 (27.4%) women. Conclusion: The majority of women of childbearing age had limited knowledge about the benefits and complications associated with EA. During the antenatal visit, it is essential to educate all women about EA. This could be done by the obstetrician, anesthesiologist, or midwives and/or through flyers and brochures.

This study aims to investigate the feasibility of hydroforming (HF) technology coupled with response surface optimization for producing high-quality five-branched AISI 304 stainless steel tubes with different diameters, addressing the shortcomings of traditional manufacturing processes. Conventional techniques often result in issues with multiple consumables, low precision, and subpar performance. The research focuses on finding optimal forming parameters for a more effective process. Initial attempts at a five-branched tube proved unfeasible. Instead, a multi-step forming approach was adopted, starting with the formation of the upper branch tube followed by the two reducing lower branch tubes, a strategy termed "first three, then five". This method, enhanced by a subsequent solid solution treatment, yielded promising results: the combined height of the upper and lower branches was 141.1 mm, with a maximum thinning rate of 26.67%, reduced to 25.33% after trimming. These outcomes met the product usage requirements. Additionally, the study involved designing and developing dies for manufacturing five-branched tubes with different diameters using servo HF equipment. The effectiveness of the multi-step forming process and parameter combinations was confirmed through experimental validation, aligning closely with the FE simulation results. The maximum thinning rate observed in the experiments was 27.60%, indicating that FE simulation and response surface methodology can effectively guide the production of high-quality parts with superior performance. [ABSTRACT FROM AUTHOR]

This research investigates the effects of the frequency of the external electric field during the curing process on the interfacial properties of epoxy composites reinforced by Mendong fiber. Epoxy was used as a matrix with cycloaliphatic amine as a curing agent. The AC electric field by frequencies of 1, 2, and 3 kHz and strength of 750 V/cm were applied during the curing process. The functional groups, structure, interface properties, and morphology of treated epoxy were observed using Fourier‐transform infrared, x‐ray diffraction, scanning electron microscope, and pull‐out test, respectively. The result indicates that after treatment with an electric field of 1 kHz, new peaks were observed in the epoxy diffractogram at the angle of 6.2° and 12.3°, change in morphology, the wettability properties of epoxy were increased and interface shear strength was improved. Increasing the frequency of electric fields results in more damage to the interface and subsequently reduces the shear strength at the interface. Highlights: Interface properties of the composite after curing in an electric field characterized.Exposure to electric field frequency during curing changed epoxy properties.Shear strength of Mendong fiber/epoxy varied post‐exposure to the electric field. [ABSTRACT FROM AUTHOR]

This comprehensive study investigates the viscoelastic behavior, thermal transitions, and self‐healing efficiency of microcapsule‐based composites with and without a catalyst. The composites consist of urea‐formaldehyde/dicyclopentadiene microcapsules embedded in an epoxy matrix, with the addition of Grubbs' catalyst. Our research examines the impact of repetitive dynamic mechanical analysis (DMA) testing and the presence of Grubbs' catalyst on the composites' self‐healing efficiency and dynamic mechanical properties. Using laser microscopy, optical microscopy, Fourier‐transform infrared spectroscopy, and thermogravimetric analysis, we employ various characterization techniques to enhance our understanding of the composite behavior. The findings emphasize the importance of evaluating self‐healing efficiency through DMA, which is a reliable, expeditious, and non‐destructive method. The results show that incorporating Grubbs' catalyst significantly enhances the self‐healing performance of the composites, effectively mitigating the degradation of mechanical properties due to aging. Furthermore, the inclusion of catalyst particles improves stiffness, rigidity, and energy dissipation characteristics, facilitating the self‐healing process. However, careful consideration is necessary to balance mechanical properties and the glass transition temperature when designing self‐healing composites. This study demonstrates a promising self‐healing efficiency of approximately 73% and 44% in the second and third DMA tests, respectively, for composites containing microcapsules and Grubbs' catalyst. [ABSTRACT FROM AUTHOR]

Several agro-wastes are rich in natural fibers and finds scope to be used as reinforcement in composite industry. These natural fibers have some advantages over man-made fibers, including low cost, light weight, renewable nature, high specific strength and modulus, and availability in various forms worldwide. In this paper, the effect of surface modification of leaf sheath coconut fiber (LSF) (an agro-waste) reinforced in phenol formaldehyde matrix composites with silicon carbide (SiC) nano particles as filler material were investigated for its mechanical characteristics. The investigation portrays that coconut LSF (CLSF) modified with potassium permanganate reinforced polymer composite with SiC nano particles as filler material exhibited 18.86%, 22.54%, 10.72% and 15.43% higher tensile, flexural, hardness and impact characteristics respectively compared to the unmodified CLSF reinforced polymer composite. The results reveal that the surface modification treatment considerably increased the mechanical characteristics of the composite. [ABSTRACT FROM AUTHOR]

Background: Urinary parcel contamination (UTI) is thought to be related with expanded maternal and fetal grimness and mortality; consequently, a legitimate evaluation of information and practices is pivotal to figure out preventive techniques to guarantee the wellbeing of both the mother and the child. Methods: The study decided the information, disposition, rehearses (KAP), and the convictions of pregnant females about UTI in view of the Health Belief Model. A study survey was utilized to accumulate information from pregnant females with and without UTI. The relationship of the pregnant females' sociodemographic qualities with their KAP and wellbeing convictions was resolved utilizing Pearson's chi-square test. Results: Consequences of the review showed that most of pregnant females have unsuitable information with an uplifting outlook and great clean practices against UTI. Instructive capability and financial status showed a huge relationship with the KAP of pregnant females. Uplifting perspective and acceptable sterile practices were clear among the respondents notwithstanding their unacceptable information. Conclusion: Nonetheless, the class just regularly incorporates subjects, for example, the significance of going to pre-birth and post pregnancy check-ups, birthing, breastfeeding, infant screening, and advancing the division's projects. UTI and its anticipation among pregnant females are not considerably shrouded in the mother's class. [ABSTRACT FROM AUTHOR]

This study investigates the potential of Tin Slag Polymer Concrete (TSPC) strengthening through confinement using basalt fiber reinforced polymer (BFRP) and aramid fiber reinforced polymer AFRP) confinement. TSPC short cylindrical column samples have been wrapped with BFRP and AFRP in a single layer (30 mm overlap) using Sikadur-330 epoxy and final samples were coded as TSPC-UC, TSPC-BF and TSPC-AF for unconfined, BFRP and AFRP for confined respectively. After curing for 30 days at room temperature, compressive test has been performed to know the strength, modulus, strain, fracture energy and failure modes of unconfined and confined TSPC. Test result shows that AFRP confinement (114.24 MPa) provide more upsurge in strength enhancement compared to BFRP (81.52 MPa). Fracture energy value of TSPC-AF (821.18 J) is higher than TSPC-BF (538.66 J), but compressive modulus of TSPC-AF (3.23 GPa) is lower than TSPC-BF (4.32 GPa). In addition, yield stress value of TSPC-AF (80.71 MPa) is higher than TSPC-BF (57.21 MPa). Moreover, stress-strain curve and failure mode has shown that TSPC-AF exhibit higher degree of brittleness compared to TSPC-BF. Finally, it is noticed that there are some similarities in strength augmentation of TSPC amid BFRP and glass fiber reinforced polymer (GFRP) as well as between AFRP and carbon fiber reinforced polymer (CFRP) confinement. [ABSTRACT FROM AUTHOR]