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Reduced graphene oxide is a modified form of graphene oxide used for gas sensing due to its large surface area and exceptional electrical conductivity. It is suitable for detecting various gases, including carbon dioxide, nitrogen dioxide, ammonia, ethanol and volatile organic compounds. Graphene-based materials have shown promise in gas sensing due to their sensitivity, selectivity, and cost effectiveness. Graphenebased sensors are versatile and can be easily integrated into existing systems, making them suitable for various industrial applications. The adjustable characteristics of graphene enable customization and modification of sensor performance, expanding its potential in gas sensing technology. The main goal of this study is to make metal oxide nanomaterials and reduced graphene oxide using a straight forward chemical method. Samples will be analyzed using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, UV-vis spectroscopy, and X-ray photoelectron spectroscopy. The research aims to assess the performance and efficacy of these nanocomposites compared to other materials in energy storage, catalysis, and sensing applications. The study also explores the parameters affecting gas detection abilities, surface chemistry, and electrical interactions. [ABSTRACT FROM AUTHOR]

In all cases, the three-component reaction produced excellent yields (mean yield 96%). The reaction yield increased with an increase in catalyst amount from 2 mol% to 10 mol%, but catalyst loading beyond 10 mol % showed no improvement in the reaction yield. CeO SB 2 sb nanoparticles (NPs) have received a great deal of attention in recent years due to their numerous applications in a variety of fields such as catalysis,[1] ceramics,[2] fuel cells,[3] gas sensors,[4],[5] solid-state electrolytes,[6] ceramic biomaterials,[7] chemical-mechanical polishing (CMP),[8] and ultraviolet absorbtion.[9] The CeO SB 2 sb nanomaterial is an excellent catalyst due to its oxygen storage and release capacity (OSC) via the redox shift between Ce SP 4+ sp and Ce SP 3+ sp under oxidizing and reducing conditions.[10],[11] Different morphologies of CeO SB 2 sb nanomaterials for catalytic activity have been investigated.[1],[11] Numerous nanostructures of CeO SB 2 sb have been prepared and used as catalysts, including nanoparticles, nanotubes, nanowires, nanorods, nanocubes, and nanospindles. To evaluate the effect of temperature on the reaction yield, the model reaction was conducted at different temperatures with an optimized catalyst loading. [Extracted from the article]

The study of the stretching sheet has extensive applications in the field of engineering and technology. Hence, the objective of the present study is to deal with the impact of pertinent parameters on Williamson fluid across a stretchable nonlinear sheet when chemical reaction, varied thermal radiation, and heat source/sink are present. Partial differential equations are used to model the resulting scenario, and after adding the necessary similarity variables, a system of nonlinear ordinary differential equations is formed using flow equations. The reduced ODEs are tackled by applying the fourth-order RK-scheme together with shooting methodology, and the impacts of different system parameters are examined corresponding to the fluid’s velocity, energy, and concentration profile. The important findings are discussed using graphics and they are as follows: As magnetism increases, fluid velocity rises but falls with an increment in buoyancy; the temperature falls with a boost in Grashof number but rises with an inclination in Prandtl number; and fluid reaction concentration declines with the boost in chemical parameter and Schmidt number but rises with an increment in thermophoresis, heat source/sink, and Brownian motion parameter. [ABSTRACT FROM AUTHOR]

CoCeO2 NPs were successfully synthesized and confirmed using x‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and high‐resolution transmission electron microscopy (HRTEM) techniques. The catalytic performance of the synthesized CoCeO2 NPs catalyst was examined during the one‐pot multicomponent synthesis of biologically significant 2‐amino‐3‐cyano‐4H‐pyran derivatives. The reaction was easily accomplished using a one‐pot, three‐component reaction of dimedone, aryl aldehydes, and malononitrile in ethanol under reflux, with excellent yields and a short reaction time. The current catalytic system is more appealing because of its simple reaction conditions, uncomplicated product isolation, economic feasibility, and reusability of the catalyst free from significant loss of activity. This process offers an effective strategy for the synthesis of 2‐amino‐3‐cyano‐4H‐pyran derivatives. [ABSTRACT FROM AUTHOR]

The morphological studies of fishes are vital for enhancing our knowledge about biodiversity, ecology, evolution and fisheries management. The research aims to study the morphological features of Siganus vermiculatus along the Maharashtra coast. Specimens were collected from three distinct viz., Raigad (Alibag), Ratnagiri (Ratnagiri) and Sindhudurg (Malvan) were analyzed for their morphological traits. The morphological studies showed minor variations in the posterior body depth and head shape of the S. vermiculatus specimens from different locations. [ABSTRACT FROM AUTHOR]

Cobalt oxide thin films are successfully synthesized by sol‐gel spin coating method. The XRD study shows that the cobalt oxide thin films annealed at 400°C exhibit cubic polycrystalline structure. SEM images show a well adherent and uniform formation of cobalt oxide thin films with nanosized grains‐like morphology. From the optical study, the direct optical band gap values of as‐deposited and annealed cobalt oxide films are found to lie between 1.42–2.05 and 1.36–1.94 eV. The absorption coefficient of the cobalt oxide is found to be in the order of 104 cm−1. High refractive index of cobalt oxide indicates that it can be used as one of the layers in multilayer antireflection coatings. [ABSTRACT FROM AUTHOR]

Pristine and Co-doped ZnO (CZ) nanocapsules (NCs) have been successfully prepared using a simple and cost-effective co-precipitation method. The effect of 1–4 at.% Co-doped ZnO (C1Z–C4Z) samples on physicochemical and hazardous NO2 sensing performance were investigated and reported. The structural, morphological, spectral and compositional properties studied by XRD, FESEM and EDX, TEM, BET, FTIR, UV–Visible absorption spectroscopy and XPS techniques specify the phase formation of ZnO and doping of Co atoms into ZnO lattice. The NO2 gas sensing properties of CZ samples were studied at 120–280 °C operating temperature and 5–100 ppm concentration. The sensing results showed that the 3 at.% Co-doped ZnO (C3Z) sensor exhibited highest (286%) gas response with fast response/recovery time (3/319), stable, selective and reproducible towards 100 ppm NO2 gas at 200 °C operating temperature. Such types of materials are very promising for the fabrication of NO2 gas sensors. [ABSTRACT FROM AUTHOR]

With the enhancement in science and technology, necessity of complex shapes in manufacturing industries have become essential for more versatile applications. This leads to the demand for lightweight and durable materials for applications in aerospace, defense, automotive, as well as sports and thermal management. Wire electric discharge machining (WEDM) is an extensively utilized process that is used for the exact and indented shaped components of all materials that are electrically conductive. This technique is suitable in practically all industrial sectors owing to its widespread application. The present investigation explores WEDM for LM6/fly ash composites to optimize different process variables for attaining performance measures in terms of maximum material removal rate (MRR) and minimum surface roughness (SR). Taguchi’s L27 OA design of experiments, grey relational analysis, and analysis of variance (ANOVA) were employed to optimize SR and MRR. It has been noted from ANOVA that reinforcement (R) percentage and pulse on time are the most influential aspects for Grey Relational Grade (GRG) with their contributions of 28.22 and 18.18%, respectively. It is found that the best process variables for achieving the highest MRR and lowest SR simultaneously during the machining of the composite are gap voltage of 30 V, pulse on time of 10 µs, pulse off time of 2 µs, wire feed of 8 m/min, and R of 9%. The predicted GRG is 0.84, and the experimental GRG value is 0.86. The validation experiments at the optimized setting show close agreement between predicted and experimental values. The morphological study by optical microscopy revealed a homogenous distribution of reinforcement in the matrix which enhances the composite’s hardness and decreases the density.

In this study, the stagnation point flow of a magnetized Williamson fluid past a stretching sheet in the presence of nonlinear thermal radiation and buoyancy effect is studied. The present situation is remodeled using similarity transformation that transforms the flow model of partial differential equations into the set of nonlinear ordinary differential equations. The fourth‐order Runge‐Kutta scheme and shooting method are employed to solve these reduced equations. The effects of various associated parameters over the velocity and temperature profiles are plotted and the outcome of each associated parameter is discussed through graphs. The key findings are noted as follows: the velocity profile declines with an increase in the magnetic force number, and an increment in buoyancy parameter leads to the increase in the boundary layer thickness and decrease in the thickness of the thermal boundary layer. [ABSTRACT FROM AUTHOR]

Buoyancy forces result from the cooling or heating of a continuous stretching sheet, which causes a change in the resulting flow and thermal fields, and hence the heat transfer behavior in the manufacturing process. The study of the thermal buoyancy induced in boundary layer flow is important due to its recent advances in the areas of nuclear energy, electronics, and space technology. In this perspective, the aim of the present study is to investigate the effect of the buoyancy parameter on the magnetohydrodynamics boundary layer flow over an exponentially stretched sheet in the presence of nonlinear thermal radiation and porous media. Using similarity transformation, the flow model of partial differential equations is transformed into a set of coupled nonlinear ordinary differential equations. The efficient fourth‐order Runge‐Kutta scheme with the shooting method is used to solve the reduced equations. The impact of various associated parameters on velocity and temperature profiles were analyzed and computed through graphs. The major outcome of the present study shows the enhancement in the velocity distribution with the increase in the buoyancy parameter. Also, the increase in thermal buoyancy and thermal radiation leads to an increase in fluid temperature. Moreover, it is worth to note that the fluid velocity declines with the augmentation of the magnetic parameter. [ABSTRACT FROM AUTHOR]

An engine bracket is one of the most critical components of the engine used for mounting and supporting the engine in the vehicles. Today, the automobile industry requires lightweight components, which will reduce the car's overall weight when fitted into the vehicle. Topology optimization is a technique with the help of which the surface of a component is optimized to get the required shape for having reduced weight. The weight is reduced by optimizing the material on the surface of the details. In this paper, the work done is the application of topology optimization on the surface of the engine bracket arm. Then the optimized model is tested computationally using realistic conditions. Bi-directional evolutionary structural optimization is used as a technique for topology optimization. With the help of the BESO method, the material optimization is done, and then the weights are compared with the original component. A new algorithm is developed using MATLAB codes. The sensitivity ratio is considered using the von Mises strength as a critical parameter for the BESO method for optimization. The optimized bracket model is then assembled with the hub of the component, and then the assembly is simulated for verification using standard conditions. A comparison of weight reduction is there using topology optimization.

The academic performance assessment of students helps teachers, administrators, and policymakers to initiate corrective measures on academically poor students. This paper revisits the Zadeh-Deshpande formalism for evaluating students’ answer scripts using the concept of the reliability of information (degree of confidence) via the “degree of match” and fuzzy inference system in students’ performance evaluation. The case study infers that the overall performance of all the students is “average”. Furthermore, 206 of 237 students (87%) are declared as “average” with “high degree of certainty” by the evaluators (teachers). The aim of the proposed method is not to replace the traditional method of evaluation. Instead, the proposed technique is a step forward to enrich the present system of students’ performance assessment. Policymakers can use this method as it provides reliable information. A comparison between the results obtained from the academic performance of students using multiexpert and single-expert systems is also discussed in the paper.

The abrasive characteristics of LM6 alloys are difficult to machine, so designing a technology that allows for effective machining is essential. This paper aims to evaluate the effect of process variables, namely feed rate, spindle speed and drill material, towards the responses like Thrust force, Surface roughness and burr height when drilling of LM6 alloy. LM6 aluminium alloy was fabricated by the stir casting process. Experiments were conducted using L9 orthogonal array in a Vertical Machining Centre coupled with a dynamometer for measuring thrust force. Surface roughness was found by Surface roughness tester and burr height was measured using Vision Measuring System. The findings show that the created model can accurately estimate the thrust force (TF), surface roughness (SR) and burr height (BH) in LM6 alloy drilling within the parameters examined.

This study performed a steady-state numerical analysis to understand the temperature in different heat sink configurations for LED applications. Seven heat sink configurations named R, H-6, H-8, H-10, C, C3, and C3E3 were considered. Parameters like input power, number of fins, heat sink configuration were varied, and their influence on LED temperature distribution, heat sink thermal resistance and thermal interface material temperature were studied. The results showed that the temperature distribution of the H-6 heat sink decreased by 46.30% compared with the Cheat sink for an input power of 16 W. The result of the H-6 heat sink shows that the heat sink thermal resistance was decreased by 73.91% compared with the Cheat sink at 16 W. The lowest interface material temperature of 54.11 °C was achieved by the H-6 heat sink when the input power was used 16 W. The H-6 heat sink exhibited better performance due to more surface area with several fins than other heat sinks.

The examinee and the examiner play pivotal roles in the educational grading system. Students’ academic performance evaluation by multiple experts involves epistemic uncertainty, which can be modeled using a fuzzy set theory. How many evaluators/experts are almost similar in their perceptual subjective evaluation of the students answer paper? In other words, how many experts are reliable for a particular evaluation task with a defined possibility level? In this paper, the focus is on object’s features (students’ marks) as a basis in the subjective evaluation process to identify the degree of similarity among the domain experts. The case study reveals that 11 out of 20 evaluators are similar in their decision making of students’ academic performance with possibility (α-level cut, 0.98). The inter-rater reliability (κ-coefficient) among the selected 11 teachers is 0.41, which signifies a fair/moderate agreement in the evaluation process. This paper proposes an approach that is useful for the selection of experts having similar perceptions in judgment. This paper demonstrates a case study showing how it is useful to educational policy makers in the selection of examiners.

The endodontic file is a tapered, needle shape body used for the preparation of curved human root canals. During the preparation, process files get failed due to the locking action offered by the canal wall. The present study aimed to find the fatigue life of endodontic files at 23°, 33° and 43° root canal curvature angles. Four brands of files were selected for the present study viz. Hyplex CM, Pro-Taper Next, Hero Shaper, Pro-File Vortex. The strain life analysis done using ANSYS showed that the Hyplex CM file gives the highest fatigue life at 23°, 33° and 43° root canal curvature angles. Therefore, Hyplex CM file was selected for DoE Taguchi Optimization study. Each experimental reading was conducted on X Smart Plus experimental setup under purely rotary and combined reciprocating-rotary motion, at 500 rpm, 600 rpm and 700 rpm and 23°, 33° and 43° root canal curvature angles. Hyplex CM file given maximum fatigue life at 23° root canal curvature angle and 500 rpm speed of rotation. But if file motion is combined rotary-reciprocating, life reduces. The ANNOVA study showed that P-value and significance F are very small, which represented that the regression model is effective.

The oxide dispersion strengthened (ODS) ferritic steels are one of the most important in fuel cladding materials for 4th Generation nuclear reactors because of their excellent mechanical properties such as irradiation resistance, swelling resistance, and elevated temperature tensile/compressive strength. Mechanical alloying (MA) is one of the most promising routes for developing nanocrystalline ferritic ODS steel materials. For the production of nanocrystalline ferritic ODS steel powders, the most influencing factor is the milling speed and milling time during the mechanical alloying process. With the improper selection of milling time and speed, the final milled powders become an amorphous structure consisting of high impurity inclusions in the microstructure, and strength was also affected. In order to overcome these drawbacks, the present investigation was taken into account for the selection of appropriate mechanical milling speed and time, which was optimized through Taguchi analysis followed by the MA process. The optimized mechanical milling speed and time of milled powders were characterized through X-Ray Diffraction Analysis (XRD) and Scanning Electron Microscope (SEM).

Selective inhibition sintering (SIS) process intends to produce near-net-shape components through sintering of specific region of powder particles. The prediction of surface quality in SIS parts is a challenging task due to its complex part building mechanism and influence of abundant process parameters. Therefore, this study investigates the key contributing parameters such as layer thickness, heater energy, heater feedrate and printer feedrate on the surface quality characteristics ( R a , R z and R q ) of high-density polyethylene specimens fabricated through selective inhibition sintering process. The SIS system is custom built and experiments are conducted based on four-factor, three-level Box–Behnken design. The empirical models have been developed for predicting the influence of selected parameters on surface quality. The optimal process parameters such as the layer thickness of 0.1 mm, heater energy of 28.48 J/mm 2 , heater feedrate of 3.25 mm/s and printer feedrate of 110 mm/min are attained using grey relational multi-criteria decision-making approach. Furthermore, response surface analysis revealed that surface quality of sintered components is influenced significantly with heater energy and heater feedrate, followed by layer thickness. The confirmation experiments based on optimal process variables validate the developed grey relational analysis strategy.

Steering knuckle connects steering system, suspension system and braking system to the chassis. The steering knuckle contributes a significant weight to the total weight of a vehicle. Increasing the efficiency of an automobile without compromising the performances is the major challenge faced by the manufacturers. This paper presents an effective topology optimization of steering knuckle used in a vehicle with the primary objective of minimizing weight. The study on optimization of knuckle is divided into two phases, the first phase involves making of a computer-aided design model of the original steering knuckle and carry out finite element analysis on the knuckle by estimating the loads, which are acting on the component. In the second phase, design optimization of the model of steering knuckle is carried out, and excess material is removed at the region where induced stress is negligible as obtained in finite element analysis assuming standard boundary and loading conditions. The paper describes a research work carried out to optimize structural topology giving the essential details. The methodology may be applied to optimize structural components used in applications where the ratio of desired properties to the cost, generally in terms of weight, is to be optimized. In the case of automobiles, strength to weight ratio has to be maximized. New researchers working in the area will have an understanding of the procedures, and further, the techniques may be applied to design in general.

Abstract Background The green fluorescent protein has revolutionized many areas of cell biology and biotechnology since it is widely used in determining gene expression and for localization of protein expression. Expression of recombinant GFP in E. coli K12 host from pBAD24M-GFP construct upon arabinose induction was significantly lower than that seen in E. coli B cells with higher expression at 30°C as compared to 37°C in E. coli K12 hosts. Since OmpT levels are higher at 37°C than at 30°C, it prompted us to modify the OmpT proteolytic sites of GFP and examine such an effect on GFP expression and fluorescence. Upon modification of one of the two putative OmpT cleavage sites of GFP, we observed several folds enhanced fluorescence of GFP as compared to unmodified GFPuv (Wild Type-WT). The western blot studies of the WT and the SDM II GFP mutant using anti-GFP antibody showed prominent degradation of GFP with negligible degradation in case of SDM II GFP mutant while no such degradation of GFP was seen for both the clones when expressed in BL21 cells. The SDM II GFP mutant also showed enhanced GFP fluorescence in other E. coli K12 OmpT hosts like E. coli JM109 and LE 392 in comparison to WT GFPuv. Inclusion of an OmpT inhibitor, like zinc with WT GFP lysate expressed from an E. coli K12 host was found to reduce degradation of GFP fluorescence by two fold. Results We describe the construction of two GFP variants with modified putative OmpT proteolytic sites by site directed mutagenesis (SDM). Such modified genes upon arabinose induction exhibited varied degrees of GFP fluorescence. While the mutation of K79G/R80A (SDM I) resulted in dramatic loss of fluorescence activity, the modification of K214A/R215A (SDM II) resulted in four fold enhanced fluorescence of GFP. Conclusions This is the first report on effect of OmpT protease site modification on GFP fluorescence. The wild type and the GFP variants showed similar growth profile in bioreactor studies with similar amounts of recombinant GFP expressed in the soluble fraction of the cell. Our observations on higher levels of fluorescence of SDM II GFP mutant over native GFPuv in an OmpT+ host like DH5α, JM109 and LE392 at 37°C reiterates the role played by host OmpT in determining differences in fluorescent property of the expressed GFP. Both the WT GFP and the SDM II GFP plasmids in E. coli BL21 cells showed similar expression levels and similar GFP fluorescent activity at 37°C. This result substantiates our hypothesis that OmpT protease could be a possible factor responsible for reducing the expression of GFP at 37°C for WT GFP clone in K12 hosts like DH5α, JM109, LE 392 since the levels of GFP expression of SDM II clone in such cells at 37°C is higher than that seen with WT GFP clone at the same temperature.