Key Engineering Materials Vol. 928

Abstract: Copper is used in diesel engine injectors and bearings, among other places. The corrosion and mechanical characteristics of these components when they are exposed to biodiesel are still lacking acceptable information. Nonetheless, there is a dearth of data on the corrosion and mechanical qualities of these components when exposed to alternative fuels such as biodiesel. In this study, waste-oil-derived biodiesel (WBB100) was blended with diesel fuel (WBB0) in the following proportions: B100:B0–10, 20, and 40 (WBB10, WBB20, and WBB40). ASTM standards were used to determine the blends' characteristics. Copper corrosion was investigated in a biodiesel environment using a stationary immersion method. Corrosion and surface morphology differences between the corroded and unexposed copper coupons were evaluated. After 960 hours of exposure, it was discovered that copper exposed to B0 (0.147 mpy) corroded less than copper exposed to B100 (0.4601 mpy). WBB10, WBB20, WBB40, and WBB100 had Brinell hardness values of 204.319, 221.666, 245.711, 267.021, and 293.303 N/mm², respectively, while their tensile strengths were 694.69, 753.64, 835.42, and 907.87 MPa. As a result, it can be determined that the WBB10 blend is a better substitute for WBB0 in terms of biodiesel properties and corrosion features.

Abstract: The 7020-aluminum alloy is a lightweight and high strength material which is widely used in aerospace industries where the damage tolerance, the factor of safety and environmental induced fatigue is very high. The low density and better mechanical properties enable its applications in industries over conventional engineering materials. In the present work, the fatigue crack growth (FCG) behavior of the pre-corroded 7020-aluminum alloy was investigated. The samples were subjected to an aqueous solution of sodium chloride; the micro-hardness was optimized and the significance of corrosion on FCG was studied in the context of bending stress, the number of cycles (N) to failure/fatigue life and microstructure. The solution treated samples at a temperature of 520°C for 3 hours provided the maximum hardness. However, the hardness of samples was optimum for 3 hours of solution heat treatment and minimum for 2 hours of solution heat treatment. It is suggested that the precipitation of the metastable phase affected the hardness. In the initial stage, the fatigue life of pre-corroded samples was significantly lower as compared to as-received samples. However, at the later stage, it became less significant but still, the pre-corroded sample showed lower fatigue life. Both types (pre-corroded and as-received) of samples showed a similar trend as fatigue life decreases with increasing bending stress. The fractured microstructure of the pre-corroded sample showed scratches on the surface which were produced during mechanical rubbing of the specimen pieces during plastic deformation under load. However, the microstructure at the edge of the notch showed "volcano-mouth" features" which indicated the phenomena of galvanic corrosion. The galvanic corrosion envisages due to deposition on the 7020-aluminum alloy and the impurities in the alloy. The elements Fe, Si, C and Mn existed as impurities that induced the galvanic corrosion and an elliptical corrosion pit was observed.

Abstract: Using a green synthesis approach, we have synthesized SnO₂ nanoparticles. The morphology of the nanoparticles are characterise by scanning electron microscopy. The UV-vis spectroscopy technique was used to study the optical characteristics. The different parameters such as dosage of catalyst, initial concentration of drugs, effect of pH and other parameters were estimated. The Visible light was irradiated over sample solution at different pH values, and the photo-catalytic effect of the SnO₂ nanoparticle was observed for degradation of ciprofloxacin drugs. The absorption spectra showed a stronger absorption peak at 273 nm representing the ciprofloxacin drugs. The photo-generated electron of nanoparticles degradation drugs, which shows decrease absorption intensity. The results revealed that the photo-catalytic degradation process works well at pH 7. The higher degradation efficiency was observed by following the pseudo-first-order kinetics.

Abstract: The 2-Dimennsionnal nanocomposites are applied for the ennhannced fluorescence sensor for analysing heavy metal ions is explored using a simple novel technique based on green manufactured (CQDs@MoS₂) nanocomposite. The emission intensity of CQDs have a better dispersibility, and MoS₂ nanosheets have an excellent exfoliation, allowing the CQDs to adhere to the surface and form a label-free sensors. The emission peak of CQDs was quenched by transferring non-radiative energy as of CQDs to MoS₂ sheets in an excited state. However, when metal ions are included in the CQDs@MoS₂ nanocomposite, it develops a solid surface combined with the carbon dots nanosheets, that might aid in CD recovery. More intriguingly, the sensing performance of MoS₂ nanosheets were examined at various pH levels to better recognize the change in surface charge, which resulted in significantly improved responsiveness for identification of Pb (II) ions with LODs of 0.9 nM. Furthermore, it is suggested that present method are intended to be quick, easy, cost effective, environmental friendly for sensing heavy metal ions.

Abstract: The increase in exhaust of CO₂ gas has created a undesirable change into atmosphere, which leads to global warming and unfavourable climatic change. Therefore capturing for CO₂ gas has become a global anxiety. Coal-mine stations generate the majority of the world's electricity, Stakeholders environmentalists, and Researchers have paid close attention to CO₂ capturing using combustion technology using a variety of technological alternatives such as membrane separation, adsorption, absorption, and chemical loop combustion in presence and absence of oxygen. Meso, Micro and porous adsorbents can be used to collect carbon from exhaust gases. Carbonaceous MOF and non-carbonaceous and mesoporous adsorbent for CO₂ capturing under various pore size and surface area are discussed in this study. The mesoporous adsorbents and non-carbonaceous micro are also being studied in chemical loop combustion with in situ CO₂ capture at elevated heat (>400 °C). The mechanics of adsorption, material properties, and synthesis techniques are all explored. Isosteric temperatures and characterization approaches are discussed. The prospects for improving the techno-economic feasibility of carbon capturing systems by combining them with CO₂ to create industrial essential compounds such as ammonia and urea are investigated.

Abstract: For the creation of chromogenic agents, an exogenous catalyst can be used, which can enhance complexity and interfere with the colorimetric detection of Deltamethrin (Dmp). This study revealed that MnO₂/SnO₂ nanocomposite to mimicked peroxidase activity, leading to the devel Deltamethrinment of a simple and reliable sensing system containing ATCh-TMB-H₂O₂ for the selective and sensitive assay of AChE activity and its inhibitor Deltamethrin, which is described in detail in another publication. As acetylcholine hydrolysis was shown to modify the peroxidase-like activity of acetylcholine, this activity was used to measure Deltamethrin with exceedingly sensitively with a low limit of (LOD) of 4.0 ng mL^-1. The AChE inhibition allowed for the detection of Deltamethrin with a low-order. The real-world samples can be successfully identified using this method.

Abstract: When comparing the photo-catalytic degradation of Rhodamine b dye azo dye, TiO₂-Cu₂O was shown to be much more efficient. Additionally, the effects of several parameters on the dye concentration, including pH, degradation rate of dye solution, and irradiation time, were examined. Rhodamine b dye's ability to aggregate was also investigated using UV-Vis spectroscopic techniques, which were utilised in conjunction with other approaches. The revival of the TiO₂-Cu₂O catalyst was also examined.

Abstract: The Cu-MOF has outstanding catalytic activity because of its capacity to buffer oxygen. As a result, when added to diesel fuel, this additive reduces nitrogen dioxide emissions while also oxidising hydrocarbon emissions. The current study examines the impact of Cu-MOF nanoparticles on diesel engine efficiency and emissions. The SEM, and XRD methods were utilised to characterise the nanoparticles of Cu-MOF, which were generated by chemical approach. In a two-step method, Cu-MOF was combined with diesel using a conventional ultrasonic shaker in order to get a stable suspension, Extensive experiments using ASTM-standard testing procedures have also examined the impact of nanoparticles on several physicochemical parameters of diesel fuel. For the purpose of examining the impact of nanoparticles on engine efficiency and emissions, a diesel engine load test was conducted. Also included are side-by-side comparisons of fuel qualities with and without additives.

Abstract: Nowadays life style practices demand more packed foods in the market around the world. In this trend increases the demand for researches on developing new packaging materials. In this research focuses novel AA8079/ SS304/ Wood ash hybrid nanocomposites development for meeting packaging related applications. The materials like aluminum alloy AA8079 (matrix material) obtained from waste food cans, Nanoparticles of stainless steel SS304 and Nanoparticles of Wood ash which obtained from waste bamboo woods were utilized to compose through stir casting process. Two set of Six different novel AA8079/ SS304/ Wood ash hybrid nanocomposites by varying the reinforcement from 0 wt.% to 10 wt.% with the step of 2 wt.% in the AA8079 matrix. The prepared composites included for examinations to test their Ultimate Tensile strength, yield strength, percentage of elongation, shear strength and hardness properties. Apart from this, the effect of heat treatment and annealing on strength of developed novel AA8079/ SS304/ Wood ash hybrid nanocomposites were investigated.