Chemical Papers最新文献

Corrosion is the destruction of materials, usually metal, by a reaction with the environment, and is contrary to metallurgy, which depends on factors, such as environment, stress, temperature, and erosion. It is an important aspect in every form of life, from personal to professional spheres of life. It causes a huge loss to human health and the environment. Their method of synthesis is also ineffective. Therefore, the use of inhibitors becomes an effective method for protecting metals against corrosion. This paper aims to use inhibitors derived from plants as potential green corrosion inhibitors for an eco-friendly environmental input and plant-based-derived nanoparticles/materials that can also be used in various biomedical and engineering applications. In this paper, we present the corrosion problem in the environment, and industry and why plant extracts green inhibitors are a good alternative as corrosion inhibitors for corrosion control and prevention and where we can also, therefore, make improvements in the study by using plant-based nanoparticles as corrosion inhibitors as they are safe, less cost-effective and can be used in wide range.

This study screened the corrosion mitigation potential of quinoline derivative (QDCC) for Q235 steel protection in a 5 M HCl medium. The techniques used for examination include weight loss, electrochemical (100 mg/L to 400 mg/L), SEM/EDX, AFM, XPS, DFT, and MD. As QDCC doses increased, the corrosion prevention capacity was successfully improved. The PDP findings showed that QDCC functions as a mixed-type inhibitor, promoting the inhibition of both cathodic and anodic processes. The maximum and minimum charge transfer resistance (R_ct) and double-layer capacitance (C_dl) are 515.0 Ω cm⁻¹ and 186.0 μF/cm² with the addition of QDCC, indicating the corrosion inhibition mitigation. Temkin is the most accurately fitted isotherm that illustrates the chemical adhesion potential of QDCC upon the Q235 steel with ΔG^o_ads equals to − 43.49 kJ/mol. The surface study approaches like SEM/EDX, AFM, and XPS showed that the QDCC is strongly adhered over Q235 steel surface. The computation examination, which included DFT and MD, showed that neutral-QDCC forms are strongly adsorbing compared to protonated ones.

Macadamia is a key tree nut crop with global production surpassing 300,000 tons, and has created a significant amount of nut waste. Macadamia nut waste is constituted of 70–77% of the nut weight, and with inadequate disposal methods, this waste can pose a great threat to the environment. The chemical composition of macadamia nutshells is rich lignocellulosic materials, essential for bio-based applications such as biofuels, bioplastics, biocomposites, and other industrial uses. By valorizing macadamia nut waste into high-value products, environmental impacts can be mitigated to reduce disposal costs, and enhance the economic value of byproducts. This review also emphasizes the importance of innovative waste management strategies and explores the feasibility of utilizing macadamia nut waste in various applications. Therefore, macadamia nut waste can be an abundant and valuable and precursor for green economy and sustainable development.

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In this study, graphene oxide (GO) structure was doped with metallic silver (Ag) atoms in vacuum environment (10^–6 Torr) at 200 K. GO and GO/Ag samples were analyzed using X-ray diffractometry (XRD), scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and optical and electrochemical impedance spectroscopy (EIS). XRD patterns showed that the samples investigated grew in the hexagonal structure (2θ = 9.4°). However, reflection peaks originating from Ag were observed in the XRD patterns of GO/Ag samples. SEM images showed that there was an increase in grain size and layer number in the GO structure with Ag doping. Bond vibrations originating from carbon, oxygen and hydrogen atoms were observed from the FTIR spectra. In addition, I_D/I_G ratios of GO and GO/Ag samples were calculated and found to be 0.89 and 0.82, respectively. From optical measurements, it was seen that surface plasmon resonance (SPR) event occurred at 430 nm wavelength in GO/Ag samples. Electrical properties of samples were examined under different wavelength beams (room, 366 nm and 450 nm) during measurement using EIS method (“Room” refers to the normal lighting in the room environment.). The lowest charge transfer resistance was observed in GO/Ag sample illuminated with 450 nm wavelength. Then, solutions containing GO and GO/Ag were prepared and two different diode structures were produced by spraying them onto p-Si crystal surface by chemical sputtering method. Characteristics of diodes in dark and light environments (100 mW/cm²) were examined, and it was seen that diode-containing Ag exhibited better photovoltaic values.

Due to declining fossil fuel reserves and increasing petroleum costs, finding cost-effective alternatives for beneficiating high-ash coal is essential. Coal’s inherent hydrophobicity makes froth flotation a favorable technique, with diesel typically used as the collector. This study explores the use of pyrolysis oil (PP oil), derived from non-biodegradable polypropylene packaging waste, as a sustainable alternative to diesel in non-coking coal flotation. The research employed a central composite design (CCD) to assess the flotation performance of PP oil as collector and optimize the flotation process by identifying the influence of significant factors. Under optimized flotation conditions employing 6 ml of pyrolysis oil and 1 ml of methyl isobutyl carbinol (MIBC) as frother, the process achieved a clean coal yield of 71.25%. The ash content was effectively reduced from 34.6% in the feed to 12.38% in the product, demonstrating the efficacy of the reagent combination in enhancing separation performance. Analysis of variance (ANOVA) and regression analyses evaluated the impact of process parameters on yield and ash content, while Fourier-transform infrared spectroscopy (FTIR) analysis assessed the presence of functional groups in the PP oil that facilitate its collector functionality. Replacing traditional diesel with PP oil in coal flotation offers a significant step toward a more sustainable and potentially more economical coal beneficiation process.

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This study investigates the mechanical properties of hybrid polymer composites reinforced with glass and basalt fibers, and enhanced with hybrid nanofillers, silicon dioxide (SiO₂) and multi-walled carbon nanotubes (MWCNTs). The aim is to optimize and statistically predict mechanical performance using Box-Behnken Design (BBD) integrated with Response Surface Methodology (RSM). Four key processing parameters: filler content (0–2%), sonication time (10–30 min), molding pressure (5–15 MPa), and mold holding time (24–72 h) were varied at three levels. Using the BBD matrix, 29 composite samples were fabricated via hand lay-up and compression molding, with a stacking sequence of 01B/02G/02B/02G/02B/02G/01B. Vickers hardness and flexural modulus (GPa) were measured per ASTM D785 and D790 standards. Regression models were validated through ANOVA, showing strong alignment between experimental and predicted results. Maximum values of flexural modulus 16 GPa and hardness 22 HV were observed at filler (2%), sonication (20 min), mold pressure (15 MPa), and mold hold time (48 h.). Predicted optimized values were flexural modulus 15.975 GPa and Vickers hardness 21.950 HV using Design-Expert 13.0. Results show improvements of 45% in modulus (from 11 to 16 GPa) and 29% in hardness (from 17 to 22 HV). SEM analysis revealed typical failure modes such as matrix cracking, debonding, fiber rupture, and pull-out.

Nanostructured electrode materials are a promising area of study due to the impending energy demands of subsequent generations caused by our excessive reliance on fossil fuels. The long life, high power density and many environmental and financial advantages of supercapacitors make them an innovative, eco-friendly energy storage solution. This  work describes the MoS₂/g-C₃N₄ (MS/GCN) electrode material’s structural development and electrochemical performance. The material was prepared using a hydrothermal process, which resulted in a notable increase in specific capacitance (C_s) and exceptional long-term stability throughout cycling. Physical tests like, Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), X-ray diffraction can study the physical properties of manufactured electrode. Electrochemical study of manufactured materials was assessed using, galvanostatic charging/discharging (GCD), chronoamperometry (CA), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). MoS₂/g-C₃N₄ (MS/GCN) composite exhibited C_s was 818.27 F/g at 1 A/g current density (J_d) with power density (P_d) of 390 W/Kg and energy density (E_d) of 69.13 Wh/kg. The composite remained stable for 50 h after the 5000th cycle, demonstrating high cyclic stability. This work demonstrated that fabricated MS/GCN is an outstanding for energy storage devices.

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Although various substances have been used to coat chemical fertilizers to slow or control their release, finding the best substance and optimal performance conditions is still essential. The granular chemical fertilizer (N20, P5, K10) was coated using four kinds of bio-oil (prepared by the pyrolysis method) and the results were compared. Straw bio-oil had better coating properties on the surface of the chemical fertilizer. According to the IC analysis results, the amount of nutrients released from chemical fertilizer coated by straw bio-oil decreased by 78.5% in the first 24 h in comparison with the core fertilizer. To find better conditions for the coating process, chemical fertilizer granules were coated with straw bio-oil at three different temperatures (400 ℃, 500℃, and 600 ℃). Finally, the results showed that coating chemical fertilizer with straw bio-oil at 600 ℃ could improve the quality of the covering layer.

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Oxymethylene ethers are considered for use as components of fuels and lubricants. They can be obtained from renewable raw materials, and their properties can be tailored by modifying the structure of the terminal alkyl groups. This paper presents the results of a study on the synthesis of oxymethylene ethers from 2-ethylhexanol and paraformaldehyde. High efficiency in the synthesis has been demonstrated by shifting the thermodynamic equilibrium through azeotropic distillation of water formed during the reaction. The process achieves a high alcohol conversion rate (up to 95%), with near-100% selectivity toward the target ethers. The formation of oxymethylene ether from high molecular weight alcohols is more sensitive to water than light alcohols. Under similar conditions, water reduces the methanol conversion to oxymethylene ethers by half, while the reaction with 2-ethylhexanol is almost completely suppressed. It has been shown that oxymethylene ethers with 2-ethylhexyl terminal groups are suitable as components of specialty lubricants due to their excellent low-temperature properties, resistance to hydrolysis, and viscosity dependence on the molecular weight distribution.

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