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This study focuses on the synthesis and application of glycerol carbonate (GC) as an emulsifier for light crude oil. GC was synthesized from glycerol and dimethyl carbonate via transesterification, achieving a 90% yield. Characterization through 1H-NMR, 13C-NMR, and FT-IR confirmed its structure. The emulsification properties of GC were tested by mixing it with light crude oil and water, demonstrating effective emulsification and forming stable emulsions. Stability tests with GC concentrations of 60/40, 70/30, and 80/20 revealed that emulsions remained stable for over 24 h. A particle size analysis indicated that higher GC concentrations produced smaller droplet sizes, enhancing the emulsification efficiency. This study highlights the potential applications of GC in oil spill remediation and enhanced oil recovery, emphasizing its biodegradability and low toxicity as environmental benefits. Overall, GC is presented as an effective and eco-friendly emulsifier for light crude oil, offering stable emulsions and promising industrial applications.

Cellulose nanocrystals (CNC) were obtained from Typha domingensis (an invasive macrophyte) collected from lagoons and wetlands in Altamira, Mexico. Cellulose extraction was carried out by a treatment with aqueous NaOH in a batch reactor followed by NaClO-bleaching and subsequent hydrolysis with sulfuric acid. The fibers were characterized by Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The crystallinity of the cellulose fibers isolated from Typha domingensis increased from 29 % (not treated fibers) to 73 % and the beginning of thermal degradation increased from 246 °C to 312 °C before and after the bleaching. The CNCs isolated from this plant show average values of 20 nm in diameter and 190 nm in length. Micrographs of the Typha domingensis fibers and the cellulose isolated therefrom as well as bleached cellulose indicate the removal of hemicellulose, lignin, and waxes from the fibers, which corroborates the XRD and FTIR results.

A novel bio-inspired algorithm, namely, Dingo Optimization Algorithm (DOA), is proposed for solving optimization problems. The DOA mimics the social behavior of the Australian dingo dog. The algorithm is inspired by the hunting strategies of dingoes which are attacking by persecution, grouping tactics, and scavenging behavior. In order to increment the overall efficiency and performance of this method, three search strategies associated with four rules were formulated in the DOA. These strategies and rules provide a fine balance between intensification (exploitation) and diversification (exploration) over the search space. The proposed method is verified using several benchmark problems commonly used in the optimization field, classical design engineering problems, and optimal tuning of a Proportional-Integral-Derivative (PID) controller are also presented. Furthermore, the DOA’s performance is tested against five popular evolutionary algorithms. The results have shown that the DOA is highly competitive with other metaheuristics, beating them at the majority of the test functions.

The purpose of the present work was to prepare polypropylene (PP) matrix composited filled with chemically treated pistachio shell particles (PTx), and evaluate their effect on the composites’ thermal properties. PP-PTx composites were formulated in different PTx content (from 2 to 10 phr) in a mixing chamber, using the melt-mixing process. The PTx were chemically treated using a NaOH solution and infrared spectroscopy (FTIR). According to thermogravimetric analysis (TGA), the treatment of pistachio shell particles resulted in the remotion of lignin and hemicellulose. The thermal stability was evaluated by means of TGA, where the presence of PTx in composites showed a positive effect compared with PP pristine. Thermal properties such as crystallization temperature (Tc), crystallization enthalpy (∆Hc), melting temperature (Tm) and crystallinity were determinate by means differential scanning calorimetry (DSC); these results suggest that the PTx had a nucleation effect on the PP matrix, increasing their crystallinity. Dynamic mechanical analysis (DMA) showed that stiffness of the composites increase compared with that PP pristine, as well as the storage modulus, and the best results were found at a PTx concentration of 4 phr. At higher concentrations, the positive effect decreased; however, they were better than the reference PP.

Selective harmonics elimination (SHE) is a widely applied control strategy in multilvel inverters for harmonics reduction. SHE is designed for the elimination of low-order harmonics while keeping the fundamental component equal to any previously specified amplitude. This paper proposes a novel bio-inspired metaheuristic optimization algorithm called Black Widow Optimization Algorithm (BWOA) for solving the SHE set of equations. BWOA mimics the spiders’ different movement strategies for courtship-mating, guaranteeing the exploration and exploitation of the search space. The optimization results show the reliability of BWOA compared to the state-of-the-art metaheuristic algorithms and show competitive results as a microalgorithm, opening its future application for an on-line optimization calculation in low requirement hardware.

This paper proposes a new meta-heuristic called Jumping Spider Optimization Algorithm (JSOA), inspired by Arachnida Salticidae hunting habits. The proposed algorithm mimics the behavior of spiders in nature and mathematically models its hunting strategies: search, persecution, and jumping skills to get the prey. These strategies provide a fine balance between exploitation and exploration over the solution search space and solve global optimization problems. JSOA is tested with 20 well-known testbench mathematical problems taken from the literature. Further studies include the tuning of a Proportional-Integral-Derivative (PID) controller, the Selective harmonic elimination problem, and a few real-world single objective bound-constrained numerical optimization problems taken from CEC 2020. Additionally, the JSOA’s performance is tested against several well-known bio-inspired algorithms taken from the literature. The statistical results show that the proposed algorithm outperforms recent literature algorithms and is capable to solve challenging real-world problems with unknown search space.

The kinetic study of free radical polymerization of styrene in the presence of n -pentane is a challenging and relevant topic because of its commercial and scientific value. Although this reaction has been carried out for decades, its kinetics are not fully understood. Thus, this polymerization is a current research topic mainly focused on the diffusive effects and ways to make more economical and efficient processes. This work presents a study focused on analyzing the kinetic effect of n -pentane addition during the bulk free-radical polymerization of styrene to contribute to the comprehension of phenomena which take place during this reaction. To reach this goal, we extended and implemented a model previously developed by one of the authors to perform the simulation and prediction of experimental data reported in the literature at different reaction conditions and multiple n -pentane amounts. Results obtained with the model allow us to explain the polymerization evolution in terms of the diffusive effects and the explicit theoretical description of the repetitive units that a terminal segment from a long radical involved in the termination stage can move ( U segm ). That lets us identify the effects produced by the presence of n -pentane in the theoretical transition region from chemical to diffusive control in the termination reaction. This region is relevant due to its relationship with the increasing polymerization rate and the onset of the auto-acceleration effect. The comparison of the theoretical evolution of the weight-average molecular weight ( M w ) against experimental data indicates that to enhance their correlation is necessary to consider not only the solvation effect but also the transfer effect produced by the presence of n -pentane during the polymerization.

Currently, acne in adolescents and adults is caused by an infection in follicles caused by hormonal changes, stress, water pollution, air, and earth; the last one comes into contact with the skin through the hands of patients. This project presents the incorporation of acetylsalicylic acid (ASA) to the hydroxyethylcellulose/polyacrylamide gel (HEC/PAAm) in the synthesis of gel or by its swelling. The results show us that the incorporation of ASA is possible by both methods; first, the incorporation by synthesis of degradation of the gel is more visible. The infrared spectroscopic analysis shows the functional groups of gel and ASA, 2921 and 2863 cm−1, whose assignments correspond to CH3 and CH2 groups, which are part of both the polymer and the ASA molecule, which confirms the interaction between the two groups. The microscopy photographs (SEM) show on the surface the drug in irregular whitish orthorhombic forms due to swelling; arborescent structures are observed in the case of the incorporation of the ASA drug by synthesis. Swelling kinetics has a Fickian form. The Higuchi model conforms to the release of ASA because the level of confidence is 90%. This gel was allowed to release 0.35 mg/hour, thus allowing the patient to have a continuous form of the release, in the affected area in a short period of time.

The aim of the present study is to examine the evolution of monomer conversion during suspension free radical polymerization of methyl methacrylate (MMA) at 80 °C, both in the presence and absence of nanocellulose obtained via TEMPO oxidation. The main focus of this work is on the kinetic aspects of MMA polymerization, particularly the diffusive step of the termination reaction and its impact on polymeric radicals. Experimental conversion evolutions are tracked using gravimetry. In addition, we employed an existing mathematical model to describe the effects of nanocellulose during polymerization, using the Einstein diffusion equation, geometric considerations and an approach that accounts for termination between short and long polymeric radicals. This model explains the evolution of monomer conversion regarding the effects produced by nanocellulose during the free radical polymerization reactions, focusing on factors that affect the diffusive termination step as difficulties for the short polymeric radicals reacting with the long radicals and the decrease of the segmental mobility. Our experimental results exhibit a premature autoacceleration with the presence of nanocellulose during polymerization reactions. Based on the adjustments made to the model, the theoretical results suggest that this reaction behavior is due to the impact of nanocellulose on the termination stage, which hinders a successful termination collision between short and long polymeric radicals while decreasing the segmental mobility of long radicals. Therefore, at higher nanocellulose content, the termination coefficient is reduced further.

In the present work, we prepare Cellulose Nanofibers Films (CNFs) incorporating silver nanostructures (Ag/AgCl nanocubes) in a ratio of 1–20 wt% to the organic matrix. We found that with the increase of Ag wt%, a raise in crystalline species corresponding to Ag/AgCl was observed. The diffraction pattern in 2Ө = 44.7° planes belonging to Ag (2 0 0) shifts to 2Ө = 45.45° with planes AgCl (2 2 0), due to the increase of Ag. Furthermore, we describe that incrementation in silver concentration aid in fibers gaining a higher arrangement. Scanning Electron Microscopy (SEM) images showed cubic structures formed by smaller cubic nanostructures. Electrochemical Impedance tests determined electrical resistance of the films, obtaining values of 551 Ω cm2, 62.6 Ω cm2, 3.78 Ω cm2, 7.9 Ω cm2, and 15.8 Ω cm2 for concentrations of 1 wt%, 5 wt%, 10 wt%, 15 wt%, and 20 wt% respectively; in addition to obtaining the CPE from films, demonstrating that they possess electrical conduction and energy storage capabilities.Graphic abstract