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Pesticides can easily enter the food chain, harming bee populations and ecosystems. Exposure of beehive products to various contaminants has been identified as one of the factors contributing to the decline in bee populations, and multiple food alerts have been reported. Despite this fact, royal jelly, a valuable bee product with nutritional and functional properties, has received less attention in this context. Pesticide residues of different chemical class can contaminate royal jelly when foraging bees collect pollen or nectar from pesticide-treated flowers, or in some cases, due to its frequent and inappropriate use in the treatment of mites in beehives. To monitor this issue and also make it more reliable, it is crucial to develop effective sample preparation methods for extracting pesticides from royal jelly for subsequent analysis. In this context, this review provides information about sample preparation methods (solid-phase extraction, solvent extraction, and QuEChERS—quick, easy, cheap, effective, rugged and safe) and analytical methods that have been validated or improved to extract and analyze pesticides, respectively, in royal jelly samples of different origins. Finally, future perspectives are discussed. With this background, we aim to provide data that can guide future research related to this topic. [ABSTRACT FROM AUTHOR]

The fabrication of nonenzymatic glucose sensors is essential because of the enhancement in the selectivity and accuracy of these sensors. In this work, we used the electrodeposition approach to prepare a CeO2-based electrode for nonenzymatic glucose detection. A CeO2 branched-like nanostructure was successfully fabricated by electrodeposition on the surface of a Au substrate electrode at room temperature. The effects of cyclic voltammetry, CH3COOH content, and scan cycle number on the formation of the CeO2 branched-like nanostructure were investigated. The fabricated electrodes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results showed that a CeO2 branched-like nanostructure could be obtained with a CH3COOH content of 1.0 mL and a scan cycle number of 100 in a solution containing 0.015 M Ce(NO3)3, 0.01 M KCl, and 0.02 M CH3COONH4 and with a scan rate of 400 mV/s. The electrochemical characteristics of the sensor were examined by chronoamperometry and cyclic voltammetry. The results showed that the sensitivity of the sensor was 37.72 μA/mM·cm2 and the limit of detection (LOD) of the sensor was 0.093 mM. The findings in this work prove that it is feasible to fabricate CeO2-based sensors for nonenzymatic glucose detection. [ABSTRACT FROM AUTHOR]

Removing antibiotics from water is critical to prevent the emergence and spread of antibiotic resistance, protect ecosystems, and maintain the effectiveness of these vital medications. The combination of ozone and electrocoagulation in wastewater treatment provides enhanced removal of contaminants, improved disinfection efficiency, and increased overall treatment effectiveness. In this work, the removal of sulfamethoxazole (SMX) from an aqueous solution using an ozone–electrocoagulation (O–EC) system was optimized and modeled. The experiments were designed according to the central composite design. The parameters, including current density, reaction time, pH, and ozone dose affecting the SMX removal efficiency of the OEC system, were optimized using a response surface methodology. The results show that the removal process was accurately predicted by the quadric model. The numerical optimization results show that the optimum conditions were a current density of 33.2 A/m2, a time of 37.8 min, pH of 8.4, and an ozone dose of 0.7 g/h. Under these conditions, the removal efficiency reached 99.65%. A three-layer artificial neural network (ANN) with logsig-purelin transfer functions was used to model the removal process. The data predicted by the ANN model matched well to the experimental data. The calculation of the relative importance showed that pH was the most influential factor, followed by current density, ozone dose, and time. The kinetics of the SMX removal process followed the first-order kinetic model with a rate constant of 0.12 (min−1). The removal mechanism involves various processes such as oxidation and reduction on the surface of electrodes, the reaction between ozone and ferrous ions, degradation of SMX molecules, formation of flocs, and adsorption of species on the flocs. The results obtained in this work indicate that the O–EC system is a potential approach for the removal of antibiotics from water. [ABSTRACT FROM AUTHOR]

The recovery of metals from discarded mobile phones has been of interest due to its environmental and economic benefits. This work presents a simple and effective approach for leaching copper (Cu) from the printed circuit boards of discarded mobile phones by combining ultrasound and ozone approaches. The X-ray diffraction (XRD) technique and Fourier-transform infrared spectroscopy (FT-IR) were used to characterize the solid phases, and inductively coupled plasma optical emission spectrometry (ICP-OES) was utilized to determine the concentration of metals in the liquid phases. The effects of several influential parameters, including ultrasound, ozone dose, HCl concentration, liquid/solid ratio, temperature, and reaction time on the leaching efficiency were investigated. The results showed that the optimal conditions for Cu leaching included an ozone dose of 700 mg/h, HCl concentration of 3.0 M, liquid/solid ratio of 8, and temperature of 333 K. Under optimal conditions, about 99% of Cu was leached after 180 min. The shrinking core model was used to analyze the kinetics of the Cu leaching process, and the results showed that the surface chemical reaction governs this process. The activation energy of the leaching reaction, calculated using Two-Point form of the Arrhenius equation, was 10.852 kJ mol−1. [ABSTRACT FROM AUTHOR]

The microwave-assisted synthesis of goethite nanoparticles has been studied. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA) and Brunauer-Emmett-Teller (BET) method. Goethite rod-like nanoparticles have been successfully synthesized in 10 min of microwave treating at 100 °C. Particle size is in the range from 30 to 60 nm in width and from 200 to 350 nm in length. BET analysis indicated that the surface area of the product is 158.31 m²g-1. The feasibility of Cr(VI) removal fromaqueous solution depends on the pH of the solution and contact time. The maximum adsorptionis reached at pH 4.0 and 540 min of contact time. The adsorption kinetics was analyzedby the pseudo-first- and second-order models and the results reveal that the adsorption process obeys the pseudo-second-order model. The adsorption data were fitted well with the Langmuir adsorption isotherm. [ABSTRACT FROM AUTHOR]

Clinoptilolite is a natural mineral with exceptional physical characteristics resulting from its special crystal structure, mainstreamed into a large zeolite group called heulandites. An overall view of the research related to the synthesis, modification and application of synthetic clinoptilolite is presented. A single phase of clinoptilolite can be hydrothermally synthesized for 1-10 days in an autoclave from various silica, alumina, and alkali sources with initial Si/Al ratio from 3.0 to 5.0 at a temperature range from 120 to 195 °C. Crystallization rate and crystallinity of clinoptilolite can be improved by seeding. The modification of clinoptilolite has received noticeable attention from the research community, since modified forms have specific properties and therefore their area of application has been broadening. This paper provides a review of the use of organic compounds such as quarter alkyl ammonium, polymer, amine and inorganic species used in the modification process, discusses the processes and mechanisms of clinoptilolite modification, and identifies research gaps and new perspectives. [ABSTRACT FROM AUTHOR]

The microwave-assisted synthesis of goethite nanoparticles has been studied. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential thermal analysis (DTA) and Brunauer-Emmett-Teller (BET) method. Goethite rod-like nanoparticles have been successfully synthesized in 10 min of microwave treating at 100 °C. Particle size is in the range from 30 to 60 nm in width and from 200 to 350 nm in length. BET analysis indicated that the surface area of the product is 158.31 m²g -1 . The feasibility of Cr(VI) removal fromaqueous solution depends on the pH of the solution and contact time. The maximum adsorptionis reached at pH 4.0 and 540 min of contact time. The adsorption kinetics was analyzedby the pseudo-first- and second-order models and the results reveal that the adsorption process obeys the pseudo-second-order model. The adsorption data were fitted well with the Langmuir adsorption isotherm., Competing Interests: The authors declare no conflict of interest.