Journal of Saudi Chemical Society最新文献

The valorization of biogenic waste by hydrothermal carbonization is widely discussed in research. However, to our knowledge, no study has combined almond shells and olive pomace to synthesize a solid carbon material. The purpose of this study is to enhance the hydrochar process from AS and OP using RSM methodology and machine learning models: ANN, SVM and XG-Boost. Subsequently, a study was carried out on the removal of organic pollutants by the synthesized material. The optimum Co-HTC operating conditions obtained at 180 C, 90 min with acid catalyst corresponding to 71.51 % and 87.13 % for mass yield and carbon retention rate respectively according to RSM-CCD. The comparison between RSM-CCD and ML in terms of prediction concludes that RSM remains more efficient in terms of planning and optimization. However, ANN is more suitable for modeling and predicting mass yields and carbon retention rates. Hydrochar’s physicochemical properties were evaluated by the use of spectroscopic methods like FTIR, SEM, XRD, and CHNO. To conclude, we studied the performance of HCop in methylene blue adsorption, varying the following parameters: pH, contact time, initial dye concentration, adsorbent dose and temperature. In addition, kinetic and isothermal models were studied to describe the dominant mechanisms in the MB adsorption process. The MB maximal adsorption using HCop obtained at pH 9, with an initial dye concentration of 100 mg. L⁻¹, 40-min contact time, 0.1 g/L adsorbent dose, and a temperature between 25 and 30 °C. In conclusion, these results provide important information on the use of Co-HTC to convert biogenic wastes into high-performance carbon materials for the appropriate removal of organic pollutants. More studies are needed to use the material in other fields of application.

In this study, we presents a novel method for bolstering the photocatalytic effectiveness of crystalline titanium dioxide (TiO₂) through the integration of graphitic carbon nitride (g-C₃N₄), creating a series of TiO₂/g-C₃N₄ nanohybrids (TiCN-NHs). Leveraging an economical and scalable pyrolysis technique, we crafted different ratios of these nanohybrids (TiCN-NHs-1, TiCN-NHs-2, TiCN-NHs-3, and TiCN-NHs-4) to optimize their performance in harnessing visible light for photocatalysis. Detailed spectroscopic examinations were performed to dissect the nanohybrids’ structural and morphological nuances, alongside their chemical interactions and states. The primary evaluation of these nanohybrids’ photocatalytic prowess was the degradation of a selected colored organic contaminant under visible light exposure. The TiCN-NHs showcased an unprecedented photocatalytic degradation efficiency, surpassing that of p-TiO₂ and bulk b-g-C₃N₄ by twelvefold and eightfold, respectively, under comparable conditions. This dramatic increase in photocatalytic activity is credited to the harmonious interface between TiO₂ and g-C₃N₄ within the nanohybrids, fostering a diminished bandgap and promoting efficient charge separation. Additionally, photoluminescence and density of state analyses, specifically focusing on valence band spectra under visible light irradiation, further confirmed these findings. The synergistic effects observed in TiCN-NHs not only enhance photocatalytic degradation rates but also spotlight the potential of these nanohybrids in solar energy conversion and environmental cleanup applications, offering a promising avenue for future research in sustainable technologies.

Hippuric acid is a biotransformation product in humans which is excreted through urine. Dietary intake of phenolic compounds increases its concentration in urine. Hippuric acid is experimentally proved to be a regulator of calcium oxalate super saturation in human urine and has a solvent effect on oxalate salts. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used analgesics employed in associated renal colic of urolithiasis. The objective of the present study was to chemically link hippuric acid through anhydride linkage to various NSAIDs to synthesize potential mutual prodrugs for urolithiasis and associated renal colic. Hippuric acid was linked to eleven NSAIDs through anhydride linkage by first synthesizing hippuryl chloride using oxalyl chloride as chlorinating agent, followed by its reaction with sodium salts of NSAIDs. Structures of obtained compounds were elucidated using UV spectrophotometry, FTIR spectrometry, 1H NMR and C-13 NMR spectrometry. Synthesized compounds were evaluated for in vitro antioxidant, in vivo acute toxicity, in vivo antiurolithic, in vivo analgesic and in vitro hydrolysis studies. Molecular docking analysis on TNF-α and COX-2 was carried out to determine target protein binding. Synthesized compounds showed stability at acidic pH which indicate potential gastro protective effect of synthesized conjugates. Compounds P9 an P6 showed maximum in vivo antiurolithic activity while P9 and P8 showed maximum in vitro antioxidant activity. All the conjugates except P2 showed significant analgesic activity which show that conjugation of hippuric acid to NSAIDs did not result in loss of analgesic potential. Docking studies showed better affinity with TNF-α as compared to COX-2.

This works documents a new silica gel-supported nanocatalyst (Si@NSBPdNPs 3) with low Pd loadings for n-alkylation reactions at room temperature. Post synthesis characterisation using SEM-EDX and ICP techniques provided a quantitative assessment of palladium species. Additionally, TEM analysis unveiled an average palladium nanoparticle size of 5.87 ± 0.2 nm. In-depth X-ray Photoelectron Spectroscopy (XPS) analysis revealed its predominant composition as Pd(0) complexed to a Schiff base ligand on low cost silica matrix. The nanocatalyst exhibited high efficacy in the catalysis of n-alkylation (Michael addition) reactions with various α,β-unsaturated Michael acceptors, yielding the corresponding n-alkyl products at room temperature with exceptional yields. Notably, the catalyst exhibited good stability and could be easily separated from the reaction mixture. Moreover, the catalyst displayed recyclability potential, maintaining its original catalytic efficacy for up to seven cycles without any discernible loss.

The escalating issue of infectious agents developing resistance to traditional antibiotics has spurred ongoing research into effective and broad-spectrum antimicrobial solutions. This study focuses on the fabrication of silver-zinc oxide Nanohybrids (A-ZnO-NHs) with varying silver content (1 %, 3 %, 5 %) using a simplified modified sol–gel method, further enhanced by a green synthesis approach utilizing orange peel extract for the generation of silver nanoparticles. The physicochemical characteristics of the A-ZnO-NCs were thoroughly examined. X-ray diffraction analysis verified the presence of Ag nanoparticles within the zinc oxide and scanning electron microscopy revealed the nanoscale silver particles uniformly distributed on the spherical zinc oxide nanoparticles. Transmission electron microscopy indicated that the Ag-ZnO-NCHs ranged in size from 10 to 20 nm. X-ray photoelectron spectroscopy analysis confirmed the formation of strong chemical bonds between the silver and zinc oxide surfaces in the nanohybrids. This study explored into the structural, morphological, and antimicrobial characteristics of the A-ZnO-NHs at different compositions. The bactericidal efficiency of the A-ZnO-NHs was assessed against both gram-positive and gram-negative bacterial strains. The impact of the A-ZnO-NHs on the cellular structure and chemical composition of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was also explored. The findings revealed that the A-ZnO-NHs with 3 % silver content demonstrated higher antimicrobial activity against E. coli and S. aureus compared to other compositions and pure zinc oxide nanoparticles. The antimicrobial activity decreases when the concentration of silver increases because the silver particles agglomerate together, reducing their surface area and lessening their effectiveness as antibacterial agents, despite their potential for various applications.

To accurately diagnose and evaluate the degree of myocardial injury and predict myocardial infarction disease, the rapid and sensitive detection of cardiac troponin I (cTnI) is required. Therefore, a label-less electrochemical aptasensor was prepared for cTnI determination. Ionic liquid 1-hydroxyethy l-3- methyl imidazole four fluorine boric acid salt (IL)-reduced graphene oxide − four ethylene oxidation reduction five amine (rGO-TEPA)/silica (SiO₂)- gold platinum (AuPt) (IL-rGO-TEPA/SiO₂-AuPt) nanocomposites were synthetized as the substrate nanocomposite and were characterized using a series of characterization methods. The performance of the prepared aptasensor was characterized through electrochemical methods. Result displayed that better substrate materials were synthesized, and the prepared electrochemical aptasensor showed excellent electrochemical performance. Under optimal conditions, the electrochemical aptasensor had a salient analytical performance. The electrochemical signals linearly decreased with the logarithm of the cTnI concentration between the 0.5 pg·mL⁻¹ and 1 × 10⁶ pg·mL⁻¹ concentration range (R² value = 0.9955) and the aptasensor had a wide detection range (0.5 ∼ 1 × 10⁶ pg·mL⁻¹) and a low detection limit of 0.4 pg·mL⁻¹. At the same time, the aptasensor had good selectivity, repeatability and stability. Relative standard deviation (RSD) values ranged from 3.45 % ∼ 4.97 % and the recovery rate was 97.5 % ∼ 103 % in human serum samples, the RSD values of the spiked recovery and ELISA method were less than 5 %. This study provides a new theoretical basis and method for the clinical detection of cTnI.

A facile, transition-metal-free, HFIP-promoted method for the synthesis of triarylmethanes through direct Friedel-Crafts reactions of imidazo[1,2-a]pyridines with chlorohydrocarbon derivatives has been described, which allows for efficient synthesis of triarylmethanes containing imidazo[1,2-a]pyridines in good to satisfactory yields at room temperature. This transformation features simple operation, excellent functional group tolerance, and a broad substrate scope.

Assembly of AgS^tBu and PhCOOH ligands with the assistance of soluble silver salt CH₃COOAg/CF₃SO₃Ag in methanol, N, N-dimethylformamide (DMF) and dichloromethane solution, yielded two Ag₂₀ cage isomers co-constructed by thiol and carboxylate/sulfonate ligands encapsulating a CO₃^2– anion template, [(CO₃^2–)@Ag₂₀(S^tBu)₁₀(PhCOO)₄(CH₃COO)₄(DMF)₄] (1) and [(CO₃^2–)@Ag₂₀(S^tBu)₁₀(PhCOO)₆(CF₃SO₃)₂(DMF)₄]·2DMF (2). The CO₃^2– anion template was generated in situ by fixing atmospheric CO₂. The precise structures of 1 and 2 were confirmed by single-crystal X-ray diffractometry (SCXRD). The thermal stability of compounds 1 and 2 was proved by thermogravimetric (TG) analysis, and their solution stability was characterized by nuclear magnetic resonance hydrogen spectroscopy (¹H NMR). The absorption spectra, photocurrent responses, and luminescence of compounds 1 and 2 were investigated. In addition, the photodegradation of methylene blue (MB) and cyclic voltammetry characteristic curves of 1 and 2 were also studied.

Due to its adjustable pore structure, the metal–organic frameworks (MOFs) have attracted much attention in the treatment of organic dye molecules in wastewater. However, the general tuning of the pore channels of MOFs is mainly by changing the chain length of the organic ligands and metal nodes. This approach not only limits the types of MOFs, but also limits the treatment of a large number of dye methylene blue (MB) and methyl orange (MO) dye molecules in the wastewater. Hence, we synthesized photoresponsive Zn-AzDC/TPA MOF as adsorbents to adsorb and release organic dye molecules in a photo-controlled manner. The photoresponsive Zn-AzDC/TPA was prepared using a mixed ligand strategy, in which the azobenzene carboxylic acid derivative (AzDC) served as a photoresponsive ligand and terephthalic acid (TPA) served as a non-active ligand in coordination with zinc ion. The optical and structural properties of the synthesized Zn-AzDC/TPA was characterized by UV–vis, FT-IR, PXRD, SEM, TEM, TGA, and pore analysis. Interestingly, it was found that the photoresponsive AzDC unit of Zn-AzDC/TPA demonstrated reversible trans–cis isomerization under the alternating UV and visible light, resulting in reversible changes in the pore size of the Zn-AzDC/TPA. Its photoresponse properties can trapp and release dye molecules under light-driven conditions. This result provides a new direction for the application of photoresponsive MOF and also lays a foundation for the study of diversified optically responsive materials.

Ammonium salt vanadium precipitation process has excellent performance in industrial production, but its shortcomings such as high cost and environmental impact are not conducive to sustainable development. In this paper, ethylenediamine was selected as the precipitant, and vanadate was precipitated from acidic simulated vanadium-rich solutions by the ammonium salt precipitation process. The high purity V₂O₅ product was obtained after calcination. Under optimal conditions, the precipitation rate of vanadium reached 94.8 %, and the purity of vanadium was as high as 99.1 %. The vanadium precipitation product was hexamethyl ammonium, and the vanadium product was V₂O₅. It can be derived by the differential method that the reaction order was n = 2.4, the reaction rate equation was $C_V^{-1.4}=kt+a$, and the apparent activation energy was 27.8097 kJ/mol, which can be classified as the diffusion-controlled reaction. This innovative process enables a savings of 5050 yuan per ton of V₂O₅. On this basis, a complete V₂O₅ production process with zero waste discharge was designed.