Chemical Papers最新文献

The dust accumulation on the surfaces of photovoltaic (PV) modules greatly limits the development and promotion of solar PV power generation. In this study, extensive research is conducted on the characteristics of dust accumulation on the surface of PV modules from Wuhan and Dengkou, China, and their power generation performance. In addition, the influence of dust accumulation on PV system efficiency is investigated. The results indicate that the primary phase compositions of dust in Dengkou and Wuhan are SiO₂, Al₂O₃, CaAl₂Si₂O₄·4H₂O, CaCO₃ and CaO. The PV characteristics and degree of particle agglomeration of roof PV modules in urban cities are weaker and greater, respectively, than those of desert PV modules in arid and semiarid areas. The PV system efficiency in Wuhan and Dengkou reaches a minimum value in October and August, decreasing by 40.8% and 32.8%, respectively, in comparison with those without dust accumulation. Throughout the year, the PV system efficiency in Wuhan and Dengkou is greatest in February. The power generation decreases by 74.8% and the dust accumulation coefficient increases by 61.2%, as the density of dust accumulation varies from 4.92 to 8.51 g/m². The optical performance and PV module temperature reach their maximum values in July. Dust accumulation on the surface of PV modules can reduce their optical performance by 3.2–42.2%. The PV module temperature can be increased by a maximum of 1.1% with dust accumulation in September. PV system efficiency is greater in winter than in other seasons. These findings provide significant theoretical guidance related to solar PV module cleaning methods and power generation.

A low-cost adsorbent for Ni(II) uptake was developed using orange peel waste after pretreatment with ethanol/water at 40 °C for 6 h. Various experimental factors such as pH, adsorbent dosage, and contact time were investigated, with optimal conditions determined to be pH 5, an orange peel dose of 2.5 g/L, and a contact time of 90 min. The characterization of the adsorbent was analyzed. The linear and nonlinear isotherm and kinetic models were investigated. The Langmuir model suggested chemisorption with a 19.42 mg/g capacity, following pseudo-second-order kinetics. The thermodynamic analysis revealed that the uptake was exothermic (ΔH° < 0), feasible, and spontaneous (ΔG° < 0). Regeneration studies (NaCl, NaOH, HCl, HNO₃), interference studies (Al³⁺, Cd²⁺, Ca²⁺, Na⁺, mixed solution), and application studies with real water samples (wastewater, drainage water, tap water, bottled water) were also conducted. A possible uptake mechanism was suggested. Utilizing ethanol/water-pretreated orange peels (EOP) addresses organic biomass waste disposal and offers a cost-effective, readily available solution for heavy metal removal.

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The steroidal tetracyclic skeleton and the chalcones are considered as privileged structures in medicinal chemistry. In this endeavour, pregnenolone, which is considered as the main precursor of the all steroid hormones, was subjected to Claisen-Schmidt condensation with differently substituted benzaldehydes to synthesise 12 steroidal chalconoids or chalconoyl pregnenolones (PC-1 to PC-12) including 7 new chalconoids. The structural confirmation of the synthesised compounds was based on their IR, ¹H- and ¹³C-NMR, as well as the HRMS data. Three different in vitro antioxidant assays such as DPPH^• (2,2-diphenyl-1-picrylhydrazyl), ABTS^•+ (2,2́-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)), and FRAP (ferric reducing antioxidant power) assays were performed to evaluate the antioxidant properties of the synthesised compounds. Compound PC-3, with hydroxy substituents in the 3- and 4- positions of the benzaldehyde moiety, exhibited the highest antioxidant properties, with comparable FRAP value and radical inhibitory capability to the standards employed. The antidiabetic potential of the compounds was evaluated through the α-glucosidase inhibitory assay; in which significant α-glucosidase inhibitory potential (with over 50% inhibition of the enzyme) was demonstrated by the majority of the synthesised compounds. The compounds were tested against six different bacterial strains to ascertain their antibacterial properties. The results of the antibacterial studies, such as zone of inhibition against the selected Gram-positive and Gram-negative bacteria and their minimum inhibitory concentration values suggest that the synthesised compounds possess promising antimicrobial properties against the bacterial strains.

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This paper described the development of a practical, improved and efficient method for the multigram-scale synthesis of volasertib, an injectable bioavailable potent and selective inhibitor of PLK1. The key to this optimization was the design and development of a novel synthetic strategy, which involved the preparation of key intermediate 4-amino-N-{4-[4-(cyclopropylmethyl)piperazin-1-yl]cyclohexyl}-3-methoxybenzamide (W-5) through nitro reduction sequence and (7R)-2-chloro-7-ethyl-7,8-dihydro-8-(1-methylethyl)-6(5H)-pteridinone (W-11) through reductive cyclization and N-methylation reaction. The developed process provided 46% overall yield, which enabled us to rapidly synthesize multi-gram quantities of volasertib in 99.42% purity.

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A series of (2E)-3-[2,4-bis(2-propen-1-yloxy)phenyl]-1-phenyl]-2-propen-1-ones—chalcone derivatives with O-allyloxy groups—were synthesized in good yields and characterized by different analytical techniques. Their anticancer activity was evaluated against the A549 (lung cancer) cell line. The most active compounds of this series were the 1-(4-fluorophenyl derivative 9c (IC₅₀ = 0.48 ± 0.07 µM) and the 1-(4-octyloxy)phenyl derivative 9f (IC₅₀ = 0.04 ± 0.01 µM). Network pharmacology analysis using the SwissTarget and DisGeNet databases identified potential targets for 9c in the Non-Small Cell Lung Carcinoma (NSCLC) cell line. Protein–Protein Interaction (PPI) network analysis revealed seven hub genes: MAPK14, PTGS2, HSP90AA1, MAPK8, NOS2, SYK, and NR3C1. Gene ontology analysis highlighted diverse biological functions. KEGG pathway analysis implicated pathways in cancer and immunoregulation. Molecular docking analysis suggested a strong interaction between 9c with MAPK14 (calculated docking score of  –8.4 kcal mol^–1). Compound 9c's potent activity warrants further preclinical and clinical evaluation as a potential NSCLC therapy Based on this results, study of heterocyclic compounds with O-allyloxy groups will help to explore their impact on anticancer activity and mechanistic pathway.

A sustainable, eco-friendly, and effective adsorbent has been employed for the removal of eriochrome black T (EBT) toxic dye from the effluent. This adsorbent, derived from natural chalky limestone, underwent thorough characterization using various investigative tools, including X-ray diffraction, energy-dispersive X-ray spectroscopy, Brunauer–Emmett–Teller, field emission scanning electron microscopy, transmission electron microscopy, dynamic light scattering, zeta potential, thermogravimetric analysis (TGA), and ultraviolet–visible technique. The chalky limestone exhibited distinctive properties, achieving an efficient removal percentage and high capacity within a short timeframe. Kinetic studies were conducted to assess the reaction speed, employing both pseudo-first-order and pseudo-second-order models, yielding R² values of 0.67 and 0.62, respectively. Furthermore, thermal studies were carried out using Langmuir and Freundlich models to elucidate the interaction nature between the active sites of chalky limestone and EBT dye molecules, resulting in R² values of 0.75 and 0.91, respectively. The research findings indicated that the adsorption process achieved equilibrium in just five minutes with adsorption capacity (q_t) about 1.99 mg g⁻¹, and the chalky limestone showed the ability to be reused for up to five cycles without any decrease in removal efficiency or requiring a desorption step.

Significant concerns with corrosion might occur in terms of assurance, the natural world, and financial damage. One key piece of innovation toward preventing metallic corrosion includes the application of corrosion inhibitors. The polymer inhibitions of corrosion constitute the most promising areas for advancing of new corrosion inhibitors because they have more excellent adherence locations, higher temperature rebellion, versatility, viscosity, and superior filming capacity than smaller molecule corrosion inhibitors. The present review examines the development of natural and synthetic polymers for anti-corrosion agents. Such polymeric anti-corrosion agents work very well at inhibiting corrosion and do not need a high molecular weight. At this point, we examine the published literature on polymeric corrosion inhibitors and discuss how to improve them for use in the industry.

A molecularly imprinted polymer-based dispersive micro-solid-phase extraction method has been developed for the efficient extraction and preconcentration of histamine from tuna fish samples prior to its determination by gas chromatography–flame ionization detector. In this approach, a molecularly imprinted polymer was prepared by chemical oxidation of pyrrole using iron (III) chloride, and then, it was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy and used in the extraction procedure. The method was validated using the International Council Research Protocol, and the results showed low limits of detection (0.06 mg kg⁻¹) and quantification (0.21 mg kg⁻¹), good precision (relative standard deviation = 3.2%), linearity (r² ≥ 0.9969) and acceptable extraction recovery (98%). The method was successfully done on various tuna fish samples, and histamine was determined in them.

Helicobacter pylori is a Gram-negative bacterium that infects the human gastrointestinal mucosa and is a significant human pathogen, affecting 50% of the world’s population. Multidrug Efflux Pump mepA from the MATE family of proteins acts as a potential efflux pump target in Helicobacter pylori which exports multiple drugs outside the Helicobacter pylori and consists of 417 amino acids. This study aimed to identify potential inhibitors of the multidrug efflux pump mepA in Helicobacter pylori using in-silico approaches that employed molecular docking, drug-likeness evaluation, density functional theory [DFT], molecular dynamics (MD) simulations, and free energy calculations to analyze, the interactions between phytochemicals compounds and mepA protein. The best compounds exhibiting the highest binding affinities toward mepA were selected among all the screened phytochemical compounds from the database. Overall, this research identified three promising natural compounds Hinokiflavone (− 10.9 kcal/mol), Ipomine (− 10.7 kcal/mol), and Lupinisoflavone M (− 10.5 kcal/mol) from 30 top compounds based on binding affinity score, which demonstrated remarkable binding affinities toward mepA through molecular docking, suggesting their potential to block the efflux pump and potentiate antibiotic action with the potential to inhibit the multidrug efflux pump mepA in Helicobacter pylori. Besides, we select one complex for 3 compounds for an analysis of DFT and calculate the stability of protein and protein–ligand complex by Molecular Dynamics simulation along with this we calculate the binding free energy for the complex’s protein for selected Lupinisoflavone M complex (− 98.948 kJ/mol). The study highlights the promising capacity of the selected compounds to inhibit the mepA efflux pump, potentially paving the way for developing novel therapeutic strategies against multidrug-resistant pathogens.

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Thermophysical properties have wide applications in various fields like chemical industries, mass and heat transfer processes, design and engineering calculations of industrial plants and their evaluation in liquid mixtures gives us a better understanding of intermolecular interactions taking place therein. The binary liquid mixtures under the current study comprise a range of alkanones viz. 2-Propanone, 2-Butanone, 2-Pentanone and 2-Heptanone with aromatic amines like Aniline, N-methylaniline and Pyridine at temperatures 293.15 K to 303.15 K which have multifarious industrial applications. In the present investigation, ultrasonic velocity((u)) studies have been carried out using five approaches at three temperatures. Furthermore, surface tension((sigma )), acoustical impedance((z)) and thermoacoustical parameters along with non-linearity parameters (B/A) have been evaluated. The variations in molecular interactions are well understood through interaction parameters((chi )). The obtained results indicate that the order of interactions is Pyridine < N-methylaniline  < Aniline for a specific alkanone and 2-Propanone > 2-Butanone > 2-Pentanone > 2-Heptanone for a given amine at all three temperatures. The study of thermophysical properties have been elaborated to understand the order of the interactions between various amines and alkanones.