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This investigation explores the efficacy of Zeolitic Imidazolate Framework-67 (ZIF-67), a cobalt-centric metal-organic framework, in photoelectrocatalytic hydrogen generation. A comprehensive analysis of ZIF-67's structural, morphological, and photoelectrochemical attributes is conducted using techniques such as scanning electron microscopy (SEM), x-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area analysis, and ultraviolet-visible (UV–vis) absorption spectroscopy. The photoelectrochemical performance of ZIF-67 is evaluated on various substrates, including UV-ozone treated fluorine-doped tin oxide (FTO) substrates and carbon paper. This study demonstrates enhanced photoelectrocatalytic performance from ZIF-67 through strategic substrate engineering. UV-ozone treated FTO/ZIF-67 achieves -138 µA/cm² (five times improvement vs untreated FTO), while ZIF-67/carbon black delivers -390 µA/cm² (4 times higher than literature ZIF-67/BiVO₄ composites). Comprehensive analysis (SEM, XRD, BET: 1416 m²/g, UV–vis: 2.03 eV bandgap) reveals how surface hydrophilicity and conductive additives enhance charge transfer, validated by EIS, and chronoamperometry. These findings establish substrate optimization as a powerful strategy for advancing MOF-based photoelectrocatalytic hydrogen production.

A highly efficient and amine-catalyzed method for the regioselective synthesis of mono- and di-styryl nicotinonitrile, has been developed through a one-pot reaction of 2-mercapto-3-cyano-4,6-dimethylpyridine, aromatic aldehydes under mild conditions. A series of organic bases, including piperidine, morpholine, pyrrolidine, diethyl amine, and triethylamine, were screened to optimize catalytic efficiency, along with variations in solvent and reaction time. Among the tested conditions, piperidine in ethanol under reflux provided the highest yield and operational simplicity for delivering mono-styryl nicotinonitrile, whereas pyrrolidine in methanol acts as the best conditions for synthesis of di-styryl nicotinonitrile. The optimized protocol tolerates a wide range of aromatic aldehydes bearing both electron-donating and electron-withdrawing substituents, affording the desired products in moderate to excellent yields. Moreover, the photophysical properties of some selected products were studied. This method offers a straightforward, metal-free, and atom-economical approach to access functionalized nicotinonitrile derivatives with excellent regioselectivity by alteration of the amine catalyst and solvent.

It is essential to search for sustainable alternatives to develop controlled-release systems for nutrients and pesticide-based polymers to eliminate the losses of agrochemicals caused by surface runoff. This study developed new hydrogels based on PDG and lignite to enhance their use in pesticide formulations. The hydrogels were synthesized via the free radical copolymerization and characterized using FTIR, ¹³C NMR, FESEM, XRD, and TGA techniques. The swelling ratios were 299.21, 120.34, and 90.58 g.g⁻¹ for Lt-g-SAH, Lt-PDG-g-SAH, and PDG-g-SAH, respectively. The effect of pH showed that the highest swelling occurred at pH 7.2. The Korsmeyer–Peppas, Weibull, and Higuchi models were used to investigate release of thiamethoxam in distilled water (DW). Pesticide demonstrated 34.25%, 31.64%, and 28.84% release from Lt-g-SAH, Lt-PDG-g-SAH, and PDG-g-SAH, respectively, over a time duration of 92 h. Water evaporation was reduced in the following order: Blank soil > PDG-g-SAH > Lt-PDG-g-SAH > Lt-g-SAH after 12 days. These results indicate the potential of the synthesized hydrogels as a sustainable solution to reduce environmental issues arising from the use of conventional pesticides. Overall, this work establishes PDG and Lignite grafted hydrogels as an effective tool for the development of sustainable agriculture.

In this study, the synthesis of new chromenopyrimidinebenzene sulfonate derivatives was investigated. The first step of the reaction involved using 4-hydroxy or 2-hydroxybenzaldehyde, p-toluene or benzene sulfonyl chloride, and DABCO in acetonitrile to produce 2-formylphenylbenzene (p-tolyl)sulfonate derivatives. Subsequently, these derivatives were reacted with 2-hydroxybenzaldehyde, ethyl cyanoacetate, and ammonium acetate in a deep eutectic solvent (choline chloride:urea) to synthesize chromenopyrimidine derivatives. Finally, by reacting the chromenopyrimidine derivatives with p-toluene or benzenesulfonyl chloride in DABCO in DMF at room temperature, new chromenopyrimidinebenzene sulfonate derivatives were obtained. Chromeno[2,3-d]pyrimidine 4a and its benzenesulfonate esters 5a–5e were tested against Staphylococcus aureus and Escherichia coli. Compound 4a showed strong broad-spectrum activity. Compound 5d containing p-tolyl sulfonate exhibited the highest potency against E. coli due to improved membrane permeability, while 5e was less active. Compounds 4a and 5d were identified as lead candidates for further optimization.

Zingiber rubens Roxb. is a vastly persuasive species of ginger and is an indigenous cultivar native to Northeast India, especially Meghalaya, locally known as “Sying Makhir.” To determine the amount of 6-gingerol in the methanol extract of Z. rubens collected from different locations of Meghalaya, a sensitive and precise high-performance thin-layer chromatography (HPTLC) method has been developed and validated by the International Council for Harmonization (ICH) guidelines. To achieve effective separation, thin-layer chromatography (TLC) plates precoated with silica gel 60F₂₅₄ as the stationary phase and a mobile phase comprising toluene: ethyl acetate: formic acid 8:1.5:0.5 (v/v/v) were used. 6-gingerol had a retention factor (R_F) of approximately 0.32 ± 0.02 with r² = 0.997299% ± 0.10%. The linear regression analysis data for the 6-gingerol calibration curve demonstrated a satisfactory linearity relationship. 6-Gingerol was present in all samples in comparable contents, ranging from 28.71 ± 0.05 to 31.32 ± 0.08 µg/mg. The developed method was specific and robust, making it a potentially useful method for the quality control of different plants/formulations containing 6-gingerol.

The p38 MAP kinase pathway is crucial for the control of cell proliferation, apoptosis, differentiation, and stress response; its dysregulation is closely associated with tumor growth and resistance to treatment. Consequently, inhibiting this kinase constitutes a possible therapeutic approach in cancer treatment. A series of 11 trisubstituted 5-oxo-4-(3H-pyrrole-3-carbonyl)-N-phenyl-4,5-dihydro[1,2,3]triazolo[1,5-a]quinazoline-3-carbothioamides (8a–k) was synthesized and assessed for potential p38 MAP kinase inhibition and anticancer efficacy. Various spectroscopic techniques, particularly ¹H NMR, ¹³C NMR, and mass spectrometry, were employed to establish and confirm their structures. Molecular docking analyses were conducted on the p38 MAP kinase (PDB ID: 1W7H). Compound 8 h exhibited the highest docking score of −7.9 kcal/mol. The synthesized compounds were evaluated for cytotoxicity against MCF-7 breast cancer cell lines, with compound 8 h demonstrating the highest potency, with the IC₅₀ value of 29.52 ± 0.19 µM. Biochemical evaluation revealed that compound 8 h demonstrated significant inhibitory activity against p38 MAP kinase (IC₅₀ = 392.83 ± 0.19 nM). The findings indicate that compound 8 h may serve as the primary contender for the development of selective p38 MAP kinase inhibitors.

A simple method for determining water content in organic compounds has been demonstrated using Proton Nuclear Magnetic Resonance (¹H-NMR) Spectroscopy. The method has been successfully applied to measure water content in a diverse range of substances, including active pharmaceutical ingredients (APIs), sugar molecules, commercial building blocks, and various solvents. Comparative analyses with Karl Fischer titration (KFT) demonstrate high consistency with this NMR approach, confirming its reliability as an adaptable alternative for water content determination in organic compounds. The current technique offers rapid execution, requires very small sample quantities, accommodates diverse substrates, and enables quantification without precise analyte measurements.

The accumulation of radionuclides in the environment is one of the primary concerns of the nuclear industry. Hence, developing solutions for the removal of radionuclides before releasing them to the environment is undoubtedly important not only for the sustainable development of green nuclear energy but also for the environment, human health, and other applications. In this direction, developing materials with high removal capacity, preferably high selectivity, cost-effectiveness, environmental compatibility, excellent radiation resistance, and good stability has received considerable attention. Phosphates are one of the promising candidates for the adsorption of Sr and U because of their excellent ion exchange capacity, cost-effectiveness, ease of availability, and radiation resistance. Vast research has been done on these phosphate materials in recent years, and a number of sorbents have been reported, indicating the importance of a comprehensive review to identify a suitable candidate for this purpose. However, a systematic and categorical review on this topic, to the best of our knowledge, is not available. Inspired by this gap, this review collates information starting from fundamentals to various advancements and strategies developed to enhance their capacity as adsorbents. The key points discussed include the effect of doping, defect engineering, and the formation of composites hence resulting changes in interlayer spacing, morphology, crystal structure, and so forth, which will further help the material to act as a good sorbent and removal agent with enhanced sorption capacity and selectivity. Further, personal insights into challenges and future opportunities are discussed in brief. We hope that this review article on phosphate and its engineering for acting as promising removal agents will guide readers in designing novel materials and strategies for improving the adsorption capacity and selectivity of the materials toward radionuclide removal.

Neonicotinoid is one of the most important insecticides family that acts on the nervous system of insects. However, the detrimental effects of neonicotinoids on non-target organisms, highlighted the urgent need for the development of novel alternatives. Herein, an AI-driven identified coumarin insecticidal lead compound from our previous study was further optimized. The target compounds A16 and A18 showed 67.8% and 62.5% insecticidal activity against Aphis craccivora at 100 mg/L, respectively. Docking binding mode analysis demonstrated that A16 and A18 cannot form the water-bridged hydrogen bond, which may explain the less desirable activity of the compounds. The electrostatic and hydrophobic potential surfaces both revealed the weaker positive electrostatic distribution and relatively poor aqueous solubility resulted in the limited insecticidal potency. In summary, this work provides valuable insights into the structure–activity relationships of coumarin-based neonicotinoids and advances the development of novel neonicotinoid insecticides.

Ceramic-based Microstrip patch antennas (MPA) are widely used in wireless communication systems to address emerging telecommunications challenges related to size, bandwidth, and transceiver system gain. This study demonstrates the use of Barium titanate ceramic substrates for microstrip patch antennas with frequencies ranging from 8.2 to 12.4 GHz (X-band). The dielectric ceramic-based substrate, with a thickness of 1.23 mm, a length of 34 mm, and a width of 17 mm, was used to simulate the microstrip patch antenna. The research focused on electromagnetic parameters such as permittivity, permeability, dielectric loss, and magnetic loss. The nanocrystalline BaTiO₃ was synthesized by high-energy planetary ball milling followed by calcination at a temperature of 1200°C and sintering 1300^°C. The XRD graph shows a single tetragonal perovskite structure with an average crystallite size of 95.63 nm. The FESEM micrograph revealed a grain size of 2.73 µm. The microstrip patch antenna operating in X-band, based on the BT ceramic, has an excellent simulation return loss of -44.48 dB (9.91 GHz) and measured return loss -34.94 dB (9.95 GHz), simulation bandwidth 361.19 MHz, and measured bandwidth 366.8 GHz, directivity of 7.13 dB, gain of 6.26 dB, and VSWR <2 using CST Microwave Studio v. 2019. The microstrip patch antenna with wideband and high-gain is suitable microwave dielectric material for 5G network technologies.