Explore the vast range of titles available.

Detection of nitro pollutants is an important topic in environmental protection. A total of 3 Cd (II) complexes (1–3) based on 3 soft organic isomers, n-(3,5-dicarboxylato benzyloxy) benzoic acid (n = 2, 3 or 4-H[sub.3]DBB), and a linear N-donor ligand, 3-bis(imidazole-l-ylmethyl) benzene (3-bibz), have been synthesized hydrothermally. Structural diversity of Complexes 1–3 displays the architectural 2D or 3D change: Complex 1 exhibits a 2D network featuring tri-nuclear metal units, Complex 2 is a 3D framework based on similar tri-nuclear metal units, and Complex 3 shows a 3D network with binuclear units. Fluorescent sensing properties exhibited in all these complexes have been discovered to detect nitrobenzene (NB) selectively and sensitively. In particular, Complex 3 possesses high sensitivity for NB with the lowest detection limit of 1.15 × 10[sup.−10] M. The results of the theoretical calculation verified the fluorescence detection mechanism of NB by these Cd-based complexes. Therefore, these Cd-based complexes might be used as excellent luminescent sensors for NB.

Based on quinazoline, quinoxaline, and nitrobenzene scaffolds and on pharmacophoric features of VEGFR-2 inhibitors, 17 novel compounds were designed and synthesised. VEGFR-2 IC 50 values ranged from 60.00 to 123.85 nM for the new derivatives compared to 54.00 nM for sorafenib. Compounds 15 a , 15 b , and 15 d showed IC 50 from 17.39 to 47.10 µM against human cancer cell lines; hepatocellular carcinoma (HepG2), prostate cancer (PC3), and breast cancer (MCF-7). Meanwhile, the first in terms of VEGFR-2 inhibition was compound 15 d which came second with regard to antitumor assay with IC 50 = 24.10, 40.90, and 33.40 µM against aforementioned cell lines, respectively. Furthermore, Compound 15 d increased apoptosis rate of HepG2 from 1.20 to 12.46% as it significantly increased levels of Caspase-3, BAX, and P53 from 49.6274, 40.62, and 42.84 to 561.427, 395.04, and 415.027 pg/mL, respectively. Moreover, 15 d showed IC 50 of 253 and 381 nM against HER2 and FGFR, respectively.

● A novel 3D electro-Fenton method was developed to treat nitrobenzene wastewater. ● Electrochemical oxidation combined with Fenton improves degradation efficiency. ● The new method is cost-effective and produces less sludge than conventional Fenton. Traditional Fenton oxidation is an effective method for reducing pollutants that are difficult to degrade. Owing to the large amounts of Fe(II), acids, and alkalis added in the reaction, large amounts of Fenton sludge are produced, increasing treatment costs and restricting the method's application. In this study, we developed a three-dimensional electro-Fenton system by adding iron-carbon filler and investigated the effects of different electrolytic cell structure arrangements, particle electrode dosages, sponge iron (SI) to granular activated carbon (GAC) dosage ratios, current densities, H 2O 2 dosages, and cathodic aeration on nitrobenzene (NB) wastewater treatment. The optimal system conditions were a particle electrode dosage of 100 g/L, SI:GAC mass ratio of 3:1, current density of 30 mA/cm 2, H 2O 2 dosage of 50 mmol/L, cathodic aeration of 0.8 L/min, and hydraulic retention time of 120 min. The average NB removal rate and chemical oxygen demand reached 67.38%±1.05% and 70.60%±1.15%, respectively, for which the increase in Fenton sludge was 891.8 mg/L. Different from the traditional Fenton process, additional Fe(II) was not required in the process used herein, reducing iron sludge accumulation and lowering the operating costs of using Fenton sludge as a hazardous waste treatment. In addition, the process applied in this study was able to reduce the chemical amounts used and increase the treatment efficiency. The reductions in sludge treatment costs and secondary pollutants make the proposed process an efficient and sustainable alternative for treating NB wastewater.

Thermal modification is an environmentally friendly process that does not utilize chemical agents to enhance the stability and durability of wood. The use of thermally modified wood results in a significantly extended lifespan compared with untreated wood, with minimal maintenance requirements, thereby reducing the carbon footprint. This study examines the impact of varying modification temperatures (160, 180, and 210 °C) on the lignin of spruce wood using the ThermoWood process and following the accelerated aging of thermally modified wood. Wet chemistry methods, including nitrobenzene oxidation (NBO), size exclusion chromatography (SEC), thermogravimetry (TG), differential thermogravimetry (DTG), and Fourier transform infrared spectroscopy (FTIR), were employed to investigate the alterations in lignin. At lower modification temperatures, the predominant reaction is the degradation of lignin, which results in a reduction in the molecular weight and an enhanced yield of NBO (vanillin and vanillic acid) products. At elevated temperatures, condensation and repolymerization reactions become the dominant processes, increasing these traits. The lignin content of aged wood is higher than that of thermally modified wood, which has a lower molecular weight and a lower decomposition temperature. The results demonstrate that lignin isolated from thermally modified wood at the end of its life cycle is a promising feedstock for carbon-based materials and the production of a variety of aromatic monomers, including phenols, aromatic aldehydes and acids, and benzene derivatives.

Au nanoparticles (NPs) have been found to be excellent glucose oxidase mimics, while the catalytic processes have rarely been studied. Here, we reveal that the process of glucose oxidation catalyzed by Au NPs is as the same as that of natural glucose oxidase, namely, a two-step reaction including the dehydrogenation of glucose and the subsequent reduction of O 2 to H 2 O 2 by two electrons. Pt, Pd, Ru, Rh, and Ir NPs can also catalyze the dehydrogenation of glucose, except that O 2 is preferably reduced to H 2 O. By the electron transfer feature of noble metal NPs, we overcame the limitation that H 2 O 2 must be produced in the traditional two-step glucose assay and realize the rapid colorimetric detections of glucose. Inspired by the electron transport pathway in the catalytic process of natural enzymes, noble metal NPs have also been found to mimic various enzymatic electron transfer reactions including cytochrome c, coenzymes as well as nitrobenzene reductions. Gold nanoparticles (Au NPs) with enzyme-like activities are useful glucose oxidase mimics, but the insights into the mechanism of this reaction are limited. Here, the authors show that the process of glucose oxidation by Au NPs is analogous to the one catalysed by glucose oxidase, involving dehydrogenation and oxygen reduction to H 2 O 2 ; and that other noble metal NPs also catalyse glucose dehydrogenation, but oxygen is preferably reduced to water.

Nickel nanoparticle-decorated phosphorous-doped graphitic carbon nitride (Ni@g-PC3N4) was synthesized and used as an efficient photoactive catalyst for the reduction of various nitrobenzenes under visible light irradiation. Hydrazine monohydrate was used as the source of protons and electrons for the intended reaction. The developed photocatalyst was found to be highly active and afforded excellent product yields under mild experimental conditions. In addition, the photocatalyst could easily be recovered and reused for several runs without any detectable leaching during the reaction.

Atomically monodispersed heterogeneous catalysts with uniform active sites and high atom utilization efficiency are ideal heterogeneous catalytic materials. Designing such type of catalysts, however, remains a formidable challenge. Herein, using a wet-chemical method, we successfully achieved a mesoporous graphitic carbon nitride (mpg-C 3 N 4 ) supported dual-atom Pt 2 catalyst, which exhibited excellent catalytic performance for the highly selective hydrogenation of nitrobenzene to aniline. The conversion of ˃99% is significantly superior to the corresponding values of mpg-C 3 N 4 -supported single Pt atoms and ultra-small Pt nanoparticles (~2 nm). First-principles calculations revealed that the excellent and unique catalytic performance of the Pt 2 species originates from the facile H 2 dissociation induced by the diatomic characteristics of Pt and the easy desorption of the aniline product. The produced Pt 2 /mpg-C 3 N 4 samples are versatile and can be applied in catalyzing other important reactions, such as the selective hydrogenation of benzaldehyde and the epoxidation of styrene. Designing atomically monodispersed heterogeneous catalysts with uniform active sites and high atom utilization efficiency is of fundamental and practical interest. Here, the authors report a Pt2/mpg-C3N4 catalyst showing enhanced catalytic performance toward the selective hydrogenation and epoxidation

Transition metal single atom catalysts (SACs) with M 1 -N x coordination configuration have shown outstanding activity and selectivity for hydrogenation of nitroarenes. Modulating the atomic coordination structure has emerged as a promising strategy to further improve the catalytic performance. Herein, we report an atomic Co 1 /NPC catalyst with unsymmetrical single Co 1 -N 3 P 1 sites that displays unprecedentedly high activity and chemoselectivity for hydrogenation of functionalized nitroarenes. Compared to the most popular Co 1 -N 4 coordination, the electron density of Co atom in Co 1 -N 3 P 1 is increased, which is more favorable for H 2 dissociation as verified by kinetic isotope effect and density functional theory calculation results. In nitrobenzene hydrogenation reaction, the as-synthesized Co 1 -N 3 P 1 SAC exhibits a turnover frequency of 6560 h −1 , which is 60-fold higher than that of Co 1 -N 4 SAC and one order of magnitude higher than the state-of-the-art M 1 -N x -C SACs in literatures. Furthermore, Co 1 -N 3 P 1 SAC shows superior selectivity (>99%) toward many substituted nitroarenes with co-existence of other sensitive reducible groups. This work is an excellent example of relationship between catalytic performance and the coordination environment of SACs, and offers a potential practical catalyst for aromatic amine synthesis by hydrogenation of nitroarenes. Modulating the atomic coordination structure has emerged as a promising strategy to further improve catalytic performance. Here, the authors report an atomic Co1/NPC catalyst with unsymmetrical single Co1N3P1 sites that displays high activity and chemoselectivity for hydrogenation of functionalized nitroarenes.

The hydrogenation activity of noble metal, especially platinum (Pt), catalysts can be easily inhibited by the presence of a trace amount of carbon monoxide (CO) in the reaction feeds. Developing CO-resistant hydrogenation catalysts with both high activity and selectivity is of great economic interest for industry as it allows the use of cheap crude hydrogen and avoids costly product separation. Here we show that atomically dispersed Pt over α-molybdenum carbide (α-MoC) constitutes a highly CO-resistant catalyst for the chemoselective hydrogenation of nitrobenzene derivatives. The Pt1/α-MoC catalyst shows promising activity in the presence of 5,000 ppm CO, and has a strong chemospecificity towards the hydrogenation of nitro groups. With the assistance of water, high hydrogenation activity can also be achieved using CO and water as a hydrogen source, without sacrificing selectivity and stability. The weakened CO binding over the electron-deficient Pt single atom and a new reaction pathway for nitro group hydrogenation confer high CO resistivity and chemoselectivity on the catalyst.Atomically dispersed Pt on an α-MoC support exhibits high CO tolerance during selective hydrogenation of nitrobenzene and its derivatives.

Cu-doped TiO 2 (0.1, 0.25, and 0.5% Cu-TiO 2 ) photocatalyst was prepared by sol–gel method and was characterized by powder XRD, FTIR, TEM, SEM, EDX, UV–vis diffuse reflectance (DRS), photoluminescence (PL), and Raman spectroscopy. The XRD spectrum shows tetragonal anatase phase. TEM analysis indicate that the nanoparticles were spherical with sizes 12–13 nm. The degradation of NB was studied, and an optimal degradation time of 180 min led to 98.6% NB abatement of NB = 0.05 mM, pH = 4, and catalyst loading = 50 mg/100 mL, under visible light. The degradation of NB follows the pseudo-first-order kinetics. The reusability studies indicated the excellent stability of 0.25% Cu-TiO 2 .