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In this article, silicotungstic acid (STA)-loaded metal–organic framework (MOF)-derived composites (C-STA@ZrO2) were successfully synthesized by simple strategies. X-ray diffraction, Fourier transform infrared, scanning electron microscopy, energy-dispersive X-ray, N2 physisorption, UV-vis diffuse reflection spectroscopy, and X-ray photoelectron spectroscopy techniques were used to characterize the as-obtained composites. Intriguingly, C-STA@ZrO2 exhibits excellent photocatalytic performance, and rhodamine B (RhB) (40 mg·L−1) in water can be degraded to 93.9% after 120 min of irradiation. Moreover, various catalysts, catalyst dosage, and dye concentrations on RhB degradation were evaluated. Besides, the reusability of C-STA@ZrO2 was also investigated. This work may provide a new and significant guideline for exploring excellent performance of MOF-derived hybrid material for wastewater purification.

In this article, Bi2O3@Zn-MOF hybrid nanomaterials were synthesized by supporting Zn-based metal–organic framework (Zn-MOF) through the hydrothermal method. X-ray diffractometer, Fourier transform infrared, scanning electron microscopy, energy-dispersive X-ray, N2 physisorption, X-ray photoelectron spectroscopy, and UV-Vis were used to characterize the physical and chemical properties of Bi2O3@Zn-MOF nanomaterials. The photocatalytic activity of the as-prepared hybrid has been studied over the degradation of rhodamine B (RhB). A catalytic activity of 97.2% was achieved using Bi2O3@Zn-MOF nanocomposite with the loading of 0.18 g Bi2O3, after 90 min of exposure to visible light irradiation, and the high photocatalytic performance was mainly associated with the nanorod structures, larger pore size, and broaden visible light absorption region due to the synergistic effect of the constituting materials. Furthermore, the Bi2O3@Zn-MOF nanocomposite can be reused three times and the degradation rate of RhB was maintained at 77.9%. Thus, the Bi2O3@Zn-MOF nanocomposite can act as a potential photocatalyst for the photodegradation of organic dyes in environmental applications.

In this article, Bi-based metal–organic framework-supported silicotungstic acid (STA) was synthesized by a simple hydrothermal method and used as a precursor for the preparation of the Bi-based MOF-derived catalyst (STA@C-Bi-BDC). Using a combination of FTIR, XRD, SEM-EDS, N2 adsorption–desorption, TG, UV-Vis DRS, and XPS techniques, the successful immobilization of STA groups on Bi-MOF-derived C-Bi-BDC was assessed. Furthermore, the photocatalytic performance of the as-prepared catalysts was investigated in the degradation of the RhB dye process under visible light. Within 120 min of visible light exposure, the high degradation rate of RhB (92.7%) by STA@C-Bi-BDC system was achieved, which was a lot larger than the STA (39.4%), C-Bi-BDC (59.2%), and STA@Bi-BDC (74.0%) system, and cyclic experiments exhibit that the STA@C-Bi-BDC is a relatively stable photocatalyst. More importantly, the catalyst shows high applicability for the degradation of other dyes. This study reveals a comprehensive strategy for the design of efficient Bi-based MOF-derived photocatalyst for organic dye-based wastewater treatment.

In the present study, a facile solvothermal method was used for the synthesis of silicotungstic acid (HSiW) immobilized on Ce-based metal organic framework (Ce-BDC) and embedded in Zr-based metal-organic framework (UiO-66(Zr)) composite catalyst, namely, Ce-BDC@HSiW@UiO-66 for the production of biodiesel through green fatty acid esterification. The obtained hybrids were characterized by various characterization technologies, including Fourier transform infrared, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 physisorption, X-ray photoelectron spectroscopy, and temperature-programmed desorption of NH3 (NH3-TPD) analysis. The characterization analyses showed that the hybrids have been successfully synthesized. Also, the volume and pore size of UiO-66(Zr) were changed by introducing HSiW@Ce-BDC, and the resulting Ce-BDC@HSiW@UiO-66 possessed the mesoporous structure and relatively high surface area. Simultaneously, the NH3-TPD analysis of Ce-BDC@HSiW@UiO-66 reveals that the acid strength was increased in comparison with HSiW@Ce-BDC. In addition, the composite Ce-BDC@HSiW@UiO-66 demonstrated high catalytic activity, and the oleic acid esterification gave 81.5% conversion at optimum conditions of 0.2 g catalysts, 1:30 oleic acid to methanol molar ratio at 130°C for 4 h. More interestingly, after six recycling cycles, the reduction in the conversion rate was only 4.6%, indicating that Ce-BDC@HSiW@UiO-66 has excellent reusability. Our study provides an effective approach to synthesize multifunctional hybrids for green biofuel production.

For nearly a century, the excessive discharge of organic contaminants has gradually polluted water and endangered people's health, and photocatalysis has been prominently employed to remove persistent recalcitrant organic. Here, MIL‐101(Cr) was firstly employed to introduce thin‐layered Bi2O2CO3 for the formation of Bi2O2CO3/MIL‐101(Cr) nanosheet composite, by a simple and low‐temperature in‐situ growth approach. The phase, morphology, optical, and surface characteristics of the fabricated composite were characterized through XRD, FTIR, SEM‐EDS, N2 adsorption–desorption, UV–Vis DRS, PL, TG, and XPS techniques, and the ability in the photocatalytic breakdown of rhodamine B (RhB) molecule under visible light was also studied. The results of characterization analysis and optical analysis exhibited that Bi2O2CO3/MIL‐101(Cr) has large pore size, good visible light response‐ability, and the heterojunction created by intercalating Bi2O2CO3 on MIL‐101(Cr). Photocatalytic studies revealed that Bi2O2CO3/MIL‐101(Cr) had superior RhB degradation activity than pure MIL‐101(Cr) and Bi2O2CO3, which achieved 97.1% with visible light irradiation for 20 mg/l RhB. Meanwhile, the Bi2O2CO3/MIL‐101(Cr) composite displayed good recyclability after three cycles as revealed by XRD and FTIR analysis proving their excellent stability. This study provides feasible insight into developing novel and efficient MIL‐101‐based heterojunction catalysts for environmental remediation in the future. [ABSTRACT FROM AUTHOR]

Adenoid hypertrophy can lead to adenoidal mouth breathing, which can result in “adenoid face” and, in severe cases, can even lead to respiratory tract obstruction. The Fujioka ratio method, which calculates the ratio of adenoid (A) to nasopharyngeal (N) space in an adenoidal-cephalogram (A/N), is a well-recognized and effective technique for detecting adenoid hypertrophy. However, this process is time-consuming and relies on personal experience, so a fully automated and standardized method needs to be designed. Most of the current deep learning-based methods for automatic diagnosis of adenoids are CNN-based methods, which are more sensitive to features similar to adenoids in lateral views and can affect the final localization results. In this study, we designed a local attention-based method for automatic diagnosis of adenoids, which takes AdeBlock as the basic module, fuses the spatial and channel information of adenoids through two-branch local attention computation, and combines the downsampling method without losing spatial information. Our method achieved mean squared error (MSE) 0.0023, mean radial error (MRE) 1.91, and SD (standard deviation) 7.64 on the three hospital datasets, outperforming other comparative methods. [ABSTRACT FROM AUTHOR]

This study explores the innovative application of iron filings solid waste, a byproduct from mechanical workshops, as a heterogeneous catalyst in the production of biodiesel from waste cooking oil. Focusing on sustainability and waste valorization, the research presents a dual-benefit approach: addressing the environmental issue of solid waste disposal while contributing to the renewable energy sector. Particle size distribution analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), Thermal analysis (TG-DTA), and FTIR analysis were used to characterize the iron filings. The response surface methodology (RSM) was used to guide a series of experiments that were conducted to identify the optimum transesterification settings. Important factors that greatly affect the production of biodiesel are identified by the study, including catalyst loading, reaction time, methanol-to-oil ratio, reaction temperature, and stirring rate. The catalyst proved to be successful as evidenced by the 96.4% biodiesel conversion efficiency attained under ideal conditions. The iron filings catalyst's reusability was evaluated, demonstrating its potential for numerous applications without noticeably decreasing activity. This work offers a road towards more environmentally friendly and sustainable chemical processes in energy production by making a strong argument for using industrial solid waste as a catalyst in the biodiesel manufacturing process. [ABSTRACT FROM AUTHOR]

Development of an energy‐efficient and economical route is necessary for society to synthesize green biofuels. Herein, cobalt‐doped tungstophosphoric acid (Co‐HPW) is in‐situ impregnated in the Zr‐based metal–organic framework (MOF‐801) forming composite of Co‐HPW/MOF‐801. The chemical composition, morphology, and acidic sites of the Co‐HPW/MOF‐801 composite were analyzed through x‐ray diffractometer (XRD), Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy‐dispersive x‐ray spectroscopy (EDS), thermogravimetric analysis (TG), N2 physisorption, ammonia temperature‐programmed desorption (NH3‐TPD), pyridine‐adsorbed infrared spectra (Py‐FTIR), and x‐ray photoelectron spectroscopy (XPS). The catalytic performance of the as‐synthesized catalyst was explored to catalyze esterification of lauric acid (LA) with methanol. The outcomes revealed that the Co‐HPW/MOF‐801 nanocatalyst achieved a high conversion of 86.3% under the optimized reaction condition (catalyst amount of 0.15 g, temperature of 100°C, time of 4 h, and methanol/LA molar ratio of 20:1). The excellent catalytical performance is mainly due to the large BET surface area, exposure of more active centers from available pore structure, and simultaneous possession of high Lewis and Brønsted acidity. Furthermore, the kinetic study revealed that the reaction process was kinetically controlled and the activation energy was found to be 42.1 kJ/mol. The results suggest that the synthesized Co‐HPW/MOF‐801 nanocatalyst is an environmental greenness, low cost, and suitable for easy scale‐up for the production of biofuels. [ABSTRACT FROM AUTHOR]

This study presents a novel method for synthesizing 1,4-disubstituted 1,2,3-triazole derivatives through a one-pot, multi-component addition reaction using flower-like Cu2O microbeads as a catalyst. The flower-like Cu2O microbeads were synthesized using an aqueous extract of Artimisia Campestris L. This extract demonstrated the capability to reduce and stabilize Cu2O particles during their initial formation, resulting in the formation of a porous flower-like morphology. These Cu2O microbeads exhibit distinctive features, including a cubic close-packed (ccp) crystal structure with an average crystallite size of 22.8 nm, bandgap energy of 2.7 eV and a particle size of 6 μm. Their catalytic activity in synthesizing 1,4-disubstituted 1,2,3-triazole derivatives was investigated through systematic exploration of key parameters such as catalyst quantity (1, 5,10,15, 20, and 30 mg/mL), solvent type (dimethylformamide/H2O, ethanol/H2O, dichloromethane/H2O, chloroform, acetone, and dimethyl sulfoxide), and catalyst reusability (four cycles). The Cu2O microbeads significantly increased the product yield from 20% to 85.3%. The green synthesis and outstanding catalytic attributes make these flower-like Cu2O microbeads promising, efficient, and recyclable catalysts for sustainable and effective chemical transformations. [ABSTRACT FROM AUTHOR]

To develop a post-laparoscopic anti-adhesion film with high biosafety, excellent mechanical properties and good anti-adhesion effect, chitosan (CS) and polycaprolactone (PCL) were blended with different mass ratios by electrospinning technology. The apparent morphology, mechanical properties, wettability and anti-adhesion of the obtained fiber membranes were tested and analyzed. The results show that with the increase of CS mass fraction, the spinnability decreases greatly. When CS mass fraction exceeds 40%, the fiber uniformity becomes worse. The crystallinity of the blended fiber membranes first increases and then decreases, the tensile strength, elastic modulus and bending stiffness increase, and the elongation at break decreases. Compared with pure PCL electrospun membrane, the wettability of the blended sample is significantly improved, the adhesion to fibroblasts is weakened, and the anti-adhesion effect is excellent. Considered the raw material cost, spinnability, mechanical properties and anti-adhesion effect, the blended fiber membrane with 30% CS mass fraction has the most potential application value in the field of anti-adhesion after laparoscopic surgery. [ABSTRACT FROM AUTHOR]