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Nanomaterials have excellent adsorption performance due to nano-effect and have been widely used in many fields. The adsorption performance of nanomaterials depends on their adsorption thermodynamics and kinetics. Here, the thermodynamic and kinetic equations of adsorption for spherical nanoparticles are first derived in theory. The mechanisms and regularities of influences of nano-effect on thermodynamics and kinetics, using nano-CdS adsorption of methylene blue as a probe, were investigated. The results show that there are significant influences of nano-effect (i.e., interface area effect and interface tension effect) on the thermodynamics and kinetics of nanoparticle adsorption. When the particle radius is larger and beyond the nanometer scale (∼100 nm), the nano-effect can be neglected. When the radius of the nanoparticle is within 10–50 nm, the nano-effect of adsorption is mainly the interface area effect. When the radius is less than 10 nm, the influences of both the interface area effect and the interface tension effect on adsorption thermodynamics and kinetics become more significant. The theoretic equations and experimental insights in the present work could provide a significant basis and reference for improving and perfecting the adsorption theory involving nanomaterials and provide guidelines for the explanations of adsorption mechanisms as well as the selection of adsorbents. [ABSTRACT FROM AUTHOR]

Semiconductor-based photocatalysts have become increasingly used in the removal of pollutants from wastewater, especially antibiotics. A series of composite-based cuprous oxide and bismuth vanadate (Cu2O/BiVO4) composite-based photocatalysts were synthesized by using the chemical method. The structure of the Cu2O/BiVO4 composite was verified by using x-ray diffraction, scanning electron microscopy, photoluminescence, Fourier transform infrared spectroscopy, and UV–visible spectra. The degradation of methylene blue (MB) and tetracycline (TC) was investigated to check the photocatalytic activity of the Cu2O/BiVO4 composite series. The quantity of Cu2O was varied from 1% to 7% by weight to prepare the series of Cu2O/BiVO4 composites. The analysis of results verified that 5% Cu2O/BiVO4 exhibits an outstanding photocatalytic activity as compared to 1%, 3%, and 7% Cu2O/BiVO4, pure Cu2O, and pure BiVO4 under visible light irradiation. The optimum value of photocatalytic degradation achieved with 5% Cu2O/BiVO4 was 97% for MB dye and 95% for TC in 120 min, which is greater than the photocatalytic degradation of pure BiVO4 (MB 45% and TC 72%), pure Cu2O (MB 57% and TC 80%), 1% Cu2O/BiVO4 (MB 72% and TC 85%), 3% Cu2O/BiVO4 (MB 83% and TC 88%), and 7% Cu2O/BiVO4 (MB 87% and TC 91%). The stability and reusability of Cu2O/BiVO4 were also investigated. To check the major role of trapping in degradation, a trapping experiment was also performed by using three trapping agents: BQ, EDTA, and tBuOH. The results showed that Cu2O/BiVO4 exhibits an improved photocatalytic activity in the degradation of antibiotics in polluted water because the recombination rate of the electron–hole pair decreased and the surface area increased, which increased the active sites for redox reactions. Such a photocatalytic composite with high efficiency has various applications, such as energy production, environmental remediation, and water remediation. [ABSTRACT FROM AUTHOR]

A novel, rapid, and facile method for one-step sonoelectrochemical synthesis of zinc oxide nanoparticles (UEZ) was introduced in this study. The optimum operating parameters have been selected at a voltage of 7.5 V, KCl concentration of 0.5 M, and the reaction time of 60 min. The as-prepared UEZ were characterized by XRD, SEM, and HRTEM. It was found that the UEZ has a hexagonal wurtzite structure with high crystalline quality, good purity, a size range of 30–100 nm, and good photocatalytic degradation of methylene blue. This work provides a facile route for large-scale synthesizing ZnO nanoparticles via anodization. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal CrystEngComm, which focuses on the design and understanding of solid-state and crystalline materials. It includes a range of articles on various topics, such as selective recognition and reversible encapsulation of alcohol clusters, the influence of substituents on crystal structures, and the synthesis of different materials. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document also mentions approved training courses offered by the society. [Extracted from the article]

The construction of Z-scheme heterojunctions is still a challenge. Structure tailoring and energy band engineering of metal–organic frameworks (MOFs) permit the rational design and fabrication of Z-scheme MOF/graphene oxide (GO) heterojunctions to enhance photocatalytic performance. Herein, a novel Z-scheme Zn-MOF/GO heterojunction as an environmentally friendly, reusable, and highly efficient visible-light-induced photocatalyst for methylene blue (Mb) decoloration and/or Cr(VI) reduction was synthesized. The Zn-MOF/GO composite displayed much higher photodegradation performance than pure Zn-MOF. Besides, the photocatalytic performance of composites is related to the amounts of GO, and Zn-MOF/GO(15%) showed the best activity. Specifically, Zn-MOF/GO(15%) presented 92.6% Mb decoloration, 98.8% Cr(VI) reduction, and the simultaneous removal of Mb (87.9%) and Cr(VI) (99.8%) with good stability. The improved performance for Zn-MOF/GO(15%) can be due to the formation of the Z-scheme heterojunction and built-in electric field, which can not only promote the photogenerated electron–hole separation and transfer, but also broaden the spectrum of light absorption. Furthermore, the improved plausible photodegradation mechanism of Zn-MOF/GO(15%) was provided, and e−, h+ and ·OH were the primary reactive species during the photodegradation reactions. [ABSTRACT FROM AUTHOR]

The effective management of low-concentration dye pollutants is a challenging task. Among various strategies, the Fenton reaction has emerged as a powerful approach for the degradation of dyes, particularly in the presence of highly efficient catalysts. This study presents the utilization of antimony tungstate nest modified small magnetite nanospheres (Fe3O4/Sb2WO6) as a heterostructure catalyst for the photo-Fenton mineralization of low-concentration organic pollutants, exemplified by methylene blue (MB) at ppm levels. The synthesis of Fe3O4/Sb2WO6 involves the in situ co-precipitation of agglomerated Fe3O4 nanospheres on hierarchical Sb2WO6 nests. The resulting Fe3O4/Sb2WO6 catalyst exhibits exceptional catalytic efficiency, demonstrating its capability to efficiently decontaminate low-concentration MB wastewater. Kinetics analysis reveals that the photo-Fenton-like mineralization route adheres to the first-order reaction kinetic model, and approximately 100% mineralization of MB is achieved with a minimal catalyst amount of 4 mg L−1. The straightforward preparation and outstanding performance of Fe3O4/Sb2WO6 position it as a promising candidate for the removal of dye pollutants. [ABSTRACT FROM AUTHOR]

Sodium alginate, a bio-friendly and abundant precursor of biochar (BC), was employed to prepare biochar@Co catalysts (BC@Co). A series of catalysts was synthesised at different temperatures via a one-step carbothermal method with the aim of activating peroxymonosulfate (PMS) to degrade methylene blue (MB). For the BC@Co-T (T = 500–900 °C) catalysts, the degradation process of MB by PMS was consistent with the first-order reaction kinetics model, with reaction rate constants of 0.0471–0.8041 min−1. In particular, the composite prepared at 900 °C (BC@Co-9) delivered the best PMS activation performance. Using the BC@Co-9–PMS system, the effects of various factors, including the catalyst dosage, PMS concentration, and coexisting ions, on the MB degradation rate were investigated. Under the optimal conditions of 0.005 g L−1 BC@Co-9 and 0.6 mmol L−1 PMS, the degradation rate of MB reached 100% in 18 min. Quenching experiments and electron paramagnetic resonance (EPR) measurements showed that 1O2 and ˙O2− were predominantly responsible for the degradation of MB in the BC@Co-9–PMS system. This study explored the application of sodium alginate as a recycled material and provides a feasible strategy for designing and fabricating environmentally friendly and efficient catalysts for the activation of PMS to degrade organic dyestuffs. [ABSTRACT FROM AUTHOR]

This research explores the feasibility of using date seeds (DS), an agricultural waste, for the adsorption of malachite green (MG) dye from synthesized wastewater. The characterization of the DS before and after adsorption was accomplished by FTIR, SEM, BET, and EDX measurements. Batch adsorption experiments were investigated for MG dye adsorption from aqueous solution onto the DS. The effect of different parameters such as solution pH, adsorbent dose, contact time, temperature, and the initial dye concentration were studied. The optimum pH, adsorbent dose, temperature, and contact time for the dye removal were found to be 5, 0.1 g, 25 °C, and 30 min, respectively. The equilibrium studies for the data with Langmuir, Freundlich, and Temkin isotherms showed that Freundlich isotherm is the best model to describe the adsorption of MG onto the DS particles which has a heterogeneous surface. It was found that the adsorption process follows a pseudo-second-order kinetic model which revealed that the intra-particle diffusion stage is the rate-controlling stage for the process. The thermodynamic parameters ΔG, ΔS, and ΔH suggest the possibility of chemisorption and physisorption simultaneously and indicate the exothermic and spontaneous characters of the adsorption of MG dye on DS with negative values of ΔH and ΔG. This study used agriculture waste (date seeds) which is proved to be an environmentally friendly and low-cost adsorbent. The date seeds were shown to be a promising adsorbent, demonstrating high surface area and well-developed porosity. The prepared adsorbent will have a great impact on wastewater treatment technology and possible applications at a large scale. Thus, widespread and great progress in this area can be expected in the future. [ABSTRACT FROM AUTHOR]

The emulsion photopolymerization of methyl methacrylate (MMA) using red light is reported. The synthesis of poly(methyl methacrylate) (PMMA) latexes is initiated by irradiation of a new, very efficient red‐absorbing methylene blue (MB)/sodium para‐toluenesulfinate (NapTS) system in the red region (660 nm). Visible, and especially red light penetrates the dispersed medium imposed by the emulsion process better than ultra‐violet photons (UVs). However, emulsion photopolymerizations require the development of fully water‐soluble initiating systems activable by red light, which is still hugely challenging because red photons are much less energetic, therefore generally lead to less efficient photochemical processes. The influence of the surfactant concentration and the solids content is examined over particle sizes and polymerization kinetics. The polymerizations work for solids contents between 10 and 25 wt%, with narrowly distributed particles of average sizes ranging from 40 to 65 nm. Calculations of Mie scattering support the observation that at a given wavelength the larger the particles the lower the penetration. All latexes obtained are slightly blue, which are traced to the regeneration of MB when the latexes are exposed to dioxygen. The dye regeneration enables the reactivation of the photopolymerization process. [ABSTRACT FROM AUTHOR]

In this work, CuO nanoparticles (CuO-NPs) were synthesized at 400 °C using a modification of the polymer complex-Pechini method. Considering the procedure used, a mechanism was proposed to explain the formation of CuO-NPs. The synthesized nanoparticles were characterized using IR, Raman and UV–Vis spectroscopies, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicated that the sample synthesized contained CuO as the only crystalline phase, with a crystallite size between 9.17 and 14.95 nm, depending on the crystallographic direction and gap energy values of ∼4 eV and ∼5.86 eV. The CuO powder had agglomerates, in the order of microns, and primary particles smaller than 100 nm, with irregular morphology. The CuO synthetized was not stoichiometric and that it had an excess of oxygen, indicating the presence of cation vacancies and/or interstitial oxygen. The study of the capacity of CuO-NPs to remove methylene blue (MB), without irradiating the system with UV–Vis and without the presence of H 2 O 2 , showed that these promoted a percent removal of ∼39% in a basic medium (pH ∼9.7). [ABSTRACT FROM AUTHOR]

Although doping, nanostructuration, metallization, and binary/ternary oxide systems are widely used to improve the degradation kinetics in photocatalytic processes, rapid electron _ hole recombination remains one of its major limitations. On the other hand, homogeneous photo-Fenton-like processes suffer from the slow regeneration of Fe3+/Fe2+ catalysts and the formation of iron sludge at pH > 3. In this work, a new catalytic system is designed based on the coupling of nanostructured ZnO thin films photocatalysts with Fe3+/H 2 O 2 (Fenton-Like) for the degradation of methylene blue (MB) molecules under UVA irradiation, at near-neutral pH (7.5). This coupled process promotes the formation of additional reactive oxygen species and reduces the formation of sludge by accelerating the regeneration of the iron catalysts in the medium. Furthermore, it exhibits a single kinetic regime of degradation with a rate constant of 0.0049 min−1 exceeding the sum of both individual processes and allowing therefore the removal of 94 % of MB after 480 min. [ABSTRACT FROM AUTHOR]

Waste-derived polystyrene microparticles loaded with cobalt hydroxide were prepared and tested as adsorbents for water treatment. The structure of the obtained adsorbent was analyzed by FT-IR, SEM-EDX and XRD techniques. Two dyes, namely, Reactive Red 195 and Methylene Blue were used to evaluate the adsorption behavior of the adsorbent toward anionic and cationic dyes, respectively. The effects of solution pH, contact time, temperature and adsorbent dose on the adsorption process were investigated. The adsorption data were analyzed using the Langmuir and Freundlich isotherms and the pseudo-first and pseudo-second order kinetic models. The thermodynamic parameters of the adsorption process (changes in enthalpy, entropy, and Gibbs free energy) were estimated. The maximum adsorption capacities estimated using the Langmuir model were 37.20 and 32.06 mg g−1 for Reactive Red 195 and Methylene Blue, respectively. The pseudo-first-order equation provided the best description for the adsorption kinetics. The evaluated thermodynamic parameters for adsorption indicated that the process was endothermic, random, and spontaneous. These results suggest that the cobalt hydroxide-loaded polystyrene waste could serve as an effective adsorbent for the removal of dyes from water. [ABSTRACT FROM AUTHOR]

Introduction: Discussions about the optimal lymph node (LN) count and its therapeutic consequences have persisted over time. The final LN count in colorectal tissues is affected by a variety of variables (patient, tumor, operation, pathologist, immune response). Methylene blue (MB) intra-arterial injection is a simple and inexpensive procedure that can be used to enhance lymph node count. Aim: Analyze whether there is a statistically significant difference between intra-arterial methylene blue injection and conventional dissection for the quantification of lymph nodes and determine if there is a variation in the quality of lymph node acquisition. Methods and results: Between 2015 and 2022, we conducted a retrospective analysis of colon cancer specimens. Data on the tumor's features, the number of lymph nodes, the number of lymph nodes that were positive, and other factors had been collected. The number of identified lymph nodes was highly significantly improved in the study group (P < 0.05). There is not a significant statistical difference between groups regarding the metastatic lymph node harvest. The group with injection of intra-arterial methylene blue shows a significantly decreased (P < 0.05) of the of cases with less than 12 lymph nodes recovered comparing with the control group. Conclusion: Colon cancer specimens can be easily evaluated concerning lymph nodes using the methylene blue method. Therefore, we strongly advise this approach as a standard procedure in the histological evaluation of colon cancer specimens in order to maximize the identification of lymph nodes. However, the detection of metastatic lymph nodes was unaffected significantly. [ABSTRACT FROM AUTHOR]

MIL-88B, a promising Fe-based 3D porous metal–organic framework (MOF) catalyst for the Fenton reaction, requires modifications to enhance its pro-oxidant activity and enable magnetic control of the sample. This study reports the successful modification of MIL-88B with iron oxide (Fe3O4) and ascorbic acid (AA). The characterization of the crystal structure and morphology of the Fe3O4–AA MOF sample using X-ray diffraction, Raman and Mössbauer spectroscopy, and scanning electron microscopy revealed that AA facilitated the formation of magnetite with a composition approaching a stoichiometry of Fe2.96O4 while preserving the MOF structure. Specifically, in the presence of hydrogen peroxide (H2O2), Fe3O4–AA–MOF exhibited a 3-fold increase in the Fenton reaction rate for methylene blue degradation compared to the conventional homogeneous system at pH 4.5. Furthermore, Fe3O4–AA–MOF retained the antibacterial properties of AA, as evidenced by its ability to increase reactive oxygen species in luminescent marine bacterium Photobacterium phosphoreum at low concentrations while exhibiting moderate cytotoxicity. The enhanced pro-oxidant activity of the Fe3O4–AA–MOF/H2O2 system is attributed to an AA-promoted surface Fe2+/Fe3+ cycle. A possible mechanism for this system is proposed. [ABSTRACT FROM AUTHOR]

Synthesis of a novel binuclear Cu(II) carboxylate complex under ambient laboratory conditions is presented. The complex exhibits a paddle wheel structure in which the axial positions are occupied by two copper atoms instead of two water molecules. The synthesized complex was characterized by single-crystal X-ray crystallography, FT-IR, X-ray diffraction, and UV-visible spectroscopy techniques. The thermal stability of the metal complex was studied by the thermogravimetric analysis study. The synthesized metal complex was employed for the synthesis of metal complex-coated polyether sulfone (PES) membranes which were characterized before and after filtration using the FESEM technique. The photocatalytic efficiency of the metal complex was studied for the degradation of methylene blue dye under UV irradiation in the presence of H2O2 and was compared with the photodegradation efficiency of the metal complex-coated polyether sulfone (PES) membrane. [ABSTRACT FROM AUTHOR]

ABSTRACT In this review, we compare different refractory anaphylaxis (RA) management guidelines focusing on cardiovascular involvement and best practice recommendations, discuss postulated pathogenic mechanisms underlining RA and highlight knowledge gaps and research priorities. There is a paucity of data supporting existing management guidelines. Therapeutic recommendations include the need for the timely administration of appropriate doses of aggressive fluid resuscitation and intravenous (IV) adrenaline in RA. The preferred second‐line vasopressor (noradrenaline, vasopressin, metaraminol and dopamine) is unknown. Most guidelines recommend IV glucagon for patients on beta‐blockers, despite a lack of evidence. The use of methylene blue or extracorporeal life support (ECLS) is also suggested as rescue therapy. Despite recent advances in understanding the pathogenesis of anaphylaxis, the factors that lead to a lack of response to the initial adrenaline and thus RA are unclear. Genetic factors, such as deficiency in platelet activating factor‐acetyl hydrolase or hereditary alpha‐tryptasaemia, mastocytosis may modulate reaction severity or response to treatment. Further research into the underlying pathophysiology of RA may help define potential new therapeutic approaches and reduce the morbidity and mortality of anaphylaxis. [ABSTRACT FROM AUTHOR]

The recombination of photoexcited electron–hole pairs greatly limits the degradation performance of photocatalysts. Ultrasonic cavitation and internal electric field induced by the piezoelectric effect are helpful for the separation of electron–hole pairs and degradation efficiency. The activated foam carbon (AFC) owing to its high surface area is often used as the substrate to grow catalysts to provide more reactive active sites. In this work, CuO@BaTiO3 (CuO@BTO) heterostructure is prepared by hydrothermal method on the surface of AFC to investigate the ultrasonic piezoelectric catalysis effect. X-ray diffraction (XRD), Raman spectroscopy, energy dispersive x-ray spectroscopy (EDS) and scanning electron microscopy (SEM) were used to analyze the structure and morphology of CuO-BTO/AFC composite. It is found that the CuO-BTO/AFC composite exhibits excellent piezo-catalytic performance for the degradation of organics promoted by ultrasonic vibration. The CuO-BTO/AFC composite can decompose methyl orange and methylene blue with degradation efficiency as high as 93.9% and 97.6% within 25 min, respectively. The mechanism of piezoelectricity enhanced ultrasound supported catalysis effect of system CuO-BTO/AFC is discussed. The formed heterojunction structure between BTO and CuO promotes the separation of positive and negative charges caused by the piezoelectric effect. [ABSTRACT FROM AUTHOR]

Methylene blue (MB) has been shown to reduce mortality and morbidity in vasoplegic patients after cardiac surgery. Though MB is considered to be safe, extravasation of MB leading to cutaneous toxicity has been reported. In this study, we sought to characterize MB-induced cutaneous toxicity and investigate the underlying mechanisms. To induce MB-induced cutaneous toxicity, we injected 64 adult male Sprague-Dawley rates with 200 µL saline (vehicle) or 1%, 0.1%, or 0.01% MB in the plantar hind paws. Paw swelling, skin histologic changes, and heat and mechanical hyperalgesia were measured. Injection of 1%, but not 0.1% or 0.01% MB, produced significant paw swelling compared to saline. Injection of 1% MB produced heat hyperalgesia but not mechanical hyperalgesia. Pain behaviors were unchanged following injections of 0.1% or 0.01% MB. Global transcriptomic analysis by RNAseq identified 117 differentially expressed genes (111 upregulated, 6 downregulated). Ingenuity Pathway Analysis showed an increased quantity of leukocytes, increased lipids, and decreased apoptosis of myeloid cells and phagocytes with activation of IL-1β and Fos as the two major regulatory hubs. qPCR showed a 16-fold increase in IL-6 mRNA. Thus, using a novel rat model of MB-induced cutaneous toxicity, we show that infiltration of 1% MB into cutaneous tissue causes a dose-dependent pro-inflammatory response, highlighting potential roles of IL-6, IL-1β, and Fos. Thus, anesthesiologists should administer dilute MB intravenously through peripheral venous catheters. Higher concentrations of MB (1%) should be administered through a central venous catheter to minimize the risk of cutaneous toxicity. [ABSTRACT FROM AUTHOR]

It is shown that one‐electron oxidation of aniline with methylene blue is possible only at low temperatures under UV radiation. The kinetics of aniline polymerization under the action of ammonium persulfate in the presence of catalytic amounts of methylene blue is studied. Kinetic curves are obtained by electron paramagnetic resonance (EPR) spectroscopy at various temperatures and concentrations of methylene blue. The catalytic action of the unassociated form of methylene blue and the deactivation of reactive complexes by the dye dimers are shown to compete. In the context of the obtained results the autocatalysis mechanism of oxidative polymerization is considered, which suggests the formation of complexes of aniline and polyaniline that are subject to subsequent rapid oxidation by the persulfate anion. [ABSTRACT FROM AUTHOR]

The pure conjugated polyarylene azomethine (CPAA) and its nanocomposites (CPAA-TiO2) with different concentrations of TiO2 nanoparticles were successfully prepared by in-situ technique and analyzed by different advanced techniques. XRD has confirmed the structural properties and crystallinity of (CPAA) and nanocomposites. The SEM clearly shows that the (CPAA) is uniform and homogeneous, with tightly connected aggregate layers in shape. However, the amount of TiO2 in the nanocomposites greatly affects their morphology, revealing structural differences and indicating a reaction between (CPAA) and TiO2, especially at a higher concentration of 5% TiO2. A new composite of (CPAA) was introduced and the photocatalytic effect for MB was studied. The removal efficiency of (pure-CPAA) over MB dye under simulated sunlight was 62%. However, (CPAA-TiO2 1%) destroyed 90% of MB dyes. It was discovered that the low band gap of (CPAA-TiO2 1% (2.84 eV)) accelerates high electron–hole recombination, increasing photocatalytic activity. [ABSTRACT FROM AUTHOR]

In this study, a pioneering composite material, MIL‐68‐NH2@MCC, was synthesized by integrating an indium‐based metal–organic framework (MIL‐68‐NH2) with microcrystalline cellulose (MCC), that could be prepared by recycling different natural products of cellulose. The surface characteristics of the novel MIL‐68‐NH2@MCC composite were meticulously examined through X‐ray diffraction (XRD), infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy (EDX). Remarkably, MIL‐68‐ NH2@MCC demonstrated significantly improved efficiency in removing methylene blue (MB) dye and Sm(III) ions from aqueous solutions, surpassing the removal capabilities of its individual constituents, MIL‐68‐NH2 and MCC. This superior performance can be attributed to the synergistic interplay between MIL‐68‐ NH2 and MCC. We thoroughly investigated the influence of various parameters, including pH, contact time, initial concentration, and temperature. The experimental adsorption data for both MB and Sm(III) exhibited a good fit with the Langmuir isotherm model. The optimized MIL‐68‐NH2@MCC exhibited remarkable maximum adsorption capacities of 133.8 mg/g for MB and 72.1 mg/g for Sm(III). The adsorption kinetics followed a pseudo‐second‐order model with correlation coefficients of 0.9879 and 0.9875 for MB and Sm(III), respectively. The application of intraparticle diffusion and the Boyd kinetic models demonstrated that the film diffusion is the dominant factor influencing the rate of the adsorption process. The study also examined a possible mechanism for the adsorption of MB and Sm(III) on the optimized MIL‐68‐NH2@MCC surface. Ultimately, the results highlight the originality of our research in terms of the efficacy of the newly developed MIL‐68‐NH2@MCC composite as an eco‐friendly adsorbent. Besides, the developed adsorbent effectively removes MB and Sm(III) from different water solutions while exhibiting outstanding selectivity and reusability. [ABSTRACT FROM AUTHOR]

Hydrogels are of great importance for functionalizing sensors and microfluidics, and poly(ethylene glycol) dimethacrylate (PEG-DMA) is often used as a viscosifier for printable hydrogel precursor inks. In this study, 1–10 kDa PEG-DMA based hydrogels were characterized by gravimetric and electrochemical methods to investigate the diffusivity of small molecules and proteins. Swelling ratios (SRs) of 14.43–9.24, as well as mesh sizes ξ of 3.58–6.91 nm were calculated, and it was found that the SR correlates with the molar concentration of PEG-DMA in the ink (MCI) (SR = 0.1127 × MCI + 8.3256, R2 = 0.9692) and ξ correlates with the molecular weight (Mw) (ξ = 0.3382 × Mw + 3.638, R2 = 0.9451). To investigate the sensing properties, methylene blue (MB) and MB-conjugated proteins were measured on electrochemical sensors with and without hydrogel coating. It was found that on sensors with 10 kDa PEG-DMA hydrogel modification, the DPV peak currents were reduced to 92 % for MB, 73 % for MB-BSA, and 23 % for MB-IgG. To investigate the diffusion properties of MB(-conjugates) in hydrogels with 1–10 kDa PEG-DMA, diffusivity was calculated from the current equation. It was found that diffusivity increases with increasing ξ. Finally, the release of MB-BSA was detected after drying the MB-BSA-containing hydrogel, which is a promising result for the development of hydrogel-based reagent reservoirs for biosensing. [ABSTRACT FROM AUTHOR]

Biochar enriched with metals has an increased potential for sorption of organic and inorganic pollutants. The aim of the research was to identify the possibility of using biochar composites produced on the basis of waste plant biomass and waste FFH (ferryferrohydrosol) containing iron atoms, after CO2 capture. The composites were produced in a one-stage or two-stage pyrolysis process. Their selected properties were determined as follows: pH, ash content, C, H, N, O, specific surface area, microstructure and the presence of surface functional groups. The produced biochar and composites had different properties resulting from the production method and the additive used. The results of experiments on the removal of methylene blue (MB) from solutions allowed us to rank the adsorbents used according to the maximum dye removal value achieved as follows: BC1 (94.99%), B (84.61%), BC2 (84.09%), BC3 (83.23%) and BC4 (83.23%). In terms of maximum amoxicillin removal efficiency, the ranking is as follows: BC1 (55.49%), BC3 (23.51%), BC2 (18.13%), B (13.50%) and BC4 (5.98%). The maximum efficiency of diclofenac removal was demonstrated by adsorbents BC1 (98.71), BC3 (87.08%), BC4 (74.20%), B (36.70%) and BC2 (30.40%). The most effective removal of metals Zn, Pb and Cd from the solution was demonstrated by BC1 and BC3 composites. The final concentration of the tested metals after sorption using these composites was less than 1% of the initial concentration. The highest increase in biomass on prepared substrates was recorded for the BC5 composite. It was higher by 90% and 54% (for doses of 30 g and 15 g, respectively) in relation to the biomass growth in the soil without additives. The BC1 composite can be used in pollutant sorption processes. However, BC5 has great potential as a soil additive in crop yield and plant growth. [ABSTRACT FROM AUTHOR]

The continuous discharge of organic dyes into freshwater resources poses a long-term hazard to aquatic life. The advanced oxidation Fenton process is a combo of adsorption and degradation of pollutants to detoxify toxic effluents, such as anti-bacterial drugs, antibiotics, and organic dyes. In this work, an activated attapulgite clay-loaded iron-oxide (A-ATP@Fe3O4) was produced using a two-step reaction, in which attapulgite serves as an enrichment matrix and Fe3O4 functions as the active degrading component. The maximum adsorption capacity (qt) was determined by assessing the effect of temperature, pH H2O2, and adsorbent. The results showed that the A-ATP@Fe3O4 achieves the highest removal rate of 99.6% under optimum conditions: 40 °C, pH = 3, H2O2 25 mM, and 0.1 g dosage of the composite. The dye removal procedure achieved adsorption and degradation equilibrium in 120 and 30 min, respectively, by following the same processes as the advanced oxidation approach. Catalytic activity, kinetics, and specified surface characteristics suggest that A-ATP@Fe3O4 is one of the most promising candidates for advanced oxidation-enrooted removal of organic dyes. [ABSTRACT FROM AUTHOR]

Ag3PO4 is an effective green photocatalyst that exhibits higher visible light photocatalytic performance for the degradation of various organic pollutants. The photocatalytic performance of Ag3PO4 is affected by the exposed high‐energy crystal facets. Herein, Ag3PO4 with different morphologies and specific surfaces is synthesized via a direct precipitation method in the presence of triethanolamine (TEA). The Ag(TEA)n complex, which served as an intermediate medium, plays a critical role during the morphological transformation. When the molar ratio of Ag+ to TEA is set as 1:12, 18‐facet polyhedral morphology of Ag3PO4 crystals is obtained. The spherical and dodecahedral samples are also obtained by adjusting the molar ratio of Ag+ to TEA as 1:1 and 1:14. The photocatalytic activity of the samples for the degradation of methylene blue (MB) is tested under visible light irradiation. It is demonstrated when the molar ratio of Ag+/TEA is 1:12, Ag3PO4 polyhedra with 18‐facet are fabricated. X‐ray diffraction and scanning electron microscopy results indicate that the 18‐facet polyhedron, with six {100} facets and twelve {110} facets, enjoys the most exposed high‐energy crystal facets. Photocatalytic experiments show that the 18‐facet polyhedron has the best performance, and the degradation of MB by Ag3PO4 polyhedron with 18‐facet morphology reaches 90% within 70 min. [ABSTRACT FROM AUTHOR]

Background: In 2022, suicide ranked as the 11th leading cause of death in the United States with 49,513 deaths. Provisional mortality data from 2022 indicate a 2.8% increase in the number of suicides compared to 2021. This paper examines overall suicide trends, sodium nitrite ingestion as an emerging suicide method, and the role that online forums play in sharing information about suicide methods (including sodium nitrite ingestion). Methods: Suicides were identified from CDC's National Vital Statistics System (2018-July 2023 provisional) multiple cause-of-death mortality files using International Classification of Diseases (ICD), Tenth Revision underlying cause-of-death codes U03, X60–X84, and Y87.0 and T code T50.6 (antidotes and chelating agents). Google search popularity metrics were captured from January 2019 to January 2023. Case reports of sodium nitrite related suicide and suicide attempts (through February 2024) were identified in the medical and forensic literature. Results: At least 768 suicides involving antidotes and chelating agents (including sodium nitrite) occurred between 2018 and July 2023, set in the context of 268,972 total suicides during that period. Overall, suicides involving antidotes and chelating agents (including sodium nitrite) represent <1% of all suicides, however, numbers are rising. Conclusions: Suicide methods are known to change over time. These changes can be influenced by, among other factors, online forums and means accessibility, such as internet purchase availability. CDC remains committed to prevention through comprehensive public health strategies that protect individuals, families, and communities. Practical Applications: States and community partners might consider leveraging physicians, emergency responders, and other appropriate crisis response groups to disseminate information on sodium nitrite self-poisoning and its antidote, methylene blue. Efforts should be part of a comprehensive public health approach to suicide prevention. [ABSTRACT FROM AUTHOR]

Wastewater from the textile and dyeing industries contains hazardous dyes. This study aims to determine the effectiveness of magnetic biochar nanocomposites synthesized from khat leftovers (KLs) and coffee husks (CHs) in removing methylene blue (MB) from wastewater. Magnetic biochar nanocomposites were synthesized by pretreating 25 g of biomass with a 12.5 mmol mixture of FeS and FeCl3 at a 1:1 molar ratio, followed by pyrolyzing at 300°C for 1 h. The resulting products were analyzed using X‐ray diffraction, Fourier transform infrared, scanning electron microscope, and Brunauer‐Emmett‐Teller. The results showed that the adsorbents are amorphous, and the activated biochars, are more porous and contain various functional groups such as C‐O, C = C, O‐H, C‐H, and Fe‐O. When 0.2 g of pristine biochars of CH and KL were applied to 20 mL aqueous solutions containing 20 mg/L of MB at pH 7.5 and 25°C, they removed 44.73% and 75.26% of MB, respectively. However, the resulting nanocomposites exhibited a maximum removal efficiency of 99.10% and 99.23% with magnetic iron oxide‐CH biochar nanocomposite (Fe3O4‐CHBNC) and magnetic iron oxide‐KL biochar nanocomposite (Fe3O4‐KLBNC), respectively, with maximum adsorption capacities of 51.02 and 78.13 mg/g. The reusability study also showed removal efficiencies of 77.57% and 83.49% up to six‐cycle reuse. [ABSTRACT FROM AUTHOR]

Cyanosis is a bluish discoloration of the tissues due to increased levels of deoxygenated hemoglobin in capillaries. It is a common finding in newborn infants that can be caused by different diseases, including pulmonary, cardiac, infectious, and hematological disorders. Methemoglobinemia is a rare cause of cyanosis, in which hemoglobin is oxidized, changing its heme iron configuration from the ferrous (Fe2 +) to the ferric (Fe3 +) state, creating methemoglobin (Met-Hb), a form that does not bind oxygen, leading to decreased oxygen delivery to the tissues and cyanosis. We report a rare case of a preterm newborn, who developed cyanosis and worsening hypoxemia on day ten of life, she was found to have elevated Met-Hb percentage in blood gas analysis that required treatment with intravenous methylene blue. Her symptoms resolved after a period of maintenance treatment with oral methylene blue and ascorbic acid, and the etiology of her disease remains unclear. [ABSTRACT FROM AUTHOR]

Low-quality cotton fibers are a low-value waste material within the cotton industry. Upcycling and transforming into high-value materials are highly desired. This study investigates upcycling fibers into hydrogel biosorbents and assesses their efficacy in dye adsorption. An effective gelation approach was employed via simply dropping droplets of suspension mixture of sodium alginate and fibers into acidic bath. Resulting composite hydrogel beads were utilized for dye removal. Composite beads successfully immobilized less than 70 wt% of fibers and achieved a significant improvement in thermal stability. Composite beads with 50 wt% fibers and alginate showed no decrease in methylene blue adsorption capacity. This outcome was unexpected considering the lower dye adsorption capacity of fibers than alginate, particularly notable since it indicated that reduced quantities of the more costly sodium alginate were sufficient to achieve comparable dye adsorption capacity. Mechanistic study unveiled that both the loose crosslinking structure and the electrostatic forces were responsible for the unexpected high adsorption capacity of 50% fiber-alginate. This study reports a promising, innovative and effective upcycle strategy for the first time that can transform fibers into high-value biosorbents without compromising dye adsorption capability. [ABSTRACT FROM AUTHOR]

Photocatalytic processes are able to decompose dyes and toxic substances in the water environment. This fascinating topic can address many environmental concerns about polluted water. Zinc oxide is widely used as a photocatalyst in various nanocomposites. In this study, the formation of a nanostructure including cyclodextrin and ZnO has been investigated by density functional theory (DFT) in gas and aqueous phases at B3LYP and M06-2X functional levels. The calculated binding energies and natural bond orbital (NBO) analysis indicate the existence of strong chemical interactions of ZnO with the inside of the cyclodextrin (CD) cavity during CD-ZnO formation. In addition, the interaction of methylene blue (MB) and phenol red (PhR) dyes with CD-ZnO nanostructure has been investigated. The dyes' adsorption energy values on the CD-ZnO ranged from − 243.4 to − 55.9 kJ. These energies and the density of states diagrams in their complexes confirm the strong interaction of MB and PhR with CD-ZnO. This strong interaction of dyes with nanostructure can support the mechanisms that lead to the photocatalytic degradation of dye molecules. [ABSTRACT FROM AUTHOR]

In this study, magnetite (Fe3O4) material was synthesized from natural iron sand and subsequently augmented with chitosan/silver nanoparticles (Fe3O4/CS/AgNPs) to serve as a methylene blue (MB) adsorbent. The Fe3O4/CS/AgNPs composite was prepared via co-precipitation method and confirmed by X-ray diffraction (XRD), vibrating sample magnetometry (VSM), Fourier transform infrared spectroscopy (FTIR), and field emission-scanning electron microscopy (FE-SEM). FE-SEM images revealed that Fe3O4 and Fe3O4/CS/AgNPs composites were octahedron and oval-shaped, respectively, with Ag particles evenly dispersed across the Fe3O4/CS surface. The VSM data disclosed that the saturation magnetization for the Fe3O4/CS/AgNPs adsorbent was 21.36 emu/g, and it could be effortlessly separated from the solution with the help of an external magnet. The kinetics and adsorption isotherms data for MB on the Fe3O4/CS/AgNPs composite correspond well with the pseudo-second-order kinetic model and Langmuir isotherm model. The maximum adsorption capacity for MB on the Fe3O4/CS/AgNPs adsorbent was 74.63 mg/g, and the percentage removal of MB could be maintained at 70.4% after five cycles of repetition. Overall, the Fe3O4/CS/AgNPs composite shows promise as a reliable adsorbent for eliminating MB from environments. [ABSTRACT FROM AUTHOR]

Tree decline is described as the loss in tree vigor and increased mortality initiated by climate change events, and also involves pathogens and pests. Stem bleeding and bark canker of oak (Quercus castaneifolia) were observed in Mazandaran and Golestan forests during summer 2020–2021. Symptoms included cracks in the outer bark, stem tissue necrosis, bleeding, dark exudate and dark brown lesions in the inner bark. Eighty-nine strains with a metallic green sheen pigment were isolated on eosin methylene blue agar. The pathogenicity of all strains recovered in this study was assessed on oak seedlings and acorns. Forty-four strains produced rotting on oak acorns 2 weeks after inoculation. Inoculation of six representative strains on oak seedlings resulted in twig dieback of the plants after 4 weeks. Strains were negative for Gram reaction, oxidase and levan formation from sucrose. The gyrB and infB gene sequence similarity values of strains were 98.87–99.57% with the type strain of Gibbsiella quercinecans, 98.66–98.86% with the type strain of Gibbsiella greigii and 99.46–99.64% with the type strain of Dryocola boscaweniae. In the phylogenetic tree based on concatenated sequences of gyrB and infB genes or each gene individually, the strains were divided into three clusters containing the type strains of G. quercinecans, G. greigii and D. boscaweniae, each with high bootstrap support and confirming their identity as belonging to these three species. To the best of our knowledge, this is the first report of oak bacterial canker caused by D. boscaweniae, G. greigii and G. quercinecans in Iran and the first report of D. boscaweniae associated with oak decline symptoms. [ABSTRACT FROM AUTHOR]

[Display omitted] Herein, for the first time, we reported the synthesis of a novel Z-scheme Co x Ni 1−x TiO 3 /CdS (x = 0.5) heterojunction photocatalyst and the investigation of its visible-light-driven photocatalytic performance toward degradation of methylene blue (MB). The developed photocatalyst was structurally characterized by applying X-Ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), differential reflectance spectroscopy (DRS), and photoluminescence (PL) techniques. The results indicated the formation of a highly porous structure with improved visible light adsorption capacity, favorable for the catalytic activity. At an optimum condition of 10 mg/L of MB and 300 mg/L of catalyst, the ternary photocatalyst demonstrated a MB removal efficiency of 99 % after 75 min of the treatment process. The radical trapping experiments unveiled that hydroxyl and superoxide radicals were two main reactive species formed under visible light, while the valance holes possessed an insignificant role. The synergetic impact of the Co x Ni 1−x TiO 3 (x = 0.5) and CdS on the photodegradation of MB over the as-prepared Co x Ni 1−x TiO 3 /CdS (x = 0.5) photocatalyst through Z-scheme photocatalysis was indicated by the results of the mechanism studies. The percentage impact of the treatment time, MB concentration, the ratio of Co x Ni 1−x TiO 3 /CdS (x = 0.5), and the dosage of catalyst using analysis of the CCD modeling was obtained as 47.04, 16.67, 7.22 and 0.87 %, respectively. Furthermore, the as-synthesized photocatalyst possessed high recyclability and photostability with only a 3 % decline in activity after four repetitive cycles. [ABSTRACT FROM AUTHOR]

Dyes can be determined as a substance that creates many environmental issues leading to the death of aquatic life, plants and all living organisms. Dye removal can be done by several physical, chemical and biological methods, including the photocatalytic method. Photocatalysis is a method in which light energy is used to degrade the dye. This technique is low-cost and eco-friendly, and it degrades many harmful substances from organic dyes compared to other techniques. The prime aim of the present work is to degrade the largely used organic dyes such as methylene blue, malachite green and crystal violet using EDTA-doped FeZnS2 and Leishman stain-doped FeZnS2 thin films. The doped FeZnS2 thin films were fabricated using the co-precipitation method. Thin fabricated films are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and UV–Visible spectroscopy (UV). These characterization studies show an active photo response indicating effective dye degradation. Based on the absorption studies of UV spectroscopy measurements after 60 min, the degradation efficiency of methylene blue, crystal violet and malachite green using EDTA-doped FeZnS2 are 76, 85 and 90, respectively. Similarly, the degradation efficiency after 60 min of methylene blue, crystal violet and malachite green using Leishman stain-doped FeZnS2 are 82, 79 and 89, respectively. [ABSTRACT FROM AUTHOR]

Scientists have become interested in treating dye-contaminated water due to the health issues and ecological imbalances caused by the presence of these injurious compounds in water. Herein, two MnO2 polymorphs i.e. ε- and γ-MnO2 were prepared by the comproportionation reaction between KMnO4 and MnCl2. In comparison to γ-MnO2, ε-MnO2 has greater surface area, pore width, and pore volume. According to the thermal study, ε-MnO2 contains more surplus mass in the form of negatively charged surface hydroxyl groups than γ- phase. The adsorption capability of both polymorphs was examined for the removal of both cationic (methylene blue, malachite green and crystal violet) and anionic dyes (eosin yellow). The efficient adsorption for the cationic dyes using ε-MnO2 was occurred in the neutral medium, where it had a highly negative surface as determined by zeta potential measurements. It only took few minutes to complete the removal. The electrostatic interactions of the cationic dye molecules with the OH- groups account for this result. While, complete dye removal (40 min) was occurred in the acidic medium using γ-MnO2. On the other hand, in the neutral medium the adsorption of the anionic dye molecules on the surface of both MnO2 phases was hampered by the repulsion forces. As a result, despite extending the contact time to 180 min and the adsorbent dose to 50 mg, no anionic dye removal was seen. On the contrary, in the acidic medium very fast removal occurs for Eosin Y as the surface of both MnO2 phases acquired a positive charge. The influence of the ionic strength on MB elimination was investigated. The results showed that as the content of NaCl was increased, the removal effectiveness decreased from 100% to 35%. The kinetics of cationic dye adsorption on the ε-MnO2 surface was studied, and it was discovered that the mechanism follows a pseudo-second order model. [ABSTRACT FROM AUTHOR]

Herein, heavy rare‐earth substituted bismuth ferrite thin films were prepared using a low‐temperature sol–gel‐assisted spin coating method. The substitution of heavy rare‐earth ions for Bi3+ leads to structural transformation from rhombohedral (R3c) for x = 0.05 to orthorhombic (Pnma) symmetry for x = 0.05, which was found to have a great effect on the surface morphology, optical band‐gap energy, and photocatalytic activity of a BiFeO3(BFO) thin film. Moreover, the optical properties of prepared films were investigated via UV–visible spectroscopy. For all samples, the bandgap energy values were between 1.18 and 1.65 eV. Moreover, the refractive index and extinction coefficient of samples were about 1.14–1.40 and 0.1–0.6, respectively. Photocatalytic properties of the samples were investigated by measuring the degradation of methylene blue dye under simulated solar irradiation. We found that the heavy rare‐earth substituted BFO thin films have better photocatalytic activity compared to pure BiFeO3 thin film. It was observed that prepared thin films could remove between 37.18% and 77.24% of dye after 180 min irradiation. This study confirms that prepared thin films are a suitable candidate for photocatalytic applications. [ABSTRACT FROM AUTHOR]