Rare earth oxides (RE2O3) were found to react with glycine in an aqueous medium at rather low temperatures (60 degrees & Scy;-120 degrees & Scy;), forming rare earth oxohydroxyglycinates, RE2O(OH)(3)(NH2CH2COO)& centerdot;H2O, with a previously unknown crystal structure. The structure of the europium oxohydroxyglycinate was determined using powder X-ray diffraction. Its layered structure and ability for anion exchange under mild conditions, namely the exchange of glycinate ions for dodecyl sulfate ions, makes it similar to layered rare earth hydroxides (LREHs). However, according to the crystal structure and extended X-ray absorption fine structure data, in europium oxohydroxyglycinate, europium cations possess low coordination numbers, 6 and 7, which are very untypical for LREHs but typical for rare earth oxides. This suggests that rare earth oxohydroxyglycinates should be placed in a separate group of layered rare earth compounds that are similar to both LREHs and RE2O3. Interestingly, under similar synthetic conditions, the closest analogs of glycine, namely alanine, and phenylalanine, do not react with rare earth oxides, which enables the assumption that the formation of rare earth oxohydroxyglycinates proceeds through the topotactic reaction.

Polymer gels were obtained by dissolution of polyamide 6,6 in dimethylacetamide in the presence of lithium chloride. Supercritical drying of these gels allowed to obtain polymer aerogels with specific surface areas of 20–70 m2/g, specific pore volume of 0.1–0.4 cm3/g and porosity of 60–90

In the original publication [...].

Malonate ligands demonstrate versatility for intercalating metal complexes into layered rare-earth hydroxides (LREHs), enabling controlled tuning of coordination geometry and composition. As a proof of concept, a series of copper(II) malonate complexes with various substituents was synthesized and successfully intercalated into layered yttrium, europium, or terbium hydroxide at room temperature via anion-exchange reactions. The copper content in these hybrid materials increased in the order: butylmalonate < benzylmalonate < cyclopropanedicarboxylate < dimethylmalonate. To further expand the range of accessible metal malonate complexes, dimethyl- and benzylmalonate anions were intercalated into layered yttrium hydroxide for the first time and subsequently metalated in situ, yielding well-defined Cu2+ species within the interlayer space without disrupting the host lattice. Density functional theory (DFT) calculations provided insight into the structural arrangements of the copper complexes in the interlayer galleries. Comprehensive characterization of the resulting materials by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), IR, UV-vis, and electron paramagnetic resonance (EPR) spectroscopy confirmed both the successful formation of hybrid structures and elucidated the coordination environment of the intercalated copper species.

Hydrothermal treatment of nanoscale ThO 2 in a sodium–phosphate buffer yields a previously uncharacterized hydrated sodium–thorium phosphate with pH-dependent phase evolution.

Using various solvents (dioxane, n-butanol, isopropanol, ethanol, acetonitrile, dimethyl sulfoxide), the cogelation of methyltrimethoxysilane and tetraethoxysilane in a molar ratio of 1 : 1 was carried out. The resulting gels were dried in supercritical carbon dioxide to obtain SiO2 aerogels, which possessed specific surface areas of 1000–1500 m2/g, apparent densities of 0.055–0.095 g/cm3, and porosities of 95–99

New composite materials (ionogels) have been obtained based on imidazolium ionic liquids immobilized in highly porous polymers, i.e., polyamide 6,6 (nylon 6,6) and low-density polyethylene. A method has been proposed for determining the rate of ionic liquid removal from an ionogel upon contact with water, with this method being based on continuous measuring the conductivity of an aqueous phase. The results of the conductometric measurements have been confirmed by high-performance liquid chromatography data. It has been shown that the stability of ionogels upon contact with water is determined by both the hydrophobicity of a polymer matrix and the solubility of an ionic liquid in water. The highest degree of ionic liquid removal (more than 80%) has been observed for composites based on porous polyamide 6,6 (hydrophilic matrix) and dicyanimide 1-butyl-3-methylimidazolium (completely miscible with water). Ionogels based on low-density polyethylene (hydrophobic matrix) and bis(trifluoromethylsulfonyl)imide 1-butyl-3-methylimidazolium (poorly soluble , <1 wt %, in water) have shown the highest stability (washout degree of no more than 53% over 24 h). The method proposed for analyzing the rate of ionic liquid dissolution in water has been used to discuss the mechanism of this process.

Purpose of the study: the creation of a dextran coating on cerium oxide crystals using different ratios of cerium and dextran to synthesize nanocomposites, and the selection of the best nanocomposite to develop a nanodrug that accelerates quality wound healing with a new type of antimicrobial effect. Materials and methods: Nanocomposites were synthesized using cerium nitrate and dextran polysaccharide (6000 Da) at four different initial ratios of Ce(NO3)3x6H2O to dextran (by weight)—1:0.5 (Ce0.5D); 1:1 (Ce1D); 1:2 (Ce2D); and 1:3 (Ce3D). A series of physicochemical experiments were performed to characterize the created nanocomposites: UV-spectroscopy; X-ray phase analysis; transmission electron microscopy; dynamic light scattering and IR-spectroscopy. The biomedical effects of nanocomposites were studied on human fibroblast cell culture with an evaluation of their effect on the metabolic and proliferative activity of cells using an MTT test and direct cell counting. Antimicrobial activity was studied by mass spectrometry using gas chromatography–mass spectrometry against E. coli after 24 h and 48 h of co-incubation. Results: According to the physicochemical studies, nanocrystals less than 5 nm in size with diffraction peaks characteristic of cerium dioxide were identified in all synthesized nanocomposites. With increasing polysaccharide concentration, the particle size of cerium dioxide decreased, and the smallest nanoparticles (<2 nm) were in Ce2D and Ce3D composites. The results of cell experiments showed a high level of safety of dextran nanoceria, while the absence of cytotoxicity (100% cell survival rate) was established for Ce2D and C3D sols. At a nanoceria concentration of 10−2 M, the proliferative activity of fibroblasts was statistically significantly enhanced only when co-cultured with Ce2D, but decreased with Ce3D. The metabolic activity of fibroblasts after 72 h of co-cultivation with nano composites increased with increasing dextran concentration, and the highest level was registered in Ce3D; from the dextran group, differences were registered in Ce2D and Ce3D sols. As a result of the microbiological study, the best antimicrobial activity (bacteriostatic effect) was found for Ce0.5D and Ce2D, which significantly inhibited the multiplication of E. coli after 24 h by an average of 22–27%, and after 48 h, all nanocomposites suppressed the multiplication of E. coli by 58–77%, which was the most pronounced for Ce0.5D, Ce1D, and Ce2D. Conclusions: The necessary physical characteristics of nanoceria–dextran nanocomposites that provide the best wound healing biological effects were determined. Ce2D at a concentration of 10−3 M, which stimulates cell proliferation and metabolism up to 2.5 times and allows a reduction in the rate of microorganism multiplication by three to four times, was selected for subsequent nanodrug creation.

The structure and hardness of an aluminum-matrix Al–Si–Cu-based material reinforced with WO3 nanoparticles via liquid phase mixing with a melt according to two versions, namely, using a mixture of WO3 with a copper powder and without it, are studied. The existence of transport effect of a copper powder, which ensures a uniform distribution of WO3 nanoparticles in the composite volume, is confirmed. The most homogeneous structure and a high hardness of the composite material are reached in the case of introduction of a mixture of 1 wt

— Single crystals of Hg 1– х Cd x Cr 2 Se 4 solid solutions with the normal spinel structure have been prepared via thermal annealing and characterized by X-ray microanalysis. Thermal annealing is a viable alternative to a previously proposed method: flux growth with CdCl 2 as a solvent. Doping of the solid solutions with gallium and/or gallium selenide has been shown to ensure a considerable increase in the Curie temperature of the material.

CeO 2 surface is crucial for dissolution process. Untreated nanoparticles are more soluble than dried ones due to their hydrated state. Dried CeO 2 solubility increases as the surface returns to a hydrated state, ensuring long-term stability.

The issue of the qualitative and quantitative analysis of the concentration of oxidising species in aquatic environments is crucial for a wide range of biological and environmental tasks. In particular, reactive chlorine species, specifically hypochlorite (ClO−), play a significant biochemical role in the operation of the immune system. There is also the challenge of determining the presence of ClO− in purified drinking water that is supplied by water treatment systems. Traditional chemical analytical methods often lack the required selectivity and sensitivity to detect oxidising compounds, and chemiluminescence-based techniques offer an alternative solution. In this study, we propose a simple and selective approach for the chemiluminescent detection of hypochlorite in aqueous media under neutral conditions. The technique is based on measuring a chemiluminescent signal generated in the presence of hypochlorite by a combined probe comprising commercially available WS2 quantum dots and luminol. The oxidation of WS2 with hypochlorite followed by a reaction with luminol results in an intense luminescent signal that enables the selective determination of hypochlorite under neutral conditions. The greatest sensitivity with this method was achieved when combining WS2 quantum dots with L-012, a highly sensitive analogue of luminol. Additionally, the use of L-012 improved the detection limit for hypochlorite to 2 × 10−6 M. Due to its selectivity in determining hypochlorite in the presence of reactive oxygen species (hydrogen peroxide) under neutral conditions with high sensitivity and with a wide linear range, the proposed approach provides an attractive analytical tool for the analysis of water samples and biological liquids.

A method was developed to produce aqueous sols of nanocrystalline hafnium dioxide (with a hydrodynamic diameter of 20–35 nm), which were stabilized by lactic acid (lactate ions) and characterized by high colloidal stability (ζ-potential –29 mV). The method is based on hydrothermal treatment of a preliminarily obtained complex compound of hafnium with lactic acid in the presence of urea at temperatures of 180 and 220°C for 48 and 96 h. Chemiluminescent analysis in a model reaction of luminol oxidation determined that nanocrystalline hafnium oxide in the sols exhibits dose-dependent prooxidant activity toward hydrogen peroxide and thus has peroxidase-like properties.

The immobilisation of ionic liquids (ILs) in porous solid matrices enables the design of ionogels, which are now regarded as a promising material in extraction science. Here, by the co-gelation of TMOS and MTMS in a commercially available ionic liquid, Aliquat 336 (A336Cl), a series of ionogels were synthesised with various levels of IL content and matrix hydrophobicity. Both of these factors were shown to have a small effect on Fe(III) extraction efficiency (57-70 %), while they strongly influenced the re-extraction efficiency (15-45 %) of the materials. The ionogels with the highest IL content (80 %) and a highly hydrophilic silica matrix showed the best extraction and re-extraction performance. A thorough characterisation of the ionogels confirmed the confinement of the IL in silica and revealed Fe(III) extraction mechanisms. It was shown that iron was extracted from the aqueous solutions by A336Cl@SiO2 ionogels in the form of FeCl4- ions typical of the extraction by pure A336Cl. Unexpectedly, the iron extraction by the ionogels resulted in the formation of Fe2Cl7- species that had not been observed earlier in the A336Cl-based extraction systems. Moreover, iron(III) directly bound to hydrophilic silica through Si-O-Fe bridges, and it was also found that, in the ionogels, the admixtures of alcohols could even reduce ferric ions to ferrous species. For the ionogels, both iron extraction and re-extraction followed pseudosecond order kinetics. Iron re-extraction from the ionogels with aqueous sulfuric acid solution resulted in the loss of recyclability, most probably due to the formation of FeSO4 & sdot;H2O in the ionogels. The cycling performance of the ionogels can be improved by their conditioning in chloride-rich media after re-extraction stages.

The movement of small particles and molecules through nanopore membranes is widespread and has far-reaching implications. Consequently, the development of mathematical models is essential for understanding these processes on a micro level, leading to deeper insights. In this endeavor, we suggested a model based on a set of empirical equations to predict the transport of substances through a solid-state nanopore and the associated signals generated during their translocation. This model establishes analytical relationships between the ionic current and electrical double-layer potential observed during analyte translocation and their size, charge, and mobility in an electrolyte solution. This framework allows for rapid interpretation and prediction of the nanopore system's behavior and provides a means for quantitatively determining the physical properties of molecular analytes. To illustrate the analytical capability of this model, ceria nanoparticles were investigated while undergoing oxidation or reduction within an original nanopore device. The results obtained were found to be in good agreement with predictions from physicochemical methods. This developed approach and model possess transferable utility to various porous materials, thereby expediting research efforts in membrane characterization and the advancement of nano- and ultrafiltration or electrodialysis technologies.

The combination of ultrasonic exposure on ceric phosphate gels with subsequent hydrothermalmicrowave treatment resulted in the formation of nanoscale NH 4 Ce 2 (PO 4 ) 3 or KCe 2 (PO 4 ) 3 phases. The sun protection factor (SPF) and protection factor against UV -A radiation (UVAPF) values for double ceric phosphates with the smallest crystallite sizes exceeded 4 and 3.5, respectively, which is much higher than the values for samples consisting of larger particles. These results are superior to previously published values for similar ceric compounds, and thus show promise for their application in sunscreens.

Ionogels were obtained by impregnating Aerosil A380 with 1-methyl-3-octyl-imidazolium tetrafluoroborate (OMIM BF4) ionic liquid (IL). The IL content of the ionogels varied from 16.3 to 79.9 mol %. There was evidence of the confinement of the IL in silica in the shift and broadening of the BF4 - 19F NMR signal and in the noticeable (similar to 50 degrees C) decrease in the temperature of IL decomposition. For both the ionogels and the pure IL, the frequencies of IR vibrations were different, providing further evidence of the confinement effect. An analysis of textural characteristics revealed that, upon its addition to Aerosil, the IL sequentially adsorbed in the micropores, mesopores and interparticle space. SAXS measurements showed that, in the confined IL, the size of nonpolar correlations substantially increased, from 21.5 & Aring; in the bare IL to 25.6 & Aring; in the ionogel containing 28.1 mol % IL. Unexpectedly, for the ionogel with the lowest IL content (16.3 mol %), no nonpolar correlations were observed, indicating the strong distortion of the structure of the confined ionic liquid. To the best of the authors' knowledge, this is the first report on regular changes in nonpolar correlations in ionic liquids upon confinement in a porous solid. These structural correlations can easily be tuned by simply changing the IL content in the ionogel material.

One step method of iron oxides nanoparticles synthesis using novel type of microreactors was reported. All the data received from analysis of physical and chemical properties demonstrated that the nanoparticles obtained by means of the new method are similar to the nanopowders synthesized by wet precipitation. They are magnetite-maghemite solid solutions with unit cell parameter between 8.362 and 8.374Å, with coherent scattering range values about 9nm. In comparison with precipitated nanopowders they have lesser degree of agglomeration. Samples obtained in microreactor have smaller value and smaller spread in regard of the specific surface (76-86 m2/g) in comparison with precipitated ones (75-125 m2/g). All the samples from microreactor consist of spherical inhomogeneities with a diffuse surface, while sample of iron oxide nanopowder synthesized by the co-precipitation method consists of scattering cylindrical inhomogeneities with nearly smooth phase boundary. It was shown that microreactor with intensively swirling flows has demonstrated several advantages: (i) possibility to control the degree of oxidation of the product which depends on the flow rates of reagents solutions to the reactor; (ii) high productivity (up to 7L/min for the suspension with particles, approx. 200kg/day for the dried particles) that eases the scaling-up of the proposed synthesis method.

Although the most promising applications of ionogels require their contact with aqueous media, few data are available on the stability of ionogels upon exposure to water. In this paper, a simple, easy-to-setup and precise method is presented, which was developed based on the continuous conductivity measurements of an aqueous phase, to study the washout of imidazolium ionic liquids (IL) from various silica-based ionogels immersed in water. The accuracy of the method was verified using HPLC, its reproducibility was confirmed, and its systematic errors were estimated. The experimental data show the rapid and almost complete (>90% in 5 h) washout of the hydrophilic IL (1-butyl-3-methylimidazolium dicyanamide) from the TMOS-derived silica ionogel. To lower the rate and degree of washout, several approaches were analysed, including decreasing IL content in ionogels, using ionogels in a monolithic form instead of a powder, constructing ionogels by gelation of silica in an ionic liquid, ageing ionogels after sol–gel synthesis and constructing ionogels from both hydrophobic IL and hydrophobic silica. All these approaches inhibited IL washout; the lowest level of washout achieved was ~14% in 24 h. Insights into the ionogels’ structure and composition, using complementary methods (XRD, TGA, FTIR, SEM, NMR and nitrogen adsorption), revealed the washout mechanism, which was shown to be governed by three main processes: the diffusion of (1) IL and (2) water, and (3) IL dissolution in water. Washout was shown to follow pseudo-second-order kinetics, with the kinetic constants being in the range of 0.007–0.154 mol−1·s−1.