Size Distribution Research Articles

Ytterbium Doping-Retooled Prussian Blue for Tumor Metabolism Interference Therapy.

Drug repurposing refers to excavating clinically approved drugs for new clinical indications, effectively shortening the cost and time of clinical evaluation due to the established molecular structure, pharmacokinetics, and pharmacodynamics. In this sense, clinically approved Prussian blue (PB) has received considerable attention, by virtue of its unique optical, magnetic, and enzymatic performance. Nevertheless, the clinical transformation of PB-based nanodrugs remains restricted owing to their complex synthetic formulation and constrained therapeutic performance. Herein, inspired by diagnostic and therapeutic superiorities of lanthanide ions, a series of ytterbium (Yb)-containing PB nanoparticles (NPs) are synthesized in one step through interstitial Yb-doping, which aims to improve the anticancer efficacy of PB and expand the biological application orientation of Yb ions. Through a systematic comparative analysis, involving microscopic morphology, size distribution, elemental composition, raw material utilization rate, and crystal structure, Yb-enriched PB NPs with better-balanced indexes are identified as an antineoplastic drug candidate. In parallel, their anticancer mechanisms are associated with the mammalian target of rapamycin (mTOR) and adenosine monophosphate-activated protein kinase (AMPK) pathways, thus disturbing anabolism, catabolism, and homeostasis. Therefore, this study attempts to implement the concept of drug repurposing and lays the foundation for next-generation theranostic nanodrugs.

3D cryo-printed hierarchical porous scaffolds provide immobilization of surface-functionalized sleep-inspired small extracellular vesicles: synergistic therapeutic strategies for vascularized bone regeneration based on macrophage phenotype modulation and angiogenesis-osteogenesis coupling

Bone defect healing is a multi-factorial process involving the inflammatory microenvironment, bone regeneration and the formation of blood vessels, and remains a great challenge in clinical practice. Combined use of three-dimensional (3D)-printed scaffolds and bioactive factors is an emerging strategy for the treatment of bone defects. Scaffolds can be printed using 3D cryogenic printing technology to create a microarchitecture similar to trabecular bone. Melatonin (MT) has attracted attention in recent years as an excellent factor for promoting cell viability and tissue repair. In this study, porous scaffolds were prepared by cryogenic printing with poly(lactic-co-glycolic acid) and ultralong hydroxyapatite nanowires. The hierarchical pore size distribution of the scaffolds was evaluated by scanning electron microscopy (SEM) and micro-computed tomography (micro-CT). Sleep-inspired small extracellular vesicles (MT-sEVs) were then obtained from MT-stimulated cells and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol)-inorganic pyrophosphate (DSPE-PEG-PPi) was used to modify the membrane of MT-sEVs to obtain PPi-MT-sEVs. RNA sequencing was performed to explore the potential mechanisms. The results demonstrated that PPi-MT-sEVs not only enhanced cell proliferation, migration and angiogenesis, but also regulated the osteogenic/adipogenic fate determination and M1/M2 macrophage polarization switch in vitro. PPi-MT-sEVs were used to coat scaffolds, enabled by the capacity of PPi to bind to hydroxyapatite, and computational simulations were used to analyze the interfacial bonding of PPi and hydroxyapatite. The macrophage phenotype-modulating and osteogenesis–angiogenesis coupling effects were evaluated in vivo. In summary, this study suggests that the combination of hierarchical porous scaffolds and PPi-MT-sEVs could be a promising candidate for the clinical treatment of bone defects.Graphical abstract

Extraction of E171 or E172 food additives from sugar-based or lipid-based complex matrices for primary particles identification by electron microscopy

Measurement of primary particle size distributions is fundamental to determining if a material should be classified as a nanomaterial according to the European Commission recommended definition. This is of particular relevance to alimentary products, where current regulation requires that any additives containing nanoforms be explicitly declared as such in the ingredients’ list. Currently, Electron Microscopy is the only instrumental technique able to reliably classify materials as nanomaterials. To verify the nanostatus of a material using this technique, it is essential to firstly extract the additives from the matrix in which they are dispersed, and then measure a wide size distribution while avoiding artefacts from the food matrix. In this operating procedure, extraction protocols, developed and applied for sugar-based or lipid-based food, are described. In particular, case studies for titanium dioxide E171 and iron oxide/iron hydroxide based materials such as E172 are considered. The protocols are based on gentle extraction of the additive materials and could, in principle, be used for other nanomaterials provided they are not soluble in water or ethanol and are resistant to enzymatic reactions. The size distribution of the extracted material can then be determined from images acquired using scanning and/or transmission electron microscopy.

Drying Controlled Synthesis of Catalytic Metal Nanocrystals Within 2D‐Material Nanoconfinements

AbstractThe synthesis of low‐dimensional metal nanocrystals with precise atom‐to‐nanoscale structure control is crucial for modulating their physicochemical properties. Traditional synthetic routes encounter challenges due to isotropic metallic bonding, which leads to limited control over metal nanostructures. Herein, a versatile approach is developed using various 2D material (2DM) nanoconfinements to produce a wide range of metal nanocrystals with controllable morphologies. Utilizing graphene oxide (GO) and Ti3C2Tx MXene nanosheets, thin multilayer films are assembled through vacuum filtration and are crosslinked with tetraammineplatinum(II) nitrate (TPtN), followed by in situ thermal reduction. By controlling the concentration of TPtN solution, precise loadings of platinum (Pt) are attained while preserving the nanoconfinement integrity. Two water removal techniques, air‐drying and freeze‐drying, are investigated to assess their impacts on resultant morphologies of Pt nanocrystals. Transmission electron microscopy and molecular dynamics simulations demonstrate high‐aspect‐ratio Pt nanosheets on MXene substrates and few‐atom Pt nanoclusters on GO substrates. A decrease in size distribution is observed upon the use of freeze‐drying. In the semihydrogenation reaction of phenylacetylene, freeze‐dried Pt–MXene heterostructures achieve a high turnover frequency of 2.93 s−1. This comprehensive study highlights the potential of utilizing 2DM nanoconfinement to synthesize metal nanostructures for catalysts and beyond.

Tracking the Evolution of Ionomer Film and Catalyst Material to Unravel PEMFC Performance Degradation

Abstract Several characterization techniques were performed on a proton exchange membrane fuel cell (PEMFC) to relate the performance degradation induced by the membrane-targeted accelerated stress test (AST) to the evolution of electrochemical and physical properties of the electrode. This works investigated the ionomer structure and the proton transport properties. Electron microscopy and small angle neutron scattering analysis provided access to the electrode’s nanoscale structure, the distribution of the platinum particle size, the structure of the 2-3 nm thick ionomer film, as well as the location of the water uptake by the electrode. A newly-developed technique using proton desorption under diluted O2 allows to distinguish effectively used active sites for oxygen reduction reaction. Proton transport and dioxygen diffusivity properties were measured using impedance spectroscopy and limiting current technique respectively. The Membrane-AST leads to an increase in the water uptake of the electrode due to a modification of the global structure of the electrode, a reduced platinum surface area, and corrosion of carbon particles. However, it does not alter the ionomer structure. The decrease in performance is partially attributed to the increase in proton resistivity, but mainly due to the limitation of dioxygen transport fostered by the electrode structure modifications.

Probabilistic cellular automata simulation of microstructure evolution: the role of model parameters on precision and uncertainty

Abstract Probabilistic cellular automata (PCA) is a widely used and cost-efficient method for simulating microstructural evolution. In this method, probabilistic state change rules determine the evolution of cell states at each time step. However, its stochastic nature introduces inherent uncertainty, leading to non-repeatable results. Most microstructural simulation studies assess the accuracy of simulations by comparing predicted results with experimental observations, neglecting uncertainties in mathematical models and algorithms. In this study, the precision and stochastic behavior of microstructure evolution in the PCA simulations were investigated. The probabilities of transformations of cell states at each time step were formulated, and discrete probability distribution functions (dPDF) were introduced to analyze the frequency distribution of simulation outcomes. The performance and consistency of these dPDFs were assessed by comparing statistical analyzes of PCA simulation results with dPDF predictions, revealing that the variance of simulation results is less than that of the binomial distribution function. Additionally, the effects of modeling parameters, such as model size, cellular resolution, and probability distribution of state changes in two- and three-dimensional PCA modeling, on the precision and reliability of simulation results were studied. In PCA models, simulation uncertainty inversely relates to the square root of model size. Furthermore, in 2D simulations, uncertainty is inversely proportional to the square root of the cellular resolution, while in 3D simulations, it is inversely proportional to the cellular resolution itself. These findings provide a simple and computationally efficient method for evaluating PCA simulation uncertainty and determining optimal simulation parameters, including model size, cellular resolution, and dimensionality.

Surface plasmon resonance to trace and measure cancer cell apoptosis using morphological and refractive index changes

Morphological changes of cancer cells are often used as an important indicator within efficiency studies of anticancer drugs. Morphological cell analysis on cell size and shape distribution is typically performed using microscopic methods, which are time consuming and require skilled personnel. Recently, more advanced image processing and pattern recognition have enabled identification and quantitative analysis of the cell’s abnormality and classification in an automated way. However, these methods usually involve multiple staining steps. In addition to computational complexity, the processes greatly compromise real-time applications of the system. Therefore, a non-invasive, real-time method allowing for assessment of living cells’ reactions to a death inducer is very much needed. Here, we present an SPR biosensor that measures the changes in cancer cells’ size and detachment, relating the cell confluency with the changes of the refractive index on the cell-substrate interface. As a proof-of-concept, we chose HeLa cell and hydrogen peroxide (H2O2) induced apoptosis as the model system to study the morphological changes of the cell. The results show that the SPR response to cell apoptosis agreed with the cellular morphological changes observed via microscopy. Interestingly, we observed simultaneous apoptosis and necrosis at high H2O2 concentrations. This simultaneous occurrence was verified using a mathematical model which incorporated other important factors such as cell thickness and intercellular refractive index. This model helped resolve the disagreement between SPR signal and cell confluency at high H2O2 concentrations. Our results show the potential of SPR as a label free and real time monitoring method for morphological changes and surface detachment of cancer cells. This method can be fully expanded to other cell-based sensing applications.

Chess-like Pieces Realized by Selective Laser Sintering of PA12 Powder: 3D Printing and Micro-Tomographic Assessment

The paper highlights the realization of 3D-printed parts with complex geometries, such as chess-like pieces, using polyamide 12 (PA12) as polymeric powder via selective laser sintering (SLS). The research activity focuses on the study of the powder printability, the optimization of the printing parameters, and the tomographic evaluation of the printed objects. Morphological analyses were carried out to study the PA12 powder microstructure considering that SLS required specific particle size distribution and shape, able to guarantee a good flowability necessary to take part in a sintering process. DSC and TG analyses were performed to determine the sintering window and the crystallinity degree, and to evaluate the thermal stability of the PA12 powder due to the importance of the powder processability for the SLS process. The novelty lies in the realization of chess-like pieces very challenging to print via SLS due to their different and highly detailed structures, and the in-depth analysis of the dimensional accuracy evaluated by micro-tomography. The 3D-printed samples obtained show high printing quality and dimensional stability. The μ-CT analysis also confirms the key role of the object shape and section changes on the final porosity of the chess-like pieces.

Relationship Between the Carbonation Depth and Microstructure of Concrete Under Freeze–Thaw Conditions

Concrete structures in cold regions are affected by freeze–thaw cycles (FTCs) and carbonation, which lead to the premature failure of concrete structures. The carbonation depth, relative dynamic elastic modulus (RDEM), compressive strength, porosity, and pore size distribution of concrete under FTC conditions were tested through an accelerated carbonation experiment to study the carbonation performance evolution. The freeze–thaw effect mechanism on concrete carbonation was further analyzed via the obtained relationship between carbonation depth and pore structure. The results showed that the FTC, as a powerful source of concrete damage, accelerates the carbonation reaction. Carbonization products fill some microcracks caused by the freeze–thaw process, improve the compressive strength and dynamic elastic modulus, and alleviate the damage to concrete caused by the FTC. After carbonization under freeze–thaw damage conditions, the content of macropores with d > 1000 nm decreases, while the content of transition pores with d ≤ 10 nm increases, which is the direct reason for the decrease in porosity and the improvement in strength. Therefore, the carbonation durability of concrete under freeze–thaw conditions can be improved by controlling the content of macropores with d > 1000 nm and increasing the content of transition pores with a pore size of 10 nm ≤ d < 100 nm. In addition, the relationship between carbonation depth and pore structure under freeze–thaw conditions was established, and the research results can provide a reference for the study of the carbonation performance of concrete under freeze–thaw conditions.

Parameters Governing Void Formation and Expansion of Hollow Natural Rubber Latex Particles for Their Use as Bio‐based Nanocapsules

AbstractThis work reports the hollow latex (HL) particles developed from natural rubber latex particles (NRPs), known for their broad size distribution and non‐spherical shape. HL‐NRPs, prepared via the seeded emulsion polymerization in one pot, are studied as potential bio‐based nanocapsules for the first time. Effects of types of crosslinking agents and swelling agents, the addition of sodium dodecyl sulfate (SDS), and monomer compositions on the void formation and expansion are systematically investigated. The combined effects of phase separation between NR core swelled with divinyl benzene (DVB) and hydrophilic poly(methyl methacrylate/acrylic acid) P(MMA/AA) shell, the entanglement of rubber chains copolymerized with MMA/DVB/AA monomers, and the osmosis from external aqueous medium promoted the void formation. While crosslinking agents affected the void formation and shell strength, SDS and type of monomers governed colloidal stability and polymerization loci as well as morphology, respectively. The ability of HL‐NRPs as nanocapsules is explored by encapsulating fluorescent dyes, i.e., hydrophilic fluorescein isothiocyanate (FITC) and lipophilic Nile red (NiR), as model cargo. From the dye release test after 24 h, the cumulative concentrations of FITC in methanol and of NiR in tetrahydrofuran are 0.17 and 0.11 µg mL−1, respectively. The results suggested that FITC is released from HL‐NRPs easier than NiR possibly due to the different encapsulation location.

Evaluation of Recycled and Reused Metal Powders for DMLS 3D Printing

Metal powders for additive manufacturing are expensive, and producing new ones from mined metals has a negative ecological impact. In this work, recycled and reused metal powders from MS1 steel for direct metal laser sintering (DMLS) 3D printing were evaluated in the laboratory. The powders were recycled by melting followed by gas atomizing. Virgin, recycled, and reused metal powders were evaluated using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), metallography analysis, microhardness measurements, particle size distribution (PSD), shape factor by digital image processing (DIP), and flowability testing. The results showed that the particle distribution was modified after recycling. Kurtosis analysis revealed a reduction from −0.64 for virgin powders to −1.29 for recycled powders. The results demonstrated a positive skewness, indicating that the recycled powder contained a greater proportion of smaller particles. The shape factor was also modified and changed from 1.57 for virgin powders to 1.28 for recycled powders. The microstructure also changed, and austenite was found in the recycled powders. The microhardness of recycled powder decreased by 39% compared to the virgin powder. Recycled powders did not flow, using two different funnels to evaluate their flowability. The flowability of used powder was reduced from 4.3 s to 2.9 s.

COMPARISON OF TWO METHOD FOR ISOLATION OF FIBRILLATED CELLULOSE FROM LIGNOCELLULOSIC BIOMASS

Fibrillated cellulose from distillery refuse based on maize starch was prepared by two different procedures. The effect of sonification was evaluated atacid-alkali extractionas well as the type of used acid. The results from the alkali-acid procedure were compared with these obtained by method of steam explosion at different temperatures. The acid-alkali method brings a better result regarding degradation of hemicellulose and lignin as well as cellulose. Lignin/hemicellulose were only released from lignocellulose network using steam explosion at 120-180°C. At higher temperature, the results were comparable with those obtained by acid-alkali method. Similarly pore size distribution of filter paper decreased more significantly when fibrillated cellulose from acid-alkali treatment was applied. After steam explosion, higher extend of longer still fibres remains.

Characterization and Optimization of Vesicle Properties in bioPISA: from Size Distribution to Post-Assembly Loading.

This study investigates the formation and properties of vesicles produced via biocatalytic Polymerization-Induced Self-Assembly (bioPISA) as artificial cells. Methods for achieving size uniformity, including gentle centrifugation and sucrose gradient centrifugation, are explored, and the effects of stirring speed on vesicle morphology is investigated. The internal structure of the vesicles, characterized by a polymer-rich matrix, is analyzed using fluorescence correlation spectroscopy (FCS). Additionally, the feasibility of loading macromolecules into pre-formed vesicles is demonstrated using electroporation, and a fluorescent protein as well as enzymes for a cascade reaction were sucesfully incorporated into the fully assembled polymersomes. These findings provide a foundation for developing enzyme-synthesized polymeric vesicles with controlled morphologies for various applications, e.g., in synthetic biology.

Oral Curcumin through Mesoporous Silica Nanomaterials with Distinct Morphologies: Synthesis, Characterization, Biosafety Evaluation, and Antioxidant Activity In Vivo.

Antioxidant play a crucial role in the prevention and treatment of diseases associated with oxidative stress. Curcumin (CUR), as a natural antioxidant, exhibits numerous therapeutic properties, including antioxidant, anti-inflammatory, antibacterial, and antitumor activities. However, its limited bioavailability and poor water solubility hinder its application as an effective antioxidant. In this study, a series of mesoporous silica nanomaterials with distinct morphologies, i.e., mesoporous silica nanoparticles (MSN) and mesoporous silica nanorods (MSR) were synthesized by a template-sediment-etching method. CUR was selected as a model drug and encapsulated into these nanomaterials to improve its bioavailability in vivo. The morphology and size distribution of MSN and MSR were determined through transmission electron microscopy (TEM) imaging and Zetasizer analysis. Fourier transform infrared spectroscopy (FTIR) spectra confirmed the successful encapsulation of CUR within these nanomaterials. Furthermore, these CUR-loaded silica nanomaterials, denoted as CUR@MSN and CUR@MSR, exhibited excellent DPPH and ABTS free radical scavenging activity in vitro. Furthermore, CUR@MSN and CUR@MSR also exhibited obvious in vivo antioxidant activity. This study opens up new avenues for the development of enhanced antioxidants through the utilization of mesoporous silica nanomaterials.

The effect of different water types commonly applied during laser diffraction measurement on the particle size distribution of soils

It is expected in the future that soil particle size distribution (PSD) measurements by laser diffraction method (LDM) may replace sieve-pipette sedimentation methods (SPM) as they are faster, require less sample, and are accurate and reproducible. LDM measurement result is a continuous function of PSD, which can facilitate the conversion between the various limits (by countries, by scientific field) of the calculated particle size fractions (PSF – e.g. clay, silt, sand). Currently, there is no standard method for LDM PSD measurement. Many different types of instruments and preparation devices are currently used in laboratories, with various sample preparation, pre-treatment and measurement methods (duration, chemical and/or mechanical dispersion, settings, etc.). In soil LDM PSD measurements, researchers put relatively little emphasis on the choice of the type of aqueous media used. Thus, it is still questionable to what extent the results of the LDM measurement depend on the selection of the dispersion method and the aqueous media. For our research, eight soil samples with various physical and chemical properties were collected in Hungary. The particle size fractions (clay, silt, sand) determined with LDM (Malvern Mastersizer 3000) measured in three types of aqueous media (distilled, deionized and tap water), in different combinations of two dispersion methods (no treatment, ultrasonic or chemical dispersion with Calgon and their combination) were compared. For the comparison, PSF results of the conventional sieve pipette method (SPM) were used as a reference. Our results showed that LDM measurement can achieve various degrees of dispersion with different preparations, in many cases only partial dispersion, disaggregation, sometimes re-aggregation, and flocculation of soil particles were observed as compared to full preparation (in SPM). The “disaggregation pattern” of the soil samples also depended on the quality of the aqueous media and the properties of the soil investigated, because several types and degrees of interactions could occur in the various soil-liquid-dispersant/disaggregation effect systems.

Ultrafine Particle Generation from Ozone Oxidation of Cannabis Smoke.

Cannabis smoke is a complex aerosol mixture, featuring characteristic monoterpenes and sesquiterpenes which are susceptible to reaction with ozone and other oxidants. These reactions form less-volatile species which can contribute to secondary organic aerosol (SOA) and ultrafine particle (UFP) formation. In this work, the reaction of ozone with cannabis smoke was observed in an environmental chamber. Particle size distribution, and gas-phase and particle-phase composition were monitored in real time. The diameter of primary particles ranged from 10-1 to 1 μm. Ultrafine particle formation occurred when cannabis smoke was exposed to ozone levels greater than 10 ppb, over the entire observed primary particle concentration range (1030-4580 μg m-3). Gas-phase measurements indicate that monoterpene and sesquiterpene levels decayed rapidly upon ozone exposure, while oxygen-containing species were formed during oxidation. On the other hand, measurements of particle composition showed an increase in nitrogen-containing species during oxidation. Although ozone was the only oxidant added to cannabis smoke in the chamber, it is believed that the OH radical plays an important role in the oxidation mechanism, where OH results from the reaction of ozone with terpenes and sesquiterpenes. Overall, smoking cannabis in ozone-rich environments, both indoors and outdoors, will likely lead to UFP formation.

Modeling the Influence of Deposition Parameters on the Crystalline Degree in the Simulation of Polycrystalline Silicon

Polycrystalline silicon (poly‐Si) has been and still is a pivotal material, particularly in the electronics and solar energy industries. Controlling crystallization is one of the challenges, e.g., in producing poly‐Si films for radio frequency applications. Since film growth by deposition is a random process, producing a specific grain size distribution for poly‐Si is challenging. By combining molecular dynamics simulation data with surface diffusion physics, novel transparent models are constructed that shed light on the physics behind the deposition of poly‐Si thin films and assist the selection of simulation parameters. Both probabilistic and geometric approaches are used to find relevant simulation parameters and their bounds to describe the complex grain–grain boundary interactions in the growth of poly‐Si thin films. Poly‐Si growth simulations provide valuable information to better understand the features of optimal growth conditions. The constructed parameterized deposition model is fitted to the simulation data. In addition to further refining the simulation of customized poly‐Si films, the presented modeling concept can also be used more generally in the analysis of physical vapor deposition.

Field measurements and modelling of climate driven hydraulic flux, water content and suction in a loess slope

Rainfall-triggered shallow slope failures are common in New Zealand loess. While often unsaturated, rainfall infiltration reduces suction in the loess as the water content increases, resulting in reduction in shear strength and increased potential for slope instability. Here the hydraulic response of an in-situ loess slope to natural rainfall and evapotranspiration is examined using long term field instrumentation. Data from a 19-month monitoring period show that the loess’ hydraulic behaviour responds to change in seasonal climatic conditions, highlighting the relationship between moisture content and suction with evapotranspiration and infiltration. To simulate the field response, a one-dimensional steady infiltration/evapotranspiration model has been developed, exploiting the unique power laws which interrelate water content, suction and hydraulic conductivity which arise from a loess’s fractal particle and pore size distributions. Hydraulic hysteresis is also accounted for. Closed form expressions are derived for the subsurface suction profile, from which profiles of moisture content, hydraulic conductivity and the suction’s contribution to strength may be obtained. Simulated subsurface water contents are in good agreement with field observations. Furthermore, fluxes across the loess surface used to obtain the modelled quantities are in general agreement with local climatic conditions and their variations during the monitoring period. Modelled and measured data are strongly correlated at shallow depths, having a Pearson correlation coefficient of 0.53.

Preparation of High‐Selectivity Li+ Adsorbents Based on Bauxite via Liquid‐Phase Alkaline Thermal Activation

ABSTRACTBauxite, as the main aluminium‐bearing mineral in China, is a crucial resource for the industrial production of aluminium and aluminium‐related products. In this study, bauxite‐based aluminium composite Li+ adsorbents were prepared using a liquid‐phase alkaline thermal activation—acid in situ method. The effects of various factors on Li+ adsorption from brine were investigated through single‐factor experiments. Multiple techniques, such as scanning electron microscopy (SEM), energy dispersive x‐ray spectroscopy (EDS), x‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET) method, Fourier transform infrared spectroscopy (FT‐IR), and x‐ray photoelectron spectroscopy (XPS), were employed to characterise and analyse the microstructure, pore size distribution, chemical element distribution, and mineral structure of the adsorbents. In addition, the changes in bauxite structure and properties before and after functionalization were investigated. Results indicate that the adsorption capacity of LATA‐AIS‐LDH‐BX adsorbent prepared by the acid in situ method reached 1.15 mg/g at pH = 7; the adsorption capacity of LATA‐Al‐LDH‐BX adsorbent prepared by the aluminium salt conversion method reached 2.16 mg/g. The adsorption behaviour of both adsorbents followed the pseudo‐second‐order kinetic model and the Langmuir model. In the presence of interfering ions (Na+, K+, SO24+, Mg2+), the composite adsorbents showcased strong selective adsorption capacity for Li+. After five cycles of adsorption–desorption, the adsorption rates decreased by 12.19% and 11.48%, respectively, demonstrating good recycling stability. Furthermore, the Li+ adsorption capacities in salt lake brine reached 0.82 mg/g and 1.48 mg/g, indicating promising potential for industrial application.

The Luna Analog Facility testbeds (ESA, EAC): contemporary characterization work of highland (lunar) and mare (EAC-1) lunar regolith simulants

The Luna Analog Facility, a joint ESA-DLR endeavour, consists of three components and spans an area of 1,000 m2, providing testbeds of simulated lunar environments. The main sections within the facility are a large area filled with lunar mare regolith simulant resembling mare regions and a smaller, individual “Dust Chamber”. The latter replicates highland conditions and contains approximately 20 tons of material, specifically simulating the fine-particle lunar regolith portion up to 250 µm. The Dust Chamber serves as a platform for testing various technologies, such as mechanical tools, robotic operations, in-situ resource utilization activities, and astronaut attire, as well as different procedures including rover and astronaut tasks. This work represents the geotechnical, geochemical and mineralogical characterization of the Lumina Sustainable Materials Ltd. 2023 batch highland simulants, from which Lunar250 is intended for use in the Luna Dust Chamber. Additionally, this work provides new results for ESA’s mare simulant, EAC-1. We provide data on particle size distribution, particle shape, abrasivity, density, water content, major and trace element geochemistry and modal mineralogy. As the simulants in the Luna Facility will be constantly overseen, this work organized by the Vulcan Facility (ESA) intends to support the monitoring of the geotechnical property variations of the simulants over time. Ultimately, we analysed several properties with different tools to emphasize how different methods and instruments affect the variability and reliability of the results.