Varying Particle Size Research Articles

The Biological Properties of Co-Doped Monetite Are Influenced by Thermal Treatment.

Calcium phosphates, notably monetite, are valued biomaterials for bone applications owing to their osteogenic properties and rapid uptake by bone cells. This study investigates the enhancement of these properties through Cobalt doping, which is known to induce hypoxia and promote bone cell differentiation. Heat treatments at 700°C, 900°C, and 1050°C are applied to both monetite and Cobalt-doped monetite, facilitating the development of purer, more crystalline phases with varied particle sizes and optimized cellular responses. Comprehensive physicochemical characterization through XRD, FTIR, Raman, SEM/EDS, and ASAP analyses shows significant phase transformations into pyrophosphate, influencing the materials' structural and functional attributes. When utilized to condition a culture medium for MC3T3-E1 cells, these materials demonstrate non-cytotoxic behavior and provoke specific gene responses associated with the osteoblastic phenotype, angiogenesis, adhesion, and extracellular matrix remodeling. Significantly, non-heat-treated Cobalt-doped Monetite retains properties advantageous for clinical applications such as dental and orthopedic implants, where lower processing temperatures are crucial. This attribute, combined with the material's straightforward production, highlights its practicality and potential cost-effectiveness. Further research is essential to assess the long-term safety and efficacy of these materials in clinical settings. Our findings underscore the promising role of Cobalt-doped Monetite in advancing bone repair and regeneration, setting the stage for future innovations in treating bone lesions, enhancing implant integration, and developing advanced prosthetic coatings within the field of tissue engineering.

Achieving synergistic enhancement in the anaerobic digestion of corn straw by (CH4+CO2) nanobubbles in conjunction with optimized particle sizes.

Nanobubbles (NBs) technology has been proven to promote methane production from anaerobic digestion (AD). In this study, the synergistic effects of (CH4+CO2)-nanobubble water ((CH4+CO2)-NBW) combined with varying particle sizes of corn straw on the AD were investigated. As findings, adding (CH4+CO2)-NBW effectively promoted the methane production from AD of corn straw with different particle sizes. The maximum cumulative methane yield (186.42mL/ g-volatile solids) was achieved in Group a with the addition of (CH4+CO2)-NBW, representing a 16.89% increase compared to the control. Furthermore, (CH4+CO2)-NBW could enhance the enzymatic activity. The activities of β-glucosidase and coenzyme F420 were increased by 6.70% and 11.48%, respectively. The results of microbial community structure revealed that the addition of (CH4+CO2)-NBW could improve the abundance of dominant bacteria (norank_JS1, norank_Aminicenantales, and Bacteroidetes_vadinHA17) and archaea (Methanomassiliicoccaceae, Methanobacteriaceae, and norank_Bathyarchaeia). This study provides new insights into the application of nanobubbles in the AD of biomass.

Size-Dependent Reduction Kinetics of Iron Oxides in Single and Mixed Mineral Systems.

Iron(III) (oxyhydr)oxide minerals with varying particle sizes commonly coexist in natural environments and are susceptible to both chemical and microbial reduction, affecting the fate and mobility of trace elements, nutrients, and pollutants. The size-dependent reduction behavior of iron (oxyhydr)oxides in single and mixed mineral systems remains poorly understood. In this study, we used microbial and mediated electrochemical reduction approaches to investigate the reduction kinetics and extents of goethite and hematite. We found that small particles were preferentially reduced relative to their large counterparts in single and mixed mineral systems regardless of microbial or electrochemical treatments, which is attributed to the combined effect of higher thermodynamic favorability and greater surface availability. In mixed mineral systems, small particles were reduced slightly faster, whereas large particles were reduced notably slower and less extensively than solely predicted from single mineral systems. Specifically, when reduced alone, small particles showed Fe(III) reduction rate constants that were 1.5- to 3.6-fold higher than large particles, while when reduced together, the reduction rate constants for small particles were 6- to 21-fold higher than the rate constants for large particles. These collective findings provide new insights into the pivotal role of nanoparticulate iron (oxyhydr)oxides in environmental redox reactions.

A Study on the Iodine Vapor Adsorption Performance and Desorption Behavior of HKUST-1 with Varying Particle Sizes

A Study on the Iodine Vapor Adsorption Performance and Desorption Behavior of HKUST-1 with Varying Particle Sizes

Combined exposure to microplastics and copper elicited size-dependent uptake and toxicity responses in red swamp crayfish (Procambarus clarkia).

In recent years, the toxicity of microplastics (MPs) in combination with heavy metals, particularly the influence of varying microplastic sizes on their toxic effects, has attracted widespread attention. In this study, red swamp crayfish (Procambarus clarkia) were exposed to MPs of two particle sizes (S-MPs: 5 μm, 1 mg/L; and L-MPs: 100 μm, 1 mg/L) and Cu (5 mg/L) individually or in combination for 96 h. The accumulation patterns of MPs were as follows: gills > intestines > hepatopancreas > muscles. Moreover, the accumulation pattern of Cu was as follows: intestines > gills > hepatopancreas > muscle. Additionally, S-MPs and L-MPs enhanced Cu accumulation, with the highest levels observed in the S-MPs+Cu-treated group. Histopathological analysis showed that the combined exposure led to greater hepatopancreatic damage. Assessment of antioxidant enzymes showed decreased activities of superoxide dismutase, catalase, and glutathione among the different treatments, except for malondialdehyde, which was elevated compared to the control group. In the S-MPs+Cu-treated group, the expression levels of Cu homeostasis genes (MTF-1, ATP2, Atox1, MT) were significantly lower than those in the Cu treated group. This study provides a valuable reference for studying the combined toxic effects of MPs with varying particle sizes on heavy metals.

Unveiling the impact of biodegradable polylactic acid microplastics on meadow soil health.

Soil microplastics (MPs) pollution has garnered considerable attention in recent years. The use of biodegradable plastics for mulching has led to significant quantities of plastic entering agro-ecosystems. However, the effects of biodegradable polylactic acid (PLA) plastics on meadow soils remain underexplored. This study investigates the impacts of PLA-MPs of varying particle sizes and concentrations on soil physicochemical properties, enzyme activities, and microbial communities through a 60-day incubation experiment. PLA-MPs increased the pH, soil organic matter, total nitrogen (TN) and available potassium (AK) content, as well as enhanced the activities of superoxide dismutase (S-SOD), peroxidase (S-POD), soil catalase (S-CAT), β-glucosidase (S-β-GC) and urease (S-UE) activities. Conversely, a decrease in alkaline phosphatase (S-ALP) activity was observed. The influence of PLA-MPs on soil physicochemical properties was more pronounced with larger particle sizes, whereas smaller particles had a greater effect on enzyme activities. Additionally, PLA-MPs led to an increase in the abundance of Acidobacteriota, Chloroflexi, and Gemmatimonadota, while the abundance of Proteobacteria, Actinobacteriota, and Patescibacteria declined. Mantel test analysis showed that changes in microbial community composition affected soil properties such as pH, AK, S-UE and S-β-GC. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt2) analysis demonstrated that PLA-MPs modify bacterial metabolic pathways. Our results suggest that particle size and concentration of PLA-MPs differentially affect soil nutrients and microbial community structure and function, with more significant effects observed at larger particle sizes and higher concentrations.

Liquid metal electrodes enabled cascaded on-chip dielectrophoretic separation of large-size-range particles.

The separation of large-size-range particles of complex biological samples is critical but yet well resolved. As a label-free technique, dielectrophoresis (DEP)-based particle separation faces the challenge of how to configure DEP in an integrated microfluidic device to bring particles of various sizes into the effective DEP force field. Herein, we propose a concept that combines the passive flow fraction mechanism with the accumulative DEP deflection effect in a cascaded manner. This concept places DEP deflection segments and bypass outlets alternately. Each DEP deflection segment is configured with an array of side-wall liquid metal electrodes to exert effective DEP forces on the particles of a suitable size range. After each DEP deflection segment, the passive bypass flow fraction mechanism diverts part of the sample flow and target range of particles through the bypass outlet. Simultaneously, this flow fraction brings the remaining particles closer to the electrodes in the subsequent DEP deflection segment, causing the next size range of particles to deflect under effective DEP forces and thus making them separable. Repeating this process, particles would be separated from the bypass outlets one by one in the order of reducing size ranges. We present the concept design and modeling, and prove the concept through separating five different particles ranging from 16-0.5 μm mixed together to mimic blood composition, providing a powerful platform for separating multiple particles in diverse biomedical applications.

Evaluation of wave-induced flow through marine porous media accounting for transition of seepage properties across multiple flow regimes

Wave-induced flow through marine porous media has been attracting coastal engineers and researchers because of their strong correlation with scouring, internal erosion, piping and other destructions of marine porous structures. Previous studies chose Darcy-Forchheimer equation for wave-induced seepage behavior analyses because of its simplicity and perceptiveness. However, numerous experiment observations suggested that significant flow regime transition occurred in porous media with high variations in porosity and particle size, while Darcy-Forchheimer equation is only applicable to flow within Forchheimer regime. In this paper, a mathematical model linking the resistance of porous medium to its porosity and particle size is proposed to characterize the seepage properties across Darcy and Forchheimer regime under wave loadings. The proposed seepage model is then incorporated into volume-averaged Reynolds-averaged Navier-Stokes equations, and thus enabling evaluating fluid motions in waves and marine porous media via a unified framework. Through validation against experimental observations, analytical solutions and well accepted computed results in the literature, the proposed model is shown to replicate the characteristics of resistance of porous media with different porosities and particle sizes under different flow regimes. Numerical analyses are conducted to elucidate that seepage velocities of wave-induced flow in marine porous materials can be over- or under-estimated if not considering transitional seepage properties across multiple flow regimes. Such discrepancies can become significant when strong variations occur in porous media with respect to particle size and/or porosity.

Interaction of cesium compounds with abundant inorganic compounds of atmosphere: Effect on cloud formation potential and settling.

Experiments were conducted in controlled laboratory conditions to determine the size-resolved CCN (Cloud Condensation Nuclei) activity of sub micrometer-sized aerosols containing nuclear fission products (CsI and CsOH) and abundant ambient inorganic aerosols ammonium sulphates ((NH4)2SO4), ammonium chloride (NH4Cl), sodium nitrate (NaNO3), and sodium chloride (NaCl). The presence of these atmospheric-relevant compounds internally mixed with fission product compounds has the potential to affect the capacity of ambient particulates of aerosols to absorb water and function as CCN. Once in the atmosphere, the dynamics of airborne radionuclides and subsequently their fate gets affected by dry and wet deposition processes. The interplay of source and decay terms determines the transit of radioactivity and impacts its local and/or global spread. After being exposed to a sufficiently humid atmosphere, released cesium particles have a high potential to act as CCN. However, the CCN properties of the resulting mixed particles may be altered due to their interaction with atmospheric particles. DMT-CCN counter was used to acquire CCN activation curves with initial dry particle size variation (20-300 nm) for mixed particles (ratio 1:1) at 0.1-1 % supersaturation (SS). For a variety of particle sizes and mixtures of soluble materials, activation ratio curves were obtained under various SS conditions. From the study of CCN spectra, an estimate of the hygroscopicity parameter (κ) was made, which is sensitive to the chemical composition of aerosols. Under different SS conditions, the CCN activation diameters of mixed aerosols were found to be affected greatly in comparison to pure compounds. For the first time, the spectral efficiency of CCNs and the activation diameters of CsI and CsOH particles combined with important atmospheric aerosols were described at various SS levels. Terminal settling velocities for the mixed particles having a representative diameter as critical activation droplet diameter (wet diameter at particular SS), and varying effective density (based on droplet composition) were obtained and compared with the pure state of particles at different SS levels. The relative difference was significant for some combinations and SS conditions. Any modification in settling velocity ultimately impacts the particle's lifetime and deposition flux estimations. Hence neglecting the presence of atmospheric salts affects the accuracy of the source term estimates for a postulated nuclear reactor accident scenario. Data on these features is crucial for modelling the behavior of these particles in simulations. In the extremely improbable event of a containment breach occurring under severe nuclear accident conditions, the outcome has the potential to enhance environmental source-term estimations.

Enhancing thermal efficiency of parabolic trough collectors using SiO2 nanofluids: a comparative study of particle size impact on solar energy harvesting

ABSTRACT Solar energy technologies, particularly Parabolic Trough Solar Collectors (PTSCs), are crucial for efficient and scalable thermal applications in Concentrated Solar Power (CSP) plants. This study investigates the thermal efficiency of PTSCs utilizing silicon dioxide (SiO2) nanofluids with varying particle sizes (20 nm, 50 nm, and 100 nm) compared to deionized (DI) water as the heat transfer fluid (HTF). The objective is to enhance PTSC performance by improving the HTF’s thermal properties by adding SiO2 nanoparticles. SiO2 nanofluids were synthesized using the sol-gel method and characterized for thermal conductivity, viscosity, and specific heat capacity. _The novelty of this study lies in the comprehensive analysis of the effects of nanoparticle size on PTSC efficiency, which offers practical insights for optimizing solar thermal systems. Experimental setups measured PTSC thermal efficiency under varying solar irradiation and ambient temperature conditions. The results showed a significant improvement in thermal efficiency when using SiO2 nanofluids, with the 20 nm nanoparticles exhibiting the highest enhancement of approximately 26% over DI water. The 50 nm and 100 nm nanoparticles showed 21% and 17% improvements, respectively. The increased efficiency is attributed to smaller nanoparticles’ higher surface area-to-volume ratio, which enhances thermal conductivity and reduces boundary layer thickness. Additionally, thermal conductivity increases with temperature and decreases with nanoparticle size, while specific heat capacity decreases with temperature and nanoparticle size. SiO2 nanofluids, particularly those with smaller nanoparticles, significantly enhance the thermal performance of PTSCs. This study highlights the potential of nanofluids in solar thermal applications and provides a basis for further research on the long-term stability and economic viability of nanofluid-based HTFs.

KINETICS AND THERMODYNAMICS STUDIES ON OIL EXTRACTION FROM SOUTHERN KADUNA PALM KERNEL SEEDS USING SUBCRITICAL WATER EXTRACTION TECHNOLOGY

Subcritical water has the potential to be highly efficient, non-toxic and low-cost alternative extraction solvent due to its unique properties under certain conditions. In this current study, we used the process variables (extraction temperature, time and particle size) to investigate the kinetics of palm kernel oil (PKO) extraction using subcritical water as solvent by considering the power law and Elovich’s kinetic law models. The laws of thermodynamics were employed to determine the spontaneity and nature of the PKO extraction process by evaluating thermodynamic parameters such as the Gibbs free energy (ΔG), enthalpy change (ΔH) and entropy change (ΔS). The experimental result showed that the conditions for the optimum yield of PKO using subcritical water were established at 0.5 mm, 120 minutes and 493K (200 ◦C) where the highest oil yield was (49.02%). The experimental data was found to best fit the power law model compared to the Elovich’s model, as a result of its highest R2 and lowest SD and RMS values. Thermodynamics analysis showed that PKO extraction has positive enthalpy and entropy values of 7.23×10-4kJ/mol and 0.0304kJ/molK respectively, indicating an endothermic and irreversible process. The negative values of Gibbs free energy (– 12.56 to -14.99kJ/molK) indicated that the extraction process is spontaneous. Gas chromatography analysis showed that lauric acid (48.1%) appears as the predominant fatty acid in the extracted oil followed by myristic acid (16.0%) and linoleic acid (14.9%). The subcritical water technology was therefore, highly recommended for the extraction of PKO due to its high potentials as shown in the high oil yield obtained. The power law model was also recommended due to the overall comparative fitness to the experimental data while the thermodynamics specifications as verified in this work were also recommended to be used for process design of PKO extraction.

Lattice Boltzmann Modeling of Additive Manufacturing of Functionally Graded Materials.

Functionally graded materials (FGMs) show continuous variations in properties and offer unique multifunctional capabilities. This study presents a simulation of the powder bed fusion (PBF) process for FGM fabrication using a combination of Unity-based deposition and lattice Boltzmann method (LBM)-based process models. The study introduces a diffusion model that allows for the simulation of material mixtures, in particular AISI 316L austenitic steel and 18Ni maraging 300 martensitic steel. The Unity-based model simulates particle deposition with controlled distribution, incorporating variations in particle size, friction coefficient, and chamber wall rotation angles. The LBM model that simulated free-surface fluid flow, heat flow, melting, and solidification during the PBF process was extended with diffusion models for mixture fraction and concentration-dependent properties. Comparison of the results obtained in simulation with the experimental data shows that they are consistent. Future research may be connected with further verification and validation of the model, by modeling different materials. The presented model can be used for the simulation, study, modeling, and optimization of the production of functionally graded materials in PBF processes.

Impact of Soil Type and Moisture Content on Microwave-Assisted Remediation of Hydrocarbon-Contaminated Soil

Volatile and semi-volatile compounds, such as petroleum hydrocarbons and equipment lubricating oils, often contaminate soil due to accidents, posing significant ecological and health risks. Traditional soil remediation methods, such as thermal desorption and bioremediation, are time-consuming and resource-intensive, prompting researchers to explore more efficient alternatives. This study investigates the effectiveness of an in situ reactor for microwave-assisted soil remediation, specifically focusing on the impact of soil type and moisture content on pollutant removal efficiency. The reactor, designed to operate within a modified household microwave oven, provides direct microwave irradiation to the soil surface, enabling precise control of heating conditions. Experiments were conducted using soil samples of varying particle sizes and moisture levels under standardized conditions (1000 W microwave power, 2.45 GHz frequency). The results show that moisture content plays a critical role in pollutant removal efficiency, with an optimal moisture content of 10 wt % enhancing microwave absorption and energy transfer, thus improving pollutant recovery. In comparison with traditional resistive heating, microwave heating achieved a faster temperature rise and higher final temperatures, significantly improving pollutant removal efficiency in a shorter time frame. This study highlights the advantages of microwave heating, including its superior energy efficiency, faster pollutant volatilization, and the potential for optimized soil remediation in real-world applications. These findings provide valuable insights for the development of more sustainable and efficient soil remediation technologies.

Fabrication of Nano Copper Highly Conductive and Flexible Printed Electronics by Direct Ink Writing.

Nanoscale metals have emerged as crucial materials for conductive inks in printed electronics due to their unique physical and chemical properties. However, the synthesis of high-precision and highly conductive copper ink remains a challenge. Herein, a high-precision, highly conductive, and oxidation-resistant nanocopper ink was synthesized to fabricate highly conductive and flexible printed electronic devices. Copper nanoparticles with a particle size of only 8.5 nm, a controllable structure, and excellent oxidation resistance were synthesized by the alcohol phase reduction method. The conductive ink was formulated with ethylene glycol, ethanol, and isopropanolamine (IPA) as the solvent, exhibiting excellent printability and sintering reducibility. Fluid dynamics simulations were employed to investigate the influence of printing parameters on the circuit forming performance, enabling precise control over the printing process. The sintering behavior of copper nanoparticles with varying particle sizes was investigated by combining experiments with molecular dynamics (MD) simulations. Highly conductive and flexible circuits were fabricated using direct ink writing (DIW) under low-temperature sintering, exhibiting a low resistance level as low as 1.9 μΩ·cm. Moreover, the circuit demonstrated an excellent adhesion performance and bending flexibility. The developed copper ink demonstrates outstanding printing potential for applications in flexible electronics, advancing the field of flexible printing and wearable electronic devices.

Polyetheretherketone‐hydroxyapatite composite filament: A comparative analysis of the effect of micro and nano hydroxyapatite particles on extrusion and performance

AbstractThe performance of polyether‐ether‐ketone (PEEK) as an orthopedic biomaterial can be improved by bulk modification of PEEK through hydroxyapatite (HA) incorporation. In this context, we have studied the size effect of HA particles (from micro to nano) on the high‐temperature extrusion, physicochemical and biological properties of the extruded PEEK‐HA filaments. Our study showed that incorporation of HA into PEEK up to 5% w/w allows filament formation through single screw extrusion. However, a more significant temperature gradient between the hopper end and nozzle was necessary for the extrusion of nano‐HA incorporated PEEK compared to micro‐HA incorporated PEEK. The micro‐CT revealed a homogeneous dispersion of HA particles within the extruded filaments. The inclusion of nano HA powder (<200 nm) in PEEK (5%w/w) did not alter the mechanical properties of PEEK. When checked in vitro using MG‐63 cells, PnHA exhibited better cytocompatibility, as evidenced by calcein‐AM staining and MTT assay. Cellular expression of vascular endothelial growth factor and alkaline phosphatase was also found to be 2–3 fold higher for PnHA. Further, PnHA was found to be a promoter of angiogenesis when checked by tube formation assay. The results together implied that nano‐HA is more suitable than micro‐HA for improving the essential qualities of PEEK for orthopedic applications.Highlights Incorporation of HA in PEEK improves the performance of PEEK as a biomaterial. PEEK with 5% micro/nano HA can be extruded as PEEK‐HA composite filament. Variation in HA particle size (micro/nano) impacts the performance of composite. PEEK‐HA composite filament has improved angiogenic and osteoconductive properties.

Cytotoxicity and Antimicrobial Efficacy of Fe-, Co-, and Mn-Doped ZnO Nanoparticles.

Zinc oxide nanoparticles (ZnO NPs) are one of the most widely used nanoparticulate materials due to their antimicrobial properties. However, the current use of ZnO NPs is hindered by their potential cytotoxicity concerns, which are likely attributed to the generation of reactive oxygen species (ROS) and the dissolution of particles to ionic zinc. To reduce the cytotoxicity of ZnO NPs, transitional metals are introduced into ZnO lattices to modulate the ROS production and NP dissolution. However, the influence of the doping element, doping concentration, and particle size on the cytotoxicity and antimicrobial properties remains unexplored. This study presents a comprehensive investigation of a library of doped ZnO NPs to elucidate the relationship between their physicochemical properties, antimicrobial activity against Escherichia coli (E. coli), and cytotoxicity to mammalian cells. The library comprises 30 variants, incorporating three different dopant metals-iron, manganese, and cobalt-at concentrations of 0.25%, 1%, and 2%, and calcined at three temperatures (350 °C, 500 °C, and 600 °C), resulting in varied particle sizes. These ZnO NPs were prepared by low temperature co-precipitation followed by high-temperature calcination. Our results reveal that the choice of dopant elements significantly influences both antimicrobial efficacy and cytotoxicity, while dopant concentration and particle size have comparatively minor effects. High-throughput UV-visible spectroscopic analysis identified Mn- and Co-doped ZnO NPs as highly effective against E. coli under standard conditions. Compared with undoped ZnO particles, Mn- and Co-doping significantly increased the oxidative stress, and the Zn ion release from NPs was increased by Mn doping and reduced by Fe doping. The combined effects of these factors increased the cytotoxicity of Mn-doped ZnO particles. As a result, Co-doped ZnO particles, especially those with 2 wt.% doping, exhibited the most favourable balance between enhanced antibacterial activity and minimized cytotoxicity, making them promising candidates for antimicrobial applications.

Influence of Composition on the Patterns of Electrokinetic Potential of Thermosensitive N-(Isopropyl)Acrylamide Derivatives with Poly(Ethylene Glycol) Dimethacrylate and N-(2-Hydroxyethyl)Acrylamide.

The synthesis of poly(N-isopropyl acrylamide) (pNIPA)-based polymers via the surfactant-free precipitation polymerization (SFPP) method produced thermosensitive nanospheres with a range of distinctive physicochemical properties. Nano- and microparticles were generated using various initiators, significantly influencing particle characteristics, including the hydrodynamic diameter (DH), which varied from 87.7 nm to 1618.1 nm. Initiators, such as potassium persulfate and 2,2'-azobis(2-methylpropionamidine) dihydrochloride, conferred anionic and cationic functionalities, respectively, impacting the electrokinetic potential (EP) of the particles. Notably, certain particles with cationic initiators exhibited negative EP values at 18 °C, attributed to residual initiator components that affected the surface charge distribution. The presence of hydrophilic N-(2-hydroxyethyl)acrylamide (HEAA) segments also influenced solubility and phase transition behaviors, with critical dependencies on the HEAA/NIPA (N-isopropyl acrylamide) molar ratios. EP measurements taken at 18 °C and 42 °C revealed substantial differences, primarily governed by the initiator type and polymer composition. Observed variations in particle stability and size were associated with the choice of crosslinking agents and comonomer content, which affected both DH and EP in distinct ways. This study provides insights into key factors influencing colloidal stability and electrostatic interactions within thermosensitive polymer systems, underscoring their potential applications in biomedical and industrial fields.

Date Palm Waste-Derived Biochar for Improving Hydrological Properties of Sandy Soil Under Saturated and Unsaturated Conditions

Water conservation and effective irrigation management are vital for sustainable agriculture in arid regions. While organic soil amendments have been widely used to enhance water retention in sandy soils, research on the use of date palm waste-derived biochar remains limited. Thus, this study aimed to explore the innovative application of biochar produced from date palm waste, focusing on its effects on the hydrological properties of sandy soil. Biochars of varying particle sizes (0.5, 1, and 2 mm) and pyrolysis temperatures (300 °C, 450 °C, and 600 °C) were produced and their impacts were assessed under both saturated and unsaturated conditions on soil hydrological properties. The biochar was incorporated into soil columns at application rates of 0%, 1%, 3%, and 5% (w/w) within a 10 cm layer on top of 35 cm deep soil columns. The soil columns were placed vertically into water basins for saturation. Evaporation, infiltration, and saturated hydraulic conductivity were measured. The findings revealed that the application of 1%, 3%, and 5% biochar significantly increased soil water retention by 36.80%, 34.18%, and 29.66%, while cumulative evaporation decreased by 7.30%, 2.00%, and 1.35%, respectively, as compared to the control. Water retained at the end of the experiment was increased by 100.63%, 112.29%, and 101.68%, while unsaturated hydraulic conductivity decreased by 21.27%, 26.15%, and 26.17% after amending the soil with 1%, 3%, and 5% biochar, respectively, as compared to the control. The water retention ranged between 30.34 and 42.51%, 22.59 and 43.20%, and 22.48 and 38.81% for biochar produced at 300 °C, 450 °C, and 600 °C, respectively. Water infiltration rate and pore size was decreased with the increased pyrolysis temperature. Overall, the application rates of 3% and 5% with particle sizes of 1 and 0.5 mm and low pyrolysis temperature were most efficient for improving soil properties such as water retention, reducing unsaturated hydraulic conductivity, reducing the rate and volume of infiltration, and enhancing the micro-porosity reduction of sandy soils. In a nutshell, this study highlights the potential of date palm waste-derived biochar as an effective soil amendment, significantly enhancing water retention by up to 112.29% and reducing evaporation. By optimizing irrigation management in sandy soils, these findings contribute to more sustainable agricultural practices.

Deciphering Surface-Localized Structure of Nanodiamonds.

Nanomaterials, heralded as the "new materials of the 21st century" for their remarkable physical and chemical properties and broad application potential, have attracted substantial attention in recent years. Among these materials, which challenge traditional physical boundaries, nanodiamonds (NDs) are widely applied across diverse industries due to their exceptional surface multifunctionality and chemical stability. Nevertheless, atomic-level manipulation of NDs presents considerable challenges, which require detailed structural analysis to thoroughly elucidate their properties. This study utilizes density functional theory (DFT), lattice dynamics, and molecular dynamics (MD) simulations to analyze the structural and property characteristics of NDs. Fine structural analysis reveals that, despite variations in particle size, surface layer thickness remains relatively constant at approximately 3 Å. DFT methods enable computation of the surface layer to capture subtle electronic characteristics, while the internal core is analyzed via MD. Further investigation into amorphous structure control indicates that ND surface amorphous structures with a packing coefficient above 0.38 are thermodynamically stable. This study offers a novel approach to nanomaterial control in practical applications by elucidating the core-shell interactions and surface structures of NDs.

Thermoplastic Composite Hot-Melt Adhesives with Metallic Nano-Particles for Reversible Bonding Techniques Utilizing Microwave Energy.

This study investigated the creation of nano-composites using recycled LDPE and added 7.5 wt% nanofillers of Al and Fe in two varying particle sizes to be used as hot-melt adhesives for reversible bonding processes with the use of microwave technology. Reversible bonding relates to circular economy enhancement practices, like repair, refurbishment, replacement, or renovation. The physical-chemical, mechanical, and dielectric characteristics were considered to determine the impact of particle size and metal type. Through the investigation of electromagnetic radiation absorption in the composites, it was discovered that the optimal bonding technique could potentially involve a frequency of 915 MHz and a power level of 850 × 103 W/kg, resulting in an efficient process lasting 0.5 min. It was ultimately proven that the newly created hot-melt adhesive formulas can be entirely recycled and repurposed for similar bonding needs.