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A detailed understanding of the physical essence of the interaction between a femtosecond laser and its target material remains an important and challenging goal. In this paper, the thermoelastic vibration behavior of nickel films irradiated by a femtosecond laser is studied by a molecular dynamics method combined with a two-temperature model. The model fully defines the spatial distribution of laser energy, the photoelectron coupling, and the electron-lattice coupling, and elucidates the temperature and stress evolution within the nickel film under femtosecond laser irradiation. Furthermore, the whole process and the mechanism of thermoelastic vibration is revealed at the atomic level. The thermoelastic vibration is divided into two stages, including continuous expansion during the process of energy relaxation and periodic expansion and contraction after reaching thermal equilibrium. The elastic oscillation of thin films is driven by periodic changes in energy, including the energy of atomic thermal motion and collective atomic motion. The effect of pulse fluence on thermoelastic vibration is also discussed in detail to provide reasonable suggestions for limiting this effect. This study provides the theoretical foundation and a feasible method for a deeper understanding of the interaction mechanisms between femtosecond lasers and materials. [ABSTRACT FROM AUTHOR]

Compared with conventional solders, nano-silver benefits low-temperature sintering and high-temperature service, perfectly matching the high-temperature operating environment for third-generation semiconductor devices. However, the synthetic cost, complexity of the sintering process and the low connection strength limit its development. This paper describes the physical, chemical reduction and biological methods of synthesizing and compares the advantages and disadvantages of these three methods. The process parameters affecting the sintering process of silver nanoparticles (Ag NPs) are presented in a comprehensive and in-depth manner. Present methods are also introduced to improve the quality of nano-silver joints, such as the adding enhancement, the silver nanostructured films, and a trimodal-Ag paste consisting of silver particles in three sizes: nano, submicron and micron, aiming to break the limitation of the poor quality of nano-silver joints. In addition, this paper provides the first comprehensive summary of the sintering process and sintering mechanism of nano-silver, and introduces the latest results of the study of the sintering mechanism of nano-silver by using the Molecular Dynamics Simulation (MDS) technique. At the end, the advanced applications of nano-silver are shown, thus pointing out the direction for the further development and applications of nano-silver. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAP) is a naturally occurring calcium phosphate mineral that resembles human hard tissue in structure and composition. Its unique structure makes it suitable for a variety of applications such as biomedical implants, pollution control, nuclear waste management. The hexagonal structure of HAP endows it with five independent elastic constants, and a comprehensive understanding of their role and properties is essential for large scale adoption of HAP in various applications. However, the limited experimental and computational estimates currently available exhibit a wide scatter and occasional inconsistencies, and little effort has been made to quantify the influence of operating temperature on HAP elastic response. In this paper, we calculate the five elastic constants of hexagonal HAP first from Density Functional Theory (DFT)-based stress–strain relations derived using ultrasoft pseudopotential with Perdew–Burke–Ernzerho (PBE) exchange-correlation functional under generalized gradient approximation (GGA) on the 44 atom single unit cell, and then with molecular dynamics (MD)-based stress–strain relations derived from 4 × 4 × 6 unit cells using three distinct families of force fields. These force fields are differentiated by how they model the non-bonded interactions: Lennard–Jones, Born–Mayer–Huggins and Buckingham types. We conduct the MD studies in the temperature range of 10–500 K. We find DFT to slightly overestimate the unit cell volume (a known consequence of using GGA) compared to X-ray powder diffraction-based experimental values reported in the literature. The predicted elastic constants satisfy Born's criterion for mechanical stability. All potential models agree with DFT that HAP exhibits higher stiffness along c -axis. Lattice parameters are found to increase with temperature, while the elastic constants decrease. Their rate of change, however, differs based on the force field. Among the three, the force field based on Buckingham potential appears to perform the best and agrees qualitatively with DFT and experimental results. [ABSTRACT FROM AUTHOR]

An increasing number of papers propose routes to implement thermal counterparts of electronic rectification. These schemes are mainly based on combinations of crystal anharmonicity and broken mirror symmetry. With respect to graphene, proposals pivot around shape asymmetry induced by using hetero-structures of nano-patterned or defected sections of pristine graphene. Using Molecular Dynamics (MD) we show that it suffices to split a graphene nano-ribbon into two unequal strained sections using external force which leads to large asymmetry in the forward and reverse heat fluxes. We find that the corresponding rectification ratio is enhanced by up to 60%. Also, and more importantly, the polarity is controllable on-the-fly i.e. , by changing the position where the force is applied. Based upon our results we propose a thermo-electric device which obviates the complex nano-patterning and lithography required to pattern graphene every time a new rectification value or sign is sought for, opening a route to simpler fabrication and characterization of phononic phenomena in 2D materials. [ABSTRACT FROM AUTHOR]

Vitamin B1 (thiamine) plays an important role in human metabolism. It is essential for the proper growth and development of the body and has a positive effect on the functioning of the digestive, cardiovascular, and nervous systems. Additionally, it stimulates the brain and improves the psycho-emotional state. In vivo, vitamin B1 occurs in free form as thiamine or as its ester with phosphate residue(s), i.e., as mono-, di-, or triphosphate. It has been proven that supportive therapy with vitamin B1 can not only provide neuroprotection but also has a positive effect on advanced neurodegenerative diseases, such as Parkinson's disease, Alzheimer's disease, Wernicke–Korsakoff syndrome, or Huntington's disease. This paper presents studies on the effect of free thiamine (T) and thiamine pyrophosphate (TPP) on the activity of acetylcholinesterase (AChE), which is an enzyme considered to play an important role in the therapies for neurodegenerative diseases, especially Alzheimer's disease. The mechanisms of action of these compounds as potential inhibitors of AChE were evaluated using both experimental (enzymatic activity) as well as computational (molecular docking, molecular dynamics simulations, and MM-GBSA calculations) methods. The results of the current study indicate a non-competitive type of enzyme inhibition, in contrast to the previously published works suggesting a competitive one. [ABSTRACT FROM AUTHOR]

In this paper, we present a molecular dynamics study of the structural and dynamical properties of γ-valerolactone (GVL) both as a standalone solvent and in electrolyte formulations for electrochemistry applications. This study involves developing a new parameterization of a polarizable forcefield and applying it to simulate pure GVL and selected salt solutions. The forcefield was validated with experimental bulk data and quantum mechanical calculations, with excellent agreement obtained in both cases. Specifically, two 1M electrolyte solutions of lithium bis(fluorosulfonyl)imide and lithium bis(oxalate)borate in GVL were simulated, focusing on their ionic transport and highlighting ion solvation structure. Ion pairing in the electrolytes was also investigated through enhanced sampling molecular dynamics, obtaining a detailed picture of the ion dynamics in the GVL solution. [ABSTRACT FROM AUTHOR]

Shale oil reservoirs feature a considerable number of nanopores and complex minerals, and the impact of nano-pore confinement and pore types frequently poses challenges to the efficient development of shale oil. For shale oil reservoirs, CO2 flooding can effectively lower crude oil viscosity, enhance reservoir physical properties, and thereby increase recovery. In this paper, the CO2 displacement process in the nanoscale pores of shale oil was simulated through the molecular dynamic simulation method. The performance disparity of quartz and calcite slit nanopores was discussed, and the influences of nanoscale pore types and displacement rates on CO2 displacement behavior were further analyzed. The results demonstrate that the CO2 displacement processes of different inorganic pores vary. In contrast, the displacement efficiency of light oil components is higher and the transportation distance is longer. Intermolecular interaction has a remarkable effect on the displacement behavior of CO2 in nanopores. On the other hand, it is discovered that a lower displacement rate is conducive to the miscible process of alkane and CO2 and the overall displacement process of CO2. The displacement efficiency drops significantly with the increase in displacement velocity. Nevertheless, once the displacement speed is extremely high, a strong driving force can facilitate the forward movement of alkane, and the displacement efficiency will recover slightly. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) grouting materials are widely used in underground engineering rehabilitation, particularly in reinforcement and waterproofing engineering in deep-water environments. The long-term effect of complex underground environments can lead to nanochannel formation within PU, weakening its repair remediation effect. However, the permeation behavior and microscopic mechanisms of water molecules within PU nanochannels remain unclear. In this paper, a model combining PU nanochannels and water molecules was constructed, and the molecular dynamics simulations method was used to study the effects of water pressure and channel width on permeation behavior and microstructural changes. The results reveal a multi-stage, layered permeation process, with significant acceleration observed at water pressures above 3.08 MPa. Initially, water molecules accelerate but are then blocked by the energy barrier of PU nanochannels. After about 20 ps, water molecules overcome the potential barrier and enter the nanochannel, displaying a secondary acceleration effect, with the maximum permeation depth rises from 1.8 nm to 11.8 nm. As the channel width increases, the maximum permeation depth increases from 7.5 nm to 11.6 nm, with the rate of increase diminishing at larger widths. Moreover, higher water pressure and wider channels enhance the stratification effect. After permeation, a hydrophobic layer of approximately 0.5 nm thickness forms near the channel wall, with a density lower than that of the external water. The middle layer shows a density slightly higher than the external water, and the formation of hydrogen bonds between water molecules increases toward the channel center. [ABSTRACT FROM AUTHOR]

In order to eliminate the negative effects caused by traditional pavements, permeable pavements are gradually being used in road construction. In recent years, polyurethane (PU) has been used as a new binder in permeable pavement mixtures. However, compared to traditional pavement mixtures, the adhesion properties between PU and aggregate have not been systematically analyzed. In addition, no clear standards have been established for the performance testing of PU mixtures, posing significant challenges for the selection of materials and the optimization of formulations for PU mixtures. Therefore, this paper proposes new methods for evaluating the performance of PU mixtures from a microscopic point of view, aiming at evaluating the adhesion properties between PU and aggregates. In this study, a PU binder was synthesized. The adhesion properties of this PU binder with aggregate were evaluated by surface free energy measurement and molecular dynamics (MD) simulation. Finally, the effects of different environmental conditions and aggregate types on the PU–aggregate adhesion properties were investigated. The results showed that the adhesion between PU and basalt is consistently better than that with limestone, although the adhesion between PU and aggregate decreased under acidic conditions. It implies that the PU–basalt mixture has better water resistance than the PU–limestone mixture. Furthermore, the results of the surface free energy measurements and MD simulations for the evaluation of adhesion at the PU–aggregate interface showed good correlation with the macroscopic performance experiments, which can be extended to the study of the adhesion properties of other materials. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals heterostructures consist of different 2D crystals with diverse properties, constituting the cornerstone of the new generation of 2D electronic devices. Yet interfaces in heterostructures inevitably break bulk symmetry and structural continuity, resulting in delicate atomic rearrangements and novel electronic structures. In this paper, we predict that 2D interfaces undergo "spontaneous curvature", which means when two flat 2D layers approach each other, they inevitably experience out-of-plane curvature. Based on deep-learning-assisted large-scale molecular dynamics simulations, we observe significant out-of-plane displacements up to 3.8 Å in graphene/BN bilayers induced by curvature, producing a stable hexagonal moiré pattern, which agrees well with experimentally observations. Additionally, the out-of-plane flexibility of 2D crystals enables the propagation of curvature throughout the system, thereby influencing the mechanical properties of the heterostructure. These findings offer fundamental insights into the atomic structure in 2D van der Waals heterostructures and pave the way for their applications in devices. Lattice mismatch in 2D van der Waals heterostructures induces lattice reconstruction to optimize the stacking. Here, the authors show how this introduces curving of different heterobilayers from deep-learning-assisted molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

Background: Artificial sweeteners (AS) have been widely utilized in the food, beverage, and pharmaceutical industries for decades. While numerous publications have suggested a potential link between AS and diseases, particularly cancer, controversy still surrounds this issue. This study aims to investigate the association between AS consumption and cancer risk. Methods: Targets associated with commonly used AS were screened and validated using databases such as CTD, STITCH, Super-PRED, Swiss Target Prediction, SEA, PharmMapper, and GalaxySagittarius. Cancer-related targets were sourced from GeneCards, OMIM, and TTD databases. AS-cancer targets were identified through the intersection of these datasets. A network visualization ('AS-targets-cancer') was constructed using Cytoscape 3.9.0. Protein–protein interaction analysis was conducted using the STRING database to identify significant AS-cancer targets. GO and KEGG enrichment analyses were performed using the DAVID database. Core targets were identified from significant targets and genes involved in the 'Pathways in cancer' (map05200). Molecular docking and dynamics simulations were employed to verify interactions between AS and target proteins. Pan-cancer and univariate Cox regression analyses of core targets across 33 cancer types were conducted using GEPIA 2 and SangerBox, respectively. Gene chip datasets (GSE53757 for KIRC, GSE21354 for LGG, GSE42568 for BRCA, and GSE46602 for PRAD) were retrieved from the GEO database, while transcriptome and overall survival data were obtained from TCGA. Data normalization and identification of differentially expressed genes (DEGs) were performed on these datasets using R (version 4.3.2). Gene Set Enrichment Analysis (GSEA) was employed to identify critical pathways in the gene expression profiles between normal and cancer groups. A cancer risk prognostic model was constructed for key targets to further elucidate their significance in cancer initiation and progression. Finally, the HPA database was utilized to investigate variations in the expression of key AS-cancer target proteins across KIRC, LGG, BRCA, PRAD, and normal tissues. Results: Seven commonly used AS (Aspartame, Acesulfame, Sucralose, NHDC, Cyclamate, Neotame, and Saccharin) were selected for study. A total of 368 AS-cancer intersection targets were identified, with 48 notable AS-cancer targets, including TP53, EGFR, SRC, PIK3R1, and EP300, retrieved. GO biological process analysis indicated that these targets are involved in the regulation of apoptosis, gene expression, and cell proliferation. Thirty-five core targets were identified from the intersection of the 48 significant AS-cancer targets and genes in the 'Pathways in cancer' (map05200). KEGG enrichment analysis of these core targets revealed associations with several cancer types and the PI3K-Akt signaling pathway. Molecular docking and dynamics simulations confirmed interactions between AS and these core targets. HSP90AA1 was found to be highly expressed across the 33 cancer types, while EGF showed the opposite trend. Univariate Cox regression analysis demonstrated strong associations of core targets with KIRC, LGG, BRCA, and PRAD. DEGs of AS-cancer core targets across these four cancers were analyzed. GSEA revealed upregulated and downregulated pathways enriched in KIRC, LGG, BRCA, and PRAD. Cancer risk prognostic models were constructed to elucidate the significant roles of key targets in cancer initiation and progression. Finally, the HPA database confirmed the crucial function of these targets in KIRC, LGG, BRCA, and PRAD. Conclusion: This study integrated data mining, machine learning, network toxicology, molecular docking, molecular dynamics simulations, and clinical sample analysis to demonstrate that AS increases the risk of kidney cancer, low-grade glioma, breast cancer, and prostate cancer through multiple targets and signaling pathways. This paper provides a valuable reference for the safety assessment and cancer risk evaluation of food additives. It urges food safety regulatory agencies to strengthen oversight and encourages the public to reduce consumption of foods and beverages containing artificial sweeteners and other additives. [ABSTRACT FROM AUTHOR]

Nanodroplet collisions with solid surfaces can occur in various applications of electrospray technology. In electrospray propulsion, the deposition and splashing of droplets from the beam onto surfaces are critical to the performance and lifetime of the electrospray thrusters, but little is known about the underlying mechanisms. Therefore, this paper developed a detailed molecular dynamics model to simulate the collisions of an ionic liquid nanodroplet under varying electric fields and charges. The results show that under a 1000 V acceleration voltage, the droplet dissociates into cations and anions after a high-speed collision with the surface. The deposition characteristics are influenced by the oscillation between cations and anions and the applied electric field. When the electric field strength is low, the oscillation between ions leads to easier deposition of cations, causing neutral droplets to deposit a small amount of positive charge after the collision. Only negatively charged droplets may deposit a neutral or negative charge. When the electric field strength is high, it separates the cations and anions, resulting in significant charge deposition due to the imbalance of ion quantities on the surface. Furthermore, as the charge of the droplet increases, the deposition rate fluctuates, which is related to the momentum exchange caused by the oscillation between ions. This paper reveals the collision mechanism of ionic liquid nanodroplets in an electrospray environment, which may contribute to the further development of droplet–wall collision models in electrospray propulsion or deposition. [ABSTRACT FROM AUTHOR]

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HOP–graphene is a graphene structural derivative consisting of 5-, 6-, and 8-membered carbon rings with distinctive electrical properties. This paper presents a systematic investigation of the effects of varying sizes, strain rates, temperatures, and defects on the mechanical properties of HOP–graphene, utilizing molecular dynamics simulations. The results revealed that Young's modulus of HOP–graphene in the armchair direction is 21.5% higher than that in the zigzag direction, indicating that it exhibits greater rigidity in the former direction. The reliability of the tensile simulations was contingent upon the size and strain rate. An increase in temperature from 100 K to 900 K resulted in a decrease in Young's modulus by 7.8% and 2.9% for stretching along the armchair and zigzag directions, respectively. An increase in the concentration of introduced void defects from 0% to 3% resulted in a decrease in Young's modulus by 24.7% and 23.1% for stretching along the armchair and zigzag directions, respectively. An increase in the length of rectangular crack defects from 0 nm to 4 nm resulted in a decrease in Young's modulus for stretching along the armchair and zigzag directions by 6.7% and 5.7%, respectively. Similarly, an increase in the diameter of the circular hole defect from 0 nm to 4 nm resulted in a decrease in Young's modulus along both the armchair and zigzag directions, with a corresponding reduction of 11.0% and 10.4%, respectively. At the late stage of tensile fracture along the zigzag direction, HOP–graphene undergoes a transformation to an amorphous state under tensile stress. Our results might contribute to a more comprehensive understanding of the mechanical properties of HOP–graphene under different test conditions, helping to land it in potential practical applications. [ABSTRACT FROM AUTHOR]

Feruloyl esterases (FAEs) play critical roles in industrial applications such as food processing, pharmaceuticals, and paper production by breaking down plant cell walls and releasing ferulic acid. However, most bacterial FAEs function optimally in acidic environments, limiting their use in alkaline industrial processes. Additionally, FAEs with alkaline activity often lack the thermal stability required for demanding industrial conditions. In this study, an alkaline feruloyl esterase, PhFAE, from Pandoraea horticolens was identified that exhibits high catalytic activity but suffers from thermal instability, restricting its broader industrial applications. To address this limitation, molecular dynamics simulations were used to analyze enzyme stability, and FireProt, an automated computational tool, was employed to design stabilizing mutations. The engineered S155F mutant demonstrated a 7.8-fold increase in half-life at 60 °C and a 1.72-fold improvement in catalytic efficiency (Kcat/Km), corresponding to 680% and 72% enhancements, respectively, compared to the wild-type enzyme. Molecular docking and dynamics simulations revealed that these enhancements were likely due to increased hydrophobic interactions and altered surface charge, which stabilized the enzyme's structure. This study provides an effective strategy for improving the functional properties of FAEs and other industrial enzymes, broadening their applicability in diverse industrial processes. [ABSTRACT FROM AUTHOR]

Purpose: The present study aims to design and simulate various types of deoxyribonucleic acid (DNA) origami-based nanopores and explore their stability under different temperatures and constraints. To create DNA origami nanopores, both one-layer and two-layer structures can be utilized. Design/methodology/approach: One of the key applications of DNA origami structures involves the creation of nanopores, which have garnered significant interest for their diverse applications across multiple scientific disciplines. DNA origami nanopores can be studied individually and in combination with other structures. The structural stability of these nanopores across various temperature conditions is crucial for enabling the passage of diverse payloads. Findings: Comparing these DNA origami structures can provide valuable insights into the performance of these nanopores under different conditions. The results indicate that two-layer nanopores exhibit better structural stability under various temperatures compared to one-layer nanopores. Additionally, small structural changes in two-layer nanopores enable them to maintain stability even at high temperatures. Originality/value: In this paper, various DNA origami-based nanopores were designed and simulated, focusing specifically on one-layer and two-layer configurations. The two-layer nanopore consistently exhibited superior stability across both free and restrained scenarios, undergoing fewer structural changes compared to the one-layer nanopore. As temperatures increased, the two-layer nanopore remained less susceptible to deformation, maintaining closer to its original shape. Moreover, in the free scenario, the geometric shape of the two-layer nanopore demonstrated fewer variations than the one-layer nanopore. [ABSTRACT FROM AUTHOR]

The overuse of antibiotics has led to Staphylococcus aureus developing resistance to conventional antibiotics, resulting in methicillin-resistant Staphylococcus aureus (MRSA), which poses a major threat to global morbidity and mortality. DNA gyrase exerts antibacterial effects by obstructing bacterial DNA translocation, leading to DNA fragmentation, which is essential for bacterial viability. Here, we present the design and synthesis of a series of hybrid compounds with previously known antibacterial sulfonamide moieties attached to a desfluoroquinolone scaffold. Sixteen desfluoroquinolone compounds containing a sulfonamide structure were synthesized by active substructure splicing, and these compounds were then subjected to computational simulation analysis, including drug-like analysis, molecular docking, and MMGBSA simulation. The results indicated that the synthesized molecules displayed satisfactory drug-likeness and stable binding modes with DNA gyrase, proving their potential as anti-MRSA agents. Based on the MMGBSA binding affinity values, the top four hit compounds (X01, X05, X12, and X14) were identified and subjected to 100 ns molecular dynamics simulations. The dynamics of the protein–ligand complexes were analyzed, confirming the results of the molecular docking and MMGBSA analysis studies. Further examination of the free energy landscape information validated the potential of desfluoroquinolone–sulfonamide hybrids as novel anti-MRSA agents. [ABSTRACT FROM AUTHOR]

GluN2B-containing NMDARs are related to neurodegenerative diseases, making the GluN2B-selective antagonist a promising drug candidate. Although several GluN2B antagonists have been developed, none have been approved for the market. Ifenprodil was the first potent GluN2B-selective antagonist, and its therapeutic use is limited due to its activity on serotonergic and adrenergic receptors. We provide a comprehensive analysis of GluN2B homologous proteins and their co-crystallized ligands using computational methods, including molecular docking, DFT calculations and molecular dynamics simulations here. This study identifies key binding modes of GluN2B antagonists, focusing on two pharmacophore models: the groups of Ifenprodil and EVT-101. It also elucidates the structure of GluN2B's V-type binding pocket and deep binding sites, identifying key residues that may influence its activity. These findings are crucial for the rational design of GluN2B antagonists. [ABSTRACT FROM AUTHOR]

Traditional phenolic separation processes produce a large amount of wastewater and high neutral oil entrainment. This work used the COSMO model to predict the separation performance of deep eutectic solvents (DESs) for m-cresol (MCR) and identified a potential extractant EmimCl : MCR (1 : 0.4) DES and its liquid phase operating window. Partial MCR in direct coal liquefaction oil and EmimCl form a DES extractant and can be recycled. The density, viscosity and thermal stability of the extractant were determined experimentally, and the effect of experimental conditions on its separation performance was explored. The structure–activity relationship was explored through visualization of quantum chemistry and molecular dynamics simulation. The in situ DES extraction method and multi-stage flash evaporation combined with the distillation process could effectively remove neutral oil and reduce energy consumption as well as obtain 99.9% MCR product. The total annual cost of the new process was 38.8% lower than that of the traditional extractive distillation process. [ABSTRACT FROM AUTHOR]

In this work, ε-CL-20 crystals with high sphericity, low sensitivity, and high true density were prepared in binary and ternary solvents using solvent–antisolvent recrystallization. The influence mechanisms of temperature, solvent type and solvent composition on crystal morphology were investigated through molecular dynamics simulations with modified attachment energy model. The results reveal that the crystals obtained in the ethyl acetate + chlorobenzene system at 313.15 K have the highest sphericity of 0.8630. The increase in temperature causes the crystals to become sharper. The crystals in ternary solvents retain morphological characteristics of those in the corresponding binary systems and the sphericities are between the two. In ternary systems, hydrogen bonding interactions are affected by the two antisolvents together, and van der Waals and electrostatic interactions can be influenced either by the combined effects of two antisolvents or predominantly by a single antisolvent. It is feasible to adjust interactions by changing growth environments. The temperature, solvent type and solvent composition can affect the diffusion behaviors of solvent molecules and the antisolvent molecules do not affect their mutual diffusion behaviors. This work provides valuable information for the design and optimization of the preparation process of spherical ε-CL-20 crystals. [ABSTRACT FROM AUTHOR]

Emulsion gels (emulgels) have emerged as cost-effective and versatile platforms in formulation engineering. In this study, we introduce Attractive Pickering Emulgels (APEGs), stabilized by the synergistic action of two oppositely charged green nanoparticles, e.g., chitin nanofibers (ChNF) and cellulose nanocrystals (CNC). The CNC, featuring anionic sulfate half-ester groups, and the cationic ChNF, possessing amine groups, form adhesive bridging networks within the continuous aqueous phase, effectively inhibiting oil droplet coalescence. This network supports micro-clustering, significantly increasing the effective droplet volume fraction by entrapping substantial amounts of the continuous phase. Consequently, the emulgels demonstrate a robust viscoelastic response and effectively modulate lipid digestibility, as evidenced by a 30% reduction in free fatty acid (FFA) release at high oil fractions (70 wt%) during in vitro digestion. The stabilization mechanism relies on noncovalent interactions and nanoparticle coassembly, validated through quartz crystal microgravimetry and molecular dynamics simulations. APEGs present significant potential for advancing sustainable nanotechnologies in pharmaceutical, food, and health formulations. [ABSTRACT FROM AUTHOR]

Ammonium dinitramide (ADN) is highly hygroscopic which poses significant challenges in its practical applications. Consequently, mitigating this hygroscopic nature has been a primary focus in the research and development of ADN. This study investigated the properties of the ADN/3-amino-5-nitro-1,2,4-triazole (ANTA) cocrystal using density functional theory, molecular dynamics, and Monte Carlo methods. The research involved analyzing binding energies, radial distribution functions, and molecular interaction energies, predicting the crystallographic properties of the cocrystal, and theoretically assessing the hygroscopicity of ADN, stability and detonation properties. The results indicated that the cocrystal achieved relative stability at a 1 : 1 molar ratio of ADN to ANTA, driven by favorable conditions for cocrystal formation. The primary forces facilitating this cocrystal formation were hydrogen bonds and van der Waals interactions. The predicted space group for the cocrystal was P1¯, with a calculated crystal density of 1.8353 g cm−3. Additionally, the cocrystal demonstrated a calculated saturated moisture absorption rate of 3.67%, which contrasted significantly with the 18.12% absorption rate observed for pure ADN. The cohesive energy density and trigger bond length indicated that the stability of the ADN/ANTA cocrystal was higher than that of ADN. Theoretical calculations indicated that the detonation performance of the cocrystal is close to that of the pure component ADN, suggesting that the ADN/ANTA cocrystal is a new type of high-energy material with low hygroscopicity. [ABSTRACT FROM AUTHOR]

The key problem for the long-term operation of the satellite in ultra-low Earth orbits (ULEO) and its safety is to provide the propulsion system with a sufficient amount of working fluid. Gas from the atmosphere can be used as the working fluid, for which the satellite is equipped with an air intake. In this paper, the problem of rarefied gas flow in such an air intake in ultra-low Earth orbit (140 km) was solved. Using the method of event-driven molecular dynamics (EDMD), we studied how the narrowing of the effective aerodynamic cross-section after the air intake (in the ionization chamber) can affect the compression ratio and the flow field. It was shown that the flow field in the air intake depends significantly on the geometry of the subsequent sections of the device, therefore it is incorrect to model the flow in the air intake separately from the rest of the internal tract of the propulsion system, as it was done in the literature earlier. • The rarefied gas flow inside the satellite air intake in ultra-low Earth orbit (140 km) was studied. • Flow field in the air intake depends significantly on the geometry of the subsequent sections of the device. • Partial permeability of the backplate qualitatively changes the dependence of the compression ratio on the channel length. • With a partially permeable backplate the dependence of the compression ratio on the channel length is not monotonic. [ABSTRACT FROM AUTHOR]

AbstractIn this paper, we have analyzed biodesulfurization of dibenzothiophene (DBT) and 4,6-dibenzothiophene (4,6-DMDBT) by 4S metabolic pathway using molecular simulations. Docking analysis revealed lower binding energies and inhibition constants (Ki) for 4,6-DMDBT and its metabolic intermediates with DSZ enzymes than DBT and its intermediates. The complexes of substrate and its metabolites with DSZ enzymes had higher stability for 4,6-DMDBT than DBT owing to lower RMSF values than apoprotein. The docking analysis revealed affinity of the inhibitors HBPS and HBP (for DBT) and DMHBPS and DMHBP (for 4,6-DMDBT) toward DSZ enzyme due to negative binding energies. Molecular dynamics simulations showed stability of several enzyme–inhibitor complexes. The inhibitory effect of DMHBPS on DSZC enzyme (Ki = 1.53 µM) and DMHBP on DSZB enzyme (Ki = 3.87 µM) was most marked. The inhibitory effect of HBP on DSZC and DSZB enzymes was moderate due to Ki of 6.36 and 7.93 µM, respectively. The inhibition effect of DMHBP on the DSZA enzyme was insignificant due to high Ki of 53.6 µM. In summary, higher stability of enzyme–substrate complexes and strong inhibition by DMHBPS and DMHBP (due to very low Ki) contribute to slower biodesulfurization of 4,6-DMDBT as compared to DBT. [ABSTRACT FROM AUTHOR]