How do foragers use nonlocal information? A novel modeling framework.

Targeted design of polyurethane modified asphalt based on Click reaction: Application for enhancing interfacial bonding properties of ultra-thin overlays

Research on the interface adsorption and emulsion properties of microwave cold plasma oxidized modified rice bran protein-phloridzin binary complex.

The aim of this study was to gain detailed insights into how different plasticizers influence the permeability of isolated hydroxypropyl methyl cellulose phthalate (HPMC-P) films. Since the migration of plasticizers from film coatings may critically affect their functionality, it is essential to monitor the impact of their leaching on the associated film properties. In this work, the leaching behavior of plasticizers from isolated HPMC-P films was estimated using their thermal properties by modulated temperature differential scanning calorimetry (MT-DSC) at varying plasticizer concentrations. The films plasticized with acetyl triethyl citrate (ATEC) and dibutyl sebacate (DBS) exhibited lower permeability compared to those plasticized with polyethylene glycol 400 (PEG 400). This reduced permeability can be attributed to the slower leaching rates of ATEC and DBS and to the persistent hydrophobic character that they impart to the films, even after prolonged aqueous exposure. In contrast, films plasticized with PEG 400 demonstrated the highest permeability because of the hydrophilicity induced in the polymeric films. However, a subsequent decline in their diffusion rate was observed once PEG 400 had leached out of the films. Furthermore, the correlation between leaching behavior and flux profiles provided an understanding of the influence of plasticizer on film permeability based on their polarity. Moreover, saturation in plasticization efficiency was noted with DBS-based films at higher plasticizer concentrations (greater than 10% w/w). Overall, our study highlights the importance of selecting appropriate plasticizers for the development of polymer films and provides insights into tailoring film permeability and drug release kinetics.

Janus nanoparticles (JNPs), which typically possess two distinct surfaces with differing physicochemical properties, exhibit more complex diffusion behavior than homogeneous nanoparticles due to their inherent asymmetry and anisotropy. A detailed understanding of their diffusion mechanisms is crucial for the rational design of functional nanomaterials such as nanocarriers for drug delivery and nanomachines. In this study, we employed coarse-grained molecular dynamics (CGMD) simulations to investigate the diffusion mechanisms of JNPs within polymer cross-linked networks of varying stiffness. Our simulations reveal that the mean square displacement (MSD) of all JNPs displays a characteristic crossover from short-time ballistic diffusion to long-time normal diffusion. The translational diffusion rates of JNPs decrease with increasing network stiffness. Furthermore, greater asymmetry in the interaction strengths between the two sides of the JNPs and the network enhances anisotropic diffusion. Dynamical heterogeneity of JNPs is further quantified using non-Gaussian parameters and van Hove correlation functions, which reveal various diffusion behaviors of the two JNP sides. Rotational diffusion is suppressed as the disparity in interactions between the two JNP sides and the network increases, while network stiffness regulates rotation depending on interaction strength. Our findings provide valuable insights into the dynamics of nanoparticles at the microscopic scale, offering theoretical guidance for the design of advanced nanomaterials.

ConspectusThe term "intermetallic" refers to a new metallic structure generated by the formation of intermetallic bonds of two or more different constituting metals. In solid-state synthesis, a very high temperature and a long duration are required to address the challenge of breaking the stable homometallic bonds and generating heterometallic bonds with the periodic diffusion of all metals forming the new compound. In nanoparticle synthesis via solution-phase methods, different atoms experience competition between the rate of reduction and diffusion, which majorly controls the formation of ordered and disordered compounds between two different metals. Intermetallic compounds (IMs) provide a unique combination of thermodynamic stability, long-range atomic ordering, heteroatomic surfaces, and electronically tunable frameworks, making them highly active and versatile for electrocatalysis. In this context, Pd2Ge stands out as a chemically intriguing intermetallic template for generating highly stable and efficient electrocatalysts. In this Account, we summarize the multiyear research of our group establishing Pd2Ge as a model platform for understanding how elemental diffusion, site-specific substitution, active interface generation, and electronic structure tuning can transform a single ordered intermetallic into a multifunctional electrocatalyst family. We showed that the solution-phase synthesis of Pd2Ge nanoparticles is achievable through careful control of the reduction kinetics and diffusion pathways, despite the significant reduction potential mismatch between Pd2+ and Ge4+. Our approach achieves the simultaneous coreduction of Pd2+ and Ge4+ precursors, effectively suppressing GeO2 formation and enabling the clean evolution of the Pd2Ge phase. After overcoming the challenge of binary intermetallic synthesis, a major challenge in intermetallic chemistry is the controlled incorporation of a third metal without disrupting the long-range order; this is governed by the reduction potential, atomic-size matching, orbital-overlap, site-preference energetics, and diffusion barriers. We demonstrate that the Pd sites in Pd2Ge can accommodate Ni, Co, Pt, and Cu through element-specific diffusion and reduction kinetics, enabling substitution up to a variable diffusion limit while preserving the ordered framework. This provides an atomic-level example for experimentally probing multimetal diffusion and lattice accommodation in a stable intermetallic matrix. Site-selective substitution has been proven by powder X-ray diffraction, high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), and density functional theory (DFT). The exact charge transfer mechanism after different element substitution has been evidenced via XPS and XAS. Our group has explored the electrochemical properties of different metal-substituted Pd2Ge in the ethanol oxidation reaction (EOR), oxygen reduction reaction (ORR), formaldehyde oxidation reaction (FAOR), and oxygen evolution reaction (OER). The exact reaction mechanism and the active site determination of this intermetallic for these reactions have been exhaustively determined via different operando spectroscopic and analytical techniques and DFT calculations. This Account gives a broad overview and a guideline about the intermetallic generation and full exploration of a stable intermetallic and how fine-tuning of the intermetallic gives rise to different electrochemical superiorities. Collectively, this Account presents the first integrated exploration of Pd2Ge as a robust and electronically programmable intermetallic, showing how kinetic control, thermodynamic driving forces, and site-selective multimetal diffusion can be leveraged to design high-performance electrocatalysts across diverse reaction environments.

The movement of a species from the bulk to the electrode surface is a fundamental process vital to many aspects of electrochemistry, including sensing, energy storage, and metal electrodeposition. For diffusion-controlled processes, several well-accepted methods to determine the rate of diffusion are available for conventional solvents; however, in more complex solvents such as ionic liquids (ILs), it is still unclear whether the same methods provide accurate measurements. In this work, we evaluated the accuracy of four electrochemical methods, namely, the Randles-Ševčík equation, the Cottrell equation, the Shoup and Szabo approximation, and the Levich equation, to determine the diffusion coefficient of ferrocene in two widely used ILs, using various working electrodes. The results show that the Randles-Ševčík equation yields reliable and accurate values on a glassy carbon (GC) electrode but lower than expected diffusion coefficients on Pt thin-film electrodes (TFEs). However, the Shoup and Szabo approximation was found to provide accurate values at a Pt micro disk electrode. The Levich method provided highly accurate diffusion coefficients for the two ILs tested; however, bubble formation prevented the diffusion coefficients from being measured in ILs with higher viscosities. The Cottrell equation was shown to generate inaccurate values, which may be due to a combination of slow rearrangement of the ions in the double layer and uncompensated ohmic resistance, leading to inflated currents after a large potential step. From these findings, it is suggested that multiple techniques should be used to confirm diffusion coefficient values in ILs, with the viscosity of the IL and the electrode material considered when choosing the best methods.

The adsorption interaction of heavy components at a mineral surface can reduce the flowability of shale oil and decrease the recovery of shale oil. In this work, the heavy component resin was separated from crude oil, and the adsorption and aggregation interactions at shale Illite surfaces were systematically studied from experimental and theoretical insights. Thermodynamic results indicated the Redlich-Peterson model (R2 = 0.990) with the maximum adsorption amount of qm = 6.19 mg/g, reflecting a composite of monolayer resin adsorption and Illite surface heterogeneity. Kinetic results indicated the pseudo-second-order model with the maximum adsorption rate of 31.48 h-1, reflecting a chemical domination of resin interaction at the Illite surface. With 170-times increasement for diffusion rate (kdif) but only 30-times increasement for aggregation rate (kagg), the 'fast diffusion-slow aggregation' processes were also analyzed for low and high resin concentration stages on the Illite surface. For a theoretical calculation, density functional theory elucidated the 'lying-down' configuration of molecular resin with interaction energy of -1.68 eV. A molecular dynamic simulation obtained the binding energy results of Ebin = -113.31 ∼ -1571.71 kcal/mol for 1-20 resin molecules. As a result, the interaction forces were deduced by combining the experimental and theoretical results, including hydrogen bonding (resin H-Illite O), cation-π interactions (resin aromatic structure-Illite K+), electrostatic adsorption (resin S-Illite K+), and coordination interaction (resin S-Illite Al, Si). The additional π-π interactions were produced between resin molecules for high resin concentration interaction. This work can clarify the microscopic interactions of heavy components at the surface of shale reservoir, which can effectively reveal the occurrence pattern of shale oil and improve oil recovery.

Myocardial reactive interstitial fibrosis (RIF) is a common feature in heart failure (HF) and is associated with changes in the structure and function of the heart. The impact of interstitial space enlargement and accumulation of interstitial collagen on oxygen transport from capillaries to cardiomyocytes during RIF is not fully understood. To address this issue, we developed a histology-image-based computer modeling approach to estimate the spatial profile of pO2 in tissue samples from the myocardium of healthy dogs and dogs with HF. The analysis shows that both interstitial space enlargement and RIF significantly limit tissue oxygenation, as evidenced by a ~ 47% lower pO2 in cardiomyocytes from HF dogs compared to normal dogs. Tissue hypoxia is primarily driven by the enlargement of interstitial space for severe RIF. The reduction in tissue pO2 for mild and moderate RIF, however, is primarily driven by the fibrosis-related functional changesin the oxygen diffusivity and maximum oxygen consumption rates. Multivariate linear regression shows cardiomyocyte pO2 significantly drops with interstitial area fraction (IAF) and rises with capillary area fraction (CAF) (R2 = 0.761, p = 0.003). Our analysis suggests the strong performance of the CAF/IAF ratio in predicting tissue oxygenation (r = 0.91, R2 = 0.824, p = 0.0001) through the coupling of interstitial expansion-impaired diffusion with reduced microvascular oxygen supply per tissue volume. These findings provide quantitative evidence that interstitial space enlargement and RIF substantially affect O2 transport from capillaries to cardiomyocytes in HF that could lead to significant regional tissue hypoxia.

Glymphatic system dysfunction in obstructive sleep apnea with mild cognitive impairment evidenced by DTI-ALPS.

Messenger ribonucleic acid (mRNA) therapeutics produced by in vitro transcription must be purified to remove residual enzymes and free nucleotides. This study examines the use of high-performance countercurrent membrane purification (HPCMP) for the purification of mRNA therapeutics based on differences in the rate of diffusion across semipermeable polyethersulfone hollow fiber membranes. Experiments were performed using two model mRNA constructs using cytosine triphosphates (CTPs) and Proteinase K as model impurities. HPCMP achieved 99.7% removal of CTPs using a residence time of 60 min with no measurable loss of mRNA. Proteinase K removal by HPCMP was reduced in the presence of mRNA due to complexation between the positively charged protein and the negatively charged mRNA, an effect that was independently confirmed by dynamic light scattering and stirred cell diafiltration experiments. The HPCMP process could be operated continuously for more than 24 h without membrane fouling with stable mRNA yield (> 97%) and Proteinase K removal (> 94%). These results clearly demonstrate the feasibility of using HPCMP for continuous purification of mRNA therapeutics.

Controlling catalyst microenvironments using proton shuttles and hydrogen bond donors in the secondary coordination sphere is a promising approach for developing catalysts that can affect multiproton and multielectron transfer processes. In this context, three palladium calixpyrrole complexes with pendent amine (1), amide (2), and carbamate (3) groups were examined as electrocatalysts for the hydrogen evolution reaction (HER). Building on prior studies showing that the palladium complexes generated catalytically active heterogeneous HER catalysts in the presence of p-toluenesulfonic acid monohydrate, 1-3 were evaluated using the significantly milder proton source anilinium tetrafluoroborate. The active catalytic species for all three systems was found to be solution-based, and kinetic analysis uncovered a first-order dependence on acid, as well as large H/D kinetic isotope effect values, which were consistent with proton-coupled electron transfer being rate-limiting. The calixpyrrole complexes displayed exceptional activity, achieving kobs and turnover frequency values of 4.65 × 106 s-1, 4.19 × 106 s-1, and 3.09 × 106 s-1 for 1, 2, and 3, respectively. These catalytic activities and rate constants approached the diffusion rate limit and ranked among the fastest HER catalysts to date.

Alkali metal post-deposition treatments (PDTs) have played a pivotal role in the development of high-efficiency Cu(In,Ga)Se2 thin film solar cells. The PDTs impact the near-surface region of the absorbers, the grain boundaries, and the bulk. Since Cu(In,Ga)Se2 solar cells are polycrystalline, the investigations turn out to be very challenging as each grain/grain boundary is affected slightly differently by the PDTs. Therefore, we synthesized Cu(In,Ga)Se2 absorbers on microcrystalline GaAs substrates to form millimeter-sized epitaxial domains with well-defined grain boundaries. This model system allows us to study the same surface orientation and grain boundary before and after PDTs. We find strong preferential (112) facets and Cu depletion on the surface, with the grain boundaries exhibiting very similar Cu-depleted compositions. After K deposition and annealing, Cu is pushed into the absorber, leaving a K-rich compound at the near-surface. Furthermore, we find different diffusion rates of K through the grain interior and via the grain boundaries. The exchange of Cu with K at the surface also occurs at the grain boundaries as measured with atom probe tomography. High-resolution KPFM measurements performed on the same grain boundary before and after PDT treatment show almost negligible grain boundary band bending. Cu-depleted K-rich area at the surface and grain boundaries exhibit very similar compositions, which gives rise to small band bending values. Our results give an unprecedented view of the mechanisms that occur at the surface, grain boundaries, and the bulk of CIGSe solar cells, paving the way to further develop the materials and improve the power conversion efficiency.

Evaluating the relationship between crystal structures of V and hydrogen diffusion to extract key features is important for understanding the relationship between hydrogen diffusion behavior and crystal structure in metals. We applied an image fusion method to surface image datasets of the vanadium alloy (a single-phase bcc V-10mol% Fe alloy) sample, obtained through different measurement methods, such as optical microscopy, scanning electron microscopy/energy-dispersive X-rays, and electron backscatter diffraction, to construct a multimodal dataset comprising hydrogen distribution and crystallographic orientation image data. The analysis of fused multimodal data by two unsupervised learning methods, such as principal component analysis and multivariate curve resolution, revealed that the hydrogen diffusion behavior differed depending on the crystallographic orientation. For example, grains oriented along the [111] and [101] directions exhibit greater hydrogen diffusion behavior than those oriented along the [001] direction. This trend was consistently observed across various analysis methods, but not when analyzed individually. In addition, it was also suggested that the shift from a pure orientation or the presence of other orientations changes the hydrogen diffusion behavior. Through multimodal data analysis of vanadium alloys, key characteristics of crystal orientation that affect hydrogen diffusion rate were extracted.

In-situ product recovery in microfluidic bioreactors.

Fine-particle loss in earth-rock dams can induce abnormal grout diffusion during rehabilitation. To address this issue, we investigated the influence of fine particle content on grouting efficiency in coarse-grained materials. Using transparent soil technology, coarse-grained materials were simulated with fused quartz sand and a refractive-index-matched pore fluid (n = 1.4585). Dyed epoxy resin was used as a cement grout analog. Constant-pressure grouting tests (40 kPa) were performed on three test conditions representing no fine-particle loss, partial fine-pareicle loss, and complete fine-particle loss. The grout diffusion process was visualized and quantified using Particle Image Velocimetry (PIV). The results reveal that fine particle content critically controls grout diffusion patterns and rates. (1) Excessive fines cause pore clogging, resulting in grout upwelling, surface seepage, and limited diffusion, forming locally consolidated masses with blocky bonding. (2) An appropriate fine particle content enables uniform spherical diffusion, creating an optimized structure characterized by point bonding of large particles and small-pore filling. (3) The absence of fines leads to gravity-dominated rapid settlement with weak horizontal diffusion, leaving only surface-coated particles. This study elucidates the coupled mechanisms of fine-particle migration, clogging, and grout diffusion, providing an experimental basis for optimizing permeation grouting in coarse aggregates.

The principles of employing antimicrobial compounds in active packaging: Mechanisms, applications, and future directions

For many decades the existence of strict aerobic bacteria was part of every textbook. However, considering habitats like soils or surfaces, many of these microorganisms are exposed to drastic changes in oxygen tension. A simple rain shower can change oxygen diffusion rates by a factor of 10.000. Thus, for many of the so-called strict aerobic bacteria, anaerobic growth and survival strategies were discovered, mainly relying on the use of alternative electron acceptors to oxygen, redox-active metabolites, or fermentation processes generating ATP at the substrate level. Survival without growth was recognized as an important lifestyle of bacteria. With the increasing availability of genome data, many highly diverse growth and survival strategies have become apparent in bacteria. But the overall picture is far from complete. Only recently, a novel puzzle piece of the anaerobic survival strategy of the opportunistic pathogen and model bacterium Pseudomonas aeruginosa in the absence of alternative electron acceptors was elucidated. It relies on the re-wiring of carbon flux away from the Entner-Doudoroff pathway towards the pentose-phosphate pathway and use of a phosphoketolase to allow for metabolic flux while preventing nonproductive NADH formation under these fermentation conditions and for ATP generation via acetate kinase.

Unveiling the mechanism for improving the structural, functional and interfacial properties of casein via ultrasound-assisted enzymatic glycosylation and the effect on high internal phase emulsions as curcumin delivery vehicles.

Forward osmosis (FO) membranes have garnered widespread research interest in water treatment, yet their permeability-selectivity trade-off, internal concentration polarization, and membrane fouling remain critical challenges. Herein, a chitooligosaccharide/polydopamine (COS/PDA) co-deposition strategy was proposed to modify polyethersulfone (PES) substrates for constructing high-performance thin-film composite (TFC) FO membranes. COS suppressed excessive PDA aggregation, reduced substrate roughness, and improved substrate hydrophilicity. This substrate modification regulated interfacial polymerization by increasing the adsorption capacity for m-phenylenediamine (MPD) while slowing its diffusion rate, thereby forming thinner, smoother, and more densely crosslinked polyamide (PA) layers. The optimized C4P1-TFC membrane delivered water fluxes of 42.2 and 23.5 L m-2 h-1 in pressure-retarded osmosis (PRO) and FO modes, respectively, representing 43.1% and 40.2% improvements over the pristine membrane. Its specific salt flux decreased to 0.07 and 0.15 g L-1 in the two modes, respectively, suggesting enhanced selectivity. Meanwhile, the C4P1-TFC membrane showed antibacterial rates of 85.7% against Escherichia coli and 86.9% against Staphylococcus aureus, together with improved antifouling performance against bovine serum albumin and lysozyme. This work presents a simple and effective co-deposition approach for simultaneously improving the separation, antibacterial, and antifouling performance of TFC FO membranes, showing promising potential for practical applications.