Thermodynamic Interactions Research Articles

Thermodynamical interactions in a rotating magneto-thermoelastic diffusive medium with microconcentrations

Current research is dedicated to study the thermo-mechanical interactions in a rotating magneto-thermoelastic diffusive medium with microconcentrations. The entire thermoelastic medium is rotating with a uniform angular velocity. The formulation is subjected to a mechanical load. Exact solution of the problem is procured by applying normal mode technique. Numerical computations for stresses, displacement components, temperature field, concentration, microconcentration and mass diffusion flux moment are performed for a suitable material and are depicted graphically. Some comparisons are made to show the effects of magnetic field, angular velocity, microconcentration parameter and time on the resulting quantities. Certain special cases of interest have been derived from the current report.

Thermodynamic assessment of the Ca–Sn system

Abstract Thermodynamic modelling of the Ca–Sn binary system was carried out. The thermodynamic parameters related to this system were determined from experimental phase diagram and thermodynamic information available in the literature. In this system the liquid phase was modelled by the association model with the “Ca2Sn” associated complex. This consideration permits to well restore experimental values. A set of thermodynamic interaction parameters, the calculated phase diagram as well as the comparison with experimental data are presented.

Complexation Behaviors of a Tridentate Phenanthroline Carboxamide Ligand with Trivalent f-Block Elements in Different Anion Systems: A Thermodynamic and Crystallographic Perspective.

The counteranion has a strong influence on the complexation behavior of tridentate phenanthroline carboxamide ligands with actinides and lanthanides, but the thermodynamic and underlying interaction mechanism at the molecular level is still not clear. In this work, a tridentate ligand, N-ethyl-N-tolyl-2-amide-1,10-phenanthroline (Et-Tol-PTA), was synthesized, and the effects of different anions (Cl-, NO3-, and ClO4-) on the complexation behavior of Et-Tol-PTA with typical lanthanides were thoroughly studied by using 1H nuclear magnetic resonance (NMR) spectroscopy, ultraviolet-visible (UV-vis) spectrophotometry, and single-crystal X-ray diffraction. The NMR spectroscopic titration of Lu(III) showed that there were three species (1:1, 2:1, and 3:1 ligand-metal complexes) formed in Cl- solution systems while two species (2:1 and 1:1) were formed in NO3- and ClO4- solution systems. When Et-Tol-PTA was titrated with La(III), two species (2:1 and 1:1) were formed in NO3- systems and only one species (1:1) was formed in Cl- and ClO4- systems. In addition, the stability constant was determined via UV-vis spectroscopic titration, which showed that the complexation strength between Et-Tol-PTA and Eu(III) decreased in the following order: ClO4- > NO3- > Cl-. This indicated that Et-Tol-PTA had the strongest complexation ability with Eu(III) in the ClO4- system. The structures of Et-Tol-PTA complexed with EuCl3, Eu(NO3)3, and Eu(ClO4)3 were further elucidated by single-crystal X-ray diffraction and agreed well with the results of UV-vis titration experiments. The results of this work revealed that the mechanisms of complexation of lanthanides with the asymmetric ligand Et-Tol-PTA were strongly affected by different anionic environments in solution and in the solid state. These findings may lead to the improvement of the separation of trivalent actinides and lanthanides in nuclear waste.

Homogeneously Mixing Different Metal-Organic Framework Structures in Single Nanocrystals through Forming Solid Solutions.

Pore engineering plays a significant role in the applications of porous materials, especially in the area of separation and catalysis. Here, we demonstrated a metal–organic framework (MOF) solid solution (MOSS) strategy to homogeneously and controllably mix NU-1000 and NU-901 structures inside single MOF nanocrystals. The key for the homogeneous mixing and forming of MOSS was the bidentate modulator, which was designed to have a slightly longer distance between two carboxylate groups than the original tetratopic ligand. All of the MOSS nanocrystals showed a uniform pore size distribution with a well-tuned ratio of mesopores to micropores. Because of the appropriate pore ratio, MOSS nanocrystals can balance the thermodynamic interactions and kinetic diffusion of the substrates, thus showing exceedingly higher separation abilities and a unique elution sequence. Our work proposes a rational strategy to design mixed-porous MOFs with controlled pore ratios and provides a new direction to design homogeneously mixed MOFs with a high separation ability and unique separation selectivity.

Targeting Natural Polymeric DNAs with Harmane: An Insight into Binding and Thermodynamic Interaction Through Biophysical Approach.

DNA is one of the major molecular targets for a broad range of anticancer drugs. Hence, interaction studies involving cellular DNA and small molecules can be highly beneficial as they often lead to rational and efficient drug design. In this study, the binding interaction of Harmane (a naturally occurring, bioactive indole alkaloid) with two natural polymeric DNAs, that is, Calf thymus (CT) DNA and Herring testis (HT) DNA has been elucidated using biophysical techniques. A ground state, 1:1 complexation, was revealed by steady-state fluorescence spectroscopy. The thermodynamic profile and energetics of the associated reaction were evaluated by temperature-dependent fluorescence spectroscopy. The spontaneity of the binding was confirmed by the negative ΔG° values in both cases. Negative enthalpy change, along with stronger positive entropic contribution, indicated the dominant electrostatic nature of the interaction and finally the entropy-driven exothermic binding process throughout. Salt-dependent studies further demonstrated the significant contribution of electrostatic interactions in ligand binding toward DNA. Infrared data substantiated the structural information of the said interactions, leading to the exploration of the structure-function relationship.

Dynamical and thermodynamical interactions in daily precipitation regimes in the Western Himalayas

AbstractThe mechanisms by which moisture interacts with the Himalayas largely determine the amount of precipitation in Himalayan basins. While many recent studies have focused on mechanisms of independent precipitation events, climatological studies that are essential for a complete understanding of precipitation‐generating mechanisms are limited. This work presents synoptic regimes, which produced precipitation across all seasons in the Western Himalayas (WH) from 2000 to 2018. Using the k‐means clustering algorithm, seven clusters are employed to define relatively mild, moderate and wet regimes, showing distinct seasonality and a synoptic meteorology. We found positive precipitation anomalies at lower elevations in monsoonal regimes (M1, M2 and M3) but at higher elevations in winter (W1 and W2) and transitional regimes (T1 and T2). Moist monsoonal regimes are associated with dynamical interactions between low‐level tropical cyclonic circulations and mid‐level subtropical troughs. Synchronous primary and secondary cyclonic circulations facilitate tropical moisture influx and obstruct the further northward movement of cyclonic circulations, which results in large magnitudes of precipitation at lower elevations in monsoonal regimes. On the other hand, winter regimes exhibit intense western disturbances, which enable orographic ascent of tropical moisture towards higher elevations. Despite weaker dynamical interactions, a stronger thermodynamical instability and a steeper terrain gradient trigger deep convection at higher elevations in transitional regimes. Overall, monsoonal regimes account for 52% of rainy days, whereas winter and transitional regimes account for 20 and 28%, respectively. We present a methodology that identifies hotspots of anomalous precipitation over vulnerable higher elevations by tracking atmospheric variables in Delhi. Our results illustrate the dynamical and thermodynamical interactions responsible for precipitation and highlight the significant contribution from nonmonsoonal regimes to the precipitation across higher elevations in the WH.

On modelling of thermodynamic interaction of particles suspended in two-dimensional medium

Analytical description of temperature distribution in a medium with foreign inclusions is difficult due to the complicated geometry of the problem, so asymptotic and numerical methods are usually used to model thermodynamic processes in heterogeneous media. To be convinced in convergence of these methods the authors consider model problem about two identical round particles in infinite planar medium with temperature gradient which is constant at infinity. Authors refine multipole expansion of the solution obtained earlier by continuing it up to higher powers of small parameter, that is nondimensional radius of thermodynamically interacting particles. Numerical approach to the problem using ANSYS software is described; in particular, appropriate choice of approximate boundary conditions is discussed. Authors ascertain that replacement of infinite medium by finite-sized domain is important source of error in FEM. To find domain boundaries in multiple inclusions’ problem the authors develop “fictituous particle” method; according to it the cloud of particles far from the center of the cloud acts approximately as a single equivalent particle of greater size and so may be replaced by it. Basing on particular quantitative data the dependence of domain size that provides acceptable accuracy on thermal conductivities of medium and of particles is explored. Authors establish series of numerical experiments confirming convergence of multipole expansions method and FEM as well; proximity of their results is illustrated, too.

Electronic Energy and Local Property Errors at QTAIM Critical Points while Climbing Perdew's Ladder of Density-Functional Approximations.

We investigate the relationships between electron-density and electronic-energy errors produced by modern exchange-correlation density-functional approximations belonging to all of the rungs of Perdew's ladder. To this aim, a panel of relevant (semi)local properties evaluated at critical points of the electron-density field (as defined within the framework of Bader's atoms-in-molecules theory) are computed on a large selection of molecular systems involved in thermodynamic, kinetic, and noncovalent interaction chemical databases using density functionals developed in a nonempirical and minimally and highly parametrized fashion. The comparison of their density- and energy-based performance, also discussed in terms of density-driven errors, casts light on the strengths and weaknesses of the most recent and efficient density-functional approximations.

Insight into the interaction mechanisms of N2/H2O/CO2/C mixture at extreme conditions by reactive molecular dynamic simulations

AbstractIn this study, reactive molecular dynamics (RMD) is used to simulate the dynamics of a four‐component mixture containing the detonation products H2O, CO2, N2, and C under high temperatures coupled with high pressures. The thermodynamic properties and interactions of the system were analyzed, and the existence form of carbon clusters was clarified. The results show that the higher the temperature, the faster the potential energy of the system reaches the stable value. There are different types of carbon clusters formed in the system, and most of them include C, N, and O. Carbon clusters with only C atoms are very few. This is due to the high activity of the N and O radicals at high temperature, which form new bonds with the C atoms easily. Besides, the ring‐shaped carbon clusters appear with the increase in pressure. It may be inferred that large carbon clusters are easy to form in the temperature range 2000–3000 K and pressure range 25–35 GPa. Our research provides a new insights into the interaction and thermodynamic properties of four‐component detonation products under extreme conditions and is helpful for designing new explosives and establishing their equations of state.

Ternary diffusion and thermodynamic interaction in the <i>β</i> solid solutions of Ti-Al-Zr alloys at 1473 K

Ternary diffusion and thermodynamic interaction in the <i>β</i> solid solutions of Ti-Al-Zr alloys at 1473 K

Thermodynamic constraints on the assembly and diversity of microbial ecosystems are different near to and far from equilibrium.

Non-equilibrium thermodynamics has long been an area of substantial interest to ecologists because most fundamental biological processes, such as protein synthesis and respiration, are inherently energy-consuming. However, most of this interest has focused on developing coarse ecosystem-level maximisation principles, providing little insight into underlying mechanisms that lead to such emergent constraints. Microbial communities are a natural system to decipher this mechanistic basis because their interactions in the form of substrate consumption, metabolite production, and cross-feeding can be described explicitly in thermodynamic terms. Previous work has considered how thermodynamic constraints impact competition between pairs of species, but restrained from analysing how this manifests in complex dynamical systems. To address this gap, we develop a thermodynamic microbial community model with fully reversible reaction kinetics, which allows direct consideration of free-energy dissipation. This also allows species to interact via products rather than just substrates, increasing the dynamical complexity, and allowing a more nuanced classification of interaction types to emerge. Using this model, we find that community diversity increases with substrate lability, because greater free-energy availability allows for faster generation of niches. Thus, more niches are generated in the time frame of community establishment, leading to higher final species diversity. We also find that allowing species to make use of near-to-equilibrium reactions increases diversity in a low free-energy regime. In such a regime, two new thermodynamic interaction types that we identify here reach comparable strengths to the conventional (competition and facilitation) types, emphasising the key role that thermodynamics plays in community dynamics. Our results suggest that accounting for realistic thermodynamic constraints is vital for understanding the dynamics of real-world microbial communities.

Abstract P252: IMM-1-104: a novel, oral, selective dual-MEK inhibitor that displays broad antitumor activity and high tolerability across RAS and RAF mutant tumors in vivo

Abstract Background: Inappropriate activation of the MAPK pathway, often stemming from mutations in RAS or RAF, represents one of the most common oncogenic events in human cancer. Therefore, MEK1 and MEK2 (MEK), which lie downstream of RAS and RAF but upstream of ERK, have represented an attractive drug target for over two decades. Unfortunately, first generation MEK inhibitors have been limited by pathway reactivation events and serious on-target drug toxicities that restrain clinical utility, especially in patients with RAS mutant tumors. We sought to develop a new approach to MEK inhibition that would be more effective in RAS mutant tumors and with improved tolerability. IMM-1-104 is a novel dual-MEK inhibitor that is designed to disrupt phosphorylation of MEK and subsequently prevent activation of ERK1 and ERK2 (ERK). IMM-1-104’s dual-MEK mechanism resists RAF activation of MEK, and its short drug half-life allows for chronic dosing while maintaining a near-zero drug trough for improved tolerability. Materials & Methods: IMM-1-104 was profiled across a series of preclinical experiments to assess its physicochemical and drug-like properties. Cell-free and cell-based in vitro as well as in vivo characteristics were evaluated, including four independent in vivo pharmacology rodent studies in lung, colon and skin tumor models. Results: IMM-1-104 is a highly selective, orally bioavailable, non-ATP competitive, allosteric dual-MEK inhibitor. At drug exposures up to 1 micromolar (uM) in cell-free and in situ kinome screens, thermodynamic interactions and altered activity levels were observed for MEK1 and MEK2. At higher drug exposures up to 10 uM, IMM-1-104 also thermodynamically interacted with RAF1 (CRAF) and prompted reduction of KSR1 and KSR2 activation markers. IMM-1-104 displayed dual-MEK activity (i.e., RAS mutant tumor cell reductions in both ERK and MEK phosphorylation) across multiple human tumor cell-based models including A549 (KRAS-G12S) lung, A375 (BRAF-V600E) and SK-MEL-2 (NRAS-Q61R) melanoma. Pharmacokinetic studies in rodent models revealed a drug plasma half-life for IMM-1-104 of approximately 1.3 hours. In vivo tumor pharmacology studies in A549 and A375 achieved tumor stasis (i.e., 85% to 95% Tumor Growth Inhibition) with regressions observed in Colon-26 and SK-MEL-2. Conclusions: The dual-MEK mechanism and short half-life of IMM-1-104 has proven to be broadly active and well-tolerated in multiple RAS and RAF mutant preclinical tumor models in rodents. IMM-1-104 drives deep, cyclic inhibition of the MAPK pathway (improving tolerability) while resisting pathway bypass mechanisms (improving activity). Our collective data suggest that RAS and RAF mutant tumor cells are not able to tolerate periods of deep but cyclic MAPK pathway inhibition. Overall, these results are consistent with on and off signaling events that can significantly impact cell fate decisions (i.e. signaling dynamics). Citation Format: Peter J. King, Kevin D. Fowler, Sarah E. Kolitz, Scott Barrett, Benjamin J. Zeskind, Brett M. Hall. IMM-1-104: a novel, oral, selective dual-MEK inhibitor that displays broad antitumor activity and high tolerability across RAS and RAF mutant tumors in vivo [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P252.

THE THERMODYNAMICS OF INTERACTIONS AND RELAXATION PROPERTIES OF THE POSS-CONTAINING NANOCOMPOSITES BASED ON POLYURETHANE-POLY(HYDROXYPROPYL METHACRYLATE) MATRIX, WHICH IS FORMED BY THE PRINCIPLE OF IPNS

A series of the nanocomposites based on a multicomponent polymer matrix consisting of polyurethane and poly(hydroxypropyl methacrylate) and 1,2-propanediolysobutyl polyhedral oligomeric silsesquioxane (1,2-propanediolysobutyl-POSS), used as a functionalized nanofiller, was synthesized. The polymer matrix was formed on the principle of interpenetrating polymer networks (IPNs). The influence of 1,2-propanediolysobutyl-POSS amount on the thermodynamics of polymer components of the matrix interactions and on the dynamic mechanical properties of the created nanocomposites was studied. With purpose of the thermodynamic parameters interactions calculations the isothermal sorption of methylene chloride vapour by samples was investigated. The methylene chloride vapour sorption by the samples was studied using a vacuum installation and a McBain balance. By calculations of the thermodynamic parameters of PU and PHPMA interactions was shown that the free energy of PU and PHPMA mixing was positive. The introduction of 1-3 wt % of POSS lead to further phase separation in semi-IPNs. This is due to concentration of POSS particles in the PU’s nanodomains. The increasing of POSS content up to 5-10 wt % lead to compatibi-lization in semi-IPNs. These is due to concentration of POSS nanoparticles not only in the PU’s nanodomains but also in the interphase region of semi-IPN. The dynamic mechanical properties of the created nanocomposites were investigated and the degree of polymer components segregation was calculated. It was shown that there are two peaks of tan δ (PU and PHPMA) in the nanocom-posites. The introduction of 1-3 wt % of POSS lead to increasing of tan δ peak of PHPMA and to deepening of the bridge between two peaks (PU and PHPMA). At the same time the degree of polymer components of the matrix segregation became higher. This means the further phase separation in semi-IPNs. Increasing of 1,2-propanediolysobutyl-POSS amount up to 5-10% leads to the concentration of the nanofiller not only in the nanodomains of PU, but also in the interfacial layers. This leads to a change in the free energy of polymer components mixing, which becomes negative. At the same time the degree of polymer components of the matrix segregation became significantly reduced. These means that the process of compatibilization took part in the semi-IPNs.

In silico analyses of major active constituents of fingerroot (Boesenbergia rotunda) unveils inhibitory activities against SARS-CoV-2 main protease enzyme

Boesenbergia rotunda (L.) Mansf., commonly known as fingerroot is a perennial herb in the Zingiberaceae family with anticancer, anti-leptospiral, anti-inflammatory, antioxidant, antiulcer, and anti-herpes viral activities. While the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inhibitory activity of B. rotunda extract has been recently found, the active compounds contributing to this activity are yet unknown. The main protease (Mpro) enzyme is one of the most well established therapeutic targets among coronaviruses which plays a vital role in the maturation and cleavage of polyproteins during viral replication. The current work aims to identify active phytochemical substances from B. rotunda extract that can inhibit the replication of SARS-CoV-2 by using a combined molecular docking and dynamic simulation approaches. The virtual screening experiment revealed that fifteen molecules out of twenty-three major active compounds in the plant extract have acceptable drug-like characteristics. Alpinetin, Pinocembrin, and Pinostrobin have binding energies of −7.51 kcal/mol, −7.21 kcal/mol, and −7.18 kcal/mol, respectively, and can suppress Mpro activity. The stability of the simulated complexes of the lead compounds with the drug-receptor is demonstrated by 100-ns MD simulations. The binding free energies study utilizing molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) and molecular mechanics generalized Born surface area (MM-GBSA) show that the compounds and Mpro enzyme have favourable thermodynamic interactions, which are majorly driven by van der Waals forces. Thus, the selected bioactive phytochemicals from B. rotunda might be used as anti-SARS-CoV-2 candidates that target the Mpro enzyme.

Design, Synthesis, Antibacterial Activity and in Silico Studies of Novel Quinolone Fused with Triazine, Thiadiazole and Oxadiazole Heterocycles

We have strategically designed and synthesized some novel quinolone fused with hybrid heterocycles 7-chloro-1-ethyl-6-fluoro-4-oxo-N'-(arylcarbonothioyl)-1,4-dihydroquinoline-3-carbohydrazides (3a–m), 7-chloro-1-ethyl-6-fluoro-3-(5-mercapto-4-aryl-4H-1,2,4-triazol-3-yl)quinolin-4-ones (4a–m), 7-chloro-1-ethyl-6-fluoro-3-(5-(arylamino)-1,3,4-thiadiazol-2-yl)quinolin-4(1H)-ones (5a–m) and 7-chloro-1-ethyl-6-fluoro-3-(5-(arylamino)-1,3,4-oxadiazol-2-yl)quinolin-4(1H)-ones (6a–m) and screened them against bacterial strains. Results of antibacterial efficacy revealed that compounds with electron-withdrawing groups like 3b, 3c, 3d, 4c, 4d, 4e, 5b, 5c and 5d showed better activity against different bacterial strains among the synthesized compounds 3a–m, 4a–m, and 5a–m while compounds having electron-donating groups like 6h, 6i, 6j and 6k displayed better activity in synthesized compounds 6a–m. Furthermore, molecular docking against microbial DNA gyrase could throw light into the plausible mechanism of action and thermodynamic interactions governing the binding of these molecules. The article provides various synthetic approaches for strategically designed different hybrid heterocycles which were further evaluated for their biological activities against bacterial strains, to offer the findings for future research and to give a path-breaking lead in designing potent compounds managing the bacterial resistance strains.

Effects of Molecular Crowders on Single-Molecule Nucleic Acid Folding: Temperature-Dependent Studies Reveal True Crowding vs Enthalpic Interactions.

Biomolecular folding in cells can be strongly influenced by spatial overlap/excluded volume interactions (i.e., "crowding") with intracellular solutes. As a result, traditional in vitro experiments with dilute buffers may not accurately recapitulate biomolecule folding behavior in vivo. In order to account for such ubiquitous excluded volume effects, biologically inert polyethylene glycol (PEG) and polysaccharides (dextran and Ficoll) are often used as in vitro crowding agents to mimic in vivo crowding conditions, with a common observation that high concentrations of these polymers stabilize the more compact biomolecule conformation. However, such an analysis can be distorted by differences in polymer interactions with the folded vs unfolded conformers, requiring temperature-dependent analysis of the thermodynamics to reliably assess competing enthalpic vs entropic contributions and thus the explicit role of excluded volume. In this work, temperature-controlled single-molecule fluorescence resonance energy transfer (smFRET) is used to characterize the thermodynamic interaction between nucleic acids and common polymer crowders PEG, dextran, and Ficoll. The results reveal that PEG promotes secondary and tertiary nucleic acid folding by simultaneously increasing the folding rate while decreasing the unfolding rate, with temperature-dependent studies confirming that the source of PEG stabilization is predominantly entropic and consistent with a true excluded volume crowding mechanism. By way of contrast, neither dextran nor Ficoll induces any significant concentration-dependent change in nucleic acid folding stability at room temperature, but instead, stabilization effects gradually appear with a temperature increase. Such a thermal response indicates that both folding enthalpies and entropies are impacted by dextran and Ficoll. A detailed thermodynamic analysis of the kinetics suggests that, instead of true entropic molecular crowding, dextran and Ficoll associate preferentially with the unfolded vs folded nucleic acid conformer as a result of larger solvent accessible surface area, thereby skewing the free energy landscapes through both significant entropic/enthalpic contributions that compete and fortuitously cancel near room temperature.

Efficient Treatment of Fish Intestinal Parasites Applying a Membrane-Penetrating Oral Drug Delivery Nanoparticle.

Nanodelivery of drugs aims to ensure drug stability in the face of adverse biochemical conditions in the course of administration, concomitant with appropriate pharmacological action provided by delivery at the targeted site. In this study, the application potential of a nanoparticle produced with biopolymers chitosan-N-arginine and alginate as an oral drug delivery material is evaluated. Both macromolecules being weak polyelectrolytes, the nanoparticle presents strong thermodynamic interactions with a biological model membrane consisting of a charged lipid liposome bilayer, leading to membrane disruption and membrane penetration of the nanoparticles in ideal conditions of pH corresponding to the oral route. The powder form of the nanoparticle was obtained by lyophilization and with a high percentage of entrapment of the anthelmintic drug praziquantel. In vivo studies were conducted with oral administration to Corydoras schwartzi fish with high intensity of intestinal parasites infection. The in vivo experiments confirmed the mucoadhesive and revealed membrane-penetrating properties of the nanoparticle by translocating the parasite cyst, which provided target drug release and reduction of over 97% of the fish intestinal parasites. Thus, it was evidenced that the nanoparticle was effective in transporting and releasing the drug to the target, providing an efficient treatment.

Exploring Sources of Surface Bias in HRRR Using New York State Mesonet

AbstractIn recent years, there has been increasing demand for applications of short‐term forecasting of renewable energy potential and assessments of the likelihood of extreme weather events using the High‐Resolution Rapid Refresh (HRRR) model. Examining the biases in the newest version of HRRR is necessary to promote further model development. Using data from one of the most comprehensive and dense monitoring networks, New York State Mesonet (NYSM), we evaluate the HRRR version 3 meteorological fields for an entire year. In this work, the land‐atmosphere‐cloud coupling system is evaluated as an integrated whole. We investigate the physical processes influencing the soil hydrological balance and the thermodynamic interactions, from surface fluxes up to the level of boundary layer convection from both temporal (seasonal and diurnal) and spatial perspectives. Results show that the model 2 m temperature and humidity biases are seasonally dependent, with warm and dry bias present during the warm season, and an extreme nocturnal cold bias in winter. The summer warm bias includes both a land‐surface‐induced bias and a cloud‐induced bias. Inaccurate representation of energy partition and soil hydrological process across different land use types as well as a hydrological bias in describing spring snowmelt are identified as the main source of the land‐surface‐induced bias. A feedback loop linking cloud presence, flux changes, and temperature contributes to the cloud‐induced bias. The positive solar radiation bias increases from clear sky to overcast sky conditions. The most significant bias occurs during overcast and thick cloud conditions associated with frontal passage and thunderstorms.

Ionic Transport and Thermodynamic Interaction in Precision Polymer Blend Electrolytes for Lithium Batteries

AbstractSingle‐ion conducting polymer electrolytes are of interest for use with advanced battery electrodes such as lithium metal, but achieving sufficiently high conductivity has been challenging. In this work, a model system containing charged sites that are precisely spaced along the polymer backbone is explored. Precision sulfonated poly(4‐phenylcyclopentene) lithium salt (p5PhS‐Li) with a high degree of sulfonation (> 90%) is synthesized and blended with poly(ethylene oxide) (PEO) to investigate the thermodynamic and transport properties. Melting point depression is measured via differential scanning calorimetry, ionic conductivity,κ, is determined using electrochemical impedance spectroscopy, and the fraction of current carried by Li+is estimated based on steady‐state current measurements. In conjunction with a density measurement, melting point depression is used to find an effective Flory–Huggins interaction parameter,χeff= − 0.21, suggesting miscibility of the blend.κspans a large range from 2 × 10−11to 2 × 10−7S cm−1over the composition and temperature range investigated. The fraction of charge carried by lithium ions also spans a significant range from 0.12 in majority PEO blend to 0.98 in majorityp5PhS‐Li blend. This study addresses several limitations of sulfonated polystyrene and opens up the possibility of precisely controlling the spacing of other anion types.

Comparing Internal and Interparticle Space Effects of Metal-Organic Frameworks on Polysulfide Migration in Lithium-Sulfur Batteries.

One of the critical issues hindering the commercialization of lithium–sulfur (Li–S) batteries is the dissolution and migration of soluble polysulfides in electrolyte, which is called the ‘shuttle effect’. To address this issue, previous studies have focused on separators featuring specific chemical affinities or physical confinement by porous coating materials. However, there have been no studies on the complex effects of the simultaneous presence of the internal and interparticle spaces of porous materials in Li–S batteries. In this report, the stable Zr-based metal–organic frameworks (MOFs), UiO-66, have been used as a separator coating material to provide interparticle space via size-controlled MOF particles and thermodynamic internal space via amine functionality. The abundant interparticle space promoted mass transport, resulting in enhanced cycling performance. However, when amine functionalized UiO-66 was employed as the separator coating material, the initial specific capacity and capacity retention of Li–S batteries were superior to those materials based on the interparticle effect. Therefore, it is concluded that the thermodynamic interaction inside internal space is more important for preventing polysulfide migration than spatial condensation of the interparticle space.