Wide Temperature Range Research Articles

Evaluating the Influence of Thin Film of Water on the Frequency Dependences of Transmission Line S-Parameters at Positive and Negative Temperatures

Relevance. Provision of reliable and uninterrupted radio communication is critically important under changing climatic conditions of its operation. The combined effect of temperature and humidity can lead to changes in the electrical characteristics of transceiving devices and thereby disrupt the communication channel. In difficult climatic conditions of operation, due to constant temperature changes on the surface of the printed circuit boards, which are part of them, condensation can form, affecting the performance of the entire device. In this regard, the electrical characteristics change, which must be taken into account when designing critical REE. When designing transmission lines on printed circuit boards, it is reasonable to evaluate climatic impacts on it in a wide frequency range, which requires the development of new models and methods that allow taking into account these impacts.Goal of the work: to evaluate the influence of the temperature of a thin film of water on the surface of a microstrip transmission line on its frequency dependences of S-parameters. Finite element methods and laboratory experiment were used.Results. A methodology to account for the effects of ambient temperature and humidity on the electrical characteristics of a microstrip transmission line (MTL) is presented, which allows evaluating the variation of the S-parameters of the line over wide ranges of frequencies, air temperature and humidity, as well as the chemical composition of the environment. The S-parameters of water in a container placed inside a coaxial chamber are measured over the frequency and temperature ranges of 10 MHz to 12 GHz and minus 50 to 100℃, respectively. Using the presented model, the frequency dependences of the electrical conductivity of water at different temperatures are calculated. It is shown that at positive temperature, the electrical conductivity can reach 6.5 Sm/m and at negative temperature it can reach 1.3 Sm/m. Using the developed methodology, the influence of different water electrical conductivity on the S-parameters of MTLs is evaluated. The influence of water and ice layer thickness on the S-parameters of MTLs was shown. It is found that models describing the electrical conductivity of water have an excellent influence on the electrical parameters of the transmission line. Novelty. A method of accounting for the influence of ambient temperature and humidity on the S-parameters of the transmission line is presented, which is characterized by the use of a model of water conductivity based on insertion losses calculated from the measured S-parameters of a coaxial chamber with water in the container when its temperature is changed. Practical significance: a model and a methodology for taking into account the impact of temperature and humidity of the environment on the MTL characteristics are presented, allowing estimating the S-parameters of the line in a wide range of frequencies, air temperature and humidity, as well as the chemical composition of the environment.

Origin of correlated diffuse scattering in the hexagonal manganites

We use a combination of first-principles density-functional calculations and spin-dynamics simulations to explain the unusual diffuse inelastic neutron scattering in the hexagonal multiferroic yttrium manganite, YMnO3. Using symmetry considerations, we construct a model spin Hamiltonian with parameters derived from our density-functional calculations and show that it captures the measured behavior. We then show that the observed directionality in the structured diffuse scattering in momentum space is a hallmark of the triangular geometry, and that its persistence across a wide range of temperatures, both above and below the Néel temperature TN, is a result of the strong magnetic frustration. We predict that this diffuse scattering exists in a yet-to-be-observed modulated continuum of energies, that its associated spin excitations have distinct in-plane and out-of-plane character, and that vestiges of the magnetic frustration persist into the sub−TN state. Finally, we show that visualizing the magnetic order in terms of composite trimer magnetoelectric monopoles and toroidal moments, rather than individual spins, provides insight into the real-space fluctuations, revealing clusters of emerging order in the paramagnetic state, as well as collective short-range excitations in the ordered antiferromagnetic phase. Our understanding of this directional diffuse scattering in such a wide temperature range, both below and above TN, provides new insight into the magnetic phase transitions in classical frustrated systems. Published by the American Physical Society 2024

Transferable and Interpretable Prediction of Site-Specific Dehydrogenation Reaction Rate Constants with NMR Spectra.

Accurate and efficient determination of site-specific reaction rate constants over a wide temperature range remains challenging, both experimentally and theoretically. Taking the dehydrogenation reaction as an example, our study addresses this issue by an innovative combination of machine learning techniques and cost-effective NMR spectra. Through descriptor screening, we identified a minimal set of NMR chemical shifts that can effectively determine reaction rate constants. The constructed model performs exceptionally well on theoretical data sets and demonstrates impressive generalization capabilities, extending from small molecules to larger ones. Furthermore, this model shows outstanding performance when applied to limited experimental data sets, highlighting its robust applicability and transferability. Utilizing the Sure Independence Screening and Sparsifying Operator (SISSO) algorithm, we also present an interpretable rate constant-temperature-NMR (k-T-NMR) relationship with a mathematical formula. This study reveals the great potential of combining machine learning with easily accessible spectroscopic descriptors in the study of reaction kinetics, enabling the rapid determination of reaction rate constants and promoting our understanding of reactivity.

Temperature-Governed Microstructure of Poly(vinyl alcohol) Hydrogels Prepared through Mixed-Solvent-Induced Phase Separation.

The formation of phase-separated structures in hydrogels plays a crucial role in determining their optical and mechanical properties. Traditionally, phase-separated hydrogels are prepared through a two-step process involving initial hydrogel synthesis followed by post-treatment. In this study, we present an approach for temperature-governed phase separation microstructure modulation in hydrogels, harnessing the cononsolvency effect. This method allows the phase-separated structure to develop during hydrogel synthesis, significantly simplifying the preparation process. Importantly, we found that the preparation temperature has a substantial effect on the internal structure of the phase-separated hydrogel. We systematically investigated how the temperature influences the phase structure, optical properties, and mechanical performance of these hydrogels. The resulting hydrogels demonstrate excellent moisturizing and antifreezing capabilities. Additionally, the incorporation of sodium chloride imparts remarkable electrical conductivity to the hydrogels, making them suitable for strain sensing applications across a wide temperature range.

Environment-tolerant, inherently conductive and self-adhesive gelatin-based supramolecular eutectogel for flexible sensor

Although hydrogels have attracted increasing attention in the stretchable devices, the low adhesion properties and poor environmental adaptation still seriously restrict their development and application. Herein, we focused on the interaction between polymer networks with disperse media and their resultant influence on gel performance, and constructed self-adhesive and environment-tolerant gelatin/polyacrylamide supramolecular-polymer double-network (Gelatin/PAM SP-DN) eutectogels using multiple supramolecular interactions between natural macromolecule and well-designed deep eutectic solvent (DES). The dual networks of Gelatin/PAM SP-DN eutectogels produced significant supramolecular forces with DES, including hydrogen bonding and electrostatic interaction, contributing to enhance the energy dissipation capacity. Additionally, the Gelatin-PAM SP-DN eutectogels were more prone to generate strong bonding force to various substrates, showcasing both in-situ and ex-situ adhesion performance, and even being used for wet and underwater adhesion. The eutectogels revealed excellent environmental tolerance to maintain excellent mechanical flexibility, conductivity and adhesion at high and low temperatures, ensuring the constructed sensor to sensitively and reliably perceive strain, pressure and human motions over a wide temperature range. Also, the eutectogel demonstrated great potential as a temperature sensor. This work opens up a new horizon in the design of multifunctional and environment-tolerant natural macromolecule-based gel materials for flexible electronics, human-machine interaction and health diagnosis.

Effects of Temperature, Salinity and CO2 Concentration on Growth and Toxin Production of the Harmful Algal Bloom species Alexandrium pseudogonyaulax (Dinophyceae) from the Danish Limfjord

The marine dinoflagellate Alexandrium pseudogonyaulax is a widely distributed Harmful Algal Bloom (HAB) species that produces the macrocyclic polyketide goniodomin A (GDA). Occurrences in northern European waters are increasing and a spreading of the species along a salinity gradient into the Baltic Sea has been observed. As GDA is suspected to lead to invertebrate mortality, the spreading is of concern for the environment and possibly human health. In order to assess the potential of A. pseudogonyaulax to adapt to the environmental conditions in the Baltic Sea and the risk of future harmful blooms of that species, we quantified the influence of bottom-up factors on the growth and toxin content of three strains of A. pseudogonyaulax from the Danish Limfjord. Specifically, we exposed these strains to salinities ranging from 5 to 50, temperatures in the range of 10 – 30°C and to three different CO2 concentrations of 250, 400 and 1000 µatm. All strains tolerated a broad range of salinities and temperatures, resulting in positive growth rates ranging from 0.06 to 0.33 d-1 between temperatures of 12 and 27°C and between salinities of 10 and 40. The highest cell quotas of GDA were measured at low temperatures. For two strains, GDA amounts were almost unaffected by salinity, while the cell quota of the third strain decreased about 20-fold when salinity increased above 30. Different CO2 concentrations had no effect on growth or GDA production. In summary, these findings show a high ecological tolerance towards a wide range of temperatures and salinities of the Limfjord population of A. pseudogonyaulax, together with distinct intraspecific physiological differences within the population. Our results also suggest that a further spreading into the Baltic Sea might be possible.

Polymer Electrolytes with High Ionic Conductivities at Freezing Temperature for Aqueous Hybrid Batteries.

Rechargeable and flexible aqueous batteries (ABs) have emerged as one of promising energy devices which is primarily due to the safety, environmental friendliness and economic efficiency. However, because of the freezing behavior of aqueous electrolytes, most ABs possess poor performance when the working temperature drops below zero. To solve this problem, a gel polymer electrolyte (GPE) with high ionic conductivity (IC) and frost-resistance is designed for aqueous Zn-Li hybrid batteries by a biomass-based polymers complex consisting of carboxyl modified sodium alginate (SA) and zwitterionic betaine (BA). Introducing iminodiacetic acid to enrich -COOH groups along the SA main chains could improve IC of the prepared GPEs to 41.27 and 20.96 mS cm-1 at 20 and -20 oC, respectively. At -20 oC, the discharge capacity of the resultant cell is two times higher than that of the liquid electrolyte-based cell, and the cell presents a capacity retention of 91.6% after 300 charge/discharge cycles at 1 C. This proposed strategy greatly improve the IC of GPEs at freezing temperature, which is expected to broaden the practical application of GPEs in wide range of temperature.

Quantum turbulence in superfluid helium: Decay and energy spectrum

The paper presents a comprehensive numerical study of the free decay of vortex tangle in superfluid helium. The initial vortex tangle represents one of the stationary configurations of loops in a counterflow with a laminar normal fluid component. The calculations are carried out in the framework of the vortex line method using the full Biot–Savart law over a wide range of temperatures. The aim of the study is to identify the role of various factors introduced into the numerical procedures (removal of small loops and segments during reconnections, the addition of and exclusion of vortex points on loops) and to determine the evolution of energy spectrum during the decay of quantum turbulence. A statistical approach is used to calculate the kinetic energy distribution on length scales. The calculations are carried out using periodic boundary conditions in a cube. The results show that, in agreement with the Feynman–Vinen theory, initially the rates of reduction in vortex line density at different temperatures are the same. However, when the vortex structure becomes rarefied, the influence of the mutual friction force becomes apparent, in agreement with Schwarz's theory. Statistical method for determining the energy spectrum is used. The Kolmogorov spectrum is not observed during decays at any temperature.

Model-based optimization strategies for direct hydrogenation of carbon dioxide to dimethyl ether

This study discusses model-based optimization strategies for CO2 hydrogenation to dimethyl ether (DME) over a CuZnZr (CZZ) and ferrite (FER) mixed catalyst system in a packed-bed reactor configuration. A two-dimensional axisymmetric, nonisothermal packed-bed reactor model was developed using COMSOL Multiphysics 6.2 software. The model solves two-dimensional (radial and axial) heat and mass transport equations in the packed-bed and integrates intraparticle diffusion and heat transfer in a 1D approach. This powerful feature differs from a traditional porous media approach and takes into account any heat and mass transfer limitations that may exist. Analysis shows that the heat transfer limitations are negligible, but strong internal mass transfer limitations were observed at 10 ≤ WHSV ≤ 90 h−1 on the FER catalyst and at 240 °C. The optimum catalyst composition (i.e., mixing ratio) varies depending on the operating regime. The FER catalyst weight in the mixture can be as low as 5 wt.%, but the ideal composition depends on the internal mass transfer limitation and its relationship with the operating regime (i.e., weight hourly space velocity, temperature). A catalyst composition of 80 wt.% CZZ and 20 wt.% FER was suggested; this composition can provide high CO2 conversion and DME production rates at a wide range of temperatures and flow rates.

Greater plasticity in CTmax with increased climate variability among populations of tailed frogs.

Temporally variable climates are expected to drive the evolution of thermal physiological traits that enable performance across a wider range of temperatures (i.e. climate variability hypothesis, CVH). Spatial thermal variability, however, may mediate this relationship by providing ectotherms with the opportunity to behaviourally select preferred temperatures (i.e. the Bogert effect). These antagonistic forces on thermal physiological traits may explain the mixed support for the CVH within species despite strong support among species at larger geographical scales. Here, we test the CVH as it relates to plasticity in physiological upper thermal limits (critical thermal maximum-CTmax) among populations of coastal tailed frogs (Ascaphus truei). We targeted populations that inhabit spatially homogeneous environments, reducing the potentially confounding effects of behavioural thermoregulation. We found that populations experiencing greater temporal thermal variability exhibited greater plasticity in CTmax, supporting the CVH. Interestingly, we identified only one site with spatial temperature variability and tadpoles from this site demonstrated greater plasticity than expected, suggesting the opportunity for behavioural thermoregulation can reduce support for the CVH. Overall, our results demonstrate one role of climate variability in shaping thermal plasticity among populations and provide a baseline understanding of the impact of the CVH in spatially homogeneous thermal landscapes.

Recycling of activated carbons from spent supercapacitors to refabricate improved supercapacitors

The growing market of commercial electric double-layer capacitors (EDLCs) will lead to a vast accumulation of waste as they arrive out of operation. Recycling the spent electrode activated carbon is a closed-loop solution to provide environmental and economic advantages for EDLC use. However, effectively regenerated methods of high-purity activated carbons are still lacked despite their considerable expense. Herein, a simple steam physical activation method is developed to regenerate high-class activated carbons from spent EDLCs. The process is first demonstrated that can effectively eliminate few electrolytes and complex organics as well as regenerate electrode carbon materials. The activation-recycled carbon materials preserve the physicochemical properties of fresh activated carbons and enhance their mesopore ratios, which contributes to improved EDLC performance, obviously surpassing recycled carbon materials by calcination method, including superior specific capacitance of 103.3 F g−1 at 0.5 A g−1, rate performance and cycling stability, equal to fresh activated carbons. Moreover, the assembled activation-recycled carbon material EDLC delivers low self-discharge rate (89 % of initial voltage after 72 h), wide temperature range (−40 to 85 °C), excellent cycling stability (92.2 % capacitance retention after 10,000 cycles) even at elevated voltages (3.0 V) and temperature (65 °C) test. The present work provides an effective and economic method of recycling high-grade activated carbons for sustainable EDLCs.

Achieving wide temperature range of gentle film boiling on textured hydrophobic tool surfaces

Hydrophobic tool surfaces have become a hot topic in recent years due to their significant advantages such as anti-adhesion and friction reduction. However, enhancing hydrophobicity would inadvertently decrease the Leidenfrost point of droplets, which diminishes the heat transfer efficiency and compromises manufacturing quality. This issue presents a considerable challenge and underscores the critical need to understand the boiling dynamics when droplets encounter heated hydrophobic surfaces. Herein, we propose a kind of textured hydrophobic tool surface based on laser processing and hydrophobic coating technology, which could achieve gentle film boiling across a wide temperature range. The raised micropillars protect hydrophobic coating with excellent abrasion resistance and stabilizes the droplets in the gentle film boiling regime under harsh conditions. The primary rationale behind this advancement is the reduction in the critical temperature for film boiling and the elevation of the critical temperature for droplet rebound. We have developed a predictive model for the Leidenfrost point, which has been experimentally validated to determine the wall temperature necessary for achieving the gentle film boiling regime. In addition, we found that the textured hydrophobic surface can still inhibit the bouncing and spreading of droplets at high temperatures. This study not only deepens our understanding of the effects of droplets on heated surfaces but also has the potential to improve manufacturing performance by consistently maintaining the hydrophobic properties of tool surfaces during cutting operations.

Linear viscoelasticity of anisotropic carbon fibers reinforced thermoplastics: From micromechanics to dynamic torsion experiments

The link between experimental characterization and the constitutive behavior of an anisotropic linear viscoelastic unidirectional carbon fiber-reinforced thermoplastic composite is explored using micromechanics modeling. Dynamic torsion tests were conducted at 1 Hz over a wide temperature range, from the glassy to the rubbery states of the polymeric matrix, on both the pure matrix and the composite, for various cutting angles relative to the fibers. A two-step modeling procedure in the frequency domain is presented to predict and validate the effective behavior of the composite. The first step involves FFT-based homogenization, which maps the microstructure and constituent behaviors to effective transversely isotropic viscoelastic properties. The second step consists of finite element simulations using the effective behavior calculated from homogenization as input to replicate the experiments. A comparison between experimental results and model predictions across the entire temperature range is performed. The modeling predictions show good accuracy at low temperatures, where the matrix is in the glassy state. At high temperatures, where the matrix is in the rubbery state, the predicted behavior becomes too soft. As the phase contrast increases and the ratio of matrix bulk modulus to shear modulus rises significantly, the impact of fiber arrangement on the effective properties becomes more pronounced.

Sustainable valorisation of cigarette butts waste through pyrolysis: An insight into the pyrolytic products and subsequent aqueous heavy metals removal by pyrolytic char

In this study, cigarette butts (CB) waste was pyrolyzed over a wide temperature range (400–700 °C) using Pyro/GC–MS and slow pyrolysis experiments. The feedstock and char products were extensively investigated using TGA, elemental analysis, surface area and porosity analysis, SEM-EDS, XRD, and FT-IR, and subsequently tested for their ability to remove Ni (II) and Cu (II) from aqueous solutions. The Pyro/GC–MS analysis revealed the presence of several useful compounds including acids, esters and hydrocarbons. Char yields ranged from 26.6 to 20.1 wt%, and carbon contents varied from 65.3 to 60.8 wt%. The chars produced at medium temperatures (500-600 °C) were highly porous, with a specific surface area of 272.9–270.8 m2/g. The heavy metal adsorption studies revealed that CB 500 °C had the highest adsorption capacity of 13.8 mg/g with 53.4 % nickel removal, while CB 600 °C had the highest adsorption capacity of 23.4 mg/g with 94.7 % copper removal.

High sodium conductive polymer electrolyte-based nanoclusters in supercapacitor

The sodium-ion polymer electrolytes (PEs) spur the development of the high safe solid batteries due to their merits of safety, flexibility, lower interfacial resistance with electrodes, and easy processing. Herein, a rational strategy is developed to construct the PE, which can integrate the excellent sodium ion conductivity with the mechanical performances. This strategy applies the nano-sized metal oxide clusters (MOCs) not only to supply the sodium ions but also to inhibit the polymer crystallization. The released polymer chains, crosslinked via physical crosslinking points (nanoclusters), form a network that provides the electrolyte film with toughness over a wide temperature range. The targeted electrolyte exhibits excellent Na-ion conductivity of 3.8 × 10−4 S cm−1 at room temperature, tensile strength up to 0.74 Mpa and breaking elongation of 23 %. In addition, this PE widens the electrochemical stability window of the aqueous Na-ion supercapacitor up to 2.0 V since the water molecules are effectively confined via the strong interactions among components. Our research on sodium polymer electrolytes combined by nanoclusters and PVA holds significant promise for advancing solid-state sodium saaupercapacitors— a new generation of high-performance, safe, and cost-effective energy storage solutions.

Calculation of collisional line-broadening and shifting of acetylene using Complex Robert–Bonamy–Ma approach

A comprehensive semi-classical study of the collisional line broadening and shift coefficients of C2H2 by several key perturbers (H2, He, N2, C2H2, CO, and CO2) for astronomical applications using the Complex Robert–Bonamy–Ma (CRBM) framework is presented. Following the CRBM computational protocol, the intermolecular interaction potentials are constructed from atom-atom and electrostatic interactions, and then fitted to reproduce experimental room-temperature line-broadening parameters taken from the literature. In total, 657 experimental values are used in the fitting. The empirical potentials are then used to predict line broadening coefficients over a wide temperature range. Reference collisional line widths γ0 and temperature exponents n for the commonly used single-power law are produced, as well as a set of parameters for the double-power law, which better reproduces the temperature dependence of theoretical predictions. The vibrational dependence of the line widths is studied using a new ab initio isotropic polarizability surface of C2H2 and is found to be negligible. The computed line broadening parameters are found to agree well with the experimental data, while the modelling of line shits of HCCH is not satisfactory when compared to the experiment. The new line broadening data of C2H2 with the J (or m) dependence have been used to populate the ExoMol database www.exomol.com as part of the ExoMol pressure-broadening diet and can be used to model opacities of atmosphere of (extrasolar) planets. The CRBM methodology tested here on C2H2 can be used for other similar (closed-shell) systems in ExoMol that are important for exoplanetary atmospheric studies.

Control of Staphylococcus aureus infection by biosurfactant derived from Bacillus rugosus HH2: Strain isolation, structural characterization, and mechanistic insights

Novel antimicrobials are urgently needed to combat methicillin-resistant Staphylococcus aureus (MRSA) infections. This study explores the potential of biosurfactants derived from Bacillus rugosus HH2 as a novel antibacterial agent against MRSA. The biosurfactant, identified as surfactin, demonstrated surface-active properties, reducing surface tension to 37.63 mN/m and lowering contact angles in a concentration-dependent manner. It remained stable across a wide range of pH (4−10), temperatures (30–80 °C), and salinity levels (3–18 %). The biosurfactant inhibited the growth of both methicillin-sensitive S. aureus and MRSA, with minimum inhibitory concentrations ranging from 128 to 256 μg/mL. Additionally, it showed anti-biofilm activity, preventing biofilm formation and dispersing established biofilms. Field-emission scanning electron microscopy revealed that the biosurfactant disrupted bacterial cell membranes, leading to leakage. Furthermore, it reduced the production of virulence factors in S. aureus, including hemolysin and lipase. Transcriptomic analysis indicated downregulation of genes associated with quorum sensing and cell adhesion in MRSA. Molecular docking studies showed strong interactions between surfactin and key MRSA proteins, underscoring its potential to overcome antibiotic resistance. Biocompatibility was confirmed through in vitro cytotoxicity and in vivo phytotoxicity tests. In summary, this study presents surfactin as a promising novel antibacterial agent against MRSA, providing insights into its mechanisms of action.

A novel approach to detailed modeling and simulation of water-gap membrane distillation: Establishing a numerical baseline model

In water-gap membrane distillation (WGMD), natural convection within the water gap significantly impacts performance and thermal efficiency. Previous studies have used empirical or modified empirical correlation models to predict the Nusselt number within the water gap, investigating how natural convection affects WGMD performance and thermal efficiency. However, these models are specific to certain operating conditions, limiting their application in developing a comprehensive numerical model for the WGMD process. To address this limitation, we developed a numerical model by integrating a two-dimensional natural convection model within the water gap. Experimental investigations were conducted across a wide range of feed temperatures and water gap sizes to assess the influence of key operating parameters on performance. To validate the effectiveness of the proposed numerical model, the experimental results were compared with those from the proposed model and with results from numerical models used in previous studies. The proposed numerical model demonstrated a maximum deviation of 8.5% from the measured data, whereas the numerical models used in previous studies exhibited deviations of 22.9%. In addition, the flow characteristics within the water gap were analyzed through isotherms and streamlines, and the improved thermal efficiency of WGMD compared to direct contact membrane distillation (DCMD) was explored.

An Artemisia Sphaerocephala Krash gum/acrylic acid-based novel eco-friendly superabsorbent polymer: Its synthesis and properties promoting seed germination

An affordable, eco-friendly, and salt-tolerant superabsorbent polymer (SAP) has been synthesised from Artemisia sphaerocephala Krasch gum (ASKG), a naturally hydrophilic heteropolysaccharide extracted from the seeds of Artemisia sphaerocephala and acrylic acid (AA) through free-radical polymerisation (ASKG/AA-SAP) using ammonium persulfate (APS) as the initiator and N, N´-methylenebisacrylamide (MBA) as the cross-linker. Morphological and thermal analyses confirmed that ASKG/AA-SAP showed a uniformly interconnected porous structure with a high thermal stability and a gradual decomposition rate. Notably, ASKG/AA-SAP demonstrated exceptional water absorbency, reaching maximum values of 1250g·g-1 in distilled water and 152g·g-1 in a 0.9wt% NaCl solution. Work on relevant parameters related to SAP, viz water absorbency, water retention, and reusability under different influencing factors has been carried out, as also the swelling capacity, salt tolerance, and the ability to withstand a wide range of pH values (4-12) and temperatures (5-55°C). Furthermore, ASKG/AA-SAP has also demonstrated water retention, viz maintaining a rate of 34.19% after 5h in distilled water, which are superior to those of other SAPS tested. Interestingly, the application of ASKG/AA-SAP has resulted in a substantial improvement in seed germination of desert plant, as evidenced by an increase in germination rate and germination energy of Hedysarum scoparium by 58.66% and 35.71%, respectively, compared to the control group. ASKG/AA-SAP, therefore, holds excellent potential for application in agri-forestry production and afforestation works within arid and semi-arid regions.

A polysulfides adsorption strategy through cation-anion interactions for achieving high-safety lithium-sulfur batteries in multiple scenarios

The widespread application of lithium-sulfur batteries (LSBs) is hindered by challenges such as the shuttle effect of polysulfides (LiPSs), slow reaction kinetics, and fire safety concerns. In this study, surface-functionalized boron nitride nanosheets (ChBN) are prepared and employed as functional separator coatings, enabling multiple application scenarios of LSBs. Specifically, a creative strategy of cation-anion interactions is constructed through the strong chemisorption of N+ on the ChBN surface to Sn- in LiPSs. In addition, the boron nitride and N+ showed synergistic effects on adsorption-catalysis, further facilitating the rapid and sufficient deposition of Li2S. The prepared LSBs with ChBN + SP/PP separators exhibit excellent cycle stability (an ultralow capacity degradation of 0.034 % per cycle over 500 cycles at 2C). These LSBs are available over a wide temperature range of −20 to 60 °C, offering a capacity of 1208 mA h/g at 60 °C and 919 mA h/g at −20 °C. Furthermore, the presence of ChBN effectively improves the fire-safety of pouch batteries through the condensed-phase flame retardant mechanism. This simple fabrication process of ChBN is effective and favorable for large-scale manufacturing, which provides a feasible method for the development of high-safety LSBs.