Low Energy Levels Research Articles

Mechano-driven logic-in-memory with neuromorphic triboelectric charge-trapping transistor

In the post-Moore's Law era, there is a growing trend towards the development of advanced electronic devices that combine sensory perception, data storage, and computation for various applications. Two-dimensional semiconductor transistors, which utilize charge storage mechanisms, present a promising avenue for future information devices. Here, we introduce a neuromorphic triboelectric charge-trapping MoTe2 transistor with stacked high-k dielectric structure, aiming to facilitate mechano-driven logic-in-memory for neuromorphic computation. By gating through triboelectric potential, the device demonstrates superior electrical performance, including an impressive switching ratio (>105), minimal off-state current (∼0.6 pA), and robust cyclic stability. By modulating the trapped charges in the stack gate structure via tribopotential modulation, the conductivity state of the MoTe2 channel can be readily controlled, realizing an exceptional mechano-driven nonvolatile memory with a retention time of up to 104 seconds, consistent switching behavior over 100 cycles, and multi-level data storage capabilities at 8 levels. Furthermore, a mechano-driven programmable inverter can be achieved by connecting a load resistor in series. The triboelectric charge-trapping transistor also possesses the capacity to emulate typical synaptic characteristics at low energy levels (∼147 fJ). Leveraging the finely tunable conductivity through tribopotential, we demonstrate a mechano-assisted artificial neural network capable of recognizing handwritten digits with an accuracy rate of approximately 88.59%. These findings underscore the significant potential of the triboelectric charge-trapping transistor in mechanical-assisted real-time interaction, energy-efficient data storage, and neuromorphic computing.

Substituent effect on the electronic and optical properties of newly designed pyrrole derivatives using density functional theory

Abstract This work explores six newly designed compounds obtained by several substitutions in 2,5-di(2-thienyl) pyrrole molecule. For this series of compounds, the electronic and optical properties were investigated using density functional theory and time-dependent density functional theory (TD-DFT). The new compounds were characterized by calculating the chemical parameters that correlated with their optical and electrical properties. The lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) energies are calculated using the B3LYP functional with the 6-311G (d, p) basis set. The most low-lying energy level of the LUMO was found for Perr-NO2, indicating its effective electron injection capabilities and oxidation resistance. The HOMO and LUMO distributions of Perr-Cl and Perr-NO2 displayed a remarkable complementarity throughout each component of the two compounds, indicating an effective intermolecular charge transfer. The molecular electrostatic potential analysis demonstrated that the proposed compounds have a broad distribution of electrophilic and nucleophilic sites, which predict a high degree of chemical reactivity. The electron density analysis at the bonding and anti-bonding sites of the title compounds was performed using the electron localization function and local orbital locator techniques. Non-covalent interaction analysis using the reduced density gradient approach classified all types of interaction: repulsive, weak, and attractive interactions within compound fragments. All compounds exhibited a robust repulsive interaction, as proved by the red spikes at 0.038 a.u. The ultraviolet/visible (UV/vis) spectrum was obtained by TD-DFT using CAM-B3LYP models in conjunction with 6-311G (d, p) basis set and methanol as a solvent, the absorption bands were found within the UV range, and the maximum wavelength showed red-shifted increases. These compounds could serve as a base material for developing selective gas sensors with considerable UV/vis absorption (180–400 nm). According to the research results, the designed compounds are good candidates for use as precursors in polymer designs for optoelectronic and sensor applications due to their high electrical conductivity and photochemical properties.

Mosaic vaccine design targeting mutational spike protein of SARS- CoV-2: An immunoinformatics approach

Introduction: Presently, the development of effective vaccines against SARS-CoV-2 is absolutely necessary, especially regarding the emergence of new variants that cause increasing morbidity and fatalities. Methods: In the present study we designed a mosaic vaccine targeting the mutational spike protein of COVID-19 using a bioinformatics approach. Various immunoinformatics tools were utilized to provide the highest potential for a mosaic vaccine that could activate immune responses against COVID-19. Results: The evaluation of the constructed vaccine revealed that it is antigenic and immunogenic as well as nonallergenic. The physicochemical properties also show promising characteristics, including being highly stable and hydrophilic. As expected, the vaccine shows strong interactions with several important receptors including angiotensin-converting enzyme 2 (ACE2), Toll-like receptor 3 (TLR3) and TLR8 by the lowest energy level, docking score and binding free energy. The vaccine binds to receptors via certain amino acids using various types of binding including salt bridges, hydrogen bonds, and other means. As shown in computationally derived models, the interactions promote activation of the immune response by eliciting the release of various cytokines, antibodies, memory B and T cells, as well as increasing of natural killer cell and dendrite cell counts. Conclusion: Therefore, the novel designed mosaic vaccine could be considered as a potential vaccine candidate for immediate production to stem the continuing and tragic effects of the COVID-19 pandemic. However, several advanced experimental studies should be conducted to ensure and verify the effectivity and safety against SARS‑CoV‑2 in vivo.

Slow sustained releasing LiNO3 from graphite electrode reservoir to regulate solvation structure and stabilize interface

The high de-solvation energy derived from the solvent-rich Li+ solvation sheath and the resultant porous organic-rich electrode/electrolyte interface has hindered the commercialization of low-concentration electrolytes (LCEs). Here, unlike the common method so far reported, we invent an approach of sustained releasing LiNO3 from the graphite (Gr) anode reservoir to optimize the solvation structure and form a stable interface in LCEs. The solubility limit can be overcome by introducing LiNO3 directly in the Gr slurry. Moreover, the stronger binding energy between NO3– and Li+ drives NO3– enter the Li+ solvation sheath, weakening the shielding effect of solvent on Li+, and surprisingly increasing the coordination of PF6- to Li+. Thermodynamically, the corresponding lowest unoccupied molecular orbital energy levels of anions decrease, reducing the de-solvation energy of Li+ and forming a Li3N&LiF-rich solid electrolyte interface (SEI). This inorganic-rich SEI demonstrates advantages of inhibiting the decomposition of solvent and facilitating the transmission of Li+. As a result, the cell with Gr anode containing 1 wt% LiNO3 exhibits superior cycle performance in LCE, almost no degradation within 200 cycles, even higher than that in conventional concentration electrolyte. More importantly, the continuous consumption of NO3– in turn promotes its sustained redissolution from the anode, constituting a virtuous circle of regulating solvation structure, stabilizing interface and improving battery performance. This work blazes a new trail to revive lithium salt additives with low solubility, and expands the design strategy and application prospect of LCEs by building the bridges between regulating the solvation structure and constructing favorable electrode/electrolyte interface.

Structural Properties and Photocatalytic Activity of TiO2/Au Nanocomposites Synthesized with Glucose

AbstractA one‐pot synthesis of plasmonic gold‐modified TiO2 nanocomposites is reported by using glucose reduction of HAuCl4 in presence of titanium tetraisopropoxide. The resulting nanocomposites are characterized by thermal‐gravimetric analyses, X‐ray diffraction combined with X‐ray fluorescence and photoelectron spectroscopies. A binary system of β‐TiO2 and anatase phases is obtained for low Au content while only anatase form is favored when the initial Au rate rises. This investigation also suggests the inclusion of gold in the TiO2 structure. Although the optical bandgap of the different nanocomposites remains around 3 eV, the increase of Au content induces a shift of both valence and conduction edge bands to lower energy levels. The photocatalytic activity of TiO2/Au nanocomposites is assessed through the decolorization of different cationic and anionic dyes as model compounds. Regarding rhodamine and methylene blue dyes, the sample TiO2 modified with 3.5 wt% of Au presents the best performance. The relation between the structure of the nanocomposites and their capacity to degrade pollutants is discussed.

Effect of nitro-substituted ending group on the photovoltaic and photocatalytic performance of non-fullerene acceptors

The Y-series non-fullerene acceptors (NFAs) significantly enhance organic photovoltaic device efficiency, approaching 20%. Recent studies demonstrate their commendable photocatalytic performance in bulk heterojunction photocatalysis. Chemical modification of end groups emerges as a pivotal way to modulate molecular electrical and optical characteristics, thereby improving the organic solar cells (OSCs) performance. Among Y-series NFAs, 2-(2,3-dihydro-3-oxo-1H-inden-1-ylidene)propanedinitrile (INCN) and its derivatives stand out as the most successful end groups. However, a restricted range of modifying groups, such as the fluorine atom (–F) and the hydroxyl group (–OH), are currently employed to explore both the photovoltaic and photocatalytic properties of Y-series NFAs, research on other substituents for INCN remains largely unexplored to date. In this study, nitro-substituted end groups were incorporated into the Y6 skeleton, resulting in a new NFA, named Y6-NO. Simultaneously, INCN is incorporated into the Y6 skeleton to create Y6-IN as a reference molecule for simultaneously investigating the photovoltaic and photocatalytic properties of the two NFAs. In organic photovoltaics, Y6-NO, featuring nitro groups, exhibits a red-shifted absorption, lower molecular energy levels, and enhanced electron transport, leading to a superior power conversion efficiency (PCE) of 17.03 % for OSCs, as opposed to 10.45 % for Y6-IN. Conversely, in the photocatalytic hydrogen evolution reaction (HER) for water splitting, the nitro groups in Y6-NO lowers the energy level of the lowest unoccupied molecular orbital (LUMO), resulting in a reduced overpotential when combined with the co-catalyst Pt. Consequently, the HER rate of PM6:Y6-NO nanoparticles (72.2 mmol h−1 g−1) is lower than that of PM6:Y6-IN nanoparticles (108.5 mmol h−1 g−1). This study highlights that through judicious end-group chemical modification, the photovoltaic and photocatalytic properties of the acceptors can be effectively modulated.

Thienyl naphthodipyrrolopyrrole (TNDP)-based polymers semiconductor for n-type OFETs

Naphthodipyrrolopyrrole (NDP)-based materials as the n-type semiconductor materials are investigated, which present a good electron transport mobility. However, all the reported NDP were phenyl-substituted ones (PhNDP). Compared to the phenyl substituted chromophore, the thiophene substituted ones were often more promising due to its small size, S⋯S interaction, as well as the electron-rich behavior for the thiophene. Thus, in this work the new chromophore thiophene-substituted NDP (TNDP) was designed and synthesized for the first time via Knoevenagel reaction. In addition, two donor-acceptor typed copolymers PNDP-2T and PNDP-IDT containing TNDP were prepared. The result showed that the two polymers present not only a good aggregation and strong intramolecular charge transfer (ICT) effect, but also a low lowest unoccupied molecular orbital (LUMO) ∼ -4.17 eV. This is advantageous for the charge transport within the single molecules as well as across the neighboring polymer chains. In addition, the low LUMO energy level is beneficial for the electron injection from electrode into the semiconductor layer. As a consequence, both polymers presented n-type behavior. The electron transport mobility of PNDP-IDT was up to 0.99 cm2 V−1 s−1, which is among the highest electron mobility reported for conjugated polymers. In addition, this value is higher than the PNDP-based polymers with similar chemical structure. This work clearly shows that TNDP is an appealing electron-deficient building block for novel π-conjugated polymers with application potential in the n-channel semiconductors.

Tuned the refractive index and absorption edge for Fuchsin basic dye-doped (PVA-PVP-PEG) films: Linear and nonlinear optical characterization for blocking intense laser power

The current investigation focused on creating dye-doped polymer blend films using a solution cast method with a composition of 60%PVA-30%PVP-10%PEG. These films displayed altered refractive index and absorption edge properties. Various characterization techniques, including XRD, FTIR, UV–vis spectroscopy, and optical limiting effects, were utilized to analyze the structural and optical features of the dyed films. The doped samples showed noticeable changes in the structural properties of the polymer matrix blend, as evident from their XRD and FTIR patterns. Incorporating FB dye into the blend resulted in absorption spectra appearing in multiple bands between 295 and 560 nm. For 532.8 nm He-Ne lasers, the FB/(PVA-PVP-PEG) blend was found to be ideal due to its transmittance CUT-OFF within the 200–600 nm wavelength range. The addition of FB dye had a significant impact on the optical characteristics of the polymer blend, leading to a shift in the absorption edge towards lower photon energy levels. The presence of FB dye was also observed to influence the refractive index (n) of the host polymer, indicating its potential for adjusting optical properties. Detailed investigations into the bandgap revealed a reduction in the bandgap of the host polymer due to the presence of the dye. Electronic transitions were further examined through the εi(ω) parameter during the bandgap analysis, confirming the role of the dye in altering the optical bandgap. Overall, the synthesized FB/(PVA-PVP-PEG) polymeric films hold promise for various optoelectronic applications, including lasers, optical filters, communication devices, LEDs, and optical switches.

Sea Surface Height Wavenumber Spectrum from Airborne Interferometric Radar Altimeter

The proposed “Guanlan” ocean science satellite, led by China’s Laoshan Laboratory, includes an interferometric radar altimeter (IRA) as a key payload. As an integral part of its development, an airborne IRA experiment was conducted on 6 November 2021, with a flight path of approximately 90 km in the South China Sea. This study investigates the IRA’s ability to observe ocean sea surface height (SSH) across scales ranging from meters to mesoscale. The sea surface height anomaly (SSHA) of the IRA is aligned with the SSHA of the AVISO at scales greater than 30 km, but also demonstrates the ability to capture small-scale SSHA changes in two dimensions. We analyzed wavenumber spectra of SSHA obtained from the airborne IRA, ICESat-2, and SARAL/AltiKa satellite for this region. The results show a good agreement in power spectral density (PSD) levels between ICESat-2, SARAL/AltiKa and IRA at scales larger than 30 km. Within the submesoscale range of 1–10 km, the IRA SSHA spectrum exhibits a distinctly negative slope and the lowest energy level. The minimum PSD level of the IRA fell in the range of 10−4–10−3 m2/cycle/km, at scales around 1 km, which is more than an order of magnitude lower than that of ICESat-2, forming a spectral gap that is in agreement with the theoretical expectation. Furthermore, IRA-derived wave direction and significant wave height matched well with the MFWAM wave data. The results of this study underscore the considerable potential of airborne IRA in capturing SSHA across a range of scales, from oceanic waves to submesoscale.

In Situ Polymerized Quasi-Solid Electrolytes Compounded with Ionic Liquid Empowering Long-Life Cycling of 4.45 V Lithium-Metal Battery.

High-voltage resistant quasi-solid-state polymer electrolytes (QSPEs) are promising for enhancing the energy density of lithium-metal batteries in practice. However, side reactions occurring at the interfaces between the anodes or cathodes and QSPEs considerably reduce the lifespan of high-voltage LMBs. In this study, a copolymer of vinyl ethylene carbonate (VEC) and poly(ethylene glycol) diacrylate (PEGDA) was used as the framework, with a cellulose membrane (CE) as the supporting layer. Based on density functional theory calculations, 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI), an ionic liquid, was screened because of its lowest unoccupied molecular orbital energy level as a modifying agent for the in situ P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs synthesis. Pyr14+, with a lithiophobic alkyl chain, forms a dense positive ion shielding layer on the protruding tips of deposited lithium, facilitating uniform and smooth lithium deposition. Pyr14TFSI assists in constructing a stable solid electrolyte interphase (SEI) layer on the Li surface enriched with LiF, Li3N, and RCOOLi. The modulation of lithium deposition behavior on the anode by Pyr14TFSI ensures stable Li plating/stripping for >1500 h. A Li-Cu cell exhibits stable cycling for >200 cycles at a current density of 0.05 mA cm-2, with an average Coulombic efficiency of 92.7%. In situ polymerization ensures that P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs exhibit excellent interface compatibility with the anode and the cathode. The CR2032 button cell Li|P(VEC1-EG0.06)/Pyr0.4/LiTFSI@CE|LiCoO2 demonstrates stable cycling with a negligible capacity decay of 0.083% per cycle for >390 cycles at 25 °C and 0.2 C when using a high-voltage LiCoO2 (4.45 V) cathode. Furthermore, a 7.1 mAh pouch cell achieves stable charge-discharge cycles, confirming the pronounced stability of the as-fabricated QSPE at the interfaces of the high-voltage LiCoO2 cathode and Li anode.

A comprehensive DFT insight on physical features regarding potential applicability of double perovskites K2YCuZ6 (Z = Cl, Br) for energy harvesting applications

Herein, a comprehensive investigation of the structural, mechanical, optoelectronic, and thermoelectric features of K2YCuZ6 (Z = Cl, Br) is presented concerning their potential utilization inphotovoltaic and thermoelectric devices. The observation of formation energy and fitting of the Murnaghan equation of state ensured thermodynamic and structural stability, respectively. The mechanical stability of K2YCuCl6 and K2YCuBr6 is determined by employing Born Huang stability criteria based on their elastic constants. The analysis of elastic parameters further classified these materials as anisotropic as well as ductile. The band gaps of K2YCuCl6 and K2YCuBr6 have been computed using the TB-mBJ potential, resulting in values of 2.4 and 1.56 eV, respectively. An extensive analysis of the optical characteristics of these compounds is carried out in the energy region spanning from 0 to 8 eV. These compounds are discovered to have substantial absorbance and conductive properties in the visible and ultraviolet energy ranges. On the other hand, they exhibit transparency to incoming photons with lower energy levels. Our examination of the optical characteristics indicates that these compounds are very suitable for use in photovoltaic applications. The evaluation of thermoelectric parameters resulted in the p-type semiconducting nature and higher figure of merit of 0.78, and 0.80 at 300 K. Therefore, K2YCuZ6 that has not been verified experimentally has great potential for solar cell and thermoelectric applications, indicating its ability to contribute to the progress of alternative energy sources.

Tuning the physical properties of inorganic novel perovskite materials Ca3PX3 (X=I, Br and Cl): Density function theory

In photovoltaic technology, inorganic perovskite solar cells formed from halide have developed into a noteworthy prospect, primarily attributable to their exceptional efficiency, cost-effectiveness, and straightforward manufacturing techniques. Lead-free A3BX3 inorganic perovskites have generated significant attention within the environmentally friendly solar industry thanks to their extraordinary characteristics encompassing thermoelectricity, optoelectronics, and elasticity. This research focuses on the attributes of the structural, electrical, and optical inorganic halide perovskites Ca3PX3 (X = I, Br, and Cl) using the first-principles density-functional theory (FP-DFT). According to the electronic band structures, Ca3PI3, Ca3PBr3, and Ca3PCl3 show semiconductor characteristics with a straight bandgap of 1.4909 eV, 1.9502 eV, and 2.2058 eV, respectively, at the Γ(gamma)-point. Whenever one takes consideration into account the spin-orbital coupling (SOC) effect, the bandgap of the Ca3PI3, Ca3PBr3, and Ca3PCl3 perovskites is minimized to 1.2382 eV, 1.6456 eV, and 1.9056 eV. All these structures' bandgaps are compressed under compressive strain while they expand with tensile strain. The optical properties indicate that these materials have outstanding visible light consumption capabilities due to their distinct band features, comprising functions of dielectric, consumption coefficient, and function of electron collapse. Observations indicate that the dielectric constant peaks of Ca3PX3 (where X represents I, Br, or Cl) exhibit a redshift, moving towards lower photon energy levels as compressive strain increases. Conversely, they show a blueshift behavior, shifting to a greater amount of photon energy levels by applying tensile strain. Therefore, these characteristics render Ca3PX3 perovskites highly suitable for optimizing light guidance for solar power and energy retention tools.

Surviving at the highest and coldest: Nutritional and chemical components of fallback foods for Yunnan snub-nosed monkeys.

Fallback foods (FBF), categorized into staple and filler types, are suboptimal food sources chosen by animals in response to a scarcity of preferred food items during specific periods. Using lichens as FBF by Yunnan snub-nosed monkeys (Rhinopithecus bieti) represents a distinctive ecological adaptation and evolutionary development within nonhuman primates. This study delves into the annual dietary choices of the species to address issues, elucidate the nutritional value, and understand the ecological significance of lichens for this primate species, which resides at the highest altitudes and experiences the coldest weather among global primates. The findings reveal that the lichens consumed by the monkeys serve as the staple FBF, with Bryoria spp. and Usnea longissima being the primary dietary species. The former is the preferred choice, providing higher digestible fiber (neutral detergent fiber) levels but lower tannin, fat, ADF, and energy levels. During the dry season, lichens dominate as the monkeys' primary food and nutritional resources. In the wet season, they act as a fundamental food selection rather than an ideal dietary choice, substituting nutrients from fruits, seeds, and leaves. Compared to other Asian colobine counterparts, this species exhibits the highest lichen consumption but the lowest proportions of leaves, flowers, and seeds. This study provides valuable evidence and information for developing or amending conservation strategies and guidelines for the dietary management of captive breeding of monkeys, one of the world's critically endangered primate species.

Risk of low energy availability and level of nutrition knowledge in recreational trail runners in Aotearoa/New Zealand

Trail running is an endurance sport growing in popularity. It is characterised by long event durations and extreme environments that are likely to result in high exercise energy expenditure. Energy availability is defined as the amount of energy available to support normal physiological functions after subtracting the energy cost of exercise from energy intake. Insufficient energy intake, increased exercise, or a combination of both can result in a state of low energy availability (LEA). While research shows a weak positive association between nutrition knowledge and diet quality, results are conflicting regarding associations between nutrition knowledge and LEA. Research has demonstrated a high prevalence of risk of LEA (~33%-85%) among both elite and recreational athletes, across both sexes and in endurance sports such as running. However, little is known about risk of LEA and nutrition knowledge in trail runners. The aim of this study was to determine the risk of LEA prevalence in recreational trail runners and investigate associations with nutrition knowledge. Risk of LEA was assessed using the ‘Low Energy Availability in Females Questionnaire’ (LEAF-Q)(1), and the ‘Low Energy Availability in Males Questionnaire’ (LEAM-Q)(2). Nutrition knowledge was measured via the ‘Platform for Evaluating Athlete Knowledge in Sports – Nutrition Questionnaire’ (PEAKS-NQ)(3). Demographics and trail-running experience questions were integrated into the survey. Data was analysed in SPSS version 29 (IBM Corporation). Comparisons between groups (e.g. ‘low risk’ vs ‘not low risk’) were performed using a chi-square test for categorical variables, and an independent samples t-test for continuous variables. The final survey sample was 217 (140 females, 42.01 ± 10.72 years; 77 males, 47.86 ± 12.05 years) for the LEAF-Q, LEAM-Q, and trail running questions; and 152 for the PEAKS-NQ. Thirty-one percent of females (n = 43) were classified as ‘not low risk’ of LEA based on the LEAF-Q cut-off of ≥8. Twenty-three percent of males (n = 18) were identified as having low sex drive, a marker of LEA risk. The LEAF-Q/sex drive score was higher in those ‘not at low risk’ (10.72 ± 2.28/4.50 ± 1.95) compared to those at low risk (3.94 ± 2.34/1.53 ± 1.12, p<0.001). Three quarters of general nutrition knowledge responses were correct (females, 78.60 ± 10.09%; males, 75.78 ± 10.67%). However, sports nutrition scores were lower (females, 66.31 ± 13.44%; males, 63.18 ± 15.53%) with the lowest mean scores observed for ‘fuel for during events’. There was no significant association between nutrition knowledge and risk of LEA in both sexes. The findings suggest that recreational trail runners are a group of active individuals who are at risk of LEA and that they might benefit from more sports-specific nutrition education.

Photon-Counting Detector CT: Potential for 75% Reduction in Contrast Medium Amount: A Phantom Study.

This study aimed to evaluate the potential reduction in contrast medium utilization using photon-counting detector computed tomography (PCD-CT). One PCD-CT scan (CT1) and three conventional (non-PCD-CT) CT scans (CT2-CT4) were performed using a multi-energy CT phantom that contained eight rods with different iodine concentrations (0.2, 0.5, 1, 2, 5, 10, 15, and 20 mg/ml). The CT values of the seven groups (CT1 for 40, 50, 60, and 70 keV; and CT2-4) were measured. Noise and contrast-to-noise ratio (CNR) were assessed for the eight rods at various iodine concentrations. CT2 and CT1 (40 keV) respectively required 20 mg/ml and 5 mg/ml of iodine, indicating that a comparable contrast effect could be obtained with approximately one-fourth of the contrast medium amount. The standard deviation values increased at lower energy levels irrespective of the iodine concentration. The CNR exhibited a decreasing trend with lower iodine concentrations, while it remained relatively stable across all iodine levels (40-70 keV). This study demonstrated that virtual monochromatic 40 keV images offer a similar contrast effect with a reduced contrast medium amount when compared to conventional CT systems at 120 kV.

Dy3+,Mn4+ co-doped phosphors for synergistic luminescent dual-mode thermometer and high-resolution imaging

Fluorescent temperature measurement has become a research hotspot due to its characteristics of non-contact, miniaturization, and fast response. However, it remains a key challenge to realize excellent sensitivity and high resolution. Herein, a series of La2MgTiO6:Dy3+,Mn4+ phosphors are developed and the related energy transfer between Dy3+→Mn4+ is discovered. The coupling distance between Mn4+ and adjacent ligands is greatly affected by temperature. However, the energy differences between the emission energy levels and lower energy levels of Dy3+ hinder the multi-phonon relaxation process, which moderates the thermal quenching rate of Dy3+. Therefore, highly sensitive FIR thermometers are built according to the significant discrimination temperature dependence of Dy3+ and Mn4+. The maximum Sa and Sr reach 0.022 K−1(@563 K) and 2.622 %K−1(@544 K). In contrast, a thermometer based on the emission lifetime of Mn4+ is fabricated, which is extremely sensitive to temperature. Interestingly, Dy3+ can effectively promote the quenching of Mn4+, and then improve the sensitivity. The maximum Sr enhances from 1.621 %K−1(@503 K) to 2.305 %K−1 (@480 K). The high sensitivity and resolution of the dual-mode fluorescence thermometry have exceeded most of the current optical thermal measurement materials. Besides, the thermochromic properties presented by the designed phosphors can be combined with PDMS films to qualitatively evaluate the ambient temperature.

Molecular Simulation Study on the Hydrogen Permeation Behavior and Mechanism of Common Polymers.

This research aimed to provide an understanding of the selection and safe application of pipeline liner materials for hydrogen transport by examining the permeation properties and mechanisms of hydrogen within polymers commonly used for this purpose, such as high-density polyethylene (HDPE) and ethylene-vinyl alcohol copolymer (EVOH), through molecular simulation. The study was carried out within defined operational parameters of temperature (ranging from room temperature to 80 °C) and pressure (from 2.5 to 10 MPa) that are pertinent to hydrogen pipeline infrastructures. The results reveal that with an increase in temperature from 30 °C to 80 °C, the solubility, diffusion, and permeability coefficients of hydrogen in HDPE increase by 18.7%, 92.9%, and 129.0%, respectively. Similarly, in EVOH, these coefficients experience increments of 15.9%, 81.6%, and 112.7%. Conversely, pressure variations have a negligible effect on permeability in both polymers. HDPE exhibits significantly higher hydrogen permeability compared to EVOH. The unique chain segment configuration of EVOH leads to the formation of robust hydrogen bonds among the hydroxyl groups, thereby impeding the permeation of hydrogen. The process by which hydrogen is adsorbed in polymers involves aggregation at low potential energy levels. During diffusion, the hydrogen molecule primarily vibrates within a limited range, with intermittent occurrences of significant hole-to-hole transitions over larger distances. Hydrogen exhibits a stronger interaction with HDPE compared to EVOH, leading to a higher number of adsorption sites and increased hydrogen adsorption capacity in HDPE. Hydrogen molecules move more actively in HDPE than in EVOH, exhibiting greater hole amplitude and more holes in transition during the diffusion process.

The impact of glacial meltwater on the integrated bioenergetic condition of two key antartic benthic polychaetes (Maldane sarsi antarctica, Notomastus latericeus)

In coastal Antarctic environments, glacial meltwater changes the nutrients and physicochemical parameters in the water column. Consequently, top-down cascading effects are triggered throughout the food web, which can affect the bioenergetic condition of benthic invertebrates and their coupling processes between energy levels and flows throughout the marine food web. In this study, two benthic polychaetes (Maldane sarsi antarctica and Notomastus latericeus), exposed to the impact of glacial melting over a broad time scale, were used to evaluate the effect of glacial meltwater on their bioenergetic condition through the integrated analysis of: i) their biochemical composition; ii) fatty acid profiles and iii) total energy contents. The findings indicate that glacial meltwater has a direct effect on the bioenergetic condition of polychaetes. In areas where glacial meltwater has a significant impact, N. latericeus showed higher levels of proteins and glucose, but lower levels of lipids. On the other hand, M. sarsi antarctica exhibited decreased protein content with increasing glacial meltwater impact. M. sarsi antarctica presented varying levels of lipids across different sites, with the highest concentrations observed in areas with moderate impact. Both species showed a reduction in fatty acids with increasing glacial meltwater impact. Additionally, M. sarsi antarctica individuals from highly impacted areas had lower energy levels than those from less impacted areas, while N. latericeus had higher energy levels in the most impacted site. This information enables the development of a framework for assessing the impact of climate change using glacial meltwater and the integrated bioenergetics of key benthic polychaeta as a proxy. Therefore, identifying how glacial meltwater affects their bioenergetic condition helps us understand how climate change could affect trophic interactions, structure, and energy flows in the Antarctic marine food web.

Enhanced Photocatalytic Degradation of Rhodamine B Dye by Iron-Doped Europium Oxide Nanoparticles.

As a wide-bandgap rare-earth oxide, Eu2O3 was often utilized as an auxiliary material of other photocatalysts because its photocatalytic performance was limited by the luminescence characteristics of Eu3+ and low light utilization. In this study, we improved the photocatalytic degradation performance of the Eu2O3 nanoparticles by doping with Fe cations. The Eu2O3 nanoparticles with different Fe-doping concentrations (1, 3, and 5%, noted as EF1.0, EF3.0, and EF5.0, respectively) were synthesized via chemical precipitation and calcination methods. It was found that doping could reduce Eu2O3's bandgap, which probably originated from the introduction of oxygen vacancies with lower energy levels than the conduction band of Eu2O3. Compared with the undoped Eu2O3 nanoparticles with a removal efficiency of 22% for degrading rhodamine B dye within 60 min, the photocatalytic degradation efficiencies of EF1.0, EF3.0, and EF5.0 were demonstrated to be improved to 42, 48, and 33%, respectively, and EF3.0's performance was the best. The enhanced photocatalytic performance of the doped samples was related to the oxygen vacancies acting as capture centers for electrons, such that the photogenerated electron-hole pairs were efficiently separated and the redox reactions on the surface of the nanoparticles were enhanced accordingly. Additionally, the enhanced light absorption and broadened spectral band further improved EF3.0's degradation efficiency.

Regulating the inner Helmholtz plane structure at the electrolyte-electrode interface for highly reversible aqueous Zn batteries

The development of aqueous Zn batteries is limited by parasitic water reactions, corrosion, and dendrite growth. To address these challenges, an inner Helmholtz plane (IHP) regulation method is proposed by employing low-cost, non-toxic maltitol as the electrolyte additive. The preferential adsorption behavior of maltitol can expel the water from the inner Helmholtz plane, and thus hinder the immediate contact between Zn metal and H2O. Meanwhile, strong interaction between maltitol and H2O molecules can restrain the activity of H2O. Besides, the “IHP adsorption effect” along with the low LUMO energy level of maltitol-CF3SO3- can promote the in-situ formation of an organic–inorganic complex solid electrolyte interface (SEI) layer. As a result, the hydrogen/oxygen evolution side reaction, corrosion, and dendrites issues are effectively suppressed, thereby leading to highly reversible and dendrite-free Zn plating/stripping. The Zn||I2 battery with hybrid electrolytes also demonstrates high electrochemical performance and ultralong cycling stability, showing a capacity retention of 75% over 20000 charge-discharge cycles at a large current density of 5 A g−1. In addition, the capacity of the device has almost no obvious decay over 20000 cycles even at −30 °C. This work offers a successful electrolyte regulation strategy via the IHP adsorption effect to design electrolytes for high-performance rechargeable Zn-ion batteries.