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Oxygen defects are introduced into PbZr0.5Ti0.5O3 films and their impact on ferroelectric behavior, linear dielectric response (LDR), and nonlinear dielectric response (NDR) is studied. Apart from a notable decrease in both polarization and LDR permittivity, the frequency spectra of LDR exhibit a distinctive loss peak. The peak position varies with temperature and oxygen defect concentration. NDR parameters, including the Rayleigh coefficient (α1), the slope (α2) correlating the imaginary part of permittivity with the ac electric field, and the slope (k) between the real and the imaginary parts of permittivity, demonstrate diverse behaviors in response to temperature and oxygen defect concentration. The similarity in the frequency spectra of tanδ and 1/k reveals the correlation between LDR and NDR induced by the presence of oxygen defects. These observations are attributed to the behavior of the single and composite defects associated with oxygen vacancies. [ABSTRACT FROM AUTHOR]

A fundamental equation of state in terms of the Helmholtz energy is presented for mixtures of nitrogen, oxygen, and argon at any composition. It is expressed in terms of the residual Helmholtz energy and can be used to calculate all thermodynamic equilibrium properties including vapor–liquid equilibria. The parameters of the equations for the pure-fluid and mixture contributions are fitted exclusively to molecular simulation data so that the model has a predictive character. The description of the mixture-specific reducing parameters is realized via generalized correlations of the critical parameters of the pure fluids so that an extension of the model to additional components can be implemented straightforwardly. Extensive comparisons to experimental data and the GERG-2008 reference equation of state show that the prediction of thermodynamic properties is satisfactory. [ABSTRACT FROM AUTHOR]

We present a method by which the direct detection effect in superconducting hot-electron bolometer mixers can be analytically accounted for with sufficient practical accuracy. This is achieved by means of the advanced uniform, non-linear two-temperature model that considers the effective temperatures of electrons and phonons alongside established material parameters. We demonstrate the efficacy of this approach for the ex situ correction of the radiance of the emission line of atomic oxygen under conditions when the direct detection causes a 30% error in the line magnitude. The correction was applied to data collected by a balloon-borne heterodyne receiver operating in the upper atmosphere of Earth. The corrected line shape and magnitude are in reasonable agreement with the predictions of atmospheric radiation transfer models. [ABSTRACT FROM AUTHOR]

Scandium nitride (ScN) is an attractive material for electronic applications due to its high n -type conductivity. Native defects and unintentional impurities may limit its electron concentration and reduce its mobility; therefore, it is important to control their formation and incorporation. Hydrogen and oxygen are unintentional impurities that are commonly present during growth and processing. They act as shallow donors in ScN and hence may be regarded as harmless or even favorable to achieving n -type conductivity. Here we show, using state-of-the-art first-principles calculations, that these impurities can be detrimental because they readily form complexes with scandium vacancies (V Sc ). Isolated V Sc have relatively high formation energies and thus have low concentrations and little impact on electronic properties. However, complexes between V Sc and either hydrogen or oxygen form more readily than the pristine vacancy and will act as both compensating and scattering centers. Our results point to the importance of controlling the incorporation of hydrogen and oxygen in ScN (and AlScN alloys) to avoid degradation of the electronic properties. [ABSTRACT FROM AUTHOR]

In this work, bottom-Schottky-structure InGaZnOx (IGZO) Schottky barrier diodes (SBDs) with sputtered PtOx anodes were fabricated and annealed in oxygen at different temperatures. Critical parameters and negative bias stress (NBS) stability of SBDs with different annealing temperatures are investigated. With the annealing temperature increases, the barrier height and rectification ratio of the SBDs exhibited a rising-then-declining trend, while the ideality factor slightly increased until 200 °C. The SBDs show up overall reliability except for a leakage current rising trend under light, which can be attributed to free electron generation from the ionized oxygen vacancy. Among all the SBDs, the 175 °C annealed ones exhibited the best overall performance, including a high barrier height of 0.89 eV, an ideality factor of 1.14, and a large rectification ratio of over 108. Compared to the initial SBDs, the annealed ones showed up great improvement in NBS stability except for the 200 °C annealed ones, which was permanently degraded and not able to recover to original states. According to experimental result analysis and IGZO material characteristics, a stability model based on the subgap trap transition from V O 2 + to VO and new V O 2 + creation was proposed, which applies to both the short-term and long-term NBS tests. The results above demonstrate that oxygen annealing at appropriate temperature is an effective method to improve both device performance and NBS stability for PtOx–IGZO SBDs. [ABSTRACT FROM AUTHOR]

This study analyzes the regulatory mechanism of oxygen vacancy concentration on tail-to-tail charged domain walls (T–T CDWs), along with the writing time, conduction current magnitude, and retention performance of through-type T–T CDWs. The research results show that the highest density and length of T–T CDWs are achieved when the oxygen vacancy concentration is 1 × 1020 cm−3. Moreover, the successful writing of through-type T–T CDWs is limited to a certain electric field range, which is controlled by oxygen vacancy concentration. An increase in the oxygen vacancy concentration leads to a decrease in the maximum and minimum threshold electric fields required for writing through-type charged domain walls. The writing time and conductivity of through-type T–T CDWs determine the information writing speed and signal strength of domain wall memories, and the oxygen vacancy concentration also plays a regulatory role in both aspects. When the oxygen vacancy concentration is 1 × 1020 cm−3, the through-type T–T CDW exhibits the fastest writing speed, requiring only 8 ns. The magnitude of the conduction current of through-type T–T CDWs is directly proportional to the oxygen vacancy concentration. The through-type T–T CDWs formed by the aggregation of oxygen vacancies exhibit excellent retention performance, making them highly promising for applications in ferroelectric domain wall memories. Our research demonstrates that oxygen vacancies have a significant regulatory effect on the morphology and current response of charged domain walls, opening up new avenues for the study of domain wall memories. [ABSTRACT FROM AUTHOR]

In view of the inherent pseudocapacitance, rich redox pairs (Nb5+/Nb4+ and Nb4+/Nb3+), and high lithiation potential (1.0–3.0 V vs Li/Li+), Nb2O5 is considered a promising anode material. However, the inherent low electronic conductivity of Nb2O5 limits its lithium storage performance, and the rate performance after carbon modification is still unsatisfactory because the intrinsic conductivity of Nb2O5 has not been substantially improved. In this experiment, taking the improvement of the intrinsic electrical conductivity of Nb2O5 as the guiding ideology, we prepared F-doped Nb2O5@fluorocarbon composites (F–Nb2O5@FC) with a large number of oxygen vacancies by one-step annealing. As the anode electrode of lithium-ion batteries, the reversible specific capacity of F–Nb2O5@FC reaches 150 mA g−1 at 5 A g−1 after 1100 cycles, and the rate performance is particularly outstanding, with a capacity up to 130 mA g−1 at 16 A g−1, which is far superior to other Nb2O5@carbon-based anode electrodes. Compared with other single conductivity sources of Nb2O5@carbon-based composites, the electrical conductivity of F–Nb2O5@FC composites is greatly improved in many aspects, including the introduction of free electrons by F− doping, the generation of oxygen vacancies, and the provision of a three-dimensional conductive network by FC. Through analytical chemistry (work function, UV–Vis diffuse reflectance spectroscopy, and EIS) and theoretical calculations, it is proved that F–Nb2O5@FC has high electrical conductivity and realizes rapid electron transfer. [ABSTRACT FROM AUTHOR]

Amorphous ice phases are key constituents of water's complex structural landscape. This study investigates the polyamorphic nature of water, focusing on the complexities within low-density amorphous ice (LDA), high-density amorphous ice, and the recently discovered medium-density amorphous ice (MDA). We use rotationally invariant, high-dimensional order parameters to capture a wide spectrum of local symmetries for the characterization of local oxygen environments. We train a neural network to classify these local environments and investigate the distinctiveness of MDA within the structural landscape of amorphous ice. Our results highlight the difficulty in accurately differentiating MDA from LDA due to structural similarities. Beyond water, our methodology can be applied to investigate the structural properties and phases of disordered materials. [ABSTRACT FROM AUTHOR]

Reliable nanoswitch operation requires low contact voltages and stable electrical contact resistance (E C R). Surface cleanliness is crucial to prevent nanomechanical switch failure, which can occur due to the presence of insulating adventitious hydrocarbon films. In situ O2 plasma cleaning is effective but oxidizes metal surfaces. Here, the noble metal Pt, which forms PtOx, is employed to form electrodes. Previous studies report on PtOx electrical resistivity, but the effects of PtOx evolution at contacting interfaces due to electrical and mechanical stimuli have not been explored. This study investigates the impact of PtOx on E C R at low contact voltages under hot switching, cold switching, and mechanical cycling conditions. An increase in E C R upon plasma cleaning indicates the presence of a resistive PtOx layer. After hot and cold switch cycling at applied voltages of 300 mV or less, a low stable E C R is achieved. A higher contact voltage accelerates E C R stabilization. The results are consistent with PtOx film volatilization, which is primarily due to Joule heating rather than mechanical rupture. This investigation advances the understanding of interface evolution in plasma-cleaned nanoswitches. [ABSTRACT FROM AUTHOR]

Accurate Force Fields (FFs) are essential for Molecular Dynamics (MD) simulations of the dynamics of realistic materials in terms of atomic-level interactions. The FF parameters of short-range valence interactions can be derived through Quantum Mechanical (QM) calculations on model systems practical for QM (<300 atoms). Similarly, the dynamic electrostatic interactions can be described with methods such as QEq or PQEq that allow charges and polarization to adjust dynamically. However, accurately extracting long-range van der Waals (vdW) interactions from QM calculations poses challenges due to the absence of a definitive method to distinguish between the different energetic components of electrostatics, polarization, vdW, hydrogen bonding, and valence interactions. To do this we use the Perdew–Burke–Ernzerhof flavor of Density Functional Theory, including empirical D3 vdW corrections, to predict the Equation of State for each element (keeping any covalent bonds fixed), from which we obtain the two-body vdW nonbond potential. Here, we extend these calculations to include non-bonded parameters for the N and O columns of the periodic table so that we now describe columns 15 (N), 16 (O), 17 (F), and 18 (Ne) of the periodic table. For these 20 elements, we find that the two-body vdW potentials can all be mapped to a single universal two-body curve, with just three scaling parameters: Re, De, and L. We refer to this as the Universal NonBond (UNB) potential. We expect this to be useful for new MD simulations and a helpful starting point to obtain UNB parameters for the remainder of the periodic table. [ABSTRACT FROM AUTHOR]

We present theory and a simulation framework to model three-body collisions and gas phase recombination in dilute atom/diatom mixtures of pure oxygen (O/O2) and nitrogen (N/N2) using the Quasi-Classical Trajectory method. We formulate a three-body collision rate constant based on the lifetimes of binary collisions and initialize three-body collisions by sampling the arrival time of a third body within the lifetimes of pre-simulated binary collisions. We use this method to calculate distributions of recombined product energies, probabilities of recombination, and recombination rate constants through different collision pathways. Long-lived binary atom-diatom collisions are observed, but are too rare to play a dominant role in the recombination process for shock-heated air near the equilibrium conditions studied. The resulting recombination rate constants are within an order of magnitude of the predictions of detailed balance. Notably, the recombination simulation framework does not appeal to the principle of detailed balance and could be useful for studying conditions far from equilibrium. [ABSTRACT FROM AUTHOR]

The demand for reliable memory devices capable of operating in harsh environments, such as space and vehicles, necessitates the development of high-temperature-resistant technologies. In this study, we propose a novel ferroelectric domain wall (DW) memory utilizing BiFeO3 thin films, which exhibit exceptional retention and fatigue properties at 135 °C. Achieving this performance was made possible through precise control of the oxygen vacancy density in the epitaxial thin films induced by a post-annealing procedure conducted under an appropriate oxygen pressure of 10 Pa. Initially, prototype nano-memory devices lacking post-annealing treatment demonstrated resistive switching behavior at room temperature, with a current rectification ratio of 100:1, achieved by manipulating the uncompensated DW induced by polarization switching. With the additional annealing procedure in lower oxygen pressure, the wall current magnitude of the devices increased significantly, indicating the critical role of the oxygen vacancies in modulating the DW conductivity. Moreover, the nanodevices exhibited improved polarization retention due to oxygen vacancy-mediated charge injection that can be further enhanced at the elevated temperature. The electrons trapped deeply at the artificial DW were found to stabilize the switched polarization at the expense of reduced DW conductivity, emphasizing the importance of precise control over oxygen vacancy density for achieving a balance between high DW conductivity and excellent polarization retention. [ABSTRACT FROM AUTHOR]

In this work, the effects of cerium doping and oxygen defects of ferroelectric Hf0.5Zr0.5O2 (HZO) are systematically studied by first-principles calculations. According to the results, the combined effect of Ce atoms and oxygen vacancy has a significant effect on the improvement of the orthorhombic phase fraction in HZO, and the mechanism of this phenomenon is also studied. The optimal concentration of Ce doping is 9.375 formula unit%, and the optimal concentration of oxygen vacancy is 9.375 formula unit%. The interaction between Ce doping and oxygen defects is also discussed from the perspective of structural stability and electrical balance. These findings are helpful for the preparation of Ce-doped HZO ferroelectric thin films and provide experience for the study of other dopants. [ABSTRACT FROM AUTHOR]

In this work, we studied the impact of environmental constituents such as oxygen (O2) and moisture on halide double perovskite (HDP) films. The transport measurements indicate that an increment in O2 concentration enhances the resistivity of a Cs2AgBiBr6 film by two orders of magnitude. The adsorption of O2 on the film's surface helps in passivation of defects (∼50% reduction in defect density on O2 exposure), which inhibits ion migration and results in an increased resistivity of the film. The process of adsorption and desorption of O2 on the film surface is found to be fully reversible. In contrast, the resistivity of double perovskite films decreases by an order of magnitude in the presence of moisture. This is attributed to the generation of free protons as a result of the dissociation of water molecules at the films' surface, hence exhibiting an increase in current under external bias. The HDP films possess high resistivity (for T < 100 °C) due to the desorption of physisorbed water layers from the surface, which gradually decreases with an increase in the operating temperature. This work demonstrates that O2 and moisture are a good combination for defect passivation in any HDPs, in general. [ABSTRACT FROM AUTHOR]

La-doped BaSnO3 (BLSO) exhibits promising applications in oxide electronic devices, owing to its high electron mobility and good thermal stability. The introduction of extrinsic La dopants could actively interact with the formation of intrinsic oxygen vacancies in BLSO films, which collectively influence the resulting transport behavior. However, it is not clear which factor plays a dominant role when the La dopant ratio varies. Here, we fabricate BLSO films at lightly doped (0.2%) and heavily doped (7%) regimes and perform a systematic investigation on the oxygen vacancy impact on structure, optical, and transport properties of these BLSO films. It is revealed that the BLSO films grown at an ozone environment show larger strain and lower oxygen vacancy concentrations for all investigated dopant ratios. More importantly, the introduction of ozone decreases the mobility and the carrier concentration of both lightly doped and heavily doped films. This study reveals that the presence of oxygen vacancies enhances the carrier concentration and electron mobility, which is independent of the La dopant ratio, and provides an effective strategy for optimizing the electrical properties of BLSO films. [ABSTRACT FROM AUTHOR]

In this manuscript, perovskite oxide LaCoO3/LaMnO3/LaCoO3 (LLL) trilayers and the single-layer LaMnO3 (LMO) and LaCoO3 (LCO) films are epitaxially grown on (001)-oriented SrTiO3 substrates by polymer-assisted deposition combining with heat treating in Ar, air, and O2 atmospheres, respectively. The crystal structure and magnetic properties are investigated. It is found that the responses of LMO and LCO films to oxygen content are different, and the magnetic property of LMO is more sensitivity to oxygen content than that of LCO. The oxygen content can directly affect the structure and magnetic properties of LMO and LCO layers, which, in turn, modulate the interfacial magnetic properties of the LLL trilayers through interlayer coupling. By comparison with the magnetic properties of the single-layer films, an abnormal ferromagnetic (FM) transition is found in the LLL trilayers at around 216 K, besides two known FM transitions corresponding to those in the LCO and LMO layers, respectively. It is suggested that the abnormal FM transition is attributed to Mn4+–O–Co2+ FM super-exchange interaction, which is induced by the charge transfer from Mn3+ to Co3+ ions and the interlayer coupling between the LMO and LCO layers. The interlayer coupling of the trilayers, including the interfacial coupling and the diffusion-induced inlayer coupling, dominates the interface properties, which are tuned by oxygen content-dependent charge transfer. The cooperative function of the orbital/charge structure and the interlayer coupling dominates the magnetic properties of the LLL trilayer under the tensile strain. These findings provide new avenues to regulate the electronic and magnetic states of perovskite oxide multilayers and another way to the development of multifunctional electronic devices. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticle (NP) supports of both good conductivity and stability have the potential to enhance both the reaction activity and stability of the loaded electrocatalysts. In this paper, a facile two-step approach to disperse Pt nanoparticles on the surface of an IrO2 NP support (Pt/IrO2) was developed. Physical characterization by x-ray diffraction spectroscopy and transmission/scanning electron microscopy suggests a good dispersion of the Pt NPs. The temperature effect (from 293 to 353 K) of oxygen reduction reaction on Pt/IrO2 was studied by using a rotating ring disk electrode The results show that although the kinetic current density on Pt/IrO2 is close to that on commercial Pt/C at room temperature, the apparent activation energy (Ea,app) in the former case is much lower, suggesting a much higher activity at elevated temperatures. The superiority in Ea,app is attributed to the electron interaction between Pt and the IrO2 support, as supported by the change of surface chemical state given by x-ray photo-electron spectroscopy. [ABSTRACT FROM AUTHOR]

Titanium oxide (TiO2) coated polyimide has broad application prospects under extreme conditions. In order to obtain a high-quality ultra-thin TiO2 coating on polyimide by atomic layer deposition (ALD), the polyimide was activated by in situ oxygen plasma. It was found that a large number of polar oxygen functional groups, such as carboxyl, were generated on the surface of the activated polyimide, which can significantly promote the preparation of TiO2 coating by ALD. The nucleation and growth of TiO2 were studied by x-ray photoelectron spectroscopy monitoring and scanning electron microscopy observation. On the polyimide activated by oxygen plasma, the size of TiO2 nuclei decreased and the quantity of TiO2 nuclei increased, resulting in the growth of a highly uniform and dense TiO2 coating. This coating exhibited excellent resistance to atomic oxygen. When exposed to 3.5 × 1021 atom cm−2 atomic oxygen flux, the erosion yield of the polyimide coated with 100 ALD cycles of TiO2 was as low as 3.0 × 10−25 cm3/atom, which is one order less than that of the standard POLYIMIDE-ref Kapton® film. [ABSTRACT FROM AUTHOR]

The evolution of oxygen evolution reaction (OER) remains a pivotal challenge in the realm of oxygen electrocatalysis. Recently, the proposition of regulating spin states has emerged as a novel avenue for enhancing the efficiency of electrocatalytic reactions. Presently, accurately modulating the metal active center into immediate spin (IS) remains a formidable challenge. Here, our research has achieved a breakthrough in precise spin state control and catalytic performance enhancement of Co3+ through the utilization of Ni-substituted LaCo 1- x Ni x O 3 perovskite. This achievement is primarily attributed to the fine regulation of both the secondary coordination sphere (SCS) and primary coordination sphere (PCS), i.e., Co 6- y -[Co]-Ni y (y = 0–6) and Co-O lengths, respectively. Our findings reveal that LaCo 7/9 Ni 2/9 O 3 consisted of the SCS (y ≤ 2) with the e g 1 fillings of IS Co3+ exhibits an optimal OER activity. Additionally, adjusting the Co-O bond length in PCS to approximately 1.89 Å proves to be more conducive to the transition of Co3+ spin states from high spin (HS) and low spin (LS) to IS. These discoveries present new approach to precisely modulating the spin state, offering promising prospects for the development of high-efficiency OER catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] Developing multi-functional electrocatalysts is of great practical significance for fuel cells and water splitting. Herein, Rh-Rh 2 O 3 nanoclusters are prepared and the surface oxygen vacancy content is regulated elaborately by post-treatment. The optimized Rh-Rh 2 O 3 /C-400 exhibits superior trifunctional catalytic activity for hydrogen oxidation reaction (HOR), hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR), i.e., the mass activity for HOR is 2.29 mA μg Rh -1, and the overpotential for HER and HzOR at 10 mA cm−2 is as low as 12 mV and 31 mV, respectively, superior to the benchmark Pt/C. Rh-Rh 2 O 3 /C-400 also displays promising performance in practical devices, with the H 2 -O 2 anion-exchange-membrane fuel cell delivering a peak power density of 0.66 W cm−2, and the hydrazine-assisted water splitting electrolyzer requiring a low electrolysis voltage of 0.161 V at 0.1 A cm−2. The experimental and theoretical investigations discover that the hydrogen binding energy (HBE) is linearly depended on surface oxygen vacancy contents, and the HBE directly determines the catalytic activity for HOR, HER and HzOR. This work not only innovates an efficient Rh-based nanocluster tri-functional electrocatalyst, but also eludicates the intrinsic relationship of surface structure-intermediate adsorption-catalytic activity. [ABSTRACT FROM AUTHOR]

A heterostructured Co-based electrocatalyst is successfully synthesized using bifunctional ligand Co metal–organic frameworks as precursors. The bifunctional ligands provide enough N and O atoms that can simultaneously convert Co ions into CoN x moieties, Co nanoparticles and Co oxides via one-step pyrolysis. The obtained electrocatalysts with heterostructured CoO x /Co nanoparticles encapsulated by porous conductive carbon rich in CoN x active sites deliver remarkable oxygen reduction reaction and oxygen evolution reaction activities. With the synergistic effects among these multifunctional components, a rechargeable zinc–air battery built with this electrocatalyst exhibits a high-power density and long-lasting rechargeability. [Display omitted] Rational construction of efficient and robust bifunctional oxygen electrocatalysts is key but challenging for the widespread application of rechargeable zinc-air batteries (ZABs). Herein, bifunctional ligand Co metal–organic frameworks were first explored to fabricate a hybrid of heterostructured CoO x /Co nanoparticles anchored on a carbon substrate rich in CoN x sites (CoO x /Co@Co N C) via a one-step pyrolysis method. Such a unique heterostructure provides abundant CoN x and CoO x /Co active sites to drive oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively. Besides, their positive synergies facilitate electron transfer and optimize charge/mass transportation. Consequently, the obtained CoO x /Co@Co N C exhibits a superior ORR activity with a higher half-wave potential of 0.88 V than Pt/C (0.83 V vs. RHE), and a comparable OER performance with an overpotential of 346 mV at 10 mA cm−2 to the commercial RuO 2. The assembled ZAB using CoO x /Co@Co N C as a cathode catalyst displays a maximum power density of 168.4 mW cm−2, and excellent charge–discharge cyclability over 250 h at 5 mA cm−2. This work highlights the great potential of heterostructures in oxygen electrocatalysis and provides a new pathway for designing efficient bifunctional oxygen catalysts toward rechargeable ZABs. [ABSTRACT FROM AUTHOR]

By a two-step method, we successfully synthesized a WS 2 /WO 3-x heterostructured catalysts with abundant oxygen vacancies. The WS 2 /WO 3-x -2 heterostructured catalyst demonstrates outstanding HER activity and stability in acidic and alkaline electrolytes. [Display omitted] H 2 produced through hydrogen evolution reaction (HER) is a shining star in the field of clean energy. Significant efforts have been dedicated to develop efficient and stable electrocatalysts to reduce the energy barrier and accelerate the kinetics of Hydrogen evolution reaction (HER) under various environments. Herein, we propose a strategy to accelerate the kinetics of HER under acid and alkaline environments by combining heterostructure engineering with defect engineering. We have successfully synthesized a series of WS 2 /WO 3-x heterostructured catalysts, accompanied with substantial oxygen vacancies using a two-step synthesis method. With the partially sulfurization of WO 3-x , the heterojunction interface of WS 2 and WO 3-x was formed along with the appearance of oxygen vacancies, which can facilitate the migration of electrons. The heterostructured catalyst enriched with oxygen vacancies (defined as WS 2 /WO 3-x -2) demonstrates superior HER performance in acidic and alkaline electrolytes. At a current density of 10 mA cm−2, the WS 2 /WO 3-x -2 heterostructured catalyst manifests an overpotential of 120 mV in the acidic electrolytes and a slightly higher overpotential of 150 mV in an alkaline environment. The overpotentials offer an improvement compared to reported W-based catalysts in terms of HER performance. This work provides guiding significance on the design of heterostructured catalysts with promising performance for HER in acidic and alkaline environments. [ABSTRACT FROM AUTHOR]

Monoclinic Nb 2 O 5 (H–Nb 2 O 5) as an prospect anode material for lithium ion batteries due to its high theoretical specific capacity of 250 mAh g-1 and a safe working voltage in the range of 1–3 V, but the inherent low electron conductance greatly limits its high-rate performance. In this paper, we synthesized F-doped Nb 2 O 5 with S/F co-doped carbon composites (F–Nb 2 O 5 @SFC) by simple high-temperature annealing method, XPS and EPR analysis results show that the composites has abundant of oxygen vacancies. Under the dual effects of F− doping and oxygen vacancy, the free electron concentration of Nb 2 O 5 structure is greatly increased, and the conductive network provided by SFC accelerates the electron transport process, thus, the obtained F–Nb 2 O 5 @SFC material achieves excellent conductivity. In addition, the charge density difference results indicate that the unbalanced charge distribution around oxygen vacancies provides additional Li+ active sites, and the constructed electric field accelerates the transmission of Li+. The fast Li+/electron transfer kinetics of the F–Nb 2 O 5 @SFC electrode has achieved excellent storage performance, with a reversible specific capacity of 165 mAh g-1 at 1A g-1 after 600 cycles and a high-rate capacity of 130 mAh g-1 at 10A g-1. [ABSTRACT FROM AUTHOR]

Owing to the energy-efficient attributes of electrochromic technology, there has been a growing emphasis on the fabrication of electrochromic devices with high-contrast and stable performance. As an electron donor, the deliberate incorporation of oxygen vacancies into an electrochromic material is poised to significantly elevate the film's electrochromic characteristics. In this study, we successfully synthesized one-dimensional W 18 O 49 nanowires thin films with enhanced oxygen vacancies using a straightforward combination of solvothermal reactions and annealing in Ar. In comparison to films annealed in air, those treated in argon (Ar) exhibited a higher concentration of oxygen vacancies, resulting in improved light absorption characteristics. The optimal annealing conditions were determined to be 400 °C for 40 min. Under these conditions, the thin film demonstrates enhanced electrochromic performance, exhibiting a notable 71.6% modulation in transmittance, a 27.2% increase compared to the air condition. It displays a rapid response time (T b = 3.3 s, T c = 3 s), high coloration efficiency (CE = 55.9 cm2 C−1), and excellent cycling stability (with a ΔT retention rate of 93.9% after 750 cycles). [ABSTRACT FROM AUTHOR]

This study focuses on developing a LOX-compatible PMC material by enhancing its thermal conductivity. An innovative technique involving the integration of high thermally conductive carbon nanotubes (CNTs) onto carbon fibers (CF) was employed, followed by impregnation with cyanate ester (CE) resin. The LOX compatibility of CE resin-only, CF impregnated with CE resin (CF/CE), and the proposed CNT-modified CF composite (CNTs-CF/CE) was investigated according to ASTM D2512 guidelines. While the CE resin-only samples exhibited no reaction, CF/CE and CNTs-CF/CE composites reacted with a flash event during the LOX compatibility test. Further investigation revealed that the introduction of CNTs in the CF/CE composite increased the LOX reaction probability. Notably, the study identified the influence of the damage level on the ignition rate, emphasizing the importance of damage assessment. These findings underscore the potential of CNTs in enhancing LOX compatibility and contribute valuable insights toward the development of efficient LOX storage tank applications. [ABSTRACT FROM AUTHOR]

Background and Objective: Interstitial lung disease (ILD) is characterized by dyspnoea on exertion and exercise‐induced hypoxaemia. High‐flow nasal cannula (HFNC) therapy reduces the respiratory workload through higher gas flow and oxygen supplementation, which may affect exercise tolerance. This study aimed to examine the effects of oxygen and gas flow rates through HFNC therapy on exercise tolerance in ILD patients. Methods: We conducted three‐treatment crossover study. All ILD patients performed the exercises on room air (ROOM AIR setting: flow, 0 L/min; fraction of inspired oxygen [FiO2], 0.21), HFNC (FLOW setting: flow 40 L/min, FiO2 0.21), and HFNC with oxygen supplementation (FLOW + OXYGEN setting: flow 40 L/min, FiO2 0.6). The primary endpoint was the endurance time, measured using constant‐load cycle ergometry exercise testing at a peak work rate of 80%. Results: Twenty‐five participants (10 men, 71.2 ± 6.7 years) were enrolled. The increase in exercise duration between the ROOM AIR and FLOW was 46.3 s (95% CI, −6.1 to 98.7; p = 0.083), and the FLOW and FLOW + OXYGEN was 91.5 s (39.1–143.9; p < 0.001). The percutaneous oxygen saturation (SpO2) at rest was significantly higher with the FLOW + OXYGEN setting than with the ROOM AIR and FLOW settings, and the difference persisted during exercise. At equivalent time points during exercise, the SpO2 with the FLOW setting was significantly higher than that with the ROOM AIR setting. Conclusion: Oxygen supplementation in HFNC therapy improved exercise tolerance and SpO2. We found that gas flow alone did not improve exercise tolerance, but improved SpO2 during exercise. [ABSTRACT FROM AUTHOR]

Background and Aims Internal root aeration is essential for root growth in waterlogged conditions. Aerenchyma provides a path for oxygen to diffuse to the roots. In most wetland species, including rice, a barrier to radial oxygen loss (ROL) allows more of the oxygen to diffuse to the root tip, enabling root growth into anoxic soil. Most dryland crops, including barley, do not form a root ROL barrier. We previously found that abscisic acid (ABA) signalling is involved in the induction of ROL barrier formation in rice during waterlogging. Although rice typically does not form a tight ROL barrier in roots in aerated conditions, an ROL barrier with suberized exodermis was induced by application of exogenous ABA. Therefore, we hypothesized that ABA application could also trigger root ROL barrier formation with hypodermal suberization in barley. Methods Formation of an ROL barrier was examined in roots in different exogenous ABA concentrations and at different time points using cylindrical electrodes and Methylene Blue staining. Additionally, we evaluated root porosity and observed suberin and lignin modification. Suberin, lignin and Casparian strips in the cell walls were observed by histochemical staining. We also evaluated the permeability of the apoplast to a tracer. Key Results Application of ABA induced suberization and ROL barrier formation in the adventitious roots of barley. The hypodermis also formed lignin-containing Casparian strips and a barrier to the infiltration of an apoplastic tracer (periodic acid). However, ABA application did not affect root porosity. Conclusions Our results show that in artificial conditions, barley can induce the formation of ROL and apoplastic barriers in the outer part of roots if ABA is applied exogenously. The difference in ROL barrier inducibility between barley (an upland species) and rice (a wetland species) might be attributable to differences in ABA signalling in roots in response to waterlogging conditions. [ABSTRACT FROM AUTHOR]

Summary: High‐flow nasal oxygen can be administered at induction of anaesthesia for the purposes of pre‐oxygenation and apnoeic oxygenation. This intervention is claimed to enhance carbon dioxide elimination during apnoea, but the extent to which this occurs remains poorly quantified. The optimal nasal oxygen flow rate for gas exchange is also unknown. In this study, 114 patients received pre‐oxygenation with high‐flow nasal oxygen at 50 l.min‐1. At the onset of apnoea, patients were allocated randomly to receive one of three nasal oxygen flow rates: 0 l.min‐1; 70 l.min‐1; or 120 l.min‐1. After 4 minutes of apnoea, all oxygen delivery was ceased, tracheal intubation was performed, and oxygen delivery was recommenced when SpO2 was 92%. Mean (SD) PaCO2 rise during the first minute of apnoea was 1.39 (0.39) kPa, 1.41 (0.29) kPa, and 1.26 (0.38) kPa in the 0 l.min‐1, 70 l.min‐1 and 120 l.min‐1 groups, respectively; p = 0.16. During the second, third and fourth minutes of apnoea, mean (SD) rates of rise in PaCO2 were 0.34 (0.08) kPa.min‐1, 0.36 (0.06) kPa.min‐1 and 0.37 (0.07) kPa.min‐1 in the 0 l.min‐1, 70 l.min‐1 and 120 l.min‐1 groups, respectively; p = 0.17. After 4 minutes of apnoea, median (IQR [range]) arterial oxygen partial pressures in the 0 l.min‐1, 70 l.min‐1 and 120 l.min‐1 groups were 24.5 (18.6–31.4 [12.3–48.3]) kPa; 36.6 (28.1–43.8 [9.8–56.9]) kPa; and 37.6 (26.5–45.4 [11.0–56.6]) kPa, respectively; p < 0.001. Median (IQR [range]) times to desaturate to 92% after the onset of apnoea in the 0 l.min‐1, 70 l.min‐1 and 120 l.min‐1 groups, were 412 (347–509 [190–796]) s; 533 (467–641 [192–958]) s; and 531 (462–681 [326–1007]) s, respectively; p < 0.001. In conclusion, the rate of carbon dioxide accumulation in arterial blood did not differ significantly between apnoeic patients who received high‐flow nasal oxygen and those who did not. [ABSTRACT FROM AUTHOR]

The corrosion behavior of the aluminum-alloyed austenitic steels Fe-18Ni-12Cr-2.9Al and Fe-18Ni-12Cr-2.3Al-Nb-C was investigated at 700 °C in static Pb for 1000 h as a function of the concentration of dissolved oxygen in the liquid metal. In Pb with ~ 5 × 10–9 mass % dissolved oxygen, both steels showed dissolution. Depth of corrosion averaged 67 (± 18) µm and 78 (± 25) µm for Fe-18Ni-12Cr-2.3Al-Nb-C and Fe-18Ni-12Cr-2.9Al, respectively. In Pb with higher oxidation potential of 2 × 10–6 mass %O, both steels showed protective and accelerated oxidation. The protective thin oxide film (≤ 1 µm) was composed of outermost Fe-rich, intermediate Cr-rich and inner Al-rich sublayers. The thicker oxide scale was of irregular thickness (2 ÷ 30 µm) and consisted of Fe–Cr mixed oxide with Ni-rich metallic inclusions. [ABSTRACT FROM AUTHOR]

Professor George Smelser was a scientist who played a crucial role in advancing the understanding of the anatomical and physiological changes within the cornea during contact lens wear. In a series of unique experiments conducted in the early 1950s, using both humans and animal models, his research team provided the first conclusive evidence that contact lenses impaired the delivery of atmospheric oxygen to the cornea, resulting in an excess of lactate within the cornea and a subsequent ingress of water, leading to corneal oedema and disturbed vision (Sattler's veil). This historical note reviews the career of George Smelser, with particular emphasis on his contributions to understanding the importance of atmospheric oxygen in maintaining corneal homeostasis. [ABSTRACT FROM AUTHOR]

In urban drainage systems, falling sewage in drop structures expedites the mass transfer of hydrogen sulfide (H2S) and oxygen (O2). This process is important for sewer odor and corrosion control; however, direct experiments and relevant knowledge are limited. This study conducted laboratory experiments using two typical forms of falling sewage: free-falling jet and attached-falling jet. The results show that mass transfer coefficient KL and concentration deficit ratio r (the ratio of upstream-to-downstream gas concentration deficiency) increase with an increase of sewage drop height (0.2–1.4 m) and with a decrease of flow rate (0.9–2.0 L/min). Nonlinear correlations between r and the hydraulic parameters were proposed. The free-falling jet contributed about 40% more mass transfer than the attached-falling jet. The mass transfer rate in free-falling drop structures of this study was 3–13 times that in gravity sewers without drop structures. In addition, O2 is an appropriate surrogate gas for studying H2S mass transfer. Finally, the mass transfer of O2 in a prototype drop structure was estimated: if the drop height is <3 m , the jet may not break up, the mass transfer at the jet surface can be neglected, and almost all the mass transfer happens at the bottom pool of the drop structure; however, if the drop height is >6 m , falling droplets are the main (>80%) contributor. This study provides a tool for estimating the mass transfer in drop structures, which can optimize the design of drop structures to control sewer odor and pipe corrosion. [ABSTRACT FROM AUTHOR]

Surface structure and relevant oxygen vacancy play an important role in the application of RE2Si2O7 for environmental barrier coatings, in which the oxygen vacancies in RE2Si2O7 may influence their thermal and optical properties. In this work, the structure and thermodynamics of (0 0 1) and (1 1 0) surfaces of RE2Si2O7 (RE = Yb, Lu) are studied via first‐principles calculations to reveal the underlying mechanism of the surface formation and the associated oxygen vacancy behavior. The (1 1 0) surface is preferred energetically, being in good agreement with the experiential results. It is uncovered that the weak chemical bond broken dominates the decrease of the surface energy, together with the contribution from the polyhedral distortion. Furthermore, the [O3Si–O–SiO3] site is found to be the preferred site for oxygen vacancies on (1 1 0) surface. The formation energies of oxygen vacancies on the (1 1 0) surfaces are lower than those in the bulk, suggesting their segregation on the surfaces. These findings provide essential insights into the surface excitation and oxygen vacancy behaviors of RE2Si2O7, which could shield light on the experimental improvement of the thermal, mechanical, and corrosion properties for RE2Si2O7‐based environmental barrier coating materials. [ABSTRACT FROM AUTHOR]

In this work, we employ a phase field dislocation dynamics technique to simulate dislocation motion in body centered cubic refractory metals with diffusing interstitials. Two distinct systems are treated, Nb with O interstitials and W with H interstitials, to consider both relatively small and large atomic size interstitials. Simulations without and with driving stress are designed to investigate the role of interstitial type and mobility on the glide of edge- and screw-character dislocations. The simulations reveal the various short- and long-range dislocation-interstitial interactions that can take place and their dependency on interstitial type, site occupation, stress state, and mobility of the interstitials relative to dislocations. We show that while interstitial O increases the breakaway stress for both screw and edge dislocations in Nb, interstitial H in low H concentrations makes screw dislocations easier and the edge dislocations harder to move. The simulations find that screw dislocation glide is enhanced by the presence of interstitials in both systems. Edge dislocation glide is enhanced in W–H and inhibited in Nb–O. [ABSTRACT FROM AUTHOR]

[Display omitted] The treatment of wastewater containing hypophosphite [P(I)] and phosphite [P(III)] is challenged by limitations of traditional Fenton oxidation such as low efficiency, secondary pollution and high costs. This study introduced a facile solvent-thermal method to synthesize Cu-Co 3 O 4 nanoparticles uniformly loaded on graphene (Cu-Co 3 O 4 /U-rGO) through the reduction and coordination effects of urushiol (U). As prepared Cu-Co 3 O 4 /U-rGO exhibited excellent activity in activating peroxymonosulfate (PMS) for the oxidation of P(I)/P(III) to phosphate [P(V)] (0.229 min−1), along with high stability and reusability (91.5 % after 6 cycles), low metal leaching rate (Co: 0.2 mg/L, Cu: 0.05 mg/L), insensitivity to common anions in water and a wide pH range (3–11). The activation mechanism involved the synergistic effects from both urushiol and graphene, which promoted redox of Cu+/Cu2+ and Co2+/Co3+ and induced abundant oxygen vacancies for PMS activation to produce singlet oxygen. Furthermore, the Cu-Co 3 O 4 /U-rGO/PMS was also excellent in the oxidative removal of organic phosphorus. This study is expected to advance strategies for the treatment of P(I)/P(III)-rich wastewater and provide new insights for the development of low-cost, highly efficient heterogeneous catalysts with abundant oxygen vacancies. [ABSTRACT FROM AUTHOR]

[Display omitted] Biocompatible photocatalytic water-splitting systems are promising for tissue self-oxygenation. Herein, a structure–function dual biomimetic fingerprint-like silver phosphate/polydopamine/graphitic carbon nitride (Ag 3 PO 4 /PDA/g-C 3 N 4) heterojunction nanocomposite is proposed for enhanced solar-driven oxygen (O 2) evolution in vivo in situ. Briefly, a porous nitrogen-defected g-C 3 N 4 nanovoile (CN) is synthesized as the base. Dopamine molecules are controllably inserted into the CN interlayer, forming PDA spacers (4.28 nm) through self-polymerization-induced supramolecular-assembly. Ag 3 PO 4 nanoparticles are then in situ deposited to create Ag 3 PO 4 /PDA/CN. The fingerprint-like structure of PDA/CN enlarges the layer spacing, thereby accelerating mass transfer and increasing reaction sites. The PDA spacer roles as excellent light harvester, electronic-ionic conductor, and redox pair through conformational changes, resulting in tailored electronic band structure, optimized carrier behavior, and reduced electrochemical impedance. In physiological conditions, Ag 3 PO 4 /PDA/CN exhibits O 2 evolution rate of 45.35 μmol⋅g−1⋅h−1, 9-fold of bulk g-C 3 N 4. The biocompatibility and in vivo oxygen supply effectiveness for biomedical applications have been verified in animal models. [ABSTRACT FROM AUTHOR]

CO 2 hydrogenation to methanol has become one of the most promising ways for CO 2 utilization, however, the CO 2 conversion rate and methanol selectivity of this reaction still need to be improved for industrial application. Here we investigated the structure-activity relationship for CO 2 conversion to methanol of In 2 O 3 -based catalysts by modulating morphology and decorating Au. Three different Au/In 2 O 3 catalysts were prepared, their activity follow the sequence of Au/In 2 O 3 -nanosphere (Au/In 2 O 3 -NS) > Au/In 2 O 3 -nanoplate (Au/In 2 O 3 -NP) > Au/In 2 O 3 -hollow microsphere (Au/In 2 O 3 -HM). Au/In 2 O 3 -NS exhibited the best performance with good CO 2 conversion of 12.7%, high methanol selectivity of 59.8%, and large space time yield of 0.32 g CH 3 OH /(hr·g cat) at 300°C. The high performance of Au/In 2 O 3 -NS was considered as the presence of Au. It contributes to the creation of more surface oxygen vacancies, which further promoted the CO 2 adsorption and facilitated CO 2 activation to form the formate intermediates towards methanol. This work clearly suggests that the activity of In 2 O 3 catalyst can be effective enhanced by structure engineering and Au decorating. [ABSTRACT FROM AUTHOR]

• Constructing extrinsic oxygen vacancies on the surface of photocatalyst were proposed. • BiOCl quantum dots were used as the source of extrinsic oxygen vacancies. • Extrinsic oxygen vacancies can act as "CO 2 and photo-generated electrons reservoirs. • Extrinsic oxygen vacancies improved photocatalytic CO 2 reduction activity of TiO 2. Constructing own oxygen vacancies in the photocatalysts is a very promising method to improve their photocatalytic CO 2 reduction activity. However, some catalysts have excellent stabilities, making it difficult for them to construct their own oxygen vacancies. To simplify the above difficulty of stable photocatalysts, constructing extrinsic oxygen vacancies on their surface as a novel idea is proposed. Here, a stable TiO 2 nanosheet is chosen as a research object, we uniformly deposited BiOCl quantum dots on their surface via a simple adsorption-deposition method. It is found that BiOCl quantum dots are able to simultaneously self-transform into defective BiOCl with many oxygen vacancies when the photocatalyst is performed photocatalytic CO 2 reduction. These extrinsic oxygen vacancies can act as "CO 2 and photo-generated electrons reservoirs" to improve CO 2 capture and accelerate the separation of photogenerated electrons and holes. For the above reasons, the modified TiO 2 showed obvious enhancement of photocatalytic CO 2 reduction compared to pristine TiO 2 and BiOCl. This work may open a new avenue to broaden the use of oxygen vacancies in the process of photocatalytic CO 2 reduction. [Display omitted] [ABSTRACT FROM AUTHOR]

Recent progresses in intravital imaging have enabled highly-resolved measurements of periarteriolar oxygen gradients (POGs) within the brain parenchyma. POGs are increasingly used as proxies to estimate the local baseline oxygen consumption, which is a hallmark of cell activity. However, the oxygen profile around a given arteriole arises from an interplay between oxygen consumption and delivery, not only by this arteriole but also by distant capillaries. Integrating such interactions across scales while accounting for the complex architecture of the microvascular network remains a challenge from a modelling perspective. This limits our ability to interpret the experimental oxygen maps and constitutes a key bottleneck toward the inverse determination of metabolic rates of oxygen. We revisit the problem of parenchymal oxygen transport and metabolism and introduce a simple, conservative, accurate and scalable direct numerical method going beyond canonical Krogh-type models and their associated geometrical simplifications. We focus on a two-dimensional formulation, and introduce the concepts needed to combine an operator-splitting and a Green's function approach. Oxygen concentration is decomposed into a slowly-varying contribution, discretized by Finite Volumes over a coarse cartesian grid, and a rapidly-varying contribution, approximated analytically in grid-cells surrounding each vessel. Starting with simple test cases, we thoroughly analyze the resulting errors by comparison with highly-resolved simulations of the original transport problem, showing considerable improvement of the computational-cost/accuracy balance compared to previous work. We then demonstrate the model ability to flexibly generate synthetic data reproducing the spatial dynamics of oxygen in the brain parenchyma, with sub-grid resolution. Based on these synthetic data, we show that capillaries distant from the arteriole cannot be overlooked when interpreting POGs, thus reconciling recent measurements of POGs across cortical layers with the fundamental idea that variations of vascular density within the depth of the cortex may reveal underlying differences in neuronal organization and metabolic load. Author summary: The cerebral microvascular network is the logistics system that provides energy to brain cells at the right time and place. Blood flow and oxygen can now be observed dynamically in living rodents, which transformed our knowledge of the system and its role in ageing and disease. However, oxygen concentration at a given location is the result of a subtle balance between local cellular consumption, supply by neighboring vessels and their interconnections to distant ones. Thus, measurements are difficult to interpret without integrating this multi-scale component, which requires advanced computational models. This hinders our ability to bridge the gap between experiments in rodents and clinical applications in humans. In this work, we focus on oxygen transport between vessels, leveraging recent advances in multi-scale modelling and their mathematical foundations. By this way, we formulate for the first time a simple, conservative, accurate and scalable computational model for cerebral oxygen across scales, that is able to integrate the spatially heterogenous distribution of vessels. We illustrate how this model, combined to imaging, will pave the way towards better estimates of oxygen consumption, a hallmark of neural activity that cannot be directly measured. [ABSTRACT FROM AUTHOR]

Herein, we synthesised a series of nonstoichiometric Nd−Ce−O composite oxides with a fluorite or rare‐earth C‐type phase structure using the glycine combustion method for the oxidative coupling of methane (OCM) reaction. As the amount of Nd3+ increases, the oxygen vacancies in this series of composite oxides gradually increase, leading to an amount increasing in the C2‐selective oxygen species O2− generated by the oxygen vacancies. In addition, with the increase in Nd3+, the number of moderate basic sites on the catalyst surface also improves, another significant factor affecting the OCM reaction performance of the composite oxides. Nd0.9Ce0.1O1.55 possesses optimal low‐temperature OCM reaction performance, achieving 8.0 % C2 yield at 450 °C and 14.1 % C2 yield at 700 °C. This can be attributed to the nonstoichiometric rare‐earth C‐type crystalline phase structure of Nd0.9Ce0.1O1.55, which exhibits the highest abundance of oxygen vacancies, selective oxygen species O2−, and moderate basic sites. [ABSTRACT FROM AUTHOR]

In order to increase the concentration of Mg in single crystal and epitaxial Ga2O3 solely via diffusion doping technique, different variations of diffusion methods are explored. First, a one-step infinite-source diffusion is compared with a two-step finite-source diffusion. The two-step diffusion is shown to be effective in increasing the Mg concentration in Ga2O3 by nearly 10 times. Furthermore, it was observed that the ambient gas used in the second step diffusion plays a critical role in Mg diffusion. The SIMS result is compared between a sample with second step diffusion in oxygen and another sample in a nitrogen ambient while keeping all other conditions identical. The presence of oxygen gas in the second step annealing is shown to be essential to the increase in Mg concentration and the disassociation of the Mg-H complex. Finally, the current–voltage blocking characteristics of the formed Mg-diffused current blocking layers are measured and are observed to have significantly increased from ∼500 V to more than 1 kV with the achieved Mg diffusion concentration profiles. The two-step oxygen-assisted Mg diffusion doping technique has shown to be a simple yet useful doping tool that paves the way for the realization of various high-power Ga2O3 electron devices. [ABSTRACT FROM AUTHOR]

This study explores the transition in combustion technologies from dry micro-mix hydrogen-air to wet micro-mix hydrogen-oxygen configurations. The investigation involves a comprehensive analysis of the combustion processes currently being considered for converting methane gas turbines to methane-hydrogen mixtures and hydrogen, including wet premixed, dry low emission, sequential combustion, and micro-mix, examining key parameters such as efficiency, emissions, and overall performance. Then, the work considers the shift from utilizing air as an oxidizer to oxygen. Wet micro-mix hydrogen-oxygen combustion is then discussed for its impact on combustion dynamics and the potential for achieving zero emissions, cancelling NOx emissions in addition to CO 2 emissions. The findings contribute valuable insights into the feasibility and advantages of transitioning from conventional hydrogen-air combustion to innovative wet hydrogen-oxygen combustion, paving the way for more sustainable and environmentally friendly combustion technologies. Scheme of a hydrogen energy storage system comprising one electrolyser, two tanks for the hydrogen and the oxygen, and an O 2 /H 2 /H 2 O gas turbine power system. The system could be able to receive non-dispatchable electricity and release dispatchable electricity working as a battery but without any limitation on the amount of energy storable, or the time of the storage. [Display omitted] [ABSTRACT FROM AUTHOR]

Within this work, reticulated monolithic foams and granules made from CaMnO3 − δ and strontium substituted variations are demonstrated to significantly improve the performance of a water splitting redox oxide when employed as a thermochemical oxygen pumping material. Two different process procedures are tested and foams made from Ca0.9Sr0.1MnO3 − δ with a strontium content of 10% outperform all other specimens in both process configurations. Additionally, the performance of Ca1 − xSrxMnO3 − δ with varying strontium content as a thermochemical oxygen pumping material is studied by means of a newly developed theoretical process model. While the model does not precisely predict the excellent experimental performance of strontium‐substitute compositions, it provides valuable insights into the impact of geometry and structure on the specimen's performance in thermochemical oxygen‐pumping processes. This work demonstrates the practical application of monolithic 3D structures made entirely from perovskite material in thermochemical oxygen pumping processes and provides a process model that can serve as basis for material screening and process optimization in future work. [ABSTRACT FROM AUTHOR]

Sterols and the reductant nicotinamide adenine dinucleotide phosphate (NADPH), essential for eukaryotic life, arose because of, and as an adaptation to, rising levels of molecular oxygen (O2). Hence, the NADPH and O2‐intensive process of sterol biosynthesis is inextricably linked to redox status. In mammals, cholesterol biosynthesis is exquisitely regulated post‐translationally by multiple E3 ubiquitin ligases, with membrane associated Really Interesting New Gene (RING) C3HC4 finger 6 (MARCHF6) degrading at least six enzymes in the pathway. Intriguingly, all these MARCHF6‐dependent enzymes require NADPH. Moreover, MARCHF6 is activated by NADPH, although what this means for control of cholesterol synthesis is unclear. Indeed, this presents a paradox for how NADPH regulates this vital pathway, since NADPH is a cofactor in cholesterol biosynthesis and yet, low levels of NADPH should spare cholesterol biosynthesis enzymes targeted by MARCHF6 by reducing its activity. We speculate MARCHF6 helps mammalian cells adapt to oxidative stress (signified by low NADPH levels) by reducing degradation of cholesterogenic enzymes, thereby maintaining synthesis of protective cholesterol. [ABSTRACT FROM AUTHOR]

Simple Summary: In order to grow, tumors need nutrients and oxygen, which are supplied by new blood vessels that are often abnormal and leaky. The development of these blood vessels is driven by proteins called growth factors, which bind to receptor proteins on other cells. We show for the first time that an antibody against a vascular growth factor called VEGF-B, when used to treat mice with tumors, reduces the amount of abnormal tumor blood vessels, and inhibits tumor growth, as well as improving the response to chemotherapy. These results suggest that targeting VEGF-B could be a potential approach for anti-cancer therapy, particularly in combination with chemotherapy. The vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key regulators of blood vessel formation, including in tumors, where their deregulated function can promote the production of aberrant, leaky blood vessels, supporting tumor development. Here we investigated the VEGFR1 ligand VEGF-B, which we demonstrate to be expressed in tumor cells and in tumor stroma and vasculature across a range of tumor types. We examined the anti-VEGF-B-specific monoclonal antibody 2H10 in preclinical xenograft models of breast and colorectal cancer, in comparison with the anti-VEGF-A antibody bevacizumab. Similar to bevacizumab, 2H10 therapy was associated with changes in tumor blood vessels and intra-tumoral diffusion consistent with normalization of the tumor vasculature. Accordingly, treatment resulted in partial inhibition of tumor growth, and significantly improved the response to chemotherapy. Our studies indicate the importance of VEGF-B in tumor growth, and the potential of specific anti-VEGF-B treatment to inhibit tumor development, alone or in combination with established chemotherapies. [ABSTRACT FROM AUTHOR]

Dissolved Oxygen (DO) in water enables marine life. Measuring the prevalence of DO in a body of water is an important part of sustainability efforts because low oxygen levels are a primary indicator of contamination and distress in bodies of water. Therefore, aquariums and aquaculture of all types are in need of near real-time dissolved oxygen monitoring and spend a lot of money on purchasing and maintaining DO meters that are either expensive, inefficient, or manually operated—in which case they also need to ensure that manual readings are taken frequently which is time consuming. Hence a cost-effective and sustainable automated Internet of Things (IoT) system for this task is necessary and long overdue. DOxy, is such an IoT system under research and development at Santa Clara University's Ethical, Pragmatic, and Intelligent Computing (EPIC) Laboratory which utilizes cost-effective, accessible, and sustainable Sensing Units (SUs) for measuring the dissolved oxygen levels present in bodies of water which send their readings to a web based cloud infrastructure for storage, analysis, and visualization. DOxy's SUs are equipped with a High-sensitivity Pulse Oximeter meant for measuring dissolved oxygen levels in human blood, not water. Hence a number of parallel readings of water samples were gathered by both the High-sensitivity Pulse Oximeter and a standard dissolved oxygen meter. Then, two approaches for relating the readings were investigated. In the first, various machine learning models were trained and tested to produce a dynamic mapping of sensor readings to actual DO values. In the second, curve-fitting models were used to produce a successful conversion formula usable in the DOxy SUs offline. Both proved successful in producing accurate results. [ABSTRACT FROM AUTHOR]