Oxygen Transport Research Articles

Deep‐GB: A novel deep learning model for globular protein prediction using CNN‐BiLSTM architecture and enhanced PSSM with trisection strategy

AbstractGlobular proteins (GPs) play vital roles in a wide range of biological processes, encompassing enzymatic catalysis and immune responses. Enzymes, among these globular proteins, facilitate biochemical reactions, while others, such as haemoglobin, contribute to essential physiological functions such as oxygen transport. Given the importance of these considerations, accurately identifying Globular proteins is essential. To address the need for precise GP identification, this research introduces an innovative approach that employs a hybrid‐based deep learning model called Deep‐GP. We generated two datasets based on primary sequences and developed a novel feature descriptor called, Consensus Sequence‐based Trisection‐Position Specific Scoring Matrix (CST‐PSSM). The model training phase involved the application of deep learning techniques, including the bidirectional long short‐term memory network (BiLSTM), gated recurrent unit (GRU), and convolutional neural network (CNN). The BiLSTM and CNN were hybridised for ensemble learning. The CST‐PSSM‐based ensemble model achieved the most accurate predictive outcomes, outperforming other competitive predictors across both training and testing datasets. This demonstrates the potential of harnessing deep learning for precise GB prediction as a robust tool to expedite research, streamline drug discovery, and unveil novel therapeutic targets.

Research Progress of Spectral Imaging Techniques in Plant Phenotype Studies

Spectral imaging technique has been widely applied in plant phenotype analysis to improve plant trait selection and genetic advantages. The latest developments and applications of various optical imaging techniques in plant phenotypes were reviewed, and their advantages and applicability were compared. X-ray computed tomography (X-ray CT) and light detection and ranging (LiDAR) are more suitable for the three-dimensional reconstruction of plant surfaces, tissues, and organs. Chlorophyll fluorescence imaging (ChlF) and thermal imaging (TI) can be used to measure the physiological phenotype characteristics of plants. Specific symptoms caused by nutrient deficiency can be detected by hyperspectral and multispectral imaging, LiDAR, and ChlF. Future plant phenotype research based on spectral imaging can be more closely integrated with plant physiological processes. It can more effectively support the research in related disciplines, such as metabolomics and genomics, and focus on micro-scale activities, such as oxygen transport and intercellular chlorophyll transmission.

Computer model coupling hemodynamics and oxygen transport in the coronary capillary network: Pulsatile vs. non-pulsatile analysis

Background and Objective:Oxygen transport in the heart is crucial, and its impairment can lead to pathological conditions such as hypoxia, ischemia, and heart failure. However, investigating oxygen transport in the heart using in vivo measurements is difficult due to the small size of the coronary capillaries and their deep embedding within the heart wall. Methods:In this study, we developed a novel computational modeling framework that integrates a 0-D hemodynamic model with a 1-D mass transport model to simulate oxygen transport in/across the coronary capillary network. Results:The model predictions agree with analytical solutions and experimental measurements. The framework is used to simulate the effects of pulsatile vs. non-pulsatile behavior of the capillary hemodynamics on oxygen-related metrics such as the myocardial oxygen consumption (MVO2) and oxygen extraction ratio (OER). Compared to simulations that consider (physiological) pulsatile behaviors of the capillary hemodynamics, the OER is underestimated by less than 9% and the MVO2 is overestimated by less than 5% when the pulsatile behaviors are ignored in the simulations. Statistical analyses show that model predictions of oxygen-related quantities and spatial distribution of oxygen without consideration of the pulsatile behaviors do not significantly differ from those that considered such behaviors (p-values >0.05). Conclusions:This finding provides the basis for reducing the model complexity by ignoring the pulsatility of coronary capillary hemodynamics in the computational framework without a substantial loss of accuracy when predicting oxygen-related metrics.

Genome sequencing and transcriptome analysis provide an insight into the hypoxia resistance of Channa asiatica

Channa asiatica is an economically valuable fish species and excellent model for studying hypoxic tolerance. However, the underlying genetic and molecular mechanisms are poorly understood. In this study, we assembled a high-quality C. asiatica genome (23 chromosomes, totaling 722 Mb) using a combination of Illumina short-read, PacBio long-read, and Hi-C sequencing. Repetitive elements accounted for 28.39%of the C. asiatica genome, and 23,949 protein-coding genes were predicted, with 96.63 % of these functionally annotated. Moreover, a comparative genomic analysis of 12 fish genomes showed that gene families associated with oxygen binding and transport were expanded in C. asiatica. In addition, transcriptome analysis revealed that multiple oxidative stress pathways were activated when C. asiatica was exposed to air. In conclusion, this study provided high-quality genome assembly and transcriptome data, both serving as critical resources for researching the genetic basis of hypoxic tolerance in C. asiatica.

Folic Acid Before and During Pregnancy

Folate is a key nutrient required to maintain optimal health, especially when planning a family or during pregnancy. The functionality of folate centres on the production of healthy red blood cells, important for the transportation of oxygen around the body. It supports development of the foetal nervous system specifically neural tube growth, with evidence showing that taking folic acid supplements before and during pregnancy reduces the chance of the baby developing spina bifida and other conditions affecting the spine and neural tube.1 Folate is essential for DNA replication, and may protect against miscarriage, premature birth and low birth weight, with beneficial effects in the prevention of structural anomalies, congenital heart disease and oral clefts.2

Breath inspired multifunctional low-cost inorganic colloidal electrolyte for stable zinc metal anode

The practical application of aqueous zinc-ion batteries (AZIBs) is primarily constrained by issues such as corrosion, zinc dendrite formation, and the hydrogen evolution reaction occurring at the zinc metal anode. To overcome these challenges, strategies for optimizing the electrolyte are crucial for enhancing the stability of the zinc anode. Inspired by the role of hemoglobin in blood cells, which facilitates oxygen transport during human respiration, an innovative inorganic colloidal electrolyte has been developed: calcium silicate-ZnSO4 (denoted as CS-ZSO). This electrolyte operates in weak acidic environment and releases calcium ions, which participate in homotopic substitution with zinc ions, while the solvation environment of hydrated zinc ions in the electrolyte is regulated. The reduced energy barrier for the transfer of zinc ions and the energy barrier for the desolvation of hydrated ions imply faster ion transfer kinetics and accelerated desolvation processes, thus favoring the mass transfer process. Furthermore, the silicate colloidal particles act as lubricants, improving the transfer of zinc ions. Together, these factors contribute to the more uniform concentration of zinc ions at the electrode/electrolyte interface, effectively inhibiting zinc dendrite formation and reducing by-product accumulation. The Zn//CS-ZSO//Zn symmetric cell demonstrates stable operation for over 5000 h at 1 mA cm−2, representing 29-fold improvement compared to the Zn//ZSO//Zn symmetric cell, which lasts only 170 h. Additionally, the Zn//CS-ZSO//Cu asymmetric cell shows stable average Coulombic efficiency (CE) exceeding 99.6% over 2400 cycles, significantly surpassing the performance of the ZSO electrolyte. This modification strategy for electrolytes not only addresses key limitations associated with zinc anodes but also provides valuable insights into stabilizing anodes for the advancement of high-performance aqueous zinc-ion energy storage systems.

Recycling of hydrogen tolerant La0.6Ca0.4Co0.2Fe0.8O3–d oxygen transport membranes with integrated life cycle assessment for plasma-assisted CO2-conversion

In this study, a recycling approach was adapted for the hydrogen tolerant La0.6Ca0.4Co0.2Fe0.8O3–d (LCCF_6428) oxygen transport membranes that have great potential in plasma-assisted CO2 conversion techniques for producing industrial fuels such as methanol. The major focus was the incorporation of sustainability measures such as integrating life cycle assessment (LCA) into the materials development at an early stage to study and compare the environmental feasibility of the recycled membrane with the primary membrane. The aim was also to ensure reduced resource depletion of critical raw materials such as cobalt and lanthanum by means of recycling. It consisted of microwave-assisted dissolution of the membrane followed by ultrasonic spray synthesis. The recycled membrane exhibited at least 83 % of the oxygen permeability of the primary membrane and maintained hydrogen tolerance up to 600 °C for 25 h which is a remarkable result for LCCF_6428 in terms of potentially enhancing its life span. As per the LCA, recycling did result in lower resource depletion. However, the recycled LCCF had a higher overall environmental impact compared to the primary LCCF, mainly due to increased electricity consumption during recycling. These results accentuate the need for a transition towards more efficient processes accompanied by cleaner and renewable sources of energy and critically indicate integration of LCA into materials development to establish the sustainability profile of materials.

Patient-specific prostate tumour growth simulation: a first step towards the digital twin

Prostate cancer (PCa) is a major world-wide health concern. Current diagnostic methods involve Prostate-Specific Antigen (PSA) blood tests, biopsies, and Magnetic Resonance Imaging (MRI) to assess cancer aggressiveness and guide treatment decisions. MRI aligns with in silico medicine, as patient-specific image biomarkers can be obtained, contributing towards the development of digital twins for clinical practice. This work presents a novel framework to create a personalized PCa model by integrating clinical MRI data, such as the prostate and tumour geometry, the initial distribution of cells and the vasculature, so a full representation of the whole prostate is obtained. On top of the personalized model construction, our approach simulates and predicts temporal tumour growth in the prostate through the Finite Element Method, coupling the dynamics of tumour growth and the transport of oxygen, and incorporating cellular processes such as proliferation, differentiation, and apoptosis. In addition, our approach includes the simulation of the PSA dynamics, which allows to evaluate tumour growth through the PSA patient’s levels. To obtain the model parameters, a multi-objective optimization process is performed to adjust the best parameters for two patients simultaneously. This framework is validated by means of data from four patients with several MRI follow-ups. The diagnosis MRI allows the model creation and initialization, while subsequent MRI-based data provide additional information to validate computational predictions. The model predicts prostate and tumour volumes growth, along with serum PSA levels. This work represents a preliminary step towards the creation of digital twins for PCa patients, providing personalized insights into tumour growth.

A comparative study on the Lattice Boltzmann Method and the VoF-Continuum method for oxygen transport in the anodic porous transport layer of an electrolyzer

The optimization of Polymer Electrolyte Membrane (PEM) electrolyzers necessitates an intimate knowledge of the oxygen flows within the anodic porous transport layers (PTLs) to determine any possible reduction in performance. In this field, as experimental studies are cumbersome and expensive, numerical modeling has arisen as a viable alternative for studying the oxygen transport within the Anodic PTLs of a PEM electrolyzer. Amongst the various numerical modeling techniques, the Lattice Boltzmann Method (LBM) is gaining prominence for its effectiveness in analyzing fluid transport within porous media due to its mesoscopic nature and ease of implementation. This study utilizes the Shan-Chen LBM methodology to model the flow of oxygen within the Anodic PTL of a PEM electrolyzer and compares it against the Volume-of-Fluid-based Continuum Model. The results show that LBM can not only replicate the experimental studies accurately, but can also maintain its high accuracy at progressively shrinking length scales of PTLs, even at length scales where the VoF-based Continuum Model would run into accuracy issues. The high accuracy of the LBM model, combined with the simplicity of the LB algorithm makes LBM a powerful technique for simulating the microfluidic flows such as the flow of oxygen within the Anodic PTL of a PEM electrolyzer.

Performance constraints of high temperature polymer electrolyte membrane fuel cells by varying the Pt/C ratio of the catalyst

Electrodes prepared from catalysts with Pt weight percentages on the carbon support (Pt/C nanoparticles) ranging from 10 up to 60 wt% are used as cathodes of membrane electrode assemblies (MEAs) and tested in high temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). For each Pt/C percentage in the catalyst, the cathode Pt-loading (which become proportional to the thickness of the electrode formed by the catalyst nanoparticles) is stepwise scanned from low to high loadings. Results show that when the Pt load increases, the MEA performance (measured by its power density at 0.6 V) rises initially (due to the increase in the number of active sites in the cathode) up to a maximum value limited by the mass transport of oxygen, associated to an optimum Pt-loading (different for each Pt/C ratio). Noteworthy, the peak performance is significantly different depending on the catalyst used (60 > 40 >> 20 > 10 wt% Pt/C), a fact that restricts the catalyst choice according to the performance required by the application. Furthermore, higher amounts of Pt in the cathode lead to a large catalyst waste as the FC performance even decreases as the cathode thickness increases.

Primary inflammatory disease in heart failure with preserved ejection fraction

Abstract Background Inflammation plays a fundamental role in the pathogenesis of heart failure (HF) with preserved ejection fraction (HFpEF). In most patients, inflammation develops secondary to cardiometabolic comorbidities, but in some, HFpEF develops in the setting of underlying systemic inflammatory diseases represented by rheumatoid arthritis. Purpose This study aimed to investigate the prevalence, pathophysiology, and outcome of patients with HFpEF and primary inflammatory diseases. Methods Consecutive patients undergoing hemodynamic exercise testing with concurrent expiratory gas analysis to evaluate dyspnea of unknown cause were identified. HFpEF was defined as left ventricular ejection fraction ≥50% and pulmonary capillary wedge pressure ≥15 mmHg (rest) or ≥25 mmHg (exercise). Patients with HFpEF were divided into groups with and without primary inflammatory diseases. Patients without inflammatory disease were divided into tertiles according to the value of C-reactive protein (CRP). Results Of 982 consecutively evaluated patients with HFpEF diagnosed (577 female, mean age 68 years), 79 (8%) had primary inflammatory disease. In multivariable logistic regression, female sex (OR 1.88; 95% CI 1.01-3.52), higher resting heart rate (OR 1.18; 95% CI 1.08-1.30), lower hemoglobin level (OR 0.84; 95% CI 0.70-0.99), absence of history of atrial fibrillation (OR 0.45; 95% CI 0.24-0.86) and absence of epicardial coronary artery disease (OR 0.45; 95% CI 0.22-0.93) were independently associated with inflammatory disease. Hemodynamics at rest and exercise did not differ between the groups, but peripheral oxygen extraction was lower in those with inflammatory disease, reflected by lower arterial-venous oxygen content difference (Ca-vO2) at rest (4.2±0.7 mL/dL vs 4.6±1.0 mL/dL, P<.001) and during exercise (9.3±2.2 mL/dL vs 10.4±2.2 mL/dL, P<.001) (Figure 1A), suggesting a greater peripheral deficit, and ventilatory efficiency (VE/VCO2 slope) was also more impaired (38.0±7.9 vs 36.2±7.3, P=.035). The HFpEF patients without inflammatory disease falling in the highest tertile of CRP) displayed lower Ca-vO2 during exercise, more closely resembling peripheral deficits observed in those with inflammatory disease (Figure 1B). During a median follow-up of 3.0 years, the composite outcome of all-cause deaths and HF hospitalization occurred in 127 patients (14%). Patients with HFpEF and inflammatory disease showed a higher incidence of composite outcome than those without (log-rank P=.030; Figure 2). Patients with inflammatory disease had higher risk of composite outcome compared to those without in adjusted analyses (HR 1.93; 95% CI 1.15-3.23), which was primarily attributable to higher risk of HF hospitalization (HR 2.85; 95% CI 1.08-7.52). Conclusion Patients with HFpEF and primary inflammatory disease have similar hemodynamic derangements but greater peripheral deficits in oxygen transport and higher risk for adverse outcome compared to those without.

Influence of Inner Crucible Radius Variation on the Thermal Field and Oxygen Transport in the Melt During the Growth of Silicon by Continuous Czochralski Method

Influence of Inner Crucible Radius Variation on the Thermal Field and Oxygen Transport in the Melt During the Growth of Silicon by Continuous Czochralski Method

Development of Grooves in Gas Diffusion Layers for PEM Fuel Cells Considering Mechanisms of Oxygen Transport and Water Drainage

Development of Grooves in Gas Diffusion Layers for PEM Fuel Cells Considering Mechanisms of Oxygen Transport and Water Drainage

Overcoming the Limitation of Ionomers on Mass Transport and Pt Activity to Achieve High-Performing Membrane Electrode Assembly.

The membrane electrode assembly (MEA) is one of the critical components in proton exchange membrane fuel cells (PEMFCs). However, the conventional MEA cathode with a covered-type catalyst/ionomer interfacial structure severely limits oxygen transport efficiency and Pt activity, hardly achieving the theoretical performance upper bound of PEMFCs. Here, we design a noncovered catalyst/ionomer interfacial structure with low proton transport resistance and high oxygen transport efficiency in the cathode catalyst layer (CL). This noncovered interfacial structure employs the ionomer cross-linked carbon particles as long-range and fast proton transport channels and prevents the ionomer from directly covering the Pt/C catalyst surface in the CL, freeing the oxygen diffusion process from passing through the dense ionomer covering layer to the Pt surface. Moreover, the structure improves oxygen transport within the pores of the CL and achieves more than 20% lower pressure-independent oxygen transport resistance compared to the covered-type structure. Fuel-cell diagnostics demonstrate that the noncovered catalyst/ionomer interfacial structure provides exceptional fuel-cell performance across the kinetic and mass transport-limited regions, with 77% and 67% higher peak power density than the covered-type interfacial structure under 0 kPagauge of oxygen and air conditions, respectively. This alternative interfacial structure provides a new direction for optimizing the electrode structure and improving mass-transport paths of MEA.

Haemoglobin Gene Repertoire in Teleost and Cichlid Fishes Shaped by Gene Duplications and Genome Rearrangements.

Haemoglobin is a key molecule for oxygen transport in vertebrates. It exhibits remarkable gene diversity in teleost fishes, reflecting adaptation to various aquatic environments. In this study, we present the dynamic evolution of haemoglobin subunit genes based on a comparison of high-quality genome assemblies of 24 vertebrate species, including 17 teleosts (of which six are cichlids). Our findings indicate that teleost genomes contain a range of haemoglobin genes, from as few as five in fugu to as many as 43 in salmon, with the latter being the largest repertoire found in vertebrates. We find evidence that the teleost ancestor had at least four Hbα and three or four Hbβ subunit genes, and that the current gene diversity emerged during teleost radiation, driven primarily by (tandem) gene duplications, genome compaction, and rearrangement dynamics. We provide insights into the genomic organisation of haemoglobin clusters in different teleost species. We further show that the evolution of paralogous rhbdf1 genes flanking both teleost clusters (LA and MN) supports the hypothesis for the origin of the LA cluster by rearrangement within teleosts, rather than by the teleost specific whole-genome duplication. We specifically focus on cichlid fishes, where adaptation to low oxygen environment plays role in species diversification. Our analysis of six cichlid genomes, including Pungu maclareni from the Barombi Mbo crater lake, for which we sequenced a representative genome, reveals 18-32 copies of the Hb genes, and elevated rates of non-synonymous substitutions compared to other teleosts. Overall, this work facilitates a deeper understanding of how haemoglobin genes contribute to the adaptive potential of teleosts.

Higher oxygen content and transport characterize high-altitude ethnic Tibetan women with the highest lifetime reproductive success

We chose the "natural laboratory" provided by high-altitude native ethnic Tibetan women who had completed childbearing to examine the hypothesis that multiple oxygen delivery traits were associated with lifetime reproductive success and had genomic associations. Four hundred seventeen (417) women aged 46 to 86 y residing at ≥3,500 m in Upper Mustang, Nepal, provided information on reproductive histories, sociocultural factors, physiological measurements, and DNA samples for this observational cohort study. Simultaneously assessing multiple traits identified combinations associated with lifetime reproductive success measured as the number of livebirths. Women with the most livebirths had distinctive hematological and cardiovascular traits. A hemoglobin concentration near the sample mode and a high percent of oxygen saturation of hemoglobin raised arterial oxygen concentration without risking elevated blood viscosity. We propose ongoing stabilizing selection on hemoglobin concentration because extreme values predicted fewer livebirths and directional selection favoring higher oxygen saturation because higher values had more predicted livebirths. EPAS1, an oxygen homeostasis locus with strong signals of positive natural selection and a high frequency of variants occurring only among populations indigenous to the Tibetan Plateau, associated with hemoglobin concentration. High blood flow into the lungs, wide left ventricles, and low hypoxic heart rate responses aided effective convective oxygen transport to tissues. Women with physiologies closer to unstressed, low altitude values had the highest lifetime reproductive success. This example of ethnic Tibetan women residing at high altitudes in Nepal links reproductive fitness with trait combinations increasing oxygen delivery under severe hypoxic stress and demonstrates ongoing natural selection.

Assessing the chronic toxicity of climbazole to Daphnia magna: Physiological, biochemical, molecular, and reproductive perspectives

The widespread use of climbazole (CBZ) has led to its increased presence in aquatic environments, potentially threatening freshwater ecosystems. However, evidence regarding the harmful effects of CBZ on aquatic organisms remains limited. In this study, Daphnia magna was exposed to CBZ at concentrations of 0, 0.2, 20, and 200 μg/L for 21 days to evaluate its chronic toxicity through assessment of life-history traits, physiological parameters, biochemical analyses, and gene expression. The results indicated that CBZ exposure delayed the days to the first brood, reduced the frequency of molting per adult, decreased the offspring number at first brood, diminished the body length, and decreased both the total number of broods per female and the total number of offspring per female. Additionally, CBZ inhibited the swimming speed, filtration rate, and ingestion rate. Moreover, CBZ altered the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), while increasing malondialdehyde (MDA) levels. Gene expression analysis revealed varied responses in mRNA levels related to metabolic detoxification (cyp360a8, gst, and p-gp), digestive enzymes (α-amylase, α-esterase, and trypsin), energy (ak), oxygen transport (dhb), and reproduction (nvd, cyp314, ecr, vtg, and jhe) following CBZ exposure. These results indicate that the presence of CBZ in aquatic environments can induce toxicity by altering energy acquisition, supply, and metabolism; impairing metabolic detoxification pathways; eliciting oxidative stress; and causing reproductive toxicity in D. magna.

STATE OF HAEMODYNAMICS AND OXYGEN BUDGET IN THE PERIOPERATIVE PERIOD IN PATIENTS WITH OSTEOARTHRITIS AND CONCOMITANT CARDIAC PATHOLOGY DURING TOTAL HIP ARTHROPLASTY SURGERY DEPENDING ON THE TYPE OF SURGICAL ACCESS

Summary. Aim. To compare the hemodynamic status and oxygen budget in patients with osteoarthritis and comorbid cardiac pathology during total hip arthroplasty, based on the type of surgical approach used. Materials and Methods. The study analyzed the treatment outcomes of 90 patients with stage 3-4 osteoarthritis of the hip who underwent total cemented hip arthroplasty. All patients were divided into two groups according to the surgical approach (traditional posterior or modified posterior). The study was conducted at the following stages: before surgery, immediately after surgery, 24 hours post-surgery, and one week after surgery. The following parameters were recorded: hemodynamic parameters (heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure, and central venous pressure) and oxygen budget parameters (hemoglobin (Hb), lactate, hematocrit (Ht), oxygen saturation of hemoglobin in arterial and venous blood (SaO2 and SvO2), partial pressure of oxygen in arterial and venous blood (paO2 and pvO2)). Based on these data, the following indices were calculated: left ventricular ejection fraction (LVEF), cardiac index (CI); oxygen content in arterial and venous blood (CaO2 and CvO2), arteriovenous oxygen content difference (C(a-v)O2), oxygen transport (TO2), oxygen consumption (VO2); systemic perfusion pressure (SPP), blood flow power (BFP), oxygen reserve (OR), and circulatory reserve (CR). Results. The use of the modified posterior approach positively influenced hemodynamic parameters. After the surgery and on the 7th day post-surgery, SPP was significantly lower with the modified posterior approach. The CI was also significantly affected by the modified posterior approach. Throughout the study, except for the first stage, CI was significantly higher when using the modified posterior approach. LVEF increased significantly with both approaches, but on the 7th day post-surgery, it was significantly higher in the second group. BFP did not statistically differ between the two groups throughout the study, but its energy efficiency was lower, primarily due to the arteriovenous oxygen content difference (C(a-v)O2). C(a-v)O2 was the same before surgery for both approaches. At subsequent stages of the study, the differences between the groups increased, and on the 7th day, they were the most significant, with C(a-v)O2 being lower after using the modified posterior approach. The energy efficiency of blood flow was assessed by calculating OR and CR. Both indicators were significantly higher during the study, except at the preoperative stage, when using the modified posterior approach. Conclusions. Our study clearly demonstrates the benefits of implementing the modified posterior approach in total hip arthroplasty for patients with osteoarthritis and comorbid cardiac pathology. This approach improves hemodynamic and oxygen budget parameters compared to the traditional approach, which can significantly impact treatment outcomes for patients with cardiac comorbidity and reduce the number of postoperative complications.

Computational Fluid Dynamics Modelling of Hydrogen Production via Water Splitting in Oxygen Membrane Reactors.

The utilization of oxygen transport membranes enables the production of high-purity hydrogen by the thermal decomposition of water below 1000 °C. This process is based on a chemical potential gradient across the membrane, which is usually achieved by introducing a reducing gas. Computational fluid dynamics (CFD) can be used to model reactors based on this concept. In this study, a modelling approach for water splitting is presented in which oxygen transport through the membrane acts as the rate-determining process for the overall reaction. This transport step is implemented in the CFD simulation. Both gas compartments are modelled in the simulations. Hydrogen and methane are used as reducing gases. The model is validated using experimental data from the literature and compared with a simplified perfect mixing modelling approach. Although the main focus of this work is to propose an approach to implement the water splitting in CFD simulations, a simulation study was conducted to exemplify how CFD modelling can be utilized in design optimization. Simplified 2-dimensional and rotational symmetric reactor geometries were compared. This study shows that a parallel overflow of the membrane in an elongated reactor is advantageous, as this reduces the back diffusion of the reaction products, which increases the mean driving force for oxygen transport through the membrane.

Fluorine‐Lodged High‐Valent High‐Entropy Layered Double Hydroxide for Efficient, Long‐Lasting Zinc‐Air Batteries

AbstractEfficient and stable bifunctional oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) catalysts are urgently needed to unlock the full potential of zinc‐air batteries (ZABs). High‐valence oxides (HVOs) and high entropy oxides (HEOs) are suitable candidates for their optimal electronic structures and stability but suffer from demanding synthesis. Here, a low‐cost fluorine‐lodged high‐valent high‐entropy layered double hydroxide (HV‐HE‐LDH) (FeCoNi2F4(OH)4) is conveniently prepared through multi‐ions co‐precipitation, where F− are firmly embedded into the individual hydroxide layers. Spectroscopic detections and theoretical simulations reveal high valent metal cations are obtained in FeCoNi2F4(OH)4, which enlarge the energy band overlap between metal 3d and O 2p, enhancing the electronic conductivity and charge transfer, thus affording high intrinsic OER catalytic activity. More importantly, the strengthened metal‐oxygen (M−O) bonds and stable octahedral geometry (M−O(F)6) in FeCoNi2F4(OH)4 prevent structural reorganization, rendering long‐term catalytic stability. Furthermore, an efficient three‐phase reaction interface with fast oxygen transportation was constructed, significantly improving the ORR activity. ZABs assembled with FeCoNi2F4(OH)4@HCC (hydrophobic carbon cloth) cathodes deliver a top performance with high round‐trip energy efficiency (61.3 % at 10 mA cm−2) and long‐term stability (efficiency remains at 58.8 % after 1050 charge–discharge cycles).