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The aim of this study is to suggest a novel approach for estimating the intramolecular mobility of a charge carrier that migrates within a polymer chain and is involved in a pair reaction with a particle located on the same chain. The approach is based on the effect of an external electric field on the migration rate and, consequently, the kinetics of the reaction. As a first step, this problem is considered a stochastic one-step process with absorbing and reflecting boundaries, and an analytical solution is obtained in the case that the second reactant is immobile. With the use of computer simulations of stochastic migration, the effect of the mobility of both reactants and the influence of the Coulomb interaction between them are considered. It is found that the ratio of the pair reaction rates with and without an external field is relatively little dependent on these factors and that the analytical expressions derived can be applied to estimate the relative mobility of recombining particles with accuracy better than a factor of two in many realistic situations. [ABSTRACT FROM AUTHOR]

Background: Ex vivo machine perfusion (EVMP) has been established to extend viability of donor organs. However, EVMP protocols are inconsistent. We hypothesize that there is a significant relationship between specific parameters during EVMP and perfusion outcomes. Methods: A meta‐analysis of literature was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta‐Analysis (PRISMA) Statement. The search encompassed articles published before July 25, 2023. PubMed, Embase, and CENTRAL databases were screened using search terms "ex‐vivo," "ex‐situ," "machine," and "perfusion." Weight gain, an indicator of organ viability, was chosen to compare outcomes. Extracted variables included perfused organ, warm and cold ischemia time before perfusion, perfusion duration, perfusate flow, pressure, temperature, perfusate composition (presence of cellular or acellular oxygen carrier, colloids, and other supplements) and percent weight change. Data were analyzed using SPSS statistical software. Results: Overall, 44 articles were included. Red blood cell‐based perfusates resulted in significantly lower weight gain compared to acellular perfusates without oxygen carriers (11.3% vs. 27.0%, p < 0.001). Hemoglobin‐based oxygen carriers resulted in significantly lower weight gain compared to acellular perfusates (16.5% vs. 27%, p = 0.006). Normothermic perfusion led to the least weight gain (14.6%), significantly different from hypothermic (24.3%) and subnormothermic (25.0%) conditions (p < 0.001), with no significant difference between hypothermic and subnormothermic groups (24.3% vs. 25.0%, p = 0.952). There was a positive correlation between flow rate and weight gain (ß = 13.1, R = 0.390, p < 0.001). Conclusions: Oxygen carriers, low flow rates, and normothermic perfusate temperature appear to improve outcomes in EVMP. These findings offer opportunities for improving organ transplantation outcomes. [ABSTRACT FROM AUTHOR]

Chemical looping combustion (CLC) technology offers cost-effective CO2 emission reduction. Coal direct chemical looping (CDCL) emerges as a promising solid fuel CLC technology owing to its ability to directly utilize coal without prior gasification, enhancing system integration and efficiency. Despite significant progress in CDCL, challenges persist, including carbon deposition and insufficient oxidation and reduction of oxygen carriers (OCs). This study conducted a thermodynamic equilibrium analysis of a CDCL combustion reactor using Cantera 3.0, a chemical calculation module developed at the California Institute of Technology. The analysis explored the impact of different temperatures, OC-to-coal molar ratios (θ), and OCs types on combustion products. By employing the minimum Gibbs function method and analyzing intrinsic reaction mechanisms, the study provides insights for predicting and optimizing system performance. Thermodynamic equilibrium analysis revealed that with CuO as the OC, insufficient OC (θ < 0.6) led to Cu as the reduction product, while sufficient OC (0.6 < θ < 1.3) yielded Cu and CuO, and excess OC (θ > 1.3) resulted in Cu2O. To optimize CO2 capture, a molar ratio of θ of at least 1.4 and a temperature of at least 800°C are recommended. When Fe2O3 served as the OC, insufficient OC (θ < 0.45) produced Fe and FeO, while excess OC generated FeO and Fe3O4. Optimal operational performance and CO2 capture efficiency required an OC-to-coal molar ratio exceeding 1.4 and a temperature higher than 700°C. This study demonstrates that in CDCL combustion systems, selecting appropriate OCs, temperatures, and OC-to-coal molar ratios ensures stable and efficient combustion and CO2 capture. These findings offer crucial guidance for optimizing system operation. [ABSTRACT FROM AUTHOR]

Ammonia is a well-known chemical and a rising candidate as hydrogen carrier. Nevertheless, its synthesis process decarbonization is a preliminary target. Since the Haber-Bosch loop is still the best path guaranteeing a high yield and capacity, alternative hydrogen and nitrogen upstream production steps have to be identified. Based on the water electrolysis, Power-to-Ammonia application allows for coupling the high performing traditional production process with renewables. This configuration would minimise the environmental impacts and make a decentralised local production feasible; nevertheless, its competitiveness strictly depends on reducing the electricity demand. Looking for low consumption electrolysis technologies, the work presents high-temperature solid oxide cells as one of the most competitive solutions showing a double operation, as hydrogen generator and as oxygen concentrator, which leads to H 2 –N 2 mixture synthesis with a low energy demand (∼8.5 kWh/kg NH 3) by optimizing the heat recovery and simplifying the plant design. [Display omitted] • Green ammonia production with competitive energy consumptions using solid oxide cells. • Solid oxide cell potentialities working as steam electrolyser and oxygen separator. • Heat management optimization coupling high-temperature cells with Haber-Bosch loop. [ABSTRACT FROM AUTHOR]

Given the pronounced dissolution of electrocatalysts in acidic environments, the quest for effective oxygen evolution reaction (OER) electrocatalysts suitable for proton exchange membrane (PEM) water electrolyzers persists as a formidable challenge. In this investigation, catalysts are synthesized by creating oxygen vacancies within various metal oxides (Nb2O5‐x, Ta2O5‐x, ZrO2‐x, TiO2‐x) through plasma‐assisted method, thereby facilitating the immobilization of IrO2 onto these defect‐rich surfaces. The findings unveil that IrO2/Nb2O5‐x manifests reduced overpotentials during acidic OER, achieving an overpotential down to 225 mV@10 mA cm−2, coupled with outstanding durability at multicurrent densities exceeding 200 h, attributed to strong oxide‐support interaction (SOSI) between the IrO2 catalyst and Nb2O5‐x substrate. Density functional theory (DFT) computations uncover intensified binding affinities between IrO2 and Nb2O5‐x, thus modulating the central energy levels of Ir's d orbitals toward favorable OER conditions, consequently bolstering the electrocatalytic activity and stability of the composite catalyst. Furthermore, employing IrO2/Nb2O5‐x as a PEM electrolyzer anode enables consistent operation at 1000 mA cm−2 for 200 h, with an Ir content of only 0.2852 mg cm−2 and an energy consumption of 4.34 kWh Nm−3 H2. This achievement substantially lowers the cost of hydrogen production to US$ 0.96 per kilogram, underscoring its potential for practical applications. [ABSTRACT FROM AUTHOR]

Lanthanum Strontium Ferrite (LSF), as an oxygen carrier, is used for chemical looping H 2 production and CO 2 utilization. In this work, the first attempt to upscale and understand the heat and mass transfer using 400 g of LSF pellets in a dynamically operated packed bed reactor is carried out. Experiments were conducted at 650–820 °C and 1–5 bar g , evaluating the pellets' reactor heat management, phase stability, and mechanical integrity over 70 h for the high-temperature redox cycling in chemical looping water-gas shift (CL-WGS) and chemical looping reverse water-gas shift (CL-RWGS) reactions. Key results at the reactor scale indicate a maximum cyclic average H 2 O-to-H 2 conversion of 31%, with a peak oxygen carrier capacity for CL-WGS of 0.38 mmol/g LSF. In the case of CL-RWGS, a peak CO 2 -to-CO conversion of 99.8% was achieved, with an oxygen carrier capacity of 0.57 mmol/g LSF. Reactor heat management for exothermic and endothermic redox reactions showed the ability to maintain a high temperature profile where the heat front lagged the reaction front over a 15 cm reactive bed length. A maximum ΔT of 45 °C and 35 °C were observed during the oxidation of the LSF bed with H 2 O and CO 2 , respectively. In the case of air oxidation, a maximum ΔT of 120 °C indicates that the reaction is more exothermic and can be used to raise the temperature of the bed especially if heat is required to sustain the process. No evidence of material performance degradation was recorded over 70 h of testing, maintaining the pellets' operational cyclability, phase stability, and mechanical integrity. The results demonstrate the robustness of the material, and they are encouraging versus the scalability of LSF for chemical looping applications, into H 2 production and CO 2 utilization processes. a) Ideal cubic ABO 3 perovskite framework (red, B-site; grey, A-site; blue, oxygen) b) Chemical looping water-gas shift cycling gas outlet. [Display omitted] • 400 g of LSF tested for WGS and RWGS chemical looping. • Testing campaign in packed bed up to 820 °C and 5 bar. • High LSF stability over 70 h and 35 redox cycles. • Peak CO 2 -to-CO conversion of 51% and H 2 O-to-H 2 conversion of 31%. • Optimum oxygen transfer capacity of 0.95 ± 0.04 mmol O /g LSF at 750 °C. [ABSTRACT FROM AUTHOR]

Chemical looping reforming of methane (CLRM) with Fe‐based oxygen carriers is widely acknowledged as an environmentally friendly and cost‐effective approach for syngas production, however, sintering‐caused deactivate of oxygen carriers at elevated temperatures of above 900 °C is a longstanding issue restricting the development of CLRM. Here, in order to reduce the reaction temperature without compromising the chemical‐looping CH4 conversion efficiency, we proposed a novel operation scheme of CLRM by manipulating the reaction pressure to shift the equilibrium of CH4 partial oxidation towards the forward direction based on the Le Chatelier's principle. The results from thermodynamic simulations showed that, at a fixed reaction temperature, the reduction in pressure led to the increase in CH4 conversion, H2 and CO selectivity, as well as carbon deposition rate of all investigated oxygen carriers. The pressure‐negative CLRM with Fe3O4, Fe2O3 and MgFe2O4 could reduce the reaction temperature to below 700 °C on the premise of a satisfactory CLRM performance. In a comprehensive consideration of the CLRM performance, energy consumption, and CH4 requirement, NiFe2O4 was the Fe‐based OCs best available for pressure‐negative CLRM, especially for an excellent syngas yield of 23.08 mmol/gOC. This study offered a new strategy to address sintering‐caused deactivation of materials in chemical looping from the reaction thermodynamics point of view. [ABSTRACT FROM AUTHOR]

Background: Thalassemias are a group of autosomal recessive disorders and the most common inherited disease worldwide. Fetal hemoglobin (HbF) is the main oxygen carrier protein in the human fetus. Elevated HbF level is known to ameliorate the severity of HbE/β and β-thalassemia. This study aimed to investigate whether two commonly known HbF-associated SNPs (rs28384513 and rs4895441) in the HBS1L-MYB region are associated with HbF level and disease severity in Bangladeshi HbE/β-thalassemia patients. Methods: Blood samples were collected from 160 participants (120 HbE/β-thalassemia patients and 40 healthy controls). Hematological analysis was performed using complete blood count (CBC) and capillary Hb electrophoresis. After genomic DNA extraction, real-time PCR-based high-resolution melting (HRM) for SNP detection, targeting the HBS1L-MYB intergenic region, was done. Results: Patients carrying rs28384513 and rs4895441 SNPs had significantly higher HbF (1.29 ± 1.63 and 1.49 ± 1.7 g/dL, respectively) compared to major allele 'TT' and 'AA' (0.87 ± 1.1 and 1.19 ± 1.65 g/dL, respectively) with a p-value of 0.01 and 0.03, respectively. It has been detected that HbF levels in SNP-carrying patients significantly correlated with the higher transfusion interval (60 days, r = 0.38, p < 0.0001) and age of first transfusion (65 months, r = 0.26, p < 0.0028) in these patients. Further, non-transfusion-dependent patients had the highest HbF level (2.03 ± 2.05 g/dL) compared to transfusion-dependent moderate (0.58 ± 0.78 g/dL) and severe (0.84 ± 1.27 g/dL) patients generating a significant p-value < 0.0001 in One-Way ANOVA test. The minor allele frequencies of rs28384513 (G) and rs4895441 (G) were found to be 0.43 and 0.11 respectively. Conclusion: These findings suggest that SNPs of HBS1L-MYB may have a role in elevated HbF levels and ameliorating disease severity in terms of transfusion in HbE/β-thalassemia patients. [ABSTRACT FROM AUTHOR]

Chemical looping partial oxidation of methane (CLPOM) is a low energy consumption and environmentally friendly new technology that can generate syngas. The main challenge is to find suitable oxygen carriers, which should be highly active, stable, low cost, and eco-friendly. This study found that Fe2SiO4 had good reactivity in the CLPOM process. Thermodynamic calculations were carried out by FactSage8.1 to demonstrate the feasibility of Fe2SiO4 as an oxygen carrier for CLPOM. Fe2SiO4 was prepared by the direct ball milling method and the high-temperature solid-phase synthesis method. The reaction properties of Fe2SiO4 were investigated in the fixed bed reactor. The XRD and FTIR results indicate that Fe2SiO4 can be synthesized successfully through the high-temperature solid-phase synthesis method. The results of fixed bed experiments showed that when the reaction temperature was 980 °C and the reaction time was 28 min, the X C H 4 reached 87%, and the S H 2 and S CO were 70% and 71%, respectively. Subsequently, 20 redox cycle experiments were conducted under the optimal reaction conditions. The results showed that Fe2SiO4 exhibited good reactivity in the first two cycles, and as the reaction progressed, the reduced oxygen carrier could not regain the lattice oxygen, leading to a decline in cyclic performance. This study demonstrates that Fe2SiO4 can couple CO2 and CH4 to produce syngas and is conducive to reducing carbon emissions. [ABSTRACT FROM AUTHOR]

Hydrogen production is essential in the transition to sustainable energy. This study examines two hydrogen production routes, steam methane reforming (SMR) and chemical looping reforming (CLR), both using raw natural gas as feedstock. SMR, the most commonly used industrial process, involves reacting methane with steam to produce hydrogen, carbon monoxide, and carbon dioxide. In contrast, CLR uses a metal oxide as an oxygen carrier to facilitate hydrogen production without generating additional carbon dioxide. Simulations conducted using Aspen HYSYS analyzed each method's performance and energy consumption. The results show that SMR achieved 99.98% hydrogen purity, whereas CLR produced 99.97% purity. An energy analysis revealed that CLR requires 31% less energy than SMR, likely due to the absence of low- and high-temperature water–gas shift units. Overall, the findings suggest that CLR offers substantial advantages over SMR, including lower energy consumption and the production of cleaner hydrogen, free from carbon dioxide generated during the water–gas shift process. [ABSTRACT FROM AUTHOR]

Haemorrhagic shock is a leading cause of death worldwide. Blood transfusions can be used to treat patients suffering severe blood loss but donated red blood cells (RBCs) have several limitations that limit their availability and use. To solve the problems associated with donated RBCs, several acellular haemoglobin-based oxygen carriers (HBOCs) have been developed to restore the most important function of blood: oxygen transport. One promising HBOC is the naturally extracellular haemoglobin (i.e. erythrocruorin) of Lumbricus terrestris (LtEc). The goal of this study was to maximise the portability of LtEc by lyophilising it and then testing its stability at elevated temperatures. To prevent oxidation, several cryoprotectants were screened to determine the optimum formulation for lyophilisation that could minimise oxidation of the haem iron and maximise recovery. Furthermore, samples were also deoxygenated prior to storage to decrease auto-oxidation, while resuspension in a solution containing ascorbic acid was shown to partially reduce LtEc that had oxidised during storage (e.g. from 42% Fe3+ to 11% Fe3+). Analysis of the oxygen equilibria and size of the resuspended LtEc showed that the lyophilisation, storage, and resuspension processes did not affect the oxygen transport properties or the structure of the LtEc, even after 6 months of storage at 40 °C. Altogether, these efforts have yielded a shelf-stable LtEc powder that can be stored for long periods at high temperatures, but future animal studies will be necessary to prove that the resuspended product is a safe and effective oxygen transporter in vivo. [ABSTRACT FROM AUTHOR]

Radiotherapy (RT) is a highly valuable method in cancer therapy, but its therapeutic efficacy is limited by its side effects and tumour radiation resistance. The resistance is mainly induced by hypoxia in the tumour microenvironment (TME). As a nano-oxygen carrier, Haemoglobin-based oxygen carriers (HBOCs) administration is a promising strategy to alleviate tumour hypoxia which may remodel TME to ameliorate radiation resistance and enable RT more effective. In this study, we administered fractionated RT combined with HBOC to treat Miapaca-2 cell and Hela cell xenografts on nude mice. The study found that HBOC relieved hypoxic environment and down-regulate expression of hypoxia-inducible factor-1α (Hif-1α) both in regular (100 mm3) and large (360/400 mm3) tumours. The proliferation and metastasis of tumour tissue also decreased after HBOC application. Nevertheless, in vivo RT combined with HBOC performed more effectively to suppress tumour growth in large tumours than in regular tumours. This is due to more severe hypoxic regions exist in the large solid tumours compared to the regular counterparts, and HBOC administration may be more effective in alleviating hypoxia in large tumours. Thus, HBOC sensitization therapy is more suitable for large solid tumours. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To utilize sidestream dark field video microscopic technology to evaluate the endothelium in a canine hemorrhagic shock and resuscitation model. METHODS: 6 purpose-bred adult dogs were anesthetized, instrumented, and subjected to hemorrhagic shock from September 2021 through June 2022. Each dog was resuscitated with 5 resuscitation strategies in an experimental crossover design study: (1) lactated Ringer's solution (LRS) and hydroxyethyl starch (HES) solution; (2) canine chilled whole blood (CWB); (3) canine fresh frozen plasma (FFP) and packed RBCs (pRBC); (4) canine freeze-dried plasma (FDP) and hemoglobin-based oxygen carrier (HBOC); or (5) HBOC/FDP and canine lyophilized platelets. Sidestream dark field video microscopic evaluation was performed at 5 time points: commencement, after hemorrhage, after shock, after resuscitation (T135), and conclusion (T180). RESULTS: There was a significant difference between the perfused boundary region (PBR) measurements when comparing the LRS/HES resuscitation arm to the CWB and FFP/pRBC resuscitation arms at T180. A significant difference in PBR was appreciated in the LRS/HES arm at T135 and T180 compared to its baseline. No other significant differences in PBR were appreciated when resuscitation arms were compared longitudinally or to each other. CONCLUSIONS: Shelf-stable blood products preserved the endothelial glycocalyx similarly to CWB and pRBC/FFP as evaluated by sidestream dark field video microscopy. Lactated Ringer and HES solutions did not adequately preserve the endothelial glycocalyx compared to CWB and pRBC/FFP. CLINICAL RELEVANCE: Shelf-stable blood products are a viable option to preserve the endothelial glycocalyx when used during hemorrhagic resuscitation in dogs. [ABSTRACT FROM AUTHOR]

Chemical looping gasification (CLG) is an effective technology for efficient utilization of coal, biomass and other fuels. In this work, the detailed mechanism of catalytic decomposition during CLG for toluene, a tar model compound, was studied by using reactive force field molecular dynamics (ReaxFF MD) method. Results show that toluene hardly decomposes at temperature lower than 2000 K. Improving temperature could significantly improve decomposition efficiency but also enhances the polymerization to produce PAHs and soot precursor, with largest molecule weight of 2175 (C177H51, 3000 K, 400 ps). Fe2O3 nanocluster, as oxygen carrier, could improve the decomposition efficiency of toluene and reduce the decomposition temperature. At 2000 K and 200 ps, the catalytic conversion of toluene reaches 60%. A large amount of H2, CO, C2H2 and other small molecular gases are generated during the catalytic decomposition of toluene. At 3000 K, the yield of H2, CO and C2H2 reached 132 %mole, 117 %mole and 40 %mole of toluene, respectively. Meanwhile, polymerization reactions are largely inhibited by Fe2O3 nanocluster and the largest molecule is C20H9O, the weight of which is much lower than soot precursor in thermal decomposition. Kinetic results show that the activated energy of catalytic decomposition is about 74 kJ/mole, which is much lower than thermal decomposition (382 kJ/mole). Detailed reaction mechanism reveals that lattice oxygen on Fe2O3 nanocluster act as the active sites, which enhance the decomposition of toluene. [ABSTRACT FROM AUTHOR]

Oxygen vacancy is the most common type of point defects in functional oxides, and it is known to have profound influence on their properties. This is particularly true for ferroelectric oxides since their interaction with ferroelectric polarization often dictates the ferroelectric responses. Here, we study the influence of the concentration of oxygen vacancies on the stability of ferroelectric domain walls (DWs) in BiFeO3, a material with a relatively narrow bandgap among all perovskite oxides, which enables strong interactions among electronic charge carriers, oxygen vacancies, and ferroelectric domains. It is found that the electronic charge carriers in the absence of oxygen vacancies have essentially no influence on the spatial polarization distribution of the DWs due to their low concentrations. Upon increasing the concentration of oxygen vacancies, charge‐neutral DWs with an originally symmetric polarization distribution symmetric around the center of the wall can develop a strong asymmetry of the polarization field, which is mediated by the electrostatic interaction between polarization and electrons from the ionization of oxygen vacancies. Strongly charged head‐to‐head DWs that are unstable without oxygen vacancies can be energetically stabilized in the off‐stoichiometric BiFeO3−δ with δ ∼ 0.02 where ionization of oxygen vacancies provides sufficient free electrons to compensate the bound charge at the wall. Our results delineate the electrostatic coupling of the ionic defects and the associated free electronic charge carriers with the bound charge in the vicinity of neutral and charged DWs in perovskite ferroelectrics. [ABSTRACT FROM AUTHOR]

Oxygen vacancy is the most common type of point defects in functional oxides, and it is known to have profound influence on their properties. This is particularly true for ferroelectric oxides since their interaction with ferroelectric polarization often dictates the ferroelectric responses. Here, we study the influence of the concentration of oxygen vacancies on the stability of ferroelectric domain walls (DWs) in BiFeO3, a material with a relatively narrow bandgap among all perovskite oxides, which enables strong interactions among electronic charge carriers, oxygen vacancies, and ferroelectric domains. It is found that the electronic charge carriers in the absence of oxygen vacancies have essentially no influence on the spatial polarization distribution of the DWs due to their low concentrations. Upon increasing the concentration of oxygen vacancies, charge‐neutral DWs with an originally symmetric polarization distribution symmetric around the center of the wall can develop a strong asymmetry of the polarization field, which is mediated by the electrostatic interaction between polarization and electrons from the ionization of oxygen vacancies. Strongly charged head‐to‐head DWs that are unstable without oxygen vacancies can be energetically stabilized in the off‐stoichiometric BiFeO3−δ with δ ∼ 0.02 where ionization of oxygen vacancies provides sufficient free electrons to compensate the bound charge at the wall. Our results delineate the electrostatic coupling of the ionic defects and the associated free electronic charge carriers with the bound charge in the vicinity of neutral and charged DWs in perovskite ferroelectrics. [ABSTRACT FROM AUTHOR]

Ferromagnetism in the two‐dimensional limit has become an intriguing topic for exploring new physical phenomena and potential applications. To induce ferromagnetism in 2D materials, intercalation has been proposed to be an effective strategy, which could introduce lattice distortion and unpaired spin into the material to modulate the magnetocrystalline anisotropy and magnetic exchange interactions. To strengthen the understanding of the magnetic origin of 2D material, Cu was introduced into a 2D WO3 through chemical intercalation in this work (2D Cu/WO3). In contrast to the diamagnetic nature of Cu and WO3, room‐temperature ferromagnetism was characterized for 2D Cu/WO3. Experimental and theoretical results attribute the ferromagnetism to the bound magnetic polaron in 2D Cu/WO3, which is consist of unpaired spins from W5+/W4+ with localized carriers from oxygen vacancies. Overall, this work provides a novel approach to introduce ferromagnetism into diamagnetic WO3, which could be applied for a wider scope of 2D materials. [ABSTRACT FROM AUTHOR]

The present study investigated the performance of iron ore mixed with carbide slag (CS) as oxygen carrier in a batch-fluidized bed reactor using Datong bituminous coal as fuel. The effects of mixing mass ratio and reaction temperature on the CLC process of coal were investigated. The results showed that iron ore mixed with carbide slag accelerated the CLC process of coal compared with iron ore alone. Reaction temperature had a crucial effect on carbon conversion of coal, but higher than 900°C resulted in a decreased reactivity of CS-mixed oxygen carrier. Multiple redox cycle tests were also conducted to study the stability of CS-mixed oxygen carrier. It was found that though a continuing decreasing reactivity was observed for CS-mixed oxygen carrier, it still has higher CO2 yield and lower CO yield than those of undecorated one. SEM analysis revealed that sintering occurred on the surface of CS-mixed oxygen carrier, resulting in the deterioration of reactivity. The reason for the promoted performance of CS-mixed iron ore seems to be the catalytic effect of carbide slag on the water-gas shift reaction, converting CO to H2, for H2 is more reactive toward iron ore. [ABSTRACT FROM AUTHOR]

Several strategies have been adopted to enhance the electrochemical features of metal-organic framework structures for water splitting, however, a suitable conditions can effectively boost the electrocatalytic activity. Herein, molybdenum-based zeolite imidazolate frameworks (Mo 2g ZIF-67 and Mo 4g ZIF-67) have been synthesized by solvothermal process and electrocatalytic activity was examined at various elevating temperatures of 1 M KOH electrolyte. Mo 4g ZIF-67 nanorods showed the overpotential (η 10) of 358 mV at 20 °C, which was improved to 221 mV at 80 °C for the oxygen evolution reaction. Mo 4g ZIF-67 nanorods exhibited the Tafel slope of 77 mV dec−1 at 80 °C and followed the Volmer-Heyrovsky mechanism. LSV curves reveal that Mo 4g ZIF-67 nanorods showed a greater current density and a good turnover frequency (TOF) of 221.0 ms−1 at the fixed V RHE of 0.7 V. Similarly, Mo 4g ZIF-67 nanorods revealed the η 10 of 181 and 93 mV at 20 and 80 °C, respectively for the HER process. Mo 4g ZIF-67 nanorods displayed a Tafel slope of 95 mV dec−1 and TOF of 213.50 ms−1. The enhanced electrocatalytic activity may be due to rising temperatures, enhanced electrical conductivity at rising temperatures, well defined nanorods shape and greater ECSA, which provided the active sites and facile the flow of charge carriers for oxygen and hydrogen evolution reaction. The electrocatalyst, Mo 4g ZIF-67 nanorods exhibited a uniform current density during stability tests for 30 h at 20 °C, which was increased at 80 °C. Temperature elevation remarkably enhanced the HER and OER characteristics of the Mo 4g ZIF-67 nanorods and suggested an effective electrocatalyst for water splitting. • Mo 4 gZIF-67 nanorods have been synthesized by solvothermal treatment. • Mo 4g ZIF-67 nanorods showed the η 10 of 221 mV at 80 °C for the OER process. • Mo 4g ZIF-67 nanorods exhibited a Tafel slope of 77 mV dec−1 at 80 °C for OER process. • Mo 4g ZIF-67 nanorods exposed the η 10 of 93 mV at 80 °C for the HER process. • Mo 4g ZIF-67 nanorods displayed a TOF of 213.50 ms−1. [ABSTRACT FROM AUTHOR]

The pairs of Cu2O/CuO and CoO/Co3O4 as the carriers of transferring oxygen and storing heat are essential for the recently emerged high-temperature thermochemical energy storage (TCES) system. Reported research results of Cu2O and CoO oxidation kinetics show that the reaction rate near equilibrium decreases with the temperature, which leads to the negative activation energy obtained using the Arrhenius equation and apparent kinetics models. This study develops a first-principle-based theoretical model to analyze the Cu2O and CoO oxidation kinetics. In this model, the density functional theory (DFT) is adopted to determine the reaction pathways and to obtain the energy barriers of elementary reactions; then, the DFT results are introduced into the transition state theory (TST) to calculate the reaction rate constants; finally, a rate equation is developed to describe both the surface elemental reactions and the lattice oxygen concentration in a grain. The reaction mechanism obtained from DFT and kinetic rate constants obtained from TST are directly implemented into the rate equation to predict the oxidation kinetics of Cu2O without fitting experimental data. The accuracy of the developed theory is validated by experimental data obtained from the thermogravimetric analyzer (TGA). Comparing the developed theory with the traditional apparent models, the reasons why the latter cannot appropriately predict the true oxidation characteristics are explained. The reaction rate is jointly controlled by thermodynamics (reaction driving force) and kinetics (reaction rate constant). Without considering the effect of the reaction driving force, the negative apparent activation energy of Cu2O oxidation is obtained. However, for CoO oxidation, the negative apparent activation energy is still obtained although the effect of the reaction driving force is considered. According to the DFT results, the activation energy of the overall CoO oxidation reaction is negative, but the energy barriers of the elementary reactions are positive. Moreover, according to the first-principle-based rate equation theory, the pre-exponential factor in the kinetic model is dependent on the partition function ratio and decreases with the temperature for the Cu2O and CoO oxidation near equilibrium, which results in the apparent activation energy being slightly lower than the actual value. [ABSTRACT FROM AUTHOR]

Aiming at problems such as low energy utilization efficiency and the high oxygen content of liquid products in the process of conventional biomass conversion to prepare liquid fuels, the deoxygenation pyrolysis technology route of larch based on microwave heating was proposed in this paper. Two kinds of calcium–iron composite oxygen carriers, including Ca2Fe2O5 with iron ore structure and CaFe2O4 with spinel structure, were successfully synthesized. The results showed that the selectivity of ideal products was improved under the action of single iron-based oxygen carriers; however, the deoxygenation effect was undesirable. Under the action of CaFe2O4, the selectivity of aromatics was increased to 27.17% and the selectivity of phenols was decreased to 36.46%, which mainly existed in the form of O1P with low oxygen content. The oxygen content of bio-oil was reduced to 27.70% and the calorific value was increased to 29.05 MJ/kg, thus leading to a great improvement in the quality of liquid products. After the pyrolysis reaction, the Fe2P3/2 XPS peak of CaFe2O4 shifted to a higher binding energy and was characterized as higher valence of iron oxide, which proved its "oxygen grabbing" capacity in microwave pyrolysis. The deoxygenation conversion of larch without an external hydrogen supply was achieved. [ABSTRACT FROM AUTHOR]

Chemical looping combustion (CLC) emerges as a cost-effective CO2 capture technology, demonstrating high competitiveness for both industrial and energy applications. This study explores the synthesis of a Cu-based, praseodymium (Pr)-modified gamma-alumina-supported (20CuPA) oxygen carrier (OC) through the wet impregnation method and investigates its performance in CLC. The characteristics of the synthesized OC were investigated using field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, temperature-programmed reduction analysis, and X-ray diffraction analysis. The CLC of methane gas was performed in a thermogravimetric analyzer (TA-Q50). The oxygen transport capacity (OTC) of the 20CuPA-based OC was investigated for 10 redox cycles. The impact of temperature and time as process variables in determining the OTC of OCs was studied. The TGA results indicated that the most important factor influencing the optimization of the OTC of OCs was time. In comparison to time, temperature had less of an impact on the OTC of 20CuPA-OC. The maximum OTC of 20CuPA-OC, which was 0.0546 mg of O2/mg of OC, was reached using optimized process variables, including a temperature of 800 °C and a time of 3 min. [ABSTRACT FROM AUTHOR]

Elevated fetal hemoglobin (HbF), which is partly controlled by genetic modifiers, ameliorates disease severity in β hemoglobinopathies. Understanding the genetic basis of this trait holds great promise for personalized therapeutic approaches. PubMed, MedRxiv, and the GWAS Catalog were searched up to May 2024 to identify eligible GWAS studies following PRISMA guidelines. Four independent reviewers screened, extracted, and synthesized data using narrative and descriptive methods. Study quality was assessed using a modified version of the Q-Genie tool. Pathway enrichment analysis was conducted on gene lists derived from the selected GWAS studies. Out of 113 initially screened studies, 62 underwent full-text review, and 16 met the inclusion criteria for quality assessment and data synthesis. A total of 939 significant SNP-trait associations (p-value < 1 × 10−5) were identified, mapping to 133 genes (23 with overlapping variant positions) and 103 intergenic sequences. Most SNP-trait associations converged around BCL11A (chr.2), HBS1L-MYB, (chr.6), olfactory receptor and beta globin (HBB) gene clusters (chr.11), with less frequent loci including FHIT (chr.3), ALDH8A1, BACH2, RPS6KA2, SGK1 (chr.6), JAZF1 (chr.7), MMP26 (chr.11), COCH (chr.14), ABCC1 (chr.16), CTC1, PFAS (chr.17), GCDH, KLF1, NFIX, and ZBTB7A (chr.19). Pathway analysis highlighted Gene Ontology (GO) terms and pathways related to olfaction, hemoglobin and haptoglobin binding, and oxygen carrier activity. This systematic review confirms established genetic modifiers of HbF level, while highlighting less frequently associated loci as promising areas for further research. Expanding research across ethnic populations is essential for advancing personalized therapies and enhancing outcomes for individuals with sickle cell disease or β-thalassemia. [ABSTRACT FROM AUTHOR]

With the increasing focus on sustainable development, the exploration of renewable and environmentally friendly resources for product synthesis has become paramount. This study aims to investigate the production of dihydroxystearic acid through the in situ hydrolysis of epoxidized oleic acid. Epoxidation of oleic acid was achieved through the utilization of in situ generated performic acid, resulting in the production of epoxidized oleic acid. The synthesis of performic acid involved the combination of formic acid as an oxygen carrier and hydrogen peroxide as an oxygen donor. A maximum epoxide yield of 65% was attained at an optimum reaction time of 30 min. Hydrochloric acid was found to be the most efficient catalyst. A kinetics study was also done using the genetic algorithm to find the reaction rate of dihydroxystearic acid production. The difference between simulation and experimental results was less than 0.1%, which is insignificant. The findings highlight the potential of utilizing renewable resources for the synthesis of high-value compounds, promoting a greener and more sustainable future. [ABSTRACT FROM AUTHOR]

This work proposed a pyrolysis chemical looping reforming‐two stage regeneration (PCLR‐TR) process with carbon‐negative syngas and biochar poly‐generation，aimed at overcoming challenges in chemical looping gasification. The process effectively separates pyrolysis and reforming, circumventing slow solid–solid reactions and enabling the flexible adjustment of the H2/CO ratio. The two‐stage regeneration ensures improved synchronization of reaction rates across different reactors. The results indicate that manipulation of process parameters allows for flexible adjustment of the H2/CO ratio in syngas (ranging from 1.02 to 3.83). The introduction of CO2 feed in the first stage regeneration reactor reduces the oxygen carrier exothermic intensity in the second stage regeneration reactor by 58%. Optimization results suggest that the generated syngas is compatible with diverse downstream applications, exhibiting a maximum CO2 negative emission of 1.85 kg/kg syngas. The PCLR‐TR system offers a versatile and environmentally friendly solution for the energy and chemical industries. [ABSTRACT FROM AUTHOR]

We present the chemical bonding and electronic properties of liquid methane at temperatures from 2000 to 4000 K and high densities of up to 3.0 g/cm3, calculated using ab initio molecular dynamics simulations in combination with the Mulliken population analysis. Bond-overlap populations and pair distribution functions are studied to investigate the evolution of electron delocalization accompanying atomic structure change as the density is increased. In addition, we also investigated the bandgap energy, electronic density of states, and spatial distribution of electron density. We observed that molecular hydrogen and C‒C bonds are formed after methane dissociates, and then the system undergoes a nonmetal–metal transition coinciding with hydrogen being transformed from the molecular to the atomic state. The C‒C bonds in the system retain covalent character, even at the highest density of 3.0 g/cm3. [ABSTRACT FROM AUTHOR]

An ultra-fast change of the absorption onset for zincblende gallium-nitride (zb-GaN) (fundamental bandgap: 3.23 eV) is observed by investigating the imaginary part of the dielectric function using time-dependent femtosecond pump–probe spectroscopic ellipsometry between 2.9 and 3.7 eV. The 266 nm (4.66 eV) pump pulses induce a large electron–hole pair concentration up to 4 × 10 20 cm − 3 , which shift the transition energy between conduction and valence bands due to many-body effects up to ≈ 500 meV. Here, the absorption onset increases due to band filling while the bandgap renormalization at the same time decreases the bandgap. Additionally, the absorption of the pump-beam creates a free-carrier profile within the 605 nm zb-GaN layer with high free-carrier concentrations at the surface, and low concentrations at the interface to the substrate. This leads to varying optical properties from the sample surface (high transition energy) to substrate (low transition energy), which are taken into account by grading analysis for an accurate description of the experimental data. For this, a model describing the time- and position-dependent free-carrier concentration is formulated by considering the relaxation, recombination, and diffusion of those carriers. We provide a quantitative analysis of optical experimental data (ellipsometric angles Ψ and Δ) as well as a plot for the time-dependent change of the imaginary part of the dielectric function. [ABSTRACT FROM AUTHOR]

Blood transfusions are vital, yet limited shelf‐life and storage conditions of red blood cells (RBCs) hinder their use in emergencies. Hemoglobin‐based oxygen carriers (HBOCs) aim to address these challenges, but previous versions faced clinical setbacks due to safety concerns related to hemoglobin (Hb) extravasation. ZIF‐90, a novel metal–organic framework variant where imidazole‐2‐carboxaldehyde (2‐ICA) is bridged to Zn2+ ions, is explored. Optimizing Zn2+:2‐ICA ratios and Hb concentrations, Hb‐loaded ZIF‐90 nanoparticles (NPs) are synthesized in one‐step and under mild synthesis conditions. These NPs achieve a 25.1% yield, 7.0 mg mL−1 Hb concentration, 70.3% encapsulation efficiency (EE), and 96.4% drug loading. They exhibit a left‐shifted oxygen dissociation curve with p50 of ≈8 mmHg, indicating enhanced oxygen release at lower partial oxygen pressures as compared to native RBCs. This feature makes Hb‐loaded ZIF‐90 NPs suitable for certain medical applications including ischemia‐reperfusion injury management. Furthermore, the impact of two prominent capping agents: polyvinylpyrrolidone and polyethylene glycol (PEG) is assessed. PEG improves 2‐ICA incorporation and stabilizes the ZIF‐90 crystalline phase, albeit with reduced yield, Hb content, and EE. The findings underscore the potential of Hb‐loaded ZIF‐90 NPs as next‐generation HBOCs, offering enhanced uniformity, high Hb content, and efficient oxygen binding and release properties for medical applications. [ABSTRACT FROM AUTHOR]

Under the dual carbon target, circulating fluidized bed boilers are not only a coal-fired power generation technology with great commercial value and development potential for refining enterprises, but also the main source of carbon emissions in refining enterprises. With the development of CFB boiler technology and the increasing capacity of boilers, the problem of poor air-fuel mixing caused by the position and method of inletting feedstock and air during the operation of large industrial CFB boilers has gradually become prominent. In order to improve the combustion efficiency and stability of coal-fired circulating fluidized bed boilers and reduce CO2 emissions, this study developed an Fe-based oxygen carrier based on the principle of OCAC technology, and analyzed the performance of the oxygen carrier on a bubbling bed reactor and a 0.3 MW/h CFB coal-fired reactor. Fe-based oxygen carrier has excellent performance of oxygen absorption and oxygen release, the CO conversion rate can reach more than 88% on the bubbling bed reactor, and reach 52% ~65% on the 0.3 MW/h CFB reactor. The emissions of pollutants such as NOx and SO2 in the flue gas have been reduced. [ABSTRACT FROM AUTHOR]

Sorption-enhanced chemical looping gasification (SECLG) has a favorable ability to produce H 2 -rich syngas without any extra separation process. To comprehensively investigate the performances, the temperature in the fuel reactor (FR) side T FR , molar ratio of steam or CaO to carbon (λ steam/C , λ CaO/C), circulation ratio of oxygen carrier to carbon (λ OC/C) are changed to test their effects on the products. Then the coupling effects on SECLG are deeply analyzed by changing two and three of the operating parameters. Results demonstrate that under fundamental conditions, the sorption enhancement becomes unavailable when the temperature is higher than 775 °C but decreasing λ steam/C and increasing λ OC/C can elevate this critical temperature. Increasing the λ OC/C or λ steam/C can enhance the H 2 concentration first, then weaken H 2 concentration. The maximum value of H 2 concentration is 62.47% when λ OC/C = 0.4 and λ steam/C = 1.9. When the FR temperature is lower than 775 °C, there is an optimal λ OC/C for maximizing the H 2 concentration at a specific temperature. When the temperature is 650 °C, λ OC/C = 0.5 and λ steam/C = 1.9, the maximum value of H 2 concentration can reach 95.73% in SECLG. • A thermodynamic process simulation model of biomass SECLG is established. • The gasification performance of SECLG system is simulated under different conditions. • Coupling effects of two and three parameters are investigated based on this model. • When T FR is 650 °C, λ OC/C = 0.5 and λ steam/C = 1.9, maximum H 2 concentration is 95.73%. [ABSTRACT FROM AUTHOR]

The effects of preparation cond让ions on the properties of oxygen carriers were investigated, and the effects of temperature and reduction degree () on the occurrence of potassium were investigated by HSC Chemistry・ The results showed that the optimal preparation conditions were as follows: the addition of ZrO2 was 30%, the addition of K2CO3 was 5%, and the calcination temperature of oxygen carrier was 800 °C ・ In the case of coal excess, the occurrence form of potassium at high temperature is mainly gaseous potassium elemental K(g)・ When the oxygen carrier content in the system is sufficient or excessive, the main occurrence form of potassium changes to KFeO2 at high temperature ・ And only when the reaction temperature is low and the degree of oxygen carrier reduction is deep, can potassium remain in its original form of KCO. [ABSTRACT FROM AUTHOR]

Development in hemoglobin-based oxygen carriers (HBOCs) that may be used as alternatives to donated blood requires an extensive supply of highly pure hemoglobin (Hb) preparations. Therefore, it is essential to fabricate inexpensive, stable and highly selective absorbents for Hb purification. Molecular imprinting is an attractive technology for preparing such materials for targeted molecular recognition and rapid separations. In this case study, we developed human fetal hemoglobin (HbF)-imprinted polymer beads through the fusion of surface imprinting and Pickering emulsion polymerization. HbF was firstly covalently coupled to silica nanoparticles through its surface-exposed amino groups. The particle-supported HbF molecules were subsequently employed as templates for the synthesis of molecularly imprinted polymers (MIPs) with high selectivity for Hb. After removing the silica support and HbF, the resulting MIPs underwent equilibrium and kinetic binding experiments with both adult Hb (HbA) and HbF. These surface-imprinted MIPs exhibited excellent selectivity for both HbA and HbF, facilitating the one-step isolation of recombinant Hb from crude biological samples. The saturation capacities of HbA and HbF were found to be 15.4 and 17.1 mg/g polymer, respectively. The present study opens new possibilities for designed resins for tailored protein purification, separation and analysis. [ABSTRACT FROM AUTHOR]

The present research describes one of the processes outlined in the literature, known as Chemical Looping Dry Reforming of Methane, which is currently to gain attraction to produce clean fuels from natural gas using a metal oxide support as a catalyst. This two‐step method offers distinct advantages by physically separating the reaction steps. This spatial separation effectively eliminates undesirable side reactions, leading to highly efficient syngas production with minimal carbon deposition. Crucial to optimizing this process is a deep understanding of the oxygen storage capacity (OSC) of the support (oxygen carrier) that will work in synergy with the supported active phase. Among the candidates, praseodymium stands out due to its favourable redox properties and exceptional OSC characteristics, making it a promising option for cleaner fuel technologies. In particular, this study emphasizes the significant influence of the nature of the active phases (Ni, Co or their bimetallic combinations), with bimetallic phases being the most promising (even without reduction, they can exhibit activity that equals or improves that of the Ru as benchmark), underscoring the fundamental role of catalyst design in achieving optimal performance. The results indicate that these compositions have high activities to generate the products, remaining close to the activity of ruthenium and generating minimal coke deposits in one reaction cycle. [ABSTRACT FROM AUTHOR]

Normothermic machine perfusion (NMP) of donor kidneys provides the opportunity to assess and improve organ viability prior to transplantation. This study explored the necessity of an oxygen carrier during NMP and whether the hemoglobin-based oxygen carrier (HBOC-201) is a suitable alternative to red blood cells (RBCs). Porcine kidneys were perfused with a perfusion solution containing either no-oxygen carrier, RBCs, or HBOC-201 for 360 min at 37°C. Renal flow and resistance did not differ significantly between groups. NMP without an oxygen carrier showed lower oxygen consumption with higher lactate and aspartate aminotransferase levels, indicating that the use of an oxygen carrier is necessary for NMP. Cumulative urine production and creatinine clearance in the RBC group were significantly higher than in the HBOC-201 group. Oxygen consumption, injury markers, and histology did not differ significantly between these two groups. However, methemoglobin levels increased to 45% after 360 min in the HBOC-201 group. We conclude that HBOC-201 could be used as an alternative for RBCs, but accumulating methemoglobin levels during our perfusions indicated that HBOC-201 is probably less suitable for prolonged NMP. Perfusion with RBCs, compared to HBOC-201, resulted in more favorable renal function during NMP. [ABSTRACT FROM AUTHOR]

Upscaling of the laboratory oxygen carriers while keeping comparable performance as laboratory powders remains a challenge in the field of chemical looping combustion (CLC). In this work, two perovskite compositions of CaMn0.375Ti0.5Fe0.125O3 (termed CMTF8341) and CaMn0.5Ti0.375Fe0.125O3 (CMTF8431) have been fabricated by means of spray granulation. The fabricated granules were evaluated by redox cycles under CLC conditions and showed comparable performance with laboratory-prepared powders, i.e. high oxygen transfer capacity and fast redox kinetics. Under chemical looping oxygen uncoupling (CLOU) conditions, it has been found that steam leads to a slower kinetics and lower oxygen transfer capacity for these two compositions. When it comes to sulphur effect on the oxygen carriers, redox cycles with deep reduction showed no influence with H2S since the CaSO4 formed in air decompose but it affected the materials under mild CLOU due to calcium sulphate formed under such condition. Nonetheless, redox performance can be recovered by deep reduction with an enhanced oxygen capacity. These two oxygen carriers showed no degradation as compared to other tested minerals in the field of CLC. Microstructure analyses from SEM showed high degree of structure integrity after redox cycles at temperatures up to 1050 °C for the CMTF8341. Good mechanical strength was evidenced from cold attrition test, and the lifetime of the two granules was also predicted based on a standard reference. [ABSTRACT FROM AUTHOR]

Iron or its oxides (FexOy) commonly exist in the ash of fossil fuel and biomass, and are used as oxygen carriers in chemical looping process, and Fe3O4 is a main occurrence. The NO reduction mechanisms by CO over Fe3O4 (111) surface was investigated via density functional theory (DFT) calculations. An optimized unit cell of Fe3O4 was constructed. The interaction between molecules and cell surface was described by the calculated adsorption properties and electronic structures. Results showed that the most stable adsorption of NO/CO belongs to chemisorption and NO has higher adsorption energy than CO. NO can be absorbed onto Fe3O4 surface to form (NO)2 dimer structure, which easily decomposes via a small energy barrier. (NO)2 dimer mechanism is a possible pathway for the reduction of NO by CO over Fe3O4, following three steps: 2NO → (NO)2*, (NO)2* → N2O + O*, O* + CO* → CO2. After the decomposition, the intermediate species N2O molecule and the remaining O atom adsorbed strongly on the Fe3O4 surface can be removed by CO. CO also promotes the gaseous decomposition of N2O. DFT results also showed O2 will prevent NO reduction reaction. The calculated reaction rate constants further verify the existence of (NO)2 dimer mechanism and the rate-limiting step is the removal of the surface O atom. [ABSTRACT FROM AUTHOR]

In this paper, a novel process for synergistic carbon in situ capture and the utilization of blast furnace gas is proposed to produce CO via chemical looping. Through thermodynamic analysis, this process was studied in terms of the carbon fixation rate, CO yield, in situ CO2 utilization rate, CH4 conversion rate and energy consumption. It provides valuable insights for achieving efficient CO2 capture and in situ conversion. FeO and CaO are used as the oxygen carrier and the carbon carrier, respectively. Under the conditions of reaction temperature of 400 °C, pressure of 1 bar and FeO/CO ratio of 1, the carbon capture rate of blast furnace gas can reach more than 99%. In the carbon release reactor, the CO yield is lower than that in the original blast furnace gas (BFG) if no reduction gas is involved. Therefore, methane is introduced as a reducing gas to increase CO yield. When the reaction temperature is increased to 1000 °C, the pressure level is reduced to 0.01 bar and the CH4/C ratio is 1:1 (methane to carbon), the CO yield is four times that of the initial blast furnace gas. Under the optimal conditions, the energy consumption of the system is 0.2 MJ/kg, which is much lower than that of the traditional process. This paper verifies the feasibility of the new process from the perspective of thermodynamics. [ABSTRACT FROM AUTHOR]

Coal-based chemical looping gasification (CCLG) has been proposed as an emergent type of coal gasification technology that produces high-quality syngas by using lattice oxygen from oxygen carrier instead of molecular oxygen. In this paper, the Fe–Ni composite oxygen carrier was synthetized using sol-gel method and the gasification performance of the prepared sample was analyzed by a fixed-bed reactor. The results indicated that the Fe–Ni composite oxygen carrier presented a high carbon conversion of fuel and syngas selectivity during the CCLG process. Additionally, the cycle stability test showed that the carbon conversion of fuel and syngas selectivity did not change significantly with the increase of cyclic frequency. To further study the influence of volatiles released from coal on the gasification performance of oxygen carrier, the interactions between the oxygen carrier samples and char obtained at different pyrolysis temperatures were investigated by a fixed-bed reactor and TG-MS, respectively. The results suggested that the gas products (H 2 , CO, CO 2 and CH 4) yields of char-oxygen carrier were significantly lower than those of coal-oxygen carrier. Besides, the pyrolysis temperature for preparing char had a great effect on the carbon conversion of fuel and syngas selectivity due to the distinction of volatiles released from solid fuel. • Efficient Fe–Ni composite oxygen carrier was crafted via sol-gel method. • Fe–Ni composite oxygen carrier showed good performance with desirable reactivity and cyclic stability. • Interaction between oxygen carrier and volatiles released from coal was investigated. • Char gasification was demonstrated to be the rate determining step during the CCLG process. [ABSTRACT FROM AUTHOR]

The development of Chemical-looping Reforming (CLR) for blue hydrogen production requires a precise reactor design and control to achieve optimal efficiency and operability. This study proposes a 1D heterogeneous model for a CLR fixed-bed reactor, targeting the production of blue hydrogen and nitrogen. Validation against experimental data confirms the model's accuracy and reliability. A comprehensive sensitivity analysis highlights reactor variables, including active metal content in the oxygen carrier, steam-to-methane ratio, and molar flow rates during reduction and reforming stages, as key variables in determining reactor performance. Optimizing these variables is crucial for process intensification and enhancing hydrogen production efficiency. Under optimal conditions, the reactor yields nitrogen with a concentration above 98% during the oxidation stage and hydrogen with a 66.7% concentration during the reforming stage. Moreover, the CLR reactor operates autothermally and reaches a hydrogen production efficiency of 63.6%, prior to any further purification. The study concludes with a discussion of the reactor's challenges and opportunities, laying the groundwork for potential future research and advancements in the field. [Display omitted] • An intensified reactor for efficient blue H 2 and N 2 production is proposed. • Reactor key parameters are active metal, steam-to-methane ratio, and pressure. • Reactor optimization maximizes hydrogen production efficiency. • 66% H 2 yield in reforming and > 98 % N 2 purity in oxidation are achieved. [ABSTRACT FROM AUTHOR]

Aiming at the resource utilization of CO 2 and the value-added catalytic conversion of ethane, different reducibility oxide carriers were used to study. Through catalytic reaction experiments, catalyst characterization and kinetic analysis, the interaction between reducible carriers and active metals and their regulation on the catalytic reaction performance of ethane with CO 2 were revealed. Fe 1.5 Ni 0.5 /CeO 2 has the highest ethylene selectivity of 87% near 650 °C, and is a good catalyst for the CO 2 -assisted ethane oxidative dehydrogenation to ethylene reaction. The strong interaction between the reducible CeO 2 and ZrO 2 carriers and active metals makes the Fe–O–Ce and Fe–O–Zr covalent bonds on the Fe 1.5 Ni 0.5 /CeO 2 and Fe 1.5 Ni 0.5 /ZrO 2 catalysts stronger than Fe–O–Ti and Fe–O–Al covalent bonds on Fe 1.5 Ni 0.5 /TiO 2 and Fe 1.5 Ni 0.5 /γ-Al 2 O 3 catalysts. The lattice oxygen on the reducible catalyst is more readily involved in the reaction. The strong interaction between the active metal and the carrier results in the reduction of the FeO x species and the formation of new active sites, resulting in a high reactivity of the catalyst. The mutually promoted redox cycle between the active species Fe3+/2+-Ni2+/0 and the reducible carrier variable metal Ce4+/3+ species improves the catalytic performance for the reaction of ethane awith CO 2. • Resource utilization of CO 2 and value-added conversion of C 2 H 6 are achieved. • Reducible Fe 1.5 Ni 0.5 /CeO 2 catalyst has the highest ethylene selectivity of 87%. • Lattice oxygen on reducible carrier is more readily involved in the reaction. • Redox cycle between Fe3+/2+-Ni2+/0 and Ce4+/3+ improves catalytic performance. [ABSTRACT FROM AUTHOR]

Green hydrogen is central to the energy transition, but its production often requires expensive materials and poses environmental risks due to the perfluorinated substances used in electrolysis. This study introduces a transformative approach to green hydrogen production via chemical looping, utilizing an iron-based oxygen carrier with yttrium-stabilized zirconium oxide (YSZ). A significant innovation is the replacement of Al2O3 with SiO2 as an inert support pellet, enhancing process efficiency and reducing CO2 contamination by minimizing carbon deposition by up to 700%. The major findings include achieving a remarkable hydrogen purity of 99.994% without the need for additional purification methods. The Fe-YSZ oxygen carrier possesses a significantly higher pore volume of 323 mm³/g and pore surface area of 18.3 m²/g, increasing the pore volume in the iron matrix by up to 50%, further improving efficiency. The catalytic system exhibits a unique self-cleaning effect, substantially reducing CO2 contamination. Fe-YSZ-SiO2 demonstrated CO2 contamination levels below 100 ppm, which is particularly noteworthy. This research advances our understanding of chemical looping mechanisms and offers practical, sustainable solutions for green hydrogen production, highlighting the crucial synergy between support pellets and oxygen carriers. These findings underscore the potential of chemical looping hydrogen (CLH) technology for use in efficient and environmentally friendly hydrogen production, contributing to the transition to cleaner energy sources. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrons rapidly transfer through Fe-O-Bi electronic channels at the interface. • The internal electric field promotes the separation and transfer of charge carriers. • DFT calculation reveals the effect of pollutant structure on photocatalysis rate. • Photolysis rate of FQs is positively correlated with ƒ0 of main active carbon atoms. • MIL-53(Fe)/Bi 4 O 5 I 2 achieves efficient LEV photolysis at different water matrix. Building a heterojunction is a fascinating option to guarantee sufficient carrier separation and transfer efficiency, but the mechanism of charge migration at the heterojunction interface has not been thoroughly studied. Herein, MIL-53(Fe)/Bi 4 O 5 I 2 photocatalyst with a Z-scheme heterojunction structure is constructed, which achieves efficient photocatalytic decontamination under solar light. Driven by the newly-built internal electric field (IEF), the formation of Fe-O-Bi electron migration channel allows for rapid separation and transfer of charge carriers at the heterojunction interface, confirmed by the material characterization and density functional theory (DFT) calculation. The narrower band gap and improved visible light response also contribute to the enhanced photocatalytic activity of composite materials. With levofloxacin as the target pollutant, the optimal MIL-53(Fe)/Bi 4 O 5 I 2 achieves complete removal of pollutant within 150 min, the photocatalysis rate of which is ca. 4.4 and 26.0 times that of pure Bi 4 O 5 I 2 and MIL-53(Fe), respectively. Simultaneously, the optimal composite material exhibits satisfactory photodegradation of seven fluoroquinolones, and the photocatalysis rates are as follows: lomefloxacin > ciprofloxacin > enrofloxacin > norfloxacin > pefloxacin > levofloxacin > marbofloxacin. DFT calculations reveal a positive relationship between degradation rate and Fukui index (ƒ0) of main carbon atoms in seven fluoroquinolones. This study sheds light on the existence of electron migration channels at Z-scheme heterojunction interface to ensure sufficient photoinduced carrier transfer, and reveals the influence of pollutant structure on photolysis rate. [ABSTRACT FROM AUTHOR]

Photocatalysis is a promising route to convert solar light into chemical energy for H 2 evolution and pollutants degradation. Hence, Ni 2 P decorated ZnCr 2 O 4 (Ni 2 P/ZnCr 2 O 4) nanofibers were prepared for boosting solar-light induced water splitting and tetracycline hydrochloride (TCH) degradation. For comparison to ZnCr 2 O 4 nanofibers, Ni 2 P/ZnCr 2 O 4 composites exhibited the better photocatalytic activities for water splitting and TCH removal. Owing to the co-catalytic effect of Ni 2 P for the efficient photon capture, the charge carriers were rapidly separated and migrated at the interface between Ni 2 P and oxygen-defected ZnCr 2 O 4. H 2 evolution rate of optimal C–Ni 2 P/ZnCr 2 O 4 with a nominal Ni 2 P content of 9.0 wt% was 575.89 μmol g−1 h−1, and its apparent quantum yield at 420 nm was 15.25 %, while its H 2 evolution decreased from 2815.13 to 2602.51 μmol g−1 after fifth cycle. In addition, the removal efficiency of C–Ni 2 P/ZnCr 2 O 4 was 93.68 % within 90 min, and declined to 88.76 % after five cycles for solar-light driven degradation of 50 mg L−1 TCH solution. The deactivation of C–Ni 2 P/ZnCr 2 O 4 was due to the photo-corrosion for the change in valence states of compositions. [ABSTRACT FROM AUTHOR]

Biomass, recognized as renewable green coal, is pivotal for energy conservation, emission reduction, and dualcarbon objectives. Chemical looping gasification, an innovative technology, aims to enhance biomass utilization efficiency. Using metal oxides as oxygen carriers regulates the oxygen-to-fuel ratio to optimize synthesis product yields. This review examines various oxygen carriers and their roles in chemical looping biomass gasification, including natural iron ore types, industrial by-products, cerium oxide-based carriers, and core-shell structures. The catalytic, kinetic, and phase transfer properties of iron-based oxygen carriers are analyzed, and their catalytic cracking capabilities are explored. Molecular interactions are elucidated and system performance is optimized by providing insights into chemical looping reaction mechanisms and strategies to improve carrier efficiency, along with discussing advanced techniques such as density functional theory (DFT) and reactive force field (ReaxFF) molecular dynamics (MD). This paper serves as a roadmap for advancing chemical looping gasification towards sustainable energy goals. [ABSTRACT FROM AUTHOR]