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Based on industrial production data, the distribution patterns of elements in the oxygen-enriched top-blown Isa smelting process for lead were studied. The focus was on investigating the thermodynamic effects of different slag types and oxygen-enrichment levels on lead content in slag, and analyzing the equilibrium distribution of Pb, S, Fe, and Zn between slag and gas phases in different slag systems, thereby enabling the optimization of the smelting process and improving the lead grade in the slag phase. The optimized parameters obtained from simulation calculations were applied to the actual oxygen-enriched top-blown Isa lead smelting process. The results show that the most suitable smelting parameters are: CaO content of 3.5–4%, SiO2 content of 5.5–6%, SiO2/Fe ratio of approximately 0.9, CaO/SiO2 ratio of approximately 0.3, and oxygen-enrichment level maintained at around 60%. Under these conditions, the lead grade in the slag phase is approximately 50%, representing a relative increase of about 8% compared to that before optimization.

The injection of hydrogen into a blast furnace is a promising technology to fulfill the low-carbon ironmaking purpose. A three-dimensional computational fluid dynamic (CFD) model is developed to investigate the effect of hydrogen injection rate and blast oxygen enrichment rate on the tuyere, raceway, and surrounding coke bed behaviors. It was found that hydrogen injection leads to a higher water vapor volume fraction in the raceway and a higher hydrogen fraction in the coke bed. The magnitude of velocity and temperature near the tuyere only increase slightly due to the cold inlet temperature of hydrogen, which also results in lower coke bed temperature. The volume-averaged temperature decreases from 2146 K to 2129 K when the injection rate increases from 0 to 1000 Nm3/h. Oxygen enrichment rate presents a highly positive correlation with temperature in the raceway and coke bed, water vapor and carbon dioxide volume fraction in the raceway, and pulverized coal burnout rate. Because more carbon participates in the raceway reaction with an increase in oxygen enrichment rate from 0% to 10%, the final carbon monoxide fraction in the coke bed increases from 0.29 to 0.40, and the final hydrogen fraction decreases from 0.15 to 0.13. With the increase in hydrogen injection, the temperature of the raceway and the coke bed decreased slightly. Pulverized coal burnout changes little with the hydrogen injection rate increasing from 500 Nm3/h to 1500 Nm3/h, which is because hydrogen combustion promotes pulverized coal at the front part of the raceway but inhibits it at the end due to the relative lack of oxygen. These results will help better understand the combustion behavior in the tuyere and raceway of the blast furnace with oxygen-rich blast and hydrogen injection.

This work presents novel magnetic mixed cellulose-based matrix membranes that combine the advantages of a low-cost common polymer matrix, such as cellulose acetate (CA), and a low-cost magnetic filler. Moreover, the presented magnetic mixed CA matrix membranes were fabricated and used without applying an external magnetic field during either the membrane casting or the separating process. Poly(methylmethacrylate) and lithium chloride were used in order to improve the mechanical properties and porosity of the fabricated membranes. The iron–nickel magnetic alloys used were prepared through a simple chemical reduction method with unique morphologies (Fe10Ni90—starfish-like and Fe20Ni80—necklace-like). The novel magnetic mixed CA matrix membranes fabricated were characterized using different analysis techniques, including SEM, EDX, XRD, TGA, and FTIR-ATR analyses. Furthermore, the static water contact angle, membrane thickness, surface roughness, tensile strength, and membrane porosity (using ethanol and water) were determined. In addition, vibrating sample magnetometer (VSM) analysis was conducted and the oxygen transition rate (OTR) was studied. The magnetic mixed CA matrix membrane containing starfish-like Fe10Ni90 alloy was characterized by high coercivity (109 Oe) and an efficient 1.271 × 10−5 cm3/(m2·s) OTR compared to the blank CA membrane with 19.8 Oe coercivity and no OTR. The effects of the polymeric matrix composition, viscosity, and compatibility with the alloys/fillers used on the structure and performance of the fabricated mixed CA matrix membranes compared to the previously used poly(ethersufone) polymeric matrix are discussed and highlighted. The novel magnetic mixed CA matrix membranes presented have good potential for use in the oxygen-enrichment process.

In this study, a targeted oxygen-enrichment technology was proposed to enhance coal combustion in an ironmaking blast furnace. The coal flow and combustion characteristics under targeted oxygen-enrichment were investigated using the computational fluid dynamics (CFD) method. The results showed that oxygen utilization and coal burnout were significantly increased under targeted oxygen-enrichment. The coal burnout at 24% O2 concentration was 86.29%, which was the maximum and indicated an increase of 13.13%. However, the cooling effect of room-temperature oxygen had some adverse effects on coal combustion. Given this, the effect of coal particle temperature on coal combustion was investigated based on targeted oxygen-enrichment. The coal combustion process was further enhanced. The coal burnout at a 600 K particle temperature and 25% oxygen concentration was 91.12% and had an increase of 17.96%, which was the maximum.

• We explore here our mechanistic understanding of the environmental and physiological processes that determine the oxygen isotope composition of leaf cellulose (δ18Ocellulose) in a drought-prone, temperate grassland ecosystem. • A new allocation-and-growth model was designed and added to an 18O-enabled soil–vegetation–atmosphere transfer model (MuSICA) to predict seasonal (April–October) and multi-annual (2007–2012) variation of δ18Ocellulose and 18O-enrichment of leaf cellulose (Δ18Ocellulose) based on the Barbour–Farquhar model. • Modelled δ18Ocellulose agreed best with observations when integrated over c. 400 growing-degree-days, similar to the average leaf lifespan observed at the site. Over the integration time, air temperature ranged from 7 to 22°C and midday relative humidity from 47 to 73%. Model agreement with observations of δ18Ocellulose (R² = 0.57) and Δ18Ocellulose (R² = 0.74), and their negative relationship with canopy conductance, was improved significantly when both the biochemical 18O-fractionation between water and substrate for cellulose synthesis (ϵbio, range 26–30‰) was temperature-sensitive, as previously reported for aquatic plants and heterotrophically grown wheat seedlings, and the proportion of oxygen in cellulose reflecting leaf water 18O-enrichment (1 – p ex pₓ, range 0.23–0.63) was dependent on air relative humidity, as observed in independent controlled experiments with grasses. • Understanding physiological information in δ18Ocellulose requires quantitative knowledge of climatic effects on p ex pₓ and ϵ bio.

The raceway adiabatic flame temperature (RAFT) is the basis for judging the thermal state of the hearth and an important parameter for the blast furnace (BF) operation. However, the traditional model fails to accurately characterize the actual RAFT suitable for H 2 -rich gas injection BF. In this study, a RAFT heat balance model suitable for BF with injection of H 2 -rich gas (shale gas, coke oven gas and H 2 ) was optimized. The influences of the H 2 concentrations in tuyere gases, O 2 enrichment ratio, pulverized coal injection (PCI) quantity and blast humidity on RAFT were calculated and the mathematical formula was set up through multiple linear regression. The results show that with the injection rate of coke oven gas, H 2 and shale gas, the RAFT decreases at a rate of 10.4 ℃ per kg, 14.7 ℃ per kg and 5.92 ℃ per kg, respectively. In addition, RAFT increases with the increase of oxygen enrichment ratio, while decreases with the increase of PCI quantity and blast humidity. Changing the oxygen enrichment ratio, PCI quantity and blast humidity can modulate RAFT when the H 2 -rich gas is injected into BF. This work provides a reference for the H 2 -rich gas injection BF. Graphical Abstract

The NSGA-II algorithm was used to establish a multi-objective optimization model for the oxygen enrichment rate of a blast furnace in terms of achieving a lower fuel ratio and higher pulverized coal ratio. The model has the hearth temperature as the constraint condition and the oxygen enrichment rate as the decision variable. The NSGA-II algorithm was used to obtain the Pareto optimal solution of the multi-objective optimization scheme. The prediction effect of the optimization scheme was then tested in industrial experiments. The results show that the optimal setting of the oxygen enrichment rate predicted by the model was 2.70%, which provides an optimal fuel ratio and pulverized coal ratio of 553.86 kg·tHM−1 and 144.58 kg·tHM−1, respectively. In actual production, when the oxygen enrichment rate was set at 2.71%, an optimal fuel ratio and pulverized coal ratio of 553.74 kg·tHM−1 and 148.73 kg·tHM−1 were obtained. The relative error in the oxygen enrichment rate between the model prediction and the actual prediction was 0.003%. The prediction results of the model suggest a reduction in CO2 emissions by 25,770.71 tons per year. The CO2 emission reduction in actual production was approximately 1.09 times the prediction of the model.

Developing eco-friendly catalysts for effective water purification with minimal oxidant use is imperative. Herein, we present a metal-free and nitrogen/fluorine dual-site catalyst, enhancing the selectivity and utilization of singlet oxygen ( 1 O 2 ) for water decontamination. Advanced theoretical simulations reveal that synergistic fluorine-nitrogen interactions modulate electron distribution and polarization, creating asymmetric surface electron configurations and electron-deficient nitrogen vacancies. These properties trigger the selective generation of 1 O 2 from peroxymonosulfate (PMS) and improve the utilization of neighboring reactive oxygen species, facilitated by contaminant enrichment at the fluorine-carbon Lewis-acid adsorption sites. Utilizing these insights, we synthesize the catalyst through montmorillonite (MMT)-assisted pyrolysis (NFC/M). This method leverages the role of MMT as an in-situ layer-stacked template, enabling controlled decomposition of carbon, nitrogen, and fluorine precursors and resulting in a catalyst with enhanced structural adaptability, reactive site accessibility, and mass-transfer capacity. The NFC/M demonstrates an impressive 290.5-fold increase in phenol degradation efficiency than the single-site analogs, outperforming most of metal-based catalysts. This work not only underscores the potential of precise electronic and structural manipulations in catalyst design but also advances the development of efficient and sustainable solutions for water purification. Developing eco-friendly catalysts for effective water purification with minimal oxidant use is imperative. Here, authors present a metal-free and nitrogen/fluorine dual-site catalyst, enhancing the selectivity and utilization of singlet oxygen for sustainable water decontamination.

Tuning the local reaction environment is an important and challenging issue for determining electrochemical performances. Herein, we propose a strategy of intentionally engineering the local reaction environment to yield highly active catalysts. Taking Pt δ− nanoparticles supported on oxygen vacancy enriched MgO nanosheets as a prototypical example, we have successfully created a local acid-like environment in the alkaline medium and achieve excellent hydrogen evolution reaction performances. The local acid-like environment is evidenced by operando Raman, synchrotron radiation infrared and X-ray absorption spectroscopy that observes a key H 3 O + intermediate emergence on the surface of MgO and accumulation around Pt δ− sites during electrocatalysis. Further analysis confirms that the critical factors of the forming the local acid-like environment include: the oxygen vacancy enriched MgO facilitates H 2 O dissociation to generate H 3 O + species; the F centers of MgO transfers its unpaired electrons to Pt, leading to the formation of electron-enriched Pt δ− species; positively charged H 3 O + migrates to negatively charged Pt δ− and accumulates around Pt δ− nanoparticles due to the electrostatic attraction, thus creating a local acidic environment in the alkaline medium. While catalysts have intrinsic activities toward reactions, such performances often require further optimization. Here, authors engineer an acid-like environment in alkaline media by fine-tuning the reaction environment of platinum nanoparticles on oxide nanosheets for H 2 evolution electrocatalysis.

The Indo-Pacific Warm Pool (IPWP) exerts a dominant role in global climate by releasing huge amounts of water vapour and latent heat to the atmosphere and modulating upper ocean heat content (OHC), which has been implicated in modern climate change 1 . The long-term variations of IPWP OHC and their effect on monsoonal hydroclimate are, however, not fully explored. Here, by combining geochemical proxies and transient climate simulations, we show that changes of IPWP upper (0–200 m) OHC over the past 360,000 years exhibit dominant precession and weaker obliquity cycles and follow changes in meridional insolation gradients, and that only 30%–40% of the deglacial increases are related to changes in ice volume. On the precessional band, higher upper OHC correlates with oxygen isotope enrichments in IPWP surface water and concomitant depletion in East Asian precipitation as recorded in Chinese speleothems. Using an isotope-enabled air–sea coupled model, we suggest that on precessional timescales, variations in IPWP upper OHC, more than surface temperature, act to amplify the ocean–continent hydrological cycle via the convergence of moisture and latent heat. From an energetic viewpoint, the coupling of upper OHC and monsoon variations, both coordinated by insolation changes on orbital timescales, is critical for regulating the global hydroclimate. Geochemical proxies from 360,000-year-old sediment cores and numerical simulations are used to show that the upper ocean heat content of the Indo-Pacific Warm Pool greatly affects the Asian monsoon hydroclimate.