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With the rapid development of the Internet of Things, smart healthcare, and wearable electronics, there is an increasingly urgent demand for high-performance flexible energy storage devices. Supercapacitors (SCs) have emerged as promising candidates due to their high power density and long cycle life. However, conventional electrode materials often suffer from limited specific capacitance, insufficient mechanical flexibility, and poor long-term cycling stability under flexible conditions, which severely restricts their practical application. To address these challenges, this study aims to develop a novel electrode material that combines high electrochemical performance with excellent mechanical flexibility. By constructing a ternary composite of sulfur-doped graphene oxide (SGO) with two conductive polymers, polyaniline (PANI) and polypyrrole (PPy), a highly conductive hierarchical porous network is formed through the interweaving of mixed nano-sized PANI and PPy. The incorporation of sulfur atoms into SGO effectively enlarges the interlayer spacing of graphene, significantly mitigating the restacking of graphene sheets and thereby exposing more active surfaces. Electrochemical tests demonstrate that the as-prepared SGO/PANI/PPy ternary composite electrode exhibits outstanding performance, delivering a high specific capacitance of 561.8 F & centerdot;g-1. At a power density of 250.62 W & centerdot;kg-1, the device achieves an energy density of 19.51 Wh & centerdot;kg-1. Moreover, the electrode retains 98.12% of its initial capacitance after 10000 consecutive charge-discharge cycles. This work confirms the great potential of the ternary composite as an electrode for flexible supercapacitors and provides new insights into addressing the performance limitations of flexible energy storage devices through multi-component synergy and structural design.

Converter gas is highly susceptible to leakage during the recovery and utilization process, which threatens personnel security and sustainable industrial development. To address this issue, a numerical model was established based on an actual converter fan room, and the accuracy of the simulation was verified through comparison with actual measurement data. In this study, the gas leakage flow field, diffusion trajectories, and hazard zone gradations were analyzed. Results showed that the gas contamination was significantly influenced by the leakage direction, leakage location, and structural boundary. The jet dominated the gas dispersion near the leakage source, with similar initial diffusion characteristics across different scenarios. Then, the diffusion velocity decayed rapidly within a distance of 0.6 m. Obstacles can significantly promote vortex formation, restrict the gas dispersion path, and reduce the extent of the hazardous area. In addition, it can be found that the far-field velocity under downward leakage was the highest, presenting the greatest risk of poisoning. At a height of 1.6 m, a lethal zone with a radius of 0.8 m was formed directly beneath the leakage hole. This work can guide the optimization of the monitoring program and emergency planning for converter gas leakage accidents.

Herein, the final cooling temperatures (FCTs) are the key process parameters to achieve high strength and toughness combination in V-N microalloyed X70 pipeline steels. This research shows that the steels primarily consisted of polygonal ferrite (PF) and a small quantity of pearlite (P) phase at the FCT of 630 degrees C, while the PF and a small fraction of granular bainite (GB) and acicular ferrite (AF) were obtained at 580 degrees C. As the FCTs decrease from 580 degrees C to 450 degrees C, the proportion of AF and GB gradually increases. The AF was composed of fine non-parallel ferrite platelet structures with higher dislocations densities compared with other phases. The nanoscale precipitates were divided into two types under all the FCTs, large-scale Ti(C, N) precipitates of diameter 20-50 nm that precipitated at high temperatures and small V(C, N) precipitates of diameter 5-20 nm at low temperatures, which significantly contributed toward strength-toughness. As the FCTs decrease from 630 degrees C to 450 degrees C, the yield strength -20 degrees C impact energy and drop-weight tear test properties first increased to 565 +/- 7 MPa, 505 +/- 9 J and 99 +/- 1% at 520 degrees C, and finally decreased to 520 +/- 6 MPa, 256 +/- 9 J and 82 +/- 2% at 450 degrees C. The optimum microstructure and mechanical properties were obtained at the FCT of 520 degrees C. The fine-grain strengthening and precipitation strengthening played a crucial role in affecting the thermo-mechanical properties in this steel, such that fine-grain strengthening of 37.5%, and precipitation strengthening of 32.3% at the FCT of 520 degrees C. The transformation strengthening from AF and precipitation hardening from high fraction of 5-20 nm V(C, N) precipitates played a crucial role in improving the low-temperature toughness and strength.

In this study, the thermodynamic conditions governing TiC formation were systematically investigated based on Gibbs free energy and interaction parameter theory. The effects of temperature and furnace atmosphere on interaction parameters were explicitly incorporated, enabling an improved thermodynamic description of TiC formation under realistic blast furnace conditions. Furthermore, compared with conventional two-dimensional equilibrium analyses, a three-dimensional Ti-C-temperature thermodynamic precipitation surface was established to quantitatively evaluate the effects of temperature, titanium content, and carbon content on TiC precipitation behavior. The results indicate that titanium is the dominant controlling factor for TiC formation, while carbon plays a secondary synergistic role. Compared with dissolved carbon, solid carbon provides more favorable thermodynamic conditions, suggesting that TiC preferentially forms via interactions with high-activity carbon sources such as coke or refractory materials. Based on the modified thermodynamic framework and boundary conditions, a quantitative precipitation criterion was established as 100 & times; w[Ti]% + w[C]% >= 10, which ensures TiC precipitation prior to molten iron solidification under representative blast furnace hearth conditions. The proposed criterion provides a practical guideline for titanium addition and carbon regulation in blast furnace ironmaking and improves the thermodynamic prediction capability for titanium-bearing protective phase formation in complex high-temperature metallurgical environments.

Against the backdrop of the “dual carbon” targets, optimizing blast furnace (BF) ironmaking processes is pivotal for realizing low-carbon smelting. Grounded in fundamental ironmaking principles, this study systematically investigates the 2023 production data of 24 large BFs in China (effective volume > 4000 m 3 ) to uncover the intrinsic relationships between the oxygen consumption and its key influencing factors. Practical methods for reducing oxygen consumption are proposed and demonstrated through a case study of a Chinese large BF, whose fuel consumption has been successfully reduced. Analysis reveals that for large BFs over 4000 m 3 , oxygen consumption reduction of 5 m 3 /t yields corresponding reductions of 4.2 kg/t in fuel ratio and 1.6 kg/t in process energy consumption. Both theoretical analysis and operational verification confirm that reducing oxygen consumption is a crucial pathway toward low-carbon and high-efficiency BF smelting.