The Chinese Journal of Process Engineering•2026•DOI: 10.12034/j.issn.1009-606X.225141
This study established a three-dimensional transient gas-liquid two-phase flow model based on a 150-tonne converter to investigate the influence of the number of clogged bottom-blowing elements on the stirring efficiency of the molten pool. The numerical simulation results were validated against actual converter operating conditions. The findings revealed that the primary reason for deteriorated flow characteristics under multiple clogged tuyeres was the overall reduction in stirring energy input from the bottom-blowing gas. Specifically, when the number of clogged tuyeres reached three, the numerically simulated mixing time increased from 150.6 s to 219.3 s, a significant increase of 45.62%. This numerical result was in good agreement with water model experiments, indicating that prompt furnace bottom maintenance and tuyere replacement should be considered under such circumstances. At the same bottom-blowing intensity, the effective stirring area of a single inner-ring tuyere was 0.919 m2, while that of a single outer-ring tuyere was 1.651 m2. The combined effective area achieved through the synergy of inner and outer ring tuyeres was 2.940 m2, which was 14.4% greater than the sum of their individual areas. Clogging disrupted this synergistic stirring effect. A single clogged tuyere had a negligible impact on the distribution of dead zones. However, when tuyeres in both the inner and outer rings were clogged, dead zones became more numerous and concentrated. With 3 and 4 clogged tuyeres, the dead zone volume reached 3.703 and 5.946 m3, accounting for 17.31% and 27.79% of the total molten pool volume, respectively. An industrial plant trial conducted based on the numerical simulation scheme showed that key performance indicators deteriorated as the number of clogged tuyeres increased. With three clogged tuyeres, the average end-point oxygen content reached 0.0669wt%, which was 22.1% higher than that under non-clogged conditions. Concurrently, the total iron content in the slag reached 19.44%, a 24.5% increase compared to the non-clogged baseline.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3405-y
Flexible synaptic devices, as cutting-edge electronic components designed to emulate biological synaptic functions, facilitate parallel information processing and memory storage, thereby significantly enhancing the speed and efficiency of computational operations. Their inherent flexibility allows these devices to seamlessly integrate into a variety of complex environments and application scenarios, including wearable technology, smart skins, and biomedical sensors. Notably, three-terminal flexible synaptic transistors, which structurally resemble biological synapses, offer a more natural and precise emulation of diverse synaptic functionalities. In recent years, substantial progress has been made in the development of these transistors, marking a significant leap forward in neuromorphic electronics. This review comprehensively summarizes the latest advancements in flexible synaptic transistors, providing a systematic analysis of their operational mechanisms, material innovations, and applications in the field of neuromorphic perception systems. Furthermore, it offers insightful perspectives on the future opportunities and challenges that lie ahead for the continued evolution of flexible synaptic transistors.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3555-y
The integration of photochromism and photoluminescence in a single material platform remains constrained by insufficient photostability, slow response kinetics, and limited reversibility. This work reports sodium-doped and sodium/boron co-doped carbon dots (CDs) that exhibit dual-mode photochromic luminescence via a radical-mediated photoinduced electron transfer (PET) mechanism. Na-CDs display a 180 nm red-shift in emission from 450 to 630 nm under 365 nm excitation. Na,B-CDs achieve blue-shifted multicolor emission progressing from orange to yellow and green within 30 s of UV irradiation. The photochromic states spontaneously revert to their initial configurations without external stimuli, and the process remains reversible over multiple cycles. The phenomenon originates from PET between pristine CDs and light-generated anionic radicals. Exploiting these properties, the authors demonstrate reversible anti-counterfeiting systems, information encryption platforms, daylight-responsive UV detection, and plant cell imaging. Na-CDs-PVA films exhibit rapid darkening under sunlight (UV index = 6) and recover after sunset. Na,B-CDs serve as cryptographic security inks for monochrome printing, enabling message decryption through photochromic color changes. Fluorescence imaging of mung bean sprout cells shows blue-to-orange transitions under 365 nm irradiation. These results establish CDs as viable candidates for optoelectronic devices, security labeling, and bioimaging, though long-term photostability and scalable manufacturing remain to be validated.