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Herein, the cerium treatment is used to modify large MnS inclusions in a 303‐ton carbon manganese steel ingot. When the cerium content in steel in the tundish is 90 ppm, the inclusions are CeAlO3 with a small amount of Ce2O2S. The precipitation sequence of inclusions during the solidification and cooling process in the ingot is MgO·Al2O3 + CeAlO3→Ce2S3→MnS→MgS. Due to the inevitable macrosegregation, a small amount of elongated MnS inclusions is precipitated at the radial center. The maximum diameter is 257.80 μm, and the average aspect ratio is 3.28. For heterogeneously nucleated sulfide, the average diameter is less than 13.39 μm, and the average aspect ratio is less than 1.88. The morphology of MnS inclusion is well controlled when the mass ratio of Ce/S in steel is in the range of 0.7–2.8. The average aspect ratio of homogeneously nucleated MnS is less than 1.9. In addition, the formation of CeAlO3 clusters is avoided. According to the atomic mismatch obtained by the edge‐to‐edge matching model, the possibility of heterogeneous nucleation of MnS on the oxide core is CeAlO3 > Ce2O2S > MgO·Al2O3. The Ce2S3 inclusions are mainly precipitated with the core of MgO·Al2O3. [ABSTRACT FROM AUTHOR]

Herein, the fluid flow pattern in a continuous casting slab strand with varied degree of clogging of the submerged entry nozzle is measured using nail boards in industrial trials. The influence of clogging on meniscus velocity, top surface position, surface level fluctuation, and slag entrainment of the strand is investigated. The number density and area fraction of nonmetallic inclusions including Na2O and K2O‐bearing entrained slag ones within the subsurface of steel slabs are inspected using an automatic scanning electron microscope (SEM). The flow pattern in the strand periodically transforms from a double roll flow to a complex flow and/or a single roll flow. The fluid field in the continuous casting mold is unstable and asymmetric under the condition of varied degree of clogging with time. The variation of the meniscus velocity and the surface level fluctuation with time is stochastic. The percentage of >3 mm level fluctuation increases from 4.7% to 10.6% with a serious clogging of the submerged entry nozzle. The amount of entrained slag inclusions with serious clogging is approximately 1.6 times than that with slight clogging. In addition, slag entrainment mechanisms of the shear‐layer instability and the vortex formation are discussed. [ABSTRACT FROM AUTHOR]

Designing an electrocatalyst with excellent performance for both the hydrogen evolution reaction and oxygen evolution reaction in overall water splitting is essential to promote the development of electrolyzed hydrogen production. Defect engineering is a promising method to improve the catalytic performance of target materials. In this study, we used a metal–organic framework as a precursor to establish oxygen-vacancy-rich metal oxide groups supported by a defect-rich carbon framework via calcination. Further, thermal ion exchange was performed to introduce sulfur ions to generate NiCoMnSx−10 with both oxygen vacancies and sulfur defects. Due to the synergistic effect between oxygen vacancies and sulfur defects as well as the good morphology, NiCoMnSx−10 exhibited good catalytic performance at high current densities. The NiCoMnSx−10 cell could achieve a current density of 10 mA cm−2 at a cell voltage of 1.506 V and a current density of 100 mA cm−2 at an overpotential of only 1.94 V, which exceeds that of most materials reported to date. Due to the supporting effect of N, S co-doped carbon, the NiCoMnSx−10 cell maintained stable performance during a 100 h operation at high current. This work provides an innovative method for the preparation of highly efficient electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

It is industrially attractive to produce cyclohexanone directly from gas‐phase oxidative dehydrogenation (ODH) of KA‐oil (a mixture of cyclohexanone and cyclohexanol) since extra alcohol‐ketone separation process can be potentially omitted. Herein, by simply tuning the calcination atmosphere of Pt/SiO2, we successfully regulated the morphology of Pt nanoparticles and optimized their catalytic performance in ODH of KA‐oil. Pt/SiO2 calcined in O2 atmosphere showed a cube‐like morphology and achieved a 78.1 % cyclohexanone yield at 170 °C, which surpassed its counterpart calcined in H2 and most of the reported catalysts. Further experimental and theoretical calculation results indicated that cubic Pt nanoparticles possessed stronger adsorption ability to cyclohexanol and therefore performed better in ODH of KA‐oil. Pt does it again! The morphology of Pt nanoparticles was successfully regulated by calcinating Pt/SiO2 catalysts in different atmospheres and achieved a 78.1 % cyclohexanone yield at 170 °C in oxidative dehydrogenation of KA‐oil. [ABSTRACT FROM AUTHOR]

To study the effect and mechanism of carbon fiber reinforced clay, a series of unconfined compression tests for clay reinforced with carbon fiber have been performed under the conditions of controlled water content and dry density. The carbon fiber is mixed into soil with the quality percentage of 0.01, 0.02, 0.03, 0.05, 0.1, 0.15, 0.25, 0.35, and 0.5%, then a certain quality of water was added in the soil to achieve the optimum soil water content. Ten groups of samples were tested by the unconfined compression experiment. The results showed that the incorporation of carbon fiber elements can effectively improve the unconfined compressive strength and brittle failure mode of soil. The soil is strengthened at the beginning and then weakened with the increased incorporation of carbon fiber, the effect is especially significant when the mix percentage becomes 0.1%. The interaction at the interface between carbon fiber surface and soil matrix is analyzed by using scanning electron microscopy (SEM). It is found that the enhancement mechanisms of carbon fiber reinforced soil are one-dimensional reinforcement of a single carbon fiber thread and three-dimensional reinforcement caused by fiber network respectively. [ABSTRACT FROM AUTHOR]

Oxidative dehydrogenation of KA-oil (a mixture of cyclohexanone and cyclohexanol) is an economically attractive process to produce cyclohexanone because it provides a chance to avoid the energy-intensive alcohol-ketone separation process. The application of this process, however, is hampered by the low cyclohexanone selectivity which results from the competitive adsorption of cyclohexanol and cyclohexanone on the catalyst surface. Herein, by engineering Pt-Bi2O3 interface to tune the geometric and electronic structure of Pt, we successfully weaken the cyclohexanone adsorption without compromising the oxidation of cyclohexanol. As a result, Bi2O3-Pt/SiO2 with Bi-to-Pd ratio of 0.2 exhibits a 5 times higher cyclohexanone selectivity than Pt/SiO2 at the same conversion of KA oil. Long term test suggests that the Pt-Bi2O3 interface is stable in the oxidative dehydrogenation of KA-oil. [ABSTRACT FROM AUTHOR]