The mixing time of molten steel has a decisive impact on the refining efficiency during the RH (Rheinsahl-Heraeus) degassing process. In the present work, a coupled volume of fluid method −discrete phase model has been developed to investigate the effect of bottom injection on mixing and slag layer behaviours in the RH degasser. The fluid flow, mixing characteristic, and the formation of slag eye in the RH degasser with bottom injection are well revealed. Numerical results show that X = −0.75 m (under the up-snorkel) is the optimal injection location to obtain a shortest mixing time, as well as avoid the formation of slag eye in the RH degasser. At the same time, the result of industrial trial shows that the decarburisation efficiency can be accelerated remarkably when the bottom injection is located at X = −0.75 m.

The slit technique is an essential process for narrowing the second-generation high-temperature superconducting tapes (2G-HTS). It is still very challenging to eliminate edge defects introduced during slitting. In this work, we developed a set of reel-to-reel laser slit equipment for narrowing 2G-HTS tapes using a femtosecond infrared laser. In comparison with the commonly used mechanical slit (MS) technique, the laser slit (LS) technique produced no cracks at the tape edges. Electro-mechanical behaviors of 2G-HTS tapes with MS and LS edges were compared in liquid nitrogen conditions. The results of the uniaxial tensile tests showed only a minor difference in irreversible tensile stress/strain of the two kinds of tapes. However, uniaxial tensile fatigue tests showed that the critical current (Ic) retention of the LS tapes was about 14% higher than that of the MS tapes after 104 cycles (@ 77 K, σmax = 0.8σy, and a stress ratio of 0.1). Moreover, U-Spring compressive tests revealed that no irreversible Ic degradation occurred on the LS tapes under compressive strain up to -0.8%, with high reproducibility. On the contrary, the irreversible compressive strains of the MS tapes were rather scattered, ranging from -0.75% to -0.2%. Enhancement of electro-mechanical behaviors is strongly linked to fewer edge defects in the LS tapes. This research demonstrates significant advantages of the laser slit technique over the conventional mechanical slit technique, showing its promising prospects for demanding applications.

Background Recent studies have reported conflicting associations between egg consumption and the risk of all-cause or cardiovascular disease (CVD) mortality, including ischemic heart disease (IHD) mortality and stroke mortality. With accumulating evidence, up-to-date evidence about the association should be synthesized. Objective To assess the association of the risk of all-cause and CVD mortality with egg consumption. Methods We searched PubMed, EMBASE, and Web of Science databases through November 3, 2021 for observational studies conducted in participants ≥18 y of age and provided ORs or RRs or HRs and 95% CIs for ≥3 egg consumption categories or for increased intake of egg with the associations of interest. Random-effects model was used to pool the reported risk estimates. Restricted cubic splines were used to examine the dose–response association. Results Twenty-four articles with 48 reports (25 for all-cause mortality, 11 for CVD mortality, 6 for IHD mortality, and 6 for stroke mortality) involving 11,890,695 participants were included. Intake of each 1 egg/day increment was associated with increased risk of all-cause mortality (RR 1.06; 95% CI 1.02, 1.10; P = 0.008), but the association was restricted to women, Americans, and studies with adjustments for hyperlipidemia. Egg consumption was linearly associated with CVD mortality only in participants >60 y of age, Americans, studies with follow-up duration≥15 years, and adjustments for hyperlipidemia (P ≤0.018). No significant association was found between egg consumption and IHD or stroke mortality (P ≥0.080). Conclusions Egg consumption was linearly associated with a modestly risk of all-cause mortality and, in older participants, Americans, studies with longer follow-up or adjustments for hyperlipidemia, CVD mortality. These findings suggest that it may be prudent to avoid high egg consumption.

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