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The temperature of molten steel slag produced by the steelmaking process is 1500°c~1700°c, and the total amount of energy contained is considerable. Therefore, the efficient recovery and utilization of sensible heat of steel slag has always been the focus of attention of the metallurgical field all over the world. However, at present, the average recovery rate of waste heat resources per ton of steel in China's iron and steel industry is less than 26%, while the sensible heat recovery rate of various molten slag (including steel slag) is only 1.6%. There are huge room and a broad market for improvement.

The effect of peak temperatures on the grain growth, microstructure transformation and Vickers hardness of the weld coarse grain heat-affected zone (CGHAZ) of SA508 Gr.4N steel for nuclear reactor pressure vessel was studied. The results show that different t8/5 time has no obvious effect on grain growth at the same peak temperature, but different peak temperatures have a great influence. The higher the peak temperature, the more obvious the effect on grain growth. The grain size distribution at different peak temperatures and t8/5 time conforms to the Gaussian normal distribution curve, and a grain growth model suitable for CGHAZ of SA508 Gr.4N steel has been established. The room temperature martensite structure can be obtained by treatment at different peak temperatures and t8/5 time. At the same peak temperature, there is no significant difference in martensite structure at different t8/5 time, and the size of martensite lath only increases with the increasing peak temperatures. At different peak temperatures and t8/5 time, grain size has less effect on the Vickers hardness, which is closely related to the room temperature microstructure of the material. [ABSTRACT FROM AUTHOR]

Herein, the effects of varying austenitizing times on the microstructure and mechanical properties of Cr‐Ni‐Mo‐V series high‐strength steel are investigated, discussing the mechanisms that enhance strength and toughness. By controlling the austenitizing duration, the microstructure during subsequent heat treatments is improved, leading to enhanced overall mechanical properties. The experimental steel undergoes treatments at different austenitizing times, and the microstructure is characterized using optical microscopy, energy‐dispersive spectroscopy, field emission scanning electron microscopy, and X‐ray diffraction. Mechanical properties are assessed through tensile testing, impact testing, and microhardness measurements. The results indicate that, when comparing an austenitizing time of 1 to 1 h and 15 min, the ultimate tensile strength decreases by 10%, microhardness reduces by 78.2 HV, elongation increases by 1.39 times, and toughness improves by 80%. The enhancement in toughness is primarily attributed to the synergistic effect of tempered martensite and bainite within the microstructure. Fracture morphology analysis reveals that variations in austenitizing time affect carbide distribution, accelerate carbide dissolution, decrease the crack growth zone, and enhance toughness. This study provides valuable insights for designing Cr‐Ni‐Mo‐V series high‐strength steels with optimal strength‐toughness synergies. [ABSTRACT FROM AUTHOR]

Dephospho-CoA kinases (DPCKs) are members of the kinase family that catalyze the final step in CoA biosynthesis. Their function is phosphorylation of the 3-hydroxyl group of the ribose using ATP as a phosphate donor. Structural changes induced by ATP binding play an important role during the DPCK catalytic cycle. In this work, DPCK from Legionella pneumophila was overexpressed in Escherichia coli. The purification, crystallization and preliminary X-ray analysis of crystals of this protein are described. The protein was crystallized in space group P21212, with unit-cell parameters a = 36.29, b = 82.20, c = 81.80 Å, using the hanging-drop vapour-diffusion method. Diffraction data were collected at 100 K and the phases were determined using the molecular-replacement method. [ABSTRACT FROM AUTHOR]

The purpose of this study is to provide a culture for mouse bone marrow-derived macrophages (BMDM) and peritoneal macrophages (PM) and to characterize their molecular and cellular biology. The cell number and purity from the primary culture were assessed by cell counter and flow cytometry, respectively. Morphological features were evaluated by inverted microscope. Phagocytosis by macrophages was detected by the neutral red dye uptake assay. Phenotypic markers were analyzed by real-time fluorescent quantitative PCR. Our results show that the cell number was much higher from culture of BMDM than PM, while there was no significant difference regarding the percentage of F4/80+CD11b+ cells (98.30%±0.53% vs. 94.83%±1.42%; P>0.05). The proliferation rate of BMDM was significantly higher than PM in the presence of L929 cell conditioned medium, by using CCK-8 assay. However, PM appeared to adhere to the flask wall and extend earlier than BMDM. The phagocytosis capability of un-stimulated BMDM was significantly higher than PM, as well as lipopolysaccharide (LPS)-stimulated BMDM, except the BMDM stimulated by low dose LPS (0.1 μg/mL). Furthermore, Tnfα expression was significantly higher in un-stimulated BMDM than PM, while Arg1 and Ym1 mRNA expression were significantly lower than PM. The expression difference was persistent if stimulated by LPS+IFN-γ or IL-4. Our data indicate that bone marrow can get larger amounts of macrophages than peritoneal cavity. However, it should be aware that the molecular and cellular characteristics were different between these two culture systems.