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A thermodynamic model for calculating the mass action concentrations Ni{N_i} of structural units in Fe–Al binary melts based on the atom–molecule coexistence theory, i. e., AMCT–Ni{N_i} model, has been developed and verified to be valid by comparing with reported activities aR,i{a_{{\rm{R, }}i}} of both Al and Fe relative to pure liquid as standard state in Fe–Al binary melts over a temperature range from 1823 to 1973 K (1550 to 1700 °C). Furthermore, Raoultian activity coefficients γi0\gamma _i^0 of both Al and Fe in the Fe-rich corner or Al-rich corner of Fe–Al binary melts as well as the standard molar Gibbs-free energy changes ΔsolGm,i(l)→[i][%i]=1.0Θ,%{\Delta _{{\rm{sol}}}}G_{{\rm{m, }}i{\rm{(l)}} \to {{{\rm{[}}i{\rm{]}}}_{{\rm{ [ \% }}i]{\rm{ = 1}}{\rm{. 0}}}}}^{\Theta {\rm{, \% }}} of dissolved Al or Fe for forming [% Al] or [% Fe] as 1.0 in Fe–Al binary melts have also been determined by the developed AMCT–Ni{N_i} model and verified to be accurate.

The iso-thermal crystallization behavior of phosphate-enriched phase has been experimentally investigated in the rapidly quenched CaO–SiO2–FeO–Fe2O3–P2O5 steelmaking slags under different cooling schedules. The experimental results indicate that increasing endpoint temperature from 1453 to 1533 K and prolonging holding time from 2 to 60 min can result in an increasing tendency of the size of phosphate-enriched phase in the shape of one-dimensional rod. The crystallization kinetics of phosphate-enriched phase in steelmaking slags has been described by Avrami equation. The Avrami constant n$$n$$ was obtained to be 0.472, while the crystallization rate constant k$$k$$ was recommended as lnk=57.40+12,273.96/T−8.25lnT−5.5×10−3T$$\ln k{\rm{= 57}}{\rm{. 40 + 12,273}}{\rm{. 96}}/T - {\rm{8}}{\rm{. 25}}\,\ln T - {\rm{5}}{\rm{. 5}\times{\rm 10}^{- 3}}T$$. Thus, the apparent activation energy E$$E$$ of crystallization is recommended as E=537.60−206.015T$$E{\rm{= 537}}{\rm{. 60}} - {\rm{206}}{\rm{. 015}}T$$ kJ/mol.

A comprehensive effect of Al2O3 content and binary basicity B on the enrichment behavior of phosphates in rapidly quenched CaO-SiO2-FeO-P2O5-Fe2O3-Al2O3 steelmaking slags was investigated through thermodynamic calculations and experimental determination. It is found that the determined mass percentage of P2O5 in the phosphate-enriched phase nC2S-C3P depends on the forming of free C2S in the steelmaking slags and increasing the SiO2 content can result in an obviously decreasing tendency of formed C2S. Adding Al2O3 as a dilute agent for decreasing the viscosity and melting point of the steelmaking slags can be easily bonded with free C2S to form a gehlenite(C2AS) solid solution. Thus,adding Al2O3 in the steelmaking slags can decrease the amount of free C2S in the steelmaking slags,which affects phosphate enrichment. In order to obtain a greater phosphate enrichment in the steelmaking slags,a coupling relationship between the binary basicity B and the mass percentage of Al2O3 in the initial steelmaking slags should be kept as(% Al2O3)=-27.70 + 21.62 B under the conditions of(Al2O3) 〈20.0% and the binary basicity B〉1.3.

Multi-band emission luminescence materials are of great significance owing to their extensive application in diverse fields. In this research, we successfully prepared a series of Pr3+-doped Ca3Al2O6 multi-band emission phosphors via a high-temperature solid-state method. The phase structure, morphology, luminescence spectra and decay curves were investigated in detail. The Ca3Al2O6:Pr3+ phosphors can absorb blue lights and emit lights in the 450–750 nm region, and typical emission bands are located at 488 nm (blue), 525–550 nm (green), 611–614 nm (red), 648 nm (red) and 733 nm (deep red). The influence of the Pr3+ doping concentration was discussed, and the optimal Pr3+ doping concentration was determined. The impacts of charge compensator ions (Li+, Na+, and K+) on the luminescence of Pr3+ were also investigated, and it was found that all the charge compensator ions contributed positively to the emission intensity. More importantly, the emission intensity of the as-prepared phosphors at 423 K can still maintain 65–70% of that at room temperature, and the potential application for pc-LED was investigated. The interesting results indicate that the prepared phosphors may serve multifunctional and advanced applications. [ABSTRACT FROM AUTHOR]

Increasing evidence supports inter‐species transmission of SARS‐CoV‐2 variants from humans to domestic or wild animals during the ongoing COVID‐19 pandemic, which is posing great challenges to epidemic control. Clarifying the host range of emerging SARS‐CoV‐2 variants will provide instructive information for the containment of viral spillover. The spike protein (S) of SARS‐CoV‐2 is the key determinant of receptor utilization, and therefore amino acid mutations on S will probably alter viral host range. Here, to evaluate the impact of S mutations, we tested 27 pseudoviruses of SARS‐CoV‐2 carrying different spike mutants by infecting Hela cells expressing different angiotensin‐converting enzyme 2 (ACE2) orthologs from 20 animals. Of these 27 pseudoviruses, 20 bear single mutation and the other 7 were cloned from emerging SARS‐CoV‐2 variants, including D614G, Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Lambda (B.1.429), and Mu (B.1.621). Using pseudoviral reporter assay, we identified that the substitutions of T478I and N501Y enabled the pseudovirus to utilize chicken ACE2, indicating potential infectivity to avian species. Furthermore, the S mutants of real SARS‐CoV‐2 variants comprising N501Y showed significantly acquired abilities to infect cells expressing mouse ACE2, indicating a critical role of N501Y in expanding SARS‐CoV‐2 host range. In addition, A262S and T478I significantly enhanced the utilization of various mammal ACE2. In summary, our results indicated that T478I and N501Y substitutions were two S mutations important for receptor adaption of SARS‐CoV‐2, potentially contributing to the spillover of the virus to many other animal hosts. Therefore, more attention should be paid to SARS‐CoV‐2 variants with these two mutations. [ABSTRACT FROM AUTHOR]