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In this paper, the possibility of retreated lithium slag (RTLS) with a high content of alkali, sulfate and fluoride as a partial replacement for fly ash (FA) to produce autoclaved aerated concrete (AAC) was investigated. The influence of the RTLS dosage on the AAC performance were examined. The composition and microstructure of hydrates as well as the microstructure of the RTLS-FA-based AAC compositions were determined by XRD, FTIR, TG-DSC and SEM. The results illustrated that the incorporation of RTLS changed the crystal structure and the microstructure of the tobermorite. With increased RTLS contents, the morphology of tobermorite was changed, and the grass-like tobermorite gradually transformed into network-like tobermorite. The newly formed tobermorite improved the mechanical performance of the AAC. Compared with the RTLS10, the content of tobermorite in the RTLS30 increased by 8.6%. [ABSTRACT FROM AUTHOR]

Recently, we have demonstrated a method to record the longitudinal phase-space distribution of a pulsed cryogenic buffer gas cooled beam of barium fluoride molecules with high resolution. In this paper, we use this method to determine the influence of various source parameters. Besides the expected dependence on temperature and pressure, the forward velocity of the molecules is strongly correlated with the time they exit the cell, revealing the dynamics of the gas inside the cell. Three observations are particularly noteworthy: (1) The velocity of the barium fluoride molecules increases rapidly as a function of time, reaches a maximum 50–200 µ s after the ablation pulse and then decreases exponentially. We attribute this to the buffer gas being heated up by the plume of hot atoms released from the target by the ablation pulse and subsequently being cooled down via conduction to the cell walls. (2) The time constant associated with the exponentially decreasing temperature increases when the source is used for a longer period of time, which we attribute to the formation of a layer of isolating dust on the walls of the cell. By thoroughly cleaning the cell, the time constant is reset to its initial value. (3) The velocity of the molecules at the trailing end of the molecular pulse depends on the length of the cell. For short cells, the velocity is significantly higher than expected from the sudden freeze model. We attribute this to the target remaining warm over the duration of the molecular pulse giving rise to a temperature gradient within the cell. Our observations will help to optimize the source parameters for producing the most intense molecular beam at the target velocity. [ABSTRACT FROM AUTHOR]

• The OPP structure can operate in the violet light band. • The OPP structure realizes an angle selection within 30° range. • The OPP structure provides a new method to realize angle selection through ENZ principle. • The OPP structure can enhance angle selection sensitivity by incorporating dynamic anti-reflection structures. In this paper, an optical privacy protection (OPP) structure is designed for violet light, leveraging the unique epsilon-near-zero (ENZ) properties of YaBa 2 Cu 3 O 7 material along with an anti-reflection structure. To tackle the challenges posed by temperature regulation constraints, the zinc fluoride barium lanthanum aluminum magnesium hexafluoride glass is incorporated as the background medium. The findings indicate that this proposed configuration demonstrates a remarkable transmissivity exceeding 91 % in the TM wave for angles ranging from −30°∼ 30°. It is worth noting that the transmittance significantly drops close to zero beyond –33.7° or 33.7° angles. Moreover, an impressive transmittance of over 98 % is achieved within the TE wave range of −30°∼ 30°, while experiencing a sharp decline towards nearly zero beyond –33.9° or 33.9° angles. The designed OPP effectively operates across the frequency range of 680 ∼ 790 terahertz, encompassing the violet optical spectrum. It consistently exhibits a rectangular coefficient exceeding 0.84 in the TE wave and surpasses 0.87 in the TM wave, demonstrating its exceptional performance characteristics within these respective modes. [ABSTRACT FROM AUTHOR]