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From a coordination chemistry perspective, we aimed to advance the knowledge of Sr/Cs separation in the scheme of spent nuclear fuel reprocessing. Based on data mining of crystal structures and deep learning architecture, we summarized and analyzed coordination chemistry properties of Sr/Cs from complex structures(ca. 3.3×104 samples) of 8 alkaline and alkaline earth elements, especially focusing on coordination bond lengths as a representative figure of merit. Applying a Bayesian optimization approach, we were able to establish a high-performing transformer model which could predict the(differential) coordinative affinities toward Sr/Cs of ligand molecules, with exceptional accuracy. As a proof-of-concept, we systematically analyzed ca. 9.1×103 ligand molecules in terms of potential coordinative selectivity toward Sr/Cs and ranked them. In addition, we also determined different contribution of various functional groups for future molecular design of ligands with selectivity. The present study presented fundamental knowledge for coordination chemistry information in the context of radiochemistry and spent nuclear fuel reprocessing, provided guidance and reference for subsequent experiments regarding Sr/Cs separation.

Objective: By analyzing bacteriostasis and efficacy, the possibility of Artemisia argyi extract to be a plant extract preservative is clarified. It provides a message for the development of natural non-irritating plant extract preservative. Methods: Water and ethanol extracts of A. argyi were prepared. The content of its main active components was determined. Its inhibitory effect and stability on Escherichia coli and Staphylococcus aureus were analyzed. Antioxidant activity, ultraviolet absorption capacity and security were also discussed. Results: The ethanol extract of A. argyi had a significant inhibitory effect on the two kinds of bacteria, which was related to the content of active components to some extent. Temperature and UV irradiation had no significant effect on antibacterial activity, while pH had a greater effect on antibacterial activity. At the concentration of 0.96 mg/mL, ethanol extract of A. argyi leaves could eliminate 98% of DPPH and ABTS free radicals, and more than 50% of superoxide anion and hydroxyl free radicals. When the concentration was 0.5 mg/mL, the two extracts had good ultraviolet absorption capacity. The HET-CAM test showed that the extract of A. argyi had high security at the concentration of 62.5 mg/mL. Conclusion: The ethanol extract of A. argyi has good and stable bacteriostatic effect, certain antioxidant activity, ultraviolet absorption performance and security.

The hydraulic conductivity function of unsaturated soil spans several orders of magnitude. Traditional measurement methods often take several months, and it is difficult to measure the hydraulic conductivity in the full suction range. In order to realize the rapid measurement of hydraulic conductivity in the full suction range, the wetting front advancing method is combined with the instantaneous profile method (here referred to as the combined determination method) in this study. A self-developed soil column infiltration device was used to measure the hydraulic conductivity of Qinghai silty clay in the full suction range under different dry densities. The test results show that in the combined determination method, the wetting front advancing method is suitable for the measurement of hydraulic conductivity in the high suction range ( > 25 kPa), while the instantaneous profile method is suitable for measuring the hydraulic conductivity in the low suction range ( ≤25 kPa). The hydraulic conductivity determined by the two methods in the overlapped suction range is basically consistent. The combined determination method can reduce the measurement time of hydraulic conductivity in the full suction range by about one week with good accuracy. In addition, the error sources of the two measurement methods are also analyzed and discussed in this work. The results show that the combined determination method can realize the rapid measurement of hydraulic conductivity in the full suction range, which is expected to make the measurement of the hydraulic conductivity of unsaturated soil become a routine test in soil mechanics.

The utilization of silicomanganese slag (SiMnS) as a precursor for alkali-activated materials (AAMs) is considered as an efficient approach for sustainable and eco-friendly large-scale resource utilization. However, sodium silicate solutions account for more than 50% of the production costs and carbon emissions of AAMs. In this study, AAM activators were prepared by silica-containing waste (acid leaching residue of boron mud, BM-AR) and NaOH as raw materials, and were successfully substituted for commercial sodium silicate-NaOH activators. Results indicated that the NaOH dosage had a great effect on the concentration and modulus of the activator. With the appropriate dosage of NaOH (NaOH: BM-AR = 0.4–0.7), suitable moduli of AAM activators can be produced at a wide range of solid/liquid ratios (L/S = 3–4.5) under mild conditions (80–100 °C). The compressive strength of the SiMnS AAM specimens prepared by this activator can reach 68.58 MPa, and its hydration products were mainly hydrated calcium silicate and amorphous silica–alumina gel, indicating the successful preparation of AAM. Calculation showed that the carbon emission of the AAMs prepared in this study was 12.4% and 37.6% of that of OPC and commercial water glass/NaOH-activated AAMs, and the cost was only 67.14% and 60.78% of them. The process achieves the use of waste materials to replace commercial activators, and is expected to be extended to a variety of AAMs raw materials and silica-containing waste. This makes it a highly promising alternative method for the production of AAMs, particularly the 'just add water' AAMs. [ABSTRACT FROM AUTHOR]

Macrocycles are key tools for molecular recognition and self‐assembly. However, traditionally prevalent macrocyclic compounds exhibit specific cavities with diameters usually less than 1 nm, limiting their range of applications in supramolecular chemistry. The efficient synthesis of giant macrocycles remains a significant challenge because an increase in the monomer number results in cyclization‐entropy loss. In this study, we developed a low‐entropy‐penalty synthesis strategy for producing giant macrocycles in high yields. In this process, long and rigid monomers possessing two reaction modules were condensed with paraformaldehyde via Friedel–Crafts reaction. A series of giant macrocycles with cavities of sizes ranging from 2.0 to 4.7 nm were successfully synthesized with cyclization yields of up to 72%. Experimental results and theoretical calculations revealed that extending the monomer length rather than increasing the monomer numbers could notably reduce the cyclization‐entropy penalty and avoid configuration twists, thereby favoring the formation of giant macrocycles with large cavities. Significantly, the excellent self‐assembly capacity of these giant macrocycles promoted their assembly into organogels. The xerogels exhibited enhanced photoluminescence quantum efficiencies of up to 83.1%. Mechanism investigation revealed the excellent assembly capacity originated from the abundant π–π interactions sites of the giant macrocycles. The outstanding emission enhancement resulted from the restricted nonradiative decay processes of rotation/vibration and improved radiative decay process of fluorescence. This study provides an effective and general method for achieving giant macrocycles, thereby expanding the supramolecular toolbox for host–guest chemistry and assembly applications. Moreover, the intriguing assembly and photophysical properties demonstrate the feasibility of developing novel and unique properties by expanding the macrocycle size. [ABSTRACT FROM AUTHOR]