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The escalating levels of carbon dioxide in flue gas and the resultant greenhouse effect have heightened the need for adsorbents with high CO 2 sorption and separation capabilities. However, Traditional heated synthesis methods are energy-intensive and often involve toxic solvents, which are not viable for widespread industrial use. This study introduces a room-temperature, eco-friendly synthesis technique to produce UiO-66-(OH) 2 with varying amounts of PVP (0/0.1/0.2 g), effectively adjusting the particle morphology. Results confirm that this method maintains robust CO 2 adsorption and selectivity. Notably, the addition of 0.1 g of PVP led to a reduction in pore size and adsorption capacity of CO 2 , yet remarkably enhanced its CO 2 /N 2 separation performance sixfold, outperforming traditional CO 2 adsorbents. Dynamic breakthrough experiments further validated the effectiveness of UiO-66-(OH) 2 in separating binary mixtures of CO 2 /N 2 (v/v = 15/85). The separation performance of UiO-66-(OH) 2 on CO 2 /N 2 was significantly improved after the addition of PVP at room temperature. [Display omitted] • OH-functionalized UiO-66 has been successfully synthesized using green room temperature technology. • The addition of PVP can effectively prevent the agglomeration of UiO-66-(OH) 2 , forming dispersed and uniform particles. • UiO-66-(OH) 2 maintains robust CO 2 adsorption and selectivity, which was synthesized at room temperature. • The CO 2 /N 2 separation of UiO-66-(OH) 2 with the addition of PVP increased to 724. [ABSTRACT FROM AUTHOR]

Numerous efforts have been made in last decade on fully Automated Operational Modal Analysis (AOMA) with field measurement. Considerable user interaction is required especially when parametric system identification methods are involved with Stability Diagrams (SD) for the modal identification. This paper proposes an improved procedure with multi-stage clustering to address this issue. It is generally applicable to any method that relies on SD for the modal identification. The proposed clustering framework offers advantages over traditional AOMA with reduced reliance on the threshold setting in the hierarchical clustering. It relies on hierarchical clustering to identify only one cluster center. This cluster center is then used as input for Max-min distance clustering to achieve adaptive clustering. The proposed Modal Evaluation Index can be employed to eliminate the effect of subjective bias to small dimensional clusters and to assess the validity of each representative mode identified from the cluster. Measured datasets from the Z24 bridge benchmark and the Yingxian wooden pagoda serve to illustrate the performance and effectiveness of this automation strategy. [ABSTRACT FROM AUTHOR]

Toxic Microcystis blooms are widespread in aquatic bodies, posing major threats to aquatic and human life. Recently, bioflocculants have attracted considerable attention as a promising biomaterial for Microcystis management. In search of a novel organism that can produce an efficient bioflocculant for controlling harmful algae sustainably, the native gastropod Cipangopaludina chinensis was co-cultured continuously with toxic Microcystis under different initial algal cell densities. The bioflocculation effect of snail mucus on toxic Microcystis , microcystin removal, and toxin accumulation in snails was investigated. In addition, the properties of the adhesive mucus were characterized using microscopic, X-ray diffraction, infrared spectroscopy, and polysaccharide and proteome analyses. Microcystis cells were captured and flocculated by the snail mucus; removal efficiencies of up to 89.9% and 84.8% were achieved for microalgae and microcystin-leucine arginine (MC-LR), respectively, when co-cultured with C. chinensis for only one day. After nine-day exposure, less than 5.49 µg/kg DW microcystins accumulated in the snails, indicating safety for human consumption. The snail mucus contained 104.3 µg/mg protein and 72.7 µg/mg carbohydrate, which provide several functional groups beneficial for Microcystis bioflocculation. The main monosaccharide subunits of polysaccharides are galactose, galactosamine, glucosamine, fucose, glucose, and mannose. Most of them are key components of polysaccharides in many bioflocculants. Gene Ontology analysis indicated the protein enrichment in binding processes and catalytic activity, which may account for Microcystis bioflocculation via protein binding or enzymatic reactions. The findings indicate that native C. chinensis secretes adhesive mucus that can act as bioflocculant for toxic Microcystis from ambient water and can be an effective and eco-friendly tool for Microcystis suppression. [Display omitted] • Bioflocculants are a promising biomaterial for Microcystis management. • Cipangopaludina chinensis secretes adhesive mucus that can act as bioflocculant. • Effective bioflocculation may be because of active functional groups. • Snail mucus captured and flocculated Microcystis cells, achieving up to 89.9% removal efficiency. [ABSTRACT FROM AUTHOR]

Halomonas spp. are moderately halophilic bacteria with the ability to tolerate various heavy metals. However, the role of basic cellular metabolism, particularly amino acid metabolism, has not been investigated in Halomonas spp. under excess Mn(Ⅱ). The strain Halomonas sp. MNB13 was isolated from a deep-sea ferromanganese nodule and can tolerate 80 mM Mn(Ⅱ). To comprehensively explore the mechanisms underlying its resistance to excess Mn(Ⅱ), we conducted a comparative proteome analysis. The data revealed that both 10 mM and 50 mM Mn(Ⅱ) significantly up-regulated the expression of proteins involved in Mn(Ⅱ) transport (MntE), oxidative stress response (alkyl hydroperoxide reductase and the Suf system), and amino acid metabolism (arginine, cysteine, methionine, and phenylalanine). We further investigated the role of cysteine metabolism in Mn(Ⅱ) resistance by examining the function of its downstream product, H 2 S. Consistent with the up-regulation of cysteine desulfurase, we detected an elevated level of H 2 S in Halomonas sp. MNB13 cells under Mn(Ⅱ) stress, along with increased intracellular levels of H 2 O 2 and O 2 •−. Upon exogenous addition of H 2 S, we observed a significant restoration of the growth of Halomonas sp. MNB13. Moreover, we identified decreased intracellular levels of H 2 O 2 and O 2 •− in MNB13 cells, which coincided with a decreased formation of Mn-oxides during cultivation. In contrast, in cultures containing NaHS, the residual Mn(Ⅱ) levels were higher than in cultures without NaHS. Therefore, H 2 S improves Mn(Ⅱ) tolerance by eliminating intracellular reactive oxygen species rather than decreasing Mn(Ⅱ) concentration in solution. Our findings indicate that cysteine metabolism, particularly the intermediate H 2 S, plays a pivotal role in Mn(Ⅱ) resistance by mitigating the damage caused by reactive oxygen species. These findings provide new insights into the amino acid mechanisms associated with Mn(Ⅱ) resistance in bacteria. • High levels of Mn(Ⅱ) affected the metabolism of certain amino acids in MNB13. • Cysteine desulfurase responsible for H 2 S production was significantly up-regulated. • Increased amounts of H 2 S, H 2 O 2 , and O 2.•− were detected in MNB13 under Mn(Ⅱ) stress • H 2 S restored the growth of MNB13 and reduced H 2 O 2 and O 2.•− intracellular levels • H 2 S decreased the formation of Mn(Ⅱ)-oxides by MNB13. [ABSTRACT FROM AUTHOR]