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Facile structural modification of α-MnO 2 via single incorporation of Ag element was applied to achieve high-efficiency oxidation removal of benzene, particularly under wet gas. Ag+ ions could enter the MnO 2 structure by partially replacing the tunnel K+ ions, leading to lower crystallinity, smaller crystallite and distorted lattice arrangement. Due to electron transfer from Ag+ to lattice oxygen, Ag decoration weakened Mn-O bonds and the bulk lattice oxygen became more mobile to migrate towards the Ag-MnO 2 surface, resulting in the larger number of surface lattice oxygen. Along with the abundance of oxygen species, the reactivity of surface adsorbed oxygen and lattice oxygen was significantly improved as well by Ag modification. All these factors were favorable to the complete C 6 H 6 -to-CO 2 conversion. Gaseous benzene could be directly oxidized by oxygen species over the pristine MnO 2 catalyst, while the adsorptive activation of gaseous benzene was required for the Ag-MnO 2 before further oxidation. As to the Ag-MnO 2 's endurability of moisture-aroused inactivation, Ag species oppressed water adsorption in the form of strong adsorbate, thus preventing structural damage of the catalyst during humid benzene oxidation. Moreover, water molecules could enhance the "Ag-MnO 2 vs. adsorbed benzene" interaction, which increased the oxidation efficiency of adsorbed benzene. However, the strong binding of water vapor with the MnO 2 surface would cause strong restriction of gaseous benzene from approaching the surface oxygen species, resulting in much less benzene being oxidized under wet gas. [Display omitted] • Ag-MnO 2 catalyst with outstanding water tolerance is obtained for C 6 H 6 oxidation. • Ag destroys MnO 2 lattice arrangement and creates a high coverage of active oxygen. • Water barely affects oxygen activation but enhances "Ag-MnO 2 vs. C 6 H 6 " contact, which elevates wet C 6 H 6 oxidation. • Reaction pathways are elaborated as well for the MnO 2 and Ag-MnO 2 catalysts. [ABSTRACT FROM AUTHOR]

Catalytic oxidation at ambient temperature dominates priority in airborne formaldehyde elimination. Herein, the effects of Li+, Na+ and K+ on the catalytic activity of Ag-CoO x composite were comparatively studied. Systematic methods were applied to investigate the factors influencing catalytic activity. Compared with the cases of Na+ and K+, for which the combination with Ag species respectively deteriorated and limitedly increased formaldehyde removal, the incorporation of Li+ greatly boosted formaldehyde degradation. Characterization results certify that the largest amount of chemically adsorbed active oxygen was crucial to the excellent performance of Li-Ag-CoO x , and the advanced oxidizing property can be rationalized by the strong interaction between the exclusively formed AgCoO 2 and the catalyst parent. This is the first time to clarify the roles of varied alkaline metals in the complete oxidation of formaldehyde catalyzed by Ag-CoO x materials. Effects of process variables were additionally investigated to uncover the catalyst suitability for in-field application. [Display omitted] • Effect of alkaline metals on HCHO oxidation by Ag-CoO x is studied for first time. • Combination of Ag with Li+ greatly elevates the oxidation ability. • Active component AgCoO 2 is formed vIa ion exchange with Li+. • Close contact of AgCoO 2 with catalyst parent creates sufficient chemisorbed oxygen. • Catalytic transformation processes of HCHO are finally raised. [ABSTRACT FROM AUTHOR]

• Paramyosin was the main component of MP from pearl mussel muscle. • MP showed excellent solubility and microstructure as NaCl increased to 0.6 M. • MgCl 2 and CaCl 2 at low replacement level could show acceptable protein properties. • The proper structure unfolding and aggregation of MP were good for its properties. • Partial substitution of NaCl could be an alternative for pearl mussel meat product. The effects of NaCl and its partial substitutes (KCl, MgCl 2 and CaCl 2) on solubility, structural characteristics and aggregation behaviors of myofibrillar protein (MP) from pearl mussel muscle were investigated and compared. MP at 0.6 M NaCl was beneficial to protein unfolding and showed excellent potential functional properties. When NaCl was substituted in low level, MPs also showed good solubility and ordered microstructure as well as NaCl, especially MgCl 2 and CaCl 2 , due to the unfolding of α-helical structures and subsequently exposed tyrosine residues and hydrophobic groups. However, the obviously increased disulfide bonds and hydrophobic interactions in high substitution level indicated the excessive non-sodium salts had negative effects on molecular rearrangement, leading to irregular and overly tight of microstructure. Thus, NaCl partially substituted by KCl, MgCl 2 and CaCl 2 in low substitution level is promising to improve functional properties of MP in low-sodium meat products. [ABSTRACT FROM AUTHOR]

The intercalation of guest molecules into layered materials is an important strategy to develop multifunctional hybrid nanocomposites and porous materials. The unique mesoporous structure and the intrinsic acidity of metal oxide intercalated porous clay heterostructure (PCH) make it a promising catalytic material. In contrast to the current synthesis methods of PCH that have complex procedures and structure-controlling difficulties, a novel one-step approach with supercritical CO 2 (scCO 2 ) as medium was invented using montmorillonite (Mt) as the host matrix and cetyltrimethylammonium bromide as the structure-directing agent (SDA). In this simple and efficient approach, the high diffusivity of scCO 2 ensures the facile transportation of cationic SDA into the interlayer space of Mt via ion exchange, which eliminates a requirement for the high solubility of a SDA in scCO 2 . As a result, the co-assembly of the SDA and the oxide precursor controlled in the interlayer space of Mt leads to the highly ordered PCH. Furthermore, this unique approach provides a general technique to synthesize multi-functional intercalation compounds. [ABSTRACT FROM AUTHOR]