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In this study, sodium methylsilicate and lime were selected to prepare the same proportion of Imitation Site Soil, and according to the principle of carbonation reaction of restoration materials, the effect of carbonation reaction on the performance of restoration soil of earthen sites was studied. The study has good significance for the conservation and restoration of earthen sites. The samples were cured with CO concentration and curing age as variables. After curing, the samples were tested to determine their water-resistant properties, uniaxial compressive strength, and pH value and a micro scanning electron microscope was used. The results indicated that the carbonation reaction can quickly improve the water resistance and compressive strength of imitation site soil, and reduced the water absorption by 16.67% compared to the specimens conditioned at 0.03% CO concentration. The UCS of specimens at 5%, 10%, and 15% CO concentrations increased by 72.22%, 131.19%, and 219.27%, respectively, compared with those at 0.03% CO concentration after the specimens were environmentally maintained in the carbonation chamber at 0.03%, 5%, 10%, and 15% CO concentrations for 120 h, respectively. The internal particle gradation of the imitation site soil improved after carbonation. These results provide a basis for improving the restoration technology of earthen sites.
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http://dx.doi.org/10.3390/ma15082958 | DOI Listing |
ACS Nano
September 2025
Eastern Institute for Advanced Study, Eastern Institute of Technology, Ningbo, Zhejiang 315200, P. R. China.
Ni-Fe (oxy)hydroxides are among the most active oxygen evolution reaction (OER) catalysts in alkaline media. However, achieving precise control over local asymmetric Fe-O-Ni active sites in Ni-Fe oxyhydroxides for key oxygenated intermediates' adsorption steric configuration regulation of the OER is still challenging. Herein, we report a two-step dealloying strategy to fabricate asymmetric Fe-O-Ni pair sites in the shell of NiOOH@FeOOH/NiOOH heterostructures from NiFe Prussian blue analogue (PBA) nanocubes, involving anion exchange and structure reconstruction.
View Article and Find Full Text PDFInorg Chem
September 2025
Department of Chemistry, Panskura Banamali College, Panskura RS, Purba Medinipur, WB 721152, India.
We report the synthesis and characterization of a new Schiff base ligand (HL), derived from 2-picolylamine and 2-hydroxy-3-methoxy-5-methylbenzaldehyde. Its reaction with Ni(NO)·6HO and Ln(NO)·HO (Ln = Gd, Tb, Dy) in the presence of triethylamine affords a carbonato-bridged family of heterobimetallic NiLn complexes: [NiLn(L)(L')(μ-CO)(NO)]·MeOH·HO (). During the complexation reaction, ligand HL undergoes an oxidation, followed by C-C coupling to generate a secondary ligand (HL').
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Department of Chemistry, Rutgers University-Newark, Newark, New Jersey 07102, United States.
Carbon-hydrogen bond activation is a pillar of synthetic chemistry. While it is generally accepted that Pd is more facile than Ni in C-H activation catalysis, there are no experimental platforms available to directly compare the magnitude of C-H bond weakening between Ni and Pd prior to bond scission. This work presents the first direct measurements of C(sp)-H bond acidity (p) and bond dissociation free energy (BDFE) for a species containing a ligated alkane-palladium interaction (RCH···Pd), also known as an agostic interaction.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
Instituto de Cerámica y Vidrio (ICV-CSIC), C/Kelsen 5, 28049 Madrid, Spain.
The oxygen reduction reaction (ORR) is critical to energy conversion technologies and requires efficient catalysts for superior performance. Herein, nitrogen-doped carbide-derived carbon (N-CDC) catalysts are prepared using novel engineered molecular architectures based on polymer-derived ceramic technology. The obtained catalyst materials show a surface N concentration of >5 wt % and a hierarchically porous structure, resulting in a specific surface area of over 2000 m g.
View Article and Find Full Text PDFJ Chem Phys
September 2025
Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
The formation of carbinolamine represents the crucial initial step in the aldol reaction, specifically involving the interaction between p-nitrobenzaldehyde and acetone, facilitated by amine-catalyzed mesoporous silica nanoparticles (amine-MSN). In this process, a nitrogen atom from propylamine, which acts as the catalytic moiety, engages in the formation of a covalent bond with a carbon atom from acetone, leading to the generation of a carbinolamine intermediate. This reaction is significantly influenced by the presence of silanol groups located on the surface of the amine-MSN, which contribute to the catalytic activity.
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