The crystal structure of [Cu(4,4'-bipyridine) 2(CF 3SO 3) 2] n metal-organic framework (CuBOTf) of one-dimensional pore networks after pre-evacuation at 383 K was determined with synchrotron X-ray powder diffraction measurement. Effective nanoporosity of the pre-evacuated CuBOTf was determined with N 2 adsorption at 77 K. The experimental H 2 and D 2 adsorption isotherms of CuBOTf at 40 and 77 K were measured and then compared with GCMC-simulated isotherms using the effective nanoporosity. The quantum-simulated H 2 and D 2 isotherms at 77 K using the Feynman-Hibbs effective potential coincided with the experimental ones, giving a direct evidence on the quantum molecular sieving effect for adsorption of H 2 and D 2 on CuBOTf. However, the selectivity for the 1:1 mixed gas of H 2 and D 2 was 1.2. On the contrary, experimental H 2 and D 2 isotherms at 40 K had an explicit adsorption hysteresis, originating from the marked pore blocking effect on measuring the adsorption branch. The blocking effect for quantum H 2 is more prominent than that for quantum D 2; the selectivity for D 2 over H 2 at 40 K was in the range of 2.6 to 5.8. The possibility of the quantum molecular sieving effect for H 2 and D 2 adsorption on [Cu 3(benzene-1,3,5-tricarboxylate) 2(H 2O) 3] n of three-dimensional pore networks was also shown at 77 K.
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Int J Biol Macromol
January 2025
Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea. Electronic address:
This study describes the preparation of novel hybrid aerogels derived from gelatin (Gel), incorporating Br-functionalized zirconium-based metal-organic framework (UiO-66-Br; MOF) as modifying agent to effectively eliminate phosphate and fluoride ions from aqueous environments. The adsorption performance of MOF decorated Gel (Gel-xMOF) hybrid aerogels was investigated under different conditions, including agitation time, adsorbent dosage, solution pH, initial phosphate and fluoride concentrations, coexisting ions, and temperature. The functional groups of the gelatin network, coupled with UiO-66-Br, enhanced the adsorption performance of phosphate and fluoride ions from aqueous solutions.
View Article and Find Full Text PDFBiopolymers
January 2025
School of Pharmacy and Bioengineering, Keele University, Keele, UK.
Cryogels were fabricated by combining polyvinyl alcohol (PVA) and chitosan of varying molecular weights (Mw). In this study, the effects of chitosan Mw, types of boron-containing molecules on network formation, and boron release rate in resulted cryogels were investigated. The PVA/chitosan blend maintained a constant 4.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan Province 610031, China.
Chemical weathering of lithologies with high geochemical backgrounds such as black shale has been proposed to be a critical source for toxic elements in soil and water systems. However, mechanisms controlling the release, migration and enrichment of toxic elements during black shale weathering are poorly understood. This study utilized a suite of micro analytical techniques such as TESCAN integrated mineral analyzer (TIMA), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS) and electron micro-probe analysis (EMPA) to elucidate the intimate relationship between mineralogical transformations and elemental behaviors from profile scale to mineral scale.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Synovial exudation, creeping, and lubrication failure in natural cartilage under a long-term normal loading can be counteracted by a tribo-rehydration (sliding-induced rehydration) phenomenon. Hydrogels, as porous materials, can also restore interfacial lubrication and overcome creep through this strategy. At appropriate sliding velocities, water molecules at the interface contact inlet are driven by hydrodynamic pressures into the porous network to resist creep extrusion.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
School of Materials & Chemistry Architecture, Anhui Agricultural University, Anhui Healthy Sleep Home Furnishings Engineering Research Center, Hefei 230036, China. Electronic address:
Carbon aerogels, characterized by their high porosity and superior electrical performance, present significant potential for the development of highly sensitive pressure sensors. However, facile and cost-effective fabrication of biomass-based carbon aerogels that concurrently possess high sensitivity, high elasticity, and excellent fatigue resistance remains a formidable challenge. Herein, a piezoresistive sensor with a layered network microstructure (BCNF-rGO-CS) was successfully fabricated using bamboo nanocellulose fiber (BCNF), chitosan (CS), and graphene oxide (GO) as raw materials.
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