NH is a typical alkaline gaseous pollutant widely derived from industrial production and poses great risks to humans and other biota. Metal-organic frameworks (MOFs) have excellent adsorption capacities relative to materials traditionally used to adsorb NH. However, in practice, applications of MOFs as adsorbents are restricted because of its powder form. We prepared a polyamide (PA) macroporous polyester substrate using an emulsion template method and modified the surface with polyethylenimine (PEI) to improve the MOF growth efficiency on the substrate. The difficulty of loading the MOF because of the fast nucleation rate inside the PA macroporous polyester substrate was solved using a stepwise impregnation layer-by-layer (LBL) growth method, and a PA-PEI-MOF303(Al) hierarchical pore composite that very efficiently adsorbed NH was successfully prepared. The PA-PEI-MOF303(Al) adsorption capacity for NH was 16.07 mmol·g at 298 K and 100 kPa, and the PA-PEI-MOF303(Al) could be regenerated repeatedly under vacuum at 423 K. The NH adsorption mechanism was investigated by in situ Fourier transform infrared spectroscopy and by performing two-dimensional correlation analysis. Unlike for the MOF303(Al) powder, the formation of multi-site hydrogen bonds between Al-O-Al/C-OH, N-H, -OH, C=O, and NH in PA-PEI-MOF303(Al) was found to be an important reason for efficient NH adsorption. This study will provide a reference for the preparation of other MOF-polymer composites.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9964625 | PMC |
http://dx.doi.org/10.3390/nano13040727 | DOI Listing |
Adv Sci (Weinh)
November 2024
Research Initiative for Supra-Materials, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, 4-17-1 Wakasato, Nagano-shi, Nagano, 380-8553, Japan.
Increasing the efficiency of visible-light-driven water splitting systems will require improvements in the charge separation characteristics and redox reaction kinetics associated with narrow-bandgap photocatalysts. Although the traditional approach of loading a single cocatalyst on selective facets provides reaction sites and reduces the reaction overpotential, pronounced surface charge carrier recombination still results in limited efficiency increases. The present study demonstrates a significant improvement in the hydrogen evolution activity of the layered single-crystal photocatalyst YTiOS.
View Article and Find Full Text PDFCureus
October 2024
Department of Anesthesiology, Uniformed Services University of the Health Sciences, Bethesda, USA.
Nat Cell Biol
October 2024
Laboratory for Epigenome Inheritance, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.
Facultative heterochromatin is formed by Polycomb repressive complex 2 (PRC2)-deposited H3K27 trimethylation (H3K27me3) and PRC1-deposited H2AK119 mono-ubiquitylation (H2AK119ub1). How it is newly established after fertilization remains unclear. To delineate the establishment kinetics, here we profiled the temporal dynamics of H3K27 dimethylation (H3K27me2), which represents the de novo PRC2 catalysis, in mouse preimplantation embryos.
View Article and Find Full Text PDFJ Assist Reprod Genet
October 2024
Department of Obstetrics and Gynecology, Ankara University School of Medicine, Ankara, 06620, Turkey.
Int J Gynaecol Obstet
September 2024
Department of Obstetrics and Gynecology, Women and Children's Hospital of Chongqing Medical University, Chongqing, China.
Objective: To investigate the influence of inappropriate gestational weight gain (GWG) on pregnancy outcomes in twin pregnant women with in vitro fertilization (IVF) treatment.
Methods: This retrospective cohort study included 2992 twin pregnant women and categorized the participants as follows: (i) they were classified into spontaneous conception (SC) or IVF groups based on whether they received IVF treatment, and (ii) they were categorized into inadequate, optimal, or excessive GWG groups according to the International Organization for Migration Twin Pregnancy Guidelines. Initially, the study investigated the separate effects of IVF treatment and different levels of GWG on the outcomes of twin pregnancies.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!