Microporous silica and silica-alumina powders exhibit a reversible uptake and release of ammonia gas from water vapor containing gas mixtures at ambient temperature, with capacities of 0.9 and 2.0 mmol g-1 in the presence of 100 ppm and 1000 ppm NH3, respectively. The ammonia trapping mechanism was revealed using a combination of direct excitation 1H MAS, 1H-1H EXSY and 1H DQ-SQ NMR spectroscopy, indicating that the major part of the captured ammonia is blended in the hydrogen bonded water network in the pores of the adsorbent. A small fraction is irreversibly bound as result of protonation and chemisorption. While common ammonia adsorbents need thermal regeneration, microporous silica-alumina can be regenerated by sweeping with dry gas at ambient temperature, desorbing the physisorbed fraction together with occluded water. As carbon dioxide does not interfere with the ammonia absorption process, this reversible absorption process of ammonia gas at ambient temperature is particularly attractive for sensor applications.
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Nat Commun
January 2025
Key Laboratory of Luminescence and Optical Information, Ministry of Education, School of Physical Science and Engineering, Beijing Jiaotong University, Beijing, 100044, China.
Magnetic field effects (MFE) of ferromagnetic spin electrocatalysts have attracted significant attention due to their potential to enhance catalytic activity under an external magnetic field. However, no ferromagnetic spin catalysts have demonstrated MFE in the electrocatalytic reduction of nitrate for ammonia (NORR), a pioneering approach towards NH production involving the conversion from diamagnetic NO to paramagnetic NO. Here, we report the ferromagnetic Fe-TiO to investigate MFE on NORR.
View Article and Find Full Text PDFJ Environ Manage
January 2025
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China. Electronic address:
Anaerobic ammonium oxidation (Anammox) has garnered significant attention due to its ability to eliminate the need for aeration and supplementary carbon sources in biological nitrogen removal process, relying on the capacity of anaerobic ammonium oxidizing bacteria (AnAOB) to directly convert ammonium and nitrite nitrogen into nitrogen gas. This review consolidates the latest advancements in AnAOB research, outlining the mechanisms and enzymatic processes of Anammox, and summarizing the molecular biological techniques used for studying AnAOB, such as 16s rRNA sequencing, qPCR, and metagenomic sequencing. Additionally, it also overviews the currently identified AnAOB species and their distinct metabolic traits, while consolidating strategies to improve their performance.
View Article and Find Full Text PDFMicrobiol Spectr
January 2025
College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.
The rumen microbiota plays a vital role in the nutrient metabolism affecting the growth of velvet antler. However, the fermentation patterns and dynamics of the rumen microbiota across growth stages of velvet antler remain largely unexplored. Here, we employed an fermentation approach to assess fermentation parameters and microbial composition in the rumen liquid of sika deer during the early growth (EG), metaphase growth (MG), and fast growth (FG) phases .
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 101408 China. Electronic address:
The exploration of pure organic ultra-long room temperature phosphorescence (RTP) materials has emerged as a research hotspot in recent years. Herein, a simple strategy for fabricating long-afterglow polymer aerogels with three-dimensional ordered structures and environmental monitoring capabilities is proposed. Based on the non-covalent interactions between pectin (PC) and melamine formaldehyde (MF), a composite aerogel (PCMF@phenanthrene) (PCMF@PA) doped with phosphorescent organic small molecules was constructed.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Life Sciences, Henan University, Kaifeng, Henan 475001, China.
Melanoma, a highly aggressive skin cancer, poses significant challenges due to its rapid metastases and high mortality rates. While metformin (Met), a first-line medication for type 2 diabetes, has shown promise in inhibiting tumor growth and metastases, its clinical efficacy in cancer therapy is limited by low bioavailability, short half-life, and gastrointestinal adverse reactions associated with oral administration. In this study, we developed a hollow mesoporous polydopamine nanocomposite (HMPDA-PEG@Met@AB) coloaded with Met and ammonia borane (AB), designed to enable a combined gas-assisted, photothermal, and chemotherapeutic approach for melanoma treatment.
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