Analysis of recent measurements of striking changes in the rate of ortho-para conversion of solid H(2) up to 58 GPa shows that the conversion mechanism must differ from that at ambient pressure. A new conversion mechanism is identified in which the emerging excitations are coupled to the converting molecules via electric quadrupole-quadrupole rather than nuclear spin-spin interactions. The latter only initiates conversion while the coupling enhancement associated with the new mechanism is ensured by high compression and a gap closing, with the conversion energy diminishing strongly with increasing pressure.
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http://dx.doi.org/10.1103/PhysRevLett.85.5595 | DOI Listing |
J Phys Chem Lett
January 2025
School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
Electrochemical nitrogen conversion for ammonia (NH) synthesis, driven by renewable electricity, offers a sustainable alternative to the traditional Haber-Bosch process. However, this conversion process remains limited by a low Faradaic efficiency (FE) and NH yield. Although transition metals have been widely studied as catalysts for NH synthesis through effective electron donation/back-donation mechanisms, there are challenges in electrochemical environments, including competitive hydrogen evolution reaction (HER) and catalyst stability issues.
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
Department of Chemistry, Malaviya National Institute of Technology, Jaipur, Jaipur 302017, India.
Herein, a simple ambient conditioned sunlight promoted photochemical reduction reaction is demonstrated for the of nitrate (NO) conversion to ammonia (NH) with the maximum conversion yield of ∼16 mM using iron filings (f-Fe) in the presence of HO. Based on a radical scavenging study of reactive species and the characterization of catalyst f-Fe before and after the reaction, a plausible mechanism has been proposed for the ambient conditioned synthesis of NH. The results associated with the NH synthesis have been verified using the N isotopic labeled nitrate (NO), which supports the simpler viability of the reported procedure.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China. Electronic address:
Residual feed intake (RFI) is a better indicator of feed efficiency than feed conversion ratio (FCR). It is frequently used to evaluate the efficacy of poultry and livestock feed consumption. Generally, Low RFI (LRFI) is associated with better feed conversion efficiency, whereas high RFI (HRFI) suggests poorer feed conversion efficiency.
View Article and Find Full Text PDFArch Biochem Biophys
January 2025
Department of Biochemistry and Center of Excellent in Protein Structure & Function, Faculty of Science, Mahidol University, Bangkok, 14000, Thailand. Electronic address:
Bacterial luciferase (LuxAB) catalyzes the conversion of reduced flavin mononucleotide (FMNH⁻), oxygen, and a long-chain aldehyde to oxidized FMN, the corresponding acid and water with concomitant light emission. This bioluminescence reaction requires the reaction of a flavin reductase such as LuxG (in vivo partner of LuxAB) to supply FMNH⁻ for the LuxAB reaction. LuxAB is a well-known self-sufficient luciferase system because both aldehyde and FMNH⁻ substrates can be produced by the associated enzymes encoded by the genes in the lux operon, allowing the system to be auto-luminous.
View Article and Find Full Text PDFFood Chem
January 2025
Department of Food Science and Technology, Faculty of Agriculture, Ferdowsi University of Mashhad, Azadi Sq., Mashhad, Khorasan Razavi P.O. Box 9177948944, Iran. Electronic address:
Protein fibrillation complex mechanisms led to an emerging trend in research for years. The mechanisms behind whey protein isolate (WPI) fibrillation driven by divalent cations remained still a matter of speculation. All cations (Ca, Fe, Mg, and Zn) enhanced the microenvironment polarity through π-π stacking, and the amide I and II shifts confirmed the fibrillation.
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