Methane hydrate is an icelike substance that is stable at high pressure and low temperature in continental margin sediments. Since the discovery of a large number of gas flares at the landward termination of the gas hydrate stability zone off Svalbard, there has been concern that warming bottom waters have started to dissociate large amounts of gas hydrate and that the resulting methane release may possibly accelerate global warming. Here, we corroborate that hydrates play a role in the observed seepage of gas, but we present evidence that seepage off Svalbard has been ongoing for at least 3000 years and that seasonal fluctuations of 1° to 2°C in the bottom-water temperature cause periodic gas hydrate formation and dissociation, which focus seepage at the observed sites.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1126/science.1246298 | DOI Listing |
Nat Commun
January 2025
Institute of Biomedical Engineering, College of Life Sciences, Qingdao University, Qingdao, China.
The development of acid-stable water oxidation electrocatalysts is crucial for high-performance energy conversion devices. Different from traditional nanostructuring, here we employ an innovative microwave-mediated electron-phonon coupling technique to assemble specific Ru atomic patterns (instead of random Ru-particle depositions) on MnCrO surfaces (Ru-MnCrO) in RuCl solution because hydrated Ru-ion complexes can be uniformly activated to replace some Mn sites at nearby Cr-dopants through microwave-triggered energy coherent superposition with molecular rotations and collisions. This selective rearrangement in Ru-MnCrO with particular spin-differentiated polarizations can induce localized spin domain inversion from reversed to parallel direction, which makes Ru-MnCrO demonstrate a high current density of 1.
View Article and Find Full Text PDFACS Omega
January 2025
Department of Chemistry, Aarhus University, Langelandsgade 140, Aarhus C, Aarhus 8000, Denmark.
Pyruvic acid is an omnipresent compound in nature and is found both in the gas phase and in the particle phase of the atmosphere as well as in aqueous solution in the hydrosphere. Despite much literature on the photochemical degradation and stability of pyruvic acid in different chemical environments, the study of simultaneous interactions between gas-phase pyruvic acid or similar carboxylic acids with water and ions is not well-understood. Here, we present a study of microhydrated molecular clusters containing pyruvic acid and the structurally analogous carboxylic acids lactic acid, propionic acid, and 2,2-dihydroxypropanoic acid by probing geometries, binding free energies, hydrate distributions, as well as their infrared (IR) absorption spectra.
View Article and Find Full Text PDFACS Omega
January 2025
Faculty of Physics and Technology, Al-Farabi Kazakh National University, Al-Farabi ave. 71/23, 050040 Almaty, Kazakhstan.
This study investigates the formation of carbon dioxide clathrate hydrates under conditions simulating interstellar environments, a process of significant astrophysical and industrial relevance. Clathrate hydrates, where gas molecules are trapped within water ice cages, play an essential role in both carbon sequestration strategies and understanding of the behavior of ices in space. We employed a combination of Fourier Transform Infrared (FTIR) spectroscopy, mass spectrometry, temperature-programmed desorption (TPD), and Density Functional Theory (DFT) calculations to explore thin films of HO:CO ice mixtures with varying CO concentrations (5-75%) prepared by vapor deposition at temperatures ranging between 11 and 180 K.
View Article and Find Full Text PDFInt J Pharm
January 2025
School of Mechanical and Mechatronic Engineering, University of Technology Sydney (UTS), 15 Broadway, Ultimo, New South Wales 2007, Australia. Electronic address:
Nanocarrier-based dry powders for lung disease treatment are crucial, with in vitro and in silico research being pivotal to their success. This study introduces a method for creating Tiotropium-bromide liposomal inhalation dry powder, termed "Trojan-particles," utilizing thin-film hydration and spray-drying with lactose-arginine carriers. Encapsulating tiotropium-bromide in nanoliposomes enhances lung treatment via liposomes' unique features.
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
Laoshan Laboratory, Qingdao 266237, China.
Nucleation of multicomponent systems is a pervasive phenomenon in nature and is pertinent to a diverse array of scientific and industrial challenges. The nucleation mechanisms of immiscible multicomponent systems remain unclear. Here, gas hydrate is employed as a model system to study the nucleation of multicomponent systems.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!