We report measurements of the statistical vibrational autodetachment (VAD, also called thermionic emission) and radiative cooling rates of isolated -benzoquinone (BQ, CHO) radical anions using the cryogenic electrostatic ion storage ring facility DESIREE. The results are interpreted using master equation simulations with rate coefficients calculated using statistical detailed balance theory. The VAD rate is determined by measuring the time-dependent yield of neutral BQ due to spontaneous electron emission from a highly-excited ensemble of anions formed in an electron-attachment ion source. Competition with radiative cooling quenches the VAD rate after a critical time of = 11.00(5) ms. Master equation simulations which reproduce the VAD yield provide an estimate of the initial effective vibrational temperature of the ions of 1100(20) K, and provide insight into the anion formation scenario. A second measurement of the radiative cooling rate of BQ stored for up to 0.5 s was achieved using time-dependent photodetachment action spectroscopy across the A ← B and B ← B transitions. The rate at which hot-band contributions fade from the action spectrum is quantified by non-negative matrix factorisation. This is found to be commensurate with the average vibrational energy extracted from the simulations, with 1/ lifetimes of 0.16(3) s and 0.1602(7) s, respectively. Implications for astrochemistry are discussed.
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Proc Natl Acad Sci U S A
January 2025
Archaeology & Palaeoecology, School of Natural and Built Environment, Queen's University, Belfast BT9 3AZ, United Kingdom.
Polar ice cores and historical records evidence a large-magnitude volcanic eruption in 1831 CE. This event was estimated to have injected ~13 Tg of sulfur (S) into the stratosphere which produced various atmospheric optical phenomena and led to Northern Hemisphere climate cooling of ~1 °C. The source of this volcanic event remains enigmatic, though one hypothesis has linked it to a modest phreatomagmatic eruption of Ferdinandea in the Strait of Sicily, which may have emitted additional S through magma-crust interactions with evaporite rocks.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, 999077, China.
Traditional window glazing, with inherently adverse energy-efficient optical properties, leads to colossal energy losses. Energy-saving glass requires a customized optical design for different climate zones. Compared with the widely researched radiative cooling technology which is preferable to be used in low-altitude hot regions; conversely in high-latitude cold regions, high solar transmittance (T) and low mid-infrared thermal emissivity (ε) are the key characteristics of high-performance radiative warming window glass, while the current low-emissivity (low-e) glass is far from ideal.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Mechanical Engineering, Tianjin University of Commerce, Tianjin 300134, PR China. Electronic address:
To this day, energy conservation, emission reduction, and environmental protection continue to be goals pursued by humanity. Passive radiation cooling, as a zero-consumption refrigeration technology, offers substantial opportunities for reducing global energy consumption and carbon dioxide emissions. It is of great significance to develop high-performance passive radiation cooling materials from sustainable materials.
View Article and Find Full Text PDFElectromagn Biol Med
January 2025
Department of Applied Mathematics, University of Calcutta, Kolkata, India.
The current investigation explores tri-hybrid mediated blood flow through a ciliary annular model, designed to emulate an endoscopic environment. The human circulatory system, driven by the metachronal ciliary waves, is examined in this study to understand how ternary nanoparticles influence wave-like flow dynamics in the presence of interfacial nanolayers. We also analyze the effect of an induced magnetic field on Ag-Cu-/blood flow within the annulus, focusing on thermal radiation, heat sources, buoyancy forces and ciliary motion.
View Article and Find Full Text PDFSmall
January 2025
School of Mechanical Engineering, Korea University, 145 Anam-Ro, Seongbuk-Gu, Seoul, 02841, Republic of Korea.
Passive temperature controls like passive daytime radiative cooling (PDRC)-heating (PDRH), and thermal insulation are essential to meet the growing demand for energy-efficient thermal solutions. When combined with advanced functions like electromagnetic interference shielding, these technologies can significantly enhance scalability. However, existing approaches using single thin films or uniform porous materials face inherent limitations in optimizing versatile functions, while lightweight, insulating aerogels can extend their multifunctionality by manipulating pores and fillers.
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