Helium Absorption at 1083 nm from Extended Exoplanet Atmospheres: Dependence on Stellar Radiation [PDF]
ApJ, 881, 133 (2019), 2019 Strong absorption signatures in the helium line at 1083 nm have recently been detected in transmission spectra of several close-in exoplanets. This absorption line originates from neutral helium atoms in an excited, metastable 2$^3$S state. The population of helium atoms in this excited state is governed by the spectral shape and intensity of the ...
A. Oklopčić
arxiv +3 more sources
The Solidification of Helium [PDF]
Nature, 1908 IN the telegram from Prof. Kamerlingh Onnes announcing the solidification of helium, the statement is made that “the last evaporating parts show considerable vapour pressures as if liquid state is jumped over”—in other words, it apparently sublimes.
Alfred W. Porter
openalex +4 more sources
Review of Membranes for Helium Separation and Purification
Membranes, 2017 Membrane gas separation has potential for the recovery and purification of helium, because the majority of membranes have selectivity for helium. This review reports on the current state of the research and patent literature for membranes undertaking ...
Colin A. Scholes, Ujjal K. Ghosh
doaj +2 more sources
Re‐evaluation of argon (E 938) and helium (E 939) as food additives [PDF]
EFSA JournalThe Panel on Food Additives and Flavourings (FAF) provides a scientific opinion re‐evaluating the safety of the two food additives argon (E 938) and helium (E 939). Argon (Ar) and helium (He) are two noble gases, highly stable single atoms.
EFSA FAF Panel (EFSA Panel on Food Additives and Flavourings) +21 more
doaj +2 more sources
Adsorption behavior of helium in quartz slit by molecular simulation [PDF]
Scientific ReportsDue to the multiple influences of unique physicochemical properties of helium, petrographic characteristics and temperature and pressure conditions, little is known about the helium adsorption behaviors in minerals and rocks at geological conditions ...
Bing You +5 more
doaj +2 more sources
The PHLEK Survey: A New Determination of the Primordial Helium Abundance [PDF]
Astrophysical Journal, 2020 We present Keck NIRSPEC and Keck NIRES spectroscopy of sixteen metal-poor galaxies that have pre-existing optical observations. The near-infrared (NIR) spectroscopy specifically targets the He i λ10830 Å emission line, due to its sensitivity to the ...
Tiffany Hsyu +3 more
semanticscholar +1 more source
Therapeutic gases used in balneotherapy and rehabilitation medicine - scientific relevance in the last ten years (2011 – 2020) - Synthetic literature review [PDF]
Balneo and PRM Research Journal, 2021 : Background. The medical relevance of therapeutic gases can range from use in burns and stroke victims to hypoxia therapy in children. However, medical gases such as oxygen, hydrogen, helium and xenon have recently come under increased exploration for
MUNTEANU Constantin +3 more
doaj +1 more source
Improving helium abundance determinations with Leo P as a case study [PDF]
Journal of Cosmology and Astroparticle Physics, 2020 Currently, the primordial helium abundance is best estimated through spectroscopic observations of H II regions in metal-poor galaxies. However these determinations are limited by several systematic uncertainties which ultimately limit our ability to ...
E. Aver +5 more
semanticscholar +1 more source
Assessing the expansion of the Cambrian Agronomic Revolution into fan-delta environments
Scientific Reports, 2022 The intensity, extent, and ecosystem-level impact of bioturbation (i.e. Agronomic Revolution) at the dawn of the Phanerozoic is a hotly debated issue.
Andrei Ichaso +4 more
doaj +1 more source
Unimpeded Permeation of Water Through Helium-Leak–Tight Graphene-Based Membranes [PDF]
Science, 2011 Porous Membranes Thin semi-permeable membranes are commonly used as chemical barriers or for filtration purposes. While the size of the pores will influence which molecules are able to pass, other factors—including the surface chemistry of the pore walls,
R. Nair +4 more
semanticscholar +1 more source