Results 11 to 20 of about 174,760 (197)
The ionization of helium by neutral helium atoms [PDF]
Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1946 A method is described for investigating the ionization produced in helium by collisions between quasi-stationary atoms—that is, atoms possessing only therm al velocities—and a beam of neutral helium atoms with kinetic energy less than 100 eV. Ionization is shown to begin when the kinetic energy of the bombarding atoms is twice as great as the minimum ...
F, HORTON, D M, MILLEST
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Monte Carlo simulation of positronium thermalization in gases [PDF]
Hemijska Industrija, 2010 In this paper we present the results of Monte Carlo simulations of positronium (Ps) swarm thermalization in helium (He) and water vapour. We have investigated the temporal evolution of energy and spatial parameters of the swarm and their sensitivity to ...
Marjanović Srđan D., Šuvakov Milovan
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Adsorption of Helium and Hydrogen on Triphenylene and 1,3,5-Triphenylbenzene
Molecules, 2022 The adsorption of helium or hydrogen on cationic triphenylene (TPL, C18H12), a planar polycyclic aromatic hydrocarbon (PAH) molecule, and of helium on cationic 1,3,5-triphenylbenzene (TPB, C24H18), a propeller-shaped PAH, is studied by a combination of ...
Stefan Bergmeister +6 more
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Proceedings of the National Academy of Sciences, 1998 The ratio 3 He/ 4 He (R) plays a central role in models of mantle evolution that propose an undegassed lower mantle, rich in the primordial isotope 3 He. A large primordial volatile-rich reservoir, a feature of recent models, is inconsistent with high-temperature ...
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Argon–Helium Cryoablation for Cutaneous Squamous Cell Carcinoma in the Elderly
Frontiers in Oncology, 2022 Cutaneous squamous cell carcinoma (cSCC) is a common type of malignant neoplasm in non-melanoma skin cancer (NMSC). Most cases of simple cSCC are considered curable by surgical removal of the lesion.
Qianwen Huang, Wenshen Xu
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Study on the Effect of Helium on the Dielectric Strength of Medium-Voltage Vacuum Interrupters
Energies, 2021 This paper presents the results of a comparative analysis of the dielectric strength of disconnecting vacuum interrupters operating on air and helium. The breakdown voltage Ud was measured in the pressure range from 8.0 × 10−4 Pa to 3.0 × 101 Pa for air ...
Paweł Węgierek +3 more
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The Cosmic Production of Helium [PDF]
Science, 2003 We estimate the cosmic production rate of helium relative to metals (Δ Y/ Δ Z ) using K dwarf stars in the Hipparcos catalog with accurate spectroscopic metallicities. The best fitting value is Δ Y/ Δ Z = 2.1 ± 0.4 at the 68% confidence level ...
Jimenez, Raul +3 more
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WHY WE CANNOT PREDICT STRONG EARTHQUAKES IN THE EARTH’S CRUST
Геодинамика и тектонофизика, 2015 In the past decade, earthquake disasters caused multiple fatalities and significant economic losses and challenged the modern civilization. The wellknown achievements and growing power of civilization are backstrapped when facing the Nature. The question
Iosif L. Gufeld +2 more
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AerospaceLunar dust remains one of the most critical unresolved challenges to long-duration lunar missions. Its sharp, abrasive, and electrostatically charged particles are easily inhaled and can penetrate deep into the lungs, reaching the bloodstream and the ...
Christopher Salvino +9 more
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High Voltage, 2016 Cold atmospheric-pressure He + N(2) and He + O(2) plasmas are chosen as the representatives for electropositive and electronegative plasmas, of which the discharge characteristics are studied and then compared to each other by fluid models.
Ding Xin Liu +5 more
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