We present a review on the determination of the primordial helium abundance, Y_p, based on the study of hydrogen and helium recombination lines in extragal... M Peimbert,V Luridiana,A Peimbert,... - From Stars to Galaxies: Building the Pieces to Build Up the Universe 被引量: 14发表: ...
AN excited state of helium of mass 3 (He) has been previously suggested by me to explain a second low-energy group of neutrons from the deuteron-deuterium reaction. Since present theory does not predict such an excited statein He, it is important to establish definitely whether such a state...
The total mass of helium in a balloon is 114 kg. What is the volume of the balloon? Volume: The volume of an object is the total space it occupies due to its mass content. The volume is measured in the units of meter cubed. The volume depends on the densit...
The mass of a (poly)peptide in proteomics is described by its monoisotopic mass, average mass or nominal mass in atomic mass units (u or amu), which is called the Dalton (Da). The monoisotopic mass of an ion is calculated using the ‘exact’ mass of the predominant isotope of each ...
A star expands to become a red giant when it has fused all the hydrogen in its core into helium. If the star is in a binary system, its envelope can overflow onto its companion or be ejected into space, leaving a hot core and potentially forming a subdwa
The coupled-mode equations for systems of four and five planar coupled waveguides are investigated to determine transmission characteristics of interest. By proper selection of the coupling coefficients in a system of "synchronous" waveguides, full transfer can be achieved from one outermost guide to ...
4 A helium balloon is tied to a top-pan balance. A metal block of mass 100g is placed on the balance. The reading on the balance is 91g. D helium balloon metal block91g8o Which statement can be deduced from this experiment? A The balloon exerts a downward force of 0.09 N on the...
Cold masses - carrier structure and helium vessel of actively shielded open mri - magnet high field strength An open magnetic resonance - imaging (mri) - device 100 with at least one main coil 110, 115 for generating a magnetic field for imaging of a volume and at... THOMPSON, PAUL S....
Technical specification applicable to liquid sodium service component/system of Fast Breeder Reactors envisage reliable sensitivity for detection of the minutest leaks of the order of 1 × 1010 Pa.m3/s with the help of a mass spectrometer helium leak detector. However, it is difficult to achieve ...
Mass Spectrometers, Helium Leak Detectors, and Residual Gas Analyzers Charles A. Bishop, in Vacuum Deposition Onto Webs, Films and Foils (Third Edition), 2015 The performance of systems will decline with time due to absorbed moisture, a change in internal surface area due to stray deposition bei...