XCV. Energy expenditure per ion pair for electrons and α-particles

The energy expenditure per ion pair, V , for electrons in argon, helium, hydrogen, nitrogen, air, oxygen and methane is determined using ion chambers and proportional counters with terminals which correct for ‘end-effect’. Experiments using 37 A and tritium as sources of ionizing electrons are performed. Curves of ion current against percentage of argon admixed with the other gases are plotted. The variation of V with energy of the ionizing electrons is investigated for nitrogen between the limits 200 eV and 46*7 keV for the primary electrons and only a small variation is found. The ratio V gas/ V argon is given in each case and is found to be almost identical to the corresponding ratio for ionization by 340 MeV protons. Examination of previous work with α- particles suggests close agreement with the values for electrons and protons.

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Average energy expenditure per ion pair in gases and gas mixtures

Reports on Progress in Physics ◽

10.1088/0034-4885/21/1/301 ◽

1958 ◽

Vol 21 (1) ◽

pp. 1-29 ◽

Cited By ~ 65

Author(s):

J M Valentine ◽

S C Curran

Keyword(s):

Energy Expenditure ◽

Average Energy ◽

Gas Mixtures ◽

Ion Pair ◽

Average Energy Expenditure

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Average Energy Expenditure per Ion Pair for 0$middot$8 MeV Carbon and Nitrogen Recoils

Physics in Medicine and Biology ◽

10.1088/0031-9155/12/3/304 ◽

1967 ◽

Vol 12 (3) ◽

pp. 321-331 ◽

Cited By ~ 6

Author(s):

Bridget J Carter

Keyword(s):

Energy Expenditure ◽

Average Energy ◽

Ion Pair ◽

Carbon And Nitrogen ◽

Average Energy Expenditure

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XLVII. Investigation of soft radiations.—VII. Energy expenditure per ion-pair for slow electrons in various gases

The London Edinburgh and Dublin Philosophical Magazine and Journal of Science ◽

10.1080/14786445008561116 ◽

1950 ◽

Vol 41 (317) ◽

pp. 517-524 ◽

Cited By ~ 11

Author(s):

S.C. Curran ◽

A.L. Cockroft ◽

G.M. Insch

Keyword(s):

Energy Expenditure ◽

Ion Pair ◽

Slow Electrons

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Calculation of the energy per ion pair for α -particles in helium

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1954.0164 ◽

1954 ◽

Vol 224 (1158) ◽

pp. 362-373 ◽

Cited By ~ 29

Keyword(s):

Integral Equation ◽

Energy Range ◽

Born Approximation ◽

Ion Pairs ◽

Average Energy ◽

Ion Pair ◽

Α Particles

The average energy per ion pair, W , for the ionization of helium by 1 to 6 MeV α -particles is calculated using the Born approximation, the number of ion pairs produced by secondary, tertiary, etc., electrons being calculated from an integral equation which is solved numerically. The calculated W is nearly constant over this energy range, with average W = 41∙1 eV. This agrees well with the value, W = 42∙7 eV, measured recently by Jesse & Sadauskis for 5∙3 MeV α -particles in helium, and supports their suggestion that the earlier measured values of W for α -particles in helium may have been spuriously low owing to the presence of small amounts of other gases.

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Alignment of small He-Bubbles during in situ deformation of Al-foils

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109124 ◽

1978 ◽

Vol 36 (1) ◽

pp. 396-397

Author(s):

E. Ruedl ◽

P. Schiller

Keyword(s):

Fusion Reactor ◽

Matrix Material ◽

Fusion Reactors ◽

First Wall ◽

Potential Matrix ◽

In Situ Deformation ◽

Α Particles ◽

Metal Aluminium

The low Z metal aluminium is a potential matrix material for the first wall in fusion reactors. A drawback in the application of A1 is the rel= atively high amount of He produced in it under fusion reactor conditions. Knowledge about the behaviour of He during irradiation and deformation in Al, especially near the surface, is therefore important.Using the TEM we have studied Al disks of 3 mm diameter and 0.2 mm thickness, which were perforated at the centre by double jet polishing. These disks were bombarded at∽200°C to various doses with α-particles, impinging at any angle and energy up to 1.5 MeV at both surfaces. The details of the irradiations are described in Ref.1. Subsequent observation indicated that in such specimens uniformly distributed He-bubbles are formed near the surface in a layer several μm thick (Fig.1).After bombardment the disks were deformed at 20°C during observation by means of a tensile device in a Philips EM 300 microscope.

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A compendium of G-protein–coupled receptors and cyclic nucleotide regulation of adipose tissue metabolism and energy expenditure

Clinical Science ◽

10.1042/cs20190579 ◽

2020 ◽

Vol 134 (5) ◽

pp. 473-512 ◽

Cited By ~ 5

Author(s):

Ryan P. Ceddia ◽

Sheila Collins

Keyword(s):

Adipose Tissue ◽

Energy Expenditure ◽

Signaling Pathways ◽

G Protein ◽

Uncoupling Protein ◽

Beige Adipocytes ◽

Nucleotide Regulation ◽

Ucp1 Expression ◽

Thermogenic Adipocytes ◽

G Protein Coupled

Abstract With the ever-increasing burden of obesity and Type 2 diabetes, it is generally acknowledged that there remains a need for developing new therapeutics. One potential mechanism to combat obesity is to raise energy expenditure via increasing the amount of uncoupled respiration from the mitochondria-rich brown and beige adipocytes. With the recent appreciation of thermogenic adipocytes in humans, much effort is being made to elucidate the signaling pathways that regulate the browning of adipose tissue. In this review, we focus on the ligand–receptor signaling pathways that influence the cyclic nucleotides, cAMP and cGMP, in adipocytes. We chose to focus on G-protein–coupled receptor (GPCR), guanylyl cyclase and phosphodiesterase regulation of adipocytes because they are the targets of a large proportion of all currently available therapeutics. Furthermore, there is a large overlap in their signaling pathways, as signaling events that raise cAMP or cGMP generally increase adipocyte lipolysis and cause changes that are commonly referred to as browning: increasing mitochondrial biogenesis, uncoupling protein 1 (UCP1) expression and respiration.

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