Measurements of the electrical conductivity profile in the detonation front of solid explosives

1974 ◽  
Vol 10 (6) ◽  
pp. 776-782 ◽  
Author(s):  
A. P. Ershov ◽  
P. I. Zubkov ◽  
L. A. Luk'yanchikov
2019 ◽  
Vol 206 ◽  
pp. 249-251 ◽  
Author(s):  
Nataliya P. Satonkina ◽  
Alexander P. Ershov ◽  
Andrey V. Plastinin ◽  
Alexander S. Yunoshev

Soil Research ◽  
1981 ◽  
Vol 19 (3) ◽  
pp. 197 ◽  
Author(s):  
JA Mullins

The plant available water capacity (PAWC) was measured for a range of soils (black earths, grey, brown and red clays, krainozems, yellow earths and solodized solonetz/solodics) used for dryland agriculture in the uplands of th,- eastern Darling Downs of Queensland. Using these data, two one-parameter models - one based on the electrical conductivity profile and the other on observable profile features - were derived for estimating the PAWC of the soil profile. The electrical conductivity profile model reliably estimated the PAWC for black earths and grey, brown and red clays. In the case of the deep, black earths, it accounted for 90% of the variation. The observable profile feature model reliably estimated the PAWC for black earths and grey, brown and red clays and in the case of the grey, brown and red clays accounted for 88% of the variation. The models for the solodized solonetz/solodics were not significant. In addition the profile feature model provided estimates of PAWC for the krasnozems (grouped with black earths) and for the yellow earths and solodized solonetz/solodics as a group. An alternative technique for the estimation of PAWC for krasnozems and yellow earths is also presented. The techniques will provide a rapid first appraisal of the PAWC of a soil profile.


Detonation processes have been observed in narrow, heavily confined, columns of solid explosive by a new microwave interferometric technique. The technique is described and a multiple-beam theory of fringe shape is given. The location, with respect to the detonation front, of the surface reflecting the microwaves is discussed. Detonation velocity as a function of distance along the column is derived from an oscilloscope display of the fringe pattern. The calculation of the detonation velocity requires a knowledge of the wavelength of the microwaves in the explosive. For this purpose the relative permittivities of a number of explosives are given as a function of their pressed density. The accuracy and applications of the method are discussed. Experiments on tetryl are described in which the technique is evaluated by observing the detonation velocity for a range of densities, and is applied to resolution of the velocity transient during growth to detonation. A simple theory of growth is used to estimate the reaction zone length (0.4 mm) and the activation energy (2 kcal/mole) in the detonation of tetryl.


Nature ◽  
1971 ◽  
Vol 232 (5308) ◽  
pp. 249-251 ◽  
Author(s):  
A. F. KUCKES

2014 ◽  
Vol 123 (4) ◽  
pp. 827-835 ◽  
Author(s):  
Daniel N Obiora ◽  
Francisca N Okeke ◽  
K Yumoto ◽  
Stan O Agha

2020 ◽  
Vol 498 (1) ◽  
pp. 621-638
Author(s):  
Deniz Soyuer ◽  
François Soubiran ◽  
Ravit Helled

ABSTRACT Determining the depth of atmospheric winds in the outer planets of the Solar system is a key topic in planetary science. We provide constraints on these depths in Uranus and Neptune via the total induced Ohmic dissipation, due to the interaction of the zonal flows and the planetary magnetic fields. An upper bound can be placed on the induced dissipation via energy and entropy flux throughout the interior. The induced Ohmic dissipation is directly linked to the electrical conductivity profile of the materials involved in the flow. We present a method for calculating electrical conductivity profiles of ionically conducting hydrogen–helium–water mixtures under planetary conditions, using results from ab initio simulations. We apply this prescription on several ice giant interior structure models available in the literature, where all the heavy elements are represented by water. According to the energy (entropy) flux budget, the maximum penetration depth for Uranus lies above 0.93 RU (0.90 RU) and for Neptune above 0.95 RN (0.92 RN). These results for the penetration depths are upper bounds and are consistent with previous estimates based on the contribution of the zonal winds to the gravity field. As expected, interior structure models with higher water abundance in the outer regions also have a higher electrical conductivity and therefore reach the Ohmic limit at shallower regions. Thus, our study shows that the likelihood of deep-seated winds on Uranus and Neptune drops significantly with the presence of water in the outer layers.


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