An Atomic Future

Through the radio and the public press we have all been made keenly aware of the extremely destructive power of nuclear energy. The devastating effects of a nuclear explosion have been graphically depicted in terms of miles of influence, millions of dollars, months of time and multitudes of human lives

Tensile test to find endurance limit of strain-ageable metals

Fatigue curves for steel C-1118 were constructed for room temperature and 100° C from data collected from a number of fatigue tests. The endurance limit of the steel was estimated at the same temperatures from additional fatigue tests

Temperature distribution in a metal cylinder containing a heat source

The object of this reportt is to describe a method for finding the temperature distribution in a metal cylinder containing a heat source distributed in any manner throughout the cylinder. Specific solutions are given for cylinders with L/D ratios of 1, 2, 3, and ∞.

Halo gas cross sections and covering fractions of MgII absorption selected galaxies

We examine halo gas cross sections and covering fractions, fc, of intermediate-redshift Mg II absorption selected galaxies. We computed statistical absorber halo radii, Rx, using current values of dN/dz and Schechter luminosity function parameters, and have compared these values to the distribution of impact parameters and luminosities from a sample of 37 galaxies. For equivalent widths Wr(2796) ≥ 0.3 Å, we find 43 ≤ Rx ≤ 88 kpc, depending on the lower luminosity cutoff and the slope, β, of the Holmberg-like luminosity scaling, R ∝ α L^β . The observed distribution of impact parameters, D, are such that several absorbing galaxies lie at D > Rx and several non-absorbing galaxies lie at D ~ 0.5 for our sample. Moreover, the data suggest that halo radii of Mg II absorbing galaxies do not follow a luminosity scaling with β in the range of 0.2–0.28, if fc = 1 as previously reported. However, provided fc ~ 0.5, we find that halo radii can remain consistent with a Holmberg-like luminosity relation with β ≃ 0.2 and R∗ = Rx/√(fc) ~ 110 kpc. No luminosity scaling (β = 0) is also consistent with the observed distribution of impact parameters if fc ≤ 0.37. The data support a scenario in which gaseous halos are patchy and likely have non-symmetric geometric distributions about the galaxies. We suggest that halo gas distributions may not be governed primarily by galaxy mass/luminosity but also by stochastic processes local to the galaxy

The stress-strain characteristics of uranium

Tests were made in reversed loading and in repeated tensile loading on thirteen specimens of rolled, alpha-uranium at room temperature. Constant strain rates ranging from 0.0003 in./in./min. to 0.0060 in./in./min. were employed

Observation on creep of tantalum

Because of its high melting point (2976C) tantalum has received consideration as a structural material in nuclear reactors which operate at high temperatures. Corrosion and erosion studies of tantalum in a hot loop have been carried out using a bismuth-uranium alloy as the circulating fuel-coolant, but comparatively little information is available on the mechanical properties of tantalum, particularly on the creep resistance at high temperatures. Therefore, a program of determining some of these properties was undertaken by Nuclear Engineering Group I, and preliminary studies of the creep behavior of tantalum are reported herein

Ratio of solid velocity to mixture velocity in slurry flow

The study consisted of two parts, a theoretical analysis of the problem and an experimental investigation under controlled conditions. The theoretical analysis resulted in an equation which expressed the velocity ratio in terms of dimensionless parameters representing the distribution of the particles in the mixture, the slip between the solid particles and the adjacent fluid, and the velocity distribution of the fluid in the conduit

Influence of rate of loading on the tensile properties of normal alpha uranium

Forty t ensile tests were carried out on normal alpha uranium in order to determine the influence of the rate of loading and temperature on its tensile properties . These tests were conducted at eleven different temperatures in the temperature range from 25 1to 600°C for three constant loading rates (0 . 0017 min -l, 0 . 0130 min- , and 0. 0400 min -1) . The properties considered were tensile strength, per cent elongation (in 1. 5 in. gage length), percentage reduction in area, yield strength, and modulus of elasticity. All of these properties were more strongly affected by a change in temperature than they were by a change in rate of loading. Graphs showing data for each of the five properties vs temperature and also as a function of rate of loading are ·displayed to indicate specific effects. Original stress-strain curves included along with graphs indicating the slopes of each of these. curves (subsequent to the initial elastic strain portion) as a function of temperature and rate of loading