From what I remember both the Japanese atomic bombings were air bursts in order to maximise the blast-related damage (see mach stem) and hence did not lead to any appreciable levels of fall-out. the Trinity test and the Nevada test site used many tower shots (~100 - 200ft off the ground) which...
An orifice plate is usually used to provide a sharp, localised pressure drop, which is usually accompanied by a degree of downstream pressure recovery. This makes them ideal for flow measuring devices (strictly you use them to measure the delta-P, pressure drop across the orifice plate). For...
When it comes to stopping high energy electromagnetic radiation there is little better than thickness and/or density - concrete and lead come to mind as suitable substances. Lead has the density but also produces high energy compton recoil electrons that can subsequently lose energy via...
If I recall correctly number density of a nuclide is just the number of atoms per unit volume as given by;
N = (Rho * NA) / A
Where; Rho = density (in g/cm^3)
NA = Avagadro number
A = Atomic weight in g
To find the composite for the mixture just weight by the...
I doesn't take infinity for the last bit of a quantity of a radioactive substance to decay. The process is a statistical one applicable to large numbers of particles and won't hold when you are right down there at small numbers. I think you are taking the mathematical formalism of radioactive...
Hi Hamster
Thanks for the reply. I think what you have is more or less consistent with the expression I stated. The value you quote for alpha looks to be the fine structure constant, which is defined in textbooks as
e^2/(hbar*c)
where c = speed of light
trouble is with SI units...
Hello
I am re-reading some of my old textbooks and have come across a simplified (non-relativistic) term used to correct the beta decay spectrum for the coulomb effect of the nucleus on the ejected beta particle. The expression is;
F(Z,E) = (2*Pi*n) / (1 - exp(-2*Pi*n))
where n =...
That sounds about right to me. Cube and sphere geometry are the easiest to solve (the flux shapes in the cube reactor are simple cosines in each direction). I'm not sure how important the point source is in the determination of the parameters of a critical system.
Who throws radioactive waste out at sea? High level waste (fission products recovered from spent fuel) tends to be stored dissolved in nitric acid in cooled stainless steel tanks. There are liquid effluent discharges but these tend to make up a small minority of the total radioactive inventory...
You wash! It's not that uncommon if you work at a 40 year old Nuclear utility like I do. Detection capability is very sensitive these days. Plutonium contamination has to be treated with care as you wouldn't want to break the skin and allow internal contamination.
PS You never seen the...
I've been a professional in the Nuclear power field for 21 years and "Nuclear Reactor Analysis" by Duderstadt & Hamilton is advanced a textbook as you need. After that you are doing your own research or relying on the specialised work of others (usually those within your own organisation)