Basic

Nuclear Power – Converting Mass Into Energy?

One of the things that most people know about nuclear power is that it about turning mass into energy – E= mc2. Although this is not wrong it is extremely misleading. First of all I am going to digress a bit. One of the things that makes Einsteins theory of relativity important is that it […]

Share

Posted in Basic | No Comments »

Radioactivity of U-238

This is just an example of how to calculate the radioactivity of an isotope from its halflife. Uranium 238 has a halflife of 4.468×109 years (4,468,000,000years). This is 4.468×109 x 365.25 x 24 x 60 x 60 = 1.41×1017 seconds. We can now calculate the decay constant (i.e. the number of decays per second) using […]

Share

Posted in Basic | No Comments »

Implications of High Burnup Fuel – Basic Notes

An important issue around nuclear new build is the amount and what happens to the spent fuel. The proposed EPR reactors at Sizewell and Hinkley are designed to run oh ‘high burnup’ fuel. This post has a basic look at what the implications are. This is a rough wordy explanation and I hope to be […]

Share

Posted in Basic, Spent Fuel | No Comments »

Spent Fuel – Basic Notes

These are just a few basic notes about spent fuel waste from nuclear power stations. It assumes a basic understanding of the nuclear fission process (see Basic Nuclear Physics workshop), however, I have tried to provide links to the relevant sections within this blog. This post is designed as a basic introduction for the discussion […]

Share

Posted in Basic, Spent Fuel | No Comments »

Nuclear Fusion

Let us look at the graph for the energy of various nuclei. Remember tht this graph is upside down and so Iron (Fe) has the lowest energy. We have seen when talking about alpha decay that some elements with atomic number higher than that of iron can decrease their mass by emitting an alpha particle […]

Share

Tags:

Posted in Basic | No Comments »

About Uranium

It would be useful at this point to talk a bit more about Uranium and its isotopes. Uranium naturally occurs as two isotopes details of which are shown below. Atomic Mass Halflife Occurance 238 4.5×109years 99.3% 235 7×108 years 0.7% Of the two isotopes only Uranium-235 is fissile. However some of the Uranium-238 is converted […]

Share

Tags: , ,

Posted in Basic | No Comments »

The Rate of Decay

The rate at which these unstable isotopes undergo decay varies greatly between the different isotopes. The process is random for each atom. However there is a fixed probability that an atom will disintegrate over a fixed time scale. It is rather like throwing a dice – on an individual throw then you cannot be certain […]

Share

Tags: ,

Posted in Basic | No Comments »

Gamma Radiation

When an atom undergoes alpha or beta decay it can leave the nucleus in a high energy state. The atom goes to a lower energy state by emitting light. This light is very high energy (high frequency – short wavelength) and is called gamma (γ) radiation. The nucleus stays the same i.e. its atomic mass […]

Share

Tags:

Posted in Basic | No Comments »

Decay Chains

When an atom undergoes radioactive decay the isotope produced is not necessarily stable itself. If it is not then that can undergo radioactive decay. This can carry on in what are called decay chains. In the diagram above the atomic mass is along the bottom (204-240) and the atomic number up the side. Starting with […]

Share

Tags:

Posted in Basic | No Comments »

Moderation

We have discussed fission and neutron capture. Now we are going to talk about how we can increase the likelihood that fission or neutron capture happening. What happens depends on the energy (speed) of the neutrons. The neutron induced fission process is much more likely to happen if the neutrons have a lower energy than […]

Share

Tags:

Posted in Basic | No Comments »

Subscribe