For a general overview about nuclear physics, engineering, and power plants refer to the following documents prepared by the U.S. Nuclear Regulatory Commission (NRC):
Nuclear Power for Electrical Generation
Boiling Water Reactor (BWR) Systems
Pressurized Water Reactor (PWR) Systems
Natural and Man-Made Source of Radiation
Radiation Sources at Nuclear Power Plants
Biological Effects of Radiation
Transportation of Radioactive Materials
Spent Nuclear Fuel Pool Design Basis per the NRC
Background information about radiation and what it does pdf1
by Dr. Jacquelyn Yanch
Comments on the radiation levels resulting from the damaged nuclear power plants in Fukushima and the impact of these levels on human health. pdf2
by Dr. Jacquelyn Yanch
Radiation in their future: Dealing with the contaminated environment in Japan pdf3
by Dr. Jacquelyn Yanch
A Macedonian translation of the “What is an Isotope” post is available at http://webhostinggeeks.com/science/mitnse-what-mk