Radioactive Decay Calculation Applet

This is a tool that we developed as part of a database-driven application for a pharmaceutical company (Radioactive Materials Supply Management). The applet reads information (element, nuclide number, half life) from a simple textfile (Nuclides.txt - in the real application the information comes from a database). Then the following calculations can be performed:

• Activity at a certain date (whether in the future or in the past)
• Date at which a certain activity will be (or was) reached

To perform an activity calculation, choose a nuclide, the activity, and the start and ending date. You can also use this to find out what the activity was in the past, e.g. when the sample entered the company.

To perform a calculation of a date at which a certain activity is (or was) reached, use the "Date Calculation" radiobutton. You can then enter a value for the required activiy. You can also use this to find out at which date in the passed the activity was present.

Activities can only have numeric values (try to enter something else and see how it is simply ignored !).

This applet requires you to have the Java-2 plugin installed. If this is not the case, the browser should simply ask you to download and install it from the Sun Microsystems Java website. If you do not have the Java-2 plugin installed, and your browser does not install it automatically, go to the Sun website, go to the "Download Production Release 1.3" section and install the Java-2 plugin following the instructions.
The Java-2 plugin is just a plugin like the Flash-plugin and other plugins you already have. It is perfectly safe and especially useful for intranets.

This tool was designed, constructed, tested and deployed in just somewhat more than 2 working days. It shows how efficiently intranet tools can be developed (we are however specialists in Chemistry and in Java !), using reusable compounds (we have a whole library of them).

Download

You need to download the following components, and install them in the same directory

• The basic HTML file
• The DecayApplet.jar file
• The JNumberField reusable compound (also see our other goodies)
• The Calendar Bean, a reusable compound created by Kai Tödter

Comments

• This kind of tools is very useful on (fast) intranets. Java2 enables to develop fast (it is object oriented), leading to robust applications (Java2 is much safer than C++), which can be deployed on the intranet (the user only needs a browser).
• If you look at the source code of this HTML file, you will see that in the tag describing the Java-2 plugin (the <OBJECT> tag), a reference is made to the web side from where the Java-2 plugin can be loaded and installed. On an intranet of course, you would replace this reference by the one that directs to the place on your intranet from where the plugin can be installed.

A few other applets and applications found on internet (there are many more ...):

• Natural RadioActive Series (by Yevgeniy Miretskiy): demonstrates natural decay of Th-232, Pu-241, U-238 and U-235.
• A decay calculator from ConvertALot.com
  Same functionality as ours, but not so nice and much less versatile.
• jvNUbase: A visual, clickabal map of all nuclides in the universe, gives valuable information on each of the nuclides
• The Law of Radioactive Decay: an illustrative applet (by Walter Fendt) demonstrating the decay of nuclides: interesting for teaching.
• Another decay calculator from the University of Illinois
• Time evolution of a radioactive sample: another demo to show the concept of radioactive decay. From Merlot Multimedia Educational Resource
• Another table (database) of nuclides. Much information. By Jonghwa Chong.
• Chart of Nuclides. From Jun-ichi Katakura.
• Tables of Nuclides. Very easy-to-use interactive table of nuclides. Click an element and you get all the nuclides. From the Nuclear Data Center
• RadioActivity Unit Converter. Very useful. Curie to Bequerel conversions and vice versa. From the Department of Environmental Health and Safety.

other goodies