not only fissible, but feasible too!!!
sir i m 2nd yr student i need sum fissible , innovative and simple project for my current academic yr......plzz help me out over dis ....i need all possible help
you need something "fissible"?
you're in luck, i studied some nuclear chemistry and can give you a few pointers. Here goes:
Very few elements are easily "fissible", that is, capable of undergoing nuclear fission reactions under accessible conditions. While in theory anything can fission (even helium) when injected with enough energy, in practice, only extremely heavy elements (particular the radioactive ones) can be made to fission.
If you want to build a demonstration fission device then first you need a few materials. Most of these can actually be obtained by the average person without running afoul of nuclear regulatory agencies.
The most easily "accessible" fissible material is Uranium-233. This is a highly radioactive form of uranium. Naturally occuring uranium is mostly Uranium-238, this uranium is abundant but is not fissible under "accessible" conditions. It will however fission using extremely fast neutrons found in nuclear explosions.... however a nuclear bomb is not "accessible" to the average person and thus you shouldn't try this. Uranium-238 can be converted to Plutonium-239 which is fissible. But Plutonium-239 is highly toxic and thus i strongly reccomend you stay away from this method.
Uranium-235 is fissible under accessible conditions BUT only makes up 0.73% of natural uranium. While you may be able to get a hunk of natural uranium and get the Uranium-235 to fissile, the radiation products would not be easily detectable against background. Pretty hard then to prove to your professor you actually did things properly if you can't measure the results.
Americans and russians used enriched uranium reactors where the concentration of uranium-235 is raised to 3%. Iran and a few other countries are currently pursuing this method power generation and is currently causing international unrest since this method can also be used to make nuclear bombs.
Canadians designed and built something called a "heavy water reactor" that can fission natural uranium without enrichment. This reactor design is more accepted internationally since it is very difficult to use it to make nuclear weapons.
Either method of using uranium-235 to fissile however is "inaccessible" to the average person.
Uranium-233 however can be made from Thorium-232 which is readily available. Gas lanterns have mantles made of thorium dioxide. This can be refined into thorium metal. Since all Thorium is of the 232 variety you don't have to go through enrichment processes or use the notoriously expensive "heavy water".
Once you have uranium-233 you can hit it with neutrons and it will fissile.
So how do you go about all of this? very easy:
First you need a neutron source to convert the thorium-232 to uranium-233. To make one you obtain Americium which is found in smoke detectors. Americium produces alpha particles. You combine the americium with berylium (buy it off ebay). the berylium when it hit with alpha particles will produce neutrons.
The neutrons coming off the berylium might be too fat to be absorbed by the thorium, to reduce their speed put a container of water a few centimeters thick in front of the neutron source. Too thick and it will stop the neutrons, too thin and it won't slow them down enough.
Now that you have your neutron source you direct it to a target of thorium metal. as the neutrons hit the thorium they will be converted into uranium-233. Which in turn are hit with more neutrons and eventually fission.
To prove this is happening to your professor you rig up a Geiger counter to continously measure the radiactivity from the sample. First measure the radioactivity before you bombared with neutrons to get a background count. Then place the neutron source near the thorium and measure the radioactivity for a week. If you plot on a graph the radiactivity level you'll see it rise to hundreds of times background level. Then when you remove the neutron source the radioactivity will decrease over the course of a week or two.
What's happening is that the fission products that are produced from fissioning uranium -233 are highly radiactive, this accounts for the huge increase while you're hitting it with neutrons. But they have relatively short half-lives, so when you stop neutron bombardment they will decay away... this accounts for the decrease in radioactivity.
the whole experiment can be done for $100 or less worth of materials. Your university/college if doing nuclear studies should definetly have a sufficiently sensitive geiger counter available for your use.
If you can get access to proportional mode geiger counter then you can identify the fission products and prove that they are being produced.
The method here i describe will not generate enough radiactivity to pose a danger to you but if you inhale or injest the materials then the danger is from their heavy-metal poisioning issues. So be careful and work in a fumehood.
There you go. A simple. Easy "fissible" project that's "feasible" too!!