John Cuthber

http://en.wikipedia.org/wiki/Salmonellosis

" this is a completely seperate issue, is it not, to dealing with separating all of the rare earths? " No, not really. Ce and Eu which have relatively stable oxidation states other than (II) are easily removed. All the others are difficult to split. Even if only two of them are present, the fact is that those two are still very similar and so it's hard to get either of them pure. "If you mean that the commercial extraction processes for the rare earths typically don't take out Pr with Ce, could this not be something to do with the influence of the so many other lanthanoids as are present in rare-earth ores, which aren't capable of being oxidised to a 3+ or higher oxidation state" How, exactly, does an ion know what other ions are present? Imagine a Pr+++ ion in solution wondering whether or not to be oxidised to Pr++++, is there some way where it can say to itself "Oh, I see there's some Ce(IV) over there- that will lower my redox potential"? (and incidentally, you seem to have your oxidation states muddled, they can all be oxidised to "+3 or higher" because they can all be oxidised to +3.) " Your point is valid only if the Ce is taken out first, then the rest of the rare earth elements are treated sepparetely." It is, so it is. Again, shouldn't you have checked? "Lastly, I've said all along that this is project is full of uncertainties" Exactly my point. There is no uncertainty. It won't work. It remains difficult to separate these two elements. I still don't think it's practical as a home experiment.

"I don't see your point here. I don't remember the media glorifying terrorism before 9-11" They call it "terrorism" rather than crime. In doing so they make it sound different, which it isn't. " I don't see our country putting down protestors in such a manner. " Look again. Now, could you let me know how you missed that before?

Does this help at all? http://en.wikipedia.org/wiki/Crystal_radio It's the simplest way to get sound from a radio signal.

How much fuel will you burn to distil the alcohol? Will you get more fuel than you start with?

"If you ignite Pr in air, you get an oxide containing a fair amount of Pr(IV), and I've always considered the highest oxidation state of metals which can be attained by oxidation in air a measure of the stability of that oxidation state in acid solution." There are a good number of cases where elements form stable oxides (and fluorides) which are reduced by water or acid. MnO2 is probably the best known. "Wouldn't Pr be stable enough to stay in solution in acid at least partially as Pr(IV)?" No. " If the observations for CeO2 can be extrapolated to Ce(IV) in acid solution, would this not also apply, albeit to a lesser degree, with Pr?" If they could be extrapolated, but they can't. Apart from anything else, if that technique worked then the Pr wouldn't be there. It would have been removed along with the Ce (which is separatedby oxidation to Ce(IV) during the manufacturing process. Don't you think you should have checked this before suggesting it?

And I'm saying it again. So does WIKI. "Using classical separation methods, praseodymium was always difficult to purify. Much less abundant than the lanthanum and neodymium from which it was being separated (cerium having long since been removed by redox chemistry), praseodymium ended up being dispersed among a large number of fractions, and the resulting yields of purified material were low. " If you look here you will see a lack of Pr(IV) compounds http://en.wikipedia.org/wiki/Category:Praseodymium_compounds The Pr(IV) ion is a very strong oxidant. If you treat Pr2O (3-and-a-bit) with acid it dissolves to give Pr(III) and O2. The water gets oxidised.

Dogs chase cars. I suspect, but can't prove, that they just like chasing things. The fact that this often leads them to their lunch may not be evidence of pre planning as such. It's just that the proto-dogs who didn't chase things starved.

It's difficult to heat treat Ti without it picking up enough N or O to make it brittle, but that's not a property of TI itself.

Many of the bugs will be hiding between the bristles of the brush. The bristles are most probably nylon. Nylon is opaque to hard UV. The UV will not reach some of the bugs. The UV light probably won't kill many bacteria.

Just for the record, titanium is not brittle.

The UV light probably won't kill many bacteria.

"I have little sympathy for them" Then it's probably just as well that you won't be choosing their fate.

Well, I guess he was mistaken when he said it was "pretty close". Anyway, there are indeed, generally 2 inputs on a scope (3 if it has a modulation input too). The point I was making was that you can add two signals together say a sin(x) and b sin (3x) then plot that against , for example c cos (x). If a and c are equal and b is zero you get a circle. If b is non-zero then you get another pattern. That's the equivalent of looking at a distorted sine wave vs a cosine. I'm not certain how much use it would ever be- but the patterns can be pretty.

"All you have really shown me is an article that 'proves' the current crop of smokers etc are a drain on public health system when they are treated for their smoking related chronic illnesses and kept alive for longer rather than being denied treatment and allowed sentenced to die."

This sort of thing? http://en.wikipedia.org/wiki/Hemodialysis#AV_graft

The OP didn't. Incidentally, if you take a fast sine wave and a long bit of cable you can make a circular Lissajous figure. Also, if you combine more than 2 together you can get other pretty patterns.

http://xkcd.com/925/

He's making a bad joke about an alternative use of the word "graft". Anyway, the simple explanation is that you can make a polymer molecule with some groups in the chain that are easily broken by UV. If you add another polymer then shine UV on the mixture the broken ends of the first polymer chain can stick to the second polymer giving a sort of "alloy". http://en.wikipedia.org/wiki/Copolymer#Graft_copolymers

This sort of thing? http://en.wikipedia.org/wiki/Potentiometer_(measuring_instrument) I can't see the point of a transformer- they only work with AC and a cell like that will never produce AC.

If you have an authentic sample that makes things a bit easier. Do you have a voltmeter of some sort?

Do you mean this sort of thing? http://en.wikipedia.org/wiki/Lissajous_curve

Shortly after the big bang everything was plasma. Any dust that now exists...

"And only those preventable diseases that would give the biggest bang for the health buck to eliminate. That would not include disabled children who are kept alive. " Make up your mind.

"It is not about peoples' attitudes towards these risk factors. " Oh yes it is. It's the same people who have that attitude that vote for the political decision. "As I said, in Australia, the medicare levy should be a sliding scale based upon lifestyle as well income level." Fine by me: I don't live in Australia. "Currently there is little or no accountability for lifestyle choices " Yeah, I mean, like- you know- the only thing I have to worry about is dying. And that's not really important is it? "The amount of you medicare level should be proportional to the number and type of risk factors you choose to ignore and subject to a compulsory annual medical check up." With the addition of the word "inversely" this could be taken seriously.