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John Cuthber

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Posts posted by John Cuthber

  1. "They don't do that -- they make slight changes in BOTH directions and then observe the results. That's what a good scientist or engineer does. "

    Sometimes it's not practical to make those changes- you just have to look at other systems. (This is perfectly valid science- nobody ever tells an astronomer to watch a star for 5 billion years to see what happens; they just tell them to compare it with an older star).

    What happens if we look at some other healthcare systems.

    My understanding is that if you make the comparison you find that Americans have healthcare that is among the most expensive in the world and the least "socialised" in the world.

    If they had the longest lifespan in the world or the best general health during that life there might be a reason for the expense. I don't think they do.

    Could that be telling us something?

  2. The phenylalanine is almost certainly from aspartame.

    Rinsing a bottle with bleach and leaving it for a while will kill any bugs in the bottle (unless the bottle is really dirty). Rinse out the bleach with clean water and you should be OK. It's still a good idea to empty and fill the bottles from time to time in order to rinse out anything that's started growing.

    The triangele with a 1 means the bottle is made of PETE which is probably the commonest plastic used for drinks bottles. The big scare was about polycarbonate rather than PETE.

  3. Just a thought; what would evolution do to trees that had a habit of spontaneously combusting?

     

    A rotting tree stum is another matter. It's not that different from a wet haystack catching fire.

    Before you say that a tree spontaneuosly caught fire you would have to rule out the other explanations (like a cigarette butt thrown from a car).

  4. I'd like to volunteer for this. How much does it cost to be a volunteer?


    Merged post follows:

    Consecutive posts merged

     

     

    Who would it be problem for?

     

    Subcutaneous adipose tissue is necessary in moderation. Visceral adipose tissue is not at all necessary and is in fact detrimental to health.

     

    If that were true then I'd like to know why evolution hadn't wiped it out long ago.

    Or are you saying that you are cleverer than a few billion years of evolution?

  5. "mr = G/2 shows that all elementary particles are compactions of a single elementary particle"

    Explain what that means, then prove it.

    Then, maybe, I will bother to look at the rest of it.

  6. "A misunderstanding has occured mainly due to the way I worded the statement referred to."

    While you wait for the reply from the BL, why don't you tell us what you thought you meant?

     

    The references won't tell you anything new.

    There's an effect of neutron number on atomic radius but it's tiny and already explained in terms of zero point energy.

     

    Incidentally, does the fact that you are now looking for references mean that you were previously posting stuff for which you had no evidence?

    It certainly looks that way to me.

  7. Your first post in this thread said "The e:N line is smooth indicating that it determines atomic radii, "

    Now you are saying "I never claimed the amount the atomic radius is affected by the number of neutrons was large or small"

    If the number of neutrons determines the atomic radius then it has to be a big effect.

    In fact it's tiny as I already pointed out, with data, twice.

  8. Since this is a scientific site we ought to be able to assume that where no unit is specified it's the SI unit; so he should be looking for chickenwire

    (hole size about 2*10^-2 M).

    Somehow I doubt that's right.

  9. All radii given by Emsley are classified as 'nuclear data', but he does not define that as applying only to the nucleus.

    I use 'atomic radii' the measurement found by experiment.

     

    I have yet to find or be given a reference to a work that states specifically that 'all isotopes of a given element have the same radius'.

     

    No, but I have given you two specific instances where they are practically identical.

    On the other hand you have offered no evidence at all.

    Do you understand why that's a problem?

     

    Also, have you understood the difference between a nuclear radius and an atomic radius yet?

     

    And, just to reiterate.

     

    If the neutrons are responsible for atomic radii then how come the radii don't change when you change the number of neutrons?

     

    If your next post doesn't give a clear, valid answer to that question then give up on this idea.

    Misunderstanding a book doesn't count as a valid answer.

  10. Can you measure the water instead. A Karl-Fisher titration is the complicated but sensitive way or you can dilute a known mass of it it with a solvent like isooctane and distill the water (and isooctane) out. Ideally you do this in a Dean-Stark aparatus. If there's enogh water it forms a layer at the bottom. If not you are stuck with the K-F titration.

  11. To be fair John Emsley is a well respected writer.

    A quick picture of the relevant page would be nice.


    Merged post follows:

    Consecutive posts merged

    By one of the odd coincidences that you sometimes find I have found a paper that does look ath the difference in atomic radii for different isotopes. They are only looking at silicon and, in particular at the difference between highly enriched 28Si and the natural mixture (which contains about 7% of to other isotopes).

    The difference is a massive 1.95 parts in a million.

     

    I don't know if you will have access to this paper, but here it is.

    http://www.iop.org/EJ/article/-ffissn=0026-1394/-ff30=all/0026-1394/46/5/005/met9_5_005.pdf?request-id=888aa37d-0832-4a7d-bf17-c78f67983581

     

    The coefficient of thermal expansion of highly enriched 28Si

    Guido Bartl, Arnold Nicolaus, Ernest Kessler, Ren´e Sch¨odel and Peter Becker

    Metrologia 46 (2009) 416–422

    stacks.iop.org/Met/46/416

  12. If there were no methane observed elsewhere in the universe and if (big if) we could assume that all life is similar to that on Earth and generates methane, then we could say that there is no life elsewhere in the universe.

    However to assert the converse - "There is methane therefore there is life" is as silly as saying that all alsatians are dogs therefore all dogs are alsatians.

     

    There can be methane in the universe at large whether or not it contains life and Widdekind just doesn't seem to realise this.

     

    Since he also doesn't seem to realise that life is more complicated than a rock and that the same arguments he has used sugest that everyone is a fortysomething bloke with a beard and that the universe is full of blast furnaces, it doesn't shock me that he can't understand this latest problem.

    His maths seems pretty ropey too.

    Worst of all, he doesn't answer direct questions.

  13. I don't think I need to do any more study on this.

    If you distill wet toluene the first thing that comes over is the azepotrope at 85C. Once that has removed all the water the next thing to come over is dry toluene at 111.

    They do not comee off at the same temperature.

     

    Toluene is not the same as a mixture of toluene and water (about 20% tol 80% H2O IIRC) They have different boiling points and one of them settles out into 2 layers.

     

    As I pointed out, there's never much water in toluene (about 0.05%) so the azeotrope will remove all of it.

     

    What's your problm with this? It's been used as a method for drying toluene for ages.

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