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John Cuthber

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Posts posted by John Cuthber


  1. It's an interesting idea.

    Imagine that some state decided that you could get the "right" answer by saying " my religion tells me so".

    Imagine the pupils  studying and passing exams under those conditions.

    And then imagine them looking for work.

    Employer " I see you sat your exams in such and such a state"

    Candidate "Yes, that's right"

    Employer- "That's the state where you can pass exams by getting the wrong answer, isn't it?

    Candidate "Yes, that's right"

    Employer " Next candidate please".


    Now, I think that most students would recognise this problem quite quickly and would actually object to any such absurd legislation.


  2. 1 hour ago, Joduh said:

    If I'm just to be trashed, I'll refrain from posting the rest of it.

     

    Science makes progress by trashing ideas that don't work.

    If you are not happy with that, try another field.


  3. Manuka honey is a very very expensive way to buy sugar containing variable traces of nothing-special antimicrobials.

    Why not just go to the local supermarket or pharmacist where they stock a wide range of antibacterial products that are known to work reliably?

     

    Some are even perfumed with essential oils.

    21 hours ago, Alfred001 said:

    Can you think of any cheap, natural substance with broad antibiotic properties that I might use for this purpose?

    Why specify "natural".

    Natural does not mean "good" or "safe".


  4. It's an interesting idea. Even if you just split them into a few groups- high boilers, medium and low, you  might make a second step so much easier as to be worthwhile.

    I'm pretty sure they will react with carbon.

    I suspect that you are near enough to the melting points of all but the most refractory metals that they wouldn't have the mechanical strength to build vacuum chambers from (unless you happened to be on the Moon).


  5. 1 hour ago, Longwell3 said:

    Do the bigger chunks rejected by the intestine cause kidney stones?  

    Stuff that's not digested by the intestines leaves by a different route.

     

    Calcium ions will form a solid precipitate with, for example, phosphate. Calcium phosphate can form kidney stones (and also bones).

    It is still calcium in the form of ions. Calcium metal reacts instantly with water.


  6. 13 hours ago, studiot said:

    Calcium is not absorbed in the stomach,

    I never said it was.

    I said CaCO3 dissolves in the acid in the stomach- it does-and I said that the calcium is absorbed- it is.

    I never said where it was absorbed so...
     

    13 hours ago, studiot said:

    Please check your facts before you quibble.

     


  7. 1 hour ago, dimreepr said:

    Curious use of the word humble, in this context,since it's only religion that teaches humility and strangly not off topic.

    Religion(s) tried to pretend that we were the centre of the universe and that other religions were so wrong they were evil and should be killed for it.


  8. There are two major ways that food "goes off".

    • Bacteria or other micro organisms grow on it or
    • it is intrinsically unstable.

    You can kill the bugs by pasteurisation. However, something that has more sugar than anything else is probably not going to be attacked by microbes.

    (Jam is a way of preserving fruit by adding so much sugar that there is not enough water for the bacteria.

     

    On the other hand, mixtures of fat and water (like butter) are  not stable. Even without bacterial help they go rancid.

    There's not much you can do about that except keep the product cold.

     

    What happens to the buttercream if you leave it (in a closed container ) for longer than the shelf life?

    That might help you work out how it is going off and that will help you work out how to prevent that change.

     

     


  9. 2 hours ago, RaytjeKn said:

    But would like I asked earlier it just be a matter of soldering the wires (PICTURE BLUE) to the ring and removing the epoxy glass (PICTURE YELLOW).

    If you do that the aluminium will short circuit the resistor and you won't get a reading.

    There are glues that will stand 210C without any trouble

    The biggest problem you face is that an object like that ring, in air, doesn't have " a temperature".

    Bit's of it will be warmer than others.

    2 hours ago, RaytjeKn said:

    I think it should be as easy as connecting the wires of my multimeter to the probes of the RTD without any other circuitry, read the readings of the multimeter (Ohms) and see what the according temperature would be.

    It should be.
    It's not going to be the most accurate measurement in the world, but you probably don't need that.

    You can improve the accuracy significantly by putting some sort of insulation on the temperature probe so that   the air doesn't cool it much. A scrap of glass  wool is probably good enough


  10. 2 hours ago, Sensei said:

    Compounds (especially complex organic compounds) heated in oven to couple hundred degrees will decompose to smaller unknown compounds, and eventually get into random reactions with other compounds around them (e.g. other pesticides or by-products of decomposition etc.), and product of reaction might be eventually harmful.

    The toxicologists take this into account.

    It is called "cooking".


  11. Swansont's  actual day to day experience says it is.

    Which are you going to believe?

    Incidentally, if you want the "high school science" explanation, remember that lines of force repel one another.

    So they spread uniformly through the bore of the solenoid in order to keep as far from eachother as possible.

    Why would they not?

     


  12. 39 minutes ago, swansont said:

    .  In e.g. hydrogen, you could flip the hyperfine state, which is the 1420 MHz transition.

    You can get that transition, but the classical interpretation (i.e. the one involving an actual rotation) is that it is only the electron which spins, not the whole atom.

     

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