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John Cuthber

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Posts posted by John Cuthber


  1. 22 hours ago, iNow said:

    One may voluntarily choose to hack their own brain, but one may not involuntarily hack the brain of another. This is a pretty simple and basic concept. 

    Yes, that's a simple idea.
    Now, who gets to choose on behalf of children?

    For example, who gets to choose if babies get vaccinated?



  2. You can choose the "cold" temperature anywhere you like - even above 100C (though that's no longer a condensing boiler).
    The merit of a condensing boiler is that it recovers the latent heat from the water vapour produced by burning fuel.

    The amount of energy that is present depends on the amount of water vapour present, and the amount you reclaim depends on the amount of water you condense.

    The colder you get the outgoing air, the more heat you can recover because more of the water condenses.
    But, the law of diminishing returns sets in.

    By the time you have cooled the air down to 55C you have reduced the vapour pressure by about 85% compared to 100C.

    If you had a perfect mixture of methane and air you would end up with this

    2CH4 + 4 O2 + 12 N2 --> 2CO2 + 4H2O +12 N2

    (I have included the nitrogen in the air, even though it doesn't react.)
    The outgoing flue gas would be 4 /(2+4+12) =4/18 i.e. 2/9 water vapour by volume. (and very hot) That's 22.2% water vapour

    You could run that through a heat exchanger.
    If you were making steam you could run the heat exchanger at 100C (not very efficient but...)
    The flue gases would be at 100C
    At that temperature there's going to be no condensation (at 1 atmosphere pressure)
    Imagine you add a second heat exchanger to warm up the ingoing water.
    What happens when you cool the gas mixture.
    Well, initially not a lot. It just cools down.
    You can use the sensible heat (that's a technical term) to heat the water.
    But, when you get the temperature down to about 63C the water starts to condense out 

    (that's the temperature where the vapour pressure is 22.2% of normal atmospheric pressure- there's a table here)
    https://en.wikipedia.org/wiki/Vapour_pressure_of_water

    As the gas gets cooler, more water condenses out.
    When you are down to 55C, you have reduced the water content to about 15.5% or so.

    And you have reclaimed (very roughly)  22.2-15.5 % of the latent heat. 7% or so.
    If you cooled it to 45C you would drop the outgoing water concentration to about 9.5%
    And that would let you recover more of the latent heat- 22.2-9.5 % i.e. about 12%

    OK, that's better than only recovering 7% of it, but there's a price or two to pay.

    First, you need a bigger heat exchanger.
    Secondly you need to run the system with a cooler return.

    But running a hot water system with colder water is a potential problem.

    So there's a cut-off where it's not considered worthwhile.

    That's an economy decision and, at the moment, the compromise between heat recovery and size (and cost) of the exchanger and the difficulty of getting a hot water system to cool the return water is about 55C

    With bigger, cooler, radiators in the house, you could do better. But that would also be expensive.

    So there's nothing fundamentally magical about 55C.

    It's a compromise.

    (Incidentally, I have ignored the heat that goes into or comes from the air, and also the fact that it expands when hot. I'm lazy and the maths is not helpful here.)

     

    On 1/18/2021 at 10:47 AM, studiot said:

    Do you like being suddenly scalded in the shower ?

    We are talking about the temperature of the cool water return to the boiler.
    It's the hot water from the boiler that scalds people.


  3. 8 hours ago, J.C.MacSwell said:

    which your next door neighbour is unwilling to pay.

    Can you clarify?
    Is he unwilling to pay because he's a selfish bastard who wants to keep the money, or is he unable to pay because his business is not viable and only runs because the guy on $10 per hour also gets handouts (of my tax dollars) from the state?

    8 hours ago, J.C.MacSwell said:

    except I'm the government

    How did you get there?
    Were you voted in by people who recognise that the talk about cottages is a straw man?


  4. 4 hours ago, swansont said:

    And at least half the radiation is going to be sent in a different direction than the face. The phones work, after all.

     

    5 hours ago, John Cuthber said:

    Some of the RF signal escapes to make contact with other phones.

    There's no guarantee that it's half, but it must be some.
    If it was less than half, that would imply a really bad design, but if the proposal is that phones are bad for you, a really bad design is one of the initial assumptions.


  5. 21 hours ago, sadpatato-897 said:

    how much (if any) of that could be down to radiation, and how much down to battery discharge?

    No radio transmitter is better than 50% efficient. (The rest is wasted as heat)
    No battery is perfectly efficient. (Some energy is lost as heat)

    Some of the RF signal escapes to make contact with other phones. (and so it can't be dissipated in the skin as heat.)

    So it's clear that most of the heating can not possibly come from the radiation.

    Incidentally, if I had a pair of gloves that reliably kept my fingers 5 degrees above ambient, I'd be quite pleased.


  6. On 1/16/2021 at 11:54 PM, MigL said:

    Even though your income has been raised above that arbitrary number that the Government chooses to call the 'poverty line'.

    A competent government would have index linked the line so that doesn't happen.

     

     

    I don't have many figures for "affordability" but I live in the UK which has about the fifth richest economy in the world.
    I really don't believe that we can't afford to pay people enough to stop kids going to school hungry.

    I really don't care greatly how we address that issue.
    But a minimum wage above the poverty line or a UBI looks like it's worth trying.
    If only on the basis that everything else has been tried, and has failed. (who remembers "trickle down economics"?)

     

    There is the "but employers will not be able to afford to pay it" war-cry.

    And, as I have pointed out, if that's true then they are not running a valid business and all the free market capitalists should be happy to watch them fold.


  7. It's not that long since the UK introduced a minimum wage.
    The Right wing (Tory) politicians all said it would kill jobs, crash the economy and lead to a plague of locusts etc.

    You know- the things they always say will happen if you do something decent.

    And it didn't happen.

    On the other hand, if you have a minimum wage that's below the poverty line (and we have) then you have an interesting state of affairs.


    A rich man sets up a factory. He buys raw materials and his workers make things.
    He sells the things for more than the cost of raw materials (+ overheads) + minimum wages.
    He pays the workforce minimum wage.
    And, of course, as the owner of the  business, he draws a big fat salary from the profits.

     

    Meanwhile, the government uses the taxes (which I pay) to top up the incomes of these workers.

    But, if the factory had to pay enough that they staff didn't need state handouts, the company would go broke.
    So the owner is being payed a lot- effectively from taxpayers like me- to run an uneconomic company.

    If you set the minimum wage below the living wage, it's a way for rich people to syphon money out of the taxpayers.

    Once they realised this, the Tories were very happy with it.


    Be careful what you wish for...
     


  8. 23 hours ago, Sensei said:

     

    It is easy to verify scientific experiment.

    Grow unicellular microorganisms. Divide into two parts. One will be control group. The second place under smartphone, or even surround by dozen of smartphones, with full LTE / 5G / WiFi turned on all the time during the experiment, under WiFi router, or even put inside of LTE/5G cell-tower, a

    The experiment is so easy that it's done "by accident".

    If there was an effect of the radio waves from 5G transmitters then there would be a change in the growth of the green algae that grows on exposed surfaces.
    Any inhibition of growth would be pretty obvious because the algae would be exposed at close range and 24/7

     

    The experiment has been done, and the answer is that we don't have algae clear patches round antennae.

     

    So we know there isn't an effect on cells..


  9. If the outcome of impeachment proceedings was based in law and evidence, then Trump would have been kicked out last time.

    The right to freedom of speech does not stop there being a law (and indeed an article in the constitution) against inciting insurrection.

    The right to freedom of speech is not absolute; it never has been.

    In the limit, the decision is made by a court.
    The Senate may well decide that telling people to "fight like hell" is not acceptable.

    More importantly, the Republicans may decide that Trump's usefulness has come to and end and it's better to get rid of him in which case- like last time- the law won't matter.

     

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