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John Cuthber

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Posts posted by John Cuthber


  1.  

    I found some sort of helpful data
    https://www.nist.gov/system/files/documents/srd/jpcrd425.pdf
    Page 1155 tells me that at 1000 MPa and 290K the density of methane is 571 g/litre

    So, even at ten thousand bar the pressure isn't high enough to raise the density to that of liquid methane at its normal  boiling point.

     

    So, if I have got the arithmetic right, the use of the ideal gas equation gives you an answer that's at least ten fold wrong (and I have no direct data about how much worse it actually is).

    At half that pressure the density is about 497 so the density doesn't change very fast with pressure. That, in turn suggests that even at 20KBar the density would be less that that of the liquid

     


  2. 5 hours ago, YJ02 said:

    its really quite easy to find on any search

    here you go, took my about 20 seconds:

    https://www.nationalreview.com/2019/11/trump-impeachment-inquiry-illegitimate-ten-reasons-why/

     

    As far as I can tell, none of those is actually valid.

    That's not to say there aren't viable claims to be made; just that the report you cited doesn't show them.

    It's interesting to note that the Left is saying that the impeachment action is in support of justice, rather than their cause.- They may be lying.

    What is the Right's justification for opposing it?

    Do they not want an investigation and hearing that  would clear their guy and make the opposition look stupid?


  3. 20 hours ago, swansont said:

     

    Better than the one you’ve offered, though.

    Fair point.
    OK imagine I fill a tank with liquid methane at its normal boiling point.

    The density is 0.656 kg/litre

    And if I close the tank and let it warm up then (ignoring the deformation of the tank)  the density will stay the same, so I need to find the pressure where gaseous (strictly, supercritical) methane has that density at room temperature- say 20C or 293K.
    I spent a while trying to find data for that, but I couldn't. I will have a look when I get  back to work, to see if anyone has the data.

     

    On the other hand, if I use pv=nrt well, p=nrt/v

    I have chosen v= 1 litre

    the mass is 656g 

    That's 41 moles so n = 41

    r = 0.0813 litre bar / k/mol

    About 950 Bar (I think- feel free to check).

    However, fundamentally, the reason I said it was a way of estimating the pressure badly is that you are using the ideal gas laws- which assume that the compressibility of a gasi is quite large. 

    However, you are actually considering a supercritical fluid.

    Gases are easy to compress because they are mainly empty space.

    That's not the case with supercritical fluids where the molecules are nearly "in contact" with one another. If the molecules are "in contact" then you have a liquid

    In the case of liquids, the compressibility is tiny- for most  practical purposes water is regarded as incompressible, for example.

     

    So, to get the 656 g of supercritical fluid which (near the critical point) has a density of 0.562 kg/l into a 1 litre tank you need to compress it by a factor of about 85%.

    Now, I know it's not the same thing, but to compress water to that extent the pressure needed is huge.

    The compressibility is about 0.5% per 100 Bar

    And you are trying to compress it by about 15%
    That's about 3000 bar.

    Methane is going to be about the same ballpark.


  4. 3 hours ago, dimreepr said:

    He never deliberately hurt anyone.

    Did he ever knock his opponent out?

     

    5 hours ago, Prometheus said:

    What? Sorry, i just don't know what you're trying to communicate. Maybe someone else who understands your point can try to articulate it in a different way.

    X increases health risk by a. Y increases health risk by b.

    a < b.

    Society will ban something if the health risk >= b. Therefore Y is banned.

    Tell me where intention comes into this equation. 

    In general cutting someone's leg off is banned.

    But removing a gangrenous leg, to save the patient is permitted.

     

    In both cases, harm is done- the guy loses a leg.
    But in one case the intent (even if the operation fails) is to help them.

     

    Also, if this"Society will ban something if the health risk >= b. Therefore Y is banned." was right, the drugs policy would be utterly different.

     

     

     


  5. 3 minutes ago, Prometheus said:

    99% of a boxers time is spent outside the ring

    That's relevant if cricketers typically spend the night on the field.

    Are you saying that, because it is premeditated- they trained and practiced to deliberately hurt people- it is somehow better?
     

    As far as I can tell, that's the opposite of the view taken society (as codified by the courts.)


  6. 1 hour ago, Prometheus said:

    So sometimes consent is valid and sometimes not. What you have still failed to address is why consent in boxing is not valid, and consent in rugby, say, is.

    Because, though you repeatedly fail to accept it, there is a difference.

    You do not set out to brain damage your opponent when you play Rugby.

    Do you accept that there is a fundamental difference between boxing and other sports?

    I can only presume that you don't understand the difference.

    The difference is that of intent.

    Like the other difference you don't seem to understand- that between pharmacology and murder.

    Giving people physiologically  active chemicals  might be homicidal, or it may be medical.

    The difference rests solely on why you do it.


  7. 10 hours ago, Prometheus said:

    So? Why does that make rugby OK even though it has a higher risk of mortality and morbidity than boxing?

    The difference between pharmacology and murder is intent.
    Civilised societies do not judge  only on the outcome

     

     

    10 hours ago, Prometheus said:

    And you seem not to understand it is done with the consent of the other person.

    I understand that there is consent.
    I also understand that the law doesn't  always recognise consent.
    "In the UK, in Operation Spanner, three men who consensually agreed to engage in consensual sadomasochism, were convicted of assault occasioning actual bodily harm. The resulting House of Lords case (R v Brown, colloquially known as "the Spanner case") ruled that consent was not a valid legal defence for wounding and actual bodily harm in the UK, except as a foreseeable incident of a lawful activity in which the person injured was participating, e.g. surgery. "
    Currently "Boxing"- by the Queensbury rules" is lawful and knuckle fighting is not.

    Had you checked on that before telling me I didn't understand?
     

     

    10 hours ago, Prometheus said:

    The question then is where we decide to draw the line. Surely the rational approach would be decide what level of risk society is willing to tolerate. In which case swimming, rugby and ice hockey would need to be banned before boxing, as the evidence i shared suggests they are more harmful.  

    That sort of decision making is, essentially, what I do for a living.

    You have made a common error.
    You have  only got half way to the well established idea of a "risk/ benefit" analysis.

    By your "logic" we should ban cars- since they kill more people than rugby.

    The "benefit " of boxing is, largely, the entertainment of the people.

    If the crowds were big enough, would you think it was "right" to feed Christians to the lions?
     


  8. 18 hours ago, Prometheus said:

    If your concern is really the risk of damage these people are doing to themselves, 

    They don't hit themselves; they hit each other.

    That's the point.

    18 hours ago, Prometheus said:

    That's your opinion. You need a better reason...

     

    It's also the opinion of the society which expects teachers and other adults to stop kids fighting in the playground.

    19 hours ago, Prometheus said:

    And more generally, why do you get to dictate how much risk another adult should take with their health?

    You seem not to understand that it's other peoples health they actively seek to damage.
    But the answer is obvious. your point is  a strawman.

    It's not my decision, but society's.


  9. On 12/3/2019 at 10:21 PM, Prometheus said:

    As long as the fighters are aware of the risks and the referees and trainers primary focus is ensuring the safety of the boxers i don't see a problem. 

     

     

    Unlike any other sport, where harm to the opponent is incidental to the process, the primary goal of boxing is to brain damage your opponent.

    The euphemism they use  is "knock out".

    So, if those involved want to make the "sport" safer, they have to reverse the rule; a KO should lose the match.

     

    Fundamentally, this is grown men (in the ring or the audience) doing something they should have  grown out of while at school.


  10. On 12/2/2019 at 2:37 PM, studiot said:

    Yes you are correct an I would be interested in your ideas as to how the experimental results might have come about.

    Let's face it. I'm not shy.

    If I had any meaningful suggestions for an explanation, I'd put them forward.

     

    I will make one point.

    It's not a difficult experiment to set up.

    Anyone with any "theory" about what went wrong could repeat the experiment.

     

    I found this on the web. Are their data concordant with yours?
    https://pennyroyalresearch.files.wordpress.com/2017/01/the-effect-of-temperature-and-concentration-on-galvanic-cells.pdf


  11. On 4/4/2016 at 5:53 PM, Enthalpy said:

    As is, it doesn't exist liquid at room temperature, whatever the pressure.

    A few years ago, Enthalpy made that simple, easy to understand observation.
    And yet we still have people asking things like this.

    22 hours ago, Moreno said:

     What pressure will they need to hold when LNG will get ambient temperature?

     


  12. On 11/29/2019 at 4:55 PM, studiot said:

    Just spotted this, which may be the problem.

     

    I don't know what your resistor(s) were in series with the electrometer but I think the input resistance to the meter might have been to high.

    5x1013 Ohms is huge.

    Can you repeat with something like 10 to 100 MΏ in parallel with the meter?

    I assume you had selected voltmeter mode?

    Ideally, the input resistance of a voltmeter is infinite.
    10^13 ohms will be close enough.

    Putting a resistor in parallel will slightly reduce the accuracy of the measurement.


  13. 1 hour ago, Arnold Ungab said:

     of course i need the media

    No, you do not.

    As I said...

    19 hours ago, John Cuthber said:

    You don't need the media to do the experiment I proposed.

    So, get out and do the experiment.


  14. 4 hours ago, Arnold Ungab said:

    @John Cuthber  if you choose not to believe its fine...  most people don't believe it anyways.... but if want to DIG more of it try to search my name in DAVAO CITY PHILIPPINES  for sure you can find rumors about me.. my name is ARNOLD UNGAB i use my real name on purpose just incase they will dig my name and find clues about me. I told you before this is a joke , troll or a fake new mostly NOT a fake story. i've been contacting alot of news media hopefully they will give a chance to prove it along with skeptics and you shall know that i'am the real deal. thank you very much

    It's not a matter of what I believe, is it? After all, it's not as if I post under my real name here, so I recognise that a name isn't important.

    It's a matter of your assertions not making sense.

    Either you have experimental subjects or you don't.

    You don't need the media to do the experiment I proposed.


  15. 45 minutes ago, Arnold Ungab said:

    1. i can send random messages to a person and the person heard it, that includes words numbers and symbols.

    Either you are wrong, or you are wrong.

    Either you can send these messages to people, and they tell you what they "heard" or they don't.

    If they don't then you are wrong to say ". i can send random messages to a person and the person heard it, that includes words numbers and symbols.".

     

    On the other hand, if you can send those messages then you are wrong to say that you can't find experimental volunteers because the people who tell you that they "hear" your messages are experimental volunteers.

     

    Chose a story , and stick with it, or just leave.

    9 hours ago, Arnold Ungab said:

    I'am not confused, mentally ill or insane

    If that's true, and yet you are saying things that contradict eachother then you must be lying.

    However, here's a simple experiment for you to try.
    Go for a walk through town of go + hang round at the bus station or some such- anywhere that you can find plenty of people.

    Wear something slightly unusual- a red coat or something.

    Telepathically send a request to anyone who passes you saying " Ask the guy in the red coat what the time is".

     

    Now I accept that some people who "get the message" will ignore it but it's hard to imagine they all will..

    Try this experiment for a few hours  over a few days and come back to us to let us know if anyone actually asked you the time.

     

    Once you have enough data - say a dozen people asking you the time,- repeat the experiment, but this time send some other message and see how many people ask the time anyway,- just to establish the background rate.

    If you are really telling the truth, you should be able to confirm it in an afternoon.


     


  16. On 11/21/2019 at 9:46 PM, mistermack said:

    So, in your view, the evolution of dogs started with domestication? I think you'll find that it goes back millions of years before that. 

    Which variation of stupid are you being?
    The evolution of dogs and people started at the same time since (like all mammals) we have a common ancestor. That invalidates your claim that our pet dogs have had longer to evolve than we have.

    And you said "pet dogs" and they only became pet dogs after we started petting them. That invalidates your claim that our pet dogs have had longer to evolve than we have.


  17. 3 hours ago, Arnold Ungab said:

      i would like to test that theory but the sad truth is there will no more willing participants in the exercise. 

    Are there any homeless people where you live?

    How about students or bored housewives?

     

    This idea that you can't find  experimental subjects is daft.


  18. 1 hour ago, mistermack said:

    We simply haven't got the long period of evolution of surviving chills that our pet dogs have, 

    We have been around for longer than pet dogs.It kind of follows from the definition of "pet".

     


    And "Where the domestication of the dog took place remains debated, however literature reviews of the evidence find that the most plausible proposals are Central Asia, East Asia, and Western Europe. "

    From
    https://en.wikipedia.org/wiki/Origin_of_the_domestic_dog
     

    So, that's plainly after we left Africa.


  19. "for copper electrorefining is 0.0 V. In practice, overvoltages at the anode and cathode and the resistance in the electrolyte and electrical system result in the need for an applied voltage of approximately 0.3 V. "

    From
    http://doccopper.tripod.com/copper/er.html

     

    Or 0.15 to 0.3V from

    http://www.ct.ufrgs.br/ntcm/graduacao/ENG06631/5-b_copper.pdf

    I recognise those are for copper, but silver's not that different. 

    So the energy use is roughly  a tenth of what you said.
    0.02MJ / mole

    Now a MW Hr of (domestic) electricity is 3.6GJ and costs- as you say about 150 Euros

    So that's 4 cents per MJ

    So the electricity cost is 0.02 MJ/ miol times 4 cents per mol which is 0.08c per mole

    Roughly 10 moles to the Kg

    so the electrical cost is about  1 cent per kilo or about 10 Euros per tonne. Today's price is about 500 euros per kg or roughly 500,000 per tonne.

    Essentially, unless you can recover 90% or so of the energy that you put into evaporating the metal, it's not worth it

    Electro refining at about 0.02 to 0.05 MJ / mole is going to be cheaper than boiling at 0.3 MJ/ mole, even when you allow for gas being roughly a third the price of electricity (on a J per $ basis)..

    On 11/16/2019 at 3:47 PM, John Cuthber said:

    Good luck making it cheaper than electrorefining.

    Running it in a stream of argon means you also spend energy heating argon.

     

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