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Endy0816

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Posts posted by Endy0816

  1. 1 hour ago, iNow said:

    I disagree. This isn't about laws. It's clear he's broken laws, but as rightly mentioned above, he's in charge of enforcing them. For this reason, the founders gave us a political solution, namely impeachment.

    If congress wants to vote him out for liking brussel sprouts more than broccoli or for having too high of a handicap on his golf game, they surely can and that's entirely within their power. It's not about proving anything legally, but is instead about getting both the House and the Senate to agree removal is in order... it's about politics. Senate won't do that, however, because they're a bunch of lilly-livered $*#*s afraid of losing their powerful seat and getting voted out in the next election.

    x-posted with swansont

    I mean he's not guilty until he's been convicted. High crimes and misdemeanors would definitely cover this however. As soon as it passes the House he will have been impeached, so at least that much goes down in the history books.

  2. 14 minutes ago, MigL said:

    Seems kind of strange that a sitting President cannot be removed from office after committing an obvious crime.
    That effectively puts him above the law.

    One step closer to dictatorship.

    It might seem obvious but depends on if it has been proven legally speaking.

    As horrible as it sounds, Trump is in charge of the execution of the laws. Our checks and balances system isn't exactly well balanced right now, but it's all we have to work with.

    Nobody's actually above the law but presidency definitely comes closest.

     

  3. On 11/11/2019 at 10:21 AM, Alfred001 said:

     

    Likely deliberate on the part of your genes in most cases.

    Historically if you have survived that long, you will have proven yourself capable and are likely well set up to provide for any offspring.

     

    Replacement is probably the best route to look at. Most alternative methods are not especially successful. Amount to trying to do something external to impact something internal.

  4. 8 hours ago, bartovan said:

    Interesting diagram, it clearly shows the relation between temperature and pressure, but how does that shed a light on the constant temperature of the system during phase change? Since there's no time dimension? It only shows that with constant pressure, if you raise the temperature from 0 K (or whatever the X origin is), at some point you'll go from solid to liquid, not how long this transition will take?

    In physics, temperature is a measure of the average kinetic energy of particles in a system. The individual particles won't necessarily all have the exact same amount of kinetic energy.

    No phase change takes a set amount of time. It is this whole semi-random process.

    What's really happening is incredibly complex so we have to simplify it so we can make equations and models of the behavior.

  5. Banking(loans) goes back to Roman empire times. Actually mentioned in the Bible in the Parable of the Talents. Closely related, currency exchange is likewise mentioned in it. Jesus purportedly rallied against money changers in the temple.

    Governments would mint based on their reserves of various metals. Coins weren't necessarily pure so still could have inflation.

    Otherwise everything was about the same as now in terms of collecting taxes with the exception that they could also often pay with goods.

  6. 3 hours ago, bartovan said:

    Well yes and no. They do take it to the kitchen:

    "The rate at which heat is added does not affect the temperature of the ice/water or water/steam mixture because the added heat is being used exclusively to overcome the attractive forces that hold the more condensed phase together. Many cooks think that food will cook faster if the heat is turned up higher so that the water boils more rapidly. Instead, the pot of water will boil to dryness sooner, but the temperature of the water does not depend on how vigorously it boils."
    (https://chem.libretexts.org/Courses/Valley_City_State_University/Chem_122/Chapter_2%3A_Phase_Equilibria/2.3%3A_Heating_Curves)

    Probably not how I would explain it.

    phasediagram.gif

    If you consider the phase-change diagram above instead, you can more easily see how you can change from one phase to another and still keep temperature/pressure constant, without issue.

    SwansonT brings up an excellent point about not confusing a model with reality. Highly recommend considering that.

  7. 4 hours ago, bartovan said:

    Thank you for all your answers. J.C.MacSwell makes exactly the point I'm trying to make: according to the theory, 1g of ice in the ocean would make the entire ocean remain at 0°C, which it doesn't of course. And I do believe that in an ocean of pure water this would be exactly the same.

    I have been thinking it over some more and thought of two extremes, as a thought experiment.

    1) Extreme case 1: The heat is applied in one single point at the bottom. In that case it seems inevitable to me that, according to where exactly one measures, different temperatures will be measured. Especially in the case of a very large container with only a tiny fraction of ice remaining (floating at the top of course, to make things worse), when one would measure very close to the heating point, the temperature would be significantly higher than close to the ice. Importantly, no amount of stirring would remedy this (think of the extreme of 1g of ice in 20 000 liters of water, or 1g of ice in the ocean).

    So, in case 1, you simply have different temperatures in different areas, even if you stir, so the diagram doesn't really apply in a literal sense. However, it does make sense, see below point 3.

    2) Extreme case 2: The heat is applied perfectly uniformly (seems impossible in the real world, but it's a thought experiment). (Maybe the microwave experiment of studiot comes close.) So we have a huge chunk of ice at say -50°C and start applying heat in a perfectly uniform manner (meaning: we add kinetic energy to every molecule at exactly the same rate per molecule). In that case the whole block of ice will turn to water in one and the same instant (in other words: at every point, the molecules will reach the necessary kinetic energy to get loose from the solid state), and then, being completely water, will immediately continue to rise in temperature. (Since the phase change happens in one single point in time).

    In this case, the diagram doesn't apply either. You go in a straight, rising line from -50°C to 0°C, then in one single instant (a point in time) you have the phase change, and you continue with a straight rising line. No horizontal part between B and C (in the diagram I posted at the beginning).

    3) So to come back to case 1, I think what the diagram and the theory mean, is that the system, as a whole, remains at 0°C during the phase change in terms of the sum of kinetic energies. Temperature is actually kinetic energy, right? (at least in one of the multiple frameworks for understanding temperature). So during the phase change, some areas will have a rather high kinetic energy (close to the heating point, where they will be excited more), say corresponding to 10°C; while other areas will have a low kinetic energy, corresponding to 0°C or even less in the ice; still others somewhere in between, etc. Probably, during the phase change, the total sum of these kinetic energies is equivalent to the kinetic energy corresponding to 0°C.

    Does that make sense?

    (I propose we leave soup and bishops out of the discussion, since the crux of the question is not really in the "purity" part - see the example of a bit of ice in a gigantic quantity of water).

     

    They're talking about an idealized isothermal process.

    Quote

     

    An isothermal process is a change of a system, in which the temperature remains constant: ΔT =0. This typically occurs when a system is in contact with an outside thermal reservoir (heat bath), and the change in the system will occur slowly enough to allow the system to continue to adjust to the temperature of the reservoir through heat exchange.

    Quote

    Phase changes, such as melting or evaporation, are also isothermal processes when, as is usually the case, they occur at constant pressure.

    https://en.m.wikipedia.org/wiki/Isothermal_process

    Fairly certain it couldn't ever perfectly occur in reality. Always some losses.

    I would recommend taking a look at the ideal Carnot cycle.  Easier to consider it in that scenario Imo.

  8. On 6/15/2019 at 8:27 AM, asd2791 said:

    A while ago I went to the laryngologist, He described a medicine I can not remember his name, But the drug's function is : Drying of the acidity of the stomach, And a doctor told me: This drug also Drying all body fluids.

    My problem was in the throat, But I got another unexpected result, The result is: My sense of smell has become very acute, Before that my sense of smell was weak, That known me, After a period, When I gave up treatment, My sense of smell has weakened again.

    Then I asked myself: Does the nose transfer messages to the brain through nerves?
    The answer is: Yes.

    The conclusion is: The medicine of "Drying of the acidity of the stomach" may affect the whole nervous system, I mean a positive impact, The same effect on "sense of smell", The transfer of messages be stronger.

    Finally : I have a long Anxiety disorder, Is increased fluid in my body have a role in that?
    The answer is: maybe.

    The sense of smell is primitive in comparison with others and have a molecular basis. Imagine a key needing to fit into a lock. Because of this a number of drugs can have an impact.

    I would start by getting the name of the medicine from your doctor.  Then you can check if the bennefits could be replicated or if continued use is advisable.

    Here is a list of some drugs known to have an effect. May help to narrow your search.

    https://www.sciencedirect.com/science/article/pii/S2095881118300234

  9. 14 hours ago, Davide said:

    Reading your post I understand that nothing will ever change in this field.

    Can you imagine if FIAT-Chrysler, before building a new car, must send the project to Renault to be approved? Do you think Renault will say: wow, nice car! go on.

    I am very surprise to see how scientist are naive about scientific publication or, I am the naive one and most of the scientist are ok with that. If I make a favor to you then you'll make a favor to me. It's all a matter of connection. Going to conference, knowing the right people, that's science!

    You can always post a preprint on ArXiv if you're that concerned. The name of the game is not to keep everything to yourself.

    While if successful Fame and Fortune may follow, the main goal of Science to expand human knowledge in a methodical way. You want people to heavily critique your paper. If passed and then later shown to be flawed a bad paper can permanently tarnish your good name and reputation.

  10. 32 minutes ago, Davide said:

    In my opinion is little different. Your "qualified" means to me finding people who are expert in your area of research. This means your direct competitors and, unfortunately, more than you think do not perform a fair review.

    They are likewise relying on you to do a fair review as well. If you don't like it you can go the vanity press route but there's little to stop people from publishing garbage.

    I honestly don't think you could even find multiple people per subject to review papers all day. If you have the skills to review at that level you have the skills to do.

  11. 2 hours ago, Davide said:

    Exactly! the whole review system is wrong. Scientific journals should have their own reviewers instead of relying on strangers which often have conflict of interests or are just to busy writing stupid comments on whatever forum they find in the internet.... So, for example, a reviewer might delay a decision because he/her is trying to publish a similar work or just reject your work because you forgot to say hello to them to the last conference.

    I think this is so prehistoric. Is it only me thinking that the whole scientific publication world must be completely renewed?

    By the way. I resubmitted the paper and after 10 days it was accepted without a single modification. This make me think even more that the first review was delayed (and rejected) on purpose.

    Were the reviewers and the journal all the same?

    Main issue would be simply finding people qualified. It's not like you're submitting an article to a magazine. Even there though can be a significant delay due to the number of submissions.

  12. Works via a cup with holes drilled on the bottom and a piece of tape acting as a simple valve on the top. If the tape is peeled back water/air can flow, otherwise if kept level the water will happily sit there.

    Partially based on thread here a few weeks ago, wanted to prove to myself that this concept would work in reality(beyond a simple straw or pipette).

    Have some thoughts that it might work for novelty applications(fish tanks, water spheres). A somewhat practical, bottom filling bucket could also be done, but haven't figured out a good valve design to minimize manual operation. Goes without saying applications would need to work around the obvious issue, but nothing strictly impossible to deal with. Water locks, pumps, etc.

    Left: Water filled, Tape in place

    Right: Rapidly draining, Tape peeled back

    20191031_163655.thumb.jpg.01b1d6ea3a7210a58ff35f78ce5c32f3.jpg20191031_164517.thumb.jpg.f65c0bb7783e03eebcc3c72361502d13.jpg

     

    Below: Simple model of what a clean version might look like.

    1495153101_BucketwithHolesv1.png.04692e84c9042388ad19e0742e1a0f61.png

  13. We use hexadecimal and especially sexagesimal regularly too. I actually think kids could really benefit from being better educated on the subject. Base 20 might not be my own first thought, but the different Mayan numerals could definitely aid in grasping the concept.

  14. 6 hours ago, Nedcim said:

    It's not an issue with memory. When the thousandths digit of the denominator is changed from 0 to 1, to approach sin40° the answer changes from the correct approximation of 6.14 to 5.13. 

    Memory can also required as the calculator is trying to solve the problem, though Swansont's suggestion is a good one to check.

  15. Probably due to the fact that the calculator has limited memory to handle an infinitely long repeating decimal with as long a period as 3.93/0.64 has. More memory would help in this case for a more accurate answer, but all calculators have a point where they reach the limits of available memory. Pi is another case where you logically know the number should keep going, but instead it stops and/or is rounded.

     

    3.93/0.641=

    6.131045241809672386895475819032761310452418096723868954758...

    6.13104524180967238689547581903276^_ (period 32)
     
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