exchemist
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Posts posted by exchemist
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1 hour ago, Sensei said:
Without the attack on Ukraine, there would not have been this (and thousands of other) tragic accidents and senseless deaths.. 100% V.P. responsibility.
V.P. soldiers are also attacking from Belarus, Transnistria, Crimea and warships at sea.
What has that to do with the origin of these two missiles?
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12 hours ago, Moontanman said:
Reports are coming out that Russian missiles have landed in Poland and killed at least two people. Is this enough to allow attacks on Russian soil? Should retaliation be swift or should we hump up and take this as Ukraine has done?
Different picture this morning. Seems the trajectory puts it in doubt that the missiles came from Russia, though they may be Russian-made. Could be Ukrainian missiles, attempting to shoot down the Russian ones, that went off course.
Even if they did originate from Russia, it is very unlikely this would be deliberate escalation. Far more probable it was guidance error or something. Everyone should keep calm.
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4 hours ago, Nigthwishxd said:
Hey, thanks for looking into this!
n(NaOH)= 0,2g/39,99= 0,005 mol
Ka =10^-4
End [H3O] =10^-3
Equillibrium after adding base, I have no idea how this should be formulated to solve [HA] in the beginning.
OH- + HA --> A- + H2O
10^-4= (10^-3)x(X+0,005)/(X-0,005)
It's a long time since I did these, but I suspect the key is the equilibrium constant for the dissociation of the acid. NaOH is a strong base so it will mop up essentially all the H+ it can react with, leaving you with a lot more A- than H+. So that will tell you how much extra A- you have, and you know how much H+ there is from the pH at the end. So by plugging these into the formula for the equilibrium constant, I think you have enough information to construct an equation to solve for the unknown, don't you? But I admit I have not yet got out pen and paper and tried.
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22 hours ago, Nigthwishxd said:
Hi! I have tried to solve this for few days but can't get the right solution. It seems so simple! This makes me wonder if I still miss some basics >-<
0,2g of sodium hydroxide was added to 1,0l of an aqueous solution of the monovalent acid. An addition after, the pH of the solution was 3,00. How many moles of acide were dissolved in the water before addition of sodium hydroxide? The pKa of the acid is 4,00. The addition of sodium does not change colume of the solution (t= 25°C) The correct answer is: 0,066mol
Where have you got to before you get stuck?
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11 hours ago, Markus Hanke said:
The terminology is mostly for historical reasons, I think, though of course (at least in the case of Schrödinger) many of the physically relevant solutions to these equations are wave-like. But, as exchemist has pointed out, technically speaking they are diffusion equations.
In fact, is it not the case that the time-independent version of Schrödinger's equation is a wave equation, of the type appropriate to standing waves? I presume that would have been the first application of it (H𝚿 = E𝚿), back in the 1920s, as I think Schrödinger originally applied himself to the question of an electron in a bound state in an atom. If so, it would have been in its original form a special case kind of wave equation. When the time dependence was added to make it more general, that would have been the point at which it became a diffusion equation.
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1 hour ago, Externet said:
Repeatedly see illustrations on how extensive the ice age was thousands of years ago, covering to about 45-50 0 lat.N and beyond. But never see the same depicted for southern latitudes. How was the equatorial climate and temperature then ?
And the equatorial flora + fauna did adapt and evolved in such 'short' amount of time to now tropical temperatures ? Or was the temperature gradient such brutal from the icy edges to equator ?
There is almost no land higher than 45 deg south of the equator, apart from Antarctica. Just the tip of S America.
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13 minutes ago, computer said:
I meant free electromagnetic field equations that we can write like this:
∂E/∂t = 1/ε0 · curl H
∂H/∂t = - 1/μ0 · curl E
F = sqrt(ε0) · E - i · sqrt(μ0) · H
- i · ∂F/∂t = c · curl F
Thank you for you answer. I am still wondered why in quantum mechanics functions have prefix "wave". If we get double time derivative, it will be proportional to "nabla in the fourth power", when in typical de Broglie equation only second power (div grad or curl curl, depending on the type of waves, longitudinal or transverse). Has it to be so?
You have a point, I think. As I recall, Schrödinger's equation is not a true wave equation because it only has a single rather than double derivative with respect to time. I think I remember Peter Atkins telling us it is more properly a diffusion equation, rather than a strict wave equation.
He went on say, rather enigmatically, that it might be thought more appropriate for a description of the behaviour of matter to be governed by a diffusion equation.............
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11 hours ago, occultist said:
What is out there to help us track and compartmentalize these biases that we all have? It seems intellectually counterproductive to keep the notion of the various elements of the human condition and its origins scattered and unmanageable. Mars 360 gives us a model, a framework, something we can work with and its all based on statistics and demonstration. The book also ties it to Abraham Maslow's hierarchy of needs , dark matter, and quantum theory. What more can an intellectual ask for?
What corrects individual biases is reliance on collective perception, rather than that of individuals. That is why science relies on reproducible observation rather than individual anecdote.
Your next sentence, about elements of the human condition, seems to be a non-sequitur. It is not clear how that relates to anything that either you or I have mentioned up to this point.
As for what more an intellectual can ask for, the answer is a coherent idea, clearly expressed and supported by evidence. As others have already pointed out on this thread, you have yet to come forward with anything like that. Referring us off-site to a book is not acceptable here. You need to lay out your ideas here on the forum where we can all see them and discuss them.
But I have to reiterate that basing something on a concept like astrology that is well known to be pseudoscience, is not a promising start. This link evaluates astrology against the criteria for science and shows why it is not science but pseudocience: https://www.learnreligions.com/astrology-is-astrology-a-pseudoscience-4079973. I realise you have posted in the Philosophy section but this is a science forum and readers here are unlikely to give credence to ideas that fly in the face of science, even in philosophy.
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2 hours ago, kenny1999 said:
approx. 200ml 13-14% alcohol by volume every day, does it exceed daily alcohol limit recommended?
Somewhat. The UK recommended max. weekly consumption for men is 14 units, a unit being 10g of alcohol. What you describe is 2.7units/day which is a bit over this.
I have a particular interest in this as I have a tendency to a heart arrhythmia (A Fib) and so I need to manage my alcohol intake, which I control to ~12 units/week. It is also advisable to ensure you have several days per week when you do not drink alcohol. This gives your liver and other organs a chance to recover from its effects. My practice is to consume 3-3.5 units per night, on Friday Saturday and Sunday (i.e. 1 bottle usually French wine), and then no alcohol Mon-Thur, except sometimes one mid week beer (2 units). Having some nights when you have no alcohol are also beneficial as you tend to get better quality sleep.
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39 minutes ago, occultist said:
The book posits that the position of Mars in one's birthchart influences their outlook towards certain things. So essentially a person's Mars placement could in fact deter them from even believing in the influence of Mars. This is what is remarkable about the Mars 360 system. It actually takes into account those Mars factors that would keep a person from believing in the system or ascribing to any system for that matter
Do you believe that there is a mechanism that drives your outlook towards certain ideas, or do you believe that you are above such factors and that your ideas, feelings, and suppositions as well as your improvisation on those are based solely on your freewill and not driven by certain other factors that are innate and immutable?
We all have biases, sure. However that is not to say that any nonsensical idea can be put forward to account for them. Astrology, in particular, is demonstrably bunk.
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1 hour ago, occultist said:The book "The Mars 360 Religious and Social System" lays out a greater justification for belief in its doctrine than any other holy book in history. It takes astrology and turns it into a matter of life or death and has faith inducing mechanisms that could turn it into the next major religious system. This new religious system is equpped with a god, a currency, and a new morality that could replace Christianity, Islam & JudaismIn Volume I, the book uses statistics and accurate prediction of actual events to confirm its doctrine, making it irrational to disbelieve. Just imagine, a religion in which--by all statistical standards--it's considered irrational to disbelieve. There is also a political system that is far superior to any of those currently used in the world. The final volume lays out a hypothesis that the Federal Reserve can use observation of the planet Mars to set interest rates, along with creating a new faith based currency to replace the US dollar in the event of its collapse.The book is called "The Mars 360 Religious and Social System" and is written by Anthony of Boston. It is on Amazon and can be previewed extensively for free. The hardcover version has a high quality color interior.
If it's based on astrology, that's all we need to know: it is guaranteed to be crap.
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1 hour ago, thewowsignal said:
Many decades of scientific research in the area of particle and quantum physics did not manage to bring this civilization to a higher level in terms of energy efficiency. There are many smaller and bigger labs around the world trying to make a scientific breakthrough. A small team of scientists following their own path, in my opinion, has better chances of making a significant scientific discovery. At least if they fail the financial 'damage' is not that big.
I know that many people will never agree to the above. To support my point of view please take a look at the LHC and how much it already costed. Do you think it is really worth the money already spent on it? Besides, a small team of scientific and enthusiastic nerds is worth more than thousands of people following the same way of thinking and waiting for a coffee break.
I think last couple of decades is the best argument to support my point of view. And scientific forums full of unanswered questions and weird theories make many young people doubt in trying to follow what is going on.Energy efficiency is not generally the goal of particle and quantum physicists, surely? Or do you mean those occupied with fusion research?
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1 hour ago, thewowsignal said:
Is there any alternative to nuclear energy? Long term, nuclear energy creates more problems than solutions. For many decades mankind has been trying to develop more efficient way of producing energy and tackle nuclear waste. Many scientific teams around the world hope to make some progress in this area. Billions of taxpayers money are being pumped into the research every year.
Is there any chance for nuclear fussion technology to power our homes and businesses in the near future? Is there any chance for nuclear power plants to become obsolete?I want to start a serious discussion here about our future on this small planet. This thread is especially dedicated to those of you, who are enthusiastic about atomic energy and energy crisis.
"Fussion" isn't a word. Do you mean fission or fusion? If you mean fusion, then I doubt it will make a contribution for another 30 years at least. But its long term potential is such that it justifies the current level of expenditure.
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52 minutes ago, TheVat said:
This made me burst out laughing, it is so crassly ignorant and incompetent. The laziness of pretending to be local and neighbourly, without even bothering to have a German sign off promotions referencing the local culture, is breathtaking. Some computer in the US seems to have been allowed to do it, unchecked, based on a calendar of anniversaries.
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1 minute ago, Externet said:
Thanks. "times" ?
"times" = "multiplied by".
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35 minutes ago, Sensei said:
https://www.google.com/search?q=noble+gas+discharge+tubes (and click Image mode)
On the right are pictures of various noble gases glowing in discharge tubes:
https://en.wikipedia.org/wiki/Noble_gas
If you want to verify this more rigorously, get a prism and split it into spectral lines.
ps. Your HV is not steady - build Cockcroft-Walton generator and/or Marx generator.
110/230 VAC -> DC -> high-frequency AC (timer 555?) -> CW generator -> discharge tube
Indeed. The orange-red in the video looks like neon, specifically. But obviously videos may not represent colours accurately.
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9 minutes ago, MacLeodNicholas said:
Thanks for this, I will look into it and try to do something with this information.
Good luck.
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8 hours ago, Axxel said:
Hi there!
I have few years still without any solution.
I could find just only one exemplary of this bulb or lamp there I share pictures, this is exactly what I need to know what it is, brand or datasheet.
The base is E27.
AND the most important, In this VIDEO you can see the lamp working: (I don't know is this usage is the correct usage, the lamp is powered with HV with only a single cable, it runs like a Plasma ball lamp) - Aparenlty these lamps are used to generate ozone.
Hope you can help me! I have YEARS with this issue... I never could resolve it...
Kindly Regards ;D
If you don't know what they are, from where do you get the information that they are used to generate ozone?
The video (which is very poor quality) seems to show a reddish glow. However ozone production by photolysis requires UV. So something doesn't seem to stack up here.
If the ozone information is wrong, then the red glow suggests to me it could be a neon discharge tube of some sort.
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2 hours ago, geordief said:
If any point in the spacetime model is specified wrt any reference point is it inevitably the case that that point can only ever be an approximation to any physical activity that actually takes place there?
If so is this because of theories like the Uncertainty Principle or does it simply follow from the spacetime model itself, because it models both position and time ,as well as (I imagine) that at the most detailed level that all things are in relative motion no matter how we try to set up any scenario that might illustrate processes at rest to each other?**
**Not completely sure if that is completely accurate and I think Studiot recently disagreed with Joigus as to whether "Panta Rhei" was as fundamental a proposition as I have always taken it to be.
No.
The uncertainty principle comes from QM, not relativity, and relates to non-commuting operators or, in the wave formalism, to certain pairs of properties being related to each other through Fourier transforms, whereby increasing precision in one leads to loss of precision in the other. QM is applied to physical systems - objects, if you like - rather than to spacetime.
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27 minutes ago, Scienc said:
I am a beginner in QE and I have a question. During I was reading about Output file, I saw a part where have it:
"The calculation goes on step by step until convergence is reached. Then we show all the energies of all bands (eigenvalues of the Kohn-Shan orbitals) for each k-point, the Fermi energy, the total energy, the contributions of all the terms to the total energy, and the calculation time used by each subroutine of the program."
Output file:
... iteration # 9 ecut= 100.00 Ry beta=0.70 Davidson diagonalization with overlap ethr = 1.00E-13, avg # of iterations = 1.0 negative rho (up, down): 1.151E-06 0.000E+00 total cpu time spent up to now is 28.4 secs End of self-consistent calculation k = 0.0000 0.0000 0.0000 ( 3909 PWs) bands (ev): -17.8569 -5.9595 -1.3957 -1.3957 4.4242 9.2594 9.9561 9.9561 k = 0.0000 0.0550 0.0000 ( 3909 PWs) bands (ev): -17.8034 -5.8955 -1.6155 -1.5115 4.4968 9.3266 9.9837 10.1886 ... -10.9411 -10.9411 -8.9101 1.6562 1.6562 12.4084 14.2298 14.2298 the Fermi energy is 1.6562 ev ! total energy = -22.80493136 Ry Harris-Foulkes estimate = -22.80493136 Ry estimated scf accuracy < 1.5E-15 Ry The total energy is the sum of the following terms: one-electron contribution = -44.02527202 Ry hartree contribution = 24.36506286 Ry xc contribution = -6.99363523 Ry ewald contribution = 3.85762303 Ry Dispersion Correction = -0.00870488 Ry smearing contrib. (-TS) = -0.00000512 Ry convergence has been achieved in 9 iterations Writing output data file grafeno.save init_run : 2.26s CPU 2.29s WALL ( 1 calls) electrons : 20.10s CPU 20.24s WALL ( 1 calls) ... Parallel routines fft_scatter : 4.35s CPU 4.44s WALL ( 23020 calls) PWSCF : 28.46s CPU 28.70s WALL This run was terminated on: 11:51: 0 5Sep2017 =------------------------------------------------------------------------------= JOB DONE. =------------------------------------------------------------------------------=I don't know the first thing about this program, but it sounds to me as if it may use some sort of method of iterative approximation that converges towards a final value. If that is so it may be programmed to stop iterating when the difference between successive iterations falls below a preset level, or something. Could that makes sense?
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1 hour ago, MigL said:
There are such things as 'rotons' and 'maxons', so I don't thinkhe's missing the 'P'.
They are theoretical constructs, useful in Bose-Einstein Condensate theory.See here Roton - Wikipedia
Yes, so I discover.
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38 minutes ago, 2dlayman said:
Do I understand correctly that ordinary rotons increase mass and extraordinary rotons decrease mass?
20 minutes ago, MigL said:Yes.
That's why I don't add croutons to my Caesar salad.( an excitation in superfluids may increase momentum, but not mass )
Rotons go very well with "p"s, I find.
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2 hours ago, Malle said:
I have no idea how to calculate the following task since I don't know the enzyme concentration - can someone help me?
I can't find a similar task to this - so I'm pretty lost.
The KM value for an enzyme is 20 mM. At a koncentration of 30 Mm, how much of the enzyme in percentage is bound to the substrate?
A) 40% B) 50% C) 33% D) 60%Well it's multiple choice, so all you need do is choose an answer that seems sensible.
What % of the enzyme is bound to the substrate at the Km value? You should know this from the definition of Km.
So then you can ask yourself whether the actual concentration of substrate is higher or lower than this - and choose an appropriate answer accordingly.
(At least, that is how it seems to me. Being a chemist, I didn't know what Km was, so I've had to to look it up. But I think I could now choose the correct answer.)
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3 hours ago, kenny1999 said:
I mean, fine scratch that you can probably find under light sources and you don't even feel it with your fingers. Are those fine scratches enough to harbor germs and bacteria?
I'm not talking about large scratches or cracks that I'll simply toss them without question.
Bacteria have a length of the order of 1 micron. The honing pattern in the cylinder liner of an engine, which is a pattern you can see but can't easily feel with your fingers, has grooves about a micron in depth. So if the scratches you are talking about are of this magnitude there will not be space for a colony of bacteria to hide in them. But as @Peterkinsays, there are some bacteria on all surfaces that have not just been sterilised and there will no doubt be a few in the scratches too. This is not a concern. The vast majority are not harmful and even for those that can be, our bodies are adapted to dealing with the sorts of low levels of them we are likely to encounter in daily life.
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Oxidative phosphorylation and hydrogen ions energy feasibility
in Biology
Posted
How can you be "back" if this is your first post?
I don't believe for a moment you are pitching this nonsense to investors next Friday, by the way.