I read slashdot for at least six months before I got my first account, then I lost the password and had to make a new account later. If only I knew then what I know now...
rational: RMS's choice of clothing has nothing to do with the content of his arguments. pragmatic: Dressing in certain ways can prevent distracting the less-than-rational members of the audience. asshole: Hello. My name is Inigo Montoya. Your attire insulted my father. Prepare to die."
and you're plain ignorant of philosophy if you claim with a straight face that our philosophies haven't moved on in thousands of years.
This is an understandable belief if you consider that many religious people believe that philosophy was solved 2000 years ago and anything different from the bible is regression, not progress.
The way I kept my math skills fresh was to invent new problems to solve. Also I would derive every new formula instead of just memorizing it. Some random examples off the top of my head:
Derive newton's method. Find the formula for the circle that passes through any three arbitrary points Derive all the trigonometric identity functions
you're normally not so interested in the radiation itself but rather in where it came from
Your DNA molecules couldn't care less about the finer points of the X-ray vs. gamma ray distinction. Macroscopic cross-section and energy are the only things that matter at that level.
Unless they originate from a nuclear field, they are still x-rays. Various particle accelerator sources of photons are high energy, but they are x-ray sources.
All I was trying to say is that this statement is only true for a certain set of definitions. In terms of the inherent properties of the photons there is no difference between x-ray and gamma radiation, unless you draw some arbitrary boundary based on energy.
I understand that the distinction is useful to somebody, in certain cases. But as far as I know the only distinguishing characteristic of a photon is its energy. Are you saying that an instrument could tell the difference between a cosmic ray @ 1 MeV and a fission gamma @ 1 MeV?
Unless they originate from a nuclear field, they are still x-rays
I've never heard that definition of gamma radiation before. By convention photons are usually classified by energy: radio, microwave, infrared, visible, ultraviolet, x-ray. But really, a photon is a photon. It is all "gamma radiation"
You want to cool the water just a little bit below the condensing point, so that your pumps to do not cause the water to boil again (rough on the impellers). Any cooling below the condensing point is waste, so you want to minimize it to a little as practical,
A common error is to forget that the boiling and condensing temperature are highly dependent on pressure. Inside a condenser, the temperature and flow rate of the cooling water will determine the condensing temperature and pressure of the steam.
Carnot's theorem is a formal statement of this fact: No engine operating between two heat reservoirs can be more efficient than a Carnot engine operating between the same reservoirs.
Your open-cycle system will never be more efficient than a carnot cycle at the same temperatures.
The cold side for the steam cycle is typically going to be slightly subcooled water, maybe at 200F.
. That's too hot for a typical condenser. Any sane condenser will operate at a vacuum. If you remove all the air, then pressure in the condenser will be governed by the temperature. Which you try to make as close to the temperature of your cooling water as possible. As you increase the amount of cooling water you pump into the condenser, you lower the temperature and pressure inside the condenser. At some point, the increase in the amount of energy needed to pump cooling water faster is greater than the savings due to increased efficiency
Every subsequent round is less efficient than the previous round, because the difference between the fluids keeps dropping every round. Every round captures a smaller fraction of a shrinking temperature difference.
Not to mention that you are neglecting the energy needed to move all these fluids through your infinite number of rounds.
A nuclear reaction can produce much higher temperatures than that. Finding a good medium, and a good way to contain/control the reaction is an engineering problem.
Yes, you can engineer reactors to produce steam at higher temperatures.
As the "spent" medium is hotter than fresh (and it always is), its heat could be used again in another cycle. And so on (assuming "endless" supply of fresh medium, which river provides), until the difference in temperatures make another cycle impractical. This is how efficiency can -- in theory -- be brought all the way up to 1 but not quite.
No, you can never beat Carnot efficiency for a given set of source/sink temperatures no matter if you have an infinite supply of river water, or an infinite number of rounds. The efficiency of the series you describe converges to the Carnot efficiency, not to 1.
Slashdot Mirror
I read slashdot for at least six months before I got my first account, then I lost the password and had to make a new account later. If only I knew then what I know now...
You must be new here
So it now has a scar on it's face, and carries a sword-gun?
rational: RMS's choice of clothing has nothing to do with the content of his arguments.
pragmatic: Dressing in certain ways can prevent distracting the less-than-rational members of the audience.
asshole: Hello. My name is Inigo Montoya. Your attire insulted my father. Prepare to die."
Win2K was part of a different product line. It was Windows NT version 4. With XP, the product lines were merged.
The way I kept my math skills fresh was to invent new problems to solve. Also I would derive every new formula instead of just memorizing it. Some random examples off the top of my head:
Derive newton's method.
Find the formula for the circle that passes through any three arbitrary points
Derive all the trigonometric identity functions
The Spamhaus project has a list of Russian Business Network addresses, for what it's worth.
I wonder if anyone has every found a remote exploit that will get past iptables -j DROP recently.
You replay doesn't answer the question I was trying to ask. Obviously you can distinguish between a gamma and a neutron, beta, alpha, positron, etc.
Do two gammas at the exact same energy have any way to distinguish them based on their origin?
I understand that the distinction is useful to somebody, in certain cases. But as far as I know the only distinguishing characteristic of a photon is its energy. Are you saying that an instrument could tell the difference between a cosmic ray @ 1 MeV and a fission gamma @ 1 MeV?
The Navy is working on something but if I told you then I'd have to kill you.
Sorry, there are several types of "water" in these systems...
The steam that drives your turbines is condensed, then is pumped back into your boiler. (secondary water)
The condenser is cooled by the river water.
You don't mix the secondary water and the river water, because the boilers require very pure water with a controlled chemistry.
Excessive cooling of the secondary water is a waste which must be minimized.
You want to cool the water just a little bit below the condensing point, so that your pumps to do not cause the water to boil again (rough on the impellers). Any cooling below the condensing point is waste, so you want to minimize it to a little as practical,
A common error is to forget that the boiling and condensing temperature are highly dependent on pressure. Inside a condenser, the temperature and flow rate of the cooling water will determine the condensing temperature and pressure of the steam.
Your open-cycle system will never be more efficient than a carnot cycle at the same temperatures.
Every subsequent round is less efficient than the previous round, because the difference between the fluids keeps dropping every round. Every round captures a smaller fraction of a shrinking temperature difference.
Not to mention that you are neglecting the energy needed to move all these fluids through your infinite number of rounds.