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Sarah Palin after the teleprompter freezes

newtboy says...

You are partially correct, I listed the rank of a top submarine officer incorrectly, but not his position, I'm not in the Navy. He was Executive Officer of the first nuclear sub, but only First Lieutenant of the diesel. EDIT: He "qualified for command" of the nuclear sub...probably why I thought "commander" but properly should have said "was in command". Shortly after being assigned to lead the nuclear sub trials, after helping design and build it, he led the American shut down of the Chalk River reactor, lest you continue to insinuate he was an 'armchair warrior' that never held command.
(record below)

◾17? DEC 1948 - 01 FEB 1951 -- Duty aboard USS Pomfret (SS-391) Billets Held: Communications Officer, Electronics Officer, Sonar Officer, Gunnery Officer, First Lieutenant, Electrical Officer, Supply Officer Qualifications: 4 Feb 1950 Qualified in Submarine


◾05 JUNE 1949 -- Promoted to Lieutenant (j.g.)


◾01 FEB 1951 - 10 NOV 1951 -- Duty with Shipbuilding and Naval Inspector of Ordnance, Groton, CT as prospective Engineering Officer of the USS K-1 during precommissioning fitting out of the submarine.


◾10 NOV 1951 - 16 OCT 1952 -- Duty aboard USS K-1(SSK-1) Billets Held: Executive Officer, Engineering Officer, Operations Officer, Gunnery Officer, Electronics Repair Officer Qualifications: Qualified for Command of Submarine Remarks: Submarine was new construction, first vessel of its class


◾01 JUNE 1952 -- Promoted to Lieutenant


◾16 OCT 1952 - 08 OCT 1953 -- Duty with US Atomic Energy Commission (Division of Reactor Development, Schenectady Operations Office) From 3 NOV 1952 to 1 MAR 1953 he served on temporary duty with Naval Reactors Branch, US Atomic Energy Commission, Washington, D.C. "assisting in the design and development of nuclear propulsion plants for naval vessels." From 1 MAR 1953 to 8 OCT 1953 he was under instruction to become an engineering officer for a nuclear power plant. He also assisted in setting up on-the-job training for the enlisted men being instructed in nuclear propulsion for the USS Seawolf (SSN575).


On December 12, 1952, an accident with the experimental NRX reactor at Atomic Energy of Canada's Chalk River Laboratories caused a partial meltdown. The resulting explosion caused millions of liters of radioactive water to flood the reactor building's basement, and the reactor's core was no longer usable.[7] Carter was ordered to Chalk River, joining other American and Canadian service personnel. He was the officer in charge of the U.S. team assisting in the shutdown of the Chalk River Nuclear Reactor.[8] The painstaking process required each team member, including Carter, to don protective gear, and be lowered individually into the reactor to disassemble it for minutes at a time. During and after his presidency, Carter indicated that his experience at Chalk River shaped his views on nuclear power and nuclear weapons, including his decision not to pursue completion of the neutron bomb.[9]

lantern53 said:

Just to correct a few fantasies here...Carter completed qualification to run a diesel sub, he was never the commander of a nuclear sub. He was never the captain of any ship, apparently, except the ship of state, which he proceeded to drive onto the sandbar of malaise.

The Fine Tuning of the Universe

StukaFox says...

"The idea that your cat is the Creator of the Universe has no explanatory power. To have an argument that your cat is the Creator you need to provide positive reasons for it. The Universe is finely tuned: if design is an explanation than I wouldn't need to disprove anything and everything as being a potential Creator, I would simply need to examine the evidence for design to make a determination as to what kind of being this must be, and using Occams razor I could come to some definite conclusions about it."

And I would posit that any same test applied to the Judeo-Christian god would fail the test equally (given that "god did it" isn't a theory, it's a construct). For that matter, so would any other god you want to throw out there. Assuming an intelligent creator pre-dating the universe created the universe calls into question "How did this dude himself go about getting created?". That question can only basically be answered with "It's turtles all the way down".

How do you know that a Universe governed by laws isn't the signature of a Creator?

How do you know my cat didn't create it? Equal empirical evidence (none) of both constructs.

Why would you expect to see a grand cosmos such as this, with such awesome beauty, whirling away with mechanical precision? The mere fact of its existence let alone its operation and stability is something too grandiose to be automatically regulated to some accident.

Really? We happen to live in a time period called the Stelliferous Era in which stars exist. Too far in the past, they couldn't form; too far in the future, they will no longer form. So oddly enough, given that the conditions are at this particular time are favorable to life, life came into being and evolved. So if it's your belief that god created this universe to be human friendly, why'd he wait so long for the conditions to be right for us to exist? Why not just do it on Day 1? Or why didn't he wait longer? Why did the universe have to be human-friendly in the first place? He's god -- he can do anything, so why are humans bound to all these rules of math, physics and chemistry, like every single other bit of life from bacteria to Blue whales?

How do you know that a Universe governed by laws isn't the signature of a Creator?

How do you know it's not my incredibly clever, and possibly deific, cat? Again, same empirical proof (none).

Why would you expect to see a grand cosmos such as this, with such awesome beauty, whirling away with mechanical precision?

We live in a time where the universe is able to support life. Outside of this neatly-ordered era, we'd be plasma or neutrons.

shinyblurry said:

You can prove a negative: there are no married bachelors. The idea that your cat is the Creator of the Universe has no explanatory power. To have an argument that your cat is the Creator you need to provide positive reasons for it. The Universe is finely tuned: if design is an explanation than I wouldn't need to disprove anything and everything as being a potential Creator, I would simply need to examine the evidence for design to make a determination as to what kind of being this must be, and using Occams razor I could come to some definite conclusions about it.

The second question is actually a really good one. I would expect to see the "signature" of the creator: something empirical that would point directly to a creator-being as opposed to a universe governed by. and explainable by, mathematical laws.

How do you know that a Universe governed by laws isn't the signature of a Creator? Why would you expect to see a grand cosmos such as this, with such awesome beauty, whirling away with mechanical precision? The mere fact of its existence let alone its operation and stability is something too grandiose to be automatically regulated to some accident. The intelligibility of the Universe is also something you seem to be taking from granted. Why should we even be able to comprehend it as far as we do? Could it be that the Creator gave us that ability?

I would also ask you why you think that understanding the mechanism somehow explains away agency?

Using Science to Explain Homeopathy ;)

gwiz665 says...

Neutron stars are bigger than bowling balls, and they ain't getting more squeezed.

I love it when crackpots get into scientific details, because they're so easily pulled apart.

Using Science to Explain Homeopathy ;)

lv_hunter (Member Profile)

siftbot says...

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This achievement has earned you your "Golden One" Level 6 Badge!

Neutron stars explained

lv_hunter (Member Profile)

Neutron stars explained

dannym3141 says...

Degeneracy is really, really cool. It's all about squashing things into as tight a region of space as you can. It's an observable justification of Heisenberg's uncertainty principle and the Pauli exclusion principle (the one that says you can accurately measure the position or the velocity of an object but not both and the one that says that two neutrons -in this case- can't both occupy the same very small region of space).

To be a neutron star, the remnant core after an unstable giant blows its outer layers away has to be more massive than 1.44 solar masses, but anything bigger than about 2.5 solar masses probably becomes a black hole. On the less massive end you get white dwarfs which are prevented from shrinking any more by electron degeneracy pressure - electrons won't let the star get any denser. But if you throw more mass on it, even electron degeneracy pressure can't resist the gravitational force and you get a neutron star, supported by neutron degeneracy - the neutrons won't let the star get any denser now. And then finally more and more mass and it becomes a black hole, which is where even the neutron degeneracy pressure can't sustain the gravitational force.

I mean, that's fucking cool - there is so much gravitational force that the electrons have to team up with the protons to become neutrons, because neutrons can get slightly closer together. And then if the neutrons aren't happy, you've got a singularity which is a fancy way of saying we don't know what the hell just happened but stay away from it if you like being in the part of the physical universe that kinda makes sense to us.

There's also speculation of a quark degeneracy state beyond neutron degeneracy.

Neutron stars explained

A First Drive - Google's Self-Driving Car

VoodooV says...

now all we gotta do is add neutron laser beams in the headlights and we can get all sorts of military funding to make this real.

pisses me off that we spend ungodly amounts of money on wars of choice instead of stuff like this.

We Can Dance - Hollywood Movie Dance Tribute

James Hansen on Nuclear power and Climate Change

GeeSussFreeK says...

I think that you will find enriched uranium is not plutonium. Also, depleted uranium can't be used to make nuclear weapons explode, so I don't know exactly why you bring it up. To be clear, all nuclear nations main weapons plutonium has been made in a very specific way, a way that is inconstant with power generation. It is exactly because power generation reactor are so costly that they are relatively poor weapons materials creators, the method in which uranium needs to be removed from the neutron flux requires you to shut it down often. It is better to get a small, non-power generation reactor and crank out the plutonium. This is what India did with a small test heavy water reactor (CIRUS reactor). You need a reactor you can quickly turn on and off (and uranium extracted), then chemically reprocess the uranium, let it cool down, then put it back into the reactor. This laborious method is why power generation reactors are poor candidates for weapons material generation and why the current generation of weapons have not been made this way.

IAEA safeguards are important to make sure enrichment centers aren't diverting enriched uranium, sure. Plutonium should also have some safeguards as well, so don't take my words for a lack of concern or action on a world stage, I just believe for most, their concerns are blown way out of proportion to the actual risk.

But to reiterate, the relatively complex process to make weapons ready plutonium is why powered reactors aren't used in for weapons material for any of the worlds nuclear weapons nations, nor have any of the non-nuclear nations which have nuclear power and participate in NPT and IAEA systems been implicated in such actions. If Amory Lovins is the one forming your opinion on this, I would suggest a different source. It is like asking the CATO institute their opinion on climate change. I would consult the IAEA or some respectable international organization known for objective science rather than an anti-nuclear advocate. I, actually, fell for the same supposed expert (Amory Lovins) and was fairly anti-nuclear myself as a result. While there surely is some overlap between weapons technology and reactors, they are separate enough that safeguards can be highly effective. The existence of many nuclear powered states without nuclear weapons gives credence to their abilities. Only those countries who decide not to participate in NPT and IAEA systems have been the players known to developing weapons, most notably North Korea.

IAEA Safeguards: Stemming the Spread of Nuclear Weapons

http://www.iaea.org/Publications/Factsheets/English/S1_Safeguards.pdf

I think he is pessimistic is because energy use is also in growth, usually from coal. When you similarly look at CO2 emissions over the past decade, they aren't going down...every year is a new record. Even in IEA's 450 Scenario, "oil, coal and natural gas — remain the dominant energy sources in 2035"...this is a problem.

I can't find a notable environmental group that endorsees nuclear at all. Like the public, most environmental NGOs don't really make a distinction in reactor types. Nuclear is nuclear is nuclear. From friends of the earth to greenpeace, they are all pretty proudly anti-nuclear, with only local chapters of FoE even remotely interested in revisiting their views.

At any rate, I hope you aren't finding me to be combative or argumentative, I am not the best communicator of controversial issues. But I think climate issues are forcing us into a pretty thick walled box which will be hard to breakout of even in the most optimistic technological factors, which is why even if every single concern people have about nuclear is completely justified, waste, weapons, ect, we would most likely still need to build lots and lots of nuclear to even hope to address climate issues...they are that challenging.

ghark said:

Reactors don't produce weapons grade plutonium? Then where is weapons grade plutonium made? I think you'll find that it's made in exactly the same reactors as there is no real distinction between a reactor used for power generation and weapons generation other than in name.

"Uranium ore contains only about 0.7% of the fissile isotope U235. In order to be suitable for use as a nuclear fuel for generating electricity it must be processed (by separation) to contain about 3% of U235 (this form is called Low Enriched Uranium - LEU). Weapons grade uranium has to be enriched to 90% of U235 (Highly Enriched Uranium or HEU), which can be done using the same enrichment equipment. There are about 38 working enrichment facilities in 16 countries"
http://www.cnduk.org/get-involved/parliamentary/item/579-the-links-between-nuclear-power-and-nuclear-weapons

The point is that continuation of current tech makes it a lot more economical to produce weapons tech, whether that be weapons grade plutonium or depleted uranium (DU). Reactors can cost upwards of ten billion dollars to build, why would a weapons manufacturer want to pay for one of those out of their own pocket when they can have the taxpayer's pay for nuclear power plants that can produce what they need?

"Every known route to bombs involves either nuclear power or materials and technology which are available, which exist in commerce, as a direct and essential consequence of nuclear power"
- Dr. Amory Lovins (from NEIS)

In terms of renewables:, the 'new' renewables only account for about 3% of total energy use, so if that's what he meant then he's not far off. Stats from IEA, however, state that wind has had an average growth rate of 25% over the past five years, while solar has averaged an annual growth rate of over 50% in the same period. So their impact is increasing fairly rapidly. So I'm not sure why he's so pessimistic about them when the IEA is not.

Have environmental groups specifically spoken out against the type of nuclear reactors he is talking about? Which ones?

ADSR Energy from Thorium

GeeSussFreeK says...

Reviving a super long dead convo, but it turns out you were WAAAY right. The reactor portion for these systems are still 99% critical, the accelerator is just providing a drastically small portion of neutrons. The less it provides the better return on energy, because like you said, the accelerator isn't running for free. If proton beams become cheaper in both capital costs and energy demands, perhaps their neutrons would be easier to design for than via chain reaction via moderation methods, but I don't see that happening soon, if ever. This might be one of those neat, but dumb things

Spacedog79 said:

You are most probably right about using spallation, I hadn't considered that. Either way it seems rather a complex solution to a non-existent problem. I am aware that some of the technology needed to make the accelerators powerful enough is fairly recent, so they must consume a fair amount of juice.

NASA: We Found Water On Mercury and How it was Found

GeeSussFreeK says...

O by the by, neutrons decay in free-space, in other words, free neutrons are radioactive. With a decay time of less than 15 mins, it means 2 things: slow neutrons will be less detectable at distance because they decay, you still need to be relatively close to the source of neutrons to detect them regardless of speed. Neutrons are also the only form of radiation that will make things radioactive, meaning if you get to close and the bombardment is to intense , you can cause damage to your equipment via internal radiation of beta and gamma rays.

This is also why they use water in nuclear reactors, hydrogen, and in particular deuterium (hydrogen with a neutron) slow neutrons better than anything. Water is mostly hydrogen by mole, so it is a very good moderator, both light water (regular water) and heavy water (deuterium water).

What is happening in this particular case is known as nuclear spallation. When a high energy proton hits something like carbon or nitrogen, it will at times knock a proton or neutron loose. Those neutrons are moving at relativistic speeds in most cases, so on the flip side, when those neutrons bounce their way out back to space, if there is water in the way they get slowed way down...enough that they decay before they reach the detector.

This is the same exact effect that allows for carbon dating, sometimes, the high energy neutrons that come out via spallation will in turn knock out a proton from a nitrogen atom, it then becomes mildly radioactive carbon. This happens at a relatively predictable rate, and since the decay of carbon 14 is also predictable, dating is possible.

Science rant over

ReverendTed (Member Profile)

GeeSussFreeK says...

Safe nuclear refers to many different new gen4 reactor units that rely on passive safety instead of engineered safety. The real difference comes with a slight bit of understanding of how nuclear tech works now, and why that isn't optimal.

Let us first consider this, even with current nuclear technology, the amount of people that have died as a direct and indirect result of nuclear is very low per unit energy produced. The only rival is big hydro, even wind and solar have a great deal of risk compared to nuclear as we do it and have done it for years. The main difference is when a nuclear plant fails, everyone hears about it...but when a oil pipeline explodes and kills dozens, or solar panel installers fall off a roof or get electrocuted and dies...it just isn't as interesting.

Pound per pound nuclear is already statistically very safe, but that isn't really what we are talking about, we are talking about what makes them more unsafe compared to new nuclear techs. Well, that has to do with how normal nukes work. So, firstly, normal reactor tech uses solid fuel rods. It isn't a "metal" either, it is uranium dioxide, has the same physical characteristics as ceramic pots you buy in a store. When the fuel fissions, the uranium is transmuted into other, lighter, elements some of which are gases. Over time, these non-fissile elements damage the fuel rod to the point where it can no longer sustain fission and need to be replaced. At this point, they have only burned about 4% of the uranium content, but they are all "used up". So while there are some highly radioactive fission products contained in the fuel rods, the vast majority is just normal uranium, and that isn't very radioactive (you could eat it and not really suffer any radiation effects, now chemical toxicity is a different matter). The vast majority of nuclear waste, as a result of this way of burning uranium, generates huge volumes of waste products that aren't really waste products, just normal uranium.

But this isn't what makes light water reactors unsafe compared to other designs. It is all about the water. Normal reactors use water to both cool the core, extract the heat, and moderate the neutrons to sustain the fission reaction. Water boils at 100c which is far to low a temperature to run a thermal reactor on, you need much higher temps to get power. As a result, nuclear reactors use highly pressurized water to keep it liquid. The pressure is an amazingly high 2200psi or so! This is where the real problem comes in. If pressure is lost catastrophically, the chance to release radioactivity into the environment increases. This is further complicated by the lack of water then cooling the core. Without water, the fission chain reaction that generates the main source of heat in the reactor shuts down, however, the radioactive fission products contained in the fuel rods are very unstable and generate lots of heat. So much heat over time, they end up causing the rods to melt if they aren't supplied with water. This is the "melt down" you always hear about. If you start then spraying water on them after they melt down, it caries away some of those highly radioactive fission products with the steam. This is what happened in Chernobyl, there was also a human element that overdid all their safety equipment, but that just goes to show you the worst case.

The same thing didn't happen in Fukushima. What happened in Fukushima is that coolant was lost to the core and they started to melt down. The tubes which contain the uranium are made from zirconium. At high temps, water and zirconium react to form hydrogen gas. Now modern reactor buildings are designed to trap gases, usually steam, in the event of a reactor breach. In the case of hydrogen, that gas builds up till a spark of some kind happens and causes an explosion. These are the explosions that occurred at Fukushima. Both of the major failures and dangers of current reactors deal with the high pressure water; but water isn't needed to make a reactor run, just this type of reactor.

The fact that reactors have radioactive materials in them isn't really unsafe itself. What is unsafe is reactor designs that create a pressure to push that radioactivity into other areas. A electroplating plant, for example, uses concentrated acids along with high voltage electricity in their fabrication processes. It "sounds" dangerous, and it is in a certain sense, but it is a manageable danger that will most likely only have very localized effects in the event of a catastrophic event. This is due mainly to the fact that there are no forces driving those toxic chemical elements into the surrounding areas...they are just acid baths. The same goes for nuclear materials, they aren't more or less dangerus than gasoline (gas go boom!), if handled properly.

I think one of the best reactor designs in terms of both safety and efficiency are the molten salt reactors. They don't use water as a coolant, and as a result operate at normal preasures. The fuel and coolant is a liquid lithium, fluoride, and beryllium salt instead of water, and the initial fuel is thorium instead of uranium. Since it is a liquid instead of a solid, you can do all sorts of neat things with it, most notably, in case of an emergency, you can just dump all the fuel into a storage tank that is passively cooled then pump it back to the reactor once the issue is resolved. It is a safety feature that doesn't require much engineering, you are just using the ever constant force of gravity. This is what is known as passive safety, it isn't something you have to do, it is something that happens automatically. So in many cases, what they designed is a freeze plug that is being cooled. If that fails for any reason, and you desire a shutdown, the freeze plug melts and the entire contents of the reactor are drained into the tanks and fission stops (fission needs a certain geometry to happen).

So while the reactor will still be as dangerous as any other industrial machine would be...like a blast furnace, it wouldn't pose any threat to the surrounding area. This is boosted by the fact that even if you lost containment AND you had a ruptured emergency storage tank, these liquid salts solidify at temps below 400c, so while they are liquid in the reactor, they quickly solidify outside of it. And another great benefit is they are remarkably stable. Air and water don't really leach anything from them, fluoride and lithium are just so happy binding with things, they don't let go!

The fuel burn up is also really great. You burn up 90% of what you put in, and if you try hard, you can burn up to 99%. So, comparing them to "clean coal" doesn't really give new reactor tech its fair shake. The tech we use was actually sort of denounced by the person who made them, Alvin Weinberg, and he advocated the molten salt reactor instead. I could babble on about this for ages, but I think Kirk Sorensen explains that better than I could...hell most likely the bulk of what I said is said better by him



http://www.youtube.com/watch?v=N2vzotsvvkw

But the real question is why. Why use nuclear and not solar, for instance?

http://en.wikipedia.org/wiki/Energy_density

This is the answer. The power of the atom is a MILLION times more dense that fossil fuels...a million! It is a number that is beyond what we can normal grasp as people. Right now, current reactors harness less that 1% of that power because of their reactor design and fuel choice.

And unfortunately, renewables just cost to darn much for how much energy they contribute. In that, they also use WAY more resources to make per unit energy produced. So wind, for example, uses 10x more steal per unit energy contributed than other technologies. It is because renewables is more like energy farming.

http://videosift.com/video/TEDxWarwick-Physics-Constrain-Sustainable-Energy-Options


This is a really great video on that maths behind what makes renewables less than attractive for many countries. But to rap it up, finally, the real benefit is that cheap, clean power is what helps makes nations great. There is an inexorable link with access to energy and financial well being. Poor nations burn coal to try and bridge that gap, but that has a huge health toll. Renewables are way to costly for them per unit energy, they really need other answers. New nuclear could be just that, because it can be made nearly completely safe, very cheap to operate, and easier to manufacture (this means very cheap compared to today's reactors as they are basically huge pressure vessels). If you watch a couple of videos from Kirk and have more questions or problems, let me know, as you can see, I love talking about this stuff Sorry if I gabbed your ear off, but this is the stuff I am going back to school for because I do believe it will change the world. It is the closest thing to free energy we are going to get in the next 20 years.

In reply to this comment by ReverendTed:
Just stumbled onto your profile page and noticed an exchange you had with dag a few months back.
What constitutes "safe nuclear"? Is that a specific type or category of nuclear power?
Without context (which I'm sure I could obtain elsewise with a simple Google search, but I'd rather just ask), it sounds like "clean coal".



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