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1.Pebble Bed Modular Reactors:
http://en.wikipedia.org/wiki/PBMR]http: … /wiki/PBMR
, look the links bellow about the actual developments and projects done by US, Nederlands`, Russian and South African companies.
I agree that the PBR are the future of the fission power. They are very suitable to be produced en mass scale, and as standartized assembly power units to be agregated in space tech: energy source of NTRs , Zuppero`s ice-ships, for powering life support systems, factiries and metal working instalations in marsDirect-like programs...
But, the all PBR posts are off-topic. Where are the chinese in this business? I think - only as customers. Practically, all the expertise bellongs to "western" communities. Germans for example have decades long testing of this scheme. It proves OK.
2.Hydrogen economy
Hydrogen will never be used directly in its gaseous form of H2, because it may cause much bigger environmental damages via the inevitable leaks of millions of tonnes in the atmosphere during production, trasportation and storage, than the nowaday mass produced greenhouse gases. Note that H is enormous potential factor for ozone layer depletion. It is very usefull for production of ethanol ( not methanol - it is very poisonous and very volatile) as storage substance...
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But, the all PBR posts are off-topic. Where are the chinese in this business? I think - only as customers. Practically, all the expertise bellongs to "western" communities. Germans for example have decades long testing of this scheme. It proves OK.
Well, the Chinese had enough expertise to build one. They will be building full scale production models soon. They will be the main costumers for this technology, but the power plants that they consume will be produced indigenously.
The Chinese attempts to build conventional nuclear powered submarines have had a lot of problems. I wonder if they will try and use PBMRs to power their submarines instead.
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Figures I have seen quote the energy required for transportation by hydrogen cells to be around twice what we consume in electricity, which I assume is produced by the fairly inefficent low/mid temperature electrolosis. If we manage to take a bite out of our electrical consumption by conservation, which is not a totally unreasonable assumption, then it will be on the order of 2-3X.
There is an energy efficency loss by converting electricity into Hydrogen by cracking it, but this must be weighed against the practical concerns of lighter vehicles with longer ranges then battery powerd electric cars. As for storage, it is possible to store Hydrogen as a metal hydride powder, which would not leak readily or explode and would operate at only modest temperatures. Other possibilities include using Carbon Nanotubes as a hydrogen "sponge" which is being worked on. With advanced materials, Hydrogen gas tankage could even do the job, since the stuff is not as dangerous as the Hindenberg incident makes it out to be... You can stick a lit match into a tank of H2 and it will go out.
"Note that H is enormous potential factor for ozone layer depletion."
As for Hydrogen being the next Evil Human Ozone Eating Mother Earth Killing Doomsday Gas, I don't think that is anywhere near clearly substantiated. One or two theoretical papers does not a reason to abandon H2 make... The added energy loss by going the Alcohol route, both in making the stuff and lugging the dead weight of the hydrocarbons, is not a viable solution in the long run for a hydrogen economy. The gas must be used directly.
As for PBRs in submarines, I doubt it... PBRs aren't all that compact, and dealing with a Brayton cycle gas cooled reactor requires more plumbing. The whole pressurized water + fuel rod idea was invented specificly for submarines and small reactors.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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This is your China of today..... :bars:
This is your China going nuclear..... :band:
Any questions?
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I just read a cool article. Apparently the chinesse government is seriously looking into building a railgun up the side of one of their higher mountains capable of launching a spacecraft!
My question, is this possible? If all they need is heat sheild technology similar to our space shuttles, then why haven't we been doing this???
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We have studied it
The spaceliner 100 concept space plane would have been launched by this means. By use of a maglev it would have gained a lot of speed before it had to fully power so making for a decent ground based first stage.
Other concepts where the sling-a-tron which would have used a coiled platform to spin a vehicle around and around before shooting it up the barrel. This principle is similar to what a sling would do, If it worked for david!
Blastwave, this concept has a series of short barrel segments that detonate and so thrust the vehicle forward like out of a cannon barrel increasing speed each explosion. This destroys the launch system though.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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I think one of the problems was the need for super conducting electrical wires to get the magnetic field strength high enough to make it propel fast enough.
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Ok, thanks for the info guys. So why did we stop with this concept (or have we?) and what developments make the Chinesse think they can do it better? Do it at all?
Is this more pie-in-the-sky hype for their program?
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China has a lot of recent experience with Maglevs, In shanghai for instance they now have the largest working maglev train system. The design came from germany I think but with the chinese doing all the labour im sure they have learned a lot. Well with us getting closer and closer to room tempature super conduction if they take the long view they can learn how to do it now and when the required missing technology is brought along probably by the computer/electronics industry it wont take them long to get going. That is something we do not have much of in the west patience but it seems the chinese can play the waiting game.
Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.
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Important stirrings in China's space program....
http://www.spacedaily.com/2004/04091606 … dw5ur.html
Maybe I wasn't so off the wall talking about China's ability to put a lot of hardware into orbit or the Moon?
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Several posts have mentioned the possibility of nuclear war stopping China, I think a world wide pandemic is much more likely. It would certainly stop us as well.
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Important stirrings in China's space program....
http://www.spacedaily.com/2004/04091606 … dw5ur.html
Maybe I wasn't so off the wall talking about China's ability to put a lot of hardware into orbit or the Moon?
Oops... I made a separate topic about that... Me bad.
Yet more confusion on the boards...
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Actually a very important thing to do for discusion of just there capabilities. As for there power in space flight They are definately catching up with each sucessful flight. I will not be long before we are in a new space race out of pride from the past achievements from apollo if it is important enough for this Nation.
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Well once they have heavier launch vehicles (and cheap I might add) then you really have to wonder how long it will be before they take a shot at the Moon. All their current projections are based on the fact that they don't have the capasity to do a Moon shot. However, large rockets change all that....
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Once they do develope heavy lift capability, they could then move armies if they should chose to do so. So we should keep that in mind, if we think that they are a military threat. I would rather chose to think they will not be so.
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China is overused as an excuse for military build up now that the USSR is no more. They don't want war with us anymore than we want war with them. The money they are getting from the US is the primary catalyst for their economic growth right now. I don't see them wanting to harm their biggest buyer of cheap t-shirts.
Even Bush was careful not include China in his 'axis-of-evil' speech and for good reason.
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I would think that china may destroy itself in one way or another. The three gorges dam on the yangtze river will soon become a stangnant pond after its completion. Most of the nearby cities dump all of their waste in the river. Once there is a large enough buildup a terrorist attack would easily be able to destroy the dam killing millions with flooding and the millions more with the epedemic the waste water could cause.
Besides taking china out has anyone thought of merely joining with them. I realize that a competion could spur a quick development of many new technologies but it is also true that two heads are better than one. The world is against each other in many different ways. including politics, economics, and even terrorism. Why should we be against eachother on space. I personally think that the worlds space organizations working together toward a common goal would be much better than it is now.
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Don't underestimate the chinese people, government and culture. I wouldn't, china will obtain their goals within their timeframe. Amercia is focusing alot on terrorism and not on what and where the country is going, we are the one's stressing out, We keep building forward like the chinese and when the terrorism head pops up , we clean the floors, ( terminate the terrorists ) and move on.
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Don't underestimate the chinese people, government and culture. I wouldn't, china will obtain their goals within their timeframe. Amercia is focusing alot on terrorism and not on what and where the country is going, we are the one's stressing out, We keep building forward like the chinese and when the terrorism head pops up , we clean the floors, ( terminate the terrorists ) and move on.
I read the speech of A. Scharwzenegger that he had at the rep. convention in NY.
In that speech he said that in the 50-60 everyone said that the US should fear the soviets. But it didn't happen the soviets even died.
Also the USA economy would be surpassed by Germany and Japan in the 80ies. This also didn't happen.
So what makes China really more special then the Soviets, German and Japan?
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I think a terrorist attack in China is just waiting to happen. Why do I think that? Well the inland (west) of China has a lot of different peoples and cultures. Of which some are Islamic. I'm not saying that this is the receipt for a terrorist attack. But one very important aspect is that the Chinese government is dominated by the coastal Chinese people. The others are still kinda of backward/underdeveloped and don't have very much to say in the policies.
Basically China is like a smaller Russia.
So what can happen in Russia it can happen in China.
Waht? Tehr's a preveiw buottn?
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Once there is a large enough buildup a terrorist attack would easily be able to destroy the dam killing millions with flooding and the millions more with the epedemic the waste water could cause.
The three gorges dam is made of concrete that is more than 100 meters thick. It is designed to withstand an earthquake measuring 10 on the Richter scale. It would be very difficult to destroy it without using nukes.
So what makes China really more special then the Soviets, German and Japan?
China has 1.3 billion people. China's economy(using PPP measurement) is already larger than the economies of the Soviet Union, Germany, or Japan were at their peak, both as a percentage of the total world economy, and in comparison to the US economy. China currently has more industry than any other country, including the US. In fact, China probably has more industrial production right now than any country has ever had. China's economy is also expanding rapidly, and their technology is improving.
Basically China is like a smaller Russia.
No, China is much bigger than Russia, at least in terms of population.
I think a terrorist attack in China is just waiting to happen.
Yes, terrorism attacks can happen in China, but the Chinese will not go into a panic when attacked like the Americans do. When the Chinese are attacked by terrorists, they will say 'so what?' and shrug it off.
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I think a terrorist attack in China is just waiting to happen.
Yes, terrorism attacks can happen in China, but the Chinese will not go into a panic when attacked like the Americans do. When the Chinese are attacked by terrorists, they will say 'so what?' and shrug it off.
So from the CIA factbook Russia had in 2003, 143 782 338 people (about 144 million people).
And China has 1 298 847 624 (about 1.3 billion people)
So lets take the last major terrorist attack in Russia (the one in the Russian school) were about 400 people died.
400 people is ((400/143 782 338 )x100) 2,7819828607878110870613329434106e-4 % of the total Russian people.
Now say a similair scale attack would happen in China. This means that 3613 people would die. Which is not nothing.
Waht? Tehr's a preveiw buottn?
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Euler,
Yes, I agree, and even if the terrorists kill 1 million or even 10 million in china, that would unleash the world's largest land army, and if that happens all rules are off, and the islamic world, had their chance to spot the terrorism, china doesn't run on the social responsible rules that the american's run under.
Russia, will unleash its military on its problem with not mercy for those people, because the terrorist acts against their children.
I pity the islamic countries through the world, unless they come out a attack terrorism and the schools and infrastructure that aids them, they might find their whole country on the end of the sword.
I hope that china doesn't get attacked and leave the sleeping dragon alone. If the terrorists want to use fourth generation warfare rules then we should to, block commerce from states to the rest of the world because they harbour terrorists, or who don't work against terrorism.
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Euler,
Yes, I agree, and even if the terrorists kill 1 million or even 10 million in china, that would unleash the world's largest land army, and if that happens all rules are off, and the islamic world, had their chance to spot the terrorism, china doesn't run on the social responsible rules that the american's run under.
Russia, will unleash its military on its problem with not mercy for those people, because the terrorist acts against their children.
I pity the islamic countries through the world, unless they come out a attack terrorism and the schools and infrastructure that aids them, they might find their whole country on the end of the sword.
I hope that china doesn't get attacked and leave the sleeping dragon alone. If the terrorists want to use fourth generation warfare rules then we should to, block commerce from states to the rest of the world because they harbour terrorists, or who don't work against terrorism.
This was a part of my between the lines points.
Who are todays super powers?
For me they are, in random order and not in particular based on military power but on military potential.):
1. USA
2. China
3. Russia
4. Europe (EU)
At this moment Russia and the USA are fighting a war against terrorists. If China were forced to join this war, things may be very different. So if China has its own big attack which is possible then a lot of Chinese funds like now US funds will be diverted to other (military) goals. This will disrupt the Chinese economy.
Waht? Tehr's a preveiw buottn?
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The three gorges dam is made of concrete that is more than 100 meters thick. It is designed to withstand an earthquake measuring 10 on the Richter scale. It would be very difficult to destroy it without using nukes.
Just because it was built to withstand that doesn't mean that it could. Cracks were being found in the early stages of development and after they were repaired they reapeared larger. Also the dam is built directly under an active fault line.
Has anyone considered a union with china and other space agencies?
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Also the dam is built directly under an active fault line.
Yes, hence the reason why it is designed to survive an eathquake that is much stronger than the stronget earthquake in recorded history.
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