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User: pngai

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  1. Re:Should have gone with thorium on Cost Skyrockets For United States' Share of ITER Fusion Project · · Score: 1

    1. The LFTR fans think an inherently low breeding ratio is a good thing and always advertise "non-proliferating" as a feature.
    This of course makes the design very delicate (or unreliable if you like) in terms of neutron balance.
    It also makes the LFTR dependent on some external source of fissile material.

    2. and 3. are also true.

    4. is what worries me most. The cracks and corrosion are not a trivial problem and have never been shown to be solved.
    The presence of dissolved fission fragments means you are running a very complex chemistry experiment with your pipes and pumps.
    Most of our experience is with solid fuel where the fission fragments are well contained. It's going from one extreme (well controlled) to the other (worse possible case for fission fragment attack).

    Your 20 year time frame seems like a minimum to me. We need to add to that the time required to round up funding.

  2. Re:Should have gone with thorium on Cost Skyrockets For United States' Share of ITER Fusion Project · · Score: 1

    How many civilian LFTR anywhere?

  3. Re:Should have gone with thorium on Cost Skyrockets For United States' Share of ITER Fusion Project · · Score: 1

    Maybe GE thinks they're so smart their sodium reactors will never leak.
    Personally, I have my doubts.

  4. Re:Should have gone with thorium on Cost Skyrockets For United States' Share of ITER Fusion Project · · Score: 1

    Every sodium reactor ever run has had a leak.
    And a leak of radioactive molten sodium is always a serious leak.
    This makes the industry look very bad.

  5. Re:Should have gone with thorium on Cost Skyrockets For United States' Share of ITER Fusion Project · · Score: 1

    You could, and the Soviets did, use liquid lead as a coolant and neutron reflector.
    They powered their fastest submarines with them. There were a number of failures related to letting the lead cool off and solidify when the submarines were docked but adding some electric heaters for startup should solve that.

  6. Re:Should have gone with thorium on Cost Skyrockets For United States' Share of ITER Fusion Project · · Score: 1

    It's not clear an LFTR can run at temperatures suitable for a Brayton cycle.
    There are enough worries about corrosion without raising the temperature.

  7. Re:Um, right. on Don't Help Your Kids With Their Homework · · Score: 1

    That example involves breaking the problem down into smaller steps.
    Instead of subtracting 7 in one step, you do it in two steps, 5 and then 2.
    You subtract 5 first, as 15-5=10 is easy to remember.
    Then 10-2=8 is also easy to remember.

  8. Re:2x Lithium battery and cars still don't work on U.S. 5X Battery Research Sets Three Paths For Replacing Lithium · · Score: 1

    Did you include the cost of electricity?

  9. Re:Link to the NIF Status Update on Fusion Reactor Breaks Even · · Score: 1

    Worse yet, the energy to pump those lasers was much higher.
    The 1.8 megajoules of laser power were the output of pumping the lasers with 422 megajoules. And conversion from thermal to electric power is around 33% so there would need to be about 1266 megajoules of thermal power to produce that 8000 joules.

  10. Re:bbc? on Fusion Reactor Breaks Even · · Score: 1

    This is an inertial confinement system which means the lasers make it blow up.

  11. Re:Nuclear Bias on Japan Plans to Restart Most of Their Nuclear Reactors · · Score: 1

    Earthquakes are a symptom of built-up stress, a result of a continuing natural process (movement of tectonic plates). As you know from your choice of the word "induces", the boreholes are relieving stress which would otherwise be released later in a more violent way.

    This is a good thing.

  12. Re:I think I figured it out on New Process Takes Energy From Coal Without Burning It · · Score: 1

    CO2 is easily liquified at room temperature with moderate pressure. Once liquified, just open a valve at the bottom of the tank to drain out the liquid CO2, closing the valve afterwards.

  13. Re:Um, WHY? on New Process Takes Energy From Coal Without Burning It · · Score: 1

    I wonder how easy it is to separate the iron pellets from the coal ash at the scale of a large power plant, which is about one million pounds of coal per hour.

  14. Re:incapable of safely operating manned spacefligh on 71 Percent of U.S. See Humans On Mars By 2033 · · Score: 1

    Did you read the reports of the Accident Investigation Boards?

  15. incapable of safely operating manned spaceflight on 71 Percent of U.S. See Humans On Mars By 2033 · · Score: 1

    Challenger showed that NASA was incapable of safely operating manned spaceflight programs.
    Columbia showed that NASA was incapable of changing for the better.

  16. Re:Australia on Pepsi To Release New Breakfast Mountain Dew · · Score: 1

    So do you prefer sucrose? Because sucrose is a compound of (technically a disaccharide composed of the monosaccharides) Glucose and Fructose.

    As soon as it hits your stomach, gastric acidity converts sucrose to glucose and fructose during digestion.

  17. Re:I don't understand the "high cap" magazine ban on 3D Printable Ammo Clip Skirts New Proposed Gun Laws · · Score: 1

    You have confused "assault rifle" and "assault weapon".

    An "assault rifle" "is capable of firing more than one round when the trigger is pulled". Typically a burst of 3 or continuous fire.

    An "assault weapon" is defined by law as having some number of special features such as a pistol grip, flash hider, or bayonet mount or is simply on a list of "assault weapons" because of their looks.

    In CA, AW are defined by Roberti-Roos.

  18. Re:nothing new on Amazon Poised To Get Cut of CA Sales Taxes · · Score: 1

    Amazon will be building and operating large warehouses in these two cities. So there will be property taxes and other business taxes (inventory, utility?) as well as income tax on the workers and sales tax on the purchases made by the workers and property taxes on homes owned by the workers etc.

  19. Re:I have trouble seeing the point on Sidestepping Tactical Nuclear Weapons Limits With Strategic Bombs · · Score: 1

    And wikipedia says: The W80 is physically quite small, the "physics package" itself is about the size of a conventional Mk.81 250 pounds (110 kg) bomb, 11.8 inches (30 cm) in diameter and 31.4 inches (80 cm) long, and only slightly heavier at about 290 pounds (130 kg).

  20. Re:When will Americans demand change? on Heartland Security Breach Class Action: Victims $1925, Lawyers $600,000 · · Score: 1

    The average person couldn't pass an LSAT, doesn't understand deductive and inductive reasoning, yet you think they can make a useful contribution to the legal system? That would be like having people who don't know the difference between power and energy to design the power grid. Or someone who doesn't understand the difference between a pointer and data to write software. Etc.

  21. Re:This is _all_ class action lawsuits! on Heartland Security Breach Class Action: Victims $1925, Lawyers $600,000 · · Score: 1

    These people are too lazy or scared to sign a letter beginning the process of making an individual claim yet you somehow expect them to go to court on their own and make a case? Do you not see how contradictory this is?

  22. Re:CYA by the White House on Solar Power Is Booming — Why Do We Want To Kill It? · · Score: 1

    And Solyndra lost money on every panel they shipped. Not a sustainable business model.

  23. Re:THERE IS NO GEOTHERMAL on Japan's Damaged Reactor Has High Radiation, No Water · · Score: 1

    Fracking.

  24. Re:Copper Clad is NOT new on New Cable Designed To Deter Copper Thieves · · Score: 1

    GroundSmart Copper Clad Steel Cable is not a telecom cable. It is a ground cable, intended for direct burial without any insulating jacket. It does not carry signal or any power (normally). This is the kind of thing it is intended for: http://www.w8ji.com/ground_systems.htm

  25. Re:Asia goes up! on Apple Outsources A5 Chip Manufacture ... To Texas · · Score: 1

    You seem to be assuming that all of the money was spent locally but I suspect a lot of expensive machines in the fab were purchased from outside of Austin.