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Comment Re:P.E. is a joke. (Score 1) 18

4 Things About Obesity:
There's no exercise in P.E.
The more your parents force you to "eat right" the more obese you get - I can't find the link again but will hunt on request.
You can eat almost nothing but Big Macs and soda and be healthy.
Viruses might be at least partly responsible for obesity. One thing interesting is how quickly the paediatrician dismisses the study and gets back on the no-TV, soda, active lifestyle message. If it was going the other way, she'd not likely be criticising the small sample size.


Simple result. Obesity = Input Food - Output Exercise. It does not matter if you eat only Cheetos and Coke, or you eat organic food, if you exercise 400 minutes a day or 0. What matters is that you have equal amounts. You naturally have circuits that cause you to eat the right amount and to exercise the right amount. The problem is that parents force their children to eat whole plates of food at specified times, so they get more energy than they need. Next, parents and schools don't let them run around and fidget enough, so they don't get enough exercise. My parents, being wonderful that they are, did not do either. The result is that I eat maybe half as much as the average American, don't really exercise, but am not obese. I exercise not on a schedule, but when my body says so. I eat when I hungry - so I go to dinner at some random time, eat lunch randomly, snack, etc. A lot of energy is used to make food, and because I eat less, I'm green as a result ;).

Diet and exercise is like bleeding with leeches. Just today, I heard that a program was in place for diet and exercise to mitigate neuropathy, and virtually everything under the sun. Diet and exercise won't cure obesity, like it won't cure stomach ulcers, which are now known bacterial. The problem with diet and exercise is that if it fails, well obviously the answer is just more diet and exercise. Plus, it allows one to blame the patient if it fails, and to create a whole subculture of people who hate and discriminate against sick people. The fix for obesity will be to find a pill or other mod that lowers peoples' overfeeding tolerance. Then obesity will be gone for good. Or maybe we can just implant a fuel cell to eat up all the excess blood sugar. Either way, it's in the hands of bioengineers and scientists, not P.E teachers and the First Lady.

Comment Re:not new (Score 1) 50

Sundrop, AFAIK, is doing a solar-assisted biomass to liquids program. What they appear to be doing is gasification with:
CxHyOz + H2O -> CO2 + CO + H2O + H2

Instead of:
CxHyOz + O2 -> CO2 + CO + H2O + H2

So it's not thermochemical - it's biomass to liquids. But it's a heck of a lot more efficient than say, corn ethanol.

Comment Re:not new (Score 2) 50

Disclaimer: I work on this professionally, so I have a vested interest.

Cool. I'm a highschool student with a chemistry interest. Thermochemical engines were a subject I dug into a while back. I wrote a program using Gibbs free energy data from NIST to automatically balance and find the equilibrium constant of the reactions. I used this program to try to predict the outcomes of various reactions for cycle construction. I looked through the data and I found the following cycles to be interesting:
Fe2O3/Fe3O4
Sodium-manganese
Gaz de France (will explain)
Heat rechargeable batteries (will explain)

The Gaz de France (see slide show slide 26) runs as follows:
1. K2O2(l) + H2O(g) -> 2KOH(l) + O2(g) at 100 C
2. 2KOH(l) + 2K(g) -> 2K2O(l) + H2(g) at 725 C
3. 2K2O(l) -> 2K(g) + K2O2(l) at 850 C
Yes. That's potassium. All liquids and gases. No gas-gas separation. If this could really work, I'm sure there's a modification to it to produce elemental potassium. In that case, you can reduce mostly anything.

The idea with heat rechargeable batteries was as follows - using tin and iron as an example:
1. Fe + H2O + SnO -> Fe(OH)2 + Sn (aqueous battery - produces electrical current)
2. Sn + H2O -> SnO + H2 (corrosion of the tin - likely with heat)
3. Fe(OH)2 + H2 -> Fe + 2H2O

So it is an electrochemical heat engine. I know tin would likely make life more difficult by forming SnO2 but I left this out to illustrate the way the cycle works. You need two metals, call them A and B. A has to have as negative an electrode potential as possible but still be reducible by hydrogen. Iron fits the bill. Metal B has got to have as positive an electrode potential as possible but still be able to hydrolyze. Tin fits the bill. Copper would be better, but as far as I know, the reaction of copper with water to form hydrogen just does not proceed.

That said, I'm excited that if it's getting in the news, new or not, because it improves my odds of getting funding to use that tech.

Good. This tech needs a heck of a lot more funding. It's basically ignored - you read the news, you hear about EV's, fuel cells, solar panels, etc. But you almost never hear about thermochemical engines. The way I think about it, a solar panel is like a Ferrari. It's expensive and fun, but not a great way to cross Africa. A thermochemical engine is like a Toyota Landcruiser. It's durable, it's cheap, and it gets the job done. Have you heard of anyone getting VC funding for this thermochemical stuff?

Comment Re:Ideal Process Description (Score 1) 50

What on earth are you talking about? The process of thermochemical reduction is going to be:...

I understand you're reactions, but I'm giving the basic chemical equations, so I don't have O* on the surface, I have Ce2O3 + 1/2O <->2CeO2. I have the H2 and CO listed so that I don't repeat the reactions.

You have this thing going through methanol? Huh? These are all going to decrease your overall yield.

I have it going through methanol, because methanol synthesis and methanol to gasoline are (at least relatively) proven processes AFAIK. The claimed 50-60 percent is the maximum theoretical efficiency. I believe I've read a paper with 20% practical solar->hydrogen efficiency with zinczinc oxide. Maybe 20% is more reasonable.

Comment Ideal Process Description (Score 4, Informative) 50

Here's just a description of the reactions and why you want CO and gasoline. You want gasoline as the end product because gas is our infrastructure. You don't want methane, alcohol, or some other fuel, because conversion of vehicles to such fuels is virtually impossible with EPA regulations. Instead you want normal (though high octane) gasoline fuel.

What you get with this system is overall:
CO2 + H2O + heat -> gasoline + O2

The first step is to reduce CO2 and H2O:
Ce2O3 + CO2 -> 2CeO2 + CO (at low temperature)
Ce2O3 + H2O -> 2CeO2 + H2 (at low temperature)
4CeO2 + heat -> 2Ce2O3 + O2 (high temperature)

Next, it you don't have the right mixture of CO2 to H2O, you can do the following:
CO2 + H2 + heat <-> CO + H2O

Next, you create methanol:
CO + 2H2 -> H3COH

Finally, you create gasoline via the methanol to gasoline process:
H3COH -> gasoline + H2O

Now, where do you get the CO2? From CO2 traps, like soda lime:
CO2 + Mg(OH)2 -> MgCO3 + H2O (in alkaline solution)
MgCO3 + heat -> MgO + CO2 (heat)

You could power this CO2 trapper off of waste heat from the engine. This system could be up to 50-60 percent efficient at converting solar energy into gasoline. This is a vast improvement of biofuels, which are often less than 1% efficient. Gasoline engines are only 10% efficient, so the scheme is less efficient than electric cars + solar panels. However, the hydrogen and CO (especially) could be used as reducing agents to reduce metals such as iron and zinc. These metals would then be burned in metal-air fuel cells to provide power on demand. You also need hydrogen to produce ammonia and other industrial chemicals.

Comment Re:not new (Score 1) 50

All those cycles you've mentioned involve nasty chemicals, non-trivial separation or both. For example, one step in the sulfur iodine cycle is the conversion of sulfuric acid into its components:
H2SO4 -> H2O + SO2 + 1/2O2

The problem is that all these components are gasses, and they have to be separated as perfectly as possible (we don't want SOx in the air). So, as a result, a lot of expensive components are needed. With the sodium manganese, iron, and cerium cycles, you simply have to pump gasses away from the solids. The problem that occurs in these cycles is that the solids are powdered, and as they cycle through the system, the grains of the powder fuse together, reducing surface area, and thus reaction rate. Interestingly, this same process occurs in rechargeable batteries, and leads to their failure. Maybe robots can grind up the solids and increase their surface area?

In addition, in the sulfur iodine cycle, you've got SOx and I2 gases on the lose at high temperature. This can corrode the containers of the system.

My hope is that these thermochemical engines can crack aluminum and zinc oxides down to the metals. Then we can have engines reduce the metals, and use them in metal-air fuel cells. Metallic fuels are much cheaper and less of a hassle than hydrogen.
Image

8-Year-Olds Publish Scientific Bee Study Screenshot-sm 174

flintmecha writes "A group of British schoolchildren may be the youngest scientists ever to have their work published in a peer-reviewed journal. In a new paper in Biology Letters, children from Blackawton Primary School report that buff-tailed bumblebees can learn to recognize nourishing flowers based on colors and patterns. The paper itself is well worth reading. It's written entirely in the kids' voices, complete with sound effects (part of the Methods section is subtitled, ''the puzzle'duh duh duuuhhh') and figures drawn by hand in colored pencil."

Comment Re:But the engine upgrades are what make it fun... (Score 1) 183

Engine mods and upgrades are NOT fun. The reason is that it often costs upwards of $100,000 to certify any conversion kit for a vehicle with the EPA. What this means is that all alternative fuel mods on post 1975 vehicles are a no-go. Unless the fuel can go in without conversion (like with biodiesel), then the costs are going to be too high to make it viable. This is why CNG is not our primary transportation fuel right now.

Comment Re:Here is the stat that really matters (Score 1) 265

asshat compensating for his microscopic penis

Hey, you're just doing the same with your sanctimony. Anyway, if I get a SUV/Truck, I'll be happy. It'll probably biodiesel or biogas and it won't (much) emit CO2. Then, I'll be car free, like all the cool kids!

But at least I can agree with you about Windows.

Comment Re:Nice Sig... (Score 2) 270

Developed country population growth will not stop without closed borders, which is not politically fashionable. Developing country population growth will not stop without massive increases in wealth, which has real physical limits. Barring epidemics or massive warfare, how do you envision population growth stopping? Because nowhere on Earth is it stopping voluntarily.

This is the central flaw of Malthusianism. If you look at this graph, you'll see that population growth (births/woman) slows down as you get richer, with some noted exceptions in cases of religion. This means that wealth = no population growth.

There are clearly limits to wealth. The question is how big they are. History shows us that they are a lot bigger than we think. Here is the question. What would happen if everyone had a US style suburban home. The answer is that the only thing stopping it is energy. This is because our suburbs are powered by fossil fuels, not renewables. If we changed the equation and switched to renewables, 10 billion people could live in suburbia. 10 billion americans = 100 terawatts. The solar influx to the earth = 175,000 terrawatts. The prices of metals are all going down, meaning that they are getting less scarce.

"Innovation" currently goes almost exclusively into creating new consumer trinkets, healthcare and military applications which destroy wealth, increase lifespan and consumption, and create resource shortages.

A lot of innovation is going into producing the hated consumer trinkets, but much is going into renewables and finding new reserves of metals.

Comment Re:Counter Perspective (Score 1) 270

entirely new dooom-and-gloom scenario to get all worked up about.

That's the really scary scenario. Running out of doomsday scenarios. Seriously people, we could run out of things to be afraid of! The solution is recycling old, debunked doomsday scenarios to make new ones. Fortunately many people are trying to rectify the situation by ignoring the facts used to debunk old doomsday scenarios.

Comment Re:Nice Sig... (Score 4, Insightful) 270

So what will you call it when global production peaks?

A transition from oil to renewable energy. Oil production will peak from traditional sources, because renewable energy prices will crash through the floor, and production will soar.

What, iron? We have that. It isn't economically viable. And it will never produce enough liquid fuel to provide for the level of transportation we currently enjoy.

Then why does south africa use it for their diesel? Because it is.

You realize that coal will peak also, and isn't unlimited?

Because you can feed waste biomass into the system, like sewage, trash, and wood scrap. This already happening in Africa.

Population grows exponentially.

Paul Erlich, Tomas Malthus and the members of the flat earth society still believe this. The problem is that it is false, because captalism = wealth = less population growth. India, China, the USA, all have zero or rapidly zeroing population growth rate.

"Affluence" will peak once we reach the limit of exploitable resources on Earth.

Actually it will stop because people are starting to get satisfied with the amount of stuff they have. Once you have a house and an SUV, and maybe a motor home, what else do you want?

"Technology level" (whatever that means exactly) will peak given a large enough supply-shock to send researchers heading for the hills.

Because population growth will stop, innovation will stop the shortages, and wealth will grow, this just won't happen.

You do the math.

I did the math. Now let's see some math from the Malthus flat earth society, who's basic core fact (exponential population growth) is utterly wrong.

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