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It might reduce drag when the aircraft is moving, but it's not going to provide lift for vertical takeoff.
The physics don't add up here. An aircraft achieves lift by directing air downward, with the two operative laws of physics being (1) F = m*a, and (2) every action has an equal and opposite reaction. The upward force on the aircraft equals the mass times the acceleration of the air directed downward. Directing air in a closed loop over and through the wing does not generate any lift.
I would guess the increase in fatalities is caused by the increased use of smartphones and distracted driving. The only two solutions I can see are mandatory technological measures to prevent a driver's phone from being used in a moving vehicle, or replacing the driver with self-driving or assisting-driving cars.
I see no genuine science in either of the two papers referenced by this article. Levi et. al.'s paper at best did a rough unvalidated estimate of the energy balance that cannot be considered reliable. Elforsk's paper contains nothing but speculative pseudo-science. I surprised you would publish this trash.
@yoatmon: The pyridine-functionalized carbon nanotube catalyst only work in an ALKALINE environment. Due to unsolved problems with membrane conductivity and durability, the only currently successful ALKALINE fuel cells run at high temperature and are fed pure hydrogen and pure oxygen, not air nor a carbon-based fuel like methane. So don't say goodbye to your platinum quite yet.
@Davemart: If you're interested in learning more, you'll have to do the leg work yourself.
Adsorption allows the same mass of gas to be stored at a lower pressure within the same volume tank
> Lower-pressure tanks are also safer, and they hold more fuel longer if there’s a puncture. I'm not so sure about this. A tank filled with gas plus carbon has a lot more flammable material that stays closer to the passengers for a longer period of time.
@Davemart: High pressure tanks must be manufactured as cylinders or spheres in order to minimize the tensile stress on the tank material. These shapes lead to "dead space" within the body of the car. Lower pressure tanks can be formed into arbitrary shapes that wrap around the other components inside the car, leading to less unused space inside the car body.
I would think it would be a lot easier, more reliable and cost effective to do the extra compression outside the cylinder, for example, in a supercharger with output pressure that can be varied by about 25%.
> it is safe, intuitive and enjoyable to drive, with no need for driver or passenger to wear a helmet. If it does not meet the federal crash standards for passenger vehicles (and I don't see how it possibly could), it would be classified as a motorcycle and in most states, the driver and passengers would be required to wear helmets.
To understand why no engine like this has ever been mass produced, simply look at the first image captioned "Drawing of the split-cycle TourEngine beta prototype". What they have drawn is the equivalent of a two cylinder engine (one power stroke per revolution). The engine is much larger and more complex than a standard V-Twin, and will therefore be heavier, more expensive, less reliable, and take up more space in the engine compartment. I doubt we will ever see this engine in production.
According to the study: "The key problem in applying CO2 flooding is the availability of a large quantity of CO2." That statement gave me a good chuckle. While the rest of the world is trying to figure out how to get rid of CO2, down in Texas, they can't figure out where to find it.
By my calculations, 84E12 CF gas = 86E15 BTU = 15E9 barrels of oil, which is in the same ballpark as our current oil reserves, and about 6% of the oil reserves in Saudi Arabia (according to the CIA World Factbook)
According to , the majority of the USA gets an annual average of 4-5 kWh/m3/day, or 25 billion BTU/acre/yr (1 acre = 4047 m3; 1 kWh = 3412 BTU; 365 days/yr). It is claimed the technology described above produces 25,000 gallons of ethanol per acre per year. At a LHV of 76,330 BTU/gallon (see ), that would give us 1.9 billion BTU/acre/yr. If we could use the ethanol with an efficiency of 35% (probably optimistic), that would give us a "field-to-wheel" efficiency of 2.7%. Do my calculations check out? If so, I think we might be able to do better with solar panels and batteries.
It astounds me that these companies are allowed to inject pretty much any chemical they want into the ground with no consequences.
Cost. Weight. Power consumption. This is a technology that is never going to be widely useful.
"per mile" is not a quantity intrinsic to the battery, and is therefore not useful for comparing two batteries. The second metric, $ per total MWh delivered over the lifetime of the battery is a more useful metric for all applications (EV, PHEV, HEV) although it makes some assumptions about what defines the battery life and those assumptions need to be both realistic and clearly stated for the metric to be useful.
My computations show a maximum theoretical thermodynamic efficiency of about 70% at an 18:1 compression ratio, with a power output of 260 J per cycle per liter displacement (swept volume), or about 26 kW (35 hp) per liter at 6000 rpm, assuming internal temperatures are kept low enough that the engine does not produce high levels of NOx emissions. An actual brake efficiency of 55% at 38 kW (48 hp) per liter would probably be achievable in practice, which sounds close to the performance they are claiming.
Wrong. If the Jets win all the rest of their games, then we would need one more win in the division.
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The best outcome for us would probably be a Jets-Steelers tie. That would make it easier for us to secure the home field advantage throughout the playoff.s
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Not quite as elegant as Toyota's Hybrid Synergy Drive, but it looks different enough to not infringe Toyota's patents.
By adopting the Miller cycle...the thermal energy of the fuel is converted to kinetic energy much more efficiently than it is with regular 4-stroke cycle engines... I think it makes about a 2% difference in the best case. If it were really MUCH MORE efficient, then every engine would be designed to use it.
...the researchers were able to curtail the amount of platinum required by 80%, and hope to soon reduce it by another 10% There is a big difference between another 10% and another 10 percentage points. From the context, it is clear the researchers hope to achieve a total reduction of 90%. That sentence therefore needs to be written as either "hope to soon reduce it by another 10 percentage points", or "hope to soon reduce it by another 50%", or "hope to soon achieve 90%", all of which say the same thing, in contrast to "by another 10%", which means that the total reduction would only be ~82%.