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Converting Sunlight Into Liquid Fuel With a Bionic Leaf
hypnosec writes: Artificial leaf techology made waves the moment it was announced by Daniel Nocera back in 2011. His latest research, published in PNAS, involves gathering hydrogen from this artificial leaf, carbon dioxide from another source, and feeding it to Ralstonia eutropha bacteria to create liquid fuel. Once the materials are fed to the bacteria, "An enzyme takes the hydrogen back to protons and electrons, then combines them with carbon dioxide to replicate—making more cells. Next, ... new pathways in the bacterium are metabolically engineered to make isopropanol." Researchers say the same process could be used to make vitamins.
Honestly, how many stoners saw the phrase "Bionic leaf" and went "WOOHOO!" at the title before being very disappointment at the summary/article?
adjective
1.
utilizing electronic devices and mechanical parts to assist humans in performing difficult, dangerous, or intricate tasks, as by supplementing or duplicating parts of the body
I'm pretty sure this does not fit the definition of bionic.
The headline implies that we have a machine replicating the process of a plant. The summary indicates that what they have is a vat of bacteria that are making alcohol. Not nearly as attention grabbing, considering mankind has been using yeast & bacteria to make alcohols of various forms since the dawn of time.
If they have a more efficient process with simpler (cheaper) inputs, kudos to them. But this ain't no artificial leaf.
Isn't that nuclear fission? That must be one hell of an enzyme. I hope the terrorists don't get their hands on it!
...if they could change cucumbers into sunlight.
I've been working on it at the Academy for years. I'm close to a break trough, but I need more funding and a bit more time.
The Star Trek writers said, "how can we work the term "bedside manner" into this episode? There MUST be a way!"
When the shit dries, it can be used as fuel.
The energy balance doesn't work out here. Max solar intensity is 1 kw / m^2, or 1 kj per square meter every second, or 3.6 MJ per square meter per hour. A gallon of gasoline is 120 MJ. So assuming 100% efficiency and 100% peak sunlight, it would take 30 hours to make a gallon of gas from one square meter of artificial leaf. Considering the average solar intensity is about 10% the max, and any process involving the sun is max 20% efficient, it starts to take a very long time to make one gallon of gas. Not even including the energy requirements of the leaf / enzyme process.
For that, we'd need a fan...
When the shit dries, it can be used as fuel.
It can also be thrown all over the porch and doorstep of that asshole neighbor whose dog keeps crapping in your yard. In an area with leash laws.
Anti-GMO villagers with pitchforks will kill the project.
Leash laws only apply to owners of dog breed the public doesn't like.
The dog park by my house has leash laws. What that means is all dogs running off leash are fine and ignored. But if I show up with my pitbull who is trained better than any of their dogs and let him off leash the cops will arrive in roughly 5 minutes. The same cops will then *only* ticket me for being off leash while the other off-leash dogs continue to play in the park.
Leash laws are just lipservice to ban breeds people don't like from using the parks. No other dog breeds are required to follow leash laws.
Might as well just say that all Pitbulls, Rottweilers, and Dobermans must be leashed out of fear.
Be happy it is only that much. When I was in Denver they outlawed them entirely and sent animal control around to snatch any they find in a yard and put it down.
And it dries faster when you spread it out everywhere.
Sleep your way to a whiter smile...date a dentist!
Lots of dog owners don't have well trained dogs.
But being bitten by a chihuahua tends to be less damaging than being bitten by a pitbull/rottweiler/doberman. Plus it's a lot easier to discourage or stop a chihuahua from biting you in the first place. And probably easier to get the chihuahua to stop biting.
So fewer are likely to complain about dogs running off leash that they think are safe, than dogs they think pose a threat.
Yes it's racism.
So, it seems like we want to have as much CO2 in the atmosphere as possible to fuel this process. I, for one, am looking forward to the Diamond Age.
Leash laws only apply to owners of dog breed the public doesn't like.
The dog park by my house has leash laws. What that means is all dogs running off leash are fine and ignored. But if I show up with my pitbull who is trained better than any of their dogs and let him off leash the cops will arrive in roughly 5 minutes. The same cops will then *only* ticket me for being off leash while the other off-leash dogs continue to play in the park.
Leash laws are just lipservice to ban breeds people don't like from using the parks. No other dog breeds are required to follow leash laws.
Might as well just say that all Pitbulls, Rottweilers, and Dobermans must be leashed out of fear.
That's a risk you accept when you decide to own a breed that was primarily bred for the purpose of fighting.
An enzyme takes the hydrogen back to protons and electrons...
Isn't that nuclear fission?
No, it's chemistry. Specificially, ionization.
Monatomic hydrogen has a single proton (and very occasionally one or two neutrons) for its nucleus, "orbited" by a single electron. Molecular hydrogen has two atoms of hydrogen - two protons bound together into a molecule by sharing their associated electrons in a chemical bond.
Separating the individual nuclei from their chemical bonds (typically dragging along all but one or all but a few of their electrons) is a chemical process, producing a dissolved positive ion. Because hydrogen has a single proton and electon per atom, a positive ion of (non-heavy) hydrogen, missing one electron, is a bare proton.
Now if you wanted to change the number of protons and/or neutrons in the nucleus, change a proton to a neutron or vice-versa, or rearrange a multi-nucleon atom into or out of an excited state (say by adding or releasing a gamma ray), you WOULD be talking nuclear processes. If it cosisted of separating the nucleons of a single nucleus into two groups it would be nuclear fission. But separating the nuclei of different atoms from a molecular bond and/or removing electrons from them, is just chemistry. Energies per operation are measured in single-digit electron volts, rather than kilovolts or higher.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
well done, Daniel.