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  1. 08 Jun '18 19:55
    https://phys.org/news/2018-06-trials-next-generation-harvester-fresh-air.html
    "...
    the water harvester can extract drinkable water every day/night cycle at very low humidity and at low cost, making it ideal for people living in arid, water-starved areas of the world.
    ...
    It operates at ambient temperature with ambient sunlight, and with no additional energy input you can collect water in the desert.
    ...
    The trial in Scottsdale, where the relative humidity drops from a high of 40 percent at night to as low as 8 percent during the day, demonstrated that the harvester should be easy to scale up by simply adding more of the water absorber, a highly porous material called a metal-organic framework, or MOF. The researchers anticipate that with the current MOF (MOF-801), made from the expensive metal zirconium, they will ultimately be able to harvest about 200 milliliters (about 7 ounces) of water per kilogram (2.2 pounds) of MOF, or 3 ounces of water per pound.

    But Yaghi also reports that he has created a new MOF based on aluminum, called MOF-303, that is at least 150 times cheaper and captures twice as much water in lab tests. This will enable a new generation of harvesters producing more than 400 ml (3 cups) of water per day from a kilogram of MOF,

    metal-organic frameworks, which are solids with so many internal channels and holes that a sugar-cube-size MOF might have an internal surface area the size of six football fields. This surface area easily absorbs gases or liquids but, just as important, quickly releases them when heated. Various types of MOFs are already being tested as a way to pack more gas into the tanks of hydrogen-fueled vehicles, absorb carbon dioxide from smokestacks and store methane.
    ..."
  2. 08 Jun '18 20:55
    Originally posted by @humy
    https://phys.org/news/2018-06-trials-next-generation-harvester-fresh-air.html
    "...
    the water harvester can extract drinkable water every day/night cycle at very low humidity and at low cost, making it ideal for people living in arid, water-starved areas of the world.
    ...
    It operates at ambient temperature with ambient sunlight, and with no additional energ ...[text shortened]... nks of hydrogen-fueled vehicles, absorb carbon dioxide from smokestacks and store methane.
    ..."
    Pretty cool. If they have something that makes water150 times cheaper than the other thing, why're they reporting on the massively more expensive one?

    Speaking of hydrogen-fueled vehicles, we were supposed to all be driving them in the late 80s. Where are they?
  3. Subscriber FreakyKBH
    Acquired Taste...
    08 Jun '18 21:11
    Originally posted by @wildgrass
    Pretty cool. If they have something that makes water150 times cheaper than the other thing, why're they reporting on the massively more expensive one?

    Speaking of hydrogen-fueled vehicles, we were supposed to all be driving them in the late 80s. Where are they?
    Oil.
  4. Subscriber sonhouse
    Fast and Curious
    08 Jun '18 22:33 / 1 edit
    Originally posted by @wildgrass
    Pretty cool. If they have something that makes water150 times cheaper than the other thing, why're they reporting on the massively more expensive one?

    Speaking of hydrogen-fueled vehicles, we were supposed to all be driving them in the late 80s. Where are they?
    Back in the 80's there was no way to get even close to the mileage of gas or diesel engines, which got something like 300 odd miles depending on gas mileage and size of tank.

    The way they used H2 back then was a pressurized tank of H2 at say 4000 PSI and it worked for a few miles but then you stop.

    Now there are chemicals called Metalorganic matrixes holding ten times the amount of H2 as the old pressure tanks.

    Even that doesn't give you 300 miles of continuous driving.

    The only good thing about H2 is the filling stations would be similar to gas, a station looking a lot like a gas station with pumps looking a bit like gas pumps but pumping gas into a chemical matrix that can store and release with low amounts of heat to get the stuff out.

    The downside of all that is building an entire new infrastructure of H2 delivery stations, how many thousands of gas stations are there around the country?

    Probably 2 times that for H2.

    So it isn't as simple as just making an engine that burns H2 or a fuel cell that converts H2 and O2 into electricity, they could do either back in the day, they can do both more efficiently today but the idea is about the same.

    But no infrastructure means it all has to be built and that is a multi-trillion dollar deal. So no surprise we don't drive many H2 cars now.

    All that plus the difficult problem of generating H2 enough to power an entire transport system for a whole country with tens of millions of cars.

    If you have any suggestions on how we do that, someone will listen, maybe you can be the next H2 Bill Gates or Jeff Bezos.
  5. 10 Jun '18 16:07
    Originally posted by @sonhouse
    Back in the 80's there was no way to get even close to the mileage of gas or diesel engines, which got something like 300 odd miles depending on gas mileage and size of tank.

    The way they used H2 back then was a pressurized tank of H2 at say 4000 PSI and it worked for a few miles but then you stop.

    Now there are chemicals called Metalorganic matrixes ...[text shortened]... s on how we do that, someone will listen, maybe you can be the next H2 Bill Gates or Jeff Bezos.
    I don't think distribution is an issue if there is a demand. A year ago it was very difficult to find kombucha, but now it's in every single grocery store around the country. Amazon could deliver it to your house for free.
  6. Subscriber sonhouse
    Fast and Curious
    10 Jun '18 17:07
    Originally posted by @wildgrass
    I don't think distribution is an issue if there is a demand. A year ago it was very difficult to find kombucha, but now it's in every single grocery store around the country. Amazon could deliver it to your house for free.
    I hope you don't drink too much of the stuff, there are known cases of liver and kidney damage from that drink and not much in the way of good studies showing any benefits.
  7. 10 Jun '18 18:02 / 4 edits
    The totally unscientific and unverified health claims made for Kombucha are so extreme as to be completely absurd.
    Just see what I mean below;

    https://en.wikipedia.org/wiki/Kombucha
    "...It has been claimed that Kombucha teas cure asthma, cataracts, diabetes, diarrhea, gout, herpes, insomnia and rheumatism. They are purported to shrink the prostate and expand the libido, reverse grey hair, remove wrinkles, relieve haemorrhoids, lower hypertension, prevent cancer, and promote general well-being. .."

    The "promote general well-being" part is so vague as to be meaningless but, putting that to one side, WOW! If only HALF of all that was true I think I would definitely drink it. But, come on, what do you think are the chances of even merely half of all that being true? Totally absurd!
  8. 10 Jun '18 21:29
    Originally posted by @sonhouse
    I hope you don't drink too much of the stuff, there are known cases of liver and kidney damage from that drink and not much in the way of good studies showing any benefits.
    Citations please!

    I enjoy it for the taste, not for any therapeutic benefit. The ingredients are good too. I have heard anecdotally from people who say it improves digestion. Can't find any evidence it causes liver and kidney damage. Your assertions are provocative but insofar speculative.
  9. 12 Jun '18 12:45
    Originally posted by @humy
    https://phys.org/news/2018-06-trials-next-generation-harvester-fresh-air.html
    "...
    the water harvester can extract drinkable water every day/night cycle at very low humidity and at low cost, making it ideal for people living in arid, water-starved areas of the world.
    ...
    It operates at ambient temperature with ambient sunlight, and with no additional energ ...[text shortened]... nks of hydrogen-fueled vehicles, absorb carbon dioxide from smokestacks and store methane.
    ..."
    If the air was truly dry there would be no moisture in it to extract. You really should choose your words more carefully.
  10. 12 Jun '18 15:43 / 3 edits
    Originally posted by @metal-brain
    If the air was truly dry there would be no moisture in it to extract.
    Dry air in this context obviously meant air without liquid water and typically not at particularly high humidity.
    Water vapor isn't liquid water.
    Obviously, most people would in every English call air with some arbitrarily 'low' humidity and no droplets of liquid water as "dry air" (especially the often very hot dry air in a desert).
    For example;
    http://fleteliercolortheory.blogspot.com/2008/02/color-theory-7-atmospheric-perspective.html
    "...Even in the clear, dry air of a desert the atmosphere changes the appearance of distant objects.[/b]..."
    etc.
    You really shouldn't make yourself look stupid like this.
  11. Subscriber sonhouse
    Fast and Curious
    12 Jun '18 19:10
    Originally posted by @metal-brain
    If the air was truly dry there would be no moisture in it to extract. You really should choose your words more carefully.
    You should choose your battles wisely instead of nitpicking semantics.
  12. 12 Jun '18 21:26
    Originally posted by @humy
    Dry air in this context obviously meant air without liquid water and typically not at particularly high humidity.
    Water vapor isn't liquid water.
    Obviously, most people would in every English call air with some arbitrarily 'low' humidity and no droplets of liquid water as "dry air" (especially the often very hot dry air in a desert).
    For example;
    http://fl ...[text shortened]... nce of distant objects.
    ..."
    etc.
    You really shouldn't make yourself look stupid like this.[/b]
    I said moisture, not liquid water. Use the word I used instead of trying to mislead by interjecting terms I never used.

    It is impossible to extract water from dry air. Dry air has no humidity. If it did it would not be called dry air. Common sense.
  13. 12 Jun '18 21:28
    Originally posted by @sonhouse
    You should choose your battles wisely instead of nitpicking semantics.
    You mean like you and humy both did in just about every AGW related thread on this forum? You really should choose your hypocrisy wisely.
  14. 13 Jun '18 06:56
    Originally posted by @metal-brain
    I said moisture, not liquid water. .
    I said dry air, not none moisture air.
    When people speak of dry air, they don't mean it has zero humidity, moron.
  15. 13 Jun '18 07:05
    Originally posted by @humy
    I said dry air, not none moisture air.
    When people speak of dry air, they don't mean it has zero humidity, moron.
    What is your source of information?