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Tags Fontus water bottles , indiegogo

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Old 21st April 2017, 07:17 PM   #81
arthwollipot
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Originally Posted by marplots View Post
Why don't we say this about other things? I need Vitamin C and the best way to get it is to eat Vitamin C. I need salt. The best way to get it is to eat salt.
This is quite true. The difference is that water is a lot more palatable than pure ascorbic acid or sodium chloride.

Originally Posted by marplots View Post
Generally we are not so focused and I submit the attitude in the US about drinking water has changed over the last few decades and is mostly not justified scientifically, but simply a fad. There's the ubiquitous bottle of water as an accessory people carry around. There's the glass of water the waitress brings you, usually without asking. Store shelves are full of various brands of water.

When I was a kid, we drank water when we were thirsty - from the tap.
Yep, I agree with all of this. The "8 glasses a day" thing was rubbish. You drink as much water as you need. And you can tell how much you need by monitoring the colour of your pee.

Originally Posted by marplots View Post
Alcohol yes, depending on the strength of the drink. Caffeine no, at least not for those acclimatized to drinking it.
Haven't heard that. Do you have a cite? I might need to modify my article.

Originally Posted by marplots View Post
Have you ever looked at how much water is in the normal foodstuffs you eat?

And then there's metabolic water (from Wiki):
"Metabolic water refers to water created inside a living organism through their metabolism, by oxidizing energy-containing substances in their food. Animal metabolism produces about 100 grams of water per 100 grams of fat, 42 grams of water per 100 g of protein and 60 grams of water per 100 g of carbohydrate."

I don't have anything against water, but it's not necessary to go out of your way to drink it or fear dehydration in the normal course of affairs.
Oh indeed. I never said it was or should be. Again, you can tell very easily how much water you need by looking at the colour of your urine. If it's dark, grab a quick glass. That's all there is to it.
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Old 21st April 2017, 07:38 PM   #82
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Originally Posted by arthwollipot View Post
Haven't heard that. Do you have a cite? I might need to modify my article.
Here's a decent overview: http://answers.webmd.com/answers/116...ine-a-diuretic

My understanding is that for regular caffeine consumers the amount of liquid water in the beverage more than matches any increased output. There's a parallel with low-alcohol beverages (although alcohol is recognized as a diuretic) where the volume of liquid consumed contributes to the urine output. Wasn't there a point in history where the usual beverage was not water (because of purification issues) but weak wine or beer?
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Old 21st April 2017, 07:45 PM   #83
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Originally Posted by LTC8K6 View Post
It seems like if there is enough moisture in the air for these devices to produce a useful amount of water, then you don't need the device because water is readily available. There is either a water source in the area, or it rains a lot in the area, or both.
The second product I linked to (not Fontus) supposedly works down to 20% humidity.

In some climates the difference between nighttime and daytime temperatures may give huge relative humidity swings, so an area generally recognized as arid or low-moisture, may still produce a morning dew. This makes "dew harvesting" a possibility: https://en.wikipedia.org/wiki/Air_we...ew_Utilization
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Old 21st April 2017, 07:56 PM   #84
arthwollipot
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Originally Posted by marplots View Post
Here's a decent overview: http://answers.webmd.com/answers/116...ine-a-diuretic

My understanding is that for regular caffeine consumers the amount of liquid water in the beverage more than matches any increased output. There's a parallel with low-alcohol beverages (although alcohol is recognized as a diuretic) where the volume of liquid consumed contributes to the urine output. Wasn't there a point in history where the usual beverage was not water (because of purification issues) but weak wine or beer?
Indeed, that's my understanding. It was safer to mix water with wine than to drink just the water. Diarrhoea dehydrates a lot faster than a weak alcoholic drink, and before modern medicine it was not unusual for people to die from it.

Thanks for the article, I'll check it out.
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Old 21st April 2017, 08:10 PM   #85
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Originally Posted by arthwollipot View Post
T...Again, you can tell very easily how much water you need by looking at the colour of your urine. If it's dark, grab a quick glass. That's all there is to it.
Actually, there seems to be quite a lot more to it than that.

Drink when you're thirsty is a good gauge, how often you need to urinate is a better gauge.

When working in extreme environments (cold, high or hot), we would use the whole urine color thing as an "advertising" reminder for workers to hydrate regularly. It is more of a meme than an accurate medical diagnosis.

ETA: I have not read your blog on the subject, so you may have covered the above.
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Old 21st April 2017, 11:16 PM   #86
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Originally Posted by EHocking View Post
Actually, there seems to be quite a lot more to it than that.

Drink when you're thirsty is a good gauge, how often you need to urinate is a better gauge.

When working in extreme environments (cold, high or hot), we would use the whole urine color thing as an "advertising" reminder for workers to hydrate regularly. It is more of a meme than an accurate medical diagnosis.

ETA: I have not read your blog on the subject, so you may have covered the above.
Yeah, I did, kind of, in different words.
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Old 22nd April 2017, 10:45 AM   #87
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Of interest:

http://science.sciencemag.org/conten...cience.aam8743

Quote:
Abstract
Atmospheric water is a resource equivalent to ~10% of all fresh water in lakes on Earth. However, an efficient process for capturing and delivering water from air, especially at low humidity levels (down to 20%), has not been developed. We report the design and demonstration of a device based on porous metal-organic framework-801 [Zr6O4(OH)4(fumarate)6] that captures water from the atmosphere at ambient conditions using low-grade heat from natural sunlight below one sun (1 kW per square meter). This device is capable of harvesting 2.8 liters of water per kilogram of MOF daily at relative humidity levels as low as 20%, and requires no additional input of energy.
Originally Posted by Hlafordlaes View Post
Since you fine engineers enjoy calculating, why not do one or more of the following and help a dude out, pretty please with sugar on top:

Determine:
- (optimal condensation temperature in equatorial regions, for a start)
- best type of continuous action compressor for this sort of tech
- max surface area of metal plating that could be cooled to optimal condensation
- optimum configuration of metal plating to compact surface area in small region
- optimum type of and configuration of metal plating for easy cleaning
- surface area of currently available solar panels to power one such compressor

Other:
- can sunlight be easily and practically filtered and mirrored as UV light? saves on another component for decontamination
- are ambient chemicals a danger when condensing air? say, next to a polluted river


***
Disclaimers:
I participated in an attempt to market and sell standalone Chinese-built atmospheric water generators in an African market (2009-10). We did not get funding.
By the end, I'd lost faith in the standalone concept (works, but is a 500 Watt machine).
I continue to speak with a HS friend from West Africa about how we might get some student engineers to work out the above issues and determine more about feasibility.

Short comment:
This may all be like the Apple Newton handheld that flopped decades before the iPad: that is, a question of waiting for component technologies to mature, especially solar panels. My non-engineer guess is that in all of this, it will be the cost of the energy used per liter that would make bottled water of this kind competitive or not in any given market. Note that there are countries with fecal matter in public water systems with the public importing large amounts of bottled water for cooking and drinking.

BBC World Service radio:

http://www.bbc.co.uk/programmes/p04rv3t9

Quote:
The Sun Water Solution
World Hacks

This is a story about how the most amazing ideas do not always work how you would like in practise. In theory it is so simple. You put disease-ridden water into a two litre plastic bottle, screw on the lid and leave it in the sun. After six hours on a cloudless day, almost all the bacteria and bugs that cause diseases like cholera and diarrhoea are killed or inactivated by the UV light and gentle warming. Professor Kevin McGuigan has proven this in the lab, but for the last 20 years he has been trying to get it working in rural African communities. It has not been anywhere near as easy as you might think.

(Photo: Godfrey putting his water bottle out to disinfect in the sunshine)

Same series:

http://www.bbc.co.uk/programmes/p04kxdjj

Quote:
Cloud Catchers In Peru
World Hacks

What can you do if you donít have access to running water? No pipes, no wells, no rainfall? The solution may be to catch water from fog.

We meet Abel Cruz, the Peruvian man behind a huge fog net project which is providing water to a community in the slums of Lima.

Could fog catching be a solution to wider water crises facing the world?

Also on World Hacks, we hear a big idea about giving soldiers weapons that do not kill.

Image caption: Fog nets in Peru / Image credit: BBC
Spoiler alert - yes contamination is a problem in - both pollution and biological, but it can still be useful.
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Old 22nd April 2017, 12:19 PM   #88
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Originally Posted by arthwollipot View Post
Without knowing anything about the details of the technology involved, my gut feeling is that if this works at all, it would do so way too slowly to be useful.
OK, air and light. Air contains water and light contains energy. So it is possible to extract water from air using light. In fact some substances can do it without added energy (but then you need to get the water out of the substance).

As you say, it is likely to be a low yield operation, and I can't help wondering what need exactly it proposes to fill (regardless of whether it works or not). The number of people lost in some desert desperate for a few mouthfuls of water is not much of a business proposition.

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Old 22nd April 2017, 01:03 PM   #89
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Originally Posted by arthwollipot View Post
This is quite true. The difference is that water is a lot more palatable than pure ascorbic acid or sodium chloride.
Not to everybody.

"Reminds me of my safari in Africa. Somebody forgot the corkscrew and for several days we had to live on nothing but food and water."
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