Posts about water

Clay Water Filters for Ghana

Pure Home Water, Ghana manufactures and distributes AfriClay Filters in an effort to bring clean water to 1 million people. So far they have delivered filters to provide 100,000 people clean water.

The process is simple. Water is placed in a clay filter and gravity pulls the water through the pores left in the clay during firing.

Sediment and bacteria are filtered out in several ways:

  • Physical straining: the particles are too large to fit through the pores in the clay
  • Sedimentation or adsorption: particles come to rest on or stick to the clay
  • Inertia: friction in the pores keeps the particles from passing through

Bacteria are also killed by a coating of colloidal silver (a disinfectant), which we apply to all filters that pass our quality control tests. While sediment and bacteria are filtered out, the molecules of water are small enough to pass through the pores in the clay.

The filters are sold to those who will use them. The effort has shown a willingness to pay by villagers in remote Northern Ghana (those earning < US$1/day). I imagine (I am just guessing) the prices are subsidized; in the last decade more (most?) appropriate technology solutions will have those benefiting pay something for the benefits they receive.

My nephews are working on a similar effort in India, using bio sand filters, I plan to post more on that later. There is current a campaign to help fund the delivery of water filters to Indian villages.

Related: Solar Powered Water Jug to Purify Drinking WaterElectric WindStudent Invents Solar-Powered FridgeReducing Poverty

Can You Effectively Burn Calories by Drinking Cold Water?

Neil deGrasse Tyson stated on Twitter:

Wanna lose 1200 Calories a month? Drink a liter of ice water a day. You burn the energy just raising the water to body temp.

What if your body is trying to cool down? I would imagine we have to use energy to cool off (though I am no expert on this)? So if you drink cold water and your body has less need to cool off, couldn’t this actually end up “saving” your body needing to burn calories – and thus cause yourself to gain weight?

This model would be similar to a server room that was cooled with air conditioning and cold winter air to cool off the servers. If there was less cold air used then more electricity would be used running the air conditioner to cool down the servers. I don’t know if it is a decent analogy though – maybe that isn’t an usable model for how we cool off.

I know we cool off partially by pushing water out onto the exterior of our skin to have it evaporate and cool us off. I would think that takes energy to do.

I do get that it takes energy to raise the temperature of the water you consume. It does make sense to me that if you were cold (like say I was during the winter living in the house I grew up in) you would use energy raising the temperature of the water.

What the overall energy situation is if your body needs to cool down seems questionable to me. Please let me know your thoughts. In any event his statement is accurate. It is just that the implication may lead people astray; that you can consume 1,200 Calories extra to balance the 1,200 Calories drinking cold water uses (or loss weight by having reduced your excess Calories by 1,200 if you eat exactly the same things you would without the cold water).

Related: Why is it Colder at Higher Elevations?Does Diet Soda Result in Weight Gain?Why Does Hair Turn Grey as We Age?How Corn Syrup Might Be Making Us FatWhy Wasn’t the Earth Covered in Ice 4 Billion Years Ago (When the Sun was Dimmer)

How to Walk on Ice

infographic explaining how to walk on ice - walk like a penguin

Infographic by Tablet. Falling on ice leads to many injuries and even 60 deaths a year in the USA (about the number that will die due to tornados). The graphic encourages thinking like a penguin. Penguins walk well on ice (in some ways) and they also fall well.

Seeking to keep your weight well supported (short strides) is wise (and sliding instead of picking up your feet can help). Falling well is also important. It is basic physics, you want to lower your center of gravity if you are start to slip and avoid any excessive force (so sliding is better than trying to stick out your hand and support all your weight). The elderly are especially susceptible to injuries – avoiding taking direct shocks to the wrist, knees or hips is wise). It does seem kind of silly to learn how to fall but it is very helpful in avoiding injuries.

On sidewalks if you are going to fall and there is snow piled up off the sidewalk, falling into the pile of snow may well be softer than falling directly onto the sidewalk.

On ice you have lower friction so strategies that require friction are not useful – quick moves often rely on very sturdy bases (which are based on the friction of our shoe on for example concrete [which normally is good - though business shoes are not very good] and on ice [where it is very poor - sliding and gradual moves are better]).

Related: Falling SafelyMinistry of Silly WalksMake Crosswalks More VisibleWhy Wasn’t the Earth Covered in Ice 4 Billion Years Ago – When the Sun was DimmerScience Toys You Can Make With Your Kids

Circumhorizontal Arcs – Fire Rainbows – Cloud Rainbows

photo of rainbow in a cloud

Fire Rainbow, Johor Bahru by John Hunter

Yesterday afternoon I spotted this odd, colorful, spectrum seemingly in a cloud in Johor Bahru, Malaysia. The colors are similar to a rainbow but the prism effect takes on a bit different form than a rainbow as I learned with a bit of searching online. I added a short post to this blog, about the phenomenon a few years ago.

photo of a large cloud over Johor Bahru

Johor Bahru under a large cloud which is topped with a fire rainbow.

A circumhorizontal arc is an optical phenomenon – an ice-halo formed by plate-shaped ice crystals in high level cirrus clouds. They are also known as “fire rainbows,” if the cloud is at the right angle to the sun, the crystals will refract the sunlight just as when rainbow is created.

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Solar Powered Water Jug to Purify Drinking Water

Deepika Kurup, a 14-year-old New York student, won the Discovery Education 3M Young Scientist Challenge for her invention of a solar-powered water jug that changes dirty water into purified drinking water. She won the top prize of $25,000.

During “the 5 minutes of my presentation 15 children have died from lack of clean drinking water.”

I am thankful we have kids like this to create solutions for us that will make the world a better place. We rely on hundreds of thousands of such people to use science and engineering methods to benefit society.

Related: Strawjet: Invention of the YearCheap Drinking Water From SeawaterWater and Electricity for AllThanksgiving, Appropriately (power of capitalism and people to provide long term increases in standards of living)

Sex and Development of Life in the Ocean

TED education is providing access to really interesting education material. In this webcast learn about fertilization, development and growth in the ocean depths.

Related: Hydromedusae, Siphonophora, Cnidarians, CtenophoresDarwin’s JellyfishThe Secret Life of PlanktonResearchers Explain How Rotifers Thrive Despite Forgoing Sex

The Secret Life of Plankton

Fun video with great shots of exotic ocean life that forms the base of the food chain in the ocean from TED Education.

Related: Hydromedusae, Siphonophora, Cnidarians, CtenophoresMilestones on the Voyage to the Bottom of the SeaMacropinna Microstoma: Fish with a Transparent Head

Underwater Pedestrian Bridge

photo of a 'bridge' parting the waters to allow pedestrian to pass

The Dutch water line was a series of water based defenses conceived by Maurice of Nassau in the early 17th century, and completed by his half brother Frederick Henry. Combined with natural bodies of water. The line could be used to protect the economic heartland of the Dutch Republic behind difficult to cross water barriers, when in danger.

The Fort de Roovere was part of this defense. In 2010 the fort was renovated and the moat revived with a small extra bit of engineering: a sunken pedestrian “bridge.” Where once engineers used ingenuity to use water to keep people out, now engineers used wood to let people experience the moat while still reaching the fort.

via: Sunken Pedestrian Bridge in the Netherlands Parts Moat Waters Like Moses!

Related: Monitor-Merrimac Memorial Bridge-TunnelMonkey BridgeQuantum Teleportation

Friday Fun: Octopus Walks on Land

Just a fun video for your Friday. Octopuses are really very cool. Not quite as cool as cats but way up there in the realm of cool animals. Octopuses, octopi and octopodes are all acceptable words for plural of octopus?

A few year ago (2008) I posted about another very cool octopus, who liked to juggling fellow aquarium occupants.

I think I will devote more time to learning about octopuses and posting more about them.

Related: Hydromedusae, Siphonophora, Cnidarians, CtenophoresCritter Cam: Sea Lion versus OctopusRed octopus at a brine lake beneath the sea

Student Engineers Without Borders Project: Learning While Making a Difference in Kenya

photo of workers digging a large hole dug for the bio-gas latrine, while schoolchildren look on.

Engineers Without Borders students make progress, learn lessons in Kenya

Knowing nothing about Third-World development, the original [Engineers Without Borders] EWB students accepted an assignment from the national EWB to bring clean water wells and sanitary latrines to 58 elementary schools in the poor Khwisero district, where villagers live by subsistence farming.

Each year, new MSU students take up the challenge, aiming not only to provide healthier drinking water but to relieve Kenyan children of the chore of hiking more than a mile to fetch water every day from dirty water holes, which cuts into their schooling, particularly for girls.

They finally broke ground on their first pipeline system, which has been three years in the making. It will bring piping water from a high-quality well to several villages and eventually to a health clinic and a market. Villagers have committed to digging trenches for the water pipes.

This is a great program. Students learn a great deal by taking on real world problems and implementing solutions. As I have said before, I really love to see appropriate technology solutions put in place. We can drastically improve people’s lives by helping put solutions in place that work, are cost effective and can be maintained. Improving people’s quality of life is at the core of why engineering is so wonderful.

Related: Smokeless Stove Saves LivesEngineering a Better World: Bike Corn-ShellerHigh School Inventor Teams @ MIT Bring Clean Water to VillageWater and Electricity for All
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Photo of Fish Using a Rock to Open a Clam

photo of a blackspot tuskfish using a rock to crack open a clam

Blackspot tuskfish using a rock to crack open a clam. Photo by Scott Gardner

Diver Snaps First Photo of Fish Using Tools

While exploring Australia’s Great Barrier Reef, professional diver Scott Gardner heard an odd cracking sound and swam over to investigate. What he found was a footlong blackspot tuskfish (Choerodon schoenleinii) holding a clam in its mouth and whacking it against a rock. Soon the shell gave way, and the fish gobbled up the bivalve, spat out the shell fragments, and swam off. Fortunately, Gardner had a camera handy and snapped what seem to be the first photographs of a wild fish using a tool.

Tool use, once thought to be the distinctive hallmark of human intelligence, has been identified in a wide variety of animals in recent decades…

There have also been a handful of reports of fish cracking open hard-shelled prey, such as bivalves and sea urchins, by banging them on rocks or coral, but there’s no photo or video evidence to back it up, according to Culum Brown, a behavioral ecologist at Macquarie University in Sydney, Australia, and a co-author of the present paper, to be published in a forthcoming issue of Coral Reefs.

The more we learn about animals the more tool use we find. It is continually interesting to see the wide variety of behavior documented.

Related: Bird Using Bait to FishDolphins Using Tools to HuntOrangutan Attempts to Fish with SpearAncient Chimps Used Stone “Hammers”

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