Create Aerated Concrete Using Xanthan Gum And Dishwashing Liquid

To make aerated concrete, add a foam-forming agent and stir in a significant amount of air. This serves to make the concrete significantly lighter, better insulating, and more resilient to fire. Making it can however be a bit of an issue, often requiring ingredients that aren’t purchased at the average DIY store. This is where [NightHawkInLight]’s method seems rather promising, requiring effectively only xanthan gum and dishwashing detergent.

For the small-scale demonstration, 15 grams of the thickening agent xanthan gum is mixed with enough alcohol to create a slurry. To this 60 mL of the detergent and 1 liter of water is added and mixed until the xanthan gum has absorbed all the moisture, which takes about 5-10 minutes. This mixture is then added to Portland cement with two parts cement to one part xanthan gum/detergent mixture and mixed for a while.

Of importance here is that this mixture will keep expanding in volume while mixing, so you have to have to keep an eye on the amount of air relative to concrete, as this will determine the strength and other properties of the final aerated concrete. If you continue past a certain point you will even create open-celled aerated concrete that’s completely porous, so you have to know what kind of concrete you want before you start mixing up a big batch.

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BigDog Throwing Cinder Blocks

bigdog-throwing-cinder-blocks

It’s as if giving cheetah-like speed to an advanced robot wasn’t good enough. The engineers over at Boston Dynamics must have been thinking to themselves, how can we make this thing even more menacing? The answer seems to be adding a highly dexterous articulated arm that gives the robot the ability to chuck objects as heavy as cinder blocks. We’re not kidding, look at the image above and you’ll see one mid-flight in the upper left. A quick search tells us that block probably weighs 30 pounds!

BigDog is a research project for the US military that we’ve seen navigating all kinds of terrain. It’s a heavy lifter able to carry loads where other machinery cannot. But now they’ve added an appendage that reminds us of an elephant’s trunk. It branches off of BigDog’s body where a quadruped’s neck would be. At the end of the appendage is a gripper that looks much like what you’d seen on industrial assembly robots. But enough talk, click through to see the action video. Oh, and if you didn’t pick up on the cheetah reference we made earlier you’ll want to check out this post.

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