How The World Of Building Materials Is Responding To Climate Change

Source - https://www.vox.com/energy-and-environment/2020/1/15/21058051/climate-change-building-materials-mass-timber-cross-laminated-clt 

I will readily admit that I can't stand Science Friday.

I'm an NPR guy all the way, and I'm a science geek. Science Friday should be right up my alley. It's like they've made a show just to hook me in. (It's like Newton's Apple - which I loved as a kid - for the radio.)

And then Ira Flatow comes on and asks inane questions like, "what's your favorite cephalopod?" or "what does alligator poop smell like?" of serious scientists trying to discuss their research. If it weren't for Ira, I might really love Science Friday.

Occasionally, though, the topic is interesting enough that I fight through my Ira-loathing and stay tuned to WVXU (my local NPR station, I'm a sustaining member, doncha know).

In late February, for example, there was a segment (thirty-three minutes long) about mass timber buildings (buildings with wooden structural members) titled How the World of Building Materials is Responding to Climate Change.

Increasing concerns with steel and concrete construction - both release huge amounts of carbon dioxide during the material's initial production - are leading people back toward building with wood - or some form of engineered wood-based products (laminates, particle composites, etc) as a way to avoid the carbon dioxide release from concrete and steel production.

Not that the concrete industry isn't fighting back.

How N95 Masks Stop Viruses

Last week I lamented the fact that the 'what's in an N95 mask' didn't explain how the various layers actually stopped virus particles.

So I went out and found a video that did a better job of that.

Hopefully this video will help fill in some of the holes in your mask knowledge.

Holes and masks don't go together very well, doncha know?

What's Inside 3M N95 Respirator Masks? Find Out!

I, admittedly, haven't seen masks with exhaust valves in them yet. Interesting.

The video maker takes apart an N95 mask, exploring each level but apparently not looking into any research separately from what he sees under his microscope.

The first layer is polypropylene fibers, seemingly spun-bonded like Tyvek.

Then there's a thicker, rigid layer of also 'randomly' laid fibers. He doesn't tell us what that layer is made of. The layer is repeated.

He mentions - almost in passing - that the mask is electrostatically treated to help trap particles.

The final layer, the one against your face, is made of a mixture of small and large polypropylene fibers.

I do wish he went into a little more details of what the material in the middle layers is, how each layer contributes to the overall function of the mask, and how each layer's material is made. But, it's the best 'what's in an N95 mask' video I've found yet. Thanks to Material Science Girl for the tip on this video.

How a Former Rocket Scientist Makes the Best Copper Pots in America - Handmade

For some reason, I never would have thought of pots being handmade.

Knives? Sure...I've seen knife-making videos.

But copper pots always seemed like an industrial commodity to me, though I guess I understand that they must've been hand-made originally.

This video isn't necessarily about material science, but the use of three different metals to produce  single piece with different properties in each part would allow for a good wrap-up of a metals chapter.

The copper is a great conductor, so it's a great choice for the body of the cookware.

But copper is reactive, so the inside of the pot is coated in tin - a not terribly active metal with a lower melting point.

And a copper handle would be too hot too quickly, so the cast iron handle is riveted onto the copper body.

Apparently different metals have different properties. Who knew?

Sustainability: definition with simple natural science

I don't know why you'd need a fancy, French guy telling you what sustainable development is. It's development that can be sustained.

See, simple as can be.

Actually, the definition that Alex (sp?) gives - sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs - works really well. He does go on a bit to explain this in more scientific (thermodynamics, law of conservation of matter, photosynthesis) terms and to explore a few of the root causes of unsustainability.

The four causes of unsustainability...

• Relatively large flows of materials from the Earth's crust (mining, drilling)
• Accumulation of substances created by society (CO₂, polymers, trash)
• Physically inhibit nature's ability to run cycles (deforestation, paving over grass)
• Barriers to people meeting their basic needs worldwide (economic inequality)

The above video is posted on the Sustainability Illustrated website alongside a BUNCH of other videos. It's only an introduction to the topic, and his other videos go into much more detail on the topic.

The Chemarts Cookbook

From the ChemArts webpage, "[t]he CHEMARTS Cookbook offers both simple and more advanced ideas and recipes for hands-on experiments with wood-based materials. The book showcases interesting results, focusing on raw materials that are processed either chemically or mechanically from trees or other plants: cellulose fibres, micro- or nano-structured fibrils, cellulose derivatives, lignin, bark, and wood extractives."

ChemArts is a program at Aalto University in Finland pairing chemical engineering and art and design students to explore innovative uses for Finnish plant life (their words, from the video just below).



The program has published a 'cookbook' of sorts in which they provide recipes for 'cellulosic material exploration'. In other words, they have a bunch of recipes using cellulose derivatives from minimally processed materials like wood pulp to more processed ingredients like nanofibrillar cellulose, carboxymethyl cellulose, and microcrystalline cellulose along with fairly non-toxic materials like baking soda, calcium carbonate, glycerol, and starch.

The 'cookbook' is broken down with some basic science and ingredient background, methods and safety discussion, then the recipes themselves. The recipes are further classified as hard, soft, transparent, flexible, (3d) printed materials, colouring and dyeing, long fibres from nature, papermaking, and growing materials. The book then ends with some 'inspiration' projects that their students have made from the recipes in the book.

Some of the materials are going to require a bit of sourcing to manage, but the fact that they've published a recipe book for material science exploring sustainable, tree-based raw materials is spectacular.

The cookbook itself is available for €30.00 or as a free download pdf. You can check out some of the images from inside the 'cookbook' on this article (or they're all in the pdf.)

And, in case they make the free download disappear, I've uploaded the pdf to my Google Drive.

BORAX: What it is, how to use it, and how to cook it down PROPERLY

Wait for it...wait for it...

I promise you there's a punchline coming in this one, but it takes about 4:50 of set-up to get to the punchline.

What Trent (as previously featured) shows us here is the results of heating borax as a flux in blacksmithing of steel. He shows, initially, what happens when you pour borax straight onto heated steel. The borax bubbles up and doesn't necessarily stick right when it's been poured. Because of that, according to Trent anyway, some blacksmiths will 'cook down' their borax resulting in glassy beads (as previously featured) that can then be pulverized and used as a non-bubbling flux.

I get the feeling that Trent might not exactly see this as a necessary step.

The science of what's happening seems to be pretty straight forward

First off, borax is actually sodium borate (or maybe sodium tetraborate) decahydrate (Na₂B₄O₇·10 H₂O) (source).

Initially, the puffing seems to be from a simple loss of the water of hydration (the ·10 H₂O part of the formula).

Then the borax seems to decompose into sodium metaborate and boric anhydride through this reaction (source & source).

Na₂B₄O₇ ⟶ 2 NaBO₂ + B₂O₃ 

This appears to be the same reaction that causes the creation of the borax glass beads.

When the beads pick up colors, one source says that the color comes from the formation of metallic borate compounds such as Co(BO₂)₂. That's not relevant to this video, though.

Here we just get to have fun seeing Trent rant again.