Scientists find a use for old tea bags – turn them into roads

Paved with good tea

What to do with all the waste from preparing zillions of cups of tea? Researchers in Malaysia propose converting some of it into infrastructure.

Mohammad Al Biajawi at University Malaysia Pahang Al-Sultan Abdullah and his team outline both the problem and their plan to attack it: “The annual consumption of a country’s population of hundreds of tons of black tea results in considerable numbers of discarded teabags. These huge quantities are disposed in landfills… The aim of this study is to experimentally investigate the effect of [carbon nanotubes] from tea waste on the mechanical and fresh properties of cement mortars.”

They suggest how to best go about this, in a paper called “Investigation the effect of nanocarbon tube prepared from tea waste on microstructure and properties of cement mortar”, which was published in the journal Environmental Science and Pollution Research.

They ran tests that appear to predict good results: “incorporation of nanocarbon tube from tea waste into mortar resulted in a reduction in cement use, thus indirectly reducing CO₂ emissions and the greenhouse impact”.

They propose, as one of the main uses, incorporating the converted tea waste into “sub-bases for highway pavements and highway medians”. Doing that would, Feedback fears, tempt millions of tea drinkers to jolly themselves by declaring: “The road to [specify any location] is paved with used teabags.”

Solar blades

Electricity-producing solar cells could go the way – well, a way – of razor blades.

Layers of razor blades, rather than solitary blades, gave hairy-legged and hairy-faced people a more efficient way to get sunlight to interact with those legs and faces (benefitting those people by making their skin more clearly visible to admiring spectators). A great transformation happened several decades ago when double-blade, then triple-blade razors went on sale and quickly captured market share as well as hairs. Single-blade razors came to seem a bit passé.

Now, plans are a-print to create solar cells that have multiple layers. Under some schemes, each layer would be made of a different semiconducting material that would absorb its own, distinctive range of sunlight frequencies. Most solar cells, these days, are essentially just one layer, made of silicon.

Already, some solar cell designers use one or another variety of perovskite (a family of minerals), rather than silicon.

Perovskite-layering research has led to one of the most mildly-fun-to-try-to-say-out-loud titles ever to appear in a recent chemical journal.

The Journal of the American Chemical Society brings us the not-quite-mellifluous “La₂SrSc₂O₇: A-site cation disorder induces ferroelectricity in Ruddlesden–Popper layered perovskite oxide“, written by the slightly-more-mellifluously named, Japan-based septet of Wei Yi, Tatsushi Kawasaki, Yang Zhang, Hirofumi Akamatsu, Ryo Ota, Shuki Torii and Koji Fujita.

Individual alligators

Grown-up children, as well as young children, who like to impress their friends by making loud imitations of animal sounds can easily up their game – after they realise that alligators are individuals, not cookie-cutter soundalikes.

Every alligator, like every chimpanzee, cat, dog, crow or most kinds of large animal (every human, too!), makes its own, personally distinctive sounds. A study by Thomas Rejsenhus Jensen and colleagues at Lund University, Sweden, chats up the ubiquity and the power of this noisy individuality.

The study, in the journal Animal Behaviour, is called “Knowing a fellow by their bellow: Acoustic individuality in the bellows of the American alligator”. Co-author Stephan Reber made noise, so to speak, in 2020 when he and four other colleagues were awarded an Ig Nobel prize for inducing a female Chinese alligator to bellow in an airtight chamber filled with helium-enriched air.

Ants for arteries

The scourge of atherosclerosis, like many other medical scourges, might sometimes succumb to attack by dining. Dietary discipline could carry the cardiovascular system to victory, so to speak.

A study by Abdul Ademola Olaleye at Federal University Dutse in Nigeria and his colleagues highlights a health benefit of eating small bits of one kind of all-natural, but little-publicised foodstuff.

Details are in their study, “Analytical evaluation of fatty acid, phospholipid and sterol profiles of five species of edible insects: Lipid composition in five species of edible insects”, in the Pakistan Journal of Scientific and Industrial Research Series B: Biological Sciences.

Olaleye and his team focus especially on the ratio, in a food, of polyunsaturated fatty acids (PUFA) to saturated fatty acids (SFA). They analysed samples of ants gathered from several farms and markets. Their conclusion: “The PUFA/SFA ratios in the present study are good enough to discourage atherosclerosis tendency.”

Of all the discouraging news in the world, Feedback suggests this is the best kind.

Marc Abrahams created the Ig Nobel Prize ceremony and co-founded the magazine Annals of Improbable Research. Earlier, he worked on unusual ways to use computers. His website is improbable.com.

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