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Tuesday, 4 May 2021

Of quartz – A colourful problem

Where does colour come from? Pigments, we say: the ability of certain materials to absorb and reflect different colours of light as electrons are excited along or within their structure. It’s true: sometimes we have to go as deep down as the chemistry, the connectivity between atoms, to see where colour comes from. Other times we don’t.

Structural colour arises from the nanostructure of materials: the arrangement of atoms in giant structures, or of groups of molecules. As they cluster together, they form planes, angles, surface details, and other interesting geometry with gaps and overlaps the same size as the wavelength of light. Like the colours seen on an oil slick, this structural colour happens when light interacts with the shape of matter.

Thursday, 22 April 2021

Going with the flow

Inkanoack (CC0 Public Domain via Pixabay)
Ice is often overlooked. A small fraction of water, hostaged on land – it’s even missed out on the water cycle provided by the national curriculum. However, as the climate changes, so do habitats, including icy ones. When the glaciers melt, less water is locked up as ice and more is available as freshwater for life. Researchers have been fascinated by this process and in particular the kind of new life that springs from glacial melts. Interestingly, however, as more water becomes available and the climate becomes more temperate, what is observed is a loss of biodiversity. Specialist organisms designed for living in harsh, cold, wintry environments die or are out-competed by more common species already found in neighbouring environments. The conclusion is that the unforgiving glaciers provide pockets for more unusual lifeforms to flourish.

Monday, 5 April 2021

A smart race

Nanorobot swarms are the stuff of sci-fi films, but smart dust is being developed now.

Johan Oomen.
An assembly of microelectromechanical systems or “MEMS”, smart dusts consist of a party of tiny robots that detect light, temperature, vibration, magnetism, or chemicals. They talk to each other via wireless network and employ radio-frequency sensors. Smart dust particles are just a few millimetres across – much like intelligent grains of rice. A dependent species, they have to operate together, like bees, ants, or other colony creatures. And they have their weaknesses too: smart dusts are vulnerable to microwaves, which could electromagnetically disable them.

Tuesday, 23 March 2021

Resistance

In 1929, Alexander Fleming published his first observations of penicillin under a microscope. A sloppy technician, he’d returned from holiday to find a fluffy, white mass growing on his staphylococcus culture – and decided to observe it. Through the microscope, he saw the penicillin inhibiting the staphylococcus, and postulated medical applications in his paper.
 
Public Domain via Nadya_il (Pixabay)

Wednesday, 10 March 2021

Performing dogs and molecular roulette

Performing dogs

 
Performing dogs take nerve-settling beta-blockers. Habj
How do we make new chemicals?

It was a question James Black asked himself in 1964 (or perhaps a bit before then), when he developed a new approach to molecular synthesis, and thus discovered propranolol hydrochloride – the compound that won him the 1988 Nobel Prize for Medicine.

An unexciting-looking chemical, it’s just two fused benzene rings and a side arm, but it’s been used to alter mood, easing aggression, phobias, and improving the social skills of people on the autism spectrum. It is used to treat PTSD, and commonly to ease performance anxiety amongst musicians and performing dogs.


Thursday, 25 February 2021

Discovery

Carbon nanotubes were known before bucky balls – discovered in 1985 by Harry Kroto, Richard Smalley and Robert Curl. Yet eight years later, in 1993, Nature published two independent papers recording the ‘new’ breakthrough discovery of rolled up graphene tubes forming close-ended pipes. How does this make sense?

The question of who ‘discovered’ carbon nanotubes is difficult to give a simple answer to. Like many material discoveries, there is more than one level of known and unknown. Although the debate over which individual deserves the title ‘discoverer of oxygen’ cannot be firmly settled, our choice of answer forms part of the foundation by which we understand the nature, concept and goals of science as a field. And don’t forget, recognition can be career-making.
 
Riichiro Saito, saito@mgm.mit.edu, rsaito@ee.uec.ac.jp

Tuesday, 16 February 2021

Listening to the Ocean

This is a guest blog post. The article was adaped with permissions from Sofar Ocean.

 
What has climate change done to oceans? And what do our oceans do for climate change?

For more years than we can count, oceans have helped us mitigate climate change, including the early effects of human greenhouse gas emissions. Acting as a giant carbon dioxide and heat absorber, or "sink", 90 percent of the warming that happened on Earth between 1971 and 2010 occurred in the ocean. Scientists think that gathering more and better data from the ocean and "listen" to what it has to tell us could be crucial to helping our mitigation efforts catch up to climate change.

Unsplash (CC0 Public Domain via Pixabay)

Wednesday, 10 February 2021

Counterfeit brandy

Szalony kucharz via Wikipedia Commons
In the 15th and 16th centuries, working out the alcohol percentage of wine was no easy feat. For ease, the authorities taxed alcohol according to volume rather than percentage, making importing gin a better deal than wine or beer. And so, naturally, the merchants looked for a loophole, and they found one – or so they thought: distil down the wines, and add the water back in after passing customs. It seemed foolproof. But they had not accounted for one thing: warming wine changes its chemistry. Volatile chemicals are lost, other chemicals – esters, acids, aldehydes – decompose, or undergo reactions. When the merchants rediluted their wine, it tasted different. Wrong. “brandewijn”, or “burnt wine”, they called it, and nowadays, we call it brandy.