From mapping a continent to surveying the Universe

SIDING SPRING MOUNTAIN’ IS HOME TO OVER A DOZEN AUSTRALIAN AND INTERNATIONAL TELESCOPES. CREDIT: FRED KAMPHUES.
SIDING SPRING MOUNTAIN’ IS HOME TO OVER A DOZEN AUSTRALIAN AND INTERNATIONAL TELESCOPES. CREDIT: FRED KAMPHUES.

Australia’s first observatory was built on the shores of Sydney Harbour by Lieutenant William Dawes of the First Fleet, on the point where the southern pylon of the Sydney Harbour Bridge now stands. Optical astronomy was essential for maritime navigation, and for providing precise location measurements for surveying the new continent.

The country’s first major observatory was established in 1821 at Parramatta by Thomas Brisbane, Governor of New South Wales and, later, President of the Royal Society. The observatory was used to discover and record the galaxy NGC 5128—a now much-studied galaxy that radio astronomers know as Centaurus A, within which sits a super-massive black hole (see Recording the impact of a super-massive black hole). Continue reading From mapping a continent to surveying the Universe

Soaking up gases with molecular sponges

Absorbing carbon emissions from power stations and creating a new generation of hydrogen fuel tanks in future vehicles are just some of the potential applications of Dr Deanna D’Alessandro’s discoveries in basic chemistry.

She has created new, incredibly absorbent chemicals that can capture, store and release large volumes of gas.

It’s all to do with surface area, says Deanna, a postdoctoral research fellow in the School of Chemistry at The University of Sydney.

She has constructed crystals that are full of minute holes.

One teaspoon of the most effective of these compounds has the surface area of a rugby field.

What’s more, the size and shape of the pores can be customised and changed using light. So she believes she can generate molecular sponges that will mop up carbon dioxide, hydrogen, or in theory almost any gas—and then release it on cue.

In 2010, her achievements won her a $20,000 L’Oréal Australia For Women in Science Fellowship which provided equipment, travel support and a student to assist her.

Deanna’s compounds have similar molecular structures to those in seashells and the microscopic marine plants called diatoms.

These naturally-occurring materials are commonly used in toothpaste, laundry detergents, kitty litter and other industrial applications.

But her high tech equivalents are crystals known as metal-organic frameworks—clusters of charged metal atoms linked by carbon-based groups.

While she didn’t invent these frameworks, Deanna has developed new kinds of them which are more robust and possess the molecular pores that can be shaped by light.

Photo: Deanna D’Alessandro, The University of Sydney. Credit: L’Oréal Australia/SDP media

School of Chemistry, The University of Sydney, Deanna D’Alessandro, Tel: +61 2 9351 7392, deanna@chem.usyd.edu.au, scienceinpublic.com.au/loreal

Mopping up gases

Deanna D’Alessandro

University of Sydney

A sponge that filters hot air and captures carbon dioxide

Deanna D’Alessandro, The University of Sydney (credit: L’Oréal Australia/sdpmedia.com.au)
Deanna D’Alessandro, The University of Sydney (credit: L’Oréal Australia/sdpmedia.com.au)

We need better ways of capturing carbon dioxide emissions from power stations and industry. And we won’t be using hydrogen cars until we’ve developed practical ways of carrying enough hydrogen gas in the fuel tank. Deanna D’Alessandro’s understanding of basic chemistry has led her to create new, incredibly absorbent chemicals that could do both these jobs and much more.

It’s all to do with surface area. Working in California and in Sydney she has constructed crystals that are full of minute holes. One teaspoon of the most effective of her chemicals has the surface area of a rugby field. What’s more, the size and shape of the pores can be customised using light. So she believes she can create molecular sponges that will mop up carbon dioxide, hydrogen, or in theory almost any gas – and then release it on cue. Continue reading Mopping up gases