physics

Andrew Ong

A new class of super-accurate atomic clocks may detect miniscule changes in the laws of physics and shed light on how and why life exists in the universe, Sydney physicists have found.

Andrew Ong and his collaborators at the University of New South Wales discovered that the clocks could detect potential changes in a fundamental constant that governs the interaction between electrically charged objects.

“A changing fine-structure constant could explain why the conditions of our universe are so finely-tuned for all life to exist,” says Andrew, who did the research as part of his PhD.

“The value of the certain physical constants have to fall within a narrow range in order for carbon to be produced in stars. Without this mechanism, there would be no building blocks for all carbon-based life on our planet,” he says.

Atomic clocks, which measure time via the frequency of atomic transitions, are about 100 times more accurate than existing clocks. They are used in GPS satellites and the definition of the standard second.

The researchers hope to measure the frequency change over a few years so they can collect enough data to reach a conclusion about whether the fundamental constants vary and the rate at which they might vary.

“If we could show that the physical laws are always changing, then we can say that life exists simply in the region of the universe where the conditions are just right,” Andrew says.

NSW State Finalist: Andrew Ong, University of New South Wales

Yaou Smets

Soccer ball-like molecules may help improve the performance of plastic solar cells, which could be used as the next-generation energy source, a Melbourne physicist says.

Yaou Smets, a PhD student at La Trobe University, and his colleagues from Australian Synchrotron and University of Kaiserslautern, Germany, used a small amount of fluorinated C60-buckyballs to understand the physics that governs the photovoltaic cell efficiency. This study was recently published in the journal Organic Electronics.

“One of the major drawbacks of the conventional silicon solar cell technology is that highly efficient cells are very expensive to produce. Therefore, as a cost-effective alternative, plastic solar cells have attracted extensive attention among scientists as a promising candidate to become the next generation photovoltaic devices,” says Yaou.

Scientists around the world are trying to find ways in which the electronic properties of the solar cells can be controlled and the cell efficiency increased. One of the key technologies is called doping, where dopants are introduced to the materials. Semiconducting or even insulating materials can be transformed into efficient conductors, which carry electrical current and enhance the cell efficiency.

“The molecule C60F48 is proven be the most effective dopant in its class, as only a very small amount of it is needed to initiate a considerable amount of free charge carriers in the semiconducting layers,” Yaou says.

Victoria State Finalist: Yaou Smets, La Trobe University


By travelling backwards it’s pushing knowledge forwards
All planets move around their stars in the same direction as the star spins—at least that’s what we thought.

But now Australian National University astronomer Dr Daniel Bayliss and his colleagues have found that some planets break the mould. [click to continue…]

…by putting the squeeze on mining waste

You may not be able to squeeze blood out of a stone but, by applying the right amount of ultrasound during processing, Jianhua (Jason) Du and colleagues from the Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE) have been able to squeeze a considerable amount of fresh water from mining waste. [click to continue…]

How do black holes eat?

8 June 2010

in 2010

Using galaxies as cosmic telescopes to reveal the diets of the black holes at the heart of every galaxy.

Anglo-Australian Observatory Astronomer David Floyd has been able to observe matter falling into a super-massive black hole – one of the Universe’s brightest objects. [click to continue…]

An international team of astronomers has discovered the oldest and most distant carbon in the Universe, but there’s not enough of it to support standard theories of how the Universe lit up, a member from Swinburne University of Technology has calculated.

In the early Universe a dark pervasive fog of neutral hydrogen gas lurked everywhere. Astronomers think that this fog cleared when the first stars formed and emitted light.

There is a close connection between the amount of light and carbon produced in stars. But adding up all the 13-billion-year-old carbon detected, Dr Emma Ryan-Weber and her collaborators came to the conclusion the amount of carbon, and therefore the number of massive stars, was insufficient to lift the fog. [click to continue…]

The odds that a futuristic quantum computer will be built of silicon have received a boost, thanks to new technology recently invented by researchers in the Centre for Quantum Computer Technology (CQCT). [click to continue…]

The first practical atom laser is a step closer today thanks to Australian researchers. [click to continue…]

Australian orchids are engaged in an arms race, using sensory overload to seduce male insects.

[click to continue…]

Little ripples, big swirl

16 August 2007

in 2007

How mini-earthquakes and tornados could one day be saving lives

Monash University engineer Leslie Yeo is using tiny earthquakes and tornados to assist the detection of biohazards and germ warfare. He and collaborator James Friend at the Micro/Nanophysics Research Laboratory hope to integrate their technology into an inexpensive, credit-card-sized sensor within five to ten years.

[click to continue…]

Fats trigger immune defence

14 August 2007

in 2007

Synchrotron light delivers Nature paper for young scientist

Natalie Borg and colleagues from Monash and Melbourne universities have shown for the first time how the body’s immune defence system can be triggered by fats, sugars and other biological compounds, not just by proteins. The research, published recently in Nature, opens the way to potential new treatments for whole areas of disease such as infections, rheumatoid arthritis, juvenile-onset diabetes and some types of cancer.

[click to continue…]

The cleaning power of sound waves on the back of a truck

A young researcher in Sydney is cleaning up contaminated soil by blasting it with ultrasound.

Andrea Sosa Pintos from CSIRO Industrial Physics has shown that toxic and carcinogenic pollutants, such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), can be decomposed quickly, easily and cheaply using a portable treatment unit.

 ”Chemical analysis of the soil and water after we’ve treated it confirms that more than 90 per cent of pollutants have been destroyed,” she says.

Present soil remediation techniques such as landfill disposal, incineration and bioremediation, have many limitations. “None of these provides a complete or cost-effective solution. And some of them can be time-consuming.” says Sosa Pintos.
“Our process is very simple. We generate high-power ultrasound waves in a slurry of the contaminated soil in water,” Sosa Pintos explains.

The soil and water are mixed and the slurry is pumped through a treatment unit where it is exposed to the ultrasonic waves. The whole process only takes a matter of minutes, as opposed to hours and days, or even months using other techniques.

 ”Ultrasonic waves travelling through the mixture create micro-bubbles. When these bubbles burst on the surface of the soil particles, they release intense shock waves which can generate temperatures of up to 5000 degrees Celsius. Any chemical contaminants on the surface of the soil particles bear the brunt of these bursts of energy and are blown apart,” she says.

Importantly, the surrounding liquid stays cool, eliminating the possibility that the remnants of the toxic compounds can recombine to form dangerous by-products, as sometimes happens using other technologies. Dioxins are formed during incineration, for instance.

The pilot plant Sosa Pintos and her colleagues have developed can already process about a tonne of soil a day. For a commercial scale system a more efficient feeder unit including a higher capacity pump would be required.

Sosa Pintos says. “If the right engineering company were interested, within a couple of years we could develop a commercial treatment unit able to be hauled to contaminated sites on the back of a truck.”

The combination of high destruction rates, very low energy costs, and the convenience of on-site treatment, makes high-power ultrasound a promising option for soil remediation. 

Andrea Sosa Pintos is one of 16 Fresh Scientists who are presenting their research to school students and the general public for the first time thanks to Fresh Science, a national program hosted by the Melbourne Museum and sponsored by the Federal and Victorian governments, New Scientist, The Australian and Quantum Communications Victoria.  One of the Fresh Scientists will win a trip to the UK courtesy of the British Council to present his or her work to the Royal Institution.

Surfing in Alice Springs

16 August 2006

in 2006

(before NT and SA collided two billion years ago)

TWO BILLION years ago, the Australia we know today existed only in pieces. Northern, western and central Australia all belonged to different continents. [click to continue…]

Research by a Perth forensic scientist is helping to
stem the flood of forgeries entering the international
antiques market.

A Perth forensic scientist is employing lasers to help trace pottery back to
the kiln site of its production, thus exposing ceramic forgeries, a multi-million
dollar criminal business.

Emma Bartle from the Centre for Forensic Science at the University of Western Australia has developed a scientific method to authenticate porcelain, based on a technique known as elemental fingerprinting originally used to establish where gold came from. It employs lasers to vaporise a minute amount of material, which can then be analysed for the elements it contains, and how much of each is present. The process causes no visual damage to the ceramics.

“Over the past decade a multi-million dollar industry has grown up in South-East Asia, Cambodia and Laos to forge Chinese Ming and Japanese Imari porcelain,” Bartle says. “These modern fakes are so detailed and sophisticated that gone are the days whereby trained experts can authenticate pieces using visual examination alone.

“By analysing the porcelains’ chemical composition we can establish the geographical origins of an artefact and trace it back to the kiln site of its production in China or Japan. Each site has a different combination of trace elements, such as strontium and lanthanum, which is unique.”

The accepted conventional method of authentication at present uses emitted radiation to estimate the age of the porcelain; the idea being the older the object the less likely it is to be a fake. However, the process causes visible damage to the ceramics, decreasing both their cultural and monetary value. “Even worse, forgers have now caught up with the science and are artificially aging their imitations”, Emma remarks.

Elemental fingerprinting, pioneered by Prof John Watling for establishing the provenance of gold, is now routinely used in forensic applications. However, its adaptation and application to ceramics is new.

This unique research has sparked both local and international interest. Already museums, auction houses and private collectors have come forward to loan items from their collections for analysis. “We are working in collaboration with The Percival David Foundation of Chinese Art (London), Bonhams Auction House (London) and the Kyushu Ceramics Museum (Japan).”

“We have also analysed some of the ceramic artefacts recovered from Dutch shipwrecks along the Western Australian coastline, which were kindly loaned by the Western Australian Maritime Museum. Private collectors from the US and UK have also sent porcelain shards from their own collections for us to investigate,” says Emma.

Emma Bartle is one of 16 Fresh Scientists who are presenting their research to school students and the general public for the first time thanks to Fresh Science, a national program hosted by the Melbourne Museum and sponsored by the Federal and Victorian governments, New Scientist, The Australian and Quantum Communications Victoria.  One of the Fresh Scientists will win a trip to the UK courtesy of the British Council to present his or her work to the Royal Institution.

Salads, shampoos and mining to benefit from theoretical
research into droplets

How much effort does it take to understand the behaviour of oil droplets?
A multi-disciplinary team of six researchers from the University of Melbourne
has spent the best part of two years, and used $300,000 of equipment to crack
the problem.

[click to continue…]

A new system for directing radiation to target cells has been developed in Melbourne. The new targeting system has the potential to specifically destroy cancer cells with minimal damage to healthy tissues.

The new targeting concept, for which an international patent is pending, uses a special class of radioactive atoms for which the radiation damage is confined to the molecules immediately adjacent to the radioactive atom.

The cell-killing effect is maximised by directing the radiation to the genetic material (DNA) of the target cell, with little effect on neighbouring cells.

“We expect that our targeting system will be particularly useful for small clusters of cancer cells, such as those that spread throughout the body when a cancer becomes more advanced,” says Dr Tom Karagiannis, research officer with the Peter MacCallum Cancer Centre where the system was devised.

Conventional cancer therapies such as surgery, radiotherapy and chemotherapy have resulted in a steady decline in cancer mortality rates over the years.  Only chemotherapy has the potential to be effective when the cancer has spread throughout the body, but often it is not effective.

Latest figures from the World Health Organization show that about 50 percent of cancer patients still die in developed countries and about 80 percent die in developing countries.

A unique feature of the cancer targeting system is the highly focussed damage caused by the radioactive isotopes used – most of the radiation damage is within a distance of only a few millionths of a millimetre.  This means they can kill cancer cells without causing significant damage to normal cells.

The new technology combines knowledge from a wide range of scientific disciplines, including radiation biology, chemistry and immunology, Dr Karagiannis says.  The key ingredient is a complex composite drug, made by attaching the radioactive atom to a DNA-binding molecule, which in turn is linked to a cancer-targeting protein such as an antibody.

“Our radiolabelled DNA-binding drug alone provided a very efficient ‘molecular bomb’ for destroying cells,” says Dr Karagiannis. “But it could not discriminate between cancer cells and healthy cells.”

To make a ‘smarter’ drug, researchers took advantage of the fact that many cancer cells express high levels of certain proteins on their cell surface. Antibodies that bind specifically to these surface proteins were used as vehicles to target the lethal damage to cancer cells.

“Our strategy builds on the growing interest in antibodies as cancer therapeutics,” says Associate Professor Roger Martin, Tom’s supervisor who has been working on the project concept for the past three decades.

“There are a currently only a handful of such anticancer-antibodies that have been approved for therapy and many others that are in clinical trials.”

Proof-of-principle studies with the new targeting system have yielded very promising results with cell cultures, but a commercial partner is required for further development.

Tom is one of 13 Fresh Scientists who are presenting their research to the public for the first time thanks to Fresh Science, a national program sponsored by the Federal and Victorian Governments. One of the Fresh Scientists will win a trip to the UK courtesy of the British Council to present his or her work to the Royal Institution.