Future Materials and Australian Nanotechnology Alliance

In this Issue

  • Research News

    Rock cores go digital: Three years ago a group of scientists and major petroleum companies formed a research consortium called Digital Core to explore new ways of analysing oil-bearing rock samples. Today, Digital Core leads the world in measuring and modelling porous rock, and the backbone of the consortium is the Computed Tomography Facility that researchers at the ANU Department of Applied Mathematics built from the ground up.

  • Know your material

    Testing karabiners: Climbers hang on the results: A materials scientist at the University of Wollongong has been carrying out safety checks into karabiners, a vital piece of equipment which climbers and mountaineers entrust with their lives.

  • Tin Tacks

    Low cost earthquake-resistant housing: Specialist earth builder Peter Hickson has combined ‘cob’ construction, one the world's most ancient building techniques, with modern engineering methods to develop a prototype low-cost earthquake-resistant house. His model house, made of earth and bamboo, could provide a template for low-cost earthquake-resistant housing for millions of people around the world.

  • Sensational Materials

    The oldest lunar zircon: Four and a half billion years ago the Moon was covered in an ocean. But this wasn’t an ocean of water but of molten magma. Now scientists from the Curtin University of Technology have analysed a lunar sample brought back by the Apollo 17 mission in 1972 that formed from that magma ocean. They’ve found a zircon crystal in that sample and determined the age of that crystal. In so doing they’ve thrown new light on the Moon’s early history and of our own planet.

    Laser printers release dangerous particles: The identity and origin of tiny, potentially hazardous particles emitted from common laser printers have been revealed by a new study at Queensland University of Technology.

    Quokka comes alive: Australia has a new machine for probing the structure of materials at the nanoscale. It’s called the Quokka and it’s a state-of-the art small-angle neutron scattering instrument.

Event Calendar


From the Director

Working towards a better tomorrow

Carla Gerbo

What will the Australian economy look like in 50 years? This was the question posed at 2059 Australia, a recent event I attended. But rather than asking a group of futurists or economists, the panel at this event was made up of three scientists and a social scientist. They presented some fascinating insights.

The themes coming from the three scientists were strongly aligned. In 50 years from now Australia would still be at the forefront of developing world-leading innovations, but we will have learnt lessons on the commercialisation of this knowledge. Our focus as a community would be strongly focused on education and ensuring that our education standards were at the peak of international ratings rather than in the middle.

Queensland’s Chief Scientist, Professor Peter Andrews, was on the panel, and he stressed that the key to achieving world best education is the encouragement of our brightest minds to see value in a career in teaching. In Australia, students entering teacher education are within the top 75% range. By contrast, Singapore gets their top 10% of students entering the teaching discipline. By striving for similar levels of quality, Australia would be making an important investment in a critical future resource base - the brain industry.

Andrews’ also reminded the audience of Australia’s competitive advantage in tropical technologies ranging from health, agriculture, environment and even mining. With a large percentage of developing economies lying in the tropics, this will prove a valuable future advantage.

So, we need a stronger focus on education and health. But the ground is also set for a growth in materials science and this area will bring solutions to a wide range of areas including energy, environment and climate change. What is currently regarded as emerging technologies will prove veritable toolboxes of change down the line. For example, according to Professor Max Lu, Director of the ARC Centre of Excellence for Functional Nanomaterials (and another panellist) the enhancement of solar panels could make the current debate on emissions trading a thing of the past.

Lu’s commitment to nanotechnology has earned him worldwide acclaim, and his team’s ground-breaking work on high-efficiency miniature crystals could revolutionise the way we harvest and use solar energy. In so doing we are one step closer to the holy grail of cost-effective solar energy. His team has grown the world's first titanium oxide single crystals with large amounts of reactive surface. This is the key to high efficiency in devices used for solar energy conversion and hydrogen production. Titania nano-crystals are a promising material for cost-effective solar cells, hydrogen production from splitting water, and solar decontamination of pollutants.

Over the next 50 years the importance of nanotechnology and other materials sciences in providing solutions to the world’s energy, water and environmental problems cannot be underestimated. I’ve often spoken in this column that part of the economic solution will come about through the targeted commitment of R&D.

Spending on R&D is a crucial part of the solution to ensuring our generation and future generations enjoy an improved quality of life, but the first step needs to get back to fundamentals of education. If we want our children to be the worlds best they have to be inspired and educated by the brightest minds.

Max Lu concluded in his presentation by updating a Queensland catch cry - in line with the Smart State comes the Learning State.

World class education, world class minds, world class lifestyle. It’s all achievable in the next 50 years.

Carla Gerbo
National Co-Ordinator - Future Materials
Director & CEO - Australian Nanotechnology Alliance


Research News

Rock cores go digital

Analysing rock cores takes more than fancy X-ray equipment

Professor Mark Knackstedt holding a rock core. Digital Core has revolutionised our capacity to analyse complex rock structures

Three years ago a group of scientists and major petroleum companies formed a research consortium called Digital Core to explore new ways of analysing oil-bearing rock samples. Today, Digital Core leads the world in measuring and modelling porous rock, and the backbone of the consortium is the Computed Tomography Facility that researchers at the ANU Department of Applied Mathematics built from the ground up.

When it comes to tapping an oil or gas reservoir, the fine line between commercial success and failure often comes down to how well you understand the properties of the rocky matrix that contains the oil and gas. How much oil or gas is stored in the rock? How easily can that oil and gas be extracted? Is it possible to flush the oil and gas out by injecting some fluid into the porous rock (and if so, at what rate)? These are all important questions that can take enormous sums of money and large amounts of time to answer by studying rock cores extracted from potential reservoir sites.

Professor Mark Knackstedt, one of Digital Core’s founders and currently head of Applied Maths, has spent many years attempting to mathematically model complex materials and specifically oil-bearing rock. The work began in the early 1990’s by building three-dimensional models of rock structures using information from two-dimensional thin sections, a laborious and painstaking job. In 1998, while visiting the United States, he was shown three-dimensional tomographic images of road samples and became excited by the opportunity to directly image 3D structure in detail. Tomography is the process of taking many X-ray projections of a sample at different angles and stitching them together with software to create a three-dimensional image of the sample. It’s often referred to as CT or computed tomography.

“This was pretty impressive stuff,” says Professor Knackstedt. “I returned to Australia proposing that we do some tomographic imaging of rock ourselves; so, a group of us at Applied Maths including Stephen Hyde, Tim Senden and many others, put together a linkage proposal to build our own facility.

“The proposal got up and we then had to decide whether to buy an off-the-shelf system or build our own. Having several experimentalists (such as Arthur Sakellariou, Tim Sawkins and Tim Senden) in the department with experience at developing a variety of equipment we felt we could design something that was much better than anything we could purchase, so we set about building our own CT unit. Of course, there were many problems to solve in the process and it ended up taking around two and half years to build; much of this time was spent at a white board discussing the design of the facility.”

A CT model of a rock sample

But what Applied Maths came up with was one of the most powerful and flexible micro X-ray CT facilities in the world; a unit so impressive that similar units have since been made and sold to companies around the world. It’s described as ‘micro’ because it’s primarily designed to scan objects with length scales ranging from microns through to millimetres.

However, the researchers quickly realised that powerful hardware was only half the story. When you’re scanning complex rock structures (over multiple length scales simultaneously) you’re generating vast data sets; data sets so huge that you literally need a supercomputer to work with, manipulate and analyse them.

“In many ways it was fortunate that it took two and half years to build the physical equipment,” comments Professor Knackstedt.
“That’s because it took a long time to write software and to build the computational infrastructure to handle the sort of data that was being generated. Indeed, handling the enormous datasets is one of the biggest problems with tomography.

“In a sense, the jewel in crown of Digital Core is the work done by the computational people, particularly Adrian Sheppard, Rob Sok and Holger Averdunk who initiated the work. This group has expanded considerably and now includes over 12 postdoctoral and more senior fellows building a broad range of software tools to handle and work with this data in a timely fashion. And that’s something that we believe is missing from almost every other CT facility in the world working in this area.

“We’ve been working on how to do this type of analysis for nine years so we’re experts in the area of modelling rock cores. For example, we’ve developed a phase separation technique that allows you to differentiate phases based on X-ray density measurements. But it might not be density alone, I can look at local behaviour, I can look at gradients in the density to see if I’m near an interface, and we’re continually developing new software to extend this capacity.

“Recently there was a case where the fluid was very dense in a porous system; so you had air, a very dense fluid and grain. The very dense fluid near the edges gave a similar X-ray attenuation to the quartz rock. So, how can you accurately describe the fluid phase, even though it bleeds into the density values of one of the other phases? It’s all about developing intelligent algorithms so we can handle challenges like this. And this constant refinement means the process can’t be automated. The machine can never give you all the answers; it’s all about how you interpret what you find.

“And when you’re dealing with geological materials there’s an enormous range of structures you need to interpret. Iron rich materials, for example, are very attenuating, and lots of clays can be extremely porous; and all that is important to understanding the rock itself. So you can’t just take a one size fits all approach and push the button and expect it to work.

“About three years ago we knew that we had something that was quite unique globally, and we were getting extremely positive feedback from the petroleum sector. The oil and gas industry spends vast quantities on extracting rock cores from reservoirs and traditional methods of analysis take months to years. Our tomographic scanning and digital analysis only takes days and provides much more detailed information than was previously available.

“And so we formed Digital Core, a consortium consisting of a group from here at Applied Maths, a group of petroleum engineers from the University of NSW, and money and resources from 14 of the world’s major oil and gas companies.”

And Digital Core has proved an enormous success with oil companies obtaining precious intelligence on their cores while the university has received funding to refine and extend the tomographic analysis of rock and a range of other complex materials.

“Our research has extended way beyond just oil-bearing rock,” observes Professor Knackstedt. “For example, some of the methods we have developed on analysing porous rock has extended to research on bones and osteoporosis. We’re also developing applications that will be valuable to tissue engineering, foamed materials, fossils and a range of manufacturing materials.”

Digital Core partners are now considering how the consortium might develop in the coming years.

“The value of Digital Core’s expertise has now been conclusively demonstrated and the demand for our expertise is only growing,” says Professor Knackstedt. “It’ll be interesting to see where things go in the years to come.

More info: Mark.Knackstedt@anu.edu.au


Know your material

Testing karabiners - climbers hang on the results

Karabiners: a little loop of metal with a whole lot hanging on their performance

A materials scientist at the University of Wollongong has been carrying out safety checks into karabiners, a vital piece of equipment which climbers and mountaineers entrust with their lives.

UOW materials scientist Tom Schambron, now employed by BlueScope Steel Ltd, has been putting the climbing equipment known as karabiner to the test. A karabiner is an oblong metal ring, usually made from high strength aluminium, with a spring loaded gate used in mountaineering to attach ropes - they form the link between anchor points on the rock wall and the climbing rope.

Mr Schambron, a climber himself, carried out tests both statically and, as an innovation, dynamically. And his conclusion is that purely static experiments are not adequate assessments of the complex forces acting on the equipment.

He says the ‘ideal’ climbing karabiner should be as light, strong and easy to operate as possible but must not open unintentionally.

“Up to now there is still no karabiner that satisfies all these requirements and that is why different kinds of karabiner are used in climbing,” says Mr Schambron.

He says that karabiners with no safety lock were simpler to operate but they were also more prone to opening unintentionally while karabiners with a safety lock prevented unintended opening but were more awkward to operate. He recommends the use of karabiners with a steel wire gate as these are lighter and stiffer than conventional gates, which is why they are less likely to open upon loading.

Results of tests carried out with various karabiners to check their strength were recently published in the Journal of Sports Engineering.

Mr Schambron said that the international standard for climbing karabiners requires a minimum breaking load of 20 kN (kiloNewtons) but this value only has to be proved in a static tensile test. One kilonewton corresponds to about the weight of 100 kilograms.

“The load is applied significantly more slowly in such a test than would be the case in the event of a fall where it would be a question of dynamic forces,” he says.

Mr Schambron said mere static tensile tests significantly overestimate the strength of climbing karabiners, so consideration must be given to carrying out routine dynamic tests when developing new karabiners.

More info: thomas.schambron@alumni.ethz.ch.


Tin Tacks

Low cost earthquake-resistant housing

Peter Hickson at work on the test model

Specialist earth builder Peter Hickson has combined ‘cob’ construction, one the world's most ancient building techniques, with modern engineering methods to develop a prototype low-cost earthquake-resistant house. His model house, made of earth and bamboo, could provide a template for low-cost earthquake-resistant housing for millions of people around the world.

Mr Hickson, a guest researcher in the Faculty of Engineering and Information Technology at the University of Technology Sydney, has been using the university’s shake table to test a half-size model of his design. The work is in collaboration with the Head of School, Civil and Environmental Engineering, Professor Bijan Samali and final-year engineering students Luke Punzet and Jean-Michel Albert-Thernet in building and testing the model.

"Cob is a building material made from subsoil, straw and water," says Hickson. "Clay is the binder, sand, silt and gravel the fillers and straw the reinforcing. Lumps of earth and straw mixture (cobs) are melded into a monolithic structure. It has been used worldwide for thousands of years and was a traditional building technique popular in England."

Hickson's house introduces many new technologies, but what makes his system unique structurally is the addition of internal bamboo reinforcing and the use of structural diaphragms.

"I believe well designed bamboo reinforced cob is the answer to sustainable housing for anyone living in areas where seismic activity poses a threat to safety,” he says. “That's sustainable with all aspects of sustainability considered - spiritual/cultural, social/economic and ecological."

In December his half-size model house made of earth and bamboo was put to the test on the state-of-the-art UTS shake table, the only earthquake simulator of its kind in Australia.

The house upon which the model is based

The four tests were based on the El Salvador 2001 earthquake which measured 7.8 on the Richter scale. The first test was set at 100 per cent intensity, the second at 125 per cent intensity. The third and fourth tests represented the aftershocks that occur after the main earthquake hits and these were set at 100 per cent intensity. Impressively, the model suffered minor cracks but remained standing.

"Millions of people live in inadequate and temporary houses and many thousands of people, sometimes tens of thousands, die in the collapse of buildings during devastating earthquakes," says Hickson. "These buildings are sometimes crudely built earth homes, but often are poorly constructed, using reinforced concrete, concrete hollow block or fired brick.

"Earth building material is abundant, widespread and freely available. Education, training or sharing knowledge is all that is required to make such homes safer if people are willing to adopt some simple changes to the way they build.

"Furthermore, by utilising local indigenous materials, vernacular styles and appropriate climate responsive designs, we will have also delivered the most sustainable solution for communities with limited resources."

More info: nancy.gewargis@uts.edu.au


Sensational Materials

The oldest lunar zircon

The Earth from moon, as recorded on the Apollo 17 mission (Photo NASA)

Four and a half billion years ago the Moon was covered in an ocean. But this wasn’t an ocean of water but of molten magma. Now scientists from the Curtin University of Technology have analysed a lunar sample brought back by the Apollo 17 mission in 1972 that formed from that magma ocean. They’ve found a zircon crystal in that sample and determined the age of that crystal. In so doing they’ve thrown new light on the Moon’s early history and of our own planet.

“The zircon we discovered would have formed as the Magma Ocean crystallised, and suggests that the Magma Ocean existed for the first 100 million years of the Moon’s history,” says Dr Alexander Nemchin, of Curtin’s Department of Applied Geology.

“The mineral zircon (ZrSiO4) is well-known for its stability and ability to precisely date geological processes in terrestrial rocks, but the discovery of zircon in the lunar samples we examined means that we can now determine the chronology of major events in the Moon’s evolution.”

The researchers determined that the zircon is 4.42 billion years old, and the finding was announced in January in the prestigious international scientific journal, Nature Geoscience.

The moon is generally believed to have formed from the debris of a collision between the Earth and a Mars-sized body more than 4.5 billion years ago. The heat generated by the coalescing of debris that formed the Moon led to the creation of a magma ocean about 500 to 800 kilometres thick.

The cooling, or crystallisation, of the lunar magma ocean resulted in the moon as we observe it today says Dr Nemchin, although there has been considerable debate over the precise timing of this crystallisation of the magma ocean.

"The timing of lunar magma ocean crystallisation remains loosely constrained to the first 250 million years of lunar history," he explains.

However, he says analysis of the zircon grains can give a precise timing to this process because zircon is formed during the very last stages of solidification of the magma ocean. Zircon is used to precisely date geological processes in rocks because it contains uranium which decays into lead at a known rate. Using a sensitive high-resolution ion microprobe the earth scientists measures the ratio of uranium atoms to its breakdown product (lead atoms) to derive an age for the crystal.

By analysing the ratio of lead and uranium isotopes in the lunar zircon, Dr Nemchin and his colleagues, dated the zircon grain as being 4.42 billion years old. This shows the Moon's crust was almost completely formed within about 100 million years.

And this discovered, using a rock picked up by an astronaut back in 1972 can tell us a lot about our own planet.

“Understanding the time constraints related to the lunar Magma Ocean can also provide important constraints on the development of the Earth-Moon system,” explains Dr Nemchin.

More info: a.nemchin@curtin.edu.au

Laser printers release dangerous particles

Professor Lidia Morawska

The identity and origin of tiny, potentially hazardous particles emitted from common laser printers have been revealed by a new study at Queensland University of Technology.

Professor Lidia Morawska from QUT's International Laboratory for Air Quality and Health led the study which aimed to answer questions raised by earlier findings that almost one third of popular laser printers emitted large numbers of ultrafine particles.

These tiny particles are potentially dangerous to human health because they can penetrate deep into the lungs.

Professor Morawska said the latest study found that the ultrafine particles formed from vapours which are produced when the printed image is fused to the paper.

"In the printing process, toner is melted and when it is hot, certain compounds evaporate and those vapours then nucleate or condense in the air, forming ultrafine particles," she explains. "The material is the result of the condensation of organic compounds which originate from both the paper and hot toner."

The study compared a high-emitting printer with a low-emitting printer and found that there were two ways in which printers contributed to the formation of these particles.

"The hotter the printer gets, the higher the likelihood of these particles forming, but the rate of change of the temperature also contributes," says Professor Morawska.

"The high emitting printer operated at a lower average temperature, but had rapid changes in temperature, which resulted in more condensable vapour being emitted from the printer.

"The printer with better temperature control emitted fewer particles."

Professor Morawska said this research provided information which would help consumers better understand the risks of laser printers and would help the printer industry to design low or no emission printers.

The paper is available at: http://pubs.acs.org/doi/abs/10.1021/es802193n.

Quokka comes alive

Australia has a new machine for probing the structure of materials at the nanoscale. It’s called the Quokka and it’s a state-of-the art small-angle neutron scattering instrument.

Quokka the machine (named after a small native marsupial) lives outside of Sydney at Lucas Heights and forms part of the Bragg Institute operated by the Australian Nuclear Science and Technology Organisation (ANSTO). The Bragg Institute leads Australia in the use of neutron scattering and X-ray techniques to solve research and industrial problems.

And now researchers at the Bragg Institute have celebrated a major milestone with Quokka by analysing the first data from their new instrument.

Quokka will be one of the best small-angle neutron scattering (SANS) instruments in the world. SANS is a highly versatile technique for investigating a wide range of materials including polymers, emulsions, colloids, superconductors, porous materials, geological samples, alloys, ceramics and biological molecules such as proteins and membranes.

SANS is a powerful technique for looking at structures on the nanoscale from 1 to several hundred nanometres. When a neutron beam impinges on a sample, some neutrons scatter along a path that differs from the transmitted beam by as little as several hundredths of a degree. This ‘small-angle’ scattering provides information about relatively large structural details on the nanoscale. SANS can provide particle sizes, shapes and distributions averaged over a complete macroscopic sample.

Quokka will have a wide variety of uses and will be soon be utilised within a collaborative Food Science project with CSIRO Food Futures Flagship and University of Queensland.

A trace of the first data produced by Quokka

The instrument will be used to understand key factors that control the formation of resistance starch which, when consumed, has been shown to reduce the development of colorectal cancer, says Quokka team leader, Dr Elliot Gilbert.

“We already have an excellent understanding of the process in vitro [procedures performed in a controlled environment outside a living organism], but will soon be extending those studies in vivo [inside a person]. Quokka will allow us to see how and when starch molecules break down in the process. The potential outcome will be to allow consumers to purchase 'resistant starch' in common food items such as bread,” says Gilbert.

The success of Quokka’s first data output represents the culmination of more than eight years work and proves the instrument is working as planned. Indeed, it is capable of producing high quality data at break neck speeds.

"We observed neutron scattering from the structure we were analysing in a matter of seconds, which was incredibly exciting," Gibert says.

The sample Quokka analysed was a polymer that he had been studying for more than 10 years. The next step is to invite users to come and test their own samples and shake down any potential problems. They will then fine tune and make improvements based on their suggestions, said Elliot.

Researchers from as far as Germany have already expressed interest. A formal call for proposals will be issued in March, with the first researchers expected in September.

More info: http://www.ansto.gov.au/research/bragg_institute.html