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Mon, 18 Sep 2017 9:50:38 EDT

A large international collaboration has used a specialised technique on the infrared microspectroscopy (IRM) beamline at the Australian Synchrotron to determine the structure of proteins in individual silk fibres that has potential use in the design of new biomaterials with desirable properties.

The technique, hyper-spectral infrared imaging, is a powerful analytical tool because it can establish the link between micro-/nano-structures and specific material properties of biomaterials. 

The orientation of the C = O, C-N, and N-H bonds in amide structure of the L-section of silk fiber confirmed in this study by the hyper-spectral imaging

The investigation included researchers from Swinburne University, Tokyo Institute of Technology, Deakin University, the Australian Nanofabrication Facility, The Centre for Physical Sciences and Technology in Lithuania, Dr Mark Tobin and Dr Pimm Vongsvivut from the Australian Synchrotron, in a study that was published in Scientific Reports

The extraordinary properties of silk are linked to the molecular orientation of polypeptides and its amorphous/crystalline composition in the protein structure. 

“The goal was to identify the orientation of proteins in different parts of the fibre and to look at how laser treatment can alter the protein structure in the silk fibre,” said Dr Mark Tobin, Principal Scientist ‒ IR beamline at the Australian Synchrotron. 

“You would need to know the effect of a laser on silk, for example, in order to 3D print the silk,” said Tobin.

Molecular orientation is responsible for the optical, mechanical and thermal properties of biomaterials. In this study, the researchers were interested in investigating the molecular orientation of specific protein bonds in the silk that play a critical role in its strength.

Infrared imaging at the Australian Synchrotron can access molecular orientation of the protein structure directly from a single silk fibre.

“You can obtain infrared absorption information that is selected based on the orientation of a particular chemical bond,” explained Tobin.

Hyper-spectral imaging

“Because the silk fibres are only 10 microns across and the synchrotron infrared beam is about half the size of that, we developed an optical device using a germanium crystal that allowed the beam to pass through the fibre’s cross section at four times higher resolution.”

This specific device, which was developed by Vongsvivut and Tobin at the Australian Synchrotron, was recently used successfully on carbon fibres and has shown to be efficiently suitable in a broad range of applications.

Silk is a semi-crystalline material that is birefringent, which means as well as absorbing polarised light in one way it actually rotates the polarisation.

The researchers used an infrared filter to progressively rotate the polarisation of the synchrotron beam and collected four infrared (chemical) images ‒ each one with the polarisation 45 degrees apart. This unique four polarisation method was developed by the collaborative researchers in Japan. Using a mathematical formula to transform the polarisation data, they were able to work out the molecular orientation of the protein structure in the silk fibres.

Infrared imaging

In an infrared image, the intensity of the colour indicates the strength of the absorbance. 

“In the infrared wavelengths, you see peaks in the spectra that tell you where the light is being strongly absorbed,“ said Tobin.

“A bond vibrates at a certain energy level at a natural frequency. If light comes in at the same frequency, it can absorb some of that infrared light and vibrate to a slightly higher level,” explained Tobin.

High resolution 1.9 μm ATR FT-IR maps at 1.9 μm resolution of the longitudinal (L) cross sections of silk presented in auto-scale for better viewing

The spectra generated in infrared images revealed that the primary vibration of the Amide II bond was all along the direction of the chain and the vibration of the Amide A bond was perpendicular to the fibre.

“With that information, our collaborators were able to work out that the protein molecules oriented in a particular way in the fibre.”

When a pulsed laser was used on one of the bonds, it disrupted the Amide A bond, changing the protein structure.  

“Although the bulk information of silk fibres has probably been known, it has not been possible to measure molecular orientation on single fibres before,” said Tobin.

doi:10.1038/s41598-017-07502-3 

 

 

 


Wed, 13 Sep 2017 13:52:14 EDT

Call for nominations

Continuing a tradition set up by the Australian Synchrotron Research Program (ASRP), ANSTO is seeking submissions for the ANSTO, Australian Synchrotron Thesis Medal, named in honour of Dr Stephen Wilkins.

This medal is awarded annually to the PhD student at an Australian or New Zealand University who is judged to have completed the most outstanding thesis of the past two years whose work was undertaken at and acknowledges the Australian Synchrotron, or the Australian National Beamline Facility (ANBF), or whose work acknowledges and was undertaken under the auspices of the International Synchrotron Access Program (ISAP) or the ASRP.

Nominations are invited for the 2017 ANSTO, Australian Synchrotron Stephen Wilkins Medal, which will be awarded to the candidate producing the most outstanding thesis and whose degree was awarded, but not necessarily conferred, in the period 1 July, 2015 – 30 June, 2017. The awardee will receive a monetary prize of $3,000 funded by a bequest from the Wilkins family and by ANSTO to support career development.

Conditions of the Award

·      Applicants are able to nominate themselves; however, a letter of support for their application is required from their PhD Supervisor(s).

·      To be eligible, applicants must have completed their PhD while enrolled at an Australian or New Zealand University and must have been awarded their PhD within 2 years prior to 30 June of the current year. Applicants may still apply if their PhD has been awarded but not conferred within this time period.

·      Nominations are assessed by a Medal Selection Committee appointed by the Director of the Australian Synchrotron, ANSTO.

·      The award is made to the PhD student at an Australian or New Zealand University who is judged to have completed the most outstanding thesis of the past two years whose work was undertaken at and acknowledges the Australian Synchrotron, or the ANBF, or whose work acknowledges and was undertaken under the auspices of the ISAP or the ASRP.

·      Synchrotron radiation techniques should have made a major contribution to the thesis.

·      If the Medal Selection Committee is unable to identify a thesis of sufficient quality amongst the applications submitted, an award will not be offered.

·      If the Medal Selection Committee identifies a number of high quality applications in addition to the Awardee, they may offer a “Highly Commended” certificate.

·      The Awardee must be available to attend the ANSTO User Meeting to receive their award and present their work in a plenary session.

·      ANSTO may publicise successful candidates.

Application Details

There is no application form.  Applications can be submitted by either printed or electronic versions, and must include the following:

·      Three copies of the thesis along with evidence of the thesis being passed.

·      A cover letter providing an overview of the research undertaken during the PhD candidature of the applicant, their academic achievements and future plans for their research career.

·      Letters of support from the candidate’s PhD supervisor and Head of Department or School describing the significance of the work and the contribution it has made to the relevant field.

·      Copies of the examiners’ reports.

·      A list of publications resulting from the thesis.

·      A copy of the applicant’s CV.

ANSTO will retain one copy of the successful thesis if submitted in hard copy.  All other copies will be returned to the applicants at the end of the selection process.

The Medal will be presented to the chosen candidate at the ANSTO User Meeting 22nd - 24th November 2017.  The winning candidate will be invited to attend the User meeting and present a talk on their research. 

Any queries should be emailed to tiffany.morris@synchrotron.org.au

Applications should be forwarded to:

Professor Andrew Peele

Director

Australian Synchrotron, ANSTO

800 Blackburn Road

Clayton, Victoria 3168

Application deadline – Close of Business Monday 16th October 2017 


Thu, 7 Sep 2017 9:48:34 EDT

A large collaboration led by researchers from the University of Wollongong has used the Australian Synchrotron to investigate a promising carbon coated cathode material for rechargeable sodium ion batteries that had a very long life.

The research demonstrated that  a new compound, an iron-based pyrophosphate-based sodium composite, could compete with other iron-based cathode materials for large scale applications, such as wind and solar storage, because  its charge retention capacity was close to 90 per cent after 1100 cycles at 5 C.

 

Low energy density, sluggish sodium kinetics and poor cycling stability have been the main barriers to the widespread use of sodium ion batteries as less costly alternative to lithium batteries.

The synchrotron was used to investigate the electrochemical mechanism at work in a new cathode material, Na3.32Fe 2.34 (P2O7) as reported in Advanced Materials.

The multiple anions of the new compounds give them high structural and thermal stability with only small volume changes in the unit cell.

Qinfen Gu, a senior scientist on the powder diffraction beamline, said it was possible to charge and discharge the battery in real time while sending X-rays through the nanoparticles, which revealed what was happening at a structural level in the cathode material during cycling.


The diffraction data indicated a single phase transition during charge and discharge, which helped explain its superior electrical performance.

A reversible electrochemical reaction, suggested by continuous lattice breathing, also took place in the material.

“The movement of the sodium ions can cause the cathode to expand or contract, which can degrade the material and interfere with the movement of electrons,” said Gu.

In this case the researchers noted that only a small change in lattice parameters and unit cell offered strong support for the stability of the structure during cycling.

The application of a carbon coating on the cathode material improved its thermal and structural stability, enhanced its electrical conductivity and contributed to a high rate capacity. 

The investigators also attributed superior electrochemical performance to a dramatic increase in the transfer rate of electrons across different layers of the material and an acceleration of the transfer of sodium ions by the uniform amorphous carbon layer.

Experiments confirmed that without the carbon coating, the material degrades very quickly and after 500 cycles, charge retention capacity drops.

“The electrolyte attacks the cathode material and the carbon coating slows this down,” explained Gu.

The material would be low cost because it is primarily composed of ample elements, sodium and iron, and offers improved safety.

 Other collaborating institutions included the University of South China, the University of Queensland and Sichuan University (China). 

http://dx.doi.org/10.1002/adma.201605535


Wed, 30 Aug 2017 14:12:13 EDT

ANSTO has secured $80.2 million in new funding to expand the research capabilities of the Australian Synchrotron. 

The funding boost was made by the New Zealand Synchrotron Group Limited (representing funding from the New Zealand Government and 10 New Zealand universities and research institutions), the Defence Science and Technology Group and 19 universities and medical research institutes across Australia. 

The new funding will expand the number of beamlines at the Synchrotron from 10 to as many as 18, increasing research output at the facility and helping keep up with significant researcher demand for the state-of-the-art facility.

The first stage of the expansion will see the construction of the Micro-computed Tomography (MCT) beamline and the Medium Energy XAS (MEX) beamline: 

•        The MCT beamline will complement the Imaging and Medical Beamline (IMBL), by allowing 3D structures to be studied in close detail, which will enable advanced research in the fields of biological and health sciences.

•        The MEX beamline will enable mapping of lighter elements such as sulphur, phosphorous, chlorine, calcium and potassium, with applications across sectors including aiding in the development of cancer treatment.

These beamlines will be closely followed by a Small Angle X-ray Scattering (BioSAXS) beamline. Supported by the New Zealand Synchrotron Group’s significant $25 million investment, the beamline will allow for detailed protein studies focussed on improving drug design and validation processes. 

Minister for Industry, Innovation and Science, Senator the Hon Arthur Sinodinos, welcomed the funding for the beamline expansion, which will be supported by the Australian Government’s significant operational investment made via the National Innovation and Science Agenda (NISA).

The NISA provides $520 million in operational funding to the Australian Synchrotron, which includes operational funding for the new beamlines.

Minister Sinodinos said the scale of the contributions highlighted the extremely significant role the Synchrotron plays in Australia’s science and innovation ecosystem. 

“The Australian Synchrotron is one of our most important pieces of landmark research infrastructure, which on a daily basis delivers practical benefits across a variety of vital areas,” Minister Sinodinos said.

“This is applied science at its best, with applications for medical researchers, the environment and industry.

“The Australian Government welcomes this new investment to expand capacity at the Synchrotron, which will be supported by our significant operational investment made via the National Innovation and Science Agenda (NISA).”

ANSTO CEO, Dr Adi Paterson, said this was the latest ANSTO collaboration that provides new opportunities for industry and researchers. 

“ANSTO has been working to secure more than $100 million in capital funding to ensure the facility remains world-class and continues to meet the needs of researchers and industry,” Dr Paterson said. 

“This is a great first step, and we look forward to continuing to work with industry and government to support the vitally important work of our scientists and researchers.” 

Australian Synchrotron Director, Professor Andrew Peele said the expansion will alleviate demand issues and enable new research opportunities. 

“This expansion will give Australian and New Zealand industry and our best and brightest scientific minds access to even more specialised tools and techniques needed for important research,” said Professor Peele.

“This will enable them to continue to compete on the world-stage and deliver real-life benefits to the community.” 

ANSTO will continue to work with universities and other stakeholders to secure the remainder of the required funding. 

Contributors to the project include:

Australian National University - Charles Sturt University - Curtin University – Deakin University - Macquarie University – Monash University - Queensland University of Technology - RMIT University - Swinburne University - University of Canberra - University of Melbourne - University of New South Wales - University of Queensland - University of the Sunshine Coast - University of Sydney - University of Tasmania - University of Western Australia - University of Wollongong – Walter and Eliza Hall Institute of Medical Research – ANSTO - Defence Science and Technology Group - New Zealand Synchrotron Group (including contributions from the New Zealand government and 10 universities and research institutions) 

Media enquiries: 

Minister Sinodinos: Nat Openshaw 0409 049 128

ANSTO / Australian Synchrotron: Phil McCall 0438 619 987

 


Mon, 28 Aug 2017 9:39:18 EDT

Queensland researchers have shown that single crystals, typically thought of as brittle and inelastic, are flexible enough to be bent repeatedly and even tied in a knot.

Researchers from Queensland University of Technology and The University of Queensland (UQ) determined and measured the structural mechanism behind the elasticity of the crystals down to the atomic level using the Australian Synchrotron.

Video: Copyright QUT

Their work, published in Nature Chemistry, opens the door for the use of flexible crystals in applications in industry and technology. 

The research was led by ARC Future Fellows Associate Professor Jack Clegg in UQ’s School of Chemistry and Molecular Biosciences and Associate Professor John McMurtrie in QUT’s Science and Engineering Faculty. 

Associate Professor McMurtrie said the results challenged conventional thinking about crystalline structures.

“Crystals are something we work with a lot – they’re typically grown in small blocks, are hard and brittle, and when struck or bent they crack or shatter,” he said.

“While it has previously been observed that some crystals could bend, this is the first study to examine the process in detail.

“We found that the crystals exhibit traditional characteristics of not only hard matter, but soft matter like nylon.”

The researchers grew bendable crystals about the width of a fishing line and up to five centimetres long from a common metal compound – copper (II) acetylacetonate.

They mapped changes in the atomic scale structure when the crystals were bent using X-ray measurements performed at the Australian Synchrotron.

A view of the structural deformation on the elongated (left) and compressed (right) areas of the crystal.

Dr Jason Price, a beamline scientist at the Australian Synchrotron, who helped design the experiments, explained that preliminary studies were undertaken on the MX1 beamline and followed by extensive measurements on the MX2 beamline.

“This experiment really shows the opportunity to look at variation within a single crystal. The microfocus capacity of the beam at MX2 is such that it can gather data from different parts of the crystal, so, when it is under strain from expansion or compression.”

 Crystals from six other structurally related compounds, some containing copper and some other metals, were also tested and found to be flexible.  

Associate Professor Clegg said the experiments showed that the crystals can be repeatedly bent and return quickly to their original shape with no signs of breaking or cracking when the force bending them is removed.

“Under strain the crystal molecules reversibly rotate and reorganise to allow the compression and expansion required for elasticity and still maintain the integrity of the crystal structure,” he said.

“The ability of crystals to bend flexibly had wide-ranging implications in industry and technology.

“Crystallinity is a property that underpins a variety of existing technologies, including semi-conductors and lasers which are used in almost every electronic device from DVD players to mobile phones and computers.

“But the hardness that makes them suitable for high-strength industrial components limits their use in other technologies. Flexible crystals like these could lead to new hybrid materials for numerous applications from components of planes and spacecraft to parts of motion or pressure sensors and electronic devices.”

Associate Professor McMurtrie said the method the researchers have developed to measure the changes during bending could also be used to explore flexibility in any other crystals.

“This is an exciting prospect given that there are millions of different types of crystals already known and many more yet to be discovered,” he said.

“Bending the crystal changes its optical and magnetic properties, and our next step is to explore these optical and magnetic responses with a view to identifying applications in new technologies.”

The research was funded by an ARC Discovery Grant and supported by the Australian Synchrotron. Research collaborators and co-authors of the study are: Anna Worthy, Professor Chen Yan, and Yanan Xu (QUT) and Dr Arnaud Grosjean, Dr Michael Pfrunder and Dr Grant Edwards (UQ).

http://dx.doi.org/10.1038/nchem.2848  

For interview:

QUT Associate Professor John McMurtrie, j.mcmurtrie@qut.edu.au   07 3138 1220

UQ Associate Professor Jack Clegg, j.clegg@uq.edu.au  0408 642082


Thu, 13 Jul 2017 11:43:18 EDT

International researchers led by Assoc Prof Chris McNeill’s group at Monash University have used an X-ray scattering at the Australian Synchrotron to understand how microstructure contributes to the performance of an organic solar cell made with a semiconducting polymer and fullerene thin film.

The investigators evaluated the performance, microstructure and photophysics of dual stack bulk heterojunction (BH) solar cells made with a low bandgap polymer and fullerene thin film in a study published in Advanced Energy Materials.

The research relied on a range of techniques including X-ray scattering, photoluminescence spectroscopy, ultrafast transient absorption spectroscopy and transient photovoltage measurements, to gain a better understanding of how the choice of fullerene acceptor influences microstructure,  photophysics and contribute to device performance.

A bulk heterojunction device is fabricated by coating a blend of two organic semiconductors between two electrodes. Thin films, which are usually less than 100 nanometres thick, offer production advantages for solar cells.

The close blending of materials is required for high performance because photo-generated excitons travel less than 10 nanometres before recombining, with photocurrent generation proceeding through via the dissociation of excitons a material interfaces. Efficient devices therefore require the blend to be optimally structured on the nanoscale.

2-dimensional X-ray scattering patterns of (a) PC61BM, (b) PC71BM and (c) ICBA. (d) line profiles integrated from 2D scattering patterns and (d) fitted parameters.

 

Advanced characterisation techniques are used to understand how microstructure, or morphology, contributes to power conversion efficiency.

Fullerenes act as electron acceptors in a device. Three novel compounds, PC71BM, PC61BM and ICBA were blended with a low band gap polymer, PBDTTT-EFT for the study.

The highest efficiency (9.4%) was found in the blend using the acceptor PC71BM, which also had the highest visible light absorption.

Prof Chris McNeill and collaborators used Synchrotron-based grazing incidence wide angle X-ray scattering (GIWAXS) to determine the molecular orientation of the polymer with respect to the substrate in the bulk of the thin film.  

The GIWAXS measurements provided information about the orientation of polymer crystallites in the bulk, with these crystallites needing to be properly aligned in order for charges to travel through the material more easily.

Resonant soft X-ray scattering was also carried out by co-author Dr Lars Thomsen at the Advanced Light Source at Lawrence Berkley National Laboratory in the US to clarify the structure and purity of domains.

Thomsen, a member the soft x-ray spectroscopy beamline team at the Synchrotron, has undertaken previous collaborations with the McNeill Group on organic electronics.

R-SoXS indicated that one of the blends, PBDTTT-EFT:PC71BM exhibited the largest domain size and highest domain purity, which was thought to facilitate charge separation and transport.

The scattering profiles also provided an indication of the roughness of the interfaces between the domains in the three compounds.

The R-SoXS and other methods suggested that the lower power conversion efficiency of the ICBA compound might be explained by rougher domain interfaces, lower crystallinity and smaller domain size.

Contributors include Dr Wenchao Huang and colleagues at Monash University, Dr Eliot Gann (now at Brookhaven National Lab), researchers from the University of California Los Angeles, the Indian Institute of Technology Bombay and Victoria University of Wellington.


Wed, 5 Jul 2017 11:55:16 EDT

A Monash-led group of geoscientists used the macromolecular crystallography beamline (MX2) Australian Synchrotron to help them determine the atomic structure of a new mineral discovered in a volcanic area of Far Eastern Russia. 

The research, which was published in American Mineralogist by Prof Joel Brugger of Monash and collaborators from Australia and Russia may provide insight into the processes responsible for the geochemical evolution of Earth. 

The authors reported that an analysis of Nataliyamalikite was challenging because of the small size of single crystals, composite nature of larger aggregates and the extreme light sensitivity of the mineral and the surrounding sulfur matrix. 

Nataliyamalikite grains could not be isolated using optical microscopy. 

X-ray powder diffraction measurements on microcrystals of Nataliyamalikite at 100 K indicated that  the structure was orthorhombic. 

The mineral which has only two atoms, thallium and iodide, in the asymmetrical unit cell, is considered to be a distorted version of rock salt.

The beam diameter was reduced to 7.5 nanometres by a collimator at the Australian Synchrotron MX2 micro-focus beamline to match the crystal size of the micro-aggregates of Nataliyamalikite, which were extracted from the amorphous sulfur matrix by focused ion beam scanning electron microscopy.

MX2 beamline scientist Dr Jason Price assisted in processing the beamline data, which was compared with a synthetic equivalent. 

Electron backscatter diffraction at Monash and in Russia confirmed an orthorhombic crystal lattice of the mineral at ambient conditions. 

The thallium-rich Nataliyamalikite forms in high temperature fumaroles, (thermal openings in areas surrounding a volcano) as a component of arsenic and sulfur-rich coating on lava and scoria around the vents.

In the paper, the authors also provided a description of the process that give rise to concentrations of thallium, leading to the formation of Nataliyamalikite.

Read more on the Monash website. 

 


Thu, 15 Jun 2017 11:41:00 EDT

More than 40 science and engineering graduate students, postdoctoral fellows and early career researchers from across the Asia-Oceania region attended the first Asia Oceania Forum (AOF) Synchrotron Radiation School in early June hosted by the ANSTO at the Australian Synchrotron and supported by the Australian Institute of Nuclear Science and Engineering (AINSE). 

The participants, who are interested in pursuing a career in synchrotron radiation-related fields, had the opportunity to attend a range of lectures and take part in practical sessions on six of the ten beamlines at the Australia Synchrotron.

Those who attended the week-long school came from China, Thailand, Japan, Korea, Taiwan, India, Singapore, New Zealand and within Australia to learn more about the theory and applications of synchrotron radiation for a wide range of science and technology research.

“We were greatly pleased by the level of interest in synchrotron technologies, which are proving to be invaluable across a range of applications and delighted to share Australian and international expertise with the group,” said Prof Richard Garrett, Senior Advisor, Strategic Projects, ANSTO, who was Co-Chair of the school with Dr Mike James, Head of Science at the Australian Synchrotron.

Guest lecturers travelled to Australia from South Korea and the US.

In addition to a general introduction to synchrotron radiation, light source, beamlines, and detectors, the curriculum included sessions on the techniques used on the Australian Synchrotron beamlines, such as medical imaging, powder X-ray diffraction, and micro fluorescence.

At the conclusion of the lectures and practical sessions, participants gave presentations based on their beamline investigations. 

“Actual hands on experience with the beamlines is invaluable for planning research projects and understanding the tremendous analytical capabilities of the instruments,” said Dr James.

The Asia Oceania Forum for Synchrotron Radiation Research (AOFSRR) is an association of the eight synchrotron operating and user nations in the Asian region: China, Thailand, Japan, Korea, Taiwan, India, Singapore and Australia,. Its mission is to strengthen regional cooperation in, and to promote the advancement of, synchrotron radiation research. Three additional countries are associate members: New Zealand, Malaysia and Vietnam.

ANSTO has had a close association with the AOFSRR since its inception in 2006, when it operated the Australian Synchrotron Research Program which joined the Forum as a foundation member representing Australia. Since 2012 ANSTO has served as financial manager of the AOFSRR, to facilitate the payment of membership fees by the eight full member nations.

The main activities of the AOFSRR are to organise an annual workshop and an annual synchrotron school. The Japanese SPring8 facility hosted the school, then known as the Cheiron School, from 2007 until 2015. This has now been replaced by the AOF Synchrotron School which will rotate among the 8 member countries. The next school will be held in South Korea, followed by Thailand.


Wed, 24 May 2017 16:24:46 EDT

Advanced imaging reveals unusual, unseen patterns in seabird feathers

The identification of essential chemical elements in the feathers of long-distance migratory seabirds using advanced X-ray imaging techniques promises new insights into the underlying physiological processes behind feather growth.

In research published in Nature Scientific Reports, a team of investigators led by ANSTO biologist Nicholas Howell and Prof Richard Banati provided evidence of previously unseen spatial patterns in the distribution of metals that do not appear to be linked to physical characteristics in the feathers.

Because the patterns are not linked to pigmentation, thickness or other structural characteristics in the feathers, the authors suggest another unidentified mechanism may be at work.

“Our collaboration has produced some remarkable depictions of the feathers that let us see into complex and pattern-forming, biochemical processes in cells,” said Prof Banati.

High resolution images collected using the X-ray fluorescence microprobe and Maia spectroscopic detector at the Australian Synchrotron, revealed independent distribution of zinc, calcium, bromine, copper and iron.

In this investigation, the technique was applied to the whole feather, and required no subsampling or extraction procedures  in order to accurately identify elements.

 “Using this powerful instrument and Maia detector, David Paterson and Daryl Howard were able to scan samples that were several centimetres in length at micron resolution,” said Howell.

X-ray fluorescence microscopy allows you to view hard biological structures in their natural state. The detector system speeds up the scanning of the sample in real time and delivers data at unprecedented resolution.

The images, which have previously unachieved sensitivity and resolution, provide a distribution map of a range of chemical elements in the feather.

Understanding the development of bird feathers is important for understanding the evolution of birds, formation of organs, tissue regeneration and the health status of individual animals.

The findings also have significant potential application more broadly in developmental biology.

“The same basic biochemical mechanisms that allow feathers to develop in birds are at work in other animals and humans, “said Howell.

For example, the identification of a distinct, repetitious pattern in the concentration of zinc in all samples was of particular interest.

Zinc is an essential element in birds for growth, the formation of enzymes, the development of the skeleton and a range of physiological functions.

These zinc bands resembled but were not related to distinct growth bands.

The exact mechanism that leads to the regular deposits of zinc is unknown but the scientists  noticed that the number of zinc bands appears to be the same as the number of days the feather grows, e.g. the duration of the moulting period.

“We do not have entirely accurate data on the rate of feather growth in a migratory seabird, which needs to be observed under conditions of the animal’s natural life-cycle,” said Howell.

“Nonetheless, such highly regular, biological patterns hold important information , because similar to tree rings , they are a natural time stamp that records events during the growth of these patterns.” said Howell.

Therefore, the patterns in the feathers may be useful in assessing the bird’s health and nutritional status retrospectively, in the way that tree rings indicate  past environmental events, such as droughts and floods.

The feathers came from three species of migratory shearwaters, birds that are known to travel over 60,000 kilometres per year on their migration to breeding areas.

Mr Howell said none of the work would have been possible without the painstaking field work in remote locations.

Single breast and wing feathers from the fleshfooted, streaked and short-tailed shearwater were collected on Lord Howe Island, several Japanese islands and Bundeena Beach (NSW) under the direction of co-author Dr Jennifer Lavers of the Institute of Marine and Antarctic Studies at the University of Tasmania.

 “It is very difficult to image and measure metals in biological samples, but it is something we can do with a variety of techniques at ANSTO using X-rays, neutrons and isotopes,” said Howell.

Last year, a similar approach was used to detect and measure strontium in the vertebrae of sharks.

The study revealed that the strontium correlated with the age of the individual and allowed age to be determined without reference to growth bands.

 


Tue, 4 Apr 2017 11:23:59 EDT

Infrared (IR) imaging technology at the Australian Synchrotron, developed specifically for carbon fibre analysis, has contributed to a better understanding of chemical changes that affect structure in the production of high-performance carbon fibres using a precursor material.

A research collaboration led by Carbon Nexus, a global carbon fibre research facility at Deakin UniversitySwinburne University of Technology and members of the Infrared Microspectroscopy team at the Australian Synchrotron, has just published a paper in the Journal of Materials Chemistry A, that identified and helped to explain important structural changes that occur during the production of carbon fibres.

The research was undertaken to elucidate the exact chemical transformation occurring during the heat treatment of polyacrylonitrile (PAN), which produced structural changes.

Left to right: Nishar Hameed, Maxime Maghe and Srinivas Nunna on the Australian Synchrotron Infrared Spectroscopy beamline.

The majority of commercial carbon fibres are manufactured from PAN but there has been an imperfection that occurred during production that affected its material properties. 

Because the conversion of PAN to carbon fibre did not occur evenly across the fibre, it resulted in a skin-core structure. 

Manufacturers want to prevent the formation of the skin-core structure in order to enhance the strength of the fibres.

The research lead by Dr Nishar Hameed provides the first quantitative definition on the chemical structure development along the radial direction of PAN fibres using high-resolution IR imaging. 

“Although it has been more than half a century that carbon fibres were first developed, the exact chemical transformations and the actual structure development during heat treatment is still unknown”. 

“The most significant scientific outcome of this study is that the critical chemical reactions for structure development were found to be occurring at a faster rate in the core of the fibre during heating, thus disrupting the more than 50-year-old belief that this reaction occurs at the periphery of the fibre due to direct heat.”

A multitude of experimental techniques including IR spectroscopy confirmed that structural differences evolved along the radial direction of the fibres, which produced the imperfection.

The difference between skin and core in stabilised fibres evolved from differences in the cross linking mechanism of molecular chains from the skin to the core. 

The information could potentially help manufacturers improve the production process and lead to better fibres.

“Using a technique called Attenuated Total Reflection (ATR) to focus the synchrotron beam, the IR beamline allowed the research team to acquire images across individual fibres, to see where carbon-carbon triple bonds in the PAN were being converted to double bonds,” said Dr Mark Tobin, Principal Scientist, IR, at the Australian Synchrotron, who is a co-author with Dr Pimm Vongsvivut and Dr Keith Bambery.

“Previous IR studies have been conducted on fibre bundles and powdered fibres, while we were able to analyse the cross section of single filaments.” 

To acquire detailed images of the fibres, which are only 12 microns across, the IR team modified the beamline for the experiment using a highly polished germanium crystal to focus the IR beam onto the fibres.

Lead author Srinivas Nunna received a post graduate research award from the Australian Institute of Nuclear Science and Engineering (AINSE) to support the study. 


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