At first, he said, most users were condensed-matter physicists. Then, protein crystallographers took an interest as they realized how valuable synchrotron X-rays were for solving protein structures — provided they had big enough samples to put in the beam, that is.
P rotein crystallography and a few other uses in the life sciences led to an upsurge in biological scientists at light sources. A few years ago, however, solving protein structures began to be taken over by cryogenic electron microscopy cryo-EM , which uses standalone instruments that do the job better than synchrotrons.
D ong and I then stopped at the X-ray fluorescence station, where a poster showed pictures of three different kinds of plants studied at the station. A rice plant was also depicted on the poster. The researchers had used the BSRF to find ways to reduce the toxicity of the mercury in rice, in particular exploring the use of selenium.
At this station they are locating exactly where the mercury and selenium combine. But the work of pharmaceutical firms at the facility revealed certain differences between Western and Chinese light sources. I n the West, firms such as Novartis, Merck and Pfizer are big, powerful and rich enough to develop a drug from beginning to end. This makes it harder to work together. F or Dong, synchrotrons appear to be approaching a limit on possible brightness imposed by the optics — limits on the size of the beam spot and focusing.
Dong also mentioned new ideas for the facilities, such as an energy recovery linac proposed by researchers at Cornell University. Hopefully, such innovations will secure a strong future for synchrotron sources in the decades ahead. Close search menu Submit search Type to search. Topics Astronomy and space Atomic and molecular Biophysics and bioengineering Condensed matter Culture, history and society Environment and energy Instrumentation and measurement Materials Mathematics and computation Medical physics Optics and photonics Particle and nuclear Quantum.
But the basis of its magnetism is poorly understood, which hampers efforts to design even better spintronic materials. That level of detail could only have been uncovered in a synchrotron experiment, Moewes points out. The team explores the charge-transfer interplay that occurs at interfaces between metal surfaces and organic molecules. In some of these systems, for example in optoelectronic devices, the molecules absorb light and transfer electrons through neighboring molecules to a metal electrode.
In other systems, the molecules modify electric current for select applications. When they compared the mixed-molecule film to those with just a single component, the group found that the PTCDA-silver bond elongated, suggesting it became weaker, and the CuPc-silver bond contracted, suggesting it became stronger.
But analysis of the orbital energies showed the opposite was true: The bonds that elongated had become stronger, and those that shrunk became weaker. Using a standing-wave X-ray technique and quantum calculations, the researchers determined that the bond length adjustments brought PTCDA and CuPc to nearly equal heights above the surface.
That change caused CuPc to become a better electron donor and PTCDA a better acceptor, which improved charge transfer through the system—a key feature required of molecular electronic devices Nat. High temperatures, high pressures, and other harsh working conditions eventually cause these catalysts to fail, which causes downtime and raises costs.
Synchrotron methods are providing researchers with clues about catalyst failure mechanisms and strategies for avoiding them. In one such study, a team led by Bert M. Weckhuysen of Utrecht University used an X-ray nanotomography method to examine a series of fresh and used fluid catalytic cracking catalysts.
Oil refiners use such catalysts to produce gasoline and other products from crude oil. The catalysts typically consist of two active components held together by a binder: a zeolite with roughly 1-nm-wide pores and a clay with larger pores. Weckhuysen suggests that catalyst lifetimes might be extended by coating the catalysts with a clog-resistant macroporous layer.
To sort out the details of the pore-clogging process, the Utrecht team again turned to a synchrotron method. This time they generated visual evidence for two types of clogging mechanisms. In one, iron originates from porphyrin-like crude oil molecules, and in the other, iron comes from refinery equipment. Researchers previously had proposed separate mechanisms, but the team provided the first direct visual evidence for both ACS Catal.
Synchrotron-based X-ray diffraction has also helped with the design of catalysts that scrub nitrogen oxides NO x from gas streams, including those emitted by vehicles and power plants. Researchers from Fudan University developed a nanomaterial in which NO x -stripping catalyst particles made of vanadium oxide sit on top of hollow tungsten oxide rods.
The team designed the rods to trap catalyst-poisoning alkali metals and thereby protect the catalyst. X-ray analysis of used catalyst particles showed that, indeed, the alkali atoms were trapped inside the rods. Most people are completely dependent on batteries to power their many gadgets and devices.
Synchrotron users such as John S. Working with other Argonne scientists, Okasinski used hard X-ray methods in a series of studies on lithium-air batteries. Li-air batteries could potentially provide much more energy per weight than lithium-ion batteries used in many current electronics.
But Li-air batteries tend to fail quickly. The studies turned up multiple findings. First, trace amounts of water in the electrolyte solution, likely from electrolyte decomposition, triggered unwanted reactions.
For example, the reactions caused the lithium anode to continuously decompose and form lithium hydroxide. The team also found that the lithium hydroxide layer was riddled with microscopic channels that enabled the battery to continue running—albeit weakly—until all of the lithium was consumed. Overall, the findings suggest that a decomposition-resistant electrolyte would mitigate some of the problems and improve battery performance. In November , Eliezer Rabinovici sat in a large Bedouin tent on the southeast coast of the Sinai Peninsula contemplating the chances for scientific cooperation between Israeli and Arab scientists.
In , the first experiments were carried out using synchrotron light siphoned off from a particle collider at Cornell in the USA. Over the years, the number of experiments using synchrotron light increased, but the scientists still had to use the light that was a by-product of particle collider machines; there was no dedicated synchrotron light source.
This changed in , when the UK built the world's first synchrotron dedicated to producing synchrotron light for experiments at Daresbury in Cheshire. Now there are around 40 large synchrotron light sources around the world. These scientific facilities produce bright light that supports a huge range of experiments with applications in engineering, health and medicine, cultural heritage, environmental science and many more.
The generation of a synchrotron is related to the technology it uses to produce synchrotron light. Synchrotrons were originally developed as "atom-smashers", used by particle physicists to study the basic constituents of matter.
The synchrotron light produced by these machines was considered a nuisance. First generation synchrotrons were built primarily for high-energy particle physics, with synchrotron light experiments performed parasitically. Second generation synchrotrons were solely dedicated to the production of synchrotron light, and used bending magnets to generate synchrotron light; the UK built the first of these at Daresbury in Third generation synchrotrons are different, because they use special arrays of magnets called insertion devices, which cause the electrons to wiggle, creating even more intense and tuneable beams of light.
This capability holds the key to answering some of the fundamental questions about the world around us, such as: what is our planet made from? What are the processes that sustain life? How can we conquer viruses? These questions can only be answered at the molecular level, and this is where lightsources come in. Find out more Visit lightsources. This dedicated website is the result of collaboration between communicators from light source facilities around the world, and is a regularly updated global resource providing information and updates about light sources, and opportunities for international collaboration.
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