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Artificial photosynthesis gets big boost from new catalyst
A new catalyst created by University of Toronto engineering researchers brings them one step closer to artificial photosynthesis — a system that, just like plants, would use renewable energy to convert carbon dioxide (CO2) into stored chemical energy. By both capturing carbon emissions and storing energy from solar or wind power, the invention provides a one-two punch in the fight against climate change.
“Carbon capture and renewable energy are two promising technologies, but there are problems,” says Phil De Luna (Department of Materials Science and Engineering PhD candidate), one of the lead authors of a paper published today in Nature Chemistry. “Carbon capture technology is expensive, and solar and wind power are intermittent. You can use batteries to store energy, but a battery isn’t going to power an airplane across the Atlantic or heat a home all winter: for that you need fuels.”
>Read more on the Canadian Light Source website
Ubiquitous formation of type-I and type-II bulk Dirac cones
… and topological surface states from a single orbital manifold in transition-metal dichalcogenides
Transition-metal dichalcogenides (TMDs) are renowned for their rich and varied properties. They range from metals and superconductorsto strongly spin-orbit-coupled semiconductors and charge-density-wave systems with their single-layer variants one of the most prominent current examples of two-dimensional materials beyond graphene.Their varied ground states largely depend on the transition metal d-electron-derived electronic states, on which the vast majority of attention has been concentrated to date.
>Read more on the Elettra website.
Image: Chalcogen-derived topological ladder in PdTe2.(a) Orbitally-resolved bulk electronic structure of PdTe2, indicating dominantly chalcogen-derived orbital character for the states in the vicinity of the Fermi level. (b) The measured out-of-plane dispersion together with the calculated band structure. Measured (c) and calculated (d) in-plane dispersion. (e,f) Spin-resolved energy distribution curves along the lines shown in (c).
Detecting microcracks in bone
Synchrotron scans suggest osteoporosis drugs may weaken bone
Osteoporosis, a disease that causes bones to become fragile, affects around 200 million people across the world and contributes to 8.9 million fractures every year. The bisphosphonate (BP) family of drugs is widely used in the treatment for osteoporosis. BP prevents the loss of bone by slowing down the natural renewal process that breaks down old bone. Although BP has been shown to reduce the number of fractures due to osteoporosis, there is increasing evidence that the drug’s long-term effects may not be entirely positive.
The issue lies in microcracks, thinner than a human hair, which occur in bone as a natural result of wear and tear. In healthy bone, these cracks are naturally repaired. In patients treated with BP, microcracks can accumulate and affect the strength of the bone.
Microcracks are too small to be seen with laboratory imaging techniques, but recent experiments show – for the first time in human bone – that they can be measured with synchrotron light, via a technique called micro-CT.
>Read more on the Diamond Light Source website
Quantum spectroscopy, for the measurements of dynamical current current thermalization
Nearly all spectroscopic measurements deals with the measurements of the average properties of the material. As an example, the reflectivity of a material is simply defined by the ratio between the number of photons which are reflected by the sample divided by the number of those arriving on it. The interest in measuring mostly average properties is the main drive of the standard scientific practice of repeating the measurements a lot of times so that the error made in one single measurements is averaged out by the repetition of the measurements. In this context the noise which determines fluctuation of the repeated measurements have always been considered as an impediment to a good quality measurements which needs to be mitigated by careful experimentalists.
The approach of repeated measurements is employed conspicuously in pump-probe experiments which are the prime way to study condensed matter out of its equilibrium state. In standards optical pump-probe experiments, ultrashort pulses are always used in pairs. The pump triggers the dynamical response and the probe is used to detect changes in the optical properties of the sample.
Read more on the Elettra website.
Image: Schematic view of the pump-probe set-up used for the experiments. The intensity of every single probe pulse was separately acquired with low-electronic-noise detectors for every pump-probe delay.
PSI spin-off GratXray wins Swiss Technology Award 2017
The young company GratXray is developing a new method for early diagnosis of breast cancer.
he Swiss Technology Award is considered Switzerland’s most significant technology prize and annually honours the best technological developments and innovations with high market potential in each of three categories: Inventors, Start-ups, and Innovation Leaders. Swiss companies as well as projects that were developed in Switzerland are eligible to compete. The spin-off GratXray received the prize in the Inventors category, in which young Swiss start-ups as well as innnovative business ideas with high market potential can qualify. In a multi-step application procedure, GratXray won out over its competitors.
Image: The Swiss Technology Award in the Inventors category goes to the PSI spin-off GratXray. Accepting the prize, from left to right: Marco Stampanoni, Zhentian Wang, Martin Stauber (CEO of GratXray), and Giorgio Travaglini (head of Technology Transfer at PSI). (Photo: Paul Scherrer Institute)
ForMAX – wood research for a better future
MAX IV Laboratory has received 100 million SEK from Knut and Alice Wallenberg Foundation for the investment in a new beamline, ForMAX, designed to serve both academia and industry. The new beamline is tailor-made for solving research questions related to materials from wood and will be a part of the transition to a bioeconomy. ForMAX is part of Treesearch, a national research platform for research and competence building in the field of new materials and specialty chemicals from forest raw materials.
How ‘super-microscopes’ are changing the face of European science
Today, 13th of November, in Brussels 16 organisations representing 19 light sources facilities across Europe have gathered to launch the LEAPS initiative and signed an agreement to strengthen their collaboration, in the presence of Robert-Jan Smits, Director General for Research and Innovation (RTD) at the European Commission, and Giorgio Rossi, Chair of the European Strategy Forum on Research Infrastructures (ESFRI).
LEAPS, the League of European Accelerator-based Photon Sources, aims to offer a step change in European cooperation, through a common vision of enabling scientific excellence solving global challenges, and boosting European competitiveness and integration. This will be achieved through a common sustainable strategy developed in coordination with all stakeholders, including national policy makers, user communities and the European Commission.
>Read more on the Diamond Light Source website
Inauguration of a Cryo-electron microscope platform at the ESRF
A TITAN KRIOS cryo-electron microscope has been inaugurated at the ESRF, the European Synchrotron, in Grenoble, France. The inauguration took place in the presence of Ada Yonath, chemistry Nobel Prize laureate in 2009, Francesco Sette, Director General of the ESRF and all the partners that jointly run the facility with the ESRF: the European Molecular Biology Laboratory (EMBL), the Institut de Biologie Structurale (IBS) and the Institut Laue-Langevin (ILL). This cryo-electron microscope will provide Europe with a new, innovative and complementary facility for structural biology, serving a vibrant scientific community and addressing new biology and health challenges.
Image: The team of the CRYO-EM. Credits: Stef Candé.
Ancient Egyptian papyrus’ ink reveals its origin
Ink in ancient manuscripts can shed lighton how life was in those times. Scientists from the University of Copenhagen (Denmark), the Autonomous University of Mexico and the ESRF have discovered copper in Egyptian papyri, ranging from the 1st century BC to the 3rd century AD, indicating that the ink originated from the soot in glass and metallurgy workshops and mines.
Image: A papyrus from the Tebtunis library. Credits: University of Copenhagen
How It Works? Circular Dichroism
A lot of modern research involves exploring the tiniest things in tremendous detail. Scientists can spend months and even years focused on a single protein.
Proteins are the molecular engines of our cells and much like mending a car the first step with developing therapeutic drugs is to understand how protein works. A hundred thousand times smaller than the cross section of a human hair, extremely small proteins are shaped like long necklaces with many beads. Shaped differently, these beads are called amino acids. Joined together they make thousands of protein structures that define their properties, function and activity.
Biochemistry and adaptive colouration of an exceptionally preserved juvenile fossil sea turtle
Johan Lindgren – together with colleagues abroad as well as at his own department and at the infrared microspectroscopy beamline D7 at the old MAX IV Laboratory in Lund – studied the biomolecular inventory of the fossil turtle. The researchers identified residues of several different molecules, including beta-keratin, eumelanin, haemoglobin, and tropomyosin. Eumelanin is a pigment that provides dark skin colour also in humans. Researchers at Lund University in Sweden have discovered well-preserved pigments and other biomolecules in a 54 million-year-old baby sea turtle. The molecular analyses show that the turtle’s shell contained pigments to protect it from harmful UV rays of the sun.
Read more on the MAX-IV website
Image: Holotype of Tasbacka danica. (a) Photograph of the fossil. Fo, fontanelle (the light colour is a result of sediment infill); Hyo, hyoplastron; Hyp, hypoplastron; Ne, neural; Nu, nuchal; Pe, peripheral; Py, pygal. Arrowheads indicate neural nodes. (b) Detail of the carapace with the sampled area demarcated by a circle. Co, costal; Hu, humerus; Sc, scapula. (c) Higher magnification image showing marginal scutes (arrowheads), pigmentations on bones (arrows), and a brown-black film covering the fontanelles (stars).
New catalysts for the synthesis of organic compounds
Research proposes new mechanism for Suzuki-type C-C homocoupling reaction catalyzed by palladium nanocubes
The production of chemical compounds from simpler organic molecules is of great importance for various industrial processes. It is based on the bonding between carbons of the precursor organic compounds, aided by catalysts (typically transition metals). These reactions make it possible to obtain natural and synthetic substances for the development of new materials, such as polymers and pharmaceuticals.
In particular, the so-called carbon-carbon (CC) cross-coupling reactions, in which two different precursor molecules are bound to form the final chemical compound, are of such importance that their development granted the 2010 Nobel Prize in chemistry to researchers Richard F. Heck, Ei-ichi Negishi and Akira Suzuki.
Another type of coupling reaction is the C-C homocoupling reaction, in which two similar precursor molecules bond forming a symmetrical final compound. These reactions began to gain prominence due to their similarities to cross-coupling reactions, which allowed the optimization and development of new catalysts for both mechanisms.
>Read more on the Brazilian Synchrotron Light Laboratory website
How mammal ancestors evolved #weekendusers
The key is in the whiskers
Mammal’s ancestors evolved in size and appearance throught millions of years to avoid predators. Researchers from the University of Witswatersrand are on ID19 this weekend to find out whether whiskers played a role in this evolution.
Image: The team in the experimental hutch with one of the samples. Credits: C. Argoud
Magnetic structures take a new turn
The unexpected finding that in an ‘artificial spin ice’ magnetostatic energy can be transformed into directed rotation of magnetization provides fresh insights into such nano-patterned magnetic structures — and might enable novel applications in nanoscale devices.
Magnetism and rotation are intimately related. This connection can lead to surprising and non-intuitive effects, as first demonstrated a century ago, when it was predicted, and observed, that changing the magnetization in a piece of ferromagnetic material (such as iron) rotates it, ever so slightly; conversely, spinning a non-magnetised piece of the same material magnetizes it. These phenomena are known as Einstein—de Haas and Barnett effects, respectively, and are beautiful phenomena described in many physics textbooks. Now, Sebastian Gliga and colleagues in the Laboratory for Multiscale Materials Experiments at PSI, led by of Laura Heyderman, report in Nature Materials [1] the discovery of another sort of rotation in a magnetic structure, one that came as a surprise. They observed that after magnetising their sample, the magnetisation started to consistently rotate in one of two possible directions, without an obvious reason why one way should be preferred over the other.
Maximal Rashba-like spin splitting via kinetic-energy-coupled inversion-symmetry breaking
Research collaboration led by Professor Philip King from University of St. Andrews, and comprising the researchers from Max Planck Institute for Chemical Physics of Solids in Dresden, Institute for Theoretical Physics of the University of Heidelberg and researchers from I05 beamline at Diamond Light Source and APE beamline at Elettra, described a new route to maximise the spin-splitting of surface states.
The electronic properties of surfaces are often different from those of the bulk. In particular, the intrinsically broken symmetries of the surface compared with the bulk of the material allow for appearance of the new electronic surface states. For the systems in which spin-orbit interaction is strong, a non-negligible separation of these states according to their spin takes place. The spin splitting of surface- or interface-localized two-dimensional electron gases is characterized by a locking of the electron spin perpendicular to its momentum.
Read more on the Elettra website.
(a) Bulk and surface Fermi surfaces of PtCoO2 measured by ARPES; (b) Expected spin texture of the surface states; (c) Spin-resolved ARPES measurements of an in-plane spin polarization (〈Sy〉) of the Fermi surface for the cut along kx.