A new material has been made to behave in two distinct ways, helping to break down a significant barrier for understanding the mechanisms of high temperature superconductivity. Known high temperature superconductors fall into two different classes — layered cuprates and iron arsenides. The undoped, parent compounds of the cuprates are insulating, while the parent compounds of iron arsenide superconductors are metallic.
You are here
Pectins have a previously unsuspected role in holding plant cells together, according to recent research. Cell walls are made up of three major classes of polysaccharides: cellulose, hemicellulose and pectins. The molecular interactions of these polysaccharides walls were studied for the first time within intact plant cells using multidimensional solid state NMR, a technique related to magnetic resonance imaging (MRI).
The genetic modification of the plant cellulose structure has been demonstrated for the first time.This could be transformative for a bio-based economy. Cellulose is difficult to break down to form the sugars needed to produce biofuels.
Scientists have designed a device to achieve the seeming-impossibility of confining light to a space with dimensions smaller than its wavelength. The deceptively simple device is a pipe with a tiny bore, and walls made of so-called transformation optical materials. To understand how these materials work, consider first what happens when light hits water. Light changes directions, because of the difference in the refractive index of water versus air; it hits the water at one angle and travels through it at a different angle.
Scientists have advanced methods to make maps of the locations of molecules within plant materials. Resolution of 10 to 50 microns, less than a quarter the size of a human hair, is routinely possible.
Designing the building blocks of artificially engineered materials, known as metamaterials, just got easier. Metamaterials are built from small engineered structures that, in some ways, mimic the role of atoms, and can manipulate light in ways not seen in nature. The conducting materials used to make them are central to their efficiency. Energy is lost by conversion of light to heat in the metallic components and the support materials. Gold and silver are known to be relatively good building block materials and now we have a way to predict which other materials could work even better.
Researchers can now analyze how reactions proceed inside porous nanoparticles where the molecules are in such narrow channels that they cannot pass each other. Catalysis within these confined conditions is significantly impacted by restricted transport. Typical pore diameters are in the range of 2 - 10 nm, and with catalyst molecules attached inside them, the pore diameter can be reduced below 2 nm.
Researchers have overcome a fundamental obstacle to realizing the full potential of quantum computing.They developed a method to protect quantum information while simultaneously performing calculations. When a quantum bit (qubit) interacts with the environment its quantum information is quickly destroyed. Until now, methods to decouple individual qubits from the environment isolated the qubits from each other so they could not exchange information. The scientists devised a scheme that seamlessly integrates decoupling from the environment into the quantum computation process.
Researchers have shown that it may be possible to make lasers using single-layer sheets of carbon atoms — the novel material known as graphene. Lasers are made from materials that can absorb ordinary light and then emit photons that have matching waves to provide high intensity.To generate laser power, a material must first undergo a population inversion where an excess of electrons is excited.
Advanced techniques have revealed what happens to the magnetism in an iron-arsenide superconductor when some of the iron atoms are replaced by iridium.Substituting some iron atoms by transition metals (TM) such as cobalt, nickel, platinum and iridium suppresses the magnetic order of the non-superconducting parent phases of the iron pnictides, which promotes superconductivity. The way this happens remains one of the most intriguing puzzles in the field.