Sentences with phrase «platinum atoms»

Each platinum cluster typically contains 30 platinum atoms; within the whole nanoparticle there are approximately 1,680 titanium atoms and 180 platinum atoms.

The number of four - bonded atoms stayed constant, suggesting that platinum atoms anchor at sites with come - hither, five - bonded aluminum atoms, so - called penta sites.

For example, the analysis revealed chemical order and disorder in interlocking grains, in which the iron and platinum atoms are arranged in different patterns.

«This understanding we've gained suggests some additional tricks one could play to get better dispersion of the platinum atoms,» said Peden.

More penta sites meant more platinum atoms bound to the support.

Having found anchor points, the team zoomed in with the JEOL 2200FS aberration - corrected microscope, which could discern individual platinum atoms, at HTML.

Identification of the precise 3 - D coordinates of iron, shown in red, and platinum atoms in an iron - platinum nanoparticle..

When the researchers looked under the microscope at catalyst material formed with alpha - aluminum oxide, platinum atoms formed balls that tottered around on the surface instead of tidy rafts.

The platinum atoms gather and form nanoparticles, and the carbon atoms naturally form a matrix around them,» said Maja Dukic, the article's lead author.

The team identified and located more than 6,500 iron and 16,600 platinum atoms and showed how the atoms are arranged in nine grains, each of which contains different ratios of iron and platinum atoms.

«A decisive factor for understanding the life - cycle of the catalysts was the observation that nickel and platinum atoms prefer not to be evenly distributed at the surface of the nano - octahedra,» explains Dr. Marc Heggen from ER - C and the Peter Grünberg Institute at Forschungszentrum Jülich.

Red spheres represent platinum atoms and green spheres represent nickel atoms.

«We found that even at temperatures as low as minus 300 degrees F these platinum atoms were capable of splitting hydrogen molecules into atoms, indicating that the platinum atoms would be very good at activating hydrogen for a chemical reaction,» Sykes said.

The Tufts chemists used a specialized low temperature scanning tunneling microscope to visualize the single platinum atoms and their interaction with hydrogen.

The Tufts researchers discovered that dispersing individual, isolated platinum atoms in much less costly copper surfaces can create a highly effective and cost - efficient catalyst for the selective hydrogenation of 1,3 butadiene, a chemical produced by steam cracking of naphtha or by catalytic cracking of gas oil.

Calculations by Mavrikakis» group show that platinum atoms have a tendency to burrow into the palladium during the deposition.

To create the nano cages, researchers start with a nanoscale cube or octahedron of less expensive palladium, then deposit a few layers of platinum atoms on top of it.

Reactants can flow into the hollow structure through holes in the faces, interacting with more platinum atoms in the chemical reaction than would be the case on a flat sheet of platinum or traditional, nonhollowed nanoparticles.

«Because of this new structure they're taking on, they're naturally shortening the distances between platinum atoms, which makes the platinum more active for the oxygen reduction reaction,» says Luke Roling, a graduate student in Mavrikakis» lab.

The work builds on research, published in Science last year, in which the Wang and Datye groups found a novel way to trap and stabilize individual platinum atoms on the surface of cerium oxide, a commonly used component in emissions control catalysts.

Because of its expense and scarcity, industries are continually looking to use less of it and to develop catalysts that more efficiently use individual platinum atoms in their reactions.

The bonding of the platinum to surface oxygens creates isolated platinum atoms that are thermally stable, and active for treatment of automotive exhaust pollutants.

They revealed that platinum atoms formed multiple layers which piled up as high as 6 nm, the highest among metal superconductor.

The tiny nanoparticles used for catalysis often consist of only a few platinum atoms.

Bliem did not only conduct the experiments, he also performed complex theoretical calculations to explain the peculiar behaviour of the platinum atoms on a quantum mechanical level.

It sounds a bit like an unhappy love story: «Two platinum atoms would actually like to be together, but the magnetite surface keeps them apart,» says Roland Bliem (TU Wien).

The two platinum atoms must once again find separate places on the magnetite surface.

Carbon monoxide plays a dual role in this process: It allows single platinum atoms to move and form pairs, and then it holds these pairs together for a long time.

Only by increasing the temperature can the pair - bonds between platinum atoms can be broken.

The remarkable behaviour of platinum atoms on magnetite surfaces could lead to better catalysts.

When one mobilized platinum atom finds another, they can form a bond — as long as both of them are being lifted up by carbon monoxide, diminishing the influence of the magnetite below.

The lifting process frees the atom from the tight grip of the magnetite, and together, the molecule and the platinum atom can start moving around randomly across the magnetite surface.

The drug is formed from groups of molecules attached to a platinum atom, creating a compound that reacts with DNA in cancer cells.

The single platinum atom holds the carbon monoxide in place while the copper oxide supplies the oxygen to convert it into carbon dioxide.

Not exact matches

One, recently developed by a Hewlett - Packard team, is a «crossbar latch» circuit made of platinum and titanium wires that are only a few dozen atoms in diameter.

Scanning tunneling microscopy, which produces images of individual atoms on a surface, was used to view the behavior of the platinum nanoparticles on the graphene.

Iron atoms travel to the surface from within the material, and right next to the platinum nanoparticle, an additional iron - oxide island is created.

«Ruthenium rules for new fuel cells: Project disperses single atoms on graphene to match platinum standard.»

They also found that lanthanum and arsenic atoms separated platinum layers from each other in a way, they speculate, which weakens the interaction between platinum electrons, allowing them to flow more freely and resulting in the superconducting property.

«Ruthenium is often a highly active catalyst when fixed between arrays of four nitrogen atoms, yet it is one - tenth the cost of traditional platinum,» Tour said.

The so - called single - atom catalyst uses platinum more efficiently while remaining stable at high temperatures.

«It is remarkable that simply combining the ceria with a platinum catalyst was sufficient to allow trapping of the atoms and retaining the performance of the catalyst.

In 1983, for example, the platinum - iridium bar that described the length of the meter yielded to a new benchmark: A meter is now defined as the distance light travels in a vacuum in 1/299, 792,458 second (a second being the time it takes an atom of cesium - 133 to vacillate 9,192,631,770 times between the two hyperfine levels of its ground state).

They synthesized small quantities of realistic catalysts, such as platinum - copper single atom alloy nanoparticles supported on an alumina substrate, and then tested them under industrial pressure and temperatures.

«We were excited to find that the platinum metal dissolved in copper, just like sugar in hot coffee, all the way down to single atoms.

«Single atom alloy platinum - copper catalysts cut costs, boost green technology: New generation of catalysts demonstrated for selective hydrogenation of butadiene.»

A new generation of platinum - copper catalysts that require very low concentrations of platinum in the form of individual atoms to cleanly and cheaply perform important chemical reactions is reported today by Tufts University researchers in the journal Nature Communications.

A group of SISSA / CNR IOM scientists (with the collaboration of the Univerzita Karlova in Prague) has studied a way to produce tiny platinum grains consisting of one atom only and to keep them dispersed in a stable manner, by exploiting the properties of the substrate on which they rest.

The researchers discovered that the unique manner in which the platinum and nickel atoms arrange themselves on the surfaces of these particles serves to optimally accelerate the chemical reaction between hydrogen and oxygen to form water.

«The UCLA group has developed a new experimental technique where they can tell where the atoms are — the coordinates — and the chemical resolution, or what they are — iron or platinum.»