Sentences with phrase «oxidation state»
The phrase "oxidation state" refers to the level of charge or electron distribution of an atom within a compound. It helps determine which atoms are gaining or losing electrons during a chemical reaction. Full definition
He then outlines the various oxidation states of iron — the origin of its wealthy chemistry.
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Simply having different oxidation states is not enough to make an element work for a liquid battery.
They focused on the satellite structures and showed that the energy separation between the satellite and primary peaks was diagnostic of uranium oxidation states over a broad range of compounds with very different compositions.
A first improvement in the junction stability can be obtained with a mild oxidation of the porous silicon surface because of the enhancement of the DHI — surface interaction, and calculations have shown that the higher oxidation states in DHI oligomers create more favorable conditions for the efficient adhesion of eumelanin on silicon surface.
For example, the vinyl groups in haem, among other things, help to stabilise the iron (II) oxidation state by acting as a repository for the iron's electrons.
Through this interdisciplinary effort the team was able to fully characterise the molecules and determine that the ITI operates in these molecules that contain metal ions in only the +4 oxidation state.
«However, the ITI was previously limited only to actinides in their maximum or close or maximum oxidation states.
«One reason this question had been difficult to tackle was the lack of structurally comparable families of molecules from which to conduct comparative studies where lower oxidation states of metal ions could be investigated.»
«This makes the uranyl moiety very important, but also the universal view that the ITI was a niche concept of limited applicability dominated because it was restricted to high oxidation state actinide metals like uranium.
Materials containing atoms that can switch back and forth between multiple oxidation states are technologically important but very rare in nature, says ORNL's Ho Nyung Lee, who led the international research team that published its findings in Nature Materials.
«Typically, most elements have a stable oxidation state, and they want to stay there,» Lee said.
«To be 100 percent sure, we did large computational simulations and compared them to the experimental data and determined that they were, indeed, seeing berkelium in an unusual oxidation state.»
The researchers used a vanadium - based compound because vanadium is a transition metal with various oxidation states, which can be exploited to reach higher capacities.
Often oxidation states are hard to tell apart, but in this case nature was kind: V (+2) is purple, V (+3) green, V (+4) blue, and V (+5) yellow.
Iron is not only fascinating chemically, having six more oxidation states than silver, but it has a rich biological chemistry too, forming the core of the oxygen - carrying proteins in blood — myoglobin and haemoglobin — and playing centre field in many enzymatic systems.
Researchers found that the volatility and oxidation state of isoprene SOA are sensitive to, and exhibit a nonlinear dependence on, NOx levels.
When two electrolytes, each containing ions with different oxidation states, are allowed to exchange charges, the result is an electric current.
In other homogeneous (or heterogeneous) catalyst systems in which the metal is likely to be in a relatively high oxidation state, such as molybdenum (VI) or tungsten (VI), metal - carbon multiple bonds may play an important role.
Although each has a radically different chemical structure, they all increased the oxidation state of human cells.
Neutrons probed two mechanisms proposed to explain what happens when hydrogen gas flows over a cerium oxide (CeO2) catalyst that has been heated in an experimental chamber to different temperatures to change its oxidation state.
Meanwhile, Franklin Tao, Luan Nguyen and Xiaoyan Zhang of the University of Kansas used ambient pressure X-ray photoelectron spectroscopy to characterize the oxidation state of cerium oxide, which was critical to deriving the mechanism.
Using a diesel oxidation catalytic converter (DOC), in which afterburning of hydrocarbons and carbon monoxide takes place, the scientists of Karlsruhe Institute of Technology (KIT) and their partners found that the particle size and oxidation state of the platinum component during operation can be modified specifically.
The pattern of absorption of the beam by the material gave the researchers information about the oxidation state of iron in the nanoparticles in the X-ray beam.
By rotating the material in space, they could create a three - dimensional tomographic reconstruction of the oxidation states of each nanoparticle.
When the iron was in an oxidation state that predominated on early Earth, iron (II), nothing happened.
Two methods may be applied: (i) X-ray absorption spectroscopy (XAS) allows the determination of oxidation state and coordination number, i.e. the number of nearest neighbors of an atom; (ii) X-ray emission spectroscopy (XES) which can be used to distinguish between different molecules adsorbed on the catalytic converter.
Redox reactions include all chemical processes in which atoms have their oxidation number (oxidation state) changed.
Vanadium has four oxidation states, known as V (+2), V (+3), V (+4), and V (+5); in each state the element carries a different amount of electric charge.
These charged atoms or molecules are known as ions, and the amount of charge on an ion is known as its oxidation state.
The electrical conductivity of these polymers depends on their oxidation state — that is, the number of positive or negative charges in their polymer chains.
The team realised that the symmetry of the complexes and oxidation state of the uranium ions rendered them ideal systems from which to develop quantitative models.
Complex oxides can exhibit many interesting physical properties including magnetism, ferroelectricity, and superconductivity, and all these properties vary sensitively with the oxidation state of the material.
Photosytem II utilizes a water - splitting manganese - calcium enzyme that when energized by sunlight catalyzes a four photon - step cycle of oxidation states (S0 - to - S3).
At the core of photosystem II is a manganese - calcium (Mn4Ca) metalloenzyme complex that when energized by solar photons catalyzes a four photon - step cycle of oxidation states (S0 - to - S3) that ultimately yields molecular oxygen.
Instead, the oxidation state of certain elements like manganese or iron may have been more important for life, if it ever existed on Mars,» study coauthor Roger Wiens said.
The article «Pinpointing Intermediates,» identifies the key geometries and oxidation states in catalysts for NOx cleanup, and shows the connection to enzyme catalysis.
In nickel - rich areas, the trapped electrons change the oxidation state of nearby manganese ions, from Mn +4 to Mn +3, producing shallow electron states that alter the stability of the material's lattice.
In this approach all of the functional groups, oxidation states, and stereochemical elements required to get a diverse array of products are preinstalled into building blocks.
This led to the development of a methodical process for taking XPS data and determining the oxidation state of uranium.
The data they provide can be used in other studies examining the oxidation state of uranium and other metal compounds.
Whether the radionuclide travels to nearby water sources depends on its oxidation state, the number of electrons around the atom.
Ilton and Bagus» method accurately pinpoints uranium's oxidation state.
«XPS Determination of Uranium Oxidation States.»
The calibrations reveal an atmosphere with an oxidation state closer to present - day conditions.
The findings, in a paper titled «The oxidation state of Hadean magmas and implications for early Earth's atmosphere,» have implications for our understanding of how and when life began on this planet and could begin elsewhere in the universe.
Cerium is an important oxidation gauge because it can be found in two oxidation states, with one more oxidized than the other.
«By determining the oxidation state of the magmas that created zircon, we could then determine the types of gases that would eventually make their way into the atmosphere,» said Trail.