Sentences with phrase «hydrogen bond forms»

Not exact matches

Hydrogen atoms contained in water readily bond with the heavy isotope to form hydrochloric acid gas, which then leaks into space — leaving more of the lighter isotope behind.

«Previous research used reversible hydrogen bonds to connect polymers to form a rubber but reversible bonds are intrinsically weaker than covalent bonds,» said Li - Heng Cai, a postdoctoral fellow at SEAS and corresponding author of the paper.

About four billion years ago, the strength of those hydrogen - carbon bonds allowed increasingly complex molecules — amino acids, DNA, and proteins — to form from the primordial soup, making life possible.

These groups readily form hydrogen bonds that helped the fibers make tight contacts with one another, further strengthening the material.

Water molecules are linked together by hydrogen bonds that break and form several thousands of billions of times per second.

«That's what his advance is pointing towards,» he says, «finding an alternative catalyst that will allow us to do oxygen evolution (breaking the bonds of water or H2O and forming oxygen) in concert with hydrogen» on a grand scale.

In recent years researchers have achieved better performance with compounds such as lithium borohydride, in which the metal atoms form weaker, ionic bonds with groups containing several hydrogen atoms.

Water molecules in the solid state, such as in ice and snow, form weak bonds (called hydrogen bonds) to one another.

Individually they are weak, together they form the cement that holds together a whole new family of designer materials sings the praises of hydrogen bonds

Atoms of most elements, such as hydrogen, oxygen and carbon, form tight chemical bonds by sharing electrons with their neighbours in order to give each atom a stable configuration of electrons.

Of the two types of atom, oxygen has more pull on the electrons that they share to form the bonds between them, so the oxygen becomes slightly negatively charged and the hydrogens slightly positive.

The researchers discovered that these catalysts — copper in the form of a white salt and the ligand as an oil — can oxidize C - H bonds in a very efficient way in combination with hydrogen peroxide, a reduced form of oxygen that nature uses.

The amalgamation of these techniques provided a fully characterized structure, one in which the dissolved carbon dioxide acts as a hydrophobe, having formed only very weak hydrogen bonds to the surrounding water molecules.

Scientists from Tomsk Polytechnic University together with their colleagues from USA and Japan have proposed a novel way to address the most important and fundamental challenge of organic chemistry, i.e. breaking a bond between carbon and hydrogen atoms to form new organic substances.

In order to obtain new compounds, it is necessary to break the bond of carbon and hydrogen to form carbon - carbon bond,» explains the researcher.

When the water is drained away Berglund found that the fibres join together into networks held by hydrogen bonds, forming flat sheets of «nanopaper».

When ethanol dissolves in water, the ethanol molecules remain intact but form new hydrogen bonds with the water.

Intramolecular insertion of metal nitrenes into carbon - hydrogen bonds to form γ - lactam rings has traditionally been hindered by competing isocyanate formation.

The amino acid proline is special among the natural amino acids because it can not form hydrogen bonds to other structural parts of the peptide when integrated in a peptide.

The structures and properties of these T - shaped intermediates are broadly similar to hydrogen - bonded complexes such as that formed between ethene and hydrogen chloride.

First, they occurred quickly and the resulting nucleotides spontaneously paired with each other in water, forming hydrogen bonds like the Watson - Crick base pairs that create the «ladder - rung» pattern inside RNA and DNA helixes.

«Most self - healing polymers form hydrogen bonds or metal - ligand coordination, but these aren't suitable for ionic conductors,» Wang says.

Again, the first one stripped off hydrogens from adjacent carbon atoms in both the long polyethylene chains and short alkanes to form double bonds; the second split the molecules and randomly stitched split molecules back together.

Both materials were then sprayed with hydrogen gas in which the bonds were broken to form single hydrogen atoms.

«The Ru catalyst precisely distinguishes butadiene and substituted acetylene molecules and new carbon - carbon bonds are formed among a butadiene with two acetylenes just by migration of the terminal hydrogen atoms in butadiene.

Water, for example, with one oxygen and two hydrogen atoms, can form two hydrogen bonds per molecule.

Aspirin, for example, contains just 21 atoms (nine carbons, eight hydrogens and four oxygens) bonded together to form a particular shape.

«Melanie Sanford's insightful studies on the details as well as applications in the field of carbon - hydrogen bond activation have led to new methods to efficiently modify existing pharmaceuticals to arrive at new and better forms in a more efficient and rapid way than was previously possible.

After careful analysis, the research team determined that an ammonia molecule forms a nearly linear hydrogen bond with another ammonia molecule and that additional hydrogen bonds with another ammonia molecules do not perturb this pattern.

Why it matters: Hydrogen bonds and the networks they form play an important role in understanding and controlling processes from refining crude oil to metabolizing proteins.

High concentrations result in acid forming hydrogen bonds and more structure, reducing dissociation

They also found that each water molecule formed four hydrogen bonds — three with other molecules in the same layer, and one with water in the other layer.

Wiedner and Bullock focused on a cobalt catalyst and how it forms bonds with hydrogen atoms and shuffles electrons.

The hydrogen bonds with carbon to form methane.

They form transient bonds with the carbon in CO2, making it more willing to bond with hydrogen ions, eventually resulting in the production of methanol.

The polymer and the agent form hydrogen bonds, weak electrostatic connections between polymer's hydrogen and an agent's oxygen atom.

To solve the mystery, Wiedner and Bullock used newer techniques to show how the actors form bonds, trade electrons, and free hydrogen.

This figure also shows that all of the compounds identified possible form hydrogen bonds between the Glu66 residue and the carboxamide group.

An unsaturated fatty acid is missing hydrogens, and as a result the carbons bond to each other twice, forming what is called a double bond.

In nature, the polyunsaturated fatty acids are usually found in the cis form, which means that both hydrogen atoms at the double bond are on the same side.

Monounsaturated: Monounsaturated fatty acids have one double bond in the form of two carbon atoms double - bonded to each other and, therefore, lack two hydrogen atoms.

For instance, Schoenmann explains, microscopic particulates in the air will form hydrogen bonds with a painting's surface so that «no amount of water or scrubbing will be able to remove that dirt.

Meanwhile, Christner says, unraveling the chemistry of ice - binding proteins (which tend to form a hydrogen bond with water molecules) could have important biotech applications.

And so it goes, the bigger the hydrogen bonded water cluster, the easier it is to form a bigger cluster.

But when their temperature is lowered and they form a water molecule, the symmetry of the individual atoms is broken as they form a molecule with 105 degrees between the hydrogen - oxygen bonds.

The structure of the «nanoglue» and the clay nanosheets allowed the layers to form cooperative hydrogen bonds, which gives rise to what Kotov called «the Velcro effect.»

The polymer can readily form hydrogen bonds with water.